{"question": "A 23-year-old pregnant woman at 22 weeks gestation presents with burning upon urination. She states it started 1 day ago and has been worsening despite drinking more water and taking cranberry extract. She otherwise feels well and is followed by a doctor for her pregnancy. Her temperature is 97.7°F (36.5°C), blood pressure is 122/77 mmHg, pulse is 80/min, respirations are 19/min, and oxygen saturation is 98% on room air. Physical exam is notable for an absence of costovertebral angle tenderness and a gravid uterus. Which of the following is the best treatment for this patient?", "answer": "Nitrofurantoin", "options": {"A": "Ampicillin", "B": "Ceftriaxone", "C": "Ciprofloxacin", "D": "Doxycycline", "E": "Nitrofurantoin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-month-old baby died suddenly at night while asleep. His mother noticed that he had died only after she awoke in the morning. No cause of death was determined based on the autopsy. Which of the following precautions could have prevented the death of the baby?", "answer": "Placing the infant in a supine position on a firm mattress while sleeping", "options": {"A": "Placing the infant in a supine position on a firm mattress while sleeping", "B": "Routine postnatal electrocardiogram (ECG)", "C": "Keeping the infant covered and maintaining a high room temperature", "D": "Application of a device to maintain the sleeping position", "E": "Avoiding pacifier use during sleep"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A mother brings her 3-week-old infant to the pediatrician's office because she is concerned about his feeding habits. He was born without complications and has not had any medical problems up until this time. However, for the past 4 days, he has been fussy, is regurgitating all of his feeds, and his vomit is yellow in color. On physical exam, the child's abdomen is minimally distended but no other abnormalities are appreciated. Which of the following embryologic errors could account for this presentation?", "answer": "Abnormal migration of ventral pancreatic bud", "options": {"A": "Abnormal migration of ventral pancreatic bud", "B": "Complete failure of proximal duodenum to recanalize", "C": "Error in neural crest cell migration", "D": "Abnormal hypertrophy of the pylorus", "E": "Failure of lateral body folds to move ventrally and fuse in the midline"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A pulmonary autopsy specimen from a 58-year-old woman who died of acute hypoxic respiratory failure was examined. She had recently undergone surgery for a fractured femur 3 months ago. Initial hospital course was uncomplicated, and she was discharged to a rehab facility in good health. Shortly after discharge home from rehab, she developed sudden shortness of breath and had cardiac arrest. Resuscitation was unsuccessful. On histological examination of lung tissue, fibrous connective tissue around the lumen of the pulmonary artery is observed. Which of the following is the most likely pathogenesis for the present findings?", "answer": "Thromboembolism", "options": {"A": "Thromboembolism", "B": "Pulmonary ischemia", "C": "Pulmonary hypertension", "D": "Pulmonary passive congestion", "E": "Pulmonary hemorrhage"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old woman presents with menorrhagia for the past several years. She says that her menses “have always been heavy”, and she has experienced easy bruising for as long as she can remember. Family history is significant for her mother, who had similar problems with bruising easily. The patient's vital signs include: heart rate 98/min, respiratory rate 14/min, temperature 36.1°C (96.9°F), and blood pressure 110/87 mm Hg. Physical examination is unremarkable. Laboratory tests show the following: platelet count 200,000/mm3, PT 12 seconds, and PTT 43 seconds. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Von Willebrand disease", "options": {"A": "Factor V Leiden", "B": "Hemophilia A", "C": "Lupus anticoagulant", "D": "Protein C deficiency", "E": "Von Willebrand disease"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old zookeeper presents to the emergency department complaining of severe abdominal pain that radiates to her back, and nausea. The pain started 2 days ago and slowly increased until she could not tolerate it any longer. Past medical history is significant for hypertension and hypothyroidism. Additionally, she reports that she was recently stung by one of the zoo’s smaller scorpions, but did not seek medical treatment. She takes aspirin, levothyroxine, oral contraceptive pills, and a multivitamin daily. Family history is noncontributory. Today, her blood pressure is 108/58 mm Hg, heart rate is 99/min, respiratory rate is 21/min, and temperature is 37.0°C (98.6°F). On physical exam, she is a well-developed, obese female that looks unwell. Her heart has a regular rate and rhythm. Radial pulses are weak but symmetric. Her lungs are clear to auscultation bilaterally. Her lateral left ankle is swollen, erythematous, and painful to palpate. An abdominal CT is consistent with acute pancreatitis. Which of the following is the most likely etiology for this patient’s disease?", "answer": "Scorpion sting", "options": {"A": "Aspirin", "B": "Oral contraceptive pills", "C": "Scorpion sting", "D": "Hypothyroidism", "E": "Obesity"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old primigravida presents to her physician for a routine prenatal visit. She is at 34 weeks gestation, as confirmed by an ultrasound examination. She has no complaints, but notes that the new shoes she bought 2 weeks ago do not fit anymore. The course of her pregnancy has been uneventful and she has been compliant with the recommended prenatal care. Her medical history is unremarkable. She has a 15-pound weight gain since the last visit 3 weeks ago. Her vital signs are as follows: blood pressure, 148/90 mm Hg; heart rate, 88/min; respiratory rate, 16/min; and temperature, 36.6℃ (97.9℉). The blood pressure on repeat assessment 4 hours later is 151/90 mm Hg. The fetal heart rate is 151/min. The physical examination is significant for 2+ pitting edema of the lower extremity. Which of the following tests o should confirm the probable condition of this patient?", "answer": "24-hour urine protein", "options": {"A": "Bilirubin assessment", "B": "Coagulation studies", "C": "Hematocrit assessment", "D": "Leukocyte count with differential", "E": "24-hour urine protein"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3900-g (8.6-lb) male infant is delivered at 39 weeks' gestation via spontaneous vaginal delivery. Pregnancy and delivery were uncomplicated but a prenatal ultrasound at 20 weeks showed a defect in the pleuroperitoneal membrane. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Gastric fundus in the thorax", "options": {"A": "Gastric fundus in the thorax", "B": "Pancreatic ring around the duodenum", "C": "Small and cystic kidneys", "D": "Hypertrophy of the gastric pylorus", "E": "Large bowel in the inguinal canal"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old woman presents for a regular check-up. She complains of lightheadedness and palpitations which occur episodically. Past medical history is significant for a myocardial infarction 6 months ago and NYHA class II chronic heart failure. She also was diagnosed with grade I arterial hypertension 4 years ago. Current medications are aspirin 81 mg, atorvastatin 10 mg, enalapril 10 mg, and metoprolol 200 mg daily. Her vital signs are a blood pressure of 135/90 mm Hg, a heart rate of 125/min, a respiratory rate of 14/min, and a temperature of 36.5°C (97.7°F). Cardiopulmonary examination is significant for irregular heart rhythm and decreased S1 intensity. ECG is obtained and is shown in the picture (see image). Echocardiography shows a left ventricular ejection fraction of 39%. Which of the following drugs is the best choice for rate control in this patient?", "answer": "Digoxin", "options": {"A": "Atenolol", "B": "Verapamil", "C": "Diltiazem", "D": "Propafenone", "E": "Digoxin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old male presents to his primary care physician with complaints of seasonal allergies. He has been using intranasal vasoconstrictors several times per day for several weeks. What is a likely sequela of the chronic use of topical nasal decongestants?", "answer": "Persistent congestion", "options": {"A": "Epistaxis", "B": "Hypertension", "C": "Permanent loss of smell", "D": "Persistent nasal crusting", "E": "Persistent congestion"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 46-year-old woman comes to the physician because of a 2-week history of diplopia and ocular pain when reading the newspaper. She also has a 3-month history of amenorrhea, hot flashes, and increased sweating. She reports that she has been overweight all her adult life and is happy to have lost 6.8-kg (15-lb) of weight in the past 2 months. Her pulse is 110/min, and blood pressure is 148/98 mm Hg. Physical examination shows moist palms and a nontender thyroid gland that is enlarged to two times its normal size. Ophthalmologic examination shows prominence of the globes of the eyes, bilateral lid retraction, conjunctival injection, and an inability to converge the eyes. There is no pain on movement of the extraocular muscles. Visual acuity is 20/20 bilaterally. Neurologic examination shows a fine resting tremor of the hands. Deep tendon reflexes are 3+ with a shortened relaxation phase. Which of the following is the most likely cause of this patient's ocular complaints?", "answer": "Glycosaminoglycan accumulation in the orbit", "options": {"A": "Granulomatous inflammation of the cavernous sinus", "B": "Abnormal communication between the cavernous sinus and the internal carotid artery", "C": "Glycosaminoglycan accumulation in the orbit", "D": "Bacterial infection of the orbital contents", "E": "Sympathetic hyperactivity of levator palpebrae superioris\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 1-year-old boy presents to the emergency department with weakness and a change in his behavior. His parents state that they first noticed the change in his behavior this morning and it has been getting worse. They noticed the patient was initially weak in his upper body and arms, but now he won’t move his legs with as much strength or vigor as he used to. Physical exam is notable for bilateral ptosis with a sluggish pupillary response, a very weak sucking and gag reflex, and shallow respirations. The patient is currently drooling and his diaper is dry. The parents state he has not had a bowel movement in over 1 day. Which of the following is the pathophysiology of this patient’s condition?", "answer": "Blockade of presynaptic acetylcholine release at the neuromuscular junction", "options": {"A": "Antibodies against postsynaptic nicotinic cholinergic ion channels", "B": "Autoantibodies against the presynaptic voltage-gated calcium channels", "C": "Autoimmune demyelination of peripheral nerves", "D": "Blockade of presynaptic acetylcholine release at the neuromuscular junction", "E": "Lower motor neuron destruction in the anterior horn"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 9-month-old female is brought to the emergency department after experiencing a seizure. She was born at home and was normal at birth according to her parents. Since then, they have noticed that she does not appear to be achieving developmental milestones as quickly as her siblings, and often appears lethargic. Physical exam reveals microcephaly, very light pigmentation (as compared to her family), and a \"musty\" body odor. The varied manifestations of this disease can most likely be attributed to which of the following genetic principles?", "answer": "Pleiotropy", "options": {"A": "Anticipation", "B": "Incomplete penetrance", "C": "Multiple gene mutations", "D": "Pleiotropy", "E": "Variable expressivity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old man comes to the physician for evaluation of decreased hearing, dizziness, and ringing in his right ear for the past 6 months. Physical examination shows multiple soft, yellow plaques and papules on his arms, chest, and back. There is sensorineural hearing loss and weakness of facial muscles bilaterally. His gait is unsteady. An MRI of the brain shows a 3-cm mass near the right internal auditory meatus and a 2-cm mass at the left cerebellopontine angle. The abnormal cells in these masses are most likely derived from which of the following embryological structures?", "answer": "Neural crest", "options": {"A": "Neural tube", "B": "Surface ectoderm", "C": "Neural crest", "D": "Notochord", "E": "Mesoderm"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old woman comes to the physician because of coughing and fatigue during the past 2 years. In the morning, the cough is productive of white phlegm. She becomes short of breath walking up a flight of stairs. She has hypertension and hyperlipidemia. She has recently retired from working as a nurse at a homeless shelter. She has smoked 1 pack of cigarettes daily for 40 years. Current medications include ramipril and fenofibrate. Her temperature is 36.5°C (97.7°F), respirations are 24/min, pulse is 85/min, and blood pressure is 140/90 mm Hg. Scattered wheezing and rhonchi are heard throughout both lung fields. There are no murmurs, rubs, or gallops but heart sounds are distant. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Progressive obstruction of expiratory airflow", "options": {"A": "Chronic decrease in pulmonary compliance", "B": "Local accumulation of kinins", "C": "Mycobacterial invasion of pulmonary parenchyma", "D": "Progressive obstruction of expiratory airflow", "E": "Incremental loss of functional residual capacity\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 68-year-old man presents to the emergency department with leg pain. He states that the pain started suddenly while he was walking outside. The patient has a past medical history of diabetes, hypertension, obesity, and atrial fibrillation. His temperature is 99.3°F (37.4°C), blood pressure is 152/98 mmHg, pulse is 97/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam is notable for a cold and pale left leg. The patient’s sensation is markedly diminished in the left leg when compared to the right, and his muscle strength is 1/5 in his left leg. Which of the following is the best next step in management?", "answer": "Heparin drip", "options": {"A": "CT angiogram", "B": "Graded exercise and aspirin", "C": "Heparin drip", "D": "Surgical thrombectomy", "E": "Tissue plasminogen activator"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 76-year-old African American man presents to his primary care provider complaining of urinary frequency. He wakes up 3-4 times per night to urinate while he previously only had to wake up once per night. He also complains of post-void dribbling and difficulty initiating a stream of urine. He denies any difficulty maintaining an erection. His past medical history is notable for non-alcoholic fatty liver disease, hypertension, hyperlipidemia, and gout. He takes aspirin, atorvastatin, enalapril, and allopurinol. His family history is notable for prostate cancer in his father and lung cancer in his mother. He has a 15-pack-year smoking history and drinks alcohol socially. On digital rectal exam, his prostate is enlarged, smooth, and non-tender. Which of the following medications is indicated in this patient?", "answer": "Tamsulosin", "options": {"A": "Clonidine", "B": "Hydrochlorothiazide", "C": "Midodrine", "D": "Oxybutynin", "E": "Tamsulosin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old man comes to the physician because of recurrent episodes of nausea and abdominal discomfort for the past 4 months. The discomfort is located in the upper abdomen and sometimes occurs after eating, especially after a big meal. He has tried to go for a walk after dinner to help with digestion, but his complaints have only increased. For the past 3 weeks he has also had symptoms while climbing the stairs to his apartment. He has type 2 diabetes mellitus, hypertension, and stage 2 peripheral arterial disease. He has smoked one pack of cigarettes daily for the past 45 years. He drinks one to two beers daily and occasionally more on weekends. His current medications include metformin, enalapril, and aspirin. He is 168 cm (5 ft 6 in) tall and weighs 126 kg (278 lb); BMI is 45 kg/m2. His temperature is 36.4°C (97.5°F), pulse is 78/min, and blood pressure is 148/86 mm Hg. On physical examination, the abdomen is soft and nontender with no organomegaly. Foot pulses are absent bilaterally. An ECG shows no abnormalities. Which of the following is the most appropriate next step in diagnosis?", "answer": "Cardiac stress test", "options": {"A": "Esophagogastroduodenoscopy", "B": "CT scan of the abdomen", "C": "Hydrogen breath test", "D": "Cardiac stress test", "E": "Abdominal ultrasonography of the right upper quadrant"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old female presents to general medical clinic for a routine checkup. She has a genetic disease marked by a mutation in a chloride transporter. She has a history of chronic bronchitis. She has a brother with a similar history of infections as well as infertility. Which of the following is most likely true regarding a potential vitamin deficiency complication secondary to this patient's chronic illness?", "answer": "It may manifest itself as a prolonged PT", "options": {"A": "It may result in connective tissue defects", "B": "It may result in corneal vascularization", "C": "It may result in the triad of confusion, ophthalmoplegia, and ataxia", "D": "It may be exacerbated by excessive ingestion of raw eggs", "E": "It may manifest itself as a prolonged PT"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 36-year-old man comes to the physician for a yellow discoloration of his skin and dark-colored urine for 2 weeks. He does not drink any alcohol. Physical examination shows jaundice. Abdominal and neurologic examinations show no abnormalities. Serum studies show increased levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). A liver biopsy is performed and a photomicrograph after periodic acid-Schiff-staining is shown. Which of the following is the most likely additional finding in this patient?", "answer": "Bullous changes of the lung bases on chest CT", "options": {"A": "Tropheryma whipplei-specific RNA on PCR", "B": "Bullous changes of the lung bases on chest CT", "C": "Beading of intra- and extrahepatic bile ducts on ERCP", "D": "Myocardial iron deposition on cardiovascular MRI", "E": "Dark corneal ring on slit-lamp examination"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 69-year-old male presents to the emergency room with back pain. He has a history of personality disorder and metastatic prostate cancer and was not a candidate for surgical resection. He began chemotherapy but discontinued due to unremitting nausea. He denies any bowel or bladder incontinence. He has never had pain like this before and is demanding morphine. The nurse administers IV morphine and he feels more comfortable. Vital signs are stable. On physical examination you note tenderness to palpation along the lower spine, weakness in the bilateral lower extremities, left greater than right. Neurological examination is also notable for hyporeflexia in the knee and ankle jerks bilaterally. You conduct a rectal examination, which reveals saddle anesthesia. Regarding this patient, what is the most likely diagnosis and the appropriate next step in management?", "answer": "The most likely diagnosis is cauda equina syndrome and steroids should be started prior to MRI", "options": {"A": "The most likely diagnosis is cauda equina syndrome and steroids should be started prior to MRI", "B": "The most likely diagnosis is cauda equina syndrome and steroids should be started after to MRI", "C": "The most likely diagnosis is cauda equina syndrome and the patient should be rushed to radiation", "D": "The most likely diagnosis is conus medullaris syndrome and steroids should be started prior to MRI", "E": "The most likely diagnosis is conus medullaris syndrome and steroids should be started after to MRI"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator is studying the function of the lateral nucleus of the hypothalamus in an experimental animal. Using a viral vector, the genes encoding chloride-conducting channelrhodopsins are injected into this nucleus. Photostimulation of the channels causes complete inhibition of action potential generation. Persistent photostimulation is most likely to result in which of the following abnormalities in these animals?", "answer": "Anorexia", "options": {"A": "Hypothermia", "B": "Hyperthermia", "C": "Polydipsia", "D": "Nocturnal hyperactivity", "E": "Anorexia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old woman comes to the physician because of a 6-month history of generalized fatigue, low-grade fever, and a 10-kg (22-lb) weight loss. Physical examination shows generalized pallor and splenomegaly. Her hemoglobin concentration is 7.5 g/dL and leukocyte count is 41,800/mm3. Leukocyte alkaline phosphatase activity is low. Peripheral blood smear shows basophilia with myelocytes and metamyelocytes. Bone marrow biopsy shows cellular hyperplasia with proliferation of immature granulocytic cells. Which of the following mechanisms is most likely responsible for this patient's condition?", "answer": "Unregulated expression of the ABL1 gene", "options": {"A": "Overexpression of the c-KIT gene", "B": "Cytokine-independent activation of the JAK-STAT pathway", "C": "Loss of function of the APC gene", "D": "Altered expression of the retinoic acid receptor gene", "E": "Unregulated expression of the ABL1 gene"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old woman is in the hospital recovering from a cholecystectomy performed 3 days ago that was complicated by cholangitis. She is being treated with IV piperacillin-tazobactam. She calls the nurse to her room because she says that her heart is racing. She also demands that someone come in to clean the pile of garbage off of the floor because it is attracting flies. Her pulse is 112/min, respiratory rate is 20/min, temperature is 38.0°C (100.4°F), and blood pressure is 150/90 mm Hg. On physical examination, the patient appears sweaty, distressed, and unable to remain still. She is oriented to person, but not place or time. Palpation of the abdomen shows no tenderness, rebound, or guarding. Which of the following is the most likely diagnosis in this patient?", "answer": "Delirium tremens", "options": {"A": "Acute cholangitis", "B": "Alcoholic hallucinosis", "C": "Delirium tremens", "D": "Hepatic encephalopathy", "E": "Thyroid storm"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old woman comes to the emergency department because of a photosensitive blistering rash on her hands, forearms, and face for 3 weeks. The lesions are not itchy. She has also noticed that her urine has been dark brown in color recently. Twenty years ago, she was successfully treated for Coats disease of the retina via retinal sclerotherapy. She is currently on hormonal replacement therapy for perimenopausal symptoms. Her aunt and sister have a history of a similar skin lesions. Examination shows multiple fluid-filled blisters and oozing erosions on the forearms, dorsal side of both hands, and forehead. There is hyperpigmented scarring and patches of bald skin along the sides of the blisters. Laboratory studies show a normal serum ferritin concentration. Which of the following is the most appropriate next step in management to induce remission in this patient?", "answer": "Begin phlebotomy therapy", "options": {"A": "Pursue liver transplantation", "B": "Begin oral thalidomide therapy", "C": "Begin phlebotomy therapy", "D": "Begin oral hydroxychloroquine therapy", "E": "Begin subcutaneous deferoxamine therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 53-year-old man comes to the emergency department because of severe right-sided flank pain for 3 hours. The pain is colicky, radiates towards his right groin, and he describes it as 8/10 in intensity. He has vomited once. He has no history of similar episodes in the past. Last year, he was treated with naproxen for swelling and pain of his right toe. He has a history of hypertension. He drinks one to two beers on the weekends. Current medications include amlodipine. He appears uncomfortable. His temperature is 37.1°C (99.3°F), pulse is 101/min, and blood pressure is 130/90 mm Hg. Examination shows a soft, nontender abdomen and right costovertebral angle tenderness. An upright x-ray of the abdomen shows no abnormalities. A CT scan of the abdomen and pelvis shows a 7-mm stone in the proximal ureter and grade I hydronephrosis on the right. Which of the following is most likely to be seen on urinalysis?", "answer": "Urinary pH: 4.7", "options": {"A": "Urinary pH: 7.3", "B": "Urinary pH: 4.7", "C": "Hexagon shaped crystals", "D": "Positive nitrites test", "E": "Largely positive urinary protein"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 5-year-old girl is brought to the clinic by her mother for excessive hair growth. Her mother reports that for the past 2 months she has noticed hair at the axillary and pubic areas. She denies any family history of precocious puberty and reports that her daughter has been relatively healthy with an uncomplicated birth history. She denies any recent illnesses, weight change, fever, vaginal bleeding, pain, or medication use. Physical examination demonstrates Tanner stage 4 development. A pelvic ultrasound shows an ovarian mass. Laboratory studies demonstrates an elevated level of estrogen. What is the most likely diagnosis?", "answer": "Granulosa cell tumor", "options": {"A": "Congenital adrenal hyperplasia", "B": "Granulosa cell tumor", "C": "Idiopathic precocious puberty", "D": "McCune-Albright syndrome", "E": "Sertoli-Leydig tumor"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 16-year-old boy is brought to the physician by his mother because she is worried about his behavior. Yesterday, he was expelled from school for repeatedly skipping classes. Over the past 2 months, he was suspended 3 times for bullying and aggressive behavior towards his peers and teachers. Once, his neighbor found him smoking cigarettes in his backyard. In the past, he consistently maintained an A grade average and had been a regular attendee of youth group events at their local church. The mother first noticed this change in behavior 3 months ago, around the time at which his father moved out after discovering his wife was having an affair. Which of the following defense mechanisms best describes the change in this patient's behavior?", "answer": "Acting out", "options": {"A": "Suppression", "B": "Acting out", "C": "Projection", "D": "Passive aggression", "E": "Regression"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 63-year-old woman presents to her primary-care doctor for a 2-month history of vision changes, specifically citing the gradual onset of double vision. Her double vision is present all the time and does not get better or worse throughout the day. She has also noticed that she has a hard time keeping her right eye open, and her right eyelid looks 'droopy' in the mirror. Physical exam findings during primary gaze are shown in the photo. Her right pupil is 6 mm and poorly reactive to light. The rest of her neurologic exam is unremarkable. Laboratory studies show an Hb A1c of 5.0%. Which of the following is the next best test for this patient?", "answer": "MR angiography of the head", "options": {"A": "CT head (non-contrast)", "B": "Direct fundoscopy", "C": "Intraocular pressures", "D": "MR angiography of the head", "E": "Temporal artery biopsy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying the modification of newly formed polypeptides in plated eukaryotic cells. After the polypeptides are released from the ribosome, a chemically-tagged protein attaches covalently to lysine residues on the polypeptide chain, forming a modified polypeptide. When a barrel-shaped complex is added to the cytoplasm, the modified polypeptide lyses, resulting in individual amino acids and the chemically-tagged proteins. Which of the following post-translational modifications has most likely occurred?", "answer": "Ubiquitination", "options": {"A": "Acylation", "B": "Glycosylation", "C": "Phosphorylation", "D": "Carboxylation", "E": "Ubiquitination"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 38-year-old man presents to his physician with double vision persisting for a week. When he enters the exam room, the physician notes that the patient has a broad-based gait. The man’s wife informs the doctor that he has been an alcoholic for the last 5 years and his consumption of alcohol has increased significantly over the past few months. She also reports that he has become indifferent to his family members over time and is frequently agitated. She also says that his memory has been affected significantly, and when asked about a particular detail, he often recollects it incorrectly, though he insists that his version is the true one. On physical examination, his vital signs are stable, but when the doctor asks him where he is, he seems to be confused. His neurological examination also shows nystagmus. Which of the following options describes the earliest change in the pathophysiology of the central nervous system in this man?", "answer": "Decreased α-ketoglutarate dehydrogenase activity in astrocytes", "options": {"A": "Decreased α-ketoglutarate dehydrogenase activity in astrocytes", "B": "Increased extracellular concentration of glutamate", "C": "Increased astrocyte lactate", "D": "Breakdown of the blood-brain barrier", "E": "Increased fragmentation of deoxyribonucleic acid within the neurons"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 69-year-old man is brought by his son to the emergency department with weakness in his right arm and leg. The man insists that he is fine and blames his son for \"creating panic\". Four hours ago the patient was having tea with his wife when he suddenly dropped his teacup. He has had difficulty moving his right arm since then and cannot walk because his right leg feels stuck. He has a history of hypertension and dyslipidemia, for which he currently takes lisinopril and atorvastatin, respectively. He is allergic to aspirin and peanuts. A computerized tomography (CT) scan shows evidence of an ischemic stroke. Which medication would most likely prevent such attacks in this patient in the future?", "answer": "Clopidogrel", "options": {"A": "Abciximab", "B": "Alteplase", "C": "Urokinase", "D": "Celecoxib", "E": "Clopidogrel"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 70-year-old man presents to a medical clinic reporting blood in his urine and lower abdominal pain for the past few days. He is also concerned about urinary frequency and urgency. He states that he recently completed a cycle of chemotherapy for non-Hodgkin lymphoma. Which medication in the chemotherapy regimen most likely caused his symptoms?", "answer": "Cyclophosphamide", "options": {"A": "Cytarabine", "B": "Methotrexate", "C": "Rituximab", "D": "Cyclophosphamide", "E": "Prednisone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man presents to the emergency department after a dog bite. The patient was intoxicated and pulled the dog’s tail while it was eating. The dog belongs to his friend and is back at his friend’s house currently. Physical exam is notable for a dog bite on the patient’s right arm. The wound is irrigated and explored with no retained bodies found. A tetanus vaccination is administered. Which of the following is appropriate management of this patient?", "answer": "Administer amoxicillin-clavulanic acid", "options": {"A": "Administer amoxicillin-clavulanic acid", "B": "Administer the rabies vaccine and rabies immunoglobulin", "C": "Administer trimethoprim-sulfamethoxazole", "D": "Close the wound with sutures and discharge the patient", "E": "Discharge the patient with outpatient follow up"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 19-year-old woman, accompanied by her parents, presents after a one-week history of abnormal behavior, delusions, and unusual aggression. She denies fever, seizures or illicit drug use. Family history is negative for psychiatric illnesses. She was started on risperidone and sent home with her parents. Three days later, she is brought to the emergency department with fever and confusion. She is not verbally responsive. At the hospital, her temperature is 39.8°C (103.6°F), the blood pressure is 100/60 mm Hg, the pulse rate is 102/min, and the respiratory rate is 16/min. She is extremely diaphoretic and appears stiff. She has spontaneous eye-opening but she is not verbally responsive and she is not following commands. Laboratory studies show:\nSodium 142 mmol/L\nPotassium 5.0 mmol/L\nCreatinine 1.8 mg/dl\nCalcium 10.4 mg/dl\nCreatine kinase 9800 U/L\nWhite blood cells 14,500/mm3\nHemoglobin 12.9 g/dl\nPlatelets 175,000/mm3\nUrinalysis shows protein 1+, hemoglobin 3+ with occasional leukocytes and no red blood casts. What is the best first step in the management of this condition?", "answer": "Stop risperidone", "options": {"A": "Dantrolene", "B": "Intravenous hydration", "C": "Paracetamol", "D": "Stop risperidone", "E": "Switch risperidone to clozapine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old woman comes to the physician because of a 1-month history of double vision, difficulty climbing stairs, and weakness when trying to brush her hair. She reports that these symptoms are worse after she exercises and disappear after she rests for a few hours. Physical examination shows drooping of her right upper eyelid that worsens when the patient is asked to gaze at the ceiling for 2 minutes. There is diminished motor strength in the upper extremities. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Myasthenia gravis", "options": {"A": "Myasthenia gravis", "B": "Polymyositis", "C": "Amyotrophic lateral sclerosis", "D": "Guillain-Barré syndrome", "E": "Multiple sclerosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old male who recently immigrated to the United States from Asia is admitted to the hospital with dyspnea. Physical exam reveals a gray pseudomembrane in the patient's oropharynx along with lymphadenopathy. The patient develops myocarditis and expires on hospital day 5. Which of the following would have prevented this patient's presentation and decline?", "answer": "Circulating IgG against AB exotoxin", "options": {"A": "Increased CD4+ T cell count", "B": "Secretory IgA against viral proteins", "C": "Increased IgM preventing bacterial invasion", "D": "Circulating IgG against AB exotoxin", "E": "Improved IgE release from mast cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 12-year-old boy who recently emigrated from Pakistan presents with fever, muscle pain, and weakness of the trunk, abdomen, and legs. The patient’s mother says that he has not been vaccinated. Physical examination reveals fasciculation and flaccid paralysis of the lower limbs. A CSF analysis reveals lymphocytosis with normal glucose and protein levels. A throat swab reveals an RNA virus. Which of the following would most likely be destroyed by the virus in this patient?", "answer": "Anterior horn of the spinal cord", "options": {"A": "Basal ganglia", "B": "Posterior horn cells of the spinal cord", "C": "Myelin sheath of neurons", "D": "Muscle cells", "E": "Anterior horn of the spinal cord"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A researcher is studying the properties of an enzyme that adds phosphate groups to glucose. She discovers that the enzyme is present in most body tissues and is located in the cytoplasm of the cells expressing the enzyme. She decides to mix this enzyme under subphysiologic conditions with varying levels of glucose in order to determine the kinetic properties of the enzyme. Specifically, she adds increasing levels of glucose at a saturating concentration of phosphate and sees that the rate at which glucose becomes phosphorylated gets faster at higher levels of glucose. She observes that this rate approaches a maximum speed and calls this speed Y. She then determines the concentration of glucose that is needed to make the enzyme function at half the speed Y and calls this concentration X. Which of the following is most likely true about the properties of this enzyme?", "answer": "Low X and low Y", "options": {"A": "High X and high Y", "B": "High X and low Y", "C": "Low X and high Y", "D": "Low X and infinite Y", "E": "Low X and low Y"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old G2P2 female at 40 weeks gestation presents to the hospital following a rush of water that came from her vagina. She is 4 cm dilated and 80% effaced. Fetal heart tracing shows a pulse of 155/min with variable decelerations. About 12 hours after presentation, she gives birth to a 6 lb 15 oz baby boy with APGAR scores of 8 and 9 at 1 and 5 minutes, respectively. Which of the following structures is responsible for inhibition of female internal genitalia?", "answer": "Sertoli cells", "options": {"A": "Spermatogonia", "B": "Allantois", "C": "Syncytiotrophoblast", "D": "Sertoli cells", "E": "Leydig cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old woman presents to the emergency department complaining of palpitations, dry cough, and shortness of breath for 1 week. She immigrated to the United States from Korea at the age of 20. She says that her heart is racing and she has never felt these symptoms before. Her cough is dry and is associated with shortness of breath that occurs with minimal exertion. Her past medical history is otherwise unremarkable. She has no allergies and is not currently taking any medications. She is a nonsmoker and an occasional drinker. She denies illicit drug use. Her blood pressure is 100/65 mm Hg, pulse is 76/min, respiratory rate is 23/min, and temperature is 36.8°C (98.2°F). Her physical examination is significant for bibasilar lung crackles and a non-radiating, low-pitched, mid-diastolic rumbling murmur best heard at the apical region. In addition, she has jugular vein distention and bilateral pitting edema in her lower extremities. Which of the following best describes the infectious agent that led to this patient’s condition?", "answer": "A bacterium that induces complete lysis of the red cells of a blood agar plate with an oxygen-sensitive cytotoxin", "options": {"A": "A bacterium that induces partial lysis of red cells with hydrogen peroxide", "B": "A bacterium that induces complete lysis of the red cells of a blood agar plate with an oxygen-sensitive cytotoxin", "C": "A bacterium that induces heme degradation of the red cells of a blood agar plate", "D": "A bacterium that does not lyse red cells", "E": "A bacterium that requires an anaerobic environment to grow properly"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A male neonate is being examined by a pediatrician. His mother informs the doctor that she had a mild fever with rash, muscle pain, and swollen and tender lymph nodes during the second month of gestation. The boy was born at 39 weeks gestation via spontaneous vaginal delivery with no prenatal care. On physical examination, the neonate has normal vital signs. Retinal examination reveals the findings shown in the image. Which of the following congenital heart defects is most likely to be present in this neonate?", "answer": "Patent ductus arteriosus", "options": {"A": "Atrial septal defect", "B": "Ventricular septal defect", "C": "Tetralogy of Fallot", "D": "Patent ductus arteriosus", "E": "Double outlet right ventricle"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy is brought to the emergency department by his parents. He is lethargic and confused and has a severe headache, vomiting, and a high-grade fever since earlier that day. His mother reports that the child was doing well until 2 days ago when he developed a fever and green nasal discharge. The patient has a history of neonatal sepsis, meningococcemia at 18 months of age, and pneumococcal pneumonia at 2 and 3 years of age. His scheduled vaccinations are up to date. His blood pressure is 70/50 mm Hg, heart rate is 120/min, respiratory rate is 22/min, and temperature is 39.3°C (102.4°F). On examination, the child is lethargic and his skin is pale, with several petechiae over his buttocks. There is a purulent nasal discharge from both nostrils. The lungs are clear to auscultation bilaterally. Heart sounds are normal. There is marked neck rigidity. Cerebrospinal fluid analysis shows the following results:\nOpening pressure 100 mm H2O\nAppearance cloudy\nProtein 500 mg/dL (5 g/L)\nWhite blood cells 2500/μL (polymorphonuclear predominance)\nProtein 450 mg/dL (4.5 g/L)\nGlucose 31 mg/dL (1.7 mmol/L)\nCulture positive for N. meningitidis\nWhich of the following immunological processes is most likely to be impaired in this child?", "answer": "Formation of C5-9 complex", "options": {"A": "Production of IL-2 by Th1 cells", "B": "Activation of TCRs by MHC-II", "C": "Formation of C5-9 complex", "D": "Cleavage of C2 component of complement into C2a and C2b", "E": "Oxidative burst in macrophages"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 66-year-old woman with chronic obstructive pulmonary disease is brought to the emergency department because of fever, body aches, malaise, and a dry cough. She has smoked one pack of cigarettes daily for 30 years but quit smoking 1 year ago. She lives with her daughter and her granddaughter, who attends daycare. Her temperature is 38.1°C (101°F). Physical examination shows bilateral conjunctivitis, rhinorrhea, and erythematous tonsils without exudates. Further testing confirms infection with an enveloped orthomyxovirus. Administration of a drug with which of the following mechanisms of action is most appropriate?", "answer": "Inhibition of neuraminidase", "options": {"A": "Inhibition of nucleoside reverse transcriptase", "B": "Inhibition of DNA polymerase", "C": "Inhibition of proton translocation", "D": "Inhibition of neuraminidase", "E": "Inhibition of protease"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old woman undergoes hemithyroidectomy for treatment of localized, well-differentiated papillary thyroid carcinoma. The lesion is removed with clear margins. However, during the surgery, a structure lying directly adjacent to the superior thyroid artery at the upper pole of the thyroid lobe is damaged. This patient is most likely to experience which of the following symptoms?", "answer": "Voice pitch limitation", "options": {"A": "Voice pitch limitation", "B": "Ineffective cough", "C": "Weakness of shoulder shrug", "D": "Difficulty swallowing", "E": "Shortness of breath"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old man presents to the emergency room with persistent fever, nausea, and vomiting for the past 3 days. While waiting to be seen, he quickly becomes disoriented and agitated. Upon examination, he has visible signs of difficulty breathing with copious oral secretions and generalized muscle twitching. The patient’s temperature is 104°F (40°C), blood pressure is 90/64 mmHg, pulse is 88/min, and respirations are 18/min with an oxygen saturation of 90% on room air. When the nurse tries to place a nasal cannula, the patient becomes fearful and combative. The patient is sedated and placed on mechanical ventilation. Which of the following is a risk factor for the patient’s most likely diagnosis?", "answer": "Spelunking", "options": {"A": "Contaminated beef", "B": "Epiglottic cyst", "C": "Influenza vaccination", "D": "Mosquito bite", "E": "Spelunking"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 21-year-old man presents to the emergency department after sustaining a stab wound to the neck at a local farmer's market. The patient is otherwise healthy and is complaining of pain. The patient is able to offer the history himself. His temperature is 97.6°F (36.4°C), blood pressure is 120/84 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam demonstrates a 3 cm laceration 1 cm inferior to the mastoid process on the right side. The patient's breath sounds are clear and he is protecting his airway. No stridor or difficulty breathing is noted. Which of the following is the most appropriate next step in the management of this patient?", "answer": "CT angiogram", "options": {"A": "Arteriography", "B": "CT angiogram", "C": "Intubation", "D": "Observation and blood pressure monitoring", "E": "Surgical exploration"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 13-year-old girl presents to a medical office for the evaluation of a lump on the front of her neck. The patient denies pain, but states that the mass bothers her because “it moves when I swallow”. The physical examination reveals a midline neck mass that is above the hyoid bone but below the level of the mandible. The mass is minimally mobile and feels fluctuant without erythema. The patient is afebrile and all vital signs are stable. A complete blood count and thyroid function tests are performed and are within normal limits. What is the most likely cause of this patient’s presentation?", "answer": "Cyst formation in a persistent thyroglossal duct", "options": {"A": "Persistent thyroid tissue at the tongue base", "B": "Deletion of the 22q11 gene", "C": "Thyroid hyperplasia due to iodine deficiency", "D": "Cyst formation in a persistent thyroglossal duct", "E": "Lymph node enlargement"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old woman with a history of Crohn disease presents for a follow-up appointment. She says that lately, she has started to notice difficulty walking. She says that some of her friends have joked that she appears to be walking as if she was drunk. Past medical history is significant for Crohn disease diagnosed 2 years ago, managed with natalizumab for the past year because her intestinal symptoms have become severe and unresponsive to other therapies. On physical examination, there is gait and limb ataxia present. Strength is 4/5 in the right upper limb. A T1/T2 MRI of the brain is ordered and is shown. Which of the following is the most likely diagnosis?", "answer": "Progressive multifocal encephalopathy (PML)", "options": {"A": "Sporadic Creutzfeldt-Jakob disease (sCJD)", "B": "Variant Creutzfeldt-Jakob disease (vCJD)", "C": "Subacute sclerosing panencephalitis (SSPE)", "D": "Progressive multifocal encephalopathy (PML)", "E": "West Nile encephalitis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old G1 at 10 weeks gestation based on her last menstrual period is brought to the emergency department by her husband due to sudden vaginal bleeding. She says that she has mild lower abdominal cramps and is feeling dizzy and weak. Her blood pressure is 100/60 mm Hg, the pulse is 100/min, and the respiration rate is 15/min. She says that she has had light spotting over the last 3 days, but today the bleeding increased markedly and she also noticed the passage of clots. She says that she has changed three pads since the morning. She has also noticed that the nausea she was experiencing over the past few days has subsided. The physician examines her and notes that the cervical os is open and blood is pooling in the vagina. Products of conception can be visualized in the os. The patient is prepared for a suction curettage. Which of the following is the most likely cause for the pregnancy loss?", "answer": "Chromosomal abnormalities", "options": {"A": "Sexually transmitted disease (STD)", "B": "Rh immunization", "C": "Antiphospholipid syndrome", "D": "Chromosomal abnormalities", "E": "Trauma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-month-old boy is brought to a medical office by his mother. The mother states that the boy has been very fussy and has not been feeding recently. The mother thinks the baby has been gaining weight despite not feeding well. The boy was delivered vaginally at 39 weeks gestation without complications. On physical examination, the boy is noted to be crying in his mother’s arms. There is no evidence of cyanosis, and the cardiac examination is within normal limits. The crying intensifies when the abdomen is palpated. The abdomen is distended with tympany in the left lower quadrant. You suspect a condition caused by the failure of specialized cells to migrate. What is the most likely diagnosis?", "answer": "Hirschsprung disease", "options": {"A": "Meckel diverticulum", "B": "DiGeorge syndrome", "C": "Pyloric stenosis", "D": "Duodenal atresia", "E": "Hirschsprung disease"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old man seeks evaluation at a medical office due to leg pain while walking. He says the pain starts in his buttocks and extends to his thighs and down to his calves. Previously, the pain resolved with rest, but the pain now persists in his feet, even during rest. His past medical history is significant for diabetes mellitus, hypertension, and cigarette smoking. The vital signs are within normal limits. The physical examination shows an atrophied leg with bilateral loss of hair. Which of the following is the most likely cause of this patient’s condition?", "answer": "Narrowing and calcification of vessels", "options": {"A": "Decreased permeability of endothelium", "B": "Narrowing and calcification of vessels", "C": "Peripheral emboli formation", "D": "Thrombus formation", "E": "Weakening of vessel wall"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man presents to the emergency department with chest pain radiating to his left jaw and arm. He states that he had experienced similar symptoms when playing basketball. The medical history is significant for diabetes mellitus, hypertension, and GERD, for which he takes metformin, hydrochlorothiazide, and pantoprazole, respectively. The blood pressure is 150/90 mm Hg, the pulse is 100/min, and the respirations are 15/min. The ECG reveals ST elevation in leads V3-V6. He is hospitalized for an acute MI and started on treatment. The next day he complains of dizziness and blurred vision. Repeat vital signs were as follows: blood pressure 90/60 mm Hg, pulse 72/min, and respirations 12/min. The laboratory results were as follows:\nSerum chemistry\nSodium 143 mEq/L\nPotassium 4.1 mEq/L\nChloride 98 mEq/L\nBicarbonate 22 mEq/L\nBlood urea nitrogen  26 mg/dL\nCreatinine 2.3 mg/dL\nGlucose 120 mg/dL\nWhich of the following drugs is responsible for this patient’s lab abnormalities?", "answer": "Lisinopril", "options": {"A": "Digoxin", "B": "Pantoprazole", "C": "Lisinopril", "D": "Atorvastatin", "E": "Nitroglycerin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman is brought to the hospital by her boyfriend. She has had three days of fever and headache followed by one day of worsening confusion and hallucinations. She also becomes agitated when offered water. Her temperature is 101°F (38.3°C). Two months prior to presentation, the couple was camping and encountered bats in their cabin. In addition to an injection shortly after exposure, what would have been the most effective treatment for this patient?", "answer": "A killed vaccine within ten days of exposure", "options": {"A": "A toxoid vaccine within ten days of exposure", "B": "A killed vaccine within ten days of exposure", "C": "Oseltamivir within one week of exposure", "D": "Venom antiserum within hours of exposure", "E": "Doxycycline for one month after exposure"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old man comes to the physician for an examination prior to a scheduled cholecystectomy. He has hypertension treated with hydrochlorothiazide. His mother had chronic granulomatous disease of the lung. He works in a glass manufacturing plant. He has smoked two packs of cigarettes daily for 38 years. His vital signs are within normal limits. Examination shows no abnormalities. Laboratory studies are within the reference range. An x-ray of the chest is shown. Which of the following is the most appropriate next step in management?", "answer": "Request previous chest x-ray", "options": {"A": "Perform arterial blood gas analysis", "B": "Perform CT-guided biopsy", "C": "Perform diffusion capacity of the lung for carbon monoxide", "D": "Measure angiotensin-converting enzyme", "E": "Request previous chest x-ray"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "You are examining a 3-day-old newborn who was delivered vaginally without any complications. The newborn presents with vomiting, hyperventilation, lethargy, and seizures. Blood work demonstrates hyperammonemia, elevated glutamine levels, and decreased blood urea nitrogen. A CT scan demonstrates cerebral edema. Defects in which of the following enzymes would result in a clinical presentation similar to this infant?", "answer": "Carbamoyl phosphate synthetase I", "options": {"A": "Phenylalanine hydroxylase", "B": "Branched-chain ketoacid dehydrogenase", "C": "Homogentisate oxidase", "D": "Cystathionine synthase", "E": "Carbamoyl phosphate synthetase I"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 48-year-old man with HIV comes to the physician because of skin lesions over his face and neck for 2 weeks. They are not itchy or painful. He does not have fever or a sore throat. He was treated for candidal esophagitis 3 months ago. He is sexually active with his wife, who knows of his condition, and uses condoms consistently. He is currently receiving triple antiretroviral therapy with lamivudine, abacavir, and efavirenz. He is 175 cm (5 ft 9 in) tall and weighs 58 kg (128 lb); BMI is 18.8 kg/m2. Examination shows multiple skin colored papules over his face and neck with a dimpled center. Cervical lymphadenopathy is present. The remainder of the examination is unremarkable. His hemoglobin concentration is 12.1 g/dL, leukocyte count is 4,900/mm3, and platelet count is 143,000/mm3; serum studies and urinalysis show no abnormalities. CD4+ T-lymphocyte count is 312/mm3 (normal ≥ 500). Which of the following is the most likely cause of this patient's findings?", "answer": "Poxvirus", "options": {"A": "A herpesvirus", "B": "Bartonella", "C": "Papillomavirus", "D": "Poxvirus", "E": "Coccidioides\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man comes to the physician because of fatigue and worsening abdominal pain for 4 weeks. He also reports excessive night sweats and a 5.4-kg (12-lb) weight loss during this time. He has a neck swelling for 4 days. Physical examination shows a nontender, enlarged, and fixed supraclavicular lymph node. There is splenomegaly. A CT scan of the thorax and abdomen shows massively enlarged axillary, mediastinal, and cervical lymph nodes. Analysis of an excised cervical lymph node shows lymphocytes with a high proliferative index that stain positive for CD20. Which of the following is the most likely diagnosis?", "answer": "Diffuse large B-cell lymphoma", "options": {"A": "Adult T-cell lymphoma", "B": "Burkitt lymphoma", "C": "Follicular lymphoma", "D": "Diffuse large B-cell lymphoma", "E": "Hodgkin lymphoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 26-year-old G1P0 woman at 32-weeks gestation presents for follow-up ultrasound. She was diagnosed with gestational diabetes during her second trimester, but admits to poor glucose control and non-adherence to insulin therapy. Fetal ultrasound reveals an asymmetric, enlarged interventricular septum, left ventricular outflow tract obstruction, and significantly reduced ejection fraction. Which of the following is the most appropriate step in management after delivery?", "answer": "Medical management", "options": {"A": "Emergent open fetal surgery", "B": "Cardiac magnetic resonance imaging", "C": "Cardiac catheterization", "D": "Chest radiograph", "E": "Medical management"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A recent study attempted to analyze whether increased \"patient satisfaction\" driven healthcare resulted in increased hospitalization. In this hospital, several of the wards adopted new aspects of \"patient satisfaction\" driven healthcare, whereas the remainder of the hospital continued to use existing protocols. Baseline population characteristics and demographics were collected at the start of the study. At the end of the following year, hospital use was assessed and compared between the two groups. Which of the following best describes this type of study?", "answer": "Prospective cohort", "options": {"A": "Retrospective cohort", "B": "Prospective cohort", "C": "Retrospective case-control", "D": "Prospective case-control", "E": "Cross-sectional study"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A new screening test utilizing a telemedicine approach to diagnosing diabetic retinopathy has been implemented in a diabetes clinic. An ophthalmologist’s exam was also performed on all patients as the gold standard for diagnosis. In a pilot study of 500 patients, the screening test detected the presence of diabetic retinopathy in 250 patients. Ophthalmologist exam confirmed a diagnosis of diabetic retinopathy in 200 patients who tested positive in the screening test, as well as 10 patients who tested negative in the screening test. What is the sensitivity, specificity, positive predictive value, and negative predictive value of the screening test?", "answer": "Sensitivity = 95%, Specificity = 83%, PPV = 80%, NPV = 96%", "options": {"A": "Sensitivity = 83%, Specificity = 95%, PPV = 80%, NPV = 96%", "B": "Sensitivity = 83%, Specificity = 95%, PPV = 96%, NPV = 80%", "C": "Sensitivity = 95%, Specificity = 83%, PPV = 96%, NPV = 80%", "D": "Sensitivity = 80%, Specificity = 95%, PPV = 96%, NPV = 83%", "E": "Sensitivity = 95%, Specificity = 83%, PPV = 80%, NPV = 96%"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A healthy 22-year-old male participates in a research study you are leading to compare the properties of skeletal and cardiac muscle. You conduct a 3-phased experiment with the participant. In the first phase, you get him to lift up a 2.3 kg (5 lb) weight off a table with his left hand. In the second phase, you get him to do 20 burpees, taking his heart rate to 150/min. In the third phase, you electrically stimulate his gastrocnemius with a frequency of 50 Hz. You are interested in the tension and electrical activity of specific muscles as follows: Biceps in phase 1, cardiac muscle in phase 2, and gastrocnemius in phase 3. What would you expect to be happening in the phases and the respective muscles of interest?", "answer": "Increase of tension in all phases", "options": {"A": "Recruitment of small motor units at the start of experiments 1 and 2", "B": "Increase of tension in experiments 2 and 3, with the same underlying mechanism", "C": "Recruitment of large motor units followed by small motor units in experiment 1", "D": "Fused tetanic contraction at the end of all three experiments", "E": "Increase of tension in all phases"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old male comes into your office two days after falling during a pick up basketball game. The patient states that the lateral aspect of his knee collided with another player's knee. On exam, the patient's right knee appears the same size as his left knee without any swelling or effusion. The patient has intact sensation and strength in both lower extremities. The patient's right knee has no laxity upon varus stress test, but is more lax upon valgus stress test when compared to his left knee. Lachman's test and posterior drawer test both have firm endpoints without laxity. Which of the following structures has this patient injured?", "answer": "Medial collateral ligament", "options": {"A": "Posterior cruciate ligament", "B": "Anterior cruciate ligament", "C": "Medial collateral ligament", "D": "Lateral collateral ligament", "E": "Medial meniscus"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old boy is brought to the physician because of swelling around his eyes for 4 days. The swelling is most severe in the morning and milder by bedtime. Ten days ago, he had a sore throat that resolved spontaneously. His temperature is 37°C (98.6°F), pulse is 103/min, and blood pressure is 88/52 mm Hg. Examination shows 3+ pitting edema of the lower extremities and periorbital edema. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 15.3 g/dL\nLeukocyte count 10,500/mm3\nPlatelet count 480,000/mm3\nSerum\nUrea nitrogen 36 mg/dL\nGlucose 67 mg/dL\nCreatinine 0.8 mg/dL\nAlbumin 2.6 mg/dL\nUrine\nBlood negative\nGlucose negative\nProtein 4+\nRBC none\nWBC 0–1/hpf\nFatty casts numerous\nProtein/creatinine ratio 6.8 (N ≤0.2)\nSerum complement concentrations are within the reference ranges. Which of the following is the most appropriate next step in management?\"", "answer": "Prednisone therapy", "options": {"A": "Enalapril therapy", "B": "Furosemide therapy", "C": "Anti-streptolysin O levels", "D": "Prednisone therapy", "E": "Cyclosporine therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 18-year-old man comes to the clinic with his mom for “pins and needles” of both of his arms. He denies any past medical history besides a recent anterior cruciate ligament (ACL) tear that was repaired 1 week ago. The patient reports that the paresthesias are mostly located along the posterior forearms, left more than the right. What physical examination finding would you expect from this patient?", "answer": "Loss of wrist extension", "options": {"A": "Loss of arm abduction", "B": "Loss of finger abducton", "C": "Loss of forearm flexion and supination", "D": "Loss of thumb opposition", "E": "Loss of wrist extension"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 9-year-old girl is resuscitated after the administration of an erroneous dose of intravenous phenytoin for recurrent seizures. This incident is reported to the authorities. A thorough investigation reveals various causative factors leading to the event. One important finding is a verbal misunderstanding of the dose of phenytoin between the ordering senior resident and the receiving first-year resident during the handover of the patient. To minimize the risk of this particular error in the future, the most appropriate management is to implement which of the following?", "answer": "Closed-loop communication", "options": {"A": "Closed-loop communication", "B": "Near miss", "C": "Root cause analysis", "D": "Sentinel event", "E": "Two patient identifiers"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "You are the team physician for an NBA basketball team. On the morning of an important playoff game, an EKG of a star player, Mr. P, shows findings suspicious for hypertrophic cardiomyopathy (HCM). Mr. P is an otherwise healthy, fit, professional athlete.\n\nThe playoff game that night is the most important of Mr. P's career. When you inform the coach that you are thinking of restricting Mr. P's participation, he threatens to fire you. Later that day you receive a phone call from the owner of the team threatening a lawsuit should you restrict Mr. P's ability to play. Mr. P states that he will be playing in the game \"if it's the last thing I do.\"\n\nWhich of the following is the most appropriate next step?", "answer": "Educate Mr. P about the risks of HCM", "options": {"A": "Consult with a psychiatrist to have Mr. P committed", "B": "Call the police and have Mr. P arrested", "C": "Allow Mr. P to play against medical advice", "D": "Educate Mr. P about the risks of HCM", "E": "Schedule a repeat EKG for the following morning"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old woman presents to the emergency department complaining of generalized malaise, weakness, headache, nausea, vomiting, and diarrhea; she last felt well roughly two days ago. She is otherwise healthy, and takes no medications. Her vital signs are: T 38.0, HR 96 beats per minute, BP 110/73, and O2 sat 96% on room air. Examination reveals a somewhat ill-appearing woman; she is drowsy but arousable and has no focal neurological deficits. Initial laboratory studies are notable for hematocrit 26%, platelets of 80,000/mL, and serum creatinine of 1.5 mg/dL. Which of the following is the most appropriate treatment at this time?", "answer": "Plasma exchange therapy", "options": {"A": "High-dose glucocorticoids", "B": "Cyclophosphamide and rituximab", "C": "Vancomycin and cefepime", "D": "Plasma exchange therapy", "E": "Urgent laparoscopic splenectomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-week-old infant born at 36 weeks' gestation is brought to the physician for a well-child examination. Her mother reports that she previously breastfed her for 15 minutes every 2 hours but now feeds her for 40 minutes every 4 hours. The infant has six wet diapers and two stools daily. She currently weighs 3500 g (7.7 lb) and is 52 cm (20.4 in) in length. Vital signs are with normal limits. Cardiopulmonary examination shows a grade 4/6 continuous murmur heard best at the left infraclavicular area. After confirming the diagnosis via echocardiography, which of the following is the most appropriate next step in management of this patient?", "answer": "Indomethacin infusion", "options": {"A": "Prostaglandin E1 infusion", "B": "Indomethacin infusion", "C": "Surgical ligation", "D": "Reassurance and follow-up", "E": "Percutaneous surgery"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 51-year-old woman comes to the physician because of a 1-day history of right flank pain and bloody urine. Over the past 2 weeks, she has also developed progressive lower extremity swelling and a 3-kg (7-lb) weight gain. She has a history of chronic hepatitis B infection, which was diagnosed 10 years ago. She frequently flies from California to New York for business. She appears fatigued. Her pulse is 98/min, respirations are 18/min, and blood pressure is 135/75 mm Hg. Examination shows periorbital edema, a distended abdomen, and 2+ edema of the lower extremities. The lungs are clear to auscultation. A CT scan of the abdomen shows a nodular liver with ascites, a large right kidney with abundant collateral vessels, and a filling defect in the right renal vein. Urinalysis shows 4+ protein, positive glucose, and fatty casts. Which of the following is the most likely underlying cause of this patient's renal vein findings?", "answer": "Loss of antithrombin III", "options": {"A": "Acquired factor VIII deficiency", "B": "Loss of antithrombin III", "C": "Impaired estrogen degradation", "D": "Antiphospholipid antibodies", "E": "Paraneoplastic erythropoietin production"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man comes to the physician for a follow-up evaluation of chronic, retrosternal chest pain. The pain is worse at night and after heavy meals. He has taken oral pantoprazole for several months without any relief of his symptoms. Esophagogastroduodenoscopy shows ulcerations in the distal esophagus and a proximally dislocated Z-line. A biopsy of the distal esophagus shows columnar epithelium with goblet cells. Which of the following microscopic findings underlie the same pathomechanism as the cellular changes seen in this patient?", "answer": "Squamous epithelium in the bladder", "options": {"A": "Pseudostratified columnar epithelium in the bronchi", "B": "Squamous epithelium in the bladder", "C": "Paneth cells in the duodenum", "D": "Branching muscularis mucosa in the jejunum", "E": "Disorganized squamous epithelium in the endocervix"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 37-year-old woman comes to the physician because of a 6-month history of weight loss, bloating, and diarrhea. She does not smoke or drink alcohol. Her vital signs are within normal limits. She is 173 cm (5 ft 8 in) tall and weighs 54 kg (120 lb); BMI is 18 kg/m2. Physical examination shows bilateral white spots on the temporal half of the conjunctiva, dry skin, and a hard neck mass in the anterior midline that does not move with swallowing. Urinalysis after a D-xylose meal shows an increase in renal D-xylose excretion. Which of the following is most likely to have prevented this patient's weight loss?", "answer": "Pancreatic enzyme replacement", "options": {"A": "Gluten-free diet", "B": "Pancreatic enzyme replacement", "C": "Tetracycline therapy", "D": "Mesalamine therapy", "E": "Lactose-free diet"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man presents for a routine checkup. Past medical history is remarkable for stage 1 systemic hypertension and hepatitis A infection diagnosed 10 years ago. He takes aspirin, rosuvastatin, enalapril daily, and a magnesium supplement every once in a while. He is planning to visit Ecuador for a week-long vacation and is concerned about malaria prophylaxis before his travel. The physician advised taking 1 primaquine pill every day while he is there and for 7 consecutive days after leaving Ecuador. On the third day of his trip, the patient develops an acute onset headache, dizziness, shortness of breath, and fingertips and toes turning blue. His blood pressure is 135/80 mm Hg, heart rate is 94/min, respiratory rate is 22/min, temperature is 36.9℃ (98.4℉), and blood oxygen saturation is 97% in room air. While drawing blood for his laboratory workup, the nurse notes that his blood has a chocolate brown color. Which of the following statements best describes the etiology of this patient’s most likely condition?", "answer": "It is a type B adverse drug reaction.", "options": {"A": "The patient’s condition is due to consumption of water polluted with nitrates.", "B": "This condition resulted from primaquine overdose.", "C": "The patient had pre-existing liver damage caused by viral hepatitis.", "D": "The condition developed because of his concomitant use of primaquine and magnesium supplement.", "E": "It is a type B adverse drug reaction."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old woman, gravida 2, para 1, at 32 weeks' gestation comes to the emergency department for sudden leakage of clear vaginal fluid. Her pregnancy has been uncomplicated. Her first child was born at term by vaginal delivery. She has no history of serious illness. She does not drink alcohol or smoke cigarettes. Current medications include vitamin supplements. Her temperature is 37.2°C (98.9°F), pulse is 70/min, respirations are 18/min, and blood pressure is 128/82 mm Hg. Speculum examination demonstrates clear fluid in the cervical canal. The fetal heart rate is reactive at 160/min with no decelerations. Tocometry shows uterine contractions. Nitrazine testing is positive. She is started on indomethacin. Which of the following is the most appropriate next step in management?", "answer": "Administer betamethasone and ampicillin", "options": {"A": "Administer betamethasone, ampicillin, and proceed with cesarean section", "B": "Administer ampicillin and perform amnioinfusion", "C": "Administer ampicillin and test amniotic fluid for fetal lung maturity", "D": "Administer betamethasone and ampicillin", "E": "Administer betamethasone, ampicillin, and proceed with induction of labor"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old girl is brought to the emergency department by her friends who say that she took a whole bottle of her mom’s medication. They do not know which medication it was she ingested. The patient is slipping in and out of consciousness and is unable to offer any history. Her temperature is 39.6°C (103.2°F), the heart rate is 135/min, the blood pressure is 178/98 mm Hg, and the respiratory rate is 16/min. On physical examination, there is significant muscle rigidity without tremor or clonus. Which of the following is the best course of treatment for this patient?", "answer": "Dantrolene", "options": {"A": "Naloxone", "B": "Dantrolene", "C": "Fenoldopam", "D": "Cyproheptadine", "E": "Flumazenil"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old woman is brought to the emergency department because of fever, productive cough, and dyspnea for 3 days. She has had upper back pain for 3 months, which is worse after activity. She takes ibuprofen for pain relief. She has no history of smoking. The temperature is 39.5°C (103.1°F), the blood pressure is 100/70 mm Hg, the pulse is 95/min, and the respirations are 22/min. Lung auscultation shows rales in the left lower lobe area. Painful lymph nodes (1 × 1 cm) are palpated in the left axillary and cervical regions. There is point tenderness along several thoracic vertebrae. Laboratory studies are pending. A skull X-ray and lung window thoracic computed tomography scan are shown. Which of the following disorders most likely played a role in this patient’s acute condition?", "answer": "Multiple myeloma", "options": {"A": "Metastatic breast cancer", "B": "Multiple myeloma", "C": "Non-small cell lung cancer", "D": "Paget’s disease", "E": "Primary hyperparathyroidism"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old woman presents to the emergency department with a 2-day history of severe blistering. She says that she woke up 2 days ago with a number of painful blisters in her mouth and has since been continuing to develop blisters of her cutaneous skin all over her body and the mucosa of her mouth. She has no past medical history and has never experienced these symptoms before. Physical exam reveals a diffuse vesicular rash with painful, flaccid blisters that separate easily with gentle rubbing. The function of which of the following proteins is most likely disrupted in this patient?", "answer": "Cadherin", "options": {"A": "Cadherin", "B": "Collagen", "C": "Integrin", "D": "Keratin", "E": "T-cell receptor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-week-old boy is brought to the emergency department by his parents because of a 3-day history of progressive lethargy and difficulty feeding. He was born at term and did not have difficulty feeding previously. His temperature is 39.4°C (103°F), pulse is 220/min, respirations are 45/min, and blood pressure is 50/30 mm Hg. Pulse oximetry on 100% oxygen shows an oxygen saturation of 97%. Examination shows dry mucous membranes, delayed capillary refill time, and cool skin with poor turgor. Despite multiple attempts by the nursing staff, they are unable to establish peripheral intravenous access. Which of the following is the most appropriate next step in management?", "answer": "Intraosseous cannulation", "options": {"A": "Rapid sequence intubation", "B": "Intramuscular epinephrine", "C": "Internal jugular vein cannulation", "D": "Intraosseous cannulation", "E": "Ultrasound-guided antecubital vein cannulation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 10-year-old boy is brought to the emergency room by his mother 5 hours after the onset of abdominal pain and nausea. Over the past 2 weeks, he has also had progressive abdominal pain and a 4-kg (8.8-lb) weight loss. The mother reports that her son has been drinking more water than usual during this period. Last week he wet his bed three times despite being completely toilet-trained since 3 years of age. His temperature is 37.8°C (100°F), pulse is 128/min, respirations are 35/min, and blood pressure is 95/55 mm Hg. He appears lethargic. Physical examination shows deep and labored breathing and dry mucous membranes. The abdomen is soft, and there is diffuse tenderness to palpation with no guarding or rebound. Serum laboratory studies show:\nNa+ 133 mEq/L\nK+ 5.9 mEq/L\nCl- 95 mEq/L\nHCO3- 13 mEq/L\nUrea nitrogen 25 mg/dL\nCreatinine 1.0 mg/dL\nUrine dipstick is positive for ketones and glucose. Further evaluation is most likely to reveal which of the following?\"", "answer": "Decreased total body potassium", "options": {"A": "Decreased total body potassium", "B": "Increased total body sodium", "C": "Increased arterial pCO2", "D": "Hypervolemia", "E": "Serum glucose concentration > 600 mg/dL"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 70-year-old Caucasian male visits your office regularly for treatment of New York Heart association class IV congestive heart failure. Which of the following medications would you add to this man's drug regimen in order to improve his overall survival?", "answer": "Spironolactone", "options": {"A": "Spironolactone", "B": "Amiloride", "C": "Hydrochlorothiazide", "D": "Furosemide", "E": "Acetazolamide"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Several hours after vaginal delivery, a male newborn delivered at full-term develops tachycardia and tachypnea. His blood pressure is within normal limits. Pulse oximetry on room air shows an oxygen saturation of 79% in the right hand and 61% in the left foot. Physical examination shows bluish discoloration of the face and trunk, supraclavicular and intercostal retractions, and a machine-like murmur over the precordium. Bedside echocardiography shows pulmonary and systemic circulation are in parallel rather than in series. What is the most appropriate pharmacotherapy for this patient?", "answer": "Alprostadil", "options": {"A": "Sildenafil", "B": "Alprostadil", "C": "Metoprolol", "D": "Indomethacin", "E": "Dopamine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old male visits his pediatrician for a check-up. His height corresponds to the 99th percentile for his age, and pubic hair is present upon physical examination. Serum renin and potassium levels are high, as is 17-hydroxyprogesterone. Which of the following is likely deficient in this patient?", "answer": "21-hydroxylase", "options": {"A": "17a-hydroxylase", "B": "11ß-hydroxylase", "C": "21-hydroxylase", "D": "Aromatase", "E": "5a-reductase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 41-year-old African American woman presents with her husband to her primary care doctor for evaluation of depression and anxiety. She reports a 2-week history of rapid onset sadness with no clear inciting factor. She is accompanied by her husband who notes that she has had at least three similar episodes that have occurred over the past two years. He also notes that she has been “more emotional” lately and seems confused throughout the day. She has had to leave her job as a librarian at her child’s elementary school. Her past medical history is notable for two diagnostic laparoscopies for recurrent episodes of abdominal pain of unknown etiology. Her family history is notable for psychosis in her mother and maternal grandfather. Her temperature is 99°F (37.2°C), blood pressure is 125/75 mmHg, pulse is 75/min, and respirations are 17/min. On exam, she is disheveled and appears confused and disoriented. Her attention span is limited and she exhibits emotional lability. This patient’s condition is most likely due to a defect in an enzyme that metabolizes which of the following compounds?", "answer": "Porphobilinogen", "options": {"A": "Aminolevulinic acid", "B": "Coproporphyrinogen III", "C": "Hydroxymethylbilane", "D": "Porphobilinogen", "E": "Protoporphyrin IX"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old woman presents to her primary care physician for a general wellness appointment. The patient has no complaints currently and just wants to be sure that she is in good health. The patient has a past medical history of asthma, hypertension, and anxiety. Her current medications include albuterol, fluticasone, hydrochlorothiazide, lisinopril, and fexofenadine. Her temperature is 99.5°F (37.5°C), blood pressure is 165/95 mmHg, pulse is 70/min, respirations are 15/min, and oxygen saturation is 98% on room air. On exam, you note a healthy young woman with a lean habitus. Cardiac exam reveals a S1 and S2 heart sound with a normal rate. Pulmonary exam is clear to auscultation bilaterally with good air movement. Abdominal exam reveals a bruit, normoactive bowel sounds, and an audible borborygmus. Neurological exam reveals cranial nerves II-XII as grossly intact with normal strength and reflexes in the upper and lower extremities. Which of the following is the best next step in management?", "answer": "Ultrasound with doppler", "options": {"A": "Raise lisinopril dose", "B": "Add furosemide", "C": "Ultrasound with doppler", "D": "CT of the abdomen", "E": "No additional management needed"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old man comes to the emergency department because of a 10-day history of right upper quadrant abdominal pain. He has also been feeling tired and nauseous for the past 6 weeks. On examination, scleral icterus is present. Abdominal examination shows tenderness to palpation in the right upper quadrant. The liver edge is palpated 2 cm below the right costal margin. Laboratory studies show:\nAspartate aminotransferase 1780 U/L\nAlanine aminotransferase 2520 U/L\nHepatitis A IgM antibody Negative\nHepatitis B surface antigen Negative\nHepatitis B surface antibody Negative\nHepatitis B core IgM antibody Positive\nHepatitis C antibody Positive\nHepatitis C RNA Negative\nWhich of the following is the best course of action for this patient?\"", "answer": "Supportive therapy", "options": {"A": "Ribavirin and interferon", "B": "Supportive therapy", "C": "Tenofovir", "D": "Emergency liver transplantation", "E": "Pegylated interferon-alpha"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old boy who recently emigrated from Nigeria is brought to the emergency department because of a 2-day history of lower leg weakness, swallowing difficulty, and drooling of saliva. He has not yet received any childhood vaccinations. Two days after admission, the patient develops shortness of breath. Pulse oximetry shows an oxygen saturation of 64%. Despite resuscitative efforts, the patient dies of respiratory failure. At autopsy, examination of the spinal cord shows destruction of the anterior horn cells. Neurological examination of this patient would have most likely shown which of the following findings?", "answer": "Hyporeflexia", "options": {"A": "Positive Babinski sign", "B": "Hyporeflexia", "C": "Sensory loss", "D": "Myoclonus", "E": "Pronator drift"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old woman is brought to the urgent care clinic by her husband. She complains of numbness around her lips and a tingling sensation in her hands and feet. She underwent near-total thyroidectomy for an enlarged thyroid gland a month ago. Vital signs include: blood pressure is 130/70 mm Hg, pulse is 72/min, respiratory rate is 16/min, and temperature is 37.0°C (98.6°F). A surgical incision scar is present in the anterior aspect of the neck. The attending physician inflates the blood pressure cuff above 150 mm Hg and observes the patient a couple of minutes while measuring her blood pressure. The patient develops sudden stiffness and tingling in her hand. Blood test results are as follows:\nHemoglobin (Hb%) 10.2 g/dL\nWhite blood cell count 7000/mm3\nPlatelet count 160,000/mm3\nCalcium, serum (Ca2+) 6.0 mg/dL\nAlbumin 4 g/dL\nAlanine aminotransferase (ALT), serum 15 U/L\nAspartate aminotransferase (AST), serum 8 U/L\nSerum creatinine 0.5 mg/dL\nUrea 27 mg/dL\nSodium 137 mEq/L\nPotassium 4.5 mEq/L\nMagnesium 2.5 mEq/L\nUrinalysis shows no white or red blood cells and leukocyte esterase is negative. Which of the following is the next best step in the management of this patient?", "answer": "Serum parathyroid hormone (PTH) level", "options": {"A": "CT scan abdomen with pancreatic protocol", "B": "Thyroid function tests", "C": "Serum vitamin D level", "D": "24-hour urinary calcium", "E": "Serum parathyroid hormone (PTH) level"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A woman with coronary artery disease is starting to go for a walk. As she begins, her heart rate accelerates from a resting pulse of 60 bpm until it reaches a rate of 120 bpm, at which point she begins to feel a tightening in her chest. She stops walking to rest and the tightening resolves. This has been happening to her consistently for the last 6 months. Which of the following is a true statement?", "answer": "Increasing the heart rate decreases the relative amount of time spent during diastole", "options": {"A": "Increasing the heart rate increases the amount of time spent during each cardiac cycle", "B": "Increasing the heart rate decreases the relative amount of time spent during diastole", "C": "Perfusion of the myocardium takes place primarily during systole", "D": "Perfusion of the myocardium takes place equally throughout the cardiac cycle", "E": "This patient's chest pain is indicative of transmural ischemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old female presents to her physician for evaluation of a vaginal discharge, itching, and irritation. She recently started a new relationship with her boyfriend, who is her only sexual partner. He does not report any genitourinary symptoms. She takes oral contraceptives and does not use  barrier contraception. The medical history is unremarkable. The vital signs are within normal limits. A gynecologic examination reveals a thin, yellow, frothy vaginal discharge with a musty, unpleasant odor and numerous punctate red maculae on the ectocervix. The remainder of the exam is normal. Which of the following organisms will most likely be revealed on wet mount microscopy?", "answer": "Motile round or oval-shaped microorganisms", "options": {"A": "Budding yeasts cells and/or pseudohyphae", "B": "Epithelial cells covered by numerous bacterial cells", "C": "Motile round or oval-shaped microorganisms", "D": "Numerous rod-shaped bacteria", "E": "Chains of cocci"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 53-year-old woman with hypertension and hyperlipidemia comes to the physician because of generalized reddening of her skin and itching for the past 2 weeks. Her symptoms occur every evening before bedtime and last for about 30 minutes. Three months ago, atorvastatin was stopped after she experienced progressively worsening neck and back pain. Statin therapy was reinitiated at lower doses 3 weeks ago but had to be stopped again after her musculoskeletal symptoms recurred. Her menses occur irregularly at 2–3 month intervals and last for 3–4 days. She has smoked one pack of cigarettes daily for the past 30 years. Her current medications include lisinopril and niacin. Her brother died of colonic adenocarcinoma, and her father died of small cell lung cancer. She is 169 cm (5 ft 6 in) tall and weighs 83 kg (183 lb); BMI is 29 kg/m2. Her vital signs are within normal limits. Physical examination shows no abnormalities. Serum lipid studies show:\nTotal cholesterol 247 mg/dL\nHDL-cholesterol 39 mg/dL\nLDL-cholesterol 172 mg/dL\nTriglycerides 152 mg/dL\nWhich of the following is the most appropriate next step in management?\"", "answer": "Administer ibuprofen", "options": {"A": "Administer ibuprofen", "B": "Measure urine hydroxyindoleacetic acid levels", "C": "Measure urine metanephrine levels", "D": "Switch lisinopril to hydrochlorothiazide", "E": "Switch niacin to fenofibrate"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Five days after undergoing right knee arthroplasty for osteoarthritis, a 68-year-old man has severe pain in this right knee preventing him from participating in physical therapy. On the third postoperative day when the dressing was changed, the surgical wound appeared to be intact, slightly swollen, and had a clear secretion. He has a history of diabetes, hyperlipidemia, and hypertension. Current medications include metformin, enalapril, and simvastatin. His temperature is 37.3°C (99.1°F), pulse is 94/min, and blood pressure is 130/88 mm Hg. His right knee is swollen, erythematous, and tender to palpation. There is pain on movement of the joint. The medial parapatellar skin incision appears superficially opened in its proximal and distal part with yellow-green discharge. There is blackening of the skin on both sides of the incision. Which of the following is the next best step in the management of this patient?", "answer": "Surgical debridement", "options": {"A": "Surgical debridement", "B": "Nafcillin therapy", "C": "Removal of prostheses", "D": "Vacuum dressing", "E": "Antiseptic dressing\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 53-year-old woman comes to the physician in February because of a 1-day history of fever, chills, headache, and dry cough. She also reports malaise and generalized muscle aches. She works as a teacher at a local high school, where there was recently an outbreak of influenza. She has a history of intermittent asthma, for which she takes albuterol as needed. She declined the influenza vaccine offered in the fall because her sister told her that a friend developed a flulike illness after receiving the vaccine. She is worried about possibly becoming ill and cannot afford to miss work. Her temperature is 37.9°C (100.3°F), heart rate is 58/min, and her respirations are 12/min. Physical examination is unremarkable. Her hemoglobin concentration is 14.5 g/dL, leukocyte count is 9,400/mm3, and platelet count is 280,000/mm3. In addition to analgesia, which of the following is the most appropriate next step in management?", "answer": "Oseltamivir", "options": {"A": "Supportive therapy only", "B": "Amantadine", "C": "Inactivated influenza vaccine", "D": "Oseltamivir", "E": "Live attenuated influenza vaccine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Red-green color blindness, an X-linked recessive disorder, has an incidence of 1/200 in males in a certain population. What is the probability of a phenotypically normal male and female having a child with red-green color blindness?", "answer": "1/400", "options": {"A": "1/200", "B": "199/200", "C": "1/100", "D": "1/400", "E": "99/100"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man is transferred to the intensive care unit from the emergency department for acute respiratory failure. He was rushed to the hospital after developing progressive respiratory distress over the last 24 hours. His medical history is significant for long-standing severe persistent asthma, hypertension, and several bouts of community and hospital-acquired pneumonia. His medications include amlodipine, lisinopril, inhaled fluticasone, salmeterol, and oral prednisone. He is a lifelong non-smoker and drinks alcohol occasionally on the weekends. He works as a sales executive and went to Hawaii a month ago. In the emergency department, he was started on broad-spectrum antibiotics and bronchodilators. His respiratory failure progressively worsens, and on day 2 of admission, he requires mechanical ventilator support. Chest X-ray shows multiple nodules bilaterally in the lower lobes. Flexible bronchoscopy is performed and the bronchoalveolar lavage sample from the medial segment of the right lower lobe shows neutrophils, and the fungal preparation shows Aspergillus fumigatus. A video-assisted thoracoscopy is performed and biopsy from the right lower lobe is taken which shows plugging of the terminal bronchioles with mucus, inflammatory cells, and fungal vascular invasion. Which of the following is the most likely mechanism responsible for the biopsy findings?", "answer": "Defects in the immune response", "options": {"A": "Defects in the immune response", "B": "The production of a superantigen by Aspergillus fumigatus", "C": "Aspergillus fumigatus suppresses the production of IgA", "D": "Aspergillus fumigatus suppresses the production of IgM", "E": "Suppression of the innate immune system by Aspergillus fumigatus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 70-year-old man comes to the physician because of a 4-month history of epigastric pain, nausea, and weakness. He has smoked one pack of cigarettes daily for 50 years and drinks one alcoholic beverage daily. He appears emaciated. He is 175 cm (5 ft 9 in) tall and weighs 47 kg (103 lb); BMI is 15 kg/m2. He is diagnosed with gastric cancer. Which of the following cytokines is the most likely direct cause of this patient’s examination findings?", "answer": "IL-6", "options": {"A": "TGF-β", "B": "IL-6", "C": "IL-2", "D": "IFN-α", "E": "TNF-β"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old woman comes to the physician because of a 1-week history of fatigue, dark urine, and a feeling of heaviness in her legs. Two weeks ago, she returned from a vacation to Brazil, where she spent most of her days exploring the city of Rio de Janeiro on foot. She also gained 3 kg (7 lb) during her vacation. She has systemic lupus erythematosus. Her only medication is hydroxychloroquine. Her temperature is 37.5°C (99.5°F), pulse is 78/min, and blood pressure is 162/98 mm Hg. Physical examination shows 2+ pretibial edema bilaterally. Urinalysis shows:\nBlood 3+\nProtein 1+\nRBC 6–8/hpf with dysmorphic features\nRBC casts numerous\nWBC 8/hpf\nWBC casts rare\nBacteria negative\nWhich of the following is the most likely cause of this patient's leg findings?\"", "answer": "Salt retention", "options": {"A": "Venous insufficiency", "B": "Lymphatic obstruction", "C": "Increased capillary permeability", "D": "Renal protein loss", "E": "Salt retention"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 67-year-old woman with advanced bladder cancer comes to the physician for a follow-up examination. She is currently undergoing chemotherapy with an agent that forms cross-links between DNA strands. Serum studies show a creatinine concentration of 2.1 mg/dL and a blood urea nitrogen concentration of 30 mg/dL. Urine dipstick of a clean-catch midstream specimen shows 2+ protein and 1+ glucose. Prior to initiation of chemotherapy, her laboratory values were within the reference range. In addition to hydration, administration of which of the following would most likely have prevented this patient's current condition?", "answer": "Amifostine", "options": {"A": "Mesna", "B": "Aprepitant", "C": "Amifostine", "D": "Rasburicase", "E": "Leucovorin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old post-menopausal woman comes to the physician because of intermittent, bloody post-coital vaginal discharge for the past month. She does not have pain with intercourse. Eleven years ago, she had LSIL on a routine Pap smear and testing for high-risk HPV strains was positive. Colposcopy showed CIN 1. She has not returned for follow-up Pap smears since then. She is sexually active with her husband only, and they do not use condoms. She has smoked half a pack of cigarettes per day for the past 25 years and does not drink alcohol. On speculum exam, a 1.4 cm, erythematous exophytic mass with ulceration is noted on the posterior wall of the upper third of the vagina. Which of the following is the most probable histopathology of this mass?", "answer": "Squamous cell carcinoma", "options": {"A": "Squamous cell carcinoma", "B": "Basal cell carcinoma", "C": "Melanoma", "D": "Sarcoma botryoides", "E": "Adenocarcinoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Three days after starting a new drug for malaria prophylaxis, a 19-year-old college student comes to the physician because of dark-colored urine and fatigue. He has not had any fever, dysuria, or abdominal pain. He has no history of serious illness. Physical examination shows scleral icterus. Laboratory studies show a hemoglobin of 9.7 g/dL and serum lactate dehydrogenase of 234 U/L. Peripheral blood smear shows poikilocytes with bite-shaped irregularities. Which of the following drugs has the patient most likely been taking?", "answer": "Primaquine", "options": {"A": "Pyrimethamine", "B": "Primaquine", "C": "Dapsone", "D": "Ivermectin", "E": "Doxycycline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "You are reviewing raw data from a research study performed at your medical center examining the effectiveness of a novel AIDS screening examination. The study enrolled 250 patients with confirmed AIDS, and 240 of these patients demonstrated a positive screening examination. The control arm of the study enrolled 250 patients who do not have AIDS, and only 5 of these patients tested positive on the novel screening examination. What is the NPV of this novel test?", "answer": "245 / (245 + 10)", "options": {"A": "245 / (245 + 10)", "B": "245 / (245 + 5)", "C": "240 / (240 + 5)", "D": "240 / (240 + 15)", "E": "240 / (240 + 10)"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A P1G0 diabetic woman is at risk of delivering at 30 weeks gestation. Her obstetrician counsels her that there is a risk the baby could have significant pulmonary distress after it is born. However, she states she will administer a drug to the mother to help prevent this from occurring. By what action will this drug prevent respiratory distress in the premature infant?", "answer": "Increasing the secretory product of type II alveolar cells", "options": {"A": "Suppressing the neonatal immune system", "B": "Increasing the secretory product of type II alveolar cells", "C": "Preventing infection of immature lungs", "D": "Reducing the secretory product of type II alveolar cells", "E": "Promoting increased surface tension of alveoli"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A case-control study is conducted to investigate the association between the use of phenytoin during pregnancy in women with epilepsy and the risk for congenital malformations. The odds ratio of congenital malformations in newborns born to women who were undergoing treatment with phenytoin is 1.74 (P = 0.02) compared to newborns of women who were not treated with phenytoin. Which of the following 95% confidence intervals is most likely reported for this association?", "answer": "1.34 to 2.36", "options": {"A": "1.75 to 2.48", "B": "0.56 to 1.88", "C": "0.36 to 0.94", "D": "1.34 to 2.36", "E": "0.83 to 2.19"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old boy presents with altered mental status and difficulty breathing for the past couple of hours. The patient’s father, a mechanic, says the boy accidentally ingested an unknown amount of radiator fluid. The patient’s vital signs are: temperature 37.1°C (98.8.F), pulse 116/min, blood pressure 98/78 mm Hg, and respiratory rate 42/min. On physical examination, cardiopulmonary auscultation reveals deep, rapid respirations with no wheezing, rhonchi, or crepitations. An ABG reveals the blood pH to be 7.2 with an anion gap of 16 mEq/L. Urinalysis reveals the presence of oxalate crystals. Which of the following is the most appropriate antidote for the poison that this patient has ingested?", "answer": "Fomepizole", "options": {"A": "Flumazenil", "B": "Succimer", "C": "Methylene blue", "D": "Fomepizole", "E": "Dimercaprol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man with HIV comes to the physician because of multiple lesions on his chest and lower extremities. The lesions have progressively increased in size and are not painful or pruritic. Current medications include abacavir, dolutegravir, and lamivudine. A photograph of the lesions is shown. His CD4+ T-lymphocyte count is 450/mm3 (normal ≥ 500/mm3). A skin biopsy shows multiple spindle-shaped cells and lymphocytic infiltrate. Which of the following is the most appropriate pharmacotherapy?", "answer": "Alpha-interferon", "options": {"A": "Ganciclovir", "B": "Nitazoxanide", "C": "Alpha-interferon", "D": "Amphotericin B", "E": "Doxycycline"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 18-year-old man presents to the office, complaining of an itchy patch on his torso that appeared one week ago. The patient is on the college wrestling team and is concerned he will not be able to compete if it gets infected. He has no significant medical history, and his vital signs are within normal limits. On examination, there is an erythematous, scaly plaque with central clearing at approximately the level of rib 6 on the left side of his torso. What diagnostic test would be most appropriate at this time?", "answer": "KOH preparation", "options": {"A": "Sabouraud agar", "B": "Eaton agar", "C": "Thayer-Martin agar", "D": "KOH preparation", "E": "Wood’s lamp examination"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old man with no significant medical history begins to have memory loss and personality changes. Rapidly, over the next few months his symptoms increase in severity. He experiences a rapid mental deterioration associated with sudden, jerking movements, particularly in response to being startled. He has gait disturbances as well. Eventually, he lapses into a coma and dies approximately ten months after the onset of symptoms. Which of the following would most likely be seen on autopsy of the brain in this patient?", "answer": "C", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old woman with type 1 diabetes mellitus is brought to the emergency department by her husband because of a 2-day history of profound fatigue and generalized weakness. One week ago, she increased her basal insulin dose because of inadequate control of her glucose concentrations. Neurologic examination shows hyporeflexia. An ECG shows T-wave flattening and diffuse ST-segment depression. Which of the following changes are most likely to occur in this patient's kidneys?", "answer": "Increased activity of H+/K+ antiporter in α-intercalated cells", "options": {"A": "Increased activity of H+/K+ antiporter in α-intercalated cells", "B": "Decreased activity of epithelial Na+ channels in principal cells", "C": "Decreased activity of Na+/K+/2Cl- cotransporter in the loop of Henle", "D": "Decreased activity of Na+/H+ antiporter in the proximal convoluted tubule", "E": "Increased activity of luminal K+ channels in principal cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A newborn male is evaluated in the hospital nursery 24 hours after birth for cyanosis. The patient was born at 38 weeks gestation to a 36-year-old gravida 3 via cesarean section for fetal distress. The patient’s mother received inconsistent prenatal care, and the delivery was uncomplicated. The patient’s Apgar evaluation was notable for acrocyanosis at both 1 and 5 minutes of life. The patient’s mother denies any family history of congenital heart disease. The patient’s father has a past medical history of hypertension, and one of the patient’s older siblings was recently diagnosed with autism spectrum disorder. The patient’s birth weight was 3180 g (7 lb 0 oz). In the hospital nursery, his temperature is 99.3°F (37.4°C), blood pressure is 66/37 mmHg, pulse is 179/min, and respirations are 42/min. On physical exam, the patient is in moderate distress. He has low-set ears, orbital hypertelorism, and a cleft palate. The patient is centrally cyanotic. A chest CT shows thymic hypoplasia. Echocardiography demonstrates a single vessel emanating from both the right and left ventricle.\n\nThis patient should be urgently evaluated for which of the following acute complications?", "answer": "Neuromuscular irritability", "options": {"A": "Cerebral edema", "B": "Hypoglycemia", "C": "Neuromuscular irritability", "D": "Rhabdomyolysis", "E": "Shortening of the QT interval"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 29-year-old woman comes to the physician because of intermittent episodes of sharp chest pain and palpitations. She appears nervous. Her pulse is 115/min and irregularly irregular, and blood pressure is 139/86 mmHg. Examination shows a fine tremor on both hands and digital swelling; the extremities are warm. There is retraction of the right upper eyelid. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Propranolol", "options": {"A": "Amiodarone", "B": "Propylthiouracil", "C": "Warfarin", "D": "Methimazole", "E": "Propranolol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old female is found by her roommate in her dormitory. The patient has a history of Type 1 Diabetes Mellitus and was binge drinking the night prior with friends at a local bar. The patient is brought to the emergency department, where vital signs are as follow: T 97.3 F, HR 119 bpm, BP 110/68 mmHg, RR 24, SpO2 100% on RA. On physical exam, the patient is clammy to touch, mucous membranes are tacky, and she is generally drowsy and disoriented. Finger stick glucose is 342 mg/dL; additional lab work reveals: Na: 146 K: 5.6 Cl: 99 HCO3: 12 BUN: 18 Cr: 0.74. Arterial Blood Gas reveals: pH 7.26, PCO2 21, PO2 102. Which of the following statements is correct regarding this patient's electrolyte and acid/base status?", "answer": "The patient has an anion gap metabolic acidosis with decreased total body potassium", "options": {"A": "The patient has a primary respiratory alkalosis with a compensatory metabolic acidosis", "B": "The patient has a metabolic acidosis with hyperkalemia from increased total body potassium", "C": "The patient has an anion gap metabolic acidosis as well as a respiratory acidosis", "D": "The patient has an anion gap metabolic acidosis with decreased total body potassium", "E": "The patient has a non-anion gap metabolic acidosis with decreased total body sodium"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old man is admitted to the hospital because of a 1-day history of epigastric pain and vomiting. He has had similar episodes of epigastric pain in the past. He drinks 8 oz of vodka daily. Five days after admission, the patient develops aspiration pneumonia and sepsis. Despite appropriate therapy, the patient dies. At autopsy, the pancreas appears gray, enlarged, and nodular. Microscopic examination of the pancreas shows localized deposits of calcium. This finding is most similar to an adaptive change that can occur in which of the following conditions?", "answer": "Congenital CMV infection", "options": {"A": "Primary hyperparathyroidism", "B": "Chronic kidney disease", "C": "Sarcoidosis", "D": "Congenital CMV infection", "E": "Multiple myeloma\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old patient is being evaluated for involuntary movements, difficulty swallowing food, and personality change. He has entered a clinical trial that is studying the interaction of certain neuromediators in patients with similar (CAG) n trinucleotide repeat disorders. The laboratory results of 1  of the candidates for the clinical trial are presented below:\nAcetylcholine ↓\nDopamine ↑\nGamma-aminobutyric acid (GABA) ↓\nNorepinephrine unchanged\nSerotonin unchanged\nWhich trinucleotide disorder most likely represents the diagnosis of this patient?", "answer": "Huntington's disease", "options": {"A": "Myotonic dystrophy", "B": "Friedreich's ataxia", "C": "Fragile X syndrome", "D": "Huntington's disease", "E": "Spinobulbar muscular atrophy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old man with hypertension comes to the physician for a routine health maintenance examination. Current medications include atenolol, lisinopril, and atorvastatin. His pulse is 86/min, respirations are 18/min, and blood pressure is 145/95 mm Hg. Cardiac examination is shown. Which of the following is the most likely cause of this physical examination finding?", "answer": "Decreased compliance of the left ventricle", "options": {"A": "Decreased compliance of the left ventricle", "B": "Myxomatous degeneration of the mitral valve", "C": "Inflammation of the pericardium", "D": "Dilation of the aortic root", "E": "Thickening of the mitral valve leaflets"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man presents to the hospital with chief complaints of unintentional weight loss, anorexia, fever, and sweating. The patient has pleuritic chest pain, progressive dyspnea, and dry cough. There is no history of orthopnea or paroxysmal nocturnal dyspnea. On examination, the patient is afebrile and pericardial friction rub is noted. ECG shows diffuse ST-segment elevation in V1-V4 along with T wave inversion. Chest X-ray and CT scan show anterior and inferior pericardial eggshell calcification. Echocardiography reveals thickened pericardium and signs of diastolic right ventricular collapse. Pericardial fluid is sent for Ziehl-Neelsen staining to detect acid-fast bacilli. Mycobacterium tuberculosis is detected by PCR. What is the most likely mechanism associated with the patient’s condition?", "answer": "Dystrophic calcification", "options": {"A": "Metastatic calcifications", "B": "Dystrophic calcification", "C": "Primary amyloidosis", "D": "Secondary amyloidosis", "E": "Age-related amyloidosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-month-old infant with Tetralogy of Fallot is brought to the emergency department by her parents because of a 1-day history of fever, cough, and difficulty breathing. She was born at 29 weeks of gestation. Her routine immunizations are up-to-date. She is currently in the 4th percentile for length and 2nd percentile for weight. She appears ill. Her temperature is 39.1°C (102.3°F). Physical examination shows diffuse wheezing, subcostal retractions, and bluish discoloration of the fingertips. Administration of which of the following would most likely have prevented this patient's current condition?", "answer": "Palivizumab", "options": {"A": "Ribavirin", "B": "Oseltamivir", "C": "Ganciclovir", "D": "Ceftriaxone", "E": "Palivizumab"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old woman has been receiving amoxicillin for acute sinusitis for 12 days. She develops a macular rash on her neck, back, and torso. The amoxicillin is therefore changed to cephalexin for an additional week. The rash resolves, but she returns complaining of fatigue, flank pain, and fever that has persisted despite the resolution of the sinusitis. She has a history of essential hypertension, hyperlipidemia, and gastric reflux. She has been on a stable regimen of lisinopril, simvastatin, and omeprazole. Today, her vital signs reveal: temperature 37.9°C (100.2°F), blood pressure 145/90 mm Hg, regular pulse 75/min, and respirations 16/min. The physical examination is unremarkable. Serum urea and creatinine are elevated. Urinalysis shows leukocyturia, but urine bacterial culture is negative. A urine cytospin stained with Hansel’s solution reveals 3% binucleated cells with eosinophilic, granular cytoplasm. Which of the following is the most likely diagnosis?", "answer": "Acute interstitial nephritis", "options": {"A": "Acute interstitial nephritis", "B": "Acute glomerulonephritis", "C": "Acute tubular necrosis", "D": "Acute vascular injury", "E": "IgA nephropathy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 61-year-old man with a history of stage IIIa lung adenocarcinoma that has been treated with wedge resection and chemotherapy presents to the primary care clinic. He is largely asymptomatic, but he demonstrates a persistent microcytic anemia despite iron supplementation. Colonoscopy performed 3 years earlier was unremarkable. His past medical history is significant for diabetes mellitus type II, hypertension, acute lymphoblastic leukemia as a child, and hypercholesterolemia. He currently smokes 1 pack of cigarettes per day, drinks a glass of pinot grigio per day, and currently denies any illicit drug use. His vital signs include: temperature, 36.7°C (98.0°F); blood pressure, 126/74 mm Hg; heart rate, 87/min; and respiratory rate, 17/min. On physical examination, his pulses are bounding, complexion is pale, but breath sounds remain clear. Oxygen saturation was initially 91% on room air, with a new oxygen requirement of 2 L by nasal cannula. Which of the following lab values would suggest anemia of chronic disease as the underlying etiology?", "answer": "Decreased serum iron and transferrin, increased ferritin, normal serum transferrin receptor", "options": {"A": "Decreased serum iron and transferrin, increased ferritin, normal serum transferrin receptor", "B": "Decreased serum iron, increased transferrin, decreased ferritin, increased serum transferrin receptor", "C": "Increased serum iron and transferrin, increased ferritin, normal serum transferrin receptor", "D": "Decreased serum iron and transferrin, decreased ferritin, normal serum transferrin receptor", "E": "Increased serum iron and transferrin, decreased ferritin, normal serum transferrin receptor"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old woman presents to her physician with a painless breast mass on her left breast for the past 4 months. She mentions that she noticed the swelling suddenly one day and thought it would resolve by itself. Instead, it has been slowly increasing in size. On physical examination of the breasts, the physician notes a single non-tender, hard, and fixed nodule over left breast. An ultrasonogram of the breast shows a solid mass, and a fine-needle aspiration biopsy confirms the mass to be lobular carcinoma of the breast. When the patient asks about her prognosis, the physician says that the prognosis can be best determined after both grading and staging of the tumor. Based on the current diagnostic information, the physician says that they can only grade, but no stage, the neoplasm. Which of the following facts about the neoplasm is currently available to the physician?", "answer": "The tumor cells exhibit marked nuclear atypia.", "options": {"A": "The tumor cells exhibit marked nuclear atypia.", "B": "The tumor invades the pectoralis major.", "C": "The tumor has metastasized to the axillary lymph nodes.", "D": "The tumor has not metastasized to the contralateral superior mediastinal lymph nodes.", "E": "The tumor has spread via blood-borne metastasis."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old woman has fallen from the second story level of her home while hanging laundry. She was brought to the emergency department immediately and presented with severe abdominal pain. The patient is anxious, and her hands and feet feel very cold to the touch. There is no evidence of bone fractures, superficial skin wounds, or a foreign body penetration. Her blood pressure is 102/67 mm Hg, respirations are 19/min, pulse is 87/min, and temperature is 36.7°C (98.0°F). Her abdominal exam reveals rigidity and severe tenderness. A Foley catheter and nasogastric tube are inserted. The central venous pressure (CVP) is 5 cm H2O. The medical history is significant for hypertension. Which of the following is best indicated for the evaluation of this patient?", "answer": "Ultrasound", "options": {"A": "X-Ray", "B": "Ultrasound", "C": "Peritoneal lavage", "D": "CT scan", "E": "Diagnostic laparotomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 74-year-old female is brought to the emergency department because of a 2-week history of increasing weakness and chills. She also notes difficulty breathing for the last three days. Eight weeks ago, she underwent left hemicolectomy for adenocarcinoma of the colon. She subsequently developed a severe urinary tract infection, was treated in the intensive care unit for four days, and was discharged from the hospital three weeks ago. She has type 2 diabetes mellitus, osteoporosis with lumbar pain, hypertension, and atrial fibrillation. She has smoked one pack of cigarettes daily for 50 years. She does not drink alcohol and has never used illicit drugs. Current medications include warfarin, metformin, lisinopril, and aspirin. She appears lethargic and has a large conjunctival hemorrhage in her left eye. Her temperature is 39.3°C (102.7°F), pulse is 112/min, respirations are 25/min, and blood pressure is 126/79 mm Hg. Cardiac auscultation reveals a new holosystolic murmur over the apex. Abdominal examination shows mild, diffuse tenderness throughout the upper quadrants and a well-healed 12-cm paramedian scar. There are multiple tender nodules on the palmar surface of her fingertips. Funduscopic examination shows retinal hemorrhages with pale centers. An ECG shows atrial fibrillation and right bundle branch block. Which of the following is the most likely underlying etiology of this patient's condition?", "answer": "Enterococcus faecalis infection", "options": {"A": "Pulmonary metastases", "B": "Streptococcus sanguinis infection", "C": "Cardiobacterium hominis infection", "D": "Aspergillus fumigatus infection", "E": "Enterococcus faecalis infection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old woman presents to her physician with a persistent cough. She has been unable to control her cough and also is finding it increasingly difficult to breathe. The cough has been persistent for about 2 months now, but 2 weeks ago she started noticing streaks of blood in the sputum regularly after coughing. Over the course of 4 months, she has also observed an unusual loss of 10 kg (22 lb) in her weight. She has an unchanged appetite and remains fairly active, which makes her suspicious as to the cause of her weight loss. Another troublesome concern for her is that on a couple occasions over the past few weeks, she has observed herself drenched in sweat when she wakes up in the morning. Other than having a 35 pack-year smoking history, her medical history is insignificant. She is sent for a chest X-ray which shows a central nodule of about 13 mm located in the hilar region. Which of the following would be the next best step in the management of this patient?", "answer": "Mediastinoscopy", "options": {"A": "Chemotherapy", "B": "Mediastinoscopy", "C": "Radiotherapy", "D": "Surgical removal", "E": "Repeat surveillance after 6 months"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the emergency department by his parents after they found him to be lethargic and febrile. His current symptoms started 1 week ago and initially consisted of a sore throat and a runny nose. He subsequently developed a fever and productive cough that has become worse over time. Notably, this patient has previously presented with pneumonia and gastroenteritis 8 times since he was born. On presentation, the patient's temperature is 103°F (39.4°C), blood pressure is 90/50 mmHg, pulse is 152/min, and respirations are 38/min. Based on clinical suspicion, an antibody panel is obtained and the results show low levels of IgG and IgA relative to the level of IgM. The expression of which of the following genes is most likely abnormal in this patient?", "answer": "CD40L", "options": {"A": "CD40L", "B": "STAT3", "C": "LYST", "D": "CD18", "E": "NADPH oxidase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 71-year-old man comes to the emergency department because of a 2-month history of severe muscle cramps and back pain. He says that he is homeless and has not visited a physician in the past 20 years. He is 183 cm (6 ft 0 in) tall and weighs 62 kg (137 lb); BMI is 18.5 kg/m2. His blood pressure is 154/88 mm Hg. Physical examination shows pallor, multiple cutaneous excoriations, and decreased sensation over the lower extremities. Serum studies show:\nCalcium 7.2 mg/dL\nPhosphorus 5.1 mg/dL\nGlucose 221 mg/dL\nCreatinine 4.5 mg/dL\nAn x-ray of the spine shows alternating sclerotic and radiolucent bands in the lumbar and thoracic vertebral bodies. Which of the following is the most likely explanation for these findings?\"", "answer": "Secondary hyperparathyroidism", "options": {"A": "Tertiary hyperparathyroidism", "B": "Secondary hyperparathyroidism", "C": "Primary hypoparathyroidism", "D": "Pseudohypoparathyroidism", "E": "Multiple myeloma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman presents to her primary care physician for knee pain. The patient states it started yesterday and has been steadily worsening. She recently joined a volleyball team to try to get into shape as she was informed that weight loss would be beneficial for her at her last physical exam. She states that she has been repetitively pivoting and twisting on her knee while playing volleyball. The patient has a past medical history of polycystic ovarian syndrome and is currently taking oral contraceptive pills. Her temperature is 98.5°F (36.9°C), blood pressure is 137/88 mmHg, pulse is 90/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam reveals an obese woman with facial hair. Physical exam is notable for tenderness that is mediated with palpation over the medial aspect of the tibia just inferior to the patella. Her BMI is 37 kg/m^2. The rest of the exam of the lower extremity is not remarkable. Which of the following is the most likely diagnosis?", "answer": "Pes anserine bursitis", "options": {"A": "Medial collateral ligament tear", "B": "Medial meniscus tear", "C": "Osteoarthritis", "D": "Patellofemoral syndrome", "E": "Pes anserine bursitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 47-year-old woman comes to the physician because of a 6-week history of fatigue and low-grade fever. She has no history of serious illness except for a bicuspid aortic valve, diagnosed 10 years ago. She does not use illicit drugs. Her temperature is 37.7°C (99.9°F). Physical examination shows petechiae under the fingernails and multiple tender, red nodules on the fingers. A new grade 2/6 diastolic murmur is heard at the right second intercostal space. Which of the following is the most likely causal organism?", "answer": "Streptococcus sanguinis", "options": {"A": "Enterococcus faecalis", "B": "Staphylococcus epidermidis", "C": "Streptococcus pyogenes", "D": "Streptococcus sanguinis", "E": "Streptococcus pneumoniae"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old man is rushed to the emergency department after a motor vehicle accident. The patient states that he feels weakness and numbness in both of his legs. He also reports pain in his lower back. His airway, breathing, and circulation is intact, and he is conversational. Neurologic exam is significant for bilateral lower extremity flaccid paralysis and impaired pain and temperature sensation up to T10-T11 with normal vibration sense. A computerized tomography scan of the spine is performed which shows a vertebral burst fracture of the vertebral body at the level of T11. Which of the following findings is most likely present in this patient?", "answer": "Preserved fine touch", "options": {"A": "Impaired proprioception sense", "B": "Preserved fine touch", "C": "Preserved crude touch", "D": "Hyperreflexia at the level of the lesion", "E": "Normal bladder function"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old obese woman presents with painless postmenopausal bleeding for the past 5 days. A recent endometrial biopsy confirmed endometrial cancer, and the patient is scheduled for total abdominal hysterectomy and bilateral salpingo-oophorectomy. Past medical history is significant for stress incontinence and diabetes mellitus type 2. Menarche was at age 11 and menopause was at age 55. The patient has 4 healthy children from uncomplicated pregnancies, who were all formula fed. Current medications are topical estrogen and metformin. Family history is significant for breast cancer in her grandmother at age 80. Which of the following aspects of this patient’s history is associated with a decreased risk of breast cancer?", "answer": "Multiple pregnancies", "options": {"A": "Early menarche", "B": "Obesity", "C": "Formula feeding", "D": "Endometrial cancer", "E": "Multiple pregnancies"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A middle-aged homeless man is found lying unresponsive on the streets by the police and is rushed to the emergency department. His vital signs include: blood pressure 110/80 mm Hg, pulse rate 100/min, and respirations 10/min and shallow. On physical examination, his extremities are cold and clammy. Pupils are constricted and non-reactive. His blood glucose is 55 mg/dL. IV access is established immediately with the administration of dextrose and naloxone. In half an hour, the patient is fully conscious, alert and responsive. He denies any medical illnesses, hospitalizations, or surgeries in the past. Physical examination reveals injection track marks along both arms. He admits to the use of cocaine and heroin. He smokes cigarettes and consumes alcohol. His vital signs are now stable. A urine sample is sent for toxicology screening. Which of the following was the most likely cause of this patient’s respiratory depression?", "answer": "Opioid intoxication", "options": {"A": "Hallucinogen toxicity", "B": "Cocaine abuse", "C": "Hypoglycemia", "D": "Alcohol intoxication", "E": "Opioid intoxication"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old female with a history of hypertension presents to your outpatient clinic for numbness, tingling in her right hand that has been slowly worsening over the last several months. She has tried using a splint but receives minimal relief. She is an analyst for a large consulting firm and spends most of her workday in front of a computer. Upon examination, you noticed that the patient has a prominent jaw and her hands appear disproportionately large. Her temperature is 99 deg F (37.2 deg C), blood pressure is 154/72 mmHg, pulse is 87/min, respirations are 12/min. A fasting basic metabolic panel shows: Na: 138 mEq/L, K: 4.1 mEq/L, Cl: 103 mEq/L, CO2: 24 mEq/L, BUN: 12 mg/dL, Cr: 0.8 mg/dL, Glucose: 163 mg/dL. Which of the following tests would be most helpful in identifying the underlying diagnosis?", "answer": "Measurement of insulin-like growth factor 1 alone and growth hormone levels after oral glucose", "options": {"A": "Measurement of serum morning cortisol levels and dexamethasone suppression test", "B": "Measurement of insulin-like growth factor 1 alone and growth hormone levels after oral glucose", "C": "Measurement of thyroid stimulating hormone", "D": "Measurement of serum growth hormone alone", "E": "Measurement of insulin-like growth factor 1 levels alone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 17-year-old woman is rushed into the emergency department by her father who found her collapsed in her bedroom 15 minutes before the ambulance's arrival. There was an empty bottle of clomipramine in her bedroom which her mother takes for her depression. Vital signs include the following: respiratory rate 8/min, pulse 130/min, and blood pressure 100/60 mm Hg. On physical examination, the patient is unresponsive to vocal and tactile stimuli. Oral mucosa and tongue are dry, and the bladder is palpable. A bedside electrocardiogram (ECG) shows widening of the QRS complexes. Which of the following would be the best course of treatment in this patient?", "answer": "Sodium bicarbonate", "options": {"A": "Sodium bicarbonate", "B": "Lidocaine", "C": "Induced vomiting", "D": "Norepinephrine", "E": "Diazepam"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-year-old girl is brought to the physician by her 30-year-old mother, who reports that her daughter has been passing multiple foul-smelling, bulky stools with flatulence every day for the last 6 months. The girl was born in Guatemala, and soon after her birth, her parents moved to the United States so that they could access better healthcare. During pregnancy, the mother had little prenatal care, but labor and delivery were uneventful. However, the newborn had significant abdominal distention immediately at birth that increased when she ate or yawned. She failed to pass stool in the first 24 hours of life and had greenish-black vomitus. The parents report similar symptoms in other family members. After diagnosis, the girl underwent a procedure that alleviated her symptoms; however, there was no remission. Her abdominal X-ray (see the first image) and barium contrast enema (second image) from when she was born is shown. Her blood pressure is 100/68 mm Hg, heart rate is 96/min, respiratory rate is 19/min, and temperature is 36.7°C (98.0°F). The girl is in the 10th percentile for height and weight. On physical exam, she has periumbilical and midepigastric tenderness to palpation without rebound tenderness or guarding. There is a slight genu varum deformity and bony tenderness noted in her legs. She has foul-smelling flatulation 2–3 times during the visit. Her rectosphincteric reflex is intact. She has decreased fecal elastase and a negative D-xylose test. Which of the following is the most appropriate long-term treatment for her condition?", "answer": "Enzyme-replacement therapy", "options": {"A": "Enzyme-replacement therapy", "B": "Broad-spectrum antibiotics", "C": "Rectal suction biopsy and surgical correction (Hirschsprung)", "D": "Duodenal atresia repair", "E": "Cholecalciferol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old, multiparous, woman comes to the physician because of urinary leakage for the past 4 months. She involuntarily loses a small amount of urine after experiencing a sudden, painful sensation in the bladder. She wakes up at night several times to urinate, and she sometimes cannot make it to the bathroom in time. She has diabetes mellitus type 2 controlled with insulin and a history of pelvic organ prolapse, for which she underwent surgical treatment 5 years ago. Menopause was 11 years ago. She drinks 4-5 cups of coffee daily. Pelvic examination shows no abnormalities, and a Q-tip test is negative. Ultrasound of the bladder shows a normal postvoid residual urine. Which of the following is the underlying cause of this patient's urinary incontinence?", "answer": "Increased detrusor muscle activity", "options": {"A": "Recurrent pelvic organ prolapse", "B": "Decreased pelvic floor muscle tone", "C": "Increased detrusor muscle activity", "D": "Increased urine bladder volumes", "E": "Decreased estrogen levels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old woman with type 1 diabetes mellitus comes to the emergency department for evaluation of a 1-month history of fever, fatigue, loss of appetite, and a 3.6-kg (8-lb) weight loss. She has also had a cough for the last 2 months. She reports recent loss of pubic hair. The patient immigrated from the Philippines 7 weeks ago. Her mother has systemic lupus erythematosus. She has never smoked and does not drink alcohol. Her only medication is insulin, but she sometimes misses doses. She is 165 cm (5 ft 5 in) tall and weighs 49 kg (108 lb); BMI is 18 kg/m2. She appears lethargic. Her temperature is 38.9°C (102°F), pulse is 58/min, and blood pressure is 90/60 mm Hg. Examination shows decreased sensation to touch and vibration over both feet. The remainder of the examination shows no abnormalities. Serum studies show:\nNa+ 122 mEq/L\nCl- 100 mEq/L\nK+ 5.8 mEq/L\nGlucose 172 mg/dL\nAlbumin 2.8 g/dL\nCortisol 2.5 μg/dL\nACTH 531.2 pg/mL (N=5–27 pg/mL)\nCT scan of the abdomen with contrast shows bilateral adrenal enlargement. Which of the following is the most likely underlying mechanism of this patient's symptoms?\"", "answer": "Infection with acid-fast bacilli", "options": {"A": "Adrenal infarction", "B": "Adrenal hemorrhage", "C": "Pituitary tumor", "D": "Infection with acid-fast bacilli", "E": "Autoimmune adrenalitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old man is brought to the emergency department following an episode of loss of consciousness 1 hour ago. He had just finished micturating, when he fell down. His wife heard the noise and found him unconscious on the floor. He regained consciousness after 30 seconds and was able to talk normally with his wife immediately. There was no urinary incontinence. On arrival, he is alert and oriented. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. Serum concentrations of glucose, creatinine, and electrolytes are within the reference range. An electrocardiogram shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Situational syncope", "options": {"A": "Cardiovascular syncope", "B": "Situational syncope", "C": "Emotional syncope", "D": "Neurocardiogenic syncope", "E": "Arrhythmogenic syncope"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3000-g (6.6-lb) female newborn is delivered at term to a 23-year-old primigravid woman. The mother has had no prenatal care. Immunization records are not available. Cardiac examination shows a continuous heart murmur. There are several bluish macules on the skin that do not blanch with pressure. Slit lamp examination shows cloudy lenses in both eyes. The newborn does not pass his auditory screening tests. Which of the following is the most likely diagnosis?", "answer": "Congenital rubella infection", "options": {"A": "Congenital parvovirus infection", "B": "Congenital toxoplasmosis", "C": "Congenital rubella infection", "D": "Congenital cytomegalovirus infection", "E": "Congenital syphilis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A group of investigators conducted a randomized controlled trial to compare the effectiveness of rivaroxaban to warfarin for ischemic stroke prevention in patients with atrial fibrillation. A total of 14,000 participants were enrolled and one half was assigned to each of the cohorts. The patients were followed prospectively for 3 years. At the conclusion of the trial, the incidence of ischemic stroke in participants taking rivaroxaban was 1.7% compared to 2.2% in participants taking warfarin. The hazard ratio is calculated as 0.79 and the 95% confidence interval is reported as 0.64 to 0.97. If the study was conducted with a total of 7,000 participants, which of the following changes would most be expected?", "answer": "Increased confidence interval range", "options": {"A": "Increased risk of selection bias", "B": "Decreased hazard ratio", "C": "Increased confidence interval range", "D": "Decreased type I error rate", "E": "Increased risk of confounding bias"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old woman comes to the physician for the evaluation of a left breast mass that she noticed 4 weeks ago. It has rapidly increased in size during this period. Vital signs are within normal limits. Examination shows large dense breasts; a 6-cm, nontender, multinodular mass is palpated in the upper outer quadrant of the left breast. There are no changes in the skin or nipple. There is no palpable cervical or axillary adenopathy. Mammography shows a smooth polylobulated mass. An image of a biopsy specimen is shown. Which of the following is the most likely diagnosis?", "answer": "Phyllodes tumor", "options": {"A": "Comedocarcinoma", "B": "Invasive ductal carcinoma", "C": "Fibroadenoma", "D": "Phyllodes tumor", "E": "Invasive lobular carcinoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is studying obesity in mice. Over the course of 2 weeks, mice in the experimental group receive a daily injection with a synthetic analog of an endogenous hormone. Compared to the control group, the hormone-injected mice eat more and gain significantly more weight. Which of the following is the most likely explanation for the observed weight gain in the experimental group?", "answer": "Ghrelin stimulation of the lateral hypothalamus", "options": {"A": "Cholecystokinin stimulation of the nucleus tractus solitarius", "B": "Somatostatin inhibition of the anterior pituitary", "C": "Leptin stimulation of the ventromedial hypothalamus", "D": "Ghrelin stimulation of the lateral hypothalamus", "E": "Glucagon stimulation of hepatocytes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old man presents to the emergency department because of pain and swelling in his left leg over the past few hours. He traveled from Sydney to Los Angeles 2 days ago. He has had type 2 diabetes mellitus for 10 years and takes metformin for it. He has smoked a pack of cigarettes daily for 25 years. His temperature is 36.9°C (98.4°F), the blood pressure is 140/90 mm Hg, and the pulse is 90/min. On examination, the left calf is 5 cm greater in circumference than the right. The left leg appears more erythematous than the right with dilated superficial veins. Venous duplex ultrasound shows non-compressibility. Which of the following best represents the mechanism of this patient’s illness?", "answer": "Impaired venous blood flow", "options": {"A": "Impaired arterial blood flow", "B": "Impaired venous blood flow", "C": "Impaired lymphatic blood flow", "D": "Subcutaneous soft-tissue infection that may extend to the deep fascia", "E": "Infection of the dermis and subcutaneous tissues"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A man returns home late at night to find his 15-year-old son and 40-year-old wife unconscious in the family room. He immediately summons emergency services. In the field, pulse oximetry shows oxygen saturation at 100% for both patients. 100% yet they both appear cyanotic. Both patients are provided with 2L of oxygen by way of nasal cannula on the way to the hospital. An arterial blood gas is performed on the teenager and reveals pH of 7.35, PaCO2 of 31.8 mm Hg, PaO2 of 150 mm Hg, HCO3- of 20 mEq/L, SaO2 of 80%, and a COHb of 18%. What is the most likely cause of his condition?", "answer": "Carbon monoxide poisoning", "options": {"A": "Anemic hypoxia", "B": "Diffusion-limited hypoxia", "C": "Methemoglobinemia", "D": "Carbon monoxide poisoning", "E": "Ischemic hypoxia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old research assistant is brought to the emergency department for severe chemical burns 30 minutes after accidentally spilling hydrochloric acid on himself. The burns cover both hands and forearms. His temperature is 37°C (98.6°F), pulse is 112/min, respirations are 20/min, and blood pressure is 108/82 mm Hg. Initial stabilization and resuscitation is begun, including respiratory support, fluid resuscitation, and cardiovascular stabilization. The burned skin is irrigated with saline water to remove the chemical agent. Which of the following is the most appropriate method to verify adequate fluid infusion in this patient?", "answer": "Urinary output\n\"", "options": {"A": "Heart rate", "B": "The Parkland formula", "C": "Blood pressure", "D": "Pulmonary capillary wedge pressure", "E": "Urinary output\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old female with congestive heart failure and type 2 diabetes is brought to the emergency room by her husband because of an altered mental status. He states he normally helps her be compliant with her medications, but he had been away for several days. On physical exam, her temperature is 37.2 C, BP 85/55, and HR 130. Serum glucose is 500 mg/dL. Which of the following is the first step in the management of this patient?", "answer": "IV NS", "options": {"A": "IV ½ NS", "B": "IV NS", "C": "IV D5W", "D": "Subcutaneous insulin injection", "E": "IV insulin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old G2P2002 is recovering in the hospital on postpartum day 3 after a low transverse C-section. During morning rounds, she reports a “pus-like” discharge and shaking chills overnight. She also endorses increased uterine cramping compared to the day before, but her postpartum course has otherwise been uneventful with a well-healing incision and normal vaginal bleeding. The patient’s prenatal care was complicated by HIV with a recent viral load of 400 copies/mL, type I diabetes well controlled on insulin, and a history of herpes simplex virus encephalitis in her first child. She did not have any genital lesions during the most recent pregnancy. Four days ago, she presented to the obstetric triage unit after spontaneous rupture of membranes and onset of labor. She made slow cervical change and reached full dilation after 16 hours, but there was limited fetal descent. Cephalopelvic disproportion was felt to be the reason for arrest of descent, so prophylactic ampillicin was administered and C-section was performed. A vaginal hand was required to dislodge the fetus’s head from the pelvis, and a healthy baby boy was delivered. On postpartum day 3, her temperature is 101.5°F (38.6°C), blood pressure is 119/82 mmHg, pulse is 100/min, and respirations are 14/min. Her incision looks clean and dry, there is mild suprapubic tenderness, and a foul yellow discharge tinged with blood is seen on her pad. Which of the following is the most significant risk factor for this patient’s presentation?", "answer": "C-section after onset of labor", "options": {"A": "HIV positive status", "B": "Prolonged rupture of membranes", "C": "C-section after onset of labor", "D": "History of herpes simplex virus in previous pregnancy", "E": "Maternal diabetes"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old man comes to the physician because of fatigue and shortness of breath with moderate exertion for the past 2 months. Over the past 10 days, he has had low-grade fevers and night sweats. He has no history of serious illness except for a bicuspid aortic valve diagnosed 5 years ago. He has smoked one pack of cigarettes daily for 10 years and drinks 3–5 beers on social occasions. He does not use illicit drugs. The patient takes no medications. He appears weak. His temperature is 37.7°C (99.9°F), pulse is 70/min, and blood pressure is 128/64 mm Hg. The lungs are clear to auscultation. A grade 2/6 systolic murmur is heard best at the right sternal border and second intercostal space. There are several hemorrhages underneath his fingernails on both hands and multiple tender, red nodules on his fingers. Which of the following is the most likely causal organism?", "answer": "Streptococcus sanguinis", "options": {"A": "Staphylococcus epidermidis", "B": "Streptococcus sanguinis", "C": "Streptococcus pneumoniae", "D": "Streptococcus pyogenes", "E": "Candida albicans"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old man presents to the emergency department after a motor vehicle collision. He was the front seat and unrestrained driver in a head on collision. His temperature is 99.2°F (37.3°C), blood pressure is 90/65 mmHg, pulse is 152/min, respirations are 16/min, and oxygen saturation is 100% on room air. Physical exam is notable for a young man who opens his eyes spontaneously and is looking around. He answers questions with inappropriate responses but discernible words. He withdraws from pain but does not have purposeful movement. Which of the following is this patient’s Glasgow coma scale?", "answer": "11", "options": {"A": "7", "B": "9", "C": "11", "D": "13", "E": "15"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old Caucasian female presents at the ER with fever and sharp pain in her chest upon coughing and inhalation. Three weeks earlier she presented to her rheumatologist with a butterfly rash, joint pain and fatigue and was given a diagnosis of systemic lupus erythematosus. A friction rub is present upon physical exam. Which of the following do you most suspect in this patient?", "answer": "Pericarditis", "options": {"A": "Pulmonary hypertension", "B": "Interstitial lung disease", "C": "Acute myocardial infarction", "D": "Pericarditis", "E": "Pericardial tamponade"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old man with a history of alcoholism undergoes an upper endoscopy, which reveals a superficial mucosal tear in the distal esophagus. Laboratory results show a metabolic alkalosis. What is the most likely mechanism of the acid/base disturbance in this patient?", "answer": "Vomiting", "options": {"A": "B12 deficiency", "B": "Anemia", "C": "Vomiting", "D": "Hypokalemia", "E": "Hepatic cirrhosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man comes to the physician because of flank pain, rash, and blood-tinged urine for 1 day. Two months ago, he was started on hydrochlorothiazide for hypertension. He takes acetaminophen for back pain. Examination shows a generalized, diffuse maculopapular rash. Serum studies show a creatinine concentration of 3.0 mg/dL. Renal ultrasonography shows no abnormalities. Which of the following findings is most likely to be observed in this patient?", "answer": "Urinary eosinophils", "options": {"A": "Urinary crystals on Brightfield microscopy", "B": "Dermal IgA deposition on skin biopsy", "C": "Crescent-shape extracapillary cell proliferation", "D": "Mesangial IgA deposits on renal biopsy", "E": "Urinary eosinophils"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Nucleic acid amplification testing (NAAT) of first-void urine confirms infection with Chlamydia trachomatis. Treatment with the appropriate pharmacotherapy is started. Which of the following health maintenance recommendations is most appropriate at this time?", "answer": "Avoid sun exposure", "options": {"A": "Avoid sun exposure", "B": "Avoid drinking alcohol", "C": "Avoid sexual activity for the next month", "D": "Take medication with food", "E": "Schedule an ophthalmology consultation\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 14-year-old boy presents as a new patient to your practice. While conducting your physical exam, you observe the findings depicted in Figures A and B. Which of the following additional findings would most likely be found in this patient?", "answer": "Iris hamartomas", "options": {"A": "The presence of ash-leaf spots", "B": "A family history of seizures and mental retardation", "C": "Facial angiofibromas", "D": "Iris hamartomas", "E": "A white tuft of scalp hair since birth"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator who studies virology obtains a biopsy from the ulcer base of an active genital herpes lesion for viral culture. The cultured virions, along with herpes simplex virions of a different phenotype, are cointroduced into a human epithelial cell in vitro. The progeny viruses are found to have phenotypes that are distinct from the parent strains. Sequencing of these progeny viruses shows that most genomes have material from both parent strains. These findings are best explained by which of the following terms?", "answer": "Recombination", "options": {"A": "Complementation", "B": "Recombination", "C": "Phenotypic mixing", "D": "Reassortment", "E": "Transduction"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old man is rushed to the emergency room with constant, severe right lower abdominal pain that started 7 hours ago in the periumbilical region and later shifted to the right lower quadrant with a gradual increase in intensity. The patient’s blood pressure is 110/80 mm Hg, the heart rate is 76/min, the respiratory rate is 17/min, and the temperature is 37.5℃ (99.5℉). The physical examination shows tenderness, muscle guarding, and rebound over the right lower quadrant of the abdomen. Abdominal sonography shows a dilated appendix with a periappendiceal fluid collection. He is diagnosed with acute appendicitis and undergoes a laparoscopic appendectomy. The histopathologic examination of the removed appendix is shown in the image. Which of the following substances is responsible for attracting the marked cells to the inflamed tissue?", "answer": "IL-8", "options": {"A": "IL-7", "B": "IL-8", "C": "CCL-11", "D": "CXCL-9", "E": "IL-10"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old man presents to his primary care physician for a pre-operative evaluation. He is scheduled for cataract surgery in 3 weeks. His past medical history is notable for diabetes, hypertension, and severe osteoarthritis of the right knee. His medications include metformin, hydrochlorothiazide, lisinopril, and aspirin. His surgeon ordered blood work 1 month ago, which showed a hemoglobin of 14.2 g/dL, INR of 1.2, and an hemoglobin A1c of 6.9%. His vital signs at the time of the visit show BP: 130/70 mmHg, Pulse: 80, RR: 12, and T: 37.2 C. He has no current complaints and is eager for his surgery. Which of the following is the most appropriate course of action for this patient at this time?", "answer": "Medically clear the patient for surgery", "options": {"A": "Medically clear the patient for surgery", "B": "Repeat the patient's CBC and coagulation studies", "C": "Perform an EKG", "D": "Schedule the patient for a stress test and ask him to delay surgery for at least 6 months", "E": "Tell the patient he will have to delay his surgery for at least 1 year"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 19-year-old African female refugee has been granted asylum in Stockholm, Sweden and has been living there for the past month. She arrived in Sweden with her 2-month-old infant, whom she exclusively breast feeds. Which of the following deficiencies is the infant most likely to develop?", "answer": "Vitamin D", "options": {"A": "Vitamin A", "B": "Vitamin B1", "C": "Vitamin D", "D": "Vitamin E", "E": "Vitamin C"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-year-old girl is brought to the emergency department by her mother 30 minutes after having had a seizure. When her mother woke her up that morning, the girl's entire body stiffened and she started shaking vigorously for several minutes. Her mother also reports that over the past few months, her daughter has had multiple episodes of being unresponsive for less than a minute, during which her eyelids were fluttering. The girl did not recall these episodes afterwards. Upon arrival, she appears drowsy. Neurologic examination shows no abnormalities. Which of the following is the most appropriate pharmacotherapy to prevent recurrence of this patient's symptoms?", "answer": "Valproate", "options": {"A": "Phenytoin", "B": "Lorazepam", "C": "Ethosuximide", "D": "Topiramate", "E": "Valproate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 48-year-old female complains of tingling sensation in her fingertips as well as the skin around her mouth which woke her up from sleep. She is in the postoperative floor as she just underwent a complete thyroidectomy for papillary thyroid cancer. Her temperature is 37° C (98.6° F), respirations are 15/min, pulse is 67/min, and blood pressure is 122/88 mm Hg. While recording the blood pressure, spasm of the muscles of the hand and forearm is seen. What is the next best step in the management of this patient?", "answer": "Calcium replacement", "options": {"A": "No treatment is necessary, this is expected following surgery", "B": "Propylthiouracil", "C": "Magnesium replacement", "D": "Albumin infusion", "E": "Calcium replacement"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 23-year old man is brought to the emergency department by his brother after trying to jump out of a moving car. He says that the Federal Bureau of Investigation has been following him for the last 7 months. He recently quit his job at a local consulting firm to work on his mission to rid the world from evil. He does not smoke, drink alcoholic beverages, or use illicit drugs. He takes no medications. His temperature is 36.7°C (98.1°F), pulse is 90/min, respirations are 20/min, and blood pressure is 120/86 mm Hg. On mental status examination, his response to the first question lasted 5 minutes without interruption. He switched topics a number of times and his speech was pressured. He spoke excessively about his plan to “bring absolute justice to the world”. He has a labile affect. There is no evidence of suicidal ideation. A toxicology screen is negative. He is admitted to the hospital for his symptoms and starts therapy. One week later, he develops difficulty walking and a tremor that improves with activity. Which of the following is the most likely cause of this patient's latest symptoms?", "answer": "Dopamine antagonist", "options": {"A": "Dopamine antagonist", "B": "Acetylcholine antagonist", "C": "Serotonin–norepinephrine reuptake inhibitor", "D": "Histamine antagonist", "E": "Selective serotonin reuptake inhibitor"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 10-year-old boy is referred to a pediatric neurologist by his pediatrician for lower extremity weakness. The boy is healthy with no past medical history, but his parents began to notice that he was having difficulty at football practice the previous day. Over the course of the past 24 hours, the boy has become increasingly clumsy and has been “tripping over himself.” On further questioning, the boy had a viral illness the previous week and was out of school for 2 days. Today, the patient’s temperature is 99.3°F (37.4°C), blood pressure is 108/72 mmHg, pulse is 88/min, respirations are 12/min. On motor exam, the patient has 5/5 strength in hip flexion, 5/5 strength in knee extension and flexion, 3/5 strength in foot dorsiflexion, and 5/5 strength in foot plantarflexion. The findings are the same bilaterally. On gait exam, the patient exhibits foot drop in both feet. Which of the following areas would the patient most likely have diminished sensation?", "answer": "First dorsal webspace of foot", "options": {"A": "Anteromedial thigh", "B": "First dorsal webspace of foot", "C": "Lateral foot", "D": "Lateral plantar foot", "E": "Medial plantar foot"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman comes to the physician because of a 1-day history of swelling and pain in the left leg. Two days ago, she returned from a business trip on a long-distance flight. She has alcohol use disorder. Physical examination shows a tender, swollen, and warm left calf. Serum studies show an increased homocysteine concentration and a methylmalonic acid concentration within the reference range. Further evaluation of this patient is most likely to show which of the following serum findings?", "answer": "Decreased folate concentration", "options": {"A": "Increased pyridoxine concentration", "B": "Increased fibrinogen concentration", "C": "Decreased cobalamin concentration", "D": "Decreased protein C concentration", "E": "Decreased folate concentration"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old woman comes to the emergency department because of increasing abdominal pain for 2 days. The pain is diffuse and constant, and she describes it as 7 out of 10 in intensity. She has also had numbness in her lower extremities for 12 hours. She has type 1 diabetes mellitus, migraine with aura, and essential tremor. She appears uncomfortable. She is oriented to place and person only. Her temperature is 37°C (98.6°F), pulse is 123/min, and blood pressure is 140/70 mm Hg. Examination shows a distended abdomen with no tenderness to palpation. Bowel sounds are decreased. Muscle strength and sensation is decreased in the lower extremities. There is a tremor of the right upper extremity. Urinalysis shows elevated levels of aminolevulinic acid and porphobilinogen. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Primidone", "options": {"A": "Primidone", "B": "Amitriptyline", "C": "Flunarizine", "D": "Metoclopramide", "E": "Sumatriptan"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "One week after undergoing sigmoidectomy with end colostomy for complicated diverticulitis, a 67-year-old man has upper abdominal pain. During the surgery, he was transfused two units of packed red blood cells. His postoperative course was uncomplicated. Two days ago, he developed fever. He is currently receiving parenteral nutrition through a central venous catheter. He has type 2 diabetes mellitus, hypertension, and hypercholesterolemia. He is oriented to person, but not to place and time. Prior to admission, his medications included metformin, valsartan, aspirin, and atorvastatin. His temperature is 38.9°C (102.0°F), pulse is 120/min, and blood pressure is 100/60 mmHg. Examination shows jaundice of the conjunctivae. Abdominal examination shows tenderness to palpation in the right upper quadrant. There is no rebound tenderness or guarding; bowel sounds are hypoactive. Laboratory studies show:\nLeukocytes 13,500 /mm3\nSegmented neutrophils 75 %\nSerum\nAspartate aminotransferase 140 IU/L\nAlanine aminotransferase 85 IU/L\nAlkaline phosphatase 150 IU/L\nBilirubin\nTotal 2.1 mg/dL\nDirect 1.3 mg/dL\nAmylase 20 IU/L\nWhich of the following is the most likely diagnosis in this patient?\"", "answer": "Acalculous cholecystitis", "options": {"A": "Acalculous cholecystitis", "B": "Small bowel obstruction", "C": "Anastomotic insufficiency", "D": "Acute pancreatitis", "E": "Hemolytic transfusion reaction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 82-year-old comes to the physician for a routine checkup. He feels well. He has a history of hypertension, peripheral vascular disease, carotid stenosis, and mild dementia. His father had Parkinson's disease and died of a stroke at the age of 74 years. He has smoked one-half pack of cigarettes daily for 30 years but quit at the age of 50 years. He drinks alcohol in moderation. Current medications include aspirin and lisinopril. He appears healthy. His temperature is 36.9°C (98.4°F), pulse is 73/min, respirations are 12/min, and blood pressure is 142/92 mmHg. Examination shows decreased pedal pulses bilaterally. Ankle jerk and patellar reflexes are absent bilaterally. Sensation to light touch, pinprick, and proprioception is intact bilaterally. Muscle strength is 5/5 bilaterally. He describes the town he grew up in with detail but only recalls one of three words after 5 minutes. Which of the following is the most appropriate next step in management for these findings?", "answer": "No further workup required", "options": {"A": "No further workup required", "B": "Carbidopa-levodopa", "C": "CT scan of the head", "D": "Prescribe thiamine supplementation", "E": "Lumbar puncture"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old woman with a history of intravenous drug use is brought to the emergency department because of a 1-day history of fatigue, yellow eyes, confusion, and blood in her stools. She appears ill. Her temperature is 38.1°C (100.6°F). Physical examination shows pain in the right upper quadrant, diffuse jaundice with scleral icterus, and bright red blood in the rectal vault. Further evaluation demonstrates virions in her blood, some of which have a partially double-stranded DNA genome while others have a single-stranded RNA genome. They are found to share an identical lipoprotein envelope. This patient is most likely infected with which of the following pathogens?", "answer": "Deltavirus", "options": {"A": "Calicivirus", "B": "Filovirus", "C": "Hepevirus", "D": "Herpesvirus", "E": "Deltavirus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old woman comes to the physician because of a 2-week history of fatigue and excessive thirst. During this period, she has not been able to sleep through the night because of the frequent urge to urinate. She also urinates more than usual during the day. She drinks 4–5 liters of water and 1–2 beers daily. She has autosomal dominant polycystic kidney disease, hypertension treated with lisinopril, and bipolar disorder. Therapy with valproic acid was begun after a manic episode 3 months ago. Vital signs are within normal limits. Irregular flank masses are palpated bilaterally. The remainder of the examination shows no abnormalities. Laboratory studies show:\nSerum\nNa+ 152 mEq/L\nK+ 4.1 mEq/L\nCl− 100 mEq/L\nHCO3− 25 mEq/L\nCreatinine 1.8 mg/dL\nOsmolality 312 mOsmol/kg\nGlucose 98 mg/dL\nUrine osmolality 190 mOsmol/kg\nThe urine osmolality does not change after 3 hours despite no fluid intake or after administration of desmopressin. Which of the following is the most appropriate next step in management?\"", "answer": "Hydrochlorothiazide therapy", "options": {"A": "Further water restriction", "B": "Amiloride therapy", "C": "Begin infusion of 3% saline", "D": "Hydrochlorothiazide therapy", "E": "Desmopressin therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 54-year-old G2P2 presents to her gynecologist's office with complaints of frequent hot flashes, malaise, insomnia, and mild mood swings for 2 weeks. She has also noticed some pain with intercourse and vaginal dryness during this time. She is otherwise healthy besides hyperlipidemia, controlled on atorvastatin. She has no other past medical history, but underwent hysterectomy for postpartum hemorrhage. She is desiring of a medication to control her symptoms. Which of the following is the most appropriate short-term medical therapy in this patient for symptomatic relief?", "answer": "Hormonal replacement therapy with estrogen alone", "options": {"A": "Hormonal replacement therapy with estrogen alone", "B": "Hormonal replacement therapy with combined estrogen/progesterone", "C": "Hormonal replacement therapy with progesterone alone", "D": "Paroxetine", "E": "Gabapentin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old man is brought to the physician by his wife because she is worried about his unusual behavior. Two weeks ago, he was promoted and is now convinced that he will soon take over the firm. He has been working overtime at the office and spends most of his nights at parties. Whenever he comes home, he asks his wife to have sex with him and rarely sleeps more than 3 hours. He has a history of a similar episode and several periods of depression over the past 2 years. He currently takes no medications. He appears impatient, repeatedly jumps up from his seat, and says, “I have more important things to do.” There is no evidence of suicidal ideation. Urine toxicology screening is negative. Long-term treatment with lithium is started. Which of the following parameters should be regularly assessed in this patient while he is undergoing treatment?", "answer": "Serum thyroid-stimulating hormone", "options": {"A": "Serum thyroid-stimulating hormone", "B": "Serum aminotransferases", "C": "Complete blood count with differential", "D": "Serum glucose", "E": "Urine culture"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 58-year-old man presents to the emergency department for evaluation of intermittent chest pain over the past 6 months. His history reveals that he has had moderate exertional dyspnea and 2 episodes of syncope while working at his factory job. These episodes of syncope were witnessed by others and lasted roughly 30 seconds. The patient states that he did not have any seizure activity. His vital signs include: blood pressure 121/89 mm Hg, heart rate 89/min, temperature 37.0°C (98.6°F), and respiratory rate 16/min. Physical examination reveals a crescendo-decrescendo systolic murmur in the right second intercostal area. An electrocardiogram is performed, which shows left ventricular hypertrophy. Which of the following is the best next step for this patient?", "answer": "Transthoracic echocardiography", "options": {"A": "Cardiac chamber catheterization", "B": "Chest radiograph", "C": "Computed tomography (CT) chest scan without contrast", "D": "Transesophageal echocardiography", "E": "Transthoracic echocardiography"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old male presents to the emergency department due to severe headaches and palpitations. He has had previous episodes of sweating and headache, but this episode was particularly disabling. Upon presentation, he appears pale and diaphoretic. His temperature is 99.3°F (37.4°C), blood pressure is 162/118 mmHg, pulse is 87/min, and respirations are 20/min. Based on clinical suspicion, an abdominal CT scan is obtained, which shows a retroperitoneal mass. This patient's increased heart rate is most likely due to a change in activity of which of the following channels?", "answer": "Hyperpolarization-activated, nucleotide-gated channels", "options": {"A": "Hyperpolarization-activated, nucleotide-gated channels", "B": "L-type calcium channels", "C": "T-type calcium channels", "D": "Voltage-gated sodium channels", "E": "Voltage-gated potassium channels"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman presents to the labor and delivery floor in active labor at 40 weeks gestation. She has a prolonged course but ultimately vaginally delivers an 11 pound boy. On post operative day 2, she is noted to have uterine tenderness and decreased bowel sounds. She states she has been urinating more frequently as well. Her temperature is 102°F (38.9°C), blood pressure is 118/78 mmHg, pulse is 111/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for a non-distended abdomen and a tender uterus. Pulmonary exam reveals minor bibasilar crackles. Initial laboratory studies and a urinalysis are pending. Which of the following is the most likely diagnosis?", "answer": "Endometritis", "options": {"A": "Atelectasis", "B": "Chorioamnionitis", "C": "Deep vein thrombosis", "D": "Endometritis", "E": "Urinary tract infection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old farmer presents to his physician with a puncture wound on his left shin. He got this wound accidentally when he felt unwell and went out to his garden \"to catch some air\". He reports he had been treated for tetanus 35 years ago and has received the Tdap vaccine several times since then, but he does not remember when he last received the vaccine. His vital signs are as follows: the blood pressure is 110/80 mm Hg, heart rate is 91/min, respiratory rate is 19/min, and temperature is 37.8°C (100.0°F). On physical examination, he is mildly dyspneic and pale. Lung auscultation reveals diminished vesicular breath sounds in the lower lobes bilaterally with a few inspiratory crackles heard over the left lower lobe. There is a puncture wound 1 cm in diameter that is contaminated with soil in the middle third of the patient’s shin. You order blood tests and an X-ray, and now you are arranging his wound treatment. How should tetanus post-exposure prevention be performed in this case?", "answer": "The patient should receive both tetanus toxoid-containing vaccine and human tetanus immunoglobulin.", "options": {"A": "The patient should only be administered human tetanus immunoglobulin, because he is acutely ill and febrile, which are contraindications for tetanus toxoid-containing vaccine administration.", "B": "The patient does not need tetanus post-exposure prevention, because he has a past medical history of tetanus.", "C": "The patient does not need tetanus post-exposure prevention, because he received the Tdap vaccine several times in the past.", "D": "The patient should receive both tetanus toxoid-containing vaccine and human tetanus immunoglobulin.", "E": "The patient should be administered only the Tdap vaccine, because it is a minor wound with a small area of possible toxin absorption."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 74-year-old woman is brought to the physician by her husband because of difficulty sleeping for several years. She says that she has been gradually sleeping less each night over the past 2 years. It takes her 20–25 minutes to fall asleep each night and she wakes up earlier in the morning than she used to. On average, she sleeps 5–6 hours each night. She says that she has also been waking up several times per night and needs about 20 minutes before she is able to fall back to sleep. She feels mildly tired in the afternoon but does not take any naps. Her husband reports that she does not snore. The patient drinks two cups of coffee each morning, but she does not smoke or drink alcohol. She takes a 45 minute walk with her husband and their dog every other day. She is 160 cm (5 ft 3 in) tall and weighs 55 kg (121 lb); BMI is 21 kg/m2. Vital signs are within normal limits. On mental status examination, she appears cooperative with a mildly anxious mood and a full range of affect. Which of the following is the most appropriate next step in management?", "answer": "Reassurance", "options": {"A": "Sleep restriction", "B": "Flurazepam", "C": "Reassurance", "D": "Bilevel positive airway pressure (BiPAP)", "E": "Paradoxical intention"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 63-year-old man comes to the emergency department because of pain in his left groin for the past hour. The pain began soon after he returned from a walk. He describes it as 8 out of 10 in intensity and vomited once on the way to the hospital. He has had a swelling of the left groin for the past 2 months. He has chronic obstructive pulmonary disease and hypertension. Current medications include amlodipine, albuterol inhaler, and a salmeterol-fluticasone inhaler. He appears uncomfortable. His temperature is 37.4°C (99.3°F), pulse is 101/min, and blood pressure is 126/84 mm Hg. Examination shows a tender bulge on the left side above the inguinal ligament that extends into the left scrotum; lying down or applying external force does not reduce the swelling. Coughing does not make the swelling bulge further. There is no erythema. The abdomen is distended. Bowel sounds are hyperactive. Scattered rhonchi are heard throughout both lung fields. Which of the following is the most appropriate next step in management?", "answer": "Open surgical repair", "options": {"A": "Surgical drainage", "B": "Antibiotic therapy", "C": "Open surgical repair", "D": "Surgical exploration of the testicle", "E": "Laparoscopic surgical repair"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Certain glucose transporters that are expressed predominantly on skeletal muscle cells and adipocytes are unique compared to those transporters found on other cell types within the body. Without directly affecting glucose transport in other cell types, which of the following would be most likely to selectively increase glucose uptake in skeletal muscle cells and adipocytes?", "answer": "Increased levels of circulating insulin", "options": {"A": "Increased levels of circulating insulin", "B": "Decreased levels of circulating insulin", "C": "Increased plasma glucose concentration", "D": "Decreased plasma glucose concentration", "E": "It is physiologically impossible to selectively increase glucose uptake in specific cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 12-year-old boy presents to your office with facial swelling and dark urine. He has no other complaints other than a sore throat 3 weeks ago that resolved after 6 days. He is otherwise healthy, lives at home with his mother and 2 cats, has no recent history of travel ,and no sick contacts. On physical examination his temperature is 99°F (37.2°C), blood pressure is 130/85 mmHg, pulse is 80/min, respirations are 19/min, and pulse oximetry is 99% on room air. Cardiopulmonary and abdominal examinations are unremarkable. There is mild periorbital and pedal edema. Urinalysis shows 12-15 RBC/hpf, 2-5 WBC/hpf, and 30 mg/dL protein. Which additional finding would you expect to see on urinalysis?", "answer": "RBC casts", "options": {"A": "WBC casts", "B": "Granular casts", "C": "Hyaline", "D": "RBC casts", "E": "Fatty casts"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old male with a history of CHF presents to the emergency room with shortness of breath, lower leg edema, and fatigue. He is diagnosed with acute decompensated congestive heart failure, was admitted to the CCU, and treated with a medication that targets beta-1 adrenergic receptors preferentially over beta-2 adrenergic receptors. The prescribing physician explained that this medication would only be used temporarily as its efficacy decreases within one week due to receptor downregulation. Which of the following was prescribed?", "answer": "Dobutamine", "options": {"A": "Epinephrine", "B": "Milrinone", "C": "Isoproterenol", "D": "Norepinephrine", "E": "Dobutamine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old man presents to his primary care physician for his first appointment. He recently was released from prison. The patient wants a checkup before he goes out and finds a job. He states that lately he has felt very fatigued and has had a cough. He has lost roughly 15 pounds over the past 3 weeks. He attributes this to intravenous drug use in prison. His temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 100/min, respirations are 18/min, and oxygen saturation is 98% on room air. The patient is started on appropriate treatment. Which of the following is the most likely indication to discontinue this patient's treatment?", "answer": "Elevated liver enzymes", "options": {"A": "Elevated liver enzymes", "B": "Hyperuricemia", "C": "Optic neuritis", "D": "Peripheral neuropathy", "E": "Red body excretions"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old male presents for a routine health check-up. The patient complains of reduced exercise tolerance for the past 2 years. Also, in the past year, he has noticed chest pain after climbing the stairs in his home. He has no significant past medical history or current medications. The patient reports a 45-pack-year smoking history. The vital signs include temperature 37.0°C (98.6°F), blood pressure 160/100 mm Hg, pulse 72/min, respiratory rate 15/min, and oxygen saturation 99% on room air. His body mass index (BMI) is 34 kg/m2. Physical examination is unremarkable. Laboratory studies show:\nSerum total cholesterol 265 mg/dL\nHDL 22 mg/dL\nLDL 130 mg/dL\nTriglycerides 175 mg/dL \nHDL: high-density lipoprotein; LDL: low-density lipoprotein\nWhich of the following vascular pathologies is most likely present in this patient?", "answer": "Atherosclerosis", "options": {"A": "Medial calcific sclerosis", "B": "Lymphedema", "C": "Deep venous thrombosis", "D": "Hyperplastic arteriosclerosis", "E": "Atherosclerosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 88-year-old woman with no significant medical history is brought to the emergency room by her daughter after a fall, where the woman lightly hit her head against a wall. The patient is lucid and complains of a mild headache. The daughter indicates that her mother did not lose consciousness after the fall. On exam, there are no focal neurological deficits, but you decide to perform a CT scan to be sure there is no intracranial bleeding. The CT scan are within normal limits and head MRI is preformed (shown). Which of the following conditions has the most similar risk factor to this patient's condition?", "answer": "Thoracic aortic aneurysm", "options": {"A": "Prinzmetal's angina", "B": "Thoracic aortic aneurysm", "C": "Abdominal aortic aneurysm", "D": "Raynaud's phenomenon", "E": "Pulmonary embolism"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "While explaining the effects of hypokalemia and hyperkalemia on the cardiac rhythm, a cardiologist explains that the electrophysiology of cardiac tissue is unique. He mentions that potassium ions play an important role in the electrophysiology of the heart, and the resting membrane potential of the cardiac myocytes is close to the equilibrium potential of K+ ions. This is because of the high resting potassium conductance of the ventricular myocytes, which is regulated by specific potassium channels. These are open at rest and are closed when there is depolarization. Which of the following potassium channels is the cardiologist talking about?", "answer": "Inward rectifier IK1 potassium channels", "options": {"A": "Inward rectifier IK1 potassium channels", "B": "Inward rectifier IKACh potassium channels", "C": "Fast delayed rectifier IKr potassium channels", "D": "Slow delayed rectifier IKs potassium channels", "E": "Transient outward current Ito potassium channels"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old man presents to his dermatologist with white scaly papules and plaques on his extensor arms, elbows, knees, and shins. Scaly and flaky eruptions are also present on his ears, eyebrows, and scalp. He describes the lesions as being itchy and irritating. When the scales are scraped away, pinpoint bleeding is noted. His vital signs are unremarkable, and physical examination is otherwise within normal limits. Which of the following is the best initial test for this patient’s condition?", "answer": "No tests are necessary", "options": {"A": "Skin biopsy", "B": "Serum autoantibodies", "C": "Plain film X-rays of the hands and feet", "D": "No tests are necessary", "E": "Wood’s lamp"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old man presents with a mass on the central part of his neck. He reports it has been growing steadily for the past 2 weeks, and he has also been experiencing fatigue and recurrent fevers. No significant past medical history. The patient denies any smoking history, or alcohol or recreational drug use. He denies any recent travel in the previous 6 months. On physical examination, there are multiple enlarged submandibular and cervical lymph nodes that are firm, mobile, and non-tender. A biopsy of one of the lymph nodes is performed and shows predominantly lymphocytes and histiocytes present in a pattern ‘resembling popcorn’. A flow cytometry analysis demonstrates cells that are CD19 and CD20 positive and CD15 and CD30 negative. Which of the following is the most likely diagnosis in this patient?", "answer": "Nodular lymphocyte-predominant Hodgkin lymphoma", "options": {"A": "Lymphocyte rich classical Hodgkin lymphoma", "B": "Nodular lymphocyte-predominant Hodgkin lymphoma", "C": "Nodular sclerosis classical Hodgkin lymphoma", "D": "Mixed cellularity classical Hodgkin lymphoma", "E": "Lymphocyte depleted Hodgkin lymphoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3550-g (7-lb 13-oz) male newborn is delivered at 37 weeks' gestation to a 28-year-old woman. Apgar scores are 9 and 10 at 1 and 5 minutes, respectively. His vital signs are within normal limits. Physical examination shows no abnormalities. Routine neonatal screening tests show mildly elevated TSH concentrations. Ultrasonography of the neck shows a complete absence of both lobes of the thyroid gland. This patient's normal physical examination findings, despite the total absence of a thyroid gland, is best explained by which of the following mechanisms?", "answer": "Transplacental transmission of thyroxine", "options": {"A": "Transplacental transmission of thyroxine", "B": "Presence of lingual thyroid tissue", "C": "Molecular mimicry of hCG subunit", "D": "Production of TSH-receptor antibodies", "E": "Degradation of thyroid-binding globulin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-month-old boy is brought to the physician by his mother because of poor weight gain and irritability since delivery. He is at the 10th percentile for height and below the 5th percentile for weight. Physical examination shows conjunctival pallor. Laboratory studies show:\nHemoglobin 11.2 g/dL\nMean corpuscular hemoglobin 24.2 pg/cell\nMean corpuscular volume 108 μm3\nSerum\nAmmonia 26 μmol/L (N=11–35 μmol/L)\nA peripheral blood smear shows macrocytosis of erythrocytes and hypersegmented neutrophils. Supplementation with folate and cobalamin is begun. Two months later, his hemoglobin concentration is 11.1 g/dL and mean corpuscular volume is 107 μm3. The patient's condition is most likely caused by failure of which of the following enzymatic reactions?\"", "answer": "Orotate to uridine 5'-monophosphate", "options": {"A": "Ornithine and carbamoylphosphate to citrulline", "B": "Glucose-6-phosphate to 6-phosphogluconate", "C": "Hypoxanthine to inosine monophosphate", "D": "Phosphoenolpyruvate to pyruvate", "E": "Orotate to uridine 5'-monophosphate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 40-year-old woman comes to the physician because of a 3-day history of fever, headaches, and fatigue. She also reports a persistent tingling sensation in her right hand and numbness in her right arm that started this morning. Physical examination shows pallor, mild scleral icterus, and petechiae on her forearms and legs. On mental status examination, she appears confused and is only oriented to person. Laboratory studies show:\nHemoglobin 11.1 mg/dL\nPlatelet count 39,500/mm3\nBleeding time 9 minutes\nProthrombin time 14 seconds\nPartial thromboplastin time 35 seconds\nSerum\nCreatinine 1.7 mg/dL\nTotal bilirubin 2.1 mg/dL\nA peripheral blood smear shows fragmented erythrocytes. Which of the following is the most likely underlying cause of this patient's condition?\"", "answer": "Antibodies against ADAMTS13", "options": {"A": "Antibodies against ADAMTS13", "B": "Antibodies against GpIIb/IIIa", "C": "Absence of platelet GpIIb/IIIa receptors", "D": "Mutation of the PIGA gene", "E": "Antibodies against double-stranded DNA"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the office with a 2-week history of rectal bleeding that occurs every day with her bowel movements. She denies any pain during defecation. Apart from this, she does not have any other complaints. Her past medical history is insignificant except for 5 normal vaginal deliveries. Her vitals are a heart rate of 72/min, a respiratory rate of 15/min, a temperature of 36.7°C (98.1°F), and a blood pressure of 115/85 mm Hg. On rectovaginal examination, there is a palpable, non-tender, prolapsed mass that can be pushed back by the examiner's finger into the anal sphincter. What is the most likely diagnosis?", "answer": "Hemorrhoids", "options": {"A": "Anal fissure", "B": "Anorectal fistula", "C": "Rectal ulcer", "D": "Proctitis", "E": "Hemorrhoids"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old man comes to the physician’s office with jaundice. Liver ultrasound reveals a shrunken liver and biopsy reveals cirrhosis. Hepatitis serologies are below:\n\nAnti-HAV: negative\nHBsAg: negative\nHBsAb: positive\nHBeAg: negative\nAnti-HBe: negative\nAnti-HBc: negative\nAnti-HCV: positive\n\nThe hepatitis C viral load is 1,000,000 copies/mL. The patient is started on an antiviral regimen including sofosbuvir. What is the mechanism of action of this drug?", "answer": "Inhibits RNA-dependent RNA polymerase", "options": {"A": "Inhibits synthesis of DNA-dependent DNA polymerase", "B": "Inhibits hepatitis C protease", "C": "Inhibits reverse transcriptase", "D": "Inhibits integrase", "E": "Inhibits RNA-dependent RNA polymerase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old Chinese man presents to the office with a complaint of progressive unilateral nasal obstruction for 10 months. Though he was able to tolerate his symptoms at the beginning, he can’t breathe properly through the obstructed nostril anymore. Also, a bloody nasal discharge has started recently through the occluded nostril. He also complains of double vision during the past 2 months but did not pay attention to it until now. Past medical history is insignificant except for occasional sore throats.\nHis vitals include: blood pressure of 120/88 mm Hg, respiratory rate of 14/min, pulse of 88/min, temperature 37.0°C (98.6°F).\nBlood analysis shows:\nHemoglobin 15 g/dL\nHematocrit 46%\nLeukocyte count 15000/mm3\nNeutrophils 72%\nLymphocytes 25%\nMonocytes 3%\nMean corpuscular volume 95 fL\nPlatelet count 350,000/mm3\nWhich of the following viral etiology is most likely associated with the development of this patient’s condition?", "answer": "Epstein-Barr virus", "options": {"A": "Human papillomavirus", "B": "HIV", "C": "Epstein-Barr virus", "D": "Hepatitis B virus", "E": "Human T lymphotropic virus type I"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 78-year-old man is brought in to the emergency department by ambulance after his wife noticed that he began slurring his speech and had developed facial asymmetry during dinner approximately 30 minutes ago. His past medical history is remarkable for hypertension and diabetes. His temperature is 99.1°F (37.3°C), blood pressure is 154/99 mmHg, pulse is 89/min, respirations are 12/min, and oxygen saturation is 98% on room air. Neurologic exam reveals right upper and lower extremity weakness and an asymmetric smile. Which of the following is the next best step in management?", "answer": "CT head", "options": {"A": "Alteplase", "B": "Aspirin", "C": "CT head", "D": "CTA head", "E": "MRI brain"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-year-old boy is brought to the physician for recurrent 3–4 minutes episodes of facial grimacing and staring over the past month. He is nonresponsive during these episodes and does not remember them afterward. He recalls a muddy taste in his mouth before the onset of symptoms. One week ago, his brother witnessed an episode where he woke up, stared, and made hand gestures. After the incident, he felt lethargic and confused. Examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Complex partial seizure", "options": {"A": "Absence seizures", "B": "Myoclonic seizure", "C": "Simple partial seizures", "D": "Breath-holding spell", "E": "Complex partial seizure"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A group of scientists is studying the mechanism by which the human papillomavirus (HPV) vaccine confers immunity. They observe that during the inoculation of test subjects, mammals with certain viral proteins result in the organism’s antigen-presenting cells (APCs) absorbing the antigen and presenting it on major histocompatibility complex (MHC) class 1 molecules. Which of the following is the correct term for the process that the scientists are observing in this inoculation?", "answer": "Cross-presentation", "options": {"A": "Endogenous antigen presentation", "B": "Cross-presentation", "C": "Priming of CD4+ T cells", "D": "Adhesion", "E": "Ubiquitination"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 21-year-old woman presents with the complaints of nausea, vomiting, and diarrhea for 5 days. She adds that she has fever and abdominal cramping as well. She had recently attended a large family picnic and describes eating many varieties of cold noodle salads. Her past medical history is insignificant. Her temperature is 37.5°C (99.6°F), respiratory rate is 15/min, pulse is 67/min, and blood pressure is 92/68 mm Hg. Physical examination is non-contributory. Given the clinical information provided and most likely diagnosis, which of the following would be the next best step in the management of this patient?", "answer": "Replacement of fluids and electrolytes", "options": {"A": "IV antibiotic therapy to prevent disseminated disease", "B": "Replacement of fluids and electrolytes", "C": "Empiric therapy assuming multi-drug resistance", "D": "Short course of oral antibiotics to prevent asymptomatic carrier state", "E": "Prolonged oral antibiotics"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying biomolecular mechanisms in human cells. A radioactive isotope that is unable to cross into organelles is introduced into a sample of cells. The cells are then fragmented via centrifugation and the isotope-containing components are isolated. Which of the following reactions is most likely to be present in this cell component?", "answer": "Glucose-6-phosphate to 6-phosphogluconolactone", "options": {"A": "Glucose-6-phosphate to glucose", "B": "Fatty acyl-CoA to acetyl-CoA", "C": "Carbamoyl phosphate to citrulline", "D": "Glucose-6-phosphate to 6-phosphogluconolactone", "E": "Isocitrate to α-ketoglutarate"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old man comes to the physician for his annual health maintenance examination. The patient has no particular health concerns. He has a history of bilateral cryptorchidism treated with orchidopexy at 8 months of age. This patient is at increased risk for which of the following?", "answer": "Teratocarcinoma", "options": {"A": "Teratocarcinoma", "B": "Sertoli cell tumor", "C": "Leydig cell tumor", "D": "Yolk sac tumor", "E": "Testicular lymphoma\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman comes to the emergency department because of a 2-day history of dark urine, increasing abdominal pain, and a tingling sensation in her arms and legs. She has a history of epilepsy. Her current medication is phenytoin. She is nauseated and confused. Following the administration of hemin and glucose, her symptoms improve. The beneficial effect of this treatment is most likely due to inhibition of which of the following enzymes?", "answer": "Aminolevulinate acid synthase", "options": {"A": "Aminolevulinate dehydratase", "B": "Aminolevulinate acid synthase", "C": "Ferrochelatase", "D": "Porphobilinogen deaminase", "E": "Uroporphyrinogen decarboxylase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the emergency department by his parents because of fever and recurrent episodes of jerky movements of his extremities for the past 6 hours. Pregnancy and delivery were uncomplicated, and development was normal until the age of 1 year. The parents report that he has had gradual loss of speech, vision, and motor skills over the past year. During this time, he has been admitted to the hospital three times because of myoclonic seizures. Physical examination shows hypertonicity of the upper and lower extremities. Fundoscopic examination shows pallor of the optic disc bilaterally. An MRI of the brain shows brain atrophy and hyperintensity of the periventricular and subcortical areas. Two days after admission, the patient dies. Histopathologic examination of the brain shows aggregation of globoid cells and loss of glial cells. The patient’s condition was most likely caused by a deficiency of which of the following enzymes?", "answer": "β-Galactocerebrosidase", "options": {"A": "Sphingomyelinase", "B": "Arylsulfatase A", "C": "β-Glucocerebrosidase", "D": "β-Hexosaminidase A", "E": "β-Galactocerebrosidase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An obese, 66-year-old woman comes to the physician for a routine health maintenance examination. She feels well but is unhappy about being overweight. She reports that she feels out of breath when walking for more than one block and while climbing stairs. She has tried to lose weight for several years without success. She goes for a walk 3 times a week but she has difficulty following a low-calorie diet. During the past 12 months, she has had two urinary tract infections that were treated with fosfomycin. She has type 2 diabetes mellitus and osteoarthritis. Her only current medication is metformin. She has never smoked. She is 160 cm (5 ft 3 in) tall and weighs 100 kg (220 lb); BMI is 39.1 kg/m2. Vital signs are within normal limits. Physical examination shows cracking in both knees on passive movement. The remainder of the examination shows no abnormalities. Serum studies show an HbA1c of 9.5%, and a fasting serum glucose concentration of 158 mg/dL. An ECG shows no abnormalities. Which of the following is the most appropriate pharmacotherapy?", "answer": "Exenatide", "options": {"A": "Topiramate", "B": "Exenatide", "C": "Pioglitazone", "D": "Acarbose", "E": "Phentermine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old man comes to the physician for a follow-up examination. One month ago, therapy with lisinopril was initiated for treatment of hypertension. His blood pressure is 136/86 mm Hg. Urinalysis shows a creatinine clearance of 92 mL/min. The patient's serum creatinine concentration is most likely closest to which of the following values?", "answer": "1.1 mg/dL", "options": {"A": "1.4 mg/dL", "B": "2.3 mg/dL", "C": "2.0 mg/dL", "D": "1.1 mg/dL", "E": "1.7 mg/dL"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 21-year-old woman presents to the emergency department with complaints of intermittent bouts of lower abdominal and pelvic pain over the last week. The pain is primarily localized to the right side and is non-radiating. The patient is not sexually active at this time and is not currently under any medication. At the hospital, her vitals are normal. A pelvic examination reveals a tender palpable mass on the right adnexal structure. A pelvic CT scan reveals a 7-cm solid adnexal mass that was surgically removed with the ovary. Histological evaluation indicates sheets of uniform cells resembling a 'fried egg', consistent with dysgerminoma. Which of the following tumor markers is most likely elevated with this type of tumor?", "answer": "Lactate dehydrogenase (LDH)", "options": {"A": "Lactate dehydrogenase (LDH)", "B": "Beta-human chorionic gonadotropin (beta-hCG)", "C": "Alpha-fetoprotein (AFP)", "D": "Inhibin A", "E": "Cancer antigen 125 (CA-125)"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old woman, gravida 2, para 1, comes to the physician for her initial prenatal visit at 18 weeks’ gestation. She is a recent immigrant from Thailand. Her history is significant for anemia since childhood that has not required any treatment. Her mother and husband have anemia, as well. She has no history of serious illness and takes no medications. Her vital signs are within normal limits. Fundal height measures at 22 weeks. Ultrasound shows polyhydramnios and pleural and peritoneal effusion in the fetus with fetal subcutaneous edema. Which of the following is the most likely clinical course for this fetus?", "answer": "Intrauterine fetal demise", "options": {"A": "Asymptomatic anemia", "B": "Carrier state", "C": "Intrauterine fetal demise", "D": "Neonatal death", "E": "Normal development with regular blood transfusion"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 62-year-old woman comes to the physician because of increasing blurring of vision in both eyes. She says that the blurring has made it difficult to read, although she has noticed that she can read a little better if she holds the book below or above eye level. She also requires a bright light to look at objects. She reports that her symptoms began 8 years ago and have gradually gotten worse over time. She has hypertension and type 2 diabetes mellitus. Current medications include glyburide and lisinopril. When looking at an Amsler grid, she says that the lines in the center appear wavy and bent. An image of her retina, as viewed through fundoscopy is shown. Which of the following is the most likely diagnosis?", "answer": "Age-related macular degeneration\n\"", "options": {"A": "Central serous retinopathy", "B": "Hypertensive retinopathy", "C": "Diabetic retinopathy", "D": "Cystoid macular edema", "E": "Age-related macular degeneration\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 50-year-old woman presents with esophageal varices, alcoholic cirrhosis, hepatic encephalopathy, portal hypertension, and recent onset confusion. The patient’s husband does not recall her past medical history but knows her current medications and states that she is quite disciplined about taking them. Current medications are spironolactone, labetalol, lactulose, and furosemide. Her temperature is 38.3°C (100.9°F), heart rate is 115/min, blood pressure is 105/62 mm Hg, respiratory rate is 12/min, and oxygen saturation is 96% on room air. On physical examination, the patient is disoriented, lethargic, and poorly responsive to commands. A cardiac examination is unremarkable. Lungs are clear to auscultation. The abdomen is distended, tense, and mildly tender. Mild asterixis is present. Neurologic examination is normal. The digital rectal examination reveals guaiac negative stool. Laboratory findings are significant for the following:\nBasic metabolic panel Unremarkable\nPlatelet count 95,500/µL\nLeukocyte count 14,790/µL\nHematocrit 33% (baseline is 30%)\nWhich of the following would most likely be of diagnostic value in this patient?", "answer": "Abdominal paracentesis", "options": {"A": "Noncontrast CT of the head", "B": "Therapeutic trial of lactulose", "C": "Esophagogastroduodenoscopy", "D": "Abdominal paracentesis", "E": "Serum ammonia level"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman is brought to the emergency department 8 hours after the sudden onset of shortness of breath and pleuritic chest pain. She has cystic fibrosis and, during the past year, has had 4 respiratory exacerbations that have required hospitalization. Current medications include an inhaled bronchodilator, an inhaled corticosteroid, inhaled N-acetylcysteine, and azithromycin. The patient appears chronically ill. Her temperature is 37.9°C (100.2°F), pulse is 96/min, respirations are 22/min and labored, and blood pressure is 106/64 mm Hg. Pulse oximetry on 2 L/min of oxygen via nasal cannula shows an oxygen saturation of 96%. Examination shows an increased anteroposterior chest diameter. There is digital clubbing. Chest excursions and tactile fremitus are decreased on the right side. On auscultation of the chest, breath sounds are significantly diminished over the right lung field and diffuse wheezing is heard over the left lung field. Which of the following is the most likely underlying cause of this patient's current symptoms?", "answer": "Apical subpleural cyst", "options": {"A": "Bronchial hyperresponsiveness", "B": "Inflammation of costal cartilage", "C": "Infection with gram-negative coccobacilli", "D": "Apical subpleural cyst", "E": "Increased pulmonary capillary permeability"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 61-year-old diabetic woman is brought to the emergency department with the complaint of multiple bouts of abdominal pain in the last 24 hours. She says that the pain is dull aching in nature, radiates to the back, and worsens with meals. She also complains of nausea and occasional vomiting. She has been hospitalized repeatedly in the past with similar complaints. Her temperature is 37° C (98.6° F), respiratory rate is 16/min, pulse is 77/min, and blood pressure is 120/89 mm Hg. On physical exam, dark hyperpigmentation of the axillary skin is noted. Her blood test report from last month is given below:\nGlycated hemoglobin (HbA1c): 9.1%\nTriglyceride: 675 mg/dL\nLDL-Cholesterol: 102 mg/dL\nHDL-Cholesterol: 35 mg/dL\nTotal Cholesterol: 250 mg/dL\nSerum Creatinine: 1.2 mg/dL\nBUN:  12 mg/dL\nAlkaline phosphatase: 100 U/L\nAlanine aminotransferase: 36 U/L\nAspartate aminotransferase: 28 U/L\nWhat is the most likely diagnosis in this case?", "answer": "Pancreatitis", "options": {"A": "Cholecystitis", "B": "Choledocholithiasis", "C": "Pancreatitis", "D": "Duodenal peptic ulcer", "E": "Gallbladder cancer"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 82-year-old woman is admitted to the hospital because of wet gangrene on her right leg. Two days after admission, she becomes increasingly confused and tachypneic. She is intubated and ventilatory support is initiated. Her temperature is 39.6°C (102.5°F), pulse is 127/min, and blood pressure is 83/47 mm Hg. The ventilator is set at a FiO2 of 100% and a respiratory rate of 20/min. An arterial blood gas checked 30 minutes after intubation shows a PCO2 of 41 mm Hg and a PO2 of 55 mm Hg. Despite appropriate care, the patient dies from respiratory failure. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Fluid in the alveolar space", "options": {"A": "Hyperinflation of the lungs", "B": "Emboli in the pulmonary vasculature", "C": "Nodular thickening of the interlobular septa", "D": "Abscess in the lung parenchyma", "E": "Fluid in the alveolar space"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 57-year-old florist presents to his family physician with nodular lesions on his right hand and forearm. He explains that he got pricked by a rose thorn on his right \"pointer finger\" where the first lesions appeared, and the other lesions then began to appear in an ascending manner. The physician prescribed a medication and warned him of gynecomastia as a side effect if taken for long periods of time. Which of the following is the mechanism of action of the medication?", "answer": "Inhibits ergosterol synthesis", "options": {"A": "Inhibits ergosterol synthesis", "B": "Binds to ergosterol, forming destructive pores in cell membrane", "C": "Inhibits squalene epoxidase", "D": "Inhibits formation of beta glucan", "E": "Disrupts microtubule function"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 58-year-old woman presents to the physician’s office with vaginal bleeding. The bleeding started as a spotting and has increased and has become persistent over the last month. The patient is G3P1 with a history of polycystic ovary syndrome and type 2 diabetes mellitus. She completed menopause 4 years ago. She took cyclic estrogen-progesterone replacement therapy for 1 year at the beginning of menopause. Her weight is 89 kg (196 lb), height 157 cm (5 ft 2 in). Her vital signs are as follows: blood pressure 135/70 mm Hg, heart rate 78/min, respiratory rate 12/min, and temperature 36.7℃ (98.1℉). Physical examination is unremarkable. Transvaginal ultrasound reveals an endometrium of 6 mm thickness. Speculum examination shows a cervix without focal lesions with bloody discharge from the non-dilated external os. On pelvic examination, the uterus is slightly enlarged, movable, and non-tender. Adnexa is non-palpable. What is the next appropriate step in the management of this patient?", "answer": "Endometrial biopsy", "options": {"A": "Hysteroscopy with dilation and curettage", "B": "Medroxyprogesterone acetate therapy", "C": "Endometrial biopsy", "D": "Saline infusion sonography", "E": "Hysteroscopy with targeted biopsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A student is reviewing the various effects that can be plotted on a dose-response curve. He has observed that certain drugs can work as an agonist and an antagonist at a particular site. He has plotted a particular graph (as shown below) and is checking for other responses that can be measured on the same graph. He learned that drug B is less potent than drug A. Drug B also reduces the potency of drug A when combined in the same solution; however, if additional drug A is added to the solution, the maximal efficacy (Emax) of drug A increases. He wishes to plot another curve for drug C. He learns that drug C works on the same molecules as drugs A and B, but drug C reduces the maximal efficacy (Emax) of drug A significantly when combined with drug A. Which of the following best describes drug C?", "answer": "Non-competitive antagonist", "options": {"A": "Competitive antagonist", "B": "Non-competitive antagonist", "C": "Inverse agonist", "D": "Full agonist", "E": "Reversible antagonist"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "You are seeing a patient in clinic who recently started treatment for active tuberculosis. The patient is currently being treated with rifampin, isoniazid, pyrazinamide, and ethambutol. The patient is not used to taking medicines and is very concerned about side effects. Specifically regarding the carbohydrate polymerization inhibiting medication, which of the following is a known side effect?", "answer": "Vision loss", "options": {"A": "Cutaneous flushing", "B": "Elevated liver enzymes", "C": "Paresthesias of the hands and feet", "D": "Vision loss", "E": "Arthralgias"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man visits his primary care physician for a routine health maintenance examination. During the examination, he expresses concerns about not wanting to become a father. He has been sexually active and monogamous with his wife for the past 5 years, and they inconsistently use condoms for contraception. He tells the physician that he would like to undergo vasectomy. His wife is also a patient under the care of the physician and during her last appointment, she expressed concerns over being prescribed any drugs that could affect her fertility because she would like to conceive soon. Which of the following is the most appropriate action by the physician regarding this patient's wish to undergo vasectomy?", "answer": "Explain the procedure's benefits, alternatives, and potential complications", "options": {"A": "Insist that the patient returns with his wife to discuss the risks and benefits of the procedure together", "B": "Explain the procedure's benefits, alternatives, and potential complications", "C": "Refer the patient to a psychotherapist to discuss his reluctance to have children", "D": "Call the patient's wife to obtain her consent for the procedure", "E": "Discourage the patient from undergoing the procedure because his wife wants children"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old man is brought to the emergency department by his wife 20 minutes after she witnessed him vigorously shaking for about 1 minute. During this episode, he urinated on himself. He feels drowsy and has nausea. He has a history of chronic alcoholism; he has been drinking 15 beers daily for the past 3 days. Before this time, he drank 8 beers daily. His last drink was 2 hours ago. He appears lethargic. His vital signs are within normal limits. Physical and neurologic examinations show no other abnormalities. On mental status examination, he is confused and not oriented to time. Laboratory studies show:\nHematocrit 44.0%\nLeukocyte count 12,000/mm3\nPlatelet count 320,000/mm3\nSerum\nNa+ 112 mEq/L\nCl- 75 mEq/L\nK+ 3.8 mEq/L\nHCO3- 13 mEq/L\nUrea nitrogen 6 mEq/L\nCreatinine 0.6 mg/dL\nAlbumin 2.1 g/dL\nGlucose 80 mg/dL\nUrgent treatment for this patient's current condition puts him at increased risk for which of the following adverse events?\"", "answer": "Osmotic myelinolysis", "options": {"A": "Cerebral edema", "B": "Cardiac arrhythmia", "C": "Hyperglycemia", "D": "Osmotic myelinolysis", "E": "Wernicke encephalopathy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old man presents early in the morning to the emergency department with a burning sensation in his chest. He describes a crushing feeling below the sternum and reports some neck pain on the left side. Furthermore, he complains of difficulty breathing. Late last night, he had come home and had eaten a family size lasagna by himself while watching TV. His past medical history is significant for type 2 diabetes and poorly controlled hypertension. The patient admits he often neglects to take his medications and has not been following his advised diet. His current medications are aspirin, metformin, and captopril. Examination reveals a distressed, overweight male sweating profusely. Which of the following is most likely to be found on auscultation?", "answer": "Fourth heart sound", "options": {"A": "Diminished breath sounds", "B": "Ejection systolic murmur", "C": "Expiratory wheezes", "D": "Fixed splitting of the second heart sound", "E": "Fourth heart sound"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 76-year-old man is brought to the emergency room because of one episode of hemoptysis. His pulse is 110/min. Physical examination shows pallor; there is blood in the oral cavity. Examination of the nasal cavity with a nasal speculum shows active bleeding from the posterior nasal cavity. Tamponade with a balloon catheter is attempted without success. The most appropriate next step in the management is ligation of a branch of a vessel of which of the following arteries?", "answer": "Maxillary artery", "options": {"A": "Ophthalmic artery", "B": "Anterior cerebral artery", "C": "Facial artery", "D": "Occipital artery", "E": "Maxillary artery"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A researcher is studying how arachidonic acid metabolites mediate the inflammatory response in rats. She has developed multiple enzyme inhibitors that specifically target individual proteins in the arachidonic acid pathway. She injects these inhibitors in rats who have been exposed to common bacterial pathogens and analyzes their downstream effects. In one of her experiments, she injects a leukotriene B4 inhibitor into a rat and observes an abnormal cell response. Which of the following interleukins would most closely restore the function of one of the missing products?", "answer": "Interleukin 8", "options": {"A": "Interleukin 1", "B": "Interleukin 2", "C": "Interleukin 4", "D": "Interleukin 5", "E": "Interleukin 8"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old man comes to the physician because of recurrent episodes of chest pain, shortness of breath, palpitations, and a sensation of choking. The symptoms usually resolve with deep breathing exercises after about 5 minutes. He now avoids going to his graduate school classes because he is worried about having another episode. Physical examination is unremarkable. Treatment with lorazepam is initiated. The concurrent intake of which of the following drugs should be avoided in this patient?", "answer": "Diphenhydramine", "options": {"A": "Diphenhydramine", "B": "Phenelzine", "C": "Naloxone", "D": "Fluoxetine", "E": "Ondansetron"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old girl with a BMI of 14.5 kg/m2 is admitted to the hospital for the treatment of anorexia nervosa. The patient is administered intravenous fluids and is supplied with 1,600 calories daily with an increase of 200 calories each day. On day 5 of treatment, the patient manifests symptoms of weakness and confusion, and dark brown urine. Which of the following clinical conditions is the most likely cause of the patient's symptoms?", "answer": "Hypophosphatemia", "options": {"A": "Hypercalcemia", "B": "Hyperkalemia", "C": "Hypermagnesemia", "D": "Hypophosphatemia", "E": "Thiamine deficiency"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old woman is brought to the emergency department after being involved in a rear-end collision, in which she was the restrained driver of the back car. On arrival, she is alert and active. She reports pain in both knees and severe pain over the right groin. Temperature is 37°C (98.6°F), pulse is 116/min, respirations are 19/min, and blood pressure is 132/79 mm Hg. Physical examination shows tenderness over both knee caps. The right groin is tender to palpation. The right leg is slightly shortened, flexed, adducted, and internally rotated. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Posterior hip dislocation", "options": {"A": "Femoral neck fracture", "B": "Anterior hip dislocation", "C": "Femoral shaft fracture", "D": "Posterior hip dislocation", "E": "Pelvic fracture\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying human genetics and cell division. A molecule is used to inhibit the exchange of genetic material between homologous chromosomes. Which of the following phases of the cell cycle does the molecule target?", "answer": "Prophase I", "options": {"A": "Telophase I", "B": "Metaphase II", "C": "Prophase II", "D": "Prophase I", "E": "Anaphase I"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is studying neuronal regeneration. For microscopic visualization of the neuron, an aniline stain is applied. After staining, only the soma and dendrites of the neurons are visualized, not the axon. Presence of which of the following cellular elements best explains this staining pattern?", "answer": "Rough endoplasmic reticulum", "options": {"A": "Microtubule", "B": "Nucleus", "C": "Lysosome", "D": "Golgi apparatus", "E": "Rough endoplasmic reticulum"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 67-year-old woman presents to a surgeon with a painless, slowly growing ulcer in the periauricular region for the last 2 months. On physical examination, there is an irregular-shaped ulcer, 2 cm x 1 cm in its dimensions, with irregular margins and crusting over the surface. The woman is a fair-skinned individual who loves to go sunbathing. There is no family history of malignancy. After a complete physical examination, the surgeon performs a biopsy of the lesion under local anesthesia and sends the tissue for histopathological examination. The pathologist confirms the diagnosis of squamous cell carcinoma of the skin. When she asks about the cause, the surgeon explains that there are many possible causes, but it is likely that she has developed squamous cell carcinoma on her face due to repeated exposure to ultraviolet rays from the sun, especially ultraviolet B (UVB) rays. If the surgeon’s opinion is correct, which of the following mechanisms is most likely involved in the pathogenesis of the condition?", "answer": "Intrastrand cross-linking of thymidine residues in DNA", "options": {"A": "Intrastrand cross-linking of thymidine residues in DNA", "B": "Gain-of-function mutations of TP53", "C": "Upregulation of expression of cyclin D2", "D": "Activation of transcription factor NF-κB", "E": "DNA damage caused by the formation of reactive oxygen species"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old man presents to the physician with profuse watery diarrhea along with fever and crampy abdominal pain. He has been taking an antibiotic course of cefixime for about a week to treat a respiratory tract infection. At the doctor’s office, his pulse is 112/min, the blood pressure is 100/66 mm Hg, the respirations are 22/min, and the temperature is 38.9°C (102.0°F). His oral mucosa appears dry and his abdomen is soft with vague diffuse tenderness. A digital rectal examination is normal. Laboratory studies show:\nHemoglobin 11.1 g/dL\nHematocrit 33%\nTotal leucocyte count 16,000/mm3\nSerum lactate 0.9 mmol/L\nSerum creatinine 1.1 mg/dL\nWhat is most likely to confirm the diagnosis?", "answer": "Identification of C. difficile toxin in stool", "options": {"A": "Identification of C. difficile toxin in stool", "B": "Stool culture", "C": "Colonoscopy", "D": "Abdominal X-ray", "E": "CT scan of the abdomen"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man presents to the emergency department with fever and easy bruising for 3 days. He has had fatigue for 2 weeks. He has no past medical history, and takes no medications. Excessive bleeding from intravenous lines was reported by the nurse. He does not smoke or drink alcohol. The temperature is 38.2°C (102.6°F), pulse is 105/min, respiration rate is 18/min, and blood pressure is 110/70 mm Hg. On physical examination, he has multiple purpura on the lower extremities and several ecchymoses on the lower back and buttocks. Petechiae are noticed on the soft palate. Cervical painless lymphadenopathy is detected on both sides. The examination of the lungs, heart, and abdomen shows no other abnormalities. The laboratory test results are as follows:\nHemoglobin 8 g/dL\nMean corpuscular volume 90 μm3\nLeukocyte count 18,000/mm3\nPlatelet count 10,000/mm3\nPartial thromboplastin time (activated) 60 seconds\nProthrombin time 25 seconds (INR: 2.2)\nFibrin split products Positive\nLactate dehydrogenase, serum 1,000 U/L\nA Giemsa-stained peripheral blood smear is shown by the image. Intravenous fluids, blood products, and antibiotics are given to the patient. Based on the most likely diagnosis, which of the following is the best therapy for this patient at this time?", "answer": "All-trans retinoic acid (ATRA)", "options": {"A": "All-trans retinoic acid (ATRA)", "B": "Citarubin plus daunorubicin", "C": "Hematopoietic cell transplantation", "D": "Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP)", "E": "Adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD)"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-month-old is brought to the physician for a well-child examination. She was born at 39 weeks gestation via spontaneous vaginal delivery and is exclusively breastfed. She weighed 3,400 g (7 lb 8 oz) at birth. At the physician's office, she appears well. Her pulse is 136/min, the respirations are 41/min, and the blood pressure is 82/45 mm Hg. She weighs 5,200 g (11 lb 8 oz) and measures 57.5 cm (22.6 in) in length. The remainder of the physical examination is normal. Which of the following developmental milestones has this patient most likely met?", "answer": "Smiles in response to face", "options": {"A": "Absence of asymmetric tonic neck reflex", "B": "Monosyllabic babble", "C": "Reaches for objects", "D": "Smiles in response to face", "E": "Stares at own hand"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old female comes in with several months of unintentional weight loss, epigastric pain, and a sensation of abdominal pressure. She has diabetes well-controlled on metformin but no other prior medical history. She has not previously had any surgeries. On physical exam, her doctor notices brown velvety areas of pigmentation on her neck. Her doctor also notices an enlarged, left supraclavicular node. Endoscopic findings show a stomach wall that appears to be grossly thickened. Which of the following findings would most likely be seen on biopsy?", "answer": "Cells with central mucin pool", "options": {"A": "Cells with central mucin pool", "B": "Keratin pearls", "C": "Psammoma bodies", "D": "Peyer's patches", "E": "Noncaseating granulomas"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought to the emergency room by ambulance, accompanied by his kindergarten teacher. Emergency department staff attempt to call his parents, but they cannot be reached. The boy’s medical history is unknown. According to his teacher, the boy was eating in the cafeteria with friends when he suddenly complained of itching and developed a widespread rash. Physical exam is notable for diffuse hives and tongue edema. His pulse is 100/min and blood pressure is 90/60 mmHg. The boy appears frightened and tells you that he does not want any treatment until his parents arrive. Which of the following is the next best step in the management of this patient?", "answer": "Immediately administer epinephrine and sedate and intubate the patient", "options": {"A": "Continue calling the patient’s parents and do not intubate until verbal consent is obtained over the phone", "B": "Immediately administer epinephrine and sedate and intubate the patient", "C": "Obtain written consent to intubate from the patient’s teacher", "D": "Obtain written consent to intubate from the patient", "E": "Wait for the patient's parents to arrive, calm the patient, and provide written consent before intubating"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-month-old boy is brought to the physician for a well-child examination. He was born at 38 weeks' gestation and was 48 cm (19 in) in length and weighed 3061 g (6 lb 12 oz); he is currently 60 cm (24 in) in length and weighs 7,910 g (17 lb 7 oz). He can walk with one hand held and can throw a small ball. He can pick up an object between his thumb and index finger. He can wave 'bye-bye'. He can say 'mama', 'dada' and 'uh-oh'. He cries if left to play with a stranger alone. Physical examination shows no abnormalities. Which of the following is most likely delayed in this child?", "answer": "Growth", "options": {"A": "Language skills", "B": "Gross motor skills", "C": "Growth", "D": "Fine motor skills", "E": "Social skills"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old woman presents to the emergency department with right lower quadrant abdominal pain and vaginal spotting. She denies diarrhea, constipation, or blood in the stool. The medical history is unremarkable. She does not use tobacco or drink alcohol. She is sexually active with her husband and uses an IUD for contraception. The temperature is 37.2 °C (99.0°F), the blood pressure is 110/70 mm Hg, the pulse is 80/min, and the respiratory rate is 12/min. The physical examination reveals localized tenderness in the right adnexa, but no masses are palpated. The LMP was 8 weeks ago. Which of the following is most likely associated with this patient’s diagnosis?", "answer": "Positive urinary beta-HCG and no intrauterine mass", "options": {"A": "Physical examination reveals rebound tenderness and tenderness at McBurney’s point", "B": "Positive urinary beta-HCG and no intrauterine mass", "C": "Abdominal x-ray shows free air under the diaphragm", "D": "Barium enema shows true diverticuli in the colon", "E": "Positive urinary beta-HCG and some products of conception in the uterus"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old man with a past medical history of diabetes, hypertension, and hyperlipidemia was brought into the emergency department by his wife after she observed him go without sleep for several days and recently open and max out several credit cards. She also reports that he has quit his bartending job and has been excessively talkative and easily annoyed for the last several weeks. The patient has no previous psychiatric history. Routine medical examination, investigations, and toxicology rule out a medical cause or substance abuse. Lab results are consistent with chronically impaired renal function. What is the single best treatment for this patient?", "answer": "Valproic acid", "options": {"A": "Valproic acid", "B": "Lithium", "C": "Gabapentin", "D": "Pregabalin", "E": "Lamotrigine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman comes to the physician for the evaluation of a 1-month history of dull lower abdominal pain, decreased appetite, and a 5-kg (11-lb) weight loss. Physical examination shows no abnormalities. Pelvic ultrasonography shows bilateral ovarian enlargement and free fluid in the rectouterine pouch. Biopsy specimens from the ovaries show multiple, round, mucin-filled cells with flat, peripheral nuclei. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Gastric wall thickening", "options": {"A": "Decreased TSH levels", "B": "Increased testosterone levels", "C": "Dark blue peritoneal spots", "D": "Gastric wall thickening", "E": "Elevated β-hCG levels"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 71-year-old man presents to the clinic with complaints of right wrist pain for 2 days. On examination, redness and swelling were noted on the dorsal aspect of his right wrist. He had  pain with extreme range of motion of the wrist. His history includes 2 hip replacements, 2 previous episodes of gout in both first metatarsophalangeal joints, and hypertension. Two days later, the swelling had increased in the dorsal aspect of his right wrist and hand. Wrist flexion was limited to 80% with severe pain. The pain was present on palpation of the scaphoid bone. Due to the suspicion of fracture, the patient was referred to his general practitioner for radiographs. These findings were consistent with gouty arthritis. What is the most likely cytokine involved in this process?", "answer": "IL-1", "options": {"A": "IL-1", "B": "IL-10", "C": "INFγ", "D": "IL-4", "E": "IL-5"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A group of investigators have conducted a randomized clinical trial to evaluate the efficacy of adding a novel adenosine A1 receptor agonist to the standard anti-epileptic treatment in reducing the frequency of focal seizures. It was found that patients taking the combination regimen (n = 200) had a lower seizure frequency compared to patients taking the standard treatment alone (n = 200; p < 0.01). However, several participants taking the novel drug reported severe drowsiness. The investigators administered a survey to both the combination treatment group and standard treatment group to evaluate whether the drowsiness interfered with daily functioning using a yes or no questionnaire. Results are shown:\nInterference with daily functioning Yes (number of patients) No (number of patients)\nCombination treatment group 115 85\nStandard treatment group 78 122\nWhich of the following statistical methods would be most appropriate for assessing the statistical significance of these results?\"", "answer": "Chi-square test", "options": {"A": "Multiple linear regression", "B": "Chi-square test", "C": "Unpaired t-test", "D": "Paired t-test", "E": "Analysis of variance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 39-year-old male presents to your office with nodular skin lesions that progress from his right hand to right shoulder. The patient reports that the initial lesion, currently necrotic and ulcerative, developed from an injury he received while weeding his shrubs a couple weeks earlier. The patient denies symptoms of respiratory or meningeal disease. Which of the following most likely characterizes the pattern of this patient’s skin lesions:", "answer": "Ascending lymphangitis", "options": {"A": "Contact dermatitis", "B": "Hematogenous dissemination", "C": "Dermatophyte colonization", "D": "Ascending lymphangitis", "E": "Arthropod bite"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old Latin American woman with no significant past medical history or family history presents to her pediatrician with concerns about several long-standing skin lesions. She notes that she has had a light-colored rash on her chest and abdomen that has been present for the last 2 years. The blood pressure is 111/81 mm Hg, pulse is 82/min, respiratory rate is 16/min, and temperature is 37.3°C (99.1°F). Physical examination reveals numerous hypopigmented macules over her chest and abdomen. No lesions are seen on her palms or soles. When questioned, she states that these lesions do not tan like the rest of her skin when exposed to the sun. The remainder of her review of systems is negative. What is the most likely cause of these lesions?", "answer": "Malassezia yeast", "options": {"A": "Malassezia yeast", "B": "Cutaneous T cell lymphoma", "C": "Post-viral immunologic reaction", "D": "TYR gene dysfunction in melanocytes", "E": "Treponema pallidum infection"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old male presents to the emergency room complaining of severe diarrhea. He recently returned from a business trip to Bangladesh. Since returning, he has experienced several loose bloody stools per day that are accompanied by abdominal cramping and occasional nausea and vomiting. His temperature is 101.7°F (38.7°C), blood pressure is 100/60 mmHg, pulse is 120/min, and respirations are 20/min. On examination, he demonstrates mild tenderness to palpation throughout his abdomen, delayed capillary refill, and dry mucus membranes. Results from a stool sample and subsequent stool culture are pending. What is the mechanism of action of the toxin elaborated by the pathogen responsible for this patient’s current condition?", "answer": "Inhibition of 60S ribosomal subunit", "options": {"A": "ADP-ribosylation of elongation factor 2", "B": "Phospholipid degradation", "C": "Stimulation of guanylyl cyclase", "D": "ADP-ribosylation of a G protein", "E": "Inhibition of 60S ribosomal subunit"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 80-year-old woman seeks evaluation at an outpatient clinic for a firm nodular lump on the left side of her labia. The medical history is notable for hypertension, coronary artery disease status post CABG, and lichen sclerosus of the vagina that was treated with an over-the-counter steroid cream as needed. She first noticed the lump about 5 months ago. On physical examination, the temperature is 37°C (98.6°F), the blood pressure is 135/89 mm Hg, the pulse is 95/min, and the respiratory rate is 17/min. Examination of the genital area reveals a small nodular lump on the left labium majus with visible excoriations, but no white plaque-like lesions. What is the next best step in management?", "answer": "Vulvar punch biopsy", "options": {"A": "HPV DNA testing", "B": "Estrogen level measurement", "C": "Pap smear", "D": "Vulvar punch biopsy", "E": "Potassium hydroxide test after scraping of the lesion"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 75-year-old male is hospitalized for bloody diarrhea and abdominal pain after meals. Endoscopic work-up and CT scan lead the attending physician to diagnose ischemic colitis at the splenic flexure. Which of the following would most likely predispose this patient to ischemic colitis:", "answer": "Obstruction of the abdominal aorta following surgery", "options": {"A": "Increased splanchnic blood flow following a large meal", "B": "Essential hypertension", "C": "Obstruction of the abdominal aorta following surgery", "D": "Hyperreninemic hyperaldosteronism secondary to type II diabetes mellitus", "E": "Juxtaglomerular cell tumor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Two days following the home birth of her son, a mother brings the infant to the pediatric emergency room because of bilious vomiting. He is unable to pass meconium and his abdomen is distended. Endoscopic biopsy of the proximal colon demonstrates an absence of Meissner’s and Auerbach’s plexi in the bowel wall. Which of the following is the most likely diagnosis?", "answer": "Hirschsprung’s disease", "options": {"A": "Hirschsprung’s disease", "B": "Ileocecal intussusception", "C": "Meckel’s diverticulum", "D": "Juvenile polyposis syndrome", "E": "Volvulus of the sigmoid colon"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old man comes to the physician because of a 6-month history of increasing fatigue and reduced libido. He also complains of joint pain in both of his hands. His vital signs are within normal limits. Physical examination shows tanned skin and small testes. The second and third metacarpophalangeal joints of both hands are tender to palpation and range of motion is limited. The liver is palpated 2 to 3 cm below the right costal margin. Histopathologic examination of a liver biopsy specimen shows intracellular material that stains with Prussian blue. This patient is at greatest risk for developing which of the following complications?", "answer": "Restrictive cardiomyopathy", "options": {"A": "Colorectal carcinoma", "B": "Restrictive cardiomyopathy", "C": "Rheumatoid arthritis", "D": "Pancreatic adenocarcinoma", "E": "Non-Hodgkin lymphoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A general surgery intern is paged to the bedside of a 59-year-old male who underwent a successful sigmoidectomy for treatment of recurrent diverticulitis. The patient's nurse just recorded a temperature of 38.7 C, and relates that the patient is complaining of chills. The surgery was completed 8 hours ago and was complicated by extensive bleeding, with an estimated blood loss of 1,700 mL. Post-operative anemia was diagnosed after a hemoglobin of 5.9 g/dL was found; 2 units of packed red blood cells were ordered, and the transfusion was initiated 90 minutes ago. The patient's vital signs are as follows: T 38.7 C, HR 88, BP 138/77, RR 18, SpO2 98%. Physical examination does not show any abnormalities. After immediately stopping the transfusion, which of the following is the best management of this patient's condition?", "answer": "Monitor patient and administer acetaminophen", "options": {"A": "Hydrate with 1 L bolus of normal saline followed by maintenance fluids at 125 cc/hr", "B": "Monitor patient and administer acetaminophen", "C": "Prescribe diphenhydramine", "D": "Start supplemental oxygen by nasal cannula", "E": "Initiate broad spectrum antibiotics"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old man presents to the emergency department with anxiety. The patient states that he is very anxious and has not been able to take his home anxiety medications. He is requesting to have his home medications administered. The patient has a past medical history of anxiety and depression. His current medications include clonazepam, amitriptyline, and lorazepam. Notably, the patient has multiple psychiatric providers who currently care for him. His temperature is 99.2°F (37.3°C), blood pressure is 130/85 mmHg, pulse is 112/min, respirations are 22/min, and oxygen saturation is 100% on room air. Physical exam is notable for an anxious, sweating, and tremulous young man who becomes more confused during his stay in the emergency department. Which of the following should be given to this patient?", "answer": "Diazepam", "options": {"A": "Diazepam", "B": "Flumazenil", "C": "Midazolam", "D": "Sodium bicarbonate", "E": "Supportive therapy and monitoring"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 18-year-old female returning from a trip to a developing country presents with diarrhea and pain in the abdominal region. Microscopic evaluation of the stool reveals the presence of RBC's and WBC's. The patient reports poor sewage sanitation in the region she visited. The physician suspects a bacterial infection and culture reveals Gram-negative rods that are non-lactose fermenting. The A subunit of the bacteria's toxin acts to:", "answer": "Inhibit the 60S ribosome", "options": {"A": "Inhibit the 60S ribosome", "B": "Lyse red blood cells", "C": "Prevent phagocytosis", "D": "Inhibit exocytosis of ACh from synaptic terminals", "E": "ADP-ribosylate the Gs protein"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old man with a recent diagnosis of peptic ulcer disease currently treated with an oral proton pump inhibitor twice daily presents to the urgent care center complaining of acute abdominal pain which began suddenly less than 2 hours ago. On physical exam, you find his abdomen to be mildly distended, diffusely tender to palpation, and positive for rebound tenderness. Given the following options, what is the next best step in patient management?", "answer": "Urgent CT abdomen and pelvis", "options": {"A": "Abdominal radiographs", "B": "Urgent CT abdomen and pelvis", "C": "Upper endoscopy", "D": "H. pylori testing", "E": "Serum gastrin level"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 31-year-old male presents to the emergency room following an altercation with patrons at a local grocery store. He is acting aggressively toward hospital staff and appears to be speaking to non-existent individuals. On examination he is tachycardic and diaphoretic. Horizontal and vertical nystagmus is noted. The patient eventually admits to taking an illegal substance earlier in the evening. Which of the following mechanisms of action is most consistent with the substance this patient took?", "answer": "NMDA receptor antagonist", "options": {"A": "Adenosine antagonist", "B": "Biogenic amine reuptake inhibitor", "C": "Mu receptor agonist", "D": "GABA agonist", "E": "NMDA receptor antagonist"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old female presents to her primary care provider complaining of pain and stiffness in her hands and knees. She reports that the stiffness is worse in the morning and appears to get better throughout the day. She is otherwise healthy and denies any recent illness. She does not play sports. On examination, her metacarpal-phalangeal (MCP) and proximal interphalangeal (PIP) joints are swollen and erythematous. Her distal interphalangeal (DIP) joints appear normal. She exhibits pain with both passive and active range of motion in her knees bilaterally. Serological analysis reveals high titers of anti-cyclic citrullinated peptide antibodies. Which of the following processes underlies this patient’s condition?", "answer": "Synovial hypertrophy and pannus formation", "options": {"A": "Precipitation of monosodium urate crystals in the intra-articular space", "B": "Post-infectious inflammation of the articular surfaces", "C": "Aseptic necrosis of articular cartilage and subchondral bone", "D": "Degenerative deterioration of articular cartilage", "E": "Synovial hypertrophy and pannus formation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old man presents for severe abdominal pain and is diagnosed with appendicitis. He is taken for emergent appendectomy. During the procedure, the patient has massive and persistent bleeding requiring a blood transfusion. The preoperative laboratory studies showed a normal bleeding time, normal prothrombin time (PT), an INR of 1.0, and a normal platelet count. Postoperatively, when the patient is told about the complications during the surgery, he recalls that he forgot to mention that he has a family history of an unknown bleeding disorder. The postoperative laboratory tests reveal a prolonged partial thromboplastin time (PTT). Which of the following is the most likely diagnosis in this patient?", "answer": "Hemophilia A", "options": {"A": "Hemophilia A", "B": "Bernard-Soulier syndrome", "C": "Glanzman syndrome", "D": "Thrombotic thrombocytopenic purpura", "E": "von Willebrand disease"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 11-year-old girl is brought to the emergency department because of high-grade fever, headache, and nausea for 3 days. She avoids looking at any light source because this aggravates her headache. She has acute lymphoblastic leukemia and her last chemotherapy cycle was 2 weeks ago. She appears lethargic. Her temperature is 40.1°C (104.2°F), pulse is 131/min and blood pressure is 100/60 mm Hg. Examination shows a stiff neck. The pupils are equal and reactive to light. Neck flexion results in flexion of the knee and hip. Muscle strength is decreased in the right upper extremity. Deep tendon reflexes are 2+ bilaterally. Sensation is intact. Extraocular movements are normal. Two sets of blood cultures are obtained. Which of the following is the most appropriate next step in management?", "answer": "Antibiotic therapy", "options": {"A": "CT scan of the head", "B": "MRI of the brain", "C": "Antibiotic therapy", "D": "Lumbar puncture", "E": "Acyclovir therapy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 49-year-old man presents to a new primary care provider complaining of fatigue and occasional fever over the last month. These symptoms are starting to affect his job and he would like treatment. The physician runs a standard metabolic panel that shows elevated AST and ALT. The patient is then tested for hepatitis viruses. He is hepatitis C positive. The patient and his doctor discuss treatment options and agree upon pegylated interferon and oral ribavirin. Which side-effect is most likely while taking the ribavirin?", "answer": "Hemolytic anemia", "options": {"A": "Hemolytic anemia", "B": "Drug-associated lupus", "C": "Leukopenia", "D": "Hyperthyroidism", "E": "Rash"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old immigrant presents with unintentional weight loss, sleep hyperhidrosis, and a persistent cough. He says these symptoms have been present for quite some time. Upon imaging, many granulomas in the upper lobes are present. It is noted that these apical granulomas have centers of necrosis that appear cheese-like in appearance. Encircling the area of necrosis are large cells with cytoplasms pale in color. Of the following surface markers, which one is specific for these cells?", "answer": "CD14", "options": {"A": "CD8", "B": "CD4", "C": "CD3", "D": "CD14", "E": "CD20"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman comes to the emergency room because of fever and severe left knee pain for the past week. She has not sustained any trauma or injury to the area, nor has she traveled or taken part in outdoor activities in the recent past. She is sexually active with one male partner, and they use condoms inconsistently. She appears ill. Her temperature is 38°C (100.4°F), pulse is 98/min, respirations are 17/min, and blood pressure is 106/72 mm Hg. Physical examination shows multiple painless pustular lesions on her ankles and the dorsum and soles of her feet bilaterally, as well as a swollen, erythematous, exquisitely tender left knee. Her wrists are also mildly edematous and tender, with pain on extension. X-ray of the knees shows tissue swelling. Arthrocentesis of the knee shows yellow purulent fluid. Gram stain is negative. Analysis of the synovial fluid shows a leukocyte count of 58,000/mm3 with 93% neutrophils and no crystals. Which of the following is the most appropriate pharmacotherapy?", "answer": "Intramuscular ceftriaxone and oral azithromycin", "options": {"A": "Oral penicillin V", "B": "Oral hydroxychloroquine", "C": "Intramuscular ceftriaxone and oral azithromycin", "D": "Oral doxycycline", "E": "Intramuscular ceftriaxone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old man presents with restlessness and an inability to sit or lie down for the past 2 days. Past medical history is significant for schizophrenia, diagnosed 3 weeks ago and managed medically. Vital signs are a blood pressure of 140/90 mm Hg and a pulse of 96/min. On physical examination, the patient is fidgety and anxious but well-oriented. Which of the following is the most likely diagnosis in this patient?", "answer": "Akathisia", "options": {"A": "Psychotic agitation", "B": "Essential tremor", "C": "Acute muscular dystonia", "D": "Drug-induced parkinsonism", "E": "Akathisia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "In a previous experiment infecting hepatocytes, it was shown that viable HDV virions were only produced in the presence of a co-infection with HBV. To better understand which HBV particle was necessary for the production of viable HDV virions, the scientist encoded in separate plasmids the various antigens/proteins of HBV and co-infected the hepatocytes with HDV. In which of the experiments would viable HDV virions be produced in conjunction with the appropriate HBV antigen/protein?", "answer": "HBsAg", "options": {"A": "HBsAg", "B": "HBV DNA polymerase", "C": "HBcAg", "D": "HBV RNA polymerase", "E": "HBeAg"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 61-year-old woman presents to her primary care physician for a routine check-up. Physical examination demonstrates asymmetric peripheral neuropathy in her feet. The patient has no previous relevant history and denies any symptoms of diabetes. Routine blood work shows normal results, and she is referred to a hematologist. Subsequent serum protein electrophoresis demonstrates a slightly elevated gamma globulin level, and monoclonal gammopathy of undetermined significance is diagnosed. Which of the following diseases is most likely to develop over the course of this patient’s condition?", "answer": "Multiple myeloma", "options": {"A": "Waldenström macroglobulinemia", "B": "Multiple myeloma", "C": "Acute myelocytic leukemia", "D": "Chronic lymphocytic leukemia", "E": "Chronic myelocytic leukemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 71-year-old man presents to his primary care physician because he is increasingly troubled by a tremor in his hands. He says that the tremor is worse when he is resting and gets better when he reaches for objects. His wife reports that he has been slowing in his movements and also has difficulty starting to walk. His steps have been short and unsteady even when he is able to initiate movement. Physical exam reveals rigidity in his muscles when tested for active range of motion. Histology in this patient would most likely reveal which of the following findings?", "answer": "Alpha-synuclein", "options": {"A": "Alpha-synuclein", "B": "Intracellular hyperphosphorylated tau", "C": "Hyperphosphorylated tau inclusion bodies", "D": "Large intracellular vacuoles", "E": "Perivascular inflammation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old man is brought to the emergency department while on vacation with a history of sudden onset vertigo and difficulty walking. He was in normal health since starting his vacation a week ago, but today he is suffering from a loss of balance, mild headache, and has had 5–6 episodes of vomiting over the last few hours. He denies fever, neck pain, head trauma, weakness, and diplopia. Past medical history is significant for hypertension and dyslipidemia. His medications include valsartan and atorvastatin, but he missed several doses since leaving for this trip. Blood pressure is 198/112 mm Hg, the heart rate is 76/min, the respiratory rate is 16/min, and the temperature is 37.0°C (98.6°F). The patient is awake and oriented to time, place, and person. Extraocular movements are within normal limits. Muscle strength is normal in all 4 extremities. An urgent head CT is ordered and shown in the picture. What additional clinical features be expected in this patient?", "answer": "Inability to perform repetitive alternating movements", "options": {"A": "Inability to comprehend commands", "B": "Inability to perform repetitive alternating movements", "C": "Inability to speak fluently", "D": "Right-sided neglect", "E": "Right-sided visual field loss"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old man presents with painless swelling of the neck over the past week. He also has noted severe night sweats, which require a change of clothes and bed linens the next day. His medical history is significant for long-standing hypertension. He received a kidney transplant 6 years ago. His current medications include amlodipine, metoprolol, furosemide, aspirin, tacrolimus, and mycophenolate. His family history is significant for his sister, who died last year from lymphoma. A review of systems is positive for a 6-kg (13.2-lb) unintentional weight loss over the past 2 months. His vital signs include: temperature 37.8℃ (100.0℉) and blood pressure 120/75 mm Hg. On physical examination, there are multiple painless lymph nodes, averaging 2 cm in diameter, palpable in the anterior and posterior triangles of the neck bilaterally. Axillary and inguinal lymphadenopathy is palpated on the right side. Abdominal examination is significant for a spleen of 16 cm below the cost margin on percussion. Laboratory studies are significant for the following:\nHemoglobin 9 g/dL\nMean corpuscular volume 88 μm3\nLeukocyte count 12,000/mm3\nPlatelet count 130,000/mm3\nCreatinine 1.1 mg/dL\nLactate dehydrogenase (LDH) 1 000 U/L\nA peripheral blood smear is unremarkable. Which of the following is the most likely diagnosis in this patient?", "answer": "Non-Hodgkin’s lymphoma (NHL)", "options": {"A": "Chronic lymphocytic leukemia (CLL)", "B": "Drug-induced lymphadenopathy", "C": "Cytomegalovirus infection", "D": "Multiple myeloma", "E": "Non-Hodgkin’s lymphoma (NHL)"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old man is brought to the emergency department by his neighbor 2 hours after ingesting an unknown substance in a suicide attempt. He is confused and unable to provide further history. His temperature is 39.1°C (102.3°F), pulse is 124/min, respiratory rate is 12/min, and blood pressure is 150/92 mm Hg. His skin is dry. Pupils are 12 mm and minimally reactive. An ECG shows no abnormalities. Which of the following is the most appropriate treatment for this patient's condition?", "answer": "Physostigmine", "options": {"A": "Sodium bicarbonate", "B": "Physostigmine", "C": "N-acetylcysteine", "D": "Glucagon", "E": "Flumazenil"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 81-year-old man presents to his primary care physician for his yearly exam. His past medical history is significant for osteopenia, nephrolithiasis, and hypertension. His family history is significant for relatives who had early onset kidney failure. He takes occasional acetaminophen and supplemental calcium/vitamin D. He is physically active with a normal body mass index (BMI) and has no current concerns. Review of his laboratory results today were compared with those from 15 years ago with the following findings:\n\nResults today:\nSerum creatinine concentration: 1.1 mg/dL\nUrine creatinine concentration: 100 mg/dL\nUrine volume: 1000 mL/day\n\nResults 15 years ago:\nSerum creatinine concentration: 1.1 mg/dL\nUrine creatinine concentration: 120 mg/dL\nUrine volume: 1000 mL/day\n\nWhich is the most likely cause of these changes in his creatinine clearance?", "answer": "Normal aging", "options": {"A": "Benign prostatic hyperplasia", "B": "Nephrolithiasis", "C": "Normal aging", "D": "Polycystic kidney disease", "E": "Renovascular disease"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old man presents to his primary care provider complaining of fatigue, mild headache, and discomfort with chewing for roughly 1 week. Before this, he felt well overall, but now is he is quite bothered by these symptoms. His medical history is notable for hypertension and hyperlipidemia, both controlled. On examination, he is uncomfortable but nontoxic-appearing. There is mild tenderness to palpation over his right temporal artery, but otherwise the exam is not revealing. Prompt recognition and treatment can prevent which of the following feared complications:", "answer": "Blindness", "options": {"A": "Renal failure", "B": "Blindness", "C": "Pericarditis", "D": "Pulmonary fibrosis", "E": "Cognitive impairment"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 14-month-old boy is brought to the clinic for evaluation of a rash. The rash started on the face and spread to the trunk. He also had a fever and cough for the past 2 days. His mother says that they recently immigrated from Asia and cannot provide vaccination records. The physical examination reveals a maculopapular rash on the face, trunk, and proximal limbs with no lymphadenopathy. Blue-white spots are noted on the oral mucosa and there is bilateral mild conjunctival injection. The causative agent of this condition belongs to which of the following virus families?", "answer": "ssRNA enveloped viruses", "options": {"A": "ssDNA enveloped viruses", "B": "dsRNA enveloped viruses", "C": "ssRNA naked viruses", "D": "dsRNA naked viruses", "E": "ssRNA enveloped viruses"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old G1P0 woman at 26 weeks gestation presents to the clinic for evaluation of an abnormal glucose tolerance test. She denies any symptoms, but states that she was given 50 g of oral glucose 1 week earlier and demonstrated a subsequent venous plasma glucose level of 156 mg/dL 1 hour later. The vital signs are: blood pressure, 112/78 mm Hg; pulse, 81/min; and respiratory rate, 16/min. Physical examination is within normal limits. Which of the following is the most appropriate next step in management?", "answer": "Administer an oral, 3-hour 100 g glucose dose", "options": {"A": "Repeat the 50 g oral glucose challenge", "B": "Administer an oral, 3-hour 100 g glucose dose", "C": "Advise the patient to follow an American Diabetic Association diet plan", "D": "Begin insulin treatment", "E": "Order a fetal ultrasound examination"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A newborn of a mother with poor antenatal care is found to have a larger than normal head circumference with bulging fontanelles. Physical examination reveals a predominant downward gaze with marked eyelid retraction and convergence-retraction nystagmus. Ultrasound examination showed dilated lateral ventricles and a dilated third ventricle. Further imaging studies reveal a solid mass in the pineal region. Which of the following is the most likely finding for this patient?", "answer": "Compression of periaqueductal grey matter", "options": {"A": "Normal lumbar puncture opening pressure", "B": "Stenotic intraventricular foramina", "C": "Dilated cisterna magna", "D": "Compression of periaqueductal grey matter", "E": "Hypertrophic arachnoid granulations"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old man comes to the physician because of a progressive swelling and pain in his right ring finger for the past 2 days. The pain began while playing football, when his finger got caught in the jersey of another player who forcefully pulled away. Examination shows that the right ring finger is extended. There is pain and swelling at the distal interphalangeal joint. When the patient is asked to make a fist, his right ring finger does not flex at the distal interphalangeal joint. There is no joint laxity. Which of the following is the most likely diagnosis?", "answer": "Rupture of the flexor digitorum profundus tendon at its point of insertion", "options": {"A": "Rupture of the flexor digitorum profundus tendon at its point of insertion", "B": "Closed fracture of the distal phalanx", "C": "Rupture of the extensor digitorum tendon at its point of insertion", "D": "Inflammation of the flexor digitorum profundus tendon sheath", "E": "Slipping of the central band of the extensor digitorum tendon"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 50-year-old man comes to the physician for a routine checkup. He has had a progressively increasing swelling on the nape of his neck for 2 months. He does not have a fever or any discharge from the swelling. He underwent a colectomy for colon cancer at the age of 43 years. He has type 2 diabetes mellitus, hypertension, and osteoarthritis of the left knee. Current medications include insulin glargine, metformin, enalapril, and naproxen. He has worked as a traffic warden for the past 6 years and frequently plays golf. He appears healthy. His temperature is 37.3°C (99.1°F), pulse is 88/min, and blood pressure is 130/86 mm Hg. Examination of the neck shows a 2.5-cm (1-in) firm, mobile, and painless nodule. The skin over the nodule cannot be pinched. The lungs are clear to auscultation. The remainder of the examination shows no abnormalities. A photograph of the lesion is shown. Which of the following is the most likely diagnosis?", "answer": "Epidermoid cyst", "options": {"A": "Actinic keratosis", "B": "Epidermoid cyst", "C": "Dermatofibroma", "D": "Lipoma", "E": "Squamous cell carcinoma\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 67-year-old man comes to the physician because of a 3-day history of fever, chills, headache, and fatigue. He appears ill. His temperature is 39°C (102.2°F). Analysis of nasal secretions shows infection with an enveloped, single-stranded segmented RNA virus. In response to infection with this pathogen, certain cells present antigens from the pathogen to CD8+ T-lymphocytes. Which of the following statements about the molecules used for the presentation of these antigens is most accurate?", "answer": "The molecule consists of a heavy chain associated with β2 microglobulin", "options": {"A": "The antigens are loaded onto the molecule within lysosomes", "B": "The molecule consists of a heavy chain associated with β2 microglobulin", "C": "The molecule is made up of 2 chains of equal length", "D": "The molecule is selectively expressed by antigen-presenting cells", "E": "The molecule is a product of the HLA-DP, HLA-DQ, and -DR genes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old female, being treated on the medical floor for community-acquired pneumonia with levofloxacin, develops watery diarrhea. She reports at least 9 episodes of diarrhea within the last two days, with lower abdominal discomfort and cramping. Her temperature is 98.6° F (37° C), respiratory rate is 15/min, pulse is 67/min, and blood pressure is 122/98 mm Hg. Her physical examination is unremarkable. Laboratory testing shows:\nHb%   13 gm/dL\nTotal count (WBC):   13,400/mm3\nDifferential count:    \n  Neutrophils: 80%\n  Lymphocytes: 15%\n  Monocytes: 5%\nESR:   33 mm/hr\nWhat is the most likely diagnosis?", "answer": "C. difficile colitis", "options": {"A": "Ulcerative colitis", "B": "C. difficile colitis", "C": "Irritable bowel syndrome", "D": "Osmotic diarrhea", "E": "Giardiasis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 7-year-old girl presents to her primary care physician for a routine check-up. The physician allows the medical student to perform a physical examination. The medical student notes hearing impairment as well as the findings show in Figures A and B. Radiographs show indications of multiple old fractures of the humerus that have healed. After questioning the girl’s parents, the medical student learns that in addition, the patient is extremely picky with her food and eats a diet consisting mainly of cereal and pasta. What is the most likely etiology of the patient’s disease?", "answer": "Deficiency of type 1 collagen", "options": {"A": "Decreased bone mineral density", "B": "Defective mineralization of cartilage", "C": "Deficiency of type 1 collagen", "D": "Dietary deficiency of ascorbic acid", "E": "Non-accidental trauma"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 47-year-old man comes to the physician because of abdominal pain and foul-smelling, watery diarrhea for several days. He has not had nausea, vomiting, or blood in the stool. He has a history of alcohol use disorder and recently completed a 7-day course of clindamycin for pneumonia. He has not traveled out of the United States. Which of the following toxins is most likely to be involved in the pathogenesis of this patient's symptoms?", "answer": "Clostridioides difficile cytotoxin", "options": {"A": "Shiga toxin", "B": "Cholera toxin", "C": "Cereulide toxin", "D": "Clostridioides difficile cytotoxin", "E": "Alpha toxin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 6-year-old boy presents to the clinic because of monosymptomatic enuresis for the past month. Urinalysis, detailed patient history, and fluid intake, stool, and voiding diary from a previous visit all show no abnormalities. The parent and child are referred for education and behavioral therapy. Enuresis decreases but persists. Both the patient and his mother express concern and want this issue to resolve as soon as possible. Which of the following is the most appropriate next step in management?", "answer": "Enuresis alarm", "options": {"A": "Behavioral therapy", "B": "DDAVP", "C": "Enuresis alarm", "D": "Oxybutynin", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old homeless woman is brought to the emergency department by ambulance 30 minutes after the police found her on the sidewalk. On arrival, she is unresponsive. Her pulse is 76/min, respirations are 6/min, and blood pressure is 110/78 mm Hg. Examination shows cool, dry skin. The pupils are pinpoint and react sluggishly to light. Intravenous administration of a drug is initiated. Two minutes after treatment is started, the patient regains consciousness and her respirations increase to 12/min. The drug that was administered has the strongest effect on which of the following receptors?", "answer": "μ-receptor", "options": {"A": "M1 receptor", "B": "Ryanodine receptor", "C": "μ-receptor", "D": "GABAA receptor", "E": "5-HT2A receptor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An infectious disease investigator is evaluating the diagnostic accuracy of a new interferon-gamma-based assay for diagnosing tuberculosis in patients who have previously received a Bacillus Calmette-Guérin (BCG) vaccine. Consenting participants with a history of BCG vaccination received an interferon-gamma assay and were subsequently evaluated for tuberculosis by sputum culture. Results of the study are summarized in the table below.\nTuberculosis, confirmed by culture No tuberculosis Total\nPositive interferon-gamma assay 90 6 96\nNegative interferon-gamma assay 10 194 204\nTotal 100 200 300\nBased on these results, what is the sensitivity of the interferon-gamma-based assay for the diagnosis of tuberculosis in this study?\"", "answer": "90/100", "options": {"A": "194/200", "B": "90/100", "C": "90/96", "D": "100/300", "E": "194/204"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Several patients at a local US hospital present with chronic secretory diarrhea. Although there are multiple potential causes of diarrhea present in these patients, which of the following is most likely the common cause of their chronic secretory diarrhea?", "answer": "Medications", "options": {"A": "Lymphocytic colitis", "B": "Medications", "C": "Lactose intolerance", "D": "Carcinoid tumor", "E": "Crohn’s disease with ileitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old woman with sickle cell disease and at 39-weeks' gestation is brought to the emergency department in active labor. She has had multiple episodes of acute chest syndrome and has required several transfusions in the past. She has a prolonged vaginal delivery complicated by postpartum bleeding, and she receives a transfusion of 1 unit of packed red blood cells. One hour later, the patient experiences acute flank pain. Her temperature is 38.7°C (101.6°F), pulse is 115/min, respirations are 24/min, and blood pressure is 95/55 mm Hg. Foley catheter shows dark brown urine. Further evaluation of this patient is most likely to show which of the following?", "answer": "Positive direct Coombs test", "options": {"A": "Bilateral pulmonary infiltrates on chest x-ray", "B": "Serum antibodies against class I HLA antigens", "C": "Positive direct Coombs test", "D": "Positive blood cultures", "E": "Low levels of serum IgA immunoglobulins"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old man is brought by his mother to his pediatrician in order to complete medical clearance forms prior to attending college. During the visit, his mother asks about what health risks he should be aware of in college. Specifically, she recently saw on the news that some college students were killed by a fatal car crash. She therefore asks about causes of death in this population. Which of the following is true about the causes of death in college age individuals?", "answer": "More of them die from homicide than cancer", "options": {"A": "More of them die from suicide than injuries", "B": "More of them die from homicide than injuries", "C": "More of them die from homicide than suicide", "D": "More of them die from cancer than suicide", "E": "More of them die from homicide than cancer"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 7-month old boy, born to immigrant parents from Greece, presents to the hospital with pallor and abdominal distention. His parents note that they recently moved into an old apartment building and have been concerned about their son's exposure to chipped paint from the walls. On physical exam, the patient is found to have hepatosplenomegaly and frontal skull bossing. Hemoglobin electrophoresis reveals markedly increased HbF and HbA2 levels. What would be the most likely findings on a peripheral blood smear?", "answer": "Microcytosis and hypochromasia of erythrocytes", "options": {"A": "Basophilic stippling of erythrocytes", "B": "Macrocytosis of erythrocytes with hypersegmented neutrophils", "C": "Microcytosis and hypochromasia of erythrocytes", "D": "Schistocytes and normocytic erythrocytes", "E": "Sickling of erythrocytes"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old woman comes to the physician because of progressively worsening lower back pain. The pain radiates down the right leg to the lateral side of the foot. She has had no trauma, urinary incontinence, or fever. An MRI of the lumbar spine shows disc degeneration and herniation at the level of L5–S1. Which of the following is the most likely finding on physical examination?", "answer": "Weak achilles tendon reflex", "options": {"A": "Difficulty walking on heels", "B": "Exaggerated patellar tendon reflex", "C": "Diminished sensation of the anus and genitalia", "D": "Weak achilles tendon reflex", "E": "Diminished sensation of the anterior lateral thigh\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old woman comes to the physician because of a 4-month history of progressive pain and stiffness of the fingers of her right hand that is worse at the end of the day. She works as a hair dresser and has to take frequent breaks to rest her hand. She has hypertension, for which she takes hydrochlorothiazide. Two weeks ago, she completed a course of oral antibiotics for a urinary tract infection. Her sister has systemic lupus erythematosus. She drinks one to two beers daily and occasionally more on weekends. Over the past 2 weeks, she has been taking ibuprofen as needed for the joint pain. Her vital signs are within normal limits. Physical examination shows swelling, joint-line tenderness, and decreased range of motion of the right first metacarpophalangeal joint as well as the 2nd and 4th distal interphalangeal joints of the right hand. Discrete, hard, mildly tender swellings are palpated over the 2nd and 4th distal interphalangeal joints of the right hand. Which of the following is the most likely underlying mechanism for these findings?", "answer": "Degenerative disease of the joints", "options": {"A": "Monosodium urate crystal precipitation in the joints", "B": "Bacterial infection of the joint space", "C": "Autoimmune-mediated cartilage erosion", "D": "Degenerative disease of the joints", "E": "Calcium pyrophosphate dihydrate crystal precipitation in the joints"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 51-year-old man presents to his dermatologist because of severe stomatitis and superficial skin erosions over his trunk. His condition started 2 months ago and was unresponsive to oral antibiotics and antiherpetic medications. He has no history of a similar rash. His medical history is remarkable for type 2 diabetes mellitus and essential hypertension. The physical examination reveals numerous flaccid blisters and bullae which rupture easily. Nikolsky's sign is positive. Which of the following best represents the etiology of this patient’s condition?", "answer": "Anti-desmoglein-3 antibodies", "options": {"A": "Anti-hemidesmosome antibodies", "B": "Increased mitotic activity of basal and suprabasal cells", "C": "Cutaneous T cell lymphoma", "D": "Anti-desmoglein-3 antibodies", "E": "Dermatophyte infection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old male presents to his primary care physician for a routine check-up. He reports that he is doing well overall without any bothersome symptoms. His past medical history is significant only for hypertension, which has been well controlled with losartan. Vital signs are as follows: T 37.0 C, HR 80, BP 128/76, RR 14, SpO2 99%. Physical examination does not reveal any concerning abnormalities. The physician recommends a fecal occult blood test at this visit to screen for the presence of any blood in the patient's stool that might be suggestive of an underlying colorectal cancer. Which of the following best describes this method of disease prevention?", "answer": "Secondary prevention", "options": {"A": "Primordial prevention", "B": "Primary prevention", "C": "Secondary prevention", "D": "Tertiary prevention", "E": "Quaternary prevention"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man presents to the emergency department because of pain in the center of his chest that is radiating down his left arm and up the left side of his neck. The pain started suddenly 30 minutes ago while the patient was at work. The patient describes the pain as squeezing in nature, 10/10 in intensity, and is associated with nausea and difficulty breathing. He has had type 2 diabetes mellitus for 15 years, hypertension for 10 years, and dyslipidemia, but he denies any history of a cardiac problem. He has a 40-pack-year history of smoking but does not drink alcohol. Vital signs include: blood pressure 80/40 mm Hg, regular pulse 90/min, and temperature 37.2°C (98.9°F). Chest auscultation reveals diffuse bilateral rales with no murmurs. ECG reveals convex ST-segment elevation in leads V1 to V6 and echocardiogram shows anterolateral hypokinesis, retrograde blood flow into the left atrium, and an ejection fraction of 45%. Which of the following best describe the mechanism of this patient’s illness?", "answer": "Occlusion of the left anterior descending artery with rupture of a papillary muscle", "options": {"A": "Occlusion of the right coronary artery, with infarction of the conduction system", "B": "Occlusion of the left anterior descending artery with rupture of a papillary muscle", "C": "Occlusion of the left anterior descending artery with interventricular septal rupture", "D": "Ventricular free wall rupture", "E": "Mitral leaflet thickening and fibrosis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 29-year-old African American female presents to your office with extreme fatigue and bilateral joint pain. Serologies demonstrate the presence of rheumatoid factor along with anti-Smith and anti-dsDNA antibodies. A VDRL syphilis test is positive. You order a coagulation profile, which reveals normal bleeding time, normal PT, and prolonged PTT as well as normal platelet count. Further evaluation is most likely to reveal which of the following?", "answer": "History of multiple spontaneous abortions", "options": {"A": "Palmar rash", "B": "HLA-B27 positivity", "C": "Factor VIII deficiency", "D": "History of multiple spontaneous abortions", "E": "Immune thrombocytopenia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old man comes to the physician because of a 5-day history of fever, chills, and dyspnea. His temperature is 38.9°C (102°F) and pulse is 90/min. Cardiac examination shows a murmur. In addition to other measures, cardiac catheterization is performed. A graph showing the results of the catheterization is shown. This patient most likely has which of the following valvular heart defects?", "answer": "Aortic regurgitation", "options": {"A": "Mitral stenosis", "B": "Mitral regurgitation", "C": "Pulmonary regurgitation", "D": "Aortic regurgitation", "E": "Aortic stenosis\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 54-year-old woman comes to the physician because of a painful skin lesion on her right leg for 1 month. It initially started out as a small red spot but has rapidly increased in size during this period. She remembers an ant bite on her leg prior to the lesion occurring. She was treated for anterior uveitis 8 months ago with corticosteroids. She has Crohn's disease, type 2 diabetes mellitus, and hypertension. Current medications include insulin, mesalamine, enalapril, and aspirin. She returned from Wisconsin after visiting her son 2 months ago. Her temperature is 37.6°C (98°F), pulse is 98/min, and blood pressure is 126/88 mm Hg. Examination shows pitting pedal edema of the lower extremities. There is a 4-cm tender ulcerative lesion on the anterior right leg with a central necrotic base and purplish irregular borders. There are dilated tortuous veins in both lower legs. Femoral and pedal pulses are palpated bilaterally. Which of the following is the most likely diagnosis?", "answer": "Pyoderma gangrenosum", "options": {"A": "Ecthyma gangrenosum", "B": "Pyoderma gangrenosum", "C": "Blastomycosis", "D": "Squamous cell carcinoma", "E": "Basal cell carcinoma\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A primary care physician is recently receiving more negative online reviews from his patients. He is increasingly feeling tired and has written 2 wrong prescriptions over the past month alone. Currently, on his panel, he has a list of 1,051 patients, half of whom are geriatric patients. He spends approx. 51 hours per week visiting about 20 patients a day. He has no history of a serious illness and takes no medications. An evaluation by a psychiatrist shows no primary psychiatric disorders. According to recent national surveys, which of the following do physicians more frequently recognize as a contributor to this physician’s current condition?", "answer": "Excessive bureaucratic tasks", "options": {"A": "The number of patients on his panel", "B": "Excessive bureaucratic tasks", "C": "Working too many hours", "D": "Concern over online reputation", "E": "The number of geriatric patients on his panel"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old Caucasian woman is enrolled in a randomized controlled trial to study cardiac function in the setting of several different drugs. She is started on verapamil and instructed to exercise at 50% of her VO2 max while several cardiac parameters are being measured. During this experiment, which of the following represents the relative conduction speed through the heart from fastest to slowest?", "answer": "Purkinje fibers > atria > ventricles > AV node", "options": {"A": "Atria > Purkinje fibers > ventricles > AV node", "B": "AV node > ventricles > atria > Purkinje fibers", "C": "Purkinje fibers > ventricles > atria > AV node", "D": "Purkinje fibers > atria > ventricles > AV node", "E": "Purkinje fibers > AV node > ventricles > atria"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy comes to the physician because of a generalized rash for 3 days. Over the past 5 days, he has also had a high fever and a sore throat. His 16-year-old sister was treated for infectious mononucleosis 2 weeks ago. He returned from a summer camp a week ago. His immunizations are up-to-date. Three years ago, he required intubation after an allergic reaction to dicloxacillin. The patient appears ill. His temperature is 38.2°C (100.8°F). Examination shows circumferential oral pallor. Cervical lymphadenopathy is present. There is tonsillar erythema and exudate. A confluent, blanching, punctate erythematous rash with a rough texture is spread over his trunk and extremities. His hemoglobin concentration is 13.3 g/dL, leukocyte count is 12,000/mm3, and erythrocyte sedimentation rate is 43 mm/h. Which of the following is the most appropriate next step in management?", "answer": "Azithromycin therapy", "options": {"A": "Acyclovir therapy", "B": "Doxycycline therapy", "C": "Amoxicillin therapy", "D": "Azithromycin therapy", "E": "Cephalexin therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old woman comes to the physician because of a swelling on her neck for 5 months. It has gradually enlarged in size and is mildly painful. She has also had intermittent episodes of throbbing headache, sweating, and palpitations over the past 3 months. Menses occur at regular 28-day intervals and last for 4–5 days. She does not smoke, occasionally consumes alcohol on weekends. She appears thin and pale. Her temperature is 38.7°C (101.7°F), pulse is 112/min, and blood pressure is 140/90 mm Hg. Examination shows a firm, 3-cm swelling on the neck that moves with swallowing; there is no lymphadenopathy. Cardiopulmonary examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13 g/dL\nLeukocyte count 9500/mm3\nPlatelet count 230,000/mm3\nSerum\nNa+ 136 mEq/L\nK+ 3.5 mEq/L\nCl- 104 mEq/L\nTSH 2.3 μU/mL\nCalcitonin 300 ng/dL (Normal < 5 ng/dL)\nAn electrocardiogram shows sinus tachycardia. Which of the following laboratory abnormalities is most likely to be seen?\"", "answer": "Increased plasma metanephrines", "options": {"A": "Increased serum gastrin", "B": "Increased serum cortisol", "C": "Increased urinary 5-HIAA", "D": "Increased serum T3 levels", "E": "Increased plasma metanephrines"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 31-year-old G3P1 woman who is at 37 weeks of gestation is brought into the emergency department by her husband after repeated twitching. According to the husband, they were watching TV when she suddenly became unresponsive and her hands and legs started shaking. The episode lasted about 5 minutes and she “seemed to be sleeping afterwards.” Her past medical history is significant for pregnancy induced hypertension. The patient is tired but responsive and denies urinary incontinence, paresthesia, fever, upper respiratory signs, or new medication changes. She denies a history of seizures. Her temperature is 99°F (37°C), blood pressure is 186/97 mmHg, pulse is 96/min, and respirations are 12/min. Physical examination demonstrates a lethargic patient with moderate right upper quadrant tenderness. What is the most appropriate next step for this patient?", "answer": "Intravenous magnesium sulfate", "options": {"A": "Emergency cesarean section", "B": "Expectant management", "C": "Intravenous ampicillin and gentamicin", "D": "Intravenous infusion of oxytocin", "E": "Intravenous magnesium sulfate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man was picked up by the security personnel for voiding urine and defecating at an inappropriate place in the community. On questioning, he was making offensive remarks and behaving inappropriately. On physical examination, the physician observed an ataxic gait and amnesia. Initial urine drug screen is negative for any drugs of abuse. Which is the most likely pathological finding present in this patient?", "answer": "Pick bodies", "options": {"A": "Drug abuse", "B": "PrPSC Sheets", "C": "Lewy bodies", "D": "Pick bodies", "E": "Amyloid plaques"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old man undergoes an exercise stress test for a 1-week history of squeezing substernal chest pain that is aggravated by exercise and relieved by rest. During the test, there is a substantial increase in the breakdown of glycogen in the muscle cells. Which of the following changes best explains this intracellular finding?", "answer": "Activation of phosphorylase kinase", "options": {"A": "Decrease in protein kinase A", "B": "Activation of phosphorylase kinase", "C": "Increase in glucose-6-phosphate", "D": "Activation of protein phosphatase", "E": "Inactivation of glycogen synthase kinase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old man presents to the general practitioner with a skin rash that has been present for 2 days. The rash appeared suddenly and has progressively gotten worse. It started off as an erythematous lesion on the back of his hands and also over his nose. The lesions over his hands have become bullous and tense. He has never experienced similar symptoms before. He just got back from a canoeing trip during a very hot and sunny weekend. Physical exam is significant for erythematous, vesicular lesions over the nape of the neck and bridge of the nose as well as tense bullae over the dorsum of both hands. The attending physician suspects a defect in the synthesis of heme and orders some blood tests. Which of the following precursors will most likely be elevated in this patient?", "answer": "Uroporphyrinogen III", "options": {"A": "Uroporphyrinogen III", "B": "Hydroxymethylbilane", "C": "Porphobilinogen", "D": "δ-Aminolevulinic acid", "E": "Protoporphyrin IX"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman, gravida 2, para 1, at 38 weeks' gestation comes to the emergency department because of vaginal bleeding for the past hour. The patient reports that she felt contractions prior to the onset of the bleeding, but the contractions stopped after the bleeding started. She also has severe abdominal pain. Her first child was delivered by lower segment transverse cesarean section because of a nonreassuring fetal heart rate. Her pulse is 110/min, respirations are 17/min, and blood pressure is 90/60 mm Hg. Examination shows diffuse abdominal tenderness with no rebound or guarding; no contractions are felt. The fetal heart rate shows recurrent variable decelerations. Which of the following is the most likely diagnosis?", "answer": "Uterine rupture", "options": {"A": "Abruptio placentae", "B": "Vasa previa", "C": "Uterine rupture", "D": "Uterine inertia", "E": "Amniotic fluid embolism"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to the emergency department by his parents for difficulty breathing. He was playing outside in the snow and had progressive onset of wheezing and gasping. His history is notable for eczema and nut allergies. The patient has respirations of 22/min and is leaning forward with his hands on his legs as he is seated on the table. Physical examination is notable for inspiratory and expiratory wheezes on exam. A nebulized medication is started and begins to relieve his breathing difficulties. Which of the following is increased in this patient as a result of this medication?", "answer": "Cyclic AMP", "options": {"A": "Diacylglycerol", "B": "Cyclic GMP", "C": "Cyclic AMP", "D": "Protein kinase C", "E": "ATP"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 78-year-old male with history of coronary artery disease, status post coronary stent placement currently on aspirin and clopidogrel was found down in his bathroom by his wife. His GCS score was 3 and an accurate physical exam is limited. A stat non-contrast CT scan of his brain demonstrated a large right parietal intracranial hemorrhage with surrounding edema. He was promptly transferred to the intensive care unit (ICU) for monitoring. Over the next day, his mental status continues to worsen but repeat CT scan shows no new bleeding. In addition, the patient’s urinary output has been >200 cc/hr over the last several hours and increasing. His temperature is 99.0 deg F (37.2 deg C), blood pressure is 125/72 mmHg, pulse is 87/min, and respirations are 13/min. Which of the following values would most likely correspond to the patient’s urine specific gravity, urine osmolality, plasma osmolality, and serum sodium?", "answer": "Low, Low, High, High", "options": {"A": "High, High, Low, Low", "B": "Low, High, High, High", "C": "Low, Low, High, Low", "D": "Low, Low, High, High", "E": "High, Low, Low, High"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old woman comes to the physician for a follow-up examination. One month ago, she was diagnosed with carcinoma of the left breast. She underwent a lumpectomy for a 2.1-cm mass and sentinel lymph node biopsy 2 weeks ago. The biopsy of the breast mass showed margin-free invasive ductal carcinoma; immunohistochemistry showed the carcinoma is estrogen-receptor and progesterone-receptor negative, and HER2-receptor positive. The lymph node biopsy was negative for metastases. Examination shows a healing surgical incision over the left breast. There is no palpable axillary lymphadenopathy. Her physician decides to initiate treatment with appropriate pharmacotherapy. Which of the following is the most appropriate next step in management?", "answer": "Echocardiography", "options": {"A": "Echocardiography", "B": "Fundoscopy", "C": "Dual energy x-ray absorptiometry scan", "D": "X-ray of the chest", "E": "Endometrial biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Three weeks after birth, an infant girl develops episodes of apnea. She has become increasingly lethargic over the past two days, and experienced two episodes of apnea lasting 10 seconds each within the last day. She was born at 31 weeks of gestation and weighed 1600-g (3-lb 8-oz). Apgar scores were 4 and 7 at 1 and 5 minutes, respectively. She takes no medications. Her temperature is 36.7°C (98.0°F), pulse is 185/min, respirations are 60/min and irregular, and blood pressure is 70/35 mm Hg. She appears pale. Physical examination shows no abnormalities. Laboratory studies show a hemoglobin of 6.5 g/dL, a reticulocyte count of 0.5%, and a mean corpuscular volume of 92 μm3. Leukocyte count, platelet count, total bilirubin and indirect bilirubin are all within reference range. Which of the following is the most likely underlying mechanism of this patient's anemia?", "answer": "Impaired erythropoietin production", "options": {"A": "Defective δ-aminolevulinic acid synthase", "B": "Bone marrow suppression", "C": "Glucose-6-phosphate dehydrogenase deficiency", "D": "Iron deficiency", "E": "Impaired erythropoietin production"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old woman presents to the physician with a 6-month history of progressive shortness of breath. She now has to stop to rest three or four times whenever she climbs the stairs to her apartment on the third floor. She reports chronic, nonproductive cough and wheezing, for which she uses ipratropium inhalers. She has a 25 pack-year smoking history. On examination, the blood pressure is 130/80 mm Hg, the pulse rate is 95/min, the temperature is 36.6°C (97.8°F), and the respiratory rate is 26/min. Chest auscultation reveals bilateral crepitations. Cardiac auscultation reveals normal S1 and S2 without murmurs or added sounds. Arterial blood gas analysis shows:\npH 7.36 (reference: 7.35–7.45)\nHCO3- 32 mEq/L  (reference 22–28 mEq/L)\nPco2 48 mm Hg  (reference: 33–45 mm Hg)\nPo2 63 mm Hg (reference: 75–105 mm Hg)\nO2 saturation 91% (reference: 94–99%)\nWhich of the following would you expect to find in this patient?", "answer": "Decreased diffusing capacity of the lungs for carbon monoxide (DLCO)", "options": {"A": "Decreased lung residual volume", "B": "Decreased diffusing capacity of the lungs for carbon monoxide (DLCO)", "C": "Increased FEV1/FVC ratio", "D": "Shift of the flow volume loop to the right", "E": "Decreased lung compliance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old man is brought to a psychiatrist by his mother who is concerned that he has become increasingly distant. When asked, he says that he is no longer going out because he is afraid of going outside by himself. He says that ever since he was a teenager, he was uncomfortable in large crowds and on public transportation. He now works from home and rarely leaves his house except on mandatory business. Which of the following personality disorders is most likely genetically associated with this patient's disorder?", "answer": "Dependent", "options": {"A": "Antisocial", "B": "Dependent", "C": "Histrionic", "D": "Paranoid", "E": "Schizotypal"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old woman presents with sudden-onset pain in her lower back. She says she was exercising in the gym several hours ago when she felt a sharp pain. The pain is radiating down the side of her leg and into her foot. On physical exam, her vital signs are as follows: HR 95, BP 120/70, T 37.2 degrees C. She has extreme pain shooting down her leg with a straight leg raise. Her sensation to light touch and pin-prick is intact throughout. Which of the following is the most likely diagnosis?", "answer": "Disc herniation", "options": {"A": "Disc herniation", "B": "Osteomyelitis", "C": "Cauda equina syndrome", "D": "Spinal stenosis", "E": "Ankylosing spondylitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old man with AIDS comes to the physician because of a 2-day history of decreasing vision and seeing black spots in his right eye. He has no pain and the left eye is asymptomatic. He was treated for fungal esophagitis 6 months ago with fluconazole. He was diagnosed with Kaposi's sarcoma 2 years ago. Current medications include efavirenz, tenofovir, emtricitabine, azithromycin, trimethoprim-sulfamethoxazole, multivitamins, and a nutritional supplement. He is 170 cm (5 ft 7 in) tall and weighs 45 kg (99 lbs);BMI is 15.6 kg/m2. His temperature is 37°C (98.6°F), pulse is 89/min, and blood pressure is 110/70 mm Hg. Examination shows cervical lymphadenopathy. There are multiple violaceous plaques seen over his trunk and extremities. Fundoscopic examination shows granular yellow-white opacities around the retinal vessels and multiple areas of dot-blot hemorrhages. His CD4+ T-lymphocyte count is 36/mm3. Which of the following is the most likely diagnosis?", "answer": "Cytomegalovirus retinitis", "options": {"A": "Cytomegalovirus retinitis", "B": "Herpes simplex keratitis", "C": "Toxoplasma retinitis", "D": "HIV retinopathy", "E": "Varicella zoster retinitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year old man comes to the physician because of a painless neck lump and a 2-month history of difficulty swallowing. He has a history of recurrent nephrolithiasis and episodic hypertension. Physical examination shows a 3 × 3-cm, nontender nodule at the level of the thyroid cartilage. A photomicrograph of a section of tissue obtained by core needle biopsy of the nodule is shown. Which of the following is the most likely diagnosis?", "answer": "Medullary carcinoma", "options": {"A": "Follicular carcinoma", "B": "Anaplastic carcinoma", "C": "Non-Hodgkin lymphoma", "D": "Papillary carcinoma", "E": "Medullary carcinoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old boy is brought to the physician because of increasing pain and swelling of his right knee for 12 days. He has had episodes of pain with urination for 3 weeks. He had a painful, swollen left ankle joint that resolved without treatment one week ago. His mother has rheumatoid arthritis. He is sexually active with 2 female partners and uses condoms inconsistently. He appears anxious. His temperature is 38°C (100.4°F), pulse is 68/min, and blood pressure is 100/80 mm Hg. Examination shows bilateral inflammation of the conjunctiva. The right knee is tender, erythematous, and swollen; range of motion is limited by pain. There is tenderness at the left Achilles tendon insertion site. Genital examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14.5 g/dL\nLeukocyte count 12,300/mm3\nPlatelet count 310,000/mm3\nErythrocyte sedimentation rate 38 mm/h\nSerum\nUrea nitrogen 18 mg/dL\nGlucose 89 mg/dL\nCreatinine 1.0 mg/dL\nUrine\nProtein negative\nBlood negative\nWBC 12–16/hpf\nRBC 1–2/hpf\nAn ELISA test for HIV is negative. Arthrocentesis is done. The synovial fluid is cloudy and a Gram stain is negative. Analysis of the synovial fluid shows a leukocyte count of 26,000/mm3 and 75% neutrophils. Which of the following is the most likely diagnosis?\"", "answer": "Reactive arthritis", "options": {"A": "Septic arthritis", "B": "Rheumatoid arthritis", "C": "Lyme arthritis", "D": "Reactive arthritis", "E": "Syphilitic arthritis\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old man presents to his primary care provider to discuss the frequency with which he wakes up at night to urinate. He avoids drinking liquids at night, but the symptoms have progressively worsened. The medical history is significant for hypertension and hyperlipidemia. He takes lisinopril, atorvastatin, and a multivitamin every day. Today, the vital signs include: blood pressure 120/80 mm Hg, heart rate 90/min, respiratory rate 17/min, and temperature 37.0°C (98.6°F). On physical examination, he appears tired. The heart has a regular rate and rhythm and the lungs are clear to auscultation bilaterally. A bedside bladder ultrasound reveals a full bladder. A digital rectal exam reveals an enlarged and symmetric prostate free of nodules, that is consistent with benign prostatic enlargement. He also has a history of symptomatic hypotension with several episodes of syncope in the past. The patient declines a prostate biopsy that would provide a definitive diagnosis and requests less invasive treatment. Which of the following is recommended to treat this patient’s enlarged prostate?", "answer": "Finasteride", "options": {"A": "Tamsulosin", "B": "Finasteride", "C": "Prazosin", "D": "Tadalafil", "E": "Leuprolide"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 63-year-old man comes to the physician for the evaluation of a skin lesion on his chest. He first noticed the lesion 2 months ago and thinks that it has increased in size since then. The lesion is not painful or pruritic. He has type 2 diabetes mellitus, hypercholesterolemia, and glaucoma. The patient has smoked 1 pack of cigarettes daily for the last 40 years and drinks two to three beers on the weekend. Current medications include metformin, atorvastatin, topical timolol, and a multivitamin. Vital signs are within normal limits. The lesion is partly elevated on palpation and does not change its form on pinching. A photograph of the lesion is shown. Which of the following is the most likely diagnosis?", "answer": "Malignant melanoma", "options": {"A": "Malignant melanoma", "B": "Keratoacanthoma", "C": "Lentigo maligna", "D": "Seborrheic keratosis", "E": "Basal cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A case-control study looking to study the relationship between infection with the bacterium Chlamydia trachomatis and having multiple sexual partners was conducted in the United States. A total of 100 women with newly diagnosed chlamydial infection visiting an outpatient clinic for sexually transmitted diseases (STDs) were compared with 100 women from the same clinic who were found to be free of chlamydia and other STDs. The women diagnosed with this infection were informed that the potential serious consequences of the disease could be prevented only by locating and treating their sexual partners. Both groups of women were queried about the number of sexual partners they had had during the preceding 3 months. The group of women with chlamydia reported an average of 4 times as many sexual partners compared with the group of women without chlamydia; the researchers, therefore, concluded that women with chlamydia visiting the clinic had significantly more sexual partners compared with women who visited the same clinic but were not diagnosed with chlamydia. What type of systematic error could have influenced the results of this study?", "answer": "Reporting bias", "options": {"A": "Ascertainment bias", "B": "Lost-to-follow-up bias", "C": "Response bias", "D": "Detection bias", "E": "Reporting bias"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old man is brought to the emergency department 3 hours after being bitten by a rattlesnake. He was hiking in the Arizona desert when he accidentally stepped on the snake and it bit his right leg. His pulse is 135/min and blood pressure is 104/81 mm Hg. Examination shows right lower leg swelling, ecchymosis, and blistering. Right ankle dorsiflexion elicits severe pain. A manometer inserted in the lateral compartment of the lower leg shows an intracompartmental pressure of 67 mm Hg. In addition to administration of the antivenom, the patient undergoes fasciotomy. Two weeks later, he reports difficulty in walking. Neurologic examination shows a loss of sensation over the lower part of the lateral side of the right leg and the dorsum of the right foot. Right foot eversion is 1/5. There is no weakness in dorsiflexion. Which of the following nerves is most likely injured in this patient?", "answer": "Superficial peroneal nerve", "options": {"A": "Tibial nerve", "B": "Sural nerve", "C": "Deep peroneal nerve", "D": "Superficial peroneal nerve", "E": "Saphenous nerve"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old woman visits the clinic with chronic diarrhea on most days for the past four months. She also complains of lower abdominal discomfort and cramping, which is relieved by episodes of diarrhea. She denies any recent change in her weight. Bowel movements are preceded by a sensation of urgency, associated with mucus discharge, and followed by a feeling of incomplete evacuation. The patient went camping several months earlier, and another member of her camping party fell ill recently. Her temperature is 37° C (98.6° F), respiratory rate is 15/min, pulse is 67/min, and blood pressure is 122/98 mm Hg. Her physical examination is unremarkable. A routine stool examination is within normal limits and blood test results show:\nHb%   13 gm/dL\nTotal count (WBC):   11,000/mm3\nDifferential count:    \n  Neutrophils: 70%\n  Lymphocytes: 25%\n  Monocytes: 5%\nESR:   10 mm/hr\nWhat is the most likely diagnosis?", "answer": "Irritable bowel syndrome", "options": {"A": "Irritable bowel syndrome", "B": "Crohn’s disease", "C": "Ulcerative colitis", "D": "Giardiasis", "E": "Laxative abuse"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old man presents to his primary care physician for a persistent and low grade headache as well as trouble focusing. The patient was seen in the emergency department 3 days ago after hitting his head on a branch while biking under the influence of alcohol. His head CT at the time was normal, and the patient was sent home with follow up instructions. Since the event, he has experienced trouble focusing on his school work and feels confused at times while listening to lectures. He states that he can’t remember the lectures and also says he has experienced a sensation of vertigo at times. On review of systems, he states that he has felt depressed lately and has had trouble sleeping, though he denies any suicidal or homicidal ideation. His temperature is 98.2°F (36.8°C), blood pressure is 122/65 mmHg, pulse is 70/min, respirations are 12/min, and oxygen saturation is 98% on room air. The patient’s neurological and cardiopulmonary exam are within normal limits. Which of the following is the best next step in management?", "answer": "Rest and primary care follow up", "options": {"A": "Cognitive behavioral therapy", "B": "CT scan of the head without contrast", "C": "Fluoxetine", "D": "Rest and primary care follow up", "E": "Thiamine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "While playing the catcher position in baseball, a 27-year-old male sustained a blow to his left testes which required surgical removal. Upon awakening from anesthesia, he jokes to his wife that he is now half the man that she once knew. Which of the following scenarios is a similar ego defense as the one above?", "answer": "A recently divorced man states he will finally be able to watch a football game without nagging", "options": {"A": "A religious woman with homosexual desires speaks out against gay marriage", "B": "A husband angry at his wife takes out his anger on his employees", "C": "A short-tempered male lifts weights to deal with his anger", "D": "A cheating husband accuses his wife of doing the same", "E": "A recently divorced man states he will finally be able to watch a football game without nagging"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old man comes to the physician because of severe muscle pain and fever for 4 days. He likes to go hunting and consumed bear meat 1 month ago. Examination shows periorbital edema and generalized muscle tenderness. His leukocyte count is 12,000/mm3 with 19% eosinophils. The release of major basic protein in response to this patient’s infection is most likely a result of which of the following?", "answer": "Antibody-dependent cell-mediated cytotoxicity", "options": {"A": "Immune complex-dependent complement activation", "B": "Interaction between Th1 cells and macrophages", "C": "Increased expression of MHC class I molecules", "D": "Increased expression of MHC class II molecules", "E": "Antibody-dependent cell-mediated cytotoxicity"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old patient with a history of COPD and open-angle glaucoma in the left eye has had uncontrolled intraocular pressure (IOP) for the last few months. She is currently using latanoprost eye drops. Her ophthalmologist adds another eye drop to her regimen to further decrease her IOP. A week later, the patient returns because of persistent dim vision. On exam, she has a small fixed pupil in her left eye as well as a visual acuity of 20/40 in her left eye compared to 20/20 in her right eye. Which of the following is the mechanism of action of the medication most likely prescribed in this case?", "answer": "Opening the canal of Schlemm by contracting the ciliary muscle", "options": {"A": "Inhibiting the production of aqueous humor by the ciliary epithelium", "B": "Closing the trabecular mesh by relaxing the ciliary muscles", "C": "Opening the canal of Schlemm by contracting the ciliary muscle", "D": "Increasing reabsorption of aqueous humor by the ciliary epithelium", "E": "Increasing the permeability of sclera to aqueous humor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old man presents to the clinic with a 10-day history of a sore throat and fever. He has a past medical history significant for ulcerative colitis and chronic lower back pain. He smokes at least 1 pack of cigarettes daily for 10 years. The father of the patient died of colon cancer at the age of 50. He takes sulfasalazine and naproxen. The temperature is 38.9°C (102.0°F), the blood pressure is 131/87 mm Hg, the pulse is 74/min, and the respiratory rate is 16/min. On physical examination, the patient appears tired and ill. His pharynx is erythematous with exudate along the tonsillar crypts. The strep test comes back positive. In addition to treating the bacterial infection, what else would you recommend for the patient at this time?", "answer": "Colonoscopy", "options": {"A": "Fecal occult blood testing", "B": "Flexible sigmoidoscopy", "C": "Low-dose CT", "D": "Colonoscopy", "E": "PSA and digital rectal exam"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A patient with HCC and a long history of alcohol dependence and chronic hepatitis C has been using the mTOR inhibitor Metalimus 100 mg for cancer treatment. Her cancer has shown a partial response. She also has a history of hypertension and poorly controlled type 2 diabetes mellitus complicated by diabetic retinopathy. Current medications include enalapril and insulin. She asks her oncologist and hepatologist if she could try Noxbinle (tumorolimus) for its purported survival benefit in treating HCC. Based on the data provided in the drug advertisement, which of the following statements is most accurate?", "answer": "The patient is not a good candidate for Noxbinle due to her history of diabetes", "options": {"A": "The patient is not a good candidate for Noxbinle due to her history of hypertension", "B": "The patient is not a good candidate for Noxbinle due to her history of diabetes", "C": "The patient should start Noxbinle 50 mg because of the survival benefit relative to Metalimus 100 mg", "D": "The patient should start Noxbinle 100 mg because of the survival benefit relative to Metalimus 100 mg", "E": "The patient should start Noxbinle 50 mg because of her history of alcohol use disorder and hepatitis C"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old G4P2 at 35 weeks gestation presents to the hospital after she noticed that \"her water broke.\" Her prenatal course is unremarkable, but her obstetric history includes postpartum hemorrhage after her third pregnancy, attributed to a retained placenta. The patient undergoes augmentation of labor with oxytocin and within four hours delivers a male infant with Apgar scores of 8 and 9 at 1 and 5 minutes, respectively. Three minutes later, the placenta passes the vagina, but a smooth mass attached to the placenta continues to follow. Her temperature is 98.6°F (37°C), blood pressure is 110/70 mmHg, pulse is 90/min, and respirations are 20/min. What is the most likely complication in the absence of intervention?", "answer": "Hemorrhagic shock", "options": {"A": "Heart failure", "B": "Hemorrhagic shock", "C": "Hypertension", "D": "Hyperthermia", "E": "Tachypnea"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old nulliparous woman with no significant medical history presents to your office with shortness of breath and increased abdominal girth over the past month. The initial assessment demonstrates that the patient has a right-sided hydrothorax, ascites, and a large ovarian mass. Surgery is performed to remove the ovarian mass, and the patient's ascites and pleural effusion resolve promptly. What is the most likely diagnosis?", "answer": "Meigs syndrome", "options": {"A": "Metastatic colon cancer", "B": "Metastatic lung cancer", "C": "Metastatic ovarian cancer", "D": "Meigs syndrome", "E": "Nephrotic syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man comes to the physician for a follow-up examination. He has a 2-month history of increasing generalized fatigue and severe pruritus. He has hypertension and ulcerative colitis which was diagnosed via colonoscopy 5 years ago. Current medications include lisinopril and rectal mesalamine. He is sexually active with 2 female partners and uses condoms inconsistently. His temperature is 37.3°C (99.1°F), pulse is 86/min, and blood pressure is 130/84 mm Hg. Examination shows scleral icterus and multiple scratch marks on the trunk and extremities. The lungs are clear to auscultation. The abdomen is soft and nontender. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11.5 g/dL\nLeukocyte count 7500/mm3\nPlatelet count 280,000/mm3\nSerum\nNa+ 138 mEq/L\nCl- 101 mEq/L\nK+ 4.7 mEq/L\nUrea nitrogen 18 mg/dL\nGlucose 91 mg/dL\nCreatinine 0.8 mg/dL\nBilirubin\nTotal 1.5 mg/dL\nDirect 0.9 mg/dL\nAlkaline phosphatase 460 U/L\nAST 75 U/L\nALT 78 U/L\nAnti-nuclear antibody negative\nAntimitochondrial antibodies negative\nAbdominal ultrasound shows thickening of the bile ducts and focal bile duct dilatation. Which of the following is the most likely diagnosis?\"", "answer": "Primary sclerosing cholangitis", "options": {"A": "Autoimmune hepatitis", "B": "Primary sclerosing cholangitis", "C": "Primary biliary cholangitis", "D": "Hepatitis B infection", "E": "IgG4-associated cholangitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 82-year-old woman is brought to the emergency department after losing consciousness at her nursing home. She had been watching TV for several hours and while getting up to use the bathroom, she fell and was unconscious for several seconds. She felt dizzy shortly before the fall. She does not have a headache or any other pain. She has a history of hypertension, intermittent atrial fibrillation, and stable angina pectoris. Current medications include warfarin, aspirin, hydrochlorothiazide, and a nitroglycerin spray as needed. Her temperature is 36.7°C (98.1°F), pulse is 100/min and regular, and blood pressure is 102/56 mm Hg. Physical exam shows a dry tongue. A fold of skin that is pinched on the back of her hand unfolds after 2 seconds. Cardiopulmonary examination shows no abnormalities. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Elevated blood urea nitrogen concentration", "options": {"A": "Elevated serum concentration of cardiac enzymes", "B": "Absent P waves on ECG", "C": "Elevated blood urea nitrogen concentration", "D": "Hypodense lesions on CT scan of the head", "E": "Elevated serum creatine kinase concentration"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old woman comes to the physician because of a 10-month history of nonbloody diarrhea and recurrent episodes of flushing and wheezing. She does not take any medications. Physical examination shows a hyperpigmented rash around the base of her neck. Cardiac examination shows a grade 4/6, holosystolic murmur in the 5th intercostal space at the left midclavicular line. Echocardiography shows left-sided endocardial and valvular fibrosis with moderate mitral regurgitation; there are no septal defects or right-sided valvular defects. Urinalysis shows increased 5-hydroxyindoleacetic acid concentration. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Tumor in the lung without metastasis", "options": {"A": "Tumor in the pancreas without metastasis", "B": "Tumor in the lung without metastasis", "C": "Tumor in the left atrium with hepatic metastasis", "D": "Tumor in the appendix without metastasis", "E": "Tumor in the descending colon with hepatic metastasis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-year-old boy is brought to the clinic by his mother with fever and a rash. The patient’s mother says his symptoms started 1 week ago with the acute onset of fever and a runny nose, which resolved over the next 3 days. Then, 4 days later, she noted a rash on his face, which, after a day, spread to his neck, torso, and extremities. The patient denies any pruritus or pain associated with the rash. No recent history of sore throat, chills, or upper respiratory infection. The patient has no significant past medical history and takes no medications. The vital signs include: temperature 37.2°C (99.9°F) and pulse 88/min. On physical examination, there is a maculopapular rash on his face, torso, and extremities, which spares the palms and soles. The appearance of the rash is shown in the exhibit (see image below). Which of the following would most likely confirm the diagnosis in this patient?", "answer": "ELISA for parvovirus B-19 IgM and IgG antibodies", "options": {"A": "Throat culture", "B": "Assay for IgM and IgG against measles virus", "C": "Serology for human herpesvirus-6 IgM antibodies", "D": "ELISA for IgG antibodies against Rubella virus", "E": "ELISA for parvovirus B-19 IgM and IgG antibodies"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old woman presents to her physician’s office complaining of a worsening cough with large volumes of mucoid sputum in her phlegm every morning and thickened foul smell sputum almost every time she coughs. She says that this cough started about one month ago and has been increasing in intensity. Over the counter medications are ineffective. Past medical history is significant for cystic fibrosis diagnosed at the age of 6 years old, and pneumonia twice in the past 2 years. Other than a cough, she has no fever or any other concerns. A sputum samples grows aerobic, non-lactose fermenting, oxidase-positive, gram-negative bacillus. Which of the following treatment regimens is the most beneficial for her at this time?", "answer": "Intravenous ciprofloxacin", "options": {"A": "Amoxicillin and clavulanic acid", "B": "Postural drainage of the chest", "C": "Surgical therapy", "D": "Trimethoprim and sulfamethoxazole", "E": "Intravenous ciprofloxacin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 7-month-old boy is brought to the pediatrician for a change in his behavior. The patient has been breastfeeding up until this point and has been meeting his developmental milestones. He is in the 90th percentile for weight and 89th percentile for height. This past week, the patient has been lethargic, vomiting, and has been refusing to eat. The patient's parents state that he had an episode this morning where he was not responsive and was moving his extremities abnormally followed by a period of somnolence. The patient's past medical history is notable for shoulder dystocia and poorly managed maternal diabetes during the pregnancy. His temperature is 99.5°F (37.5°C), blood pressure is 60/30 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. On physical exam, you note a lethargic infant with a sweet smell to his breath. Which of the following is most likely deficient in this patient?", "answer": "Aldolase B", "options": {"A": "Aldolase B", "B": "Galactose-1-phosphate uridyltransferase", "C": "Glucose", "D": "Branched chain alpha-ketoacid dehydrogenase", "E": "Ornithine transcarbamolase"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old woman is admitted to the hospital for severe malnutrition with a BMI of 15 kg/m2. Past medical history is significant for chronic anorexia nervosa. During the course of her stay, she is treated with parenteral fluids and nutrition management. On the 4th day, her status changes. Her blood pressure is 110/75 mm Hg, heart rate is 120/min, respiratory rate is 25/min, and temperature is 37.0°C (98.6°F). On physical exam, her heart is tachycardic with a regular rhythm and her lungs are clear to auscultation bilaterally. She appears confused, disoriented, and agitated. Strength in her lower extremities is 4/5. What is the next step in management?", "answer": "Measure electrolytes", "options": {"A": "MRI of the brain", "B": "Arrange for outpatient counseling", "C": "Measure electrolytes", "D": "Administer insulin", "E": "Doppler ultrasound on lower extremities"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old man comes to the physician because of a 5-day history of fatigue, fever, and chills. For the past 9 months, he has had hand pain and stiffness that has progressively worsened. He started a new medication for these symptoms 3 months ago. Medications used prior to that included ibuprofen, prednisone, and hydroxychloroquine. He does not smoke or drink alcohol. Examination shows a subcutaneous nodule at his left elbow, old joint destruction with boutonniere deformity, and no active joint warmth or tenderness. The remainder of the physical examination shows no abnormalities. His hemoglobin concentration is 10.5 g/dL, leukocyte count is 3500/mm3, and platelet count is 100,000/mm3. Which of the following is most likely to have prevented this patient's laboratory abnormalities?", "answer": "Leucovorin", "options": {"A": "Cobalamin", "B": "Amifostine", "C": "Pyridoxine", "D": "Leucovorin", "E": "Mesna\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Please refer to the summary above to answer this question\nAn ECG is most likely to show which of the following findings in this patient?\"\n\"Patient Information\nAge: 64 years\nGender: F, self-identified\nEthnicity: unspecified\nSite of Care: emergency department\nHistory\nReason for Visit/Chief Concern: “My chest hurts, especially when I take a deep breath.”\nHistory of Present Illness:\n2-hour history of chest pain\npain described as “sharp”\npain rated 6/10 at rest and 10/10 when taking a deep breath\nPast Medical History:\nrheumatoid arthritis\nmajor depressive disorder\nMedications:\nmethotrexate, folic acid, fluoxetine\nAllergies:\npenicillin\nPsychosocial History:\ndoes not smoke\ndrinks one glass of bourbon every night\nPhysical Examination\nTemp Pulse Resp BP O2 Sat Ht Wt BMI\n36.7°C\n(98°F)\n75/min 17/min 124/75 mm Hg –\n163 cm\n(5 ft 4 in)\n54 kg\n(120 lb)\n20 kg/m2\nAppearance: sitting forward at the edge of a hospital bed, uncomfortable\nNeck: no jugular venous distension\nPulmonary: clear to auscultation\nCardiac: regular rate and rhythm; normal S1 and S2; no murmurs; a scratching sound is best heard over the left sternal border; pain is not reproducible on palpation; pain is worse when the patient is lying back and improved by leaning forward\nAbdominal: no tenderness, guarding, masses, bruits, or hepatosplenomegaly\nExtremities: tenderness to palpation, stiffness, and swelling of the metacarpophalangeal and proximal interphalangeal joints of the fingers; swan neck deformities and ulnar deviation of several fingers; firm, nontender nodules on the extensor aspects of the left forearm; no edema\nNeurologic: alert and oriented; cranial nerves grossly intact; no focal neurologic deficits\"", "answer": "Diffuse, concave ST-segment elevations", "options": {"A": "S waves in lead I, Q waves in lead III, and inverted T waves in lead III", "B": "Diffuse, concave ST-segment elevations", "C": "Sawtooth-appearance of P waves", "D": "Peaked T waves and ST-segment elevations in leads V1-V6", "E": "Alternating high and low amplitude QRS complexes"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 16-year-old boy is brought to the physician for a follow-up appointment. He has a seizure disorder treated with valproic acid. He has always had difficulties with his schoolwork. He was able to walk independently at the age of 2 years and was able to use a fork and spoon at the age of 3 years. Ophthalmic examination shows hyperpigmented iris nodules bilaterally. A photograph of his skin examination findings is shown. This patient is at increased risk for which of the following conditions?", "answer": "Pheochromocytoma", "options": {"A": "Vestibular schwannoma", "B": "Hemangioblastoma", "C": "Pheochromocytoma", "D": "Leptomeningeal angioma", "E": "Cardiac rhabdomyoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old woman presents to her primary care physician with a chief complaint of diarrhea. She states that it has been going on for the past month and started after she ate a burger cooked over a campfire. She endorses having lost 10 pounds during this time. The patient has no other complaints other than hoarseness which has persisted during this time. The patient has a past medical history of obesity, hypothyroidism, diabetes, and anxiety. Her current medications include insulin, metformin, levothyroxine, and fluoxetine. She currently drinks 4 to 5 alcoholic beverages per day. Her temperature is 99.5°F (37.5°C), blood pressure is 157/98 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. On physical exam, you note a healthy obese woman. Cardiopulmonary exam is within normal limits. HEENT exam is notable for a mass on the thyroid. Abdominal exam is notable for a candida infection underneath the patient's pannus. Pelvic exam is notable for a white, fish-odored discharge. Laboratory values are as follows:\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 4,500 cells/mm^3 with normal differential\nPlatelet count: 190,000/mm^3\n\nSerum:\nNa+: 141 mEq/L\nCl-: 102 mEq/L\nK+: 5.5 mEq/L\nHCO3-: 24 mEq/L\nGlucose: 122 mg/dL\nCa2+: 7.1 mg/dL\n\nWhich of the following could also be found in this patient?", "answer": "Episodic hypertension and headaches", "options": {"A": "Acute renal failure", "B": "Acute liver failure", "C": "Episodic hypertension and headaches", "D": "Bitemporal hemianopsia", "E": "Schistocytes"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old female presents to her OB/GYN for a check-up. During her visit, a pelvic exam and Pap smear are performed. The patient does not have any past medical issues and has had routine gynecologic care with normal pap smears every 3 years since age 21. The results of the Pap smear demonstrate atypical squamous cells of undetermined significance (ASCUS). Which of the following is the next best step in the management of this patient?", "answer": "Perform an HPV DNA test", "options": {"A": "Repeat Pap smear in 1 year", "B": "Repeat Pap smear in 3 years", "C": "Perform an HPV DNA test", "D": "Perform colposcopy", "E": "Perform a Loop Electrosurgical Excision Procedure (LEEP)"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 19-year-old man comes to the physician for the evaluation of progressive difficulty climbing stairs over the last 2 years. During this period, he has also had problems with running, occasional falls, and standing from a chair. He has not had any vision problems or muscle cramping. There is no personal or family history of serious illness. Neurological examination shows deep tendon reflexes are 2+ bilaterally and sensation to pinprick and light touch is normal. Musculoskeletal examination shows enlarged calf muscles bilaterally. He has a waddling gait. Laboratory studies show a creatine kinase level of 1700 U/L. Which of the following is the most appropriate next step to confirm the diagnosis?", "answer": "Genetic analysis", "options": {"A": "Tensilon test", "B": "Anti-Jo-1 antibodies measurement", "C": "CT scan of the chest", "D": "Electromyography", "E": "Genetic analysis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 11-year-old man presents with fever and joint pain for the last 3 days. His mother says that he had a sore throat 3 weeks ago but did not seek medical care at that time. The family immigrated from the Middle East 3 years ago. The patient has no past medical history. The current illness started with a fever and a swollen right knee that was very painful. The following day, his knee improved but his left elbow became swollen and painful. While in the waiting room, his left knee is also becoming swollen and painful. Vital signs include: temperature 38.7°C (101.6°F), and blood pressure 110/80 mm Hg. On physical examination, the affected joints are swollen and very tender to touch, and there are circular areas of redness on his back and left forearm (as shown in the image). Which of the following is needed to establish a diagnosis of acute rheumatic fever in this patient?", "answer": "Positive anti-streptococcal serology", "options": {"A": "Elevated erythrocyte sedimentation rate (ESR)", "B": "Elevated leukocyte count", "C": "No other criterion is needed to establish the diagnosis of acute rheumatic fever", "D": "Prolonged PR interval", "E": "Positive anti-streptococcal serology"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 41-year-old woman is referred by her radiation oncologist to the medical genetics clinic. She was recently diagnosed with an infiltrating ductal carcinoma of the breast. She has a previous history of colonic polyps for which she undergoes bi-annual colonoscopy. The maternal and paternal family history is unremarkable for polyps and malignant or benign tumors. However, the patient reports that her 10-year-old son has dark brown pigmentation on his lips, and she also had similar pigmentation as a child. Histology of colonic polyps in this patient will most likely reveal which of the following?", "answer": "Hamartomatous polyp", "options": {"A": "Hyperplastic polyps", "B": "Adenomatous polyps", "C": "Inflammatory polyps", "D": "Retention polyps", "E": "Hamartomatous polyp"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old woman presents to her primary care physician with a 5-month history of worsening bladder discomfort. Her discomfort is relieved by voiding. She voids 10–15 times per day and wakes up 2–3 times per night to void. She has not had any involuntary loss of urine. She has tried cutting down on fluids and taking NSAIDs to reduce the discomfort with minimal relief. Her past medical history is significant for bipolar disorder. She is sexually active with her husband but reports that intercourse has recently become painful. Current medications include lithium. Her temperature is 37°C (98.6°F), pulse is 65/min, and blood pressure is 110/80 mm Hg. Examination shows tenderness to palpation of her suprapubic region. Urinalysis shows:\nColor clear\npH 6.7\nSpecific gravity 1.010\nProtein 1+\nGlucose negative\nKetones negative\nBlood negative\nNitrite negative\nLeukocyte esterase negative\nWBC 0/hpf\nSquamous epithelial cells 2/hpf\nBacteria None\nA pelvic ultrasound shows a postvoid residual urine is 25 mL. A cystoscopy shows a normal urethra and normal bladder mucosa. Which of the following is the most likely diagnosis?\"", "answer": "Interstitial cystitis", "options": {"A": "Urinary tract infection", "B": "Overactive bladder", "C": "Interstitial cystitis", "D": "Urinary retention", "E": "Diabetes insipidus"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old woman presents to her primary care provider with a 2-month history of insidious onset of left shoulder pain. It only occurs at the extremes of her range of motion and has made it difficult to sleep on the affected side. She has noticed increasing difficulty with activities of daily living, including brushing her hair and putting on or taking off her blouse and bra. She denies a history of shoulder trauma, neck pain, arm/hand weakness, numbness, or paresthesias. Her medical history is remarkable for type 2 diabetes mellitus, for which she takes metformin and glipizide. Her physical examination reveals a marked decrease in both active and passive range of motion of the left shoulder, with forwarding flexion to 75°, abduction to 75°, external rotation to 45°, and internal rotation to 15° with significant pain. Rotator cuff strength is normal. AP, scapular Y, and axillary plain film radiographs are reported as normal. Which of the following is the most likely diagnosis?", "answer": "Adhesive capsulitis", "options": {"A": "Degenerative cervical spine disease", "B": "Adhesive capsulitis", "C": "Rotator cuff injury", "D": "Subacromial impingement syndrome", "E": "Glenohumeral arthritis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 70-year-old man comes to the physician because of right-sided back pain, red urine, and weight loss for the last 4 months. He has smoked one pack of cigarettes daily for 40 years. A CT scan of the abdomen shows a large right-sided renal mass. Biopsy of the mass shows polygonal clear cells filled with lipids. Which of the following features is necessary to determine the tumor grade in this patient?", "answer": "Degree of mitotic activity", "options": {"A": "Size of malignant proliferation", "B": "Invasion of surrounding structures", "C": "Degree of mitotic activity", "D": "Response to chemotherapy", "E": "Involvement of regional lymph nodes\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 46-year-old woman comes to her physician because of an itchy rash on her legs. She denies any recent trauma, insect bites, or travel. Her vital signs are within normal limits. Examination of the oral cavity shows white lace-like lines on the buccal mucosa. A photograph of the rash is shown. A biopsy specimen of the skin lesion is most likely to show which of the following?", "answer": "Lymphocytes at the dermoepidermal junction", "options": {"A": "Decreased thickness of the stratum granulosum", "B": "Inflammation of subcutaneous adipose tissue", "C": "Lymphocytes at the dermoepidermal junction", "D": "Proliferation of vascular endothelium", "E": "Deposition of antibodies around epidermal cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old female presents to the emergency room with mental status changes.\nLaboratory analysis of the patient's serum shows:\nNa 122 mEq/L\nK 3.9 mEq/L\nHCO3 24 mEq/L\nBUN 21 mg/dL\nCr 0.9 mg/dL\nCa 8.5 mg/dL\nGlu 105 mg/dL\n\nUrinalysis shows:\nOsmolality 334 mOsm/kg\nNa 45 mEq/L\nGlu 0 mg/dL\n\nWhich of the following is the most likely diagnosis?", "answer": "Lung cancer", "options": {"A": "Aspirin overdose", "B": "Diarrhea", "C": "Diabetes insipidus", "D": "Primary polydipsia", "E": "Lung cancer"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "On the 4th day of hospital admission due to pneumonia, a 69-year-old woman develops non-bloody diarrhea and abdominal pain. She is currently treated with ceftriaxone. Despite the resolution of fever after the first 2 days of admission, her temperature is now 38.5°C (101.3°F). On physical examination, she has mild generalized abdominal tenderness without abdominal guarding or rebound tenderness. Laboratory studies show re-elevation of leukocyte counts. Ceftriaxone is discontinued. Given the most likely diagnosis in this patient, which of the following is the most sensitive test?\n ", "answer": "Stool culture for bacterial isolation and toxin presence", "options": {"A": "Endoscopy ", "B": "Enzyme immunoassay glutamate dehydrogenase ", "C": "Gram stain of stool sample ", "D": "Nucleic acid amplification test", "E": "Stool culture for bacterial isolation and toxin presence"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2-year-old boy is brought to the physician for a well-child examination. Since infancy, he has frequently had large-volume stools that are loose and greasy. He was treated for otitis media twice in the past year. He has a history of recurrent respiratory tract infections since birth. He is at the 5th percentile for height and 3rd percentile for weight. Vital signs are within normal limits. Examination shows softening of the occipital and parietal bones. Scattered expiratory wheezing and rhonchi are heard throughout both lung fields. Which of the following is the most likely cause of this patient's symptoms?", "answer": "CFTR gene mutation", "options": {"A": "Deficient α1 antitrypsin", "B": "Gliadin autoantibodies", "C": "CFTR gene mutation", "D": "Absent T cells", "E": "Impaired ciliary function"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 77-year-old woman is brought to her primary care provider by her daughter with behavioral changes and an abnormally bad memory for the past few months. The patient’s daughter says she sometimes gets angry and aggressive while at other times she seems lost and stares at her surroundings. Her daughter also reports that she has seen her mother talking to empty chairs. The patient says she sleeps well during the night but still feels sleepy throughout the day. She has no problems getting dressed and maintaining her one bedroom apartment. Past medical history is significant for mild depression and mild osteoporosis. Current medications include escitalopram, alendronic acid, and a multivitamin. The patient is afebrile, and her vital signs are within normal limits. On physical examination, the patient is alert and oriented and sitting comfortably in her chair. A mild left-hand tremor is noted. Muscle strength is 5 out of 5 in the upper and lower extremities bilaterally, but muscle tone is slightly increased. She can perform repetitive alternating movements albeit slowly. She walks with a narrow gait and has mild difficulty turning. Which of the following is the most likely diagnosis in this patient?", "answer": "Lewy body dementia", "options": {"A": "Alzheimer's disease", "B": "Delirium", "C": "Frontotemporal dementia", "D": "Lewy body dementia", "E": "Serotonin syndrome"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 49-year-old man comes to the physician because of severe, shooting pain in his lower back for the past 2 weeks. The pain radiates down the back of both legs and started after he lifted a concrete manhole cover from the ground. Physical examination shows decreased sensation to light touch bilaterally over the lateral thigh area and lateral calf bilaterally. Patellar reflex is decreased on both sides. The passive raising of either the right or left leg beyond 30 degrees triggers a shooting pain down the leg past the knee. Which of the following is the most likely underlying cause of this patient's current condition?", "answer": "Herniation of nucleus pulposus into vertebral canal", "options": {"A": "Involuntary contraction of the paraspinal muscles", "B": "Inflammatory degeneration of the spine", "C": "Compromised integrity of the vertebral body", "D": "Herniation of nucleus pulposus into vertebral canal", "E": "Inflammatory reaction in the epidural space"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old patient with a past medical history of anxiety and appropriately treated schizophrenia presents to the emergency department for a first time seizure. The patient was at home eating dinner when he began moving abnormally and did not respond to his mother, prompting her to bring him in. His symptoms persisted in the emergency department and were successfully treated with diazepam. The patient is discharged and scheduled for a follow up appointment with neurology the next day for treatment. The patient returns to his neurologist 1 month later for a checkup. Physical exam is notable for carpopedal spasm when his blood pressure is being taken. Cranial nerves II-XII are grossly intact and his gait is stable. Which of the following is the most likely explanation of this patient's current presentation?", "answer": "P450 induction", "options": {"A": "Acute renal failure", "B": "Elevated blood levels of a medication", "C": "Increased water consumption", "D": "P450 induction", "E": "Sub-therapeutic dose"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old boy comes to the physician because of a 1-week history of difficulty swallowing, a foreign body sensation at the back of his throat, and trouble breathing at night. He has just recovered from an upper respiratory tract infection that began 5 days ago. On questioning, he reports that he has had similar symptoms in the past each time he has had an upper respiratory tract infection. Physical examination shows a 3 x 2-cm, nontender, rubbery midline mass at the base of the tongue. His skin is dry and cool. An image of his technetium-99m pertechnetate scan is shown. Which of the following is the most likely underlying cause of this patient’s condition?", "answer": "Arrested endodermal migration from pharyngeal floor", "options": {"A": "Ductal obstruction of the sublingual salivary glands", "B": "Chronic infection of the palatine and lingual tonsils", "C": "Arrested endodermal migration from pharyngeal floor", "D": "Persistent epithelial tract between the foramen cecum and thyroid isthmus", "E": "Failure of obliteration of the second branchial cleft"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 44-year-old man is brought by his coworkers to the emergency department 45 minutes after he became light-headed and collapsed while working in the boiler room of a factory. He did not lose consciousness. His coworkers report that 30 minutes prior to collapsing, he told them he was nauseous and had a headache. The patient appears sweaty and lethargic. He is not oriented to time, place, or person. The patient’s vital signs are as follows: temperature 41°C (105.8°F); heart rate 133/min; respiratory rate 22/min; and blood pressure 90/52 mm Hg. Examination shows equal and reactive pupils. Deep tendon reflexes are 2+ bilaterally. His neck is supple. A 0.9% saline infusion is administered. A urinary catheter is inserted and dark brown urine is collected. The patient’s laboratory test results are as follows:\nLaboratory test\nBlood\nHemoglobin 15 g/dL\nLeukocyte count 18,000/mm3\nPlatelet count 51,000/mm3\nSerum\nNa+ 149 mEq/L\nK+ 5.0 mEq/L\nCl- 98 mEq/L\nUrea nitrogen 42 mg/dL\nGlucose 88 mg/dL\nCreatinine 1.8 mg/dL\nAspartate aminotransferase (AST, GOT) 210\nAlanine aminotransferase (ALT, GPT) 250\nCreatine kinase 86,000 U/mL\nWhich of the following is the most appropriate next step in patient management?", "answer": "Ice water immersion", "options": {"A": "Acetaminophen therapy", "B": "Dantrolene", "C": "Evaporative cooling", "D": "Ice water immersion", "E": "Hemodialysis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old male anesthesiologist presents to the occupational health clinic after a needlestick exposure while obtaining an arterial line in a patient with cirrhosis. In addition to a standard bloodborne pathogen laboratory panel sent for all needlestick exposures at his hospital, additional hepatitis panels are ordered upon the patient's request. The patient's results are shown below:\n\nHIV 4th generation Ag/Ab: Negative/Negative\nHepatitis B surface antigen (HBsAg): Negative\nHepatitis C antibody: Negative\nAnti-hepatitis B surface antibody (HBsAb): Positive\nAnti-hepatitis B core IgM antibody (HBc IgM): Negative\nAnti-hepatitis B core IgG antibody (HBc IgG): Positive\n\nWhat is the most likely explanation of the results above?", "answer": "Immune due to infection", "options": {"A": "Acute infection", "B": "Chronic infection", "C": "Immune due to infection", "D": "Immune due to vaccination", "E": "Window period"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 75-year-old woman presents to her physician with a cough and shortness of breath. She says that cough gets worse at night and her shortness of breath occurs with moderate exertion or when lying flat. She says these symptoms have been getting worse over the last 6 months. She mentions that she has to use 3 pillows while sleeping in order to relieve her symptoms. She denies any chest pain, chest tightness, or palpitations. Past medical history is significant for hypertension and diabetes mellitus type 2. Her medications are amiloride, glyburide, and metformin. Family history is significant for her father who also suffered diabetes mellitus type 2 before his death at 90 years old. The patient says she drinks alcohol occasionally but denies any smoking history. Her blood pressure is 130/95 mm Hg, temperature is 36.5°C (97.7°F), and heart rate is 100/min. On physical examination, she has a sustained apical impulse, a normal S1 and S2, and a loud S4 without murmurs. There are bilateral crackles present bilaterally. A chest radiograph shows a mildly enlarged cardiac silhouette. A transesophageal echocardiogram is performed and shows a normal left ventricular ejection fraction. Which of the following myocardial changes is most likely present in this patient?", "answer": "Ventricular hypertrophy with sarcomeres duplicated in parallel", "options": {"A": "Ventricular hypertrophy with sarcomeres duplicated in series", "B": "Macrophages with hemosiderin", "C": "Ventricular hypertrophy with sarcomeres duplicated in parallel", "D": "Asymmetric hypertrophy of the interventricular septum", "E": "Granuloma consisting of lymphocytes, plasma cells and macrophages surrounding necrotic"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old woman presents to the emergency department with a 2-hour history of sharp chest pain. She says that the pain is worse when she inhales and is relieved by sitting up and leaning forward. Her past medical history is significant for rheumatoid arthritis, myocardial infarction status post coronary artery bypass graft, and radiation for breast cancer 20 years ago. Physical exam reveals a rubbing sound upon cardiac auscultation as well as increased jugular venous distention on inspiration. Pericardiocentesis is performed revealing grossly bloody fluid. Which of the following is most specifically associated with this patient's presentation?", "answer": "Malignancy", "options": {"A": "Malignancy", "B": "Myocardial infarction", "C": "Rheumatoid arthritis", "D": "Uremia", "E": "Viral illness"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Four days after admission to the hospital for anorexia nervosa, a 20-year-old woman has new-onset palpitations and paresthesias in all four limbs. Prior to admission, she was found unconscious by her parents on the floor of a residential treatment center. The patient was started on a trial of nutritional rehabilitation upon arrival to the hospital. Her temperature is 36°C (96.8°F), pulse is 47/min, and blood pressure is 90/60 mmHg. She is 160 cm tall and weighs 35 kg; BMI is 14 kg/m2. The patient appears emaciated. Examination shows lower leg edema. A 2/6 holosystolic murmur is heard over the 5th intercostal space at the midclavicular line. AN ECG shows intermittent supraventricular tachycardia and QTc prolongation. Serum studies show:\nDay 2 Day 4\nPotassium (mEq/L) 3.5 2.7\nCalcium (mg/dL) 8.5 7.8\nMagnesium (mEq/L) 1.2 0.5\nPhosphorus (mg/dL) 3.6 1.5\nWhich of the following is the most likely underlying cause of this patient's condition?\"", "answer": "Increased insulin release", "options": {"A": "Thiamine deficiency", "B": "Rapid gastric emptying", "C": "Uncompensated metabolic alkalosis", "D": "Increased insulin release", "E": "Euthyroid sick syndrome"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old boy comes to the emergency department because of a 3-day history of pain in his left wrist. That morning the pain increased and he started to have chills and malaise. Last week he had self-resolving left knee pain. He is otherwise healthy and has not had any trauma to the wrist. He recently returned from a camping trip to Minnesota. He is sexually active with one female partner, who uses a diaphragm for contraception. His temperature is 37.7°C (99.9°F). Examination shows several painless violaceous vesiculopustular lesions on the dorsum of both wrists and hands; two lesions are present on the left palm. There is swelling and erythema of the left wrist with severe tenderness to palpation and passive movement. Which of the following is the most likely diagnosis?", "answer": "Disseminated gonococcal infection", "options": {"A": "Lyme arthritis", "B": "Acute rheumatic fever", "C": "Systemic lupus erythematosus", "D": "Disseminated gonococcal infection", "E": "Reactive arthritis\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old man with obesity and heart disease presents to your outpatient clinic with complaints of orthopnea, significant dyspnea on minimal exertion, nausea, vomiting, and diarrhea. He says that his old doctor gave him \"some pills\" that he takes in varying amounts every morning. Physical exam is significant for a severely displaced point of maximal impulse, bilateral rales in the lower lung fields, an S3 gallop, and hepatomegaly. You decide to perform an EKG (shown in figure A). Suddenly, his rhythm changes to ventricular tachycardia followed by ventricular fibrillation, and he syncopizes and expires despite resuscitative efforts. High levels of which medication are most likely responsible?", "answer": "Digoxin", "options": {"A": "Digoxin", "B": "Propranolol", "C": "Verapamil", "D": "Amiodarone", "E": "Lidocaine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old African-American boy presents to his physician with fatigue, bone and abdominal pain, and mild jaundice. The pain is dull and remitting, and the patient complains it sometimes migrates from one extremity to another. His mother reports that his jaundice and pain have occurred periodically for the past 5 years. At the time of presentation, his vital signs are as follows: the blood pressure is 80/50 mm Hg, the heart rate is 87/min, the respiratory rate is 17/min, and the temperature is 36.5°C (97.7°F). On physical examination, the patient appears to be pale with mildly icteric sclera and mucous membranes. On auscultation, there is a soft systolic ejection murmur, and palpation reveals hepatosplenomegaly. His musculoskeletal examination shows no abnormalities. Laboratory investigations show the following results:\nComplete blood count\nErythrocytes\n3.7 x 106/mm3\nHgb\n11 g/dL\nTotal leukocyte count\nNeutrophils\nLymphocytes\nEosinophils\nMonocytes\nBasophils\n7,300/mm3\n51%\n40%\n2%\n7%\n0\nPlatelet count\n151,000/mm3\nChemistry\nTotal bilirubin\n3.1 mg/dL (53 µmol/L)\nDirect bilirubin\n0.5 mg/dL (8.55 µmol/L)\nA peripheral blood smear shows numerous sickle-shaped red blood cells. Among other questions, the patient’s mother asks you how his condition would influence his vaccination schedule. Which of the following statements is true regarding vaccination in this patient?", "answer": "The patient should receive serogroup B meningococcal vaccination at the age of 10 years.", "options": {"A": "The patient should not receive meningococcal, pneumococcal, or Haemophilus influenzae vaccines, because they are likely to cause complications or elicit disease in his case.", "B": "The patient should receive serogroup B meningococcal vaccination at the age of 10 years.", "C": "The patient should receive serogroup D meningococcal vaccination as soon as possible, because he is at higher risk of getting serogroup B meningococcal infection than other children.", "D": "The patient should receive the pneumococcal polysaccharide vaccine as soon as possible, because he is at higher risk of getting pneumococcal infection than other children.", "E": "The patient’s condition does not affect his chances to get any infection; thus, additional vaccinations are not advised."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man presents to his primary care physician for generalized pain. The patient states that he feels like his muscles and bones are in constant pain. This has persisted for the past several weeks, and his symptoms have not improved with use of ibuprofen or acetaminophen. The patient has a past medical history of alcohol abuse, repeat episodes of pancreatitis, constipation, and anxiety. He has a 22 pack-year smoking history. His temperature is 99.5°F (37.5°C), blood pressure is 140/95 mmHg, pulse is 70/min, respirations are 15/min, and oxygen saturation is 99% on room air. On physical exam, you note generalized tenderness/pain of the patient's extremities. Abdominal exam reveals normoactive bowel sounds and is non-tender. Dermatologic exam is unremarkable. Laboratory values are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 7,500/mm^3 with normal differential\nPlatelet count: 147,000/mm^3\n\nSerum:\nNa+: 138 mEq/L\nCl-: 100 mEq/L\nK+: 4.2 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.2 mg/dL\nAlkaline phosphatase: 252 U/L\nLipase: 30 U/L\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following is associated with this patient's condition?", "answer": "Hearing loss", "options": {"A": "Hearing loss", "B": "Bence Jones proteins", "C": "Hypercalcemia", "D": "Adenocarcinoma of the gallbladder", "E": "Obstructive jaundice"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old woman comes to the physician because of a 3-day history of redness, foreign body sensation, and discharge of both eyes. She reports that her eyes feel “stuck together” with yellow crusts every morning. She has a 3-year history of nasal allergies; her sister has allergic rhinitis. She is sexually active with 2 male partners and uses an oral contraceptive; they do not use condoms. Vital signs are within normal limits. Visual acuity is 20/20 in both eyes. Ophthalmic examination shows edema of both eyelids, bilateral conjunctival injection, and a thin purulent discharge. Examination of the cornea, anterior chamber, and fundus is unremarkable. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate pharmacotherapy?", "answer": "Topical erythromycin", "options": {"A": "Topical natamycin", "B": "Topical prednisolone acetate", "C": "Topical erythromycin", "D": "Artificial tears", "E": "Oral erythromycin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 59-year-old man is brought to the emergency department by paramedics following a high-speed motor vehicle collision. The patient complains of excruciating chest pain, which he describes as tearing. Further history reveals that the patient is healthy, taking no medications, and is not under the influence of drugs or alcohol. On physical examination, his heart rate is 97/min. His blood pressure is 95/40 mm Hg in the right arm and 60/30 mm Hg in the left arm. Pulses are absent in the right leg and diminished in the left. A neurological examination is normal. A chest X-ray reveals a widened mediastinum. Which of the following is the most likely etiology of this patient's condition?", "answer": "Traumatic aortic dissection", "options": {"A": "Rib fracture", "B": "Traumatic aortic dissection", "C": "Myocardial rupture", "D": "Pulmonary contusion", "E": "Diaphragmatic rupture"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 23-year-old man presents to the emergency department with shortness of breath. The patient was at a lunch hosted by his employer. He started to feel his symptoms begin when he started playing football outside with a few of the other employees. The patient has a past medical history of atopic dermatitis and asthma. His temperature is 98.3°F (36.8°C), blood pressure is 87/58 mmHg, pulse is 150/min, respirations are 22/min, and oxygen saturation is 85% on room air. Which of the following is the best next step in management?", "answer": "IM epinephrine", "options": {"A": "Albuterol and norepinephrine", "B": "Albuterol and prednisone", "C": "IM epinephrine", "D": "IV epinephrine", "E": "IV fluids and 100% oxygen"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old G1P0 woman presents to her obstetrician for a prenatal visit. She is 30 weeks pregnant. She reports some fatigue and complains of urinary urgency. Prior to this pregnancy, she had no significant medical history. She takes a prenatal vitamin and folate supplements daily. Her mother has diabetes, and her brother has coronary artery disease. On physical examination, the fundal height is 25 centimeters. A fetal ultrasound shows a proportional reduction in head circumference, trunk size, and limb length. Which of the following is the most likely cause of the patient’s presentation?", "answer": "Rubella infection", "options": {"A": "Antiphospholipid syndrome", "B": "Cigarette smoking", "C": "Gestational diabetes", "D": "Pre-eclampsia", "E": "Rubella infection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 71-year-old male presents to the emergency department after having a generalized tonic-clonic seizure. His son reports that he does not have a history of seizures but has had increasing confusion and weakness over the last several weeks. An electrolyte panel reveals a sodium level of 120 mEq/L and a serum osmolality of 248 mOsm/kg. His urine is found to have a high urine osmolality. His temperature is 37° C (98.6° F), respirations are 15/min, pulse is 67/min, and blood pressure is 122/88 mm Hg. On examination he is disoriented, his pupils are round and reactive to light and accommodation and his mucous membranes are moist. His heart has a regular rhythm without murmurs, his lungs are clear to auscultation bilaterally, the abdomen is soft, and his extremities have no edema but his muscular strength is 3/5 bilaterally. There is hyporeflexia of all four extremities. What is the most likely cause of his symptoms?", "answer": "Syndrome of Inappropriate Antidiuretic Hormone (SIADH)", "options": {"A": "Syndrome of Inappropriate Antidiuretic Hormone (SIADH)", "B": "Sheehan’s syndrome", "C": "Lithium use", "D": "Diabetic ketoacidosis", "E": "Hereditary diabetes insipidus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 69-year-old woman presents with pain in her hip and groin. She states that the pain is present in the morning, and by the end of the day it is nearly unbearable. Her past medical history is notable for a treated episode of acute renal failure, diabetes mellitus, obesity, and hypertension. Her current medications include losartan, metformin, insulin, and ibuprofen. The patient recently started taking high doses of vitamin D as she believes that it could help her symptoms. She also states that she recently fell off the treadmill while exercising at the gym. On physical exam you note an obese woman. There is pain, decreased range of motion, and crepitus on physical exam of her right hip. The patient points to the areas that cause her pain stating that it is mostly over the groin. The patient's skin turgor reveals tenting. Radiography is ordered.\n\nWhich of the following is most likely to be found on radiography?", "answer": "Loss of joint space and osteophytes", "options": {"A": "Loss of joint space and osteophytes", "B": "Hyperdense foci in the ureters", "C": "Femoral neck fracture", "D": "Posterior displacement of the femoral head", "E": "Normal radiography"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 35-year-old woman presents to a physician’s office for a follow-up visit. She recently underwent a complete physical examination with routine laboratory tests. She also had a Pap smear and testing for sexually transmitted diseases. Since her divorce 2 years ago, she had sexual encounters with random men at bars or social events and frequently did not use any form of contraception during sexual intercourse. She was shown to be positive for the human immunodeficiency virus (HIV). Combination anti-retroviral treatment is initiated including zidovudine, didanosine, and efavirenz. One week later, she is rushed to the hospital where she is diagnosed with acute pancreatitis. Which of the following precautions will be required after pancreatitis resolves with treatment?", "answer": "Replace didanosine with lamivudine", "options": {"A": "Frequent monitoring of CD4+ cell count", "B": "Add ritonavir to the HIV treatment regimen", "C": "Replace efavirenz with nevirapine", "D": "Check hemoglobin levels", "E": "Replace didanosine with lamivudine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A primigravida at 10+5 weeks gestation registers in an obstetric clinic for prenatal care. She has noted a rash that is rough with red-brown spots on her palms. The rapid plasma reagin (RPR) test is positive. The diagnosis is confirmed by darkfield microscopy. What is the fetus at risk for secondary to the mother’s condition?", "answer": "Saddle nose", "options": {"A": "Seizures", "B": "Vision loss", "C": "Saddle nose", "D": "Chorioretinitis", "E": "Muscle atrophy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old woman that has recently immigrated from Southeast Asia is brought to the emergency department due to a 3-week history of fatigue, night sweats, and enlarged lymph nodes and persistent fever. These symptoms have been getting worse during the past week. She has no history of any cardiac or pulmonary disease. A chest X-ray reveals ipsilateral hilar enlargement and a rounded calcified focus near the right hilum. A Mantoux test is positive. Sputum samples are analyzed and acid-fast bacilli are identified on Ziehl-Neelsen staining. The patient is started on a 4 drug regimen. She returns after 6 months to the emergency department with complaints of joint pain, a skin rash that gets worse with sunlight and malaise. The antinuclear antibody (ANA) and anti-histone antibodies are positive. Which of the following drugs prescribed to this patient is the cause of her symptoms?", "answer": "Isoniazid", "options": {"A": "Rifampicin", "B": "Isoniazid", "C": "Pyrazinamide", "D": "Ethambutol", "E": "Streptomycin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 71-year-old African American man is brought to the emergency department with sudden onset lower limb paralysis and back pain. He has had generalized bone pain for 2 months. He has no history of severe illnesses. He takes ibuprofen for pain. On examination, he is pale. The vital signs include: temperature 37.1°C (98.8°F), pulse 68/min, respiratory rate 16/min, and blood pressure 155/90 mm Hg. The neurologic examination shows paraparesis. The 8th thoracic vertebra is tender to palpation. X-ray of the thoracic vertebrae confirms a compression fracture at the same level. The laboratory studies show the following:\nLaboratory test\nHemoglobin 9 g/dL\nMean corpuscular volume 95 μm3\nLeukocyte count 5,000/mm3\nPlatelet count 240,000/mm3\nESR 85 mm/hr\nSerum\nNa+ 135 mEq/L\nK+ 4.2 mEq/L\nCl− 113 mEq/L\nHCO3− 20 mEq/L\nCa+ 11.8 mg/dL\nAlbumin 4 g/dL\nUrea nitrogen 38 mg/dL\nCreatinine 2.2 mg/dL\nWhich of the following is the most likely mechanism underlying this patient’s vertebral fracture?", "answer": "Proliferation of tumor cells", "options": {"A": "Acidosis-induced bone lysis", "B": "Bone demineralization", "C": "Increased mechanical pressure", "D": "Increased osteoblastic activity", "E": "Proliferation of tumor cells"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old male was in a motor vehicle accident that caused him to fracture his femur and pelvis. After 2 days in the hospital, the patient became delirious, tachypneic, and a petechial rash was found in his upper extremities. Which of the following is most likely responsible for this patient’s symptoms?", "answer": "Fat microglobules in the microvasculature", "options": {"A": "Thrombotic clot in the pulmonary artery", "B": "Fat microglobules in the microvasculature", "C": "Type I and type II pneumocyte damage due to neutrophils", "D": "Aspiration of oropharyngeal contents", "E": "Alveolar foamy exudates with disc shaped cysts seen with methenamine silver stain"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old man with a 30-pack-year history comes to the physician for a follow-up examination 6 months after a chest CT showed a solitary 5-mm solid nodule in the upper lobe of the right lung. The follow-up CT shows that the size of the nodule has increased to 2 cm. Ipsilateral mediastinal lymph node involvement is noted. A biopsy of the pulmonary nodule shows small, dark blue tumor cells with hyperchromatic nuclei and scarce cytoplasm. Cranial MRI and skeletal scintigraphy show no evidence of other metastases. Which of the following is the most appropriate next step in management?", "answer": "Cisplatin-etoposide therapy and radiotherapy", "options": {"A": "Wedge resection", "B": "Radiation therapy", "C": "Cisplatin-etoposide therapy and radiotherapy", "D": "Right lobectomy", "E": "Gefitinib therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A newborn born at 33 weeks of gestation has a respiratory rate of 70/min and a heart rate of 148/min 2 hours after birth. He is grunting and has intercostal and subcostal retractions. He has peripheral cyanosis as well. An immediate chest radiograph is taken which shows a fine reticular granulation with ground glass appearance on both lungs. Which of the following is the most likely diagnosis?", "answer": "Respiratory distress syndrome", "options": {"A": "Pneumothorax", "B": "Transient tachypnea of the newborn", "C": "Respiratory distress syndrome", "D": "Cyanotic congenital heart disease", "E": "Bacterial pneumonia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A hospitalized 70-year-old woman, who recently underwent orthopedic surgery, develops severe thrombocytopenia of 40,000/mm3 during her 7th day of hospitalization. She has no other symptoms and has no relevant medical history. All of the appropriate post-surgery prophylactic measures had been taken. Her labs from the 7th day of hospitalization are shown here:\nThe complete blood count results are as follows:\nHemoglobin 13 g/dL\nHematocrit 38%\nLeukocyte count 8,000/mm3\nNeutrophils 54%\nBands 3%\nEosinophils 1%\nBasophils 0%\nLymphocytes 33%\nMonocytes 7%\nPlatelet count 40,000/mm3\nThe coagulation tests are as follows:\nPartial thromboplastin time (activated) 85 seconds\nProthrombin time 63 seconds\nReticulocyte count 1.2%\nThrombin time < 2 seconds deviation from control\nThe lab results from previous days were within normal limits. What is the most likely cause of the thrombocytopenia?", "answer": "Heparin-induced thrombocytopenia", "options": {"A": "DIC", "B": "Thrombotic microangiopathy", "C": "Immune thrombocytopenia", "D": "Myelodysplasia", "E": "Heparin-induced thrombocytopenia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 57-year-old man presents to his physician with dyspnea on exertion and rapid heartbeat. He denies any pain during these episodes. He works as a machine operator at a solar panels manufacturer. He has a 21-pack-year history of smoking. The medical history is significant for a perforated ulcer, in which he had to undergo gastric resection and bypass. He also has a history of depression, and he is currently taking escitalopram. The family history is unremarkable. The patient weighs 69 kg (152 lb). His height is 169 cm (5 ft 7 in). The vital signs include: blood pressure 140/90 mm Hg, heart rate 95/min, respiratory rate 12/min, and temperature 36.6℃ (97.9℉). Lung auscultation reveals widespread wheezes. Cardiac auscultation shows decreased S1 and grade 1/6 midsystolic murmur best heard at the apex. Abdominal and neurological examinations show no abnormalities. A subsequent echocardiogram shows increased left ventricular mass and an ejection fraction of 50%. Which of the options is a risk factor for the condition detected in the patient?", "answer": "Smoking", "options": {"A": "The patient’s body mass", "B": "History of gastric bypass surgery", "C": "Exposure to heavy metals", "D": "Smoking", "E": "Escitalopram intake"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old man presents to the emergency department with bilateral eye pain. The patient states it has slowly been worsening over the past 48 hours. He admits to going out this past weekend and drinking large amounts of alcohol and having unprotected sex but cannot recall a predisposing event. The patient's vitals are within normal limits. Physical exam is notable for bilateral painful and red eyes with opacification and ulceration of each cornea. The patient's contact lenses are removed and a slit lamp exam is performed and shows bilateral corneal ulceration. Which of the following is the best treatment for this patient?", "answer": "Gatifloxacin eye drops", "options": {"A": "Acyclovir", "B": "Erythromycin ointment", "C": "Gatifloxacin eye drops", "D": "Intravitreal vancomycin and ceftazidime", "E": "Topical dexamethasone and refrain from wearing contacts"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 73-year-old man is brought in by his wife with a history of progressive personality changes. The patient’s wife says that, over the past 3 years, he has become increasingly aggressive and easily agitated, which is extremely out of character for him. His wife also says that he has had several episodes of urinary incontinence in the past month. He has no significant past medical history. The patient denies any history of smoking, alcohol use, or recreational drug use. The patient is afebrile, and his vital signs are within normal limits. A physical examination is unremarkable. The patient takes the mini-mental status examination (MMSE) and scores 28/30. A T2 magnetic resonance image (MRI) of the head is performed and the results are shown in the exhibit (see image). Which of the following is the next best diagnostic step in the management of this patient?", "answer": "Lumbar puncture", "options": {"A": "Noncontrast CT of the head", "B": "Contrast MRI of the head", "C": "Lumbar puncture", "D": "Brain biopsy", "E": "Serum ceruloplasmin level"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old woman presents to the emergency department with palpitations, sweating, and blurry vision after playing volleyball on the beach. She denies chest pain and shortness of breath. She states that these episodes occur often, but resolve after eating a meal or drinking a sugary soda. Past medical history is unremarkable, and she takes no medications. Temperature is 37°C (98.6°F), blood pressure is 135/80 mm Hg, pulse is 102/min, and respirations are 18/min. Fingerstick blood glucose level is 42 g/dL. ECG reveals sinus tachycardia. Urinalysis and toxicology are noncontributory. Appropriate medical therapy is administered and she is discharged with an appointment for a fasting blood draw within the week. Laboratory results are as follows:\nBlood glucose 45 mg/dL\nSerum insulin  20 microU/L (N: < 6 microU/L)\nSerum proinsulin 10 microU/L (N: < 20% of total insulin)\nC-peptide level  0.8 nmol/L (N: < 0.2 nmol/L)\nSulfonylurea Negative\nIGF-2  Negative\nWhat is the most likely cause of this patient’s hypoglycemia?", "answer": "Beta cell tumor of the pancreas", "options": {"A": "Heat stroke", "B": "Delta cell tumor of the pancreas", "C": "Exogenous insulin", "D": "Beta cell tumor of the pancreas", "E": "Alpha cell tumor of the pancreas"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 12-month-old boy is brought in by his mother who is worried about pallor. She says that the patient has always been fair-skinned, but over the past month relatives have commented that he appears more pale. The mother says that the patient seems to tire easy, but plays well with his older brother and has even started to walk. She denies bloody or black stools, easy bruising, or excess bleeding. She states that he is a picky eater, but he loves crackers and whole milk. On physical examination, pallor of the conjunctiva is noted. There is a grade II systolic ejection murmur best heard over the lower left sternal border that increases when the patient is supine. Labs are drawn as shown below:\n\nLeukocyte count: 6,500/mm^3 with normal differential\nHemoglobin: 6.4 g/dL\nPlatelet count: 300,000/mm^3\nMean corpuscular volume (MCV): 71 µm^3\nReticulocyte count: 2.0%\n\nSerum iron: 34 mcg/dL\nSerum ferritin: 6 ng/mL (normal range 7 to 140 ng/mL)\nTotal iron binding capacity (TIBC): 565 mcg/dL (normal range 240 to 450 mcg/dL)\n\nOn peripheral blood smear, there is microcytosis, hypochromia, and mild anisocytosis without basophilic stippling. Which of the following is the next best step in management for the patient’s diagnosis?", "answer": "Limit milk intake", "options": {"A": "Administer deferoxamine", "B": "Echocardiogram", "C": "Limit milk intake", "D": "Measure folate level", "E": "Measure lead level"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old man presents to the emergency department with a chief complaint of ringing in his ears that started several hours previously that has progressed to confusion. The patient denies any history of medical problems except for bilateral knee arthritis. He was recently seen by an orthopedic surgeon to evaluate his bilateral knee arthritis but has opted to not undergo knee replacement and prefers medical management. His wife noted that prior to them going on a hike today, he seemed confused and not himself. They decided to stay home, and roughly 14 hours later, he was no longer making any sense. Physical exam is notable for a confused man. The patient's vitals are being performed and his labs are being drawn. Which of the following is most likely to be seen on blood gas analysis?", "answer": "pH: 7.30, PaCO2: 15 mmHg, HCO3-: 16 mEq/L", "options": {"A": "pH: 7.30, PaCO2: 15 mmHg, HCO3-: 16 mEq/L", "B": "pH: 7.31, PaCO2: 31 mmHg, HCO3-: 15 mEq/L", "C": "pH: 7.37, PaCO2: 41 mmHg, HCO3-: 12 mEq/L", "D": "pH: 7.41, PaCO2: 65 mmHg, HCO3-: 34 mEq/L", "E": "pH: 7.47, PaCO2: 11 mmHg, HCO3-: 24 mEq/L"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 56-year-old woman is referred to your office with mammography results showing a dense, spiculated mass with clustered microcalcifications. The family history is negative for breast, endometrial, and ovarian cancers. She was formerly a flight attendant and since retirement, she has started a strict Mediterranean diet because she was \"trying to compensate for her lack of physical activity\". She is the mother of two. She breastfed each infant for 18 months, as recommended by her previous physician. Her only two surgical procedures have been a breast augmentation with implants and tubal ligation. The physical examination is unremarkable. There are no palpable masses and no nipple or breast skin abnormalities. The patient lacks a family history of breast cancer. Which of the following is the most significant risk factor for the development of breast cancer in this patient?", "answer": "Occupation", "options": {"A": "Sedentarism", "B": "Breastfeeding", "C": "Mediterranean diet", "D": "Breast implants", "E": "Occupation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman is brought to the emergency department after an episode of syncope. For the past 10 days, she has had dyspnea and palpitations occurring with mild exertion. The patient returned from a hiking trip in Upstate New York 5 weeks ago. Except for an episode of flu with fever and chills a month ago, she has no history of serious illness. Her temperature is 37.3°C (99.1°F), pulse is 45/min, respirations are 21/min, and blood pressure is 148/72 mm Hg. A resting ECG is shown. Two-step serological testing confirms the diagnosis. Which of the following is the most appropriate treatment?", "answer": "Intravenous ceftriaxone", "options": {"A": "Intravenous ceftriaxone", "B": "Beta blocker", "C": "Oral doxycycline", "D": "Atropine", "E": "Permanent pacemaker implantation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 64-year-old male presents to his primary care physician. Laboratory work-up and physical examination are suggestive of a diagnosis of prostatic adenocarcinoma. A tissue biopsy is obtained, which confirms the diagnosis. Which of the following is indicative of metastatic disease?", "answer": "New-onset lower back pain", "options": {"A": "Decreased serum alkaline phosphatase", "B": "Elevated prostatic acid phosphatase (PAP)", "C": "Involvement of the periurethral zone", "D": "New-onset lower back pain", "E": "Palpation of a hard nodule on digital rectal examination"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A patient with a known spinal cord ependymoma presents to his neurologist for a check up. He complains that he has had difficulty walking, which he attributes to left leg weakness. On exam, he is noted to have 1/5 strength in his left lower extremity, as well as decreased vibration and position sensation in the left lower extremity and decreased pain and temperature sensation in the right lower extremity. Which of the following spinal cord lesions is most consistent with his presentation?", "answer": "Left-sided Brown-Sequard (hemisection)", "options": {"A": "Left-sided Brown-Sequard (hemisection)", "B": "Right-sided Brown-Sequard (hemisection)", "C": "Anterior cord syndrome", "D": "Posterior cord syndrome", "E": "Syringomelia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2500-g (5-lb 8-oz) female newborn delivered at 37 weeks' gestation develops rapid breathing, grunting, and subcostal retractions shortly after birth. Despite appropriate lifesaving measures, the newborn dies 2 hours later. Autopsy shows bilateral renal agenesis. Which of the following is the most likely underlying cause of this newborn's respiratory distress?", "answer": "Decreased amniotic fluid ingestion", "options": {"A": "Decreased amniotic fluid ingestion", "B": "Injury to the diaphragmatic innervation", "C": "Displacement of intestines into the pleural cavity", "D": "Collapse of the supraglottic airway", "E": "Surfactant inactivation and epithelial inflammation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 53-year-old man comes to the physician for recurring fever and night sweats for the past 6 months. The fevers persist for 7 to 10 days and then subside completely for about a week before returning again. During this period, he has also noticed two painless lumps on his neck that have gradually increased in size. Over the past year, he has had an 8.2-kg (18.1 lbs) weight loss. Two years ago, he had a severe sore throat and fever, which was diagnosed as infectious mononucleosis. He has smoked a pack of cigarettes daily for the past 10 years. He does not drink alcohol. His job involves monthly international travel to Asia and Africa. He takes no medications. His temperature is 39°C (102.2°F), pulse is 90/min, respirations are 22/min, and blood pressure is 105/60 mm Hg. Physical examination shows 2 enlarged, nontender, fixed cervical lymph nodes on each side of the neck. Microscopic examination of a specimen obtained on biopsy of a cervical lymph node is shown. Which of the following additional findings is most likely present in this patient?", "answer": "CD15/30 positive cells", "options": {"A": "Anti-viral capsid antigen IgG and IgM positive", "B": "CD15/30 positive cells", "C": "Auer rods on peripheral smear", "D": "Leukocyte count > 500,000/μL", "E": "Acid fast bacilli in the sputum"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 17-year-old male presents with altered mental status. He was recently admitted to the hospital due to a tibial fracture suffered while playing soccer. His nurse states that he is difficult to arouse. His temperature is 98.6 deg F (37 deg C), blood pressure is 130/80 mm Hg, pulse is 60/min, and respirations are 6/min. Exam is notable for pinpoint pupils and significant lethargy. Which of the following describes the mechanism of action of the drug likely causing this patient's altered mental status?", "answer": "Neuronal hyperpolarization due to potassium efflux", "options": {"A": "Neuronal hyperpolarization due to potassium efflux", "B": "Neuronal depolarization due to potassium influx", "C": "Neuronal hyperpolarization due to sodium influx", "D": "Neuronal depolarization due to sodium efflux", "E": "Neuronal hyperpolarization due to chloride influx"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old boy is brought to the emergency department because of sudden-onset abdominal pain that began 1 hour ago. Three days ago, he was diagnosed with a urinary tract infection and was treated with nitrofurantoin. There is no personal history of serious illness. His parents emigrated from Kenya before he was born. Examination shows diffuse abdominal tenderness, mild splenomegaly, and scleral icterus. Laboratory studies show:\nHemoglobin 9.8 g/dL\nMean corpuscular volume 88 μm3\nReticulocyte count 3.1%\nSerum\nBilirubin\nTotal 3.8 mg/dL\nDirect 0.6 mg/dL\nHaptoglobin 16 mg/dL (N=41–165 mg/dL)\nLactate dehydrogenase 179 U/L\nWhich of the following is the most likely underlying cause of this patient's symptoms?\"", "answer": "Enzyme deficiency in red blood cells", "options": {"A": "Enzyme deficiency in red blood cells", "B": "Defective red blood cell membrane proteins", "C": "Defect in orotic acid metabolism", "D": "Lead poisoning", "E": "Absent hemoglobin beta chain"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man comes to the physician with chills, nausea, and diffuse muscle aches for 3 days. His niece had similar symptoms 2 weeks ago and H1N1 influenza strain was isolated from her respiratory secretions. He received his influenza vaccination 2 months ago. His temperature is 38°C (100.4°F). A rapid influenza test is positive. Which of the following mechanisms best explains this patient's infection despite vaccination?", "answer": "Random point mutations within viral genome", "options": {"A": "Random point mutations within viral genome", "B": "Complementing with functional viral proteins", "C": "Exchange of viral genes between chromosomes", "D": "Reassortment of viral genome segments", "E": "Acquisition of viral surface proteins"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old G1P0 woman gives birth to a male infant at 35 weeks gestation. The child demonstrates a strong cry and moves all his arms and legs upon birth. Respirations are slow and irregular. His temperature is 99.1°F (37.3°C), blood pressure is 100/55 mmHg, pulse is 115/min, and respirations are 18/min. At a follow up appointment, the physician notices that the infant’s torso and upper extremities are pink while his lower extremities have a bluish hue. Which of the following will most likely be heard on auscultation of the patient’s chest?", "answer": "Continuous systolic and diastolic murmur at left upper sternal border", "options": {"A": "Rumbling noise in late diastole", "B": "Early diastolic decrescendo murmur at the left sternal border", "C": "Holosystolic murmur radiating to the right sternal border", "D": "Holosystolic murmur radiating to the axilla", "E": "Continuous systolic and diastolic murmur at left upper sternal border"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Blood cultures are sent to the laboratory. Intravenous antibiotic therapy is started. Transesophageal echocardiography shows a large, oscillating vegetation attached to the tricuspid valve. There are multiple small vegetations attached to tips of the tricuspid valve leaflets. There is moderate tricuspid regurgitation. The left side of the heart and the ejection fraction are normal. Which of the following is the most likely causal organism of this patient's conditions?", "answer": "Staphylococcus aureus", "options": {"A": "Streptococcus sanguinis", "B": "Enterococcus faecalis", "C": "Staphylococcus epidermidis", "D": "Neisseria gonorrhoeae", "E": "Staphylococcus aureus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 59-year-old male presents to the emergency room complaining of substernal chest pain. He reports a three-hour history of dull substernal chest pain that radiates into his left arm and jaw. He has experienced similar chest pain before that was brought on with exertion, but this pain is more severe and occurred with rest. His past medical history includes gout, hypertension, diabetes mellitus, and hyperlipidemia. An EKG demonstrates ST segment depression. Serum troponin is elevated. In addition to aspirin, oxygen, and morphine, he is started on a sublingual medication. What is the main physiologic effect of this medication?", "answer": "Decrease preload", "options": {"A": "Decrease preload", "B": "Increase preload", "C": "Decrease afterload", "D": "Increase contractility", "E": "Decrease heart rate"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-day-old male newborn is brought to the physician by his mother for the evaluation of yellowing of his skin and eyes for one day. The mother reports that she is breastfeeding her son about 7 times per day. She also states that her son had two wet diapers and two bowel movements yesterday. He was born at 38 weeks' gestation and weighed 3500 g (7.7 lb); he currently weighs 3000 g (6.6 lb). His newborn screening was normal. His temperature is 37°C (98.6°F), pulse is 180/min, and blood pressure is 75/45 mm Hg. Physical examination shows scleral icterus, widespread jaundice, and dry mucous membranes. The remainder of the examination shows no abnormalities. Serum studies show:\nBilirubin\nTotal 9 mg/dL\nDirect 0.7 mg/dL\nAST 15 U/L\nALT 15 U/L\nWhich of the following is the most appropriate next step in the management of this patient?\"", "answer": "Increasing frequency of breastfeeding", "options": {"A": "Intravenous immunoglobulin", "B": "Phenobarbital", "C": "Increasing frequency of breastfeeding", "D": "Abdominal sonography", "E": "Phototherapy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old woman is rushed to the emergency department after she was found unconscious in a house fire. She has no previous medical history available. At the hospital, the vital signs include: blood pressure 110/70 mm Hg, temperature 36.0°C (97.0°F), and heart rate 76/min with oxygen saturation 99% on room air. On physical exam she is unconscious. There are superficial burns on her hands and parts of her face. Her face and clothes are blackened with soot. What is the 1st best step while treating this patient?", "answer": "Administer 100% oxygen", "options": {"A": "Penicillamine", "B": "Sodium nitrite", "C": "Administer 100% oxygen", "D": "Pyridoxine (vitamin B6)", "E": "N-acetylcysteine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 39-year-old woman is brought to the emergency department in a semi-unconscious state by her neighbor who saw her lose consciousness. There was no apparent injury on the primary survey. She is not currently taking any medications. She has had loose stools for the past 3 days and a decreased frequency of urination. No further history could be obtained. The vital signs include: blood pressure 94/62 mm Hg, temperature 36.7°C (98.0°F), pulse 105/min, and respiratory rate 10/min. The skin appears dry. Routine basic metabolic panel, urine analysis, urine osmolality, and urine electrolytes are pending. Which of the following lab abnormalities would be expected in this patient?", "answer": "Serum blood urea nitrogen/creatinine (BUN/Cr) > 20", "options": {"A": "Urine osmolality < 350 mOsm/kg", "B": "Urine Na+ > 40 mEq/L", "C": "Fractional excretion of sodium (FENa) > 2%", "D": "Serum blood urea nitrogen/creatinine (BUN/Cr) > 20", "E": "Serum creatinine < 1 mg/dL"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man is brought to the emergency department following a house fire. Following initial stabilization, the patient is transferred to the ICU for management of his third-degree burn injuries. On the second day of hospitalization, a routine laboratory panel is obtained, and the results are demonstrated below. Per the nurse, he remains stable compared to the day prior. His temperature is 99°F (37°C), blood pressure is 92/64 mmHg, pulse is 98/min, respirations are 14/min, and SpO2 is 98%. A physical examination demonstrates an unresponsive patient with extensive burn injuries throughout his torso and lower extremities.\n\nHemoglobin: 13 g/dL\nHematocrit: 36%\nLeukocyte count: 10,670/mm^3 with normal differential\nPlatelet count: 180,000/mm^3\n\nSerum:\nNa+: 135 mEq/L\nCl-: 98 mEq/L\nK+: 4.7 mEq/L\nHCO3-: 25 mEq/L \nBUN: 10 mg/dL \nGlucose: 123 mg/dL\nCreatinine: 1.8 mg/dL\nThyroid-stimulating hormone: 4.3 µU/mL\nTriiodothyronine: 48 ng/dL\nThyroxine: 10 ug/dL\nCa2+:  8.7 mg/dL\nAST: 89 U/L\nALT: 135 U/L\n\nWhat is the best course of management for this patient?", "answer": "Continued management of his burn wounds", "options": {"A": "Continued management of his burn wounds", "B": "Immediate administration of propanolol", "C": "Increase opioid dosage", "D": "Regular levothyroxine sodium injections", "E": "Start patient on intravenous ceftriaxone and vancomycin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old boy comes to the physician because of fever, fatigue, and a sore throat for 12 days. He was prescribed amoxicillin at another clinic and now has a diffuse rash all over his body. He was treated for gonorrhea one year ago. He has multiple sexual partners and uses condoms inconsistently. He appears lethargic and thin. His BMI is 19.0 kg/m2. His temperature is 38.4°C (101.1°F), pulse 94/min, blood pressure 106/72 mm Hg. Examination shows a morbilliform rash over his extremities. Oropharyngeal examination shows tonsillar enlargement and erythema with exudates. Tender cervical and inguinal lymphadenopathy is present. Abdominal examination shows mild splenomegaly. Laboratory studies show:\nHemoglobin 14 g/dL\nLeukocyte count 13,200/mm3\nPlatelet count 160,000/mm3\nWhich of the following is the next best step in management?\"", "answer": "Heterophile agglutination test", "options": {"A": "Throat swab culture", "B": "Anti-CMV IgM", "C": "ELISA for HIV", "D": "Heterophile agglutination test", "E": "Flow cytometry"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 71-year-old man presents to the primary care clinic with non-specific complaints of fatigue and malaise. His past medical history is significant for diabetes mellitus type II, hypertension, non-seminomatous testicular cancer, and hypercholesterolemia. He currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and he currently denies any illicit drug use. His vital signs include: temperature, 36.7°C (98.0°F); blood pressure, 126/74 mm Hg; heart rate, 87/min; and respiratory rate, 17/min. On examination, his physician notices cervical and inguinal lymphadenopathy bilaterally, as well as splenomegaly. The patient comments that he has lost 18.1 kg (40 lb) over the past 6 months without a change in diet or exercise, which he was initially not concerned about. The physician orders a complete blood count and adds on flow cytometry. Based on his age and overall epidemiology, which of the following is the most likely diagnosis?", "answer": "Chronic lymphocytic leukemia", "options": {"A": "Acute lymphocytic leukemia", "B": "Acute myelogenous leukemia", "C": "Chronic lymphocytic leukemia", "D": "Chronic myelogenous leukemia", "E": "Hairy cell leukemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 69-year-old man comes to his cardiologist for a follow-up visit. He is being considered for a new drug therapy that works by modulating certain proteins released from the heart in patients with heart failure. A drug called candoxatril is being investigated for its ability to inhibit the action of an endopeptidase that breaks down a vasodilatory mediator released from the heart, as well as, endothelin and bradykinin. This mediator is known to promote the excretion of sodium from the body and improve the ejection fraction. One of its side effects is its ability to increase angiotensin II levels which causes harm to patients with heart failure. Therefore, to improve efficacy and reduce its adverse effects, candoxatril has to be used in conjunction with angiotensin receptor blockers. Which of the following is most likely to increase as a result of this drug regimen?", "answer": "Natriuretic peptides", "options": {"A": "Thromboxane", "B": "Nitric oxide", "C": "Leukotrienes", "D": "Acetylcholine", "E": "Natriuretic peptides"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Seventy-two hours after admission for an acute myocardial infarction, a 48-year-old man develops dyspnea and a productive cough with frothy sputum. Physical examination shows coarse crackles in both lungs and a blowing, holosystolic murmur heard best at the apex. ECG shows Q waves in the anteroseptal leads. Pulmonary capillary wedge pressure is 23 mm Hg. Which of the following is the most likely cause of this patient’s current condition?", "answer": "Rupture of the chordae tendinae", "options": {"A": "Postmyocardial infarction syndrome", "B": "Aortic root dilation", "C": "Rupture of the chordae tendinae", "D": "Rupture of the ventricular free wall", "E": "Rupture of the interventricular septum"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old man comes to the physician because of a productive cough and dyspnea. He has smoked one pack of cigarettes daily for 15 years. His temperature is 38.8°C (102°F). Physical examination shows decreased breath sounds and dullness on percussion above the right lower lobe. An x-ray of the chest shows a right lower lobe density and a small amount of fluid in the right pleural space. The patient's symptoms improve with antibiotic treatment, but he develops right-sided chest pain one week later. Pulmonary examination shows new scratchy, high-pitched breath sounds on auscultation of the right lobe. Histologic examination of a pleural biopsy specimen is most likely to show which of the following findings?", "answer": "Fibrin-rich infiltrate", "options": {"A": "Cholesterol-rich infiltrate", "B": "Fibrin-rich infiltrate", "C": "Dense bacterial infiltrate", "D": "Epithelioid infiltrate with central necrosis", "E": "Red blood cell infiltrate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 50-year-old obese woman presents for a follow-up appointment regarding microcalcifications found in her left breast on a recent screening mammogram. The patient denies any recent associated symptoms. The past medical history is significant for polycystic ovarian syndrome (PCOS), for which she takes metformin. Her menarche occurred at age 11, and the patient still has regular menstrual cycles. The family history is significant for breast cancer in her mother at the age of 72. The review of systems is notable for a 6.8 kg (15 lb) weight loss in the past 2 months. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 130/70 mm Hg, pulse 82/min, respiratory rate 17/min, and oxygen saturation 98% on room air. On physical examination, the patient is alert and cooperative. The breast examination reveals no palpable masses, lymphadenopathy, or evidence of skin retraction. An excisional biopsy of the left breast is performed, and histologic examination demonstrates evidence of non-invasive malignancy. Which of the following is the most appropriate course of treatment for this patient?", "answer": "Lumpectomy", "options": {"A": "Observation with bilateral mammograms every 6 months", "B": "Tamoxifen", "C": "Radiotherapy", "D": "Lumpectomy", "E": "Bilateral mastectomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 18-month-old boy presents to the clinic with his mother for evaluation of a rash around the eyes and mouth. His mother states that the rash appeared 2 weeks ago and seems to be very itchy because the boy scratches his eyes often. The patient is up to date on all of his vaccinations and is meeting all developmental milestones. He has a history of asthma that was recently diagnosed. On examination, the patient is playful and alert. He has scaly, erythematous skin surrounding both eyes and his mouth. Bilateral pupils are equal and reactive to light and accommodation, and conjunctiva is clear, with no evidence of jaundice or exudates. The pharynx and oral mucosa are within normal limits, and no lesions are present. Expiratory wheezes can be heard in the lower lung fields bilaterally. What is this most likely diagnosis in this patient?", "answer": "Atopic dermatitis", "options": {"A": "Viral conjunctivitis", "B": "Bronchiolitis", "C": "Impetigo", "D": "Atopic dermatitis", "E": "Scalded skin syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 63-year-old man presents to the emergency department with periorbital swelling. He states that he was gardening, came inside, looked in the mirror, and then noticed his eyelids were swollen. He denies pain, pruritus, or visual disturbances. He states that he was drinking “a lot of water\" to prevent dehydration, because it was hot outside this morning. His medical history is significant for rheumatoid arthritis. He takes methotrexate and acetaminophen as needed. The patient’s temperature is 98°F (36.7°C), blood pressure is 168/108 mmHg, and pulse is 75/min. Physical examination is notable for periorbital edema, hepatomegaly, and bilateral 1+ pitting lower extremity edema. Labs and a urinalysis are obtained, as shown below:\n\nLeukocyte count: 11,000/mm^3\nHemoglobin: 14 g/dL\n\nSerum:\nNa: 138 mEq/L\nK+: 4.3 mEq/L\nCl-: 104 mEq/L\nHCO3-: 25 mEq/L\nUrea nitrogen: 26 mg/dL\nCreatinine: 1.4 mg/dL\nGlucose: 85 mg/dL\nAspartate aminotransferase (AST, GOT): 15 U/L\nAlanine aminotransferase (ALT, GPT): 19 U/L\nAlbumin: 2.0 g/dL\n\nUrine:\nProtein: 150 mg/dL\nCreatinine: 35 mg/dL\n\nAn abdominal ultrasound reveals an enlarged liver with heterogeneous echogenicity and enlarged kidneys with increased echogenicity in the renal parenchyma. A biopsy of the kidney is obtained. Which of the following biopsy findings is associated with the patient’s most likely diagnosis?", "answer": "Apple green birefringence with Congo red staining", "options": {"A": "Apple green birefringence with Congo red staining", "B": "Glomerular basement membrane splitting", "C": "Kimmelstiel-Wilson nodules", "D": "Subepithelial dense deposits", "E": "Tubulointerstitial fibrosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 68-year-old woman presents to her primary care physician for a regular check-up. She complains of swelling of her legs and face, which is worse in the morning and decreases during the day. She was diagnosed with type 2 diabetes mellitus a year ago and prescribed metformin, but she has not been compliant with it preferring ‘natural remedies’ over the medications. She does not have a history of cardiovascular disease or malignancy. Her vital signs are as follows: blood pressure measured on the right hand is 130/85 mm Hg, on the left hand, is 110/80 mm Hg, heart rate is 79/min, respiratory rate is 16/min, and the temperature is 36.6℃ (97.9°F). Physical examination reveals S1 accentuation best heard in the second intercostal space at the right sternal border. Facial and lower limbs edema are evident. The results of the laboratory tests are shown in the table below.\nFasting plasma glucose  164 mg/dL\nHbA1c 10.4%\nTotal cholesterol 243.2 mg/dL\nTriglycerides 194.7 mg/dL\nCreatinine 1.8 mg/dL\nUrea nitrogen 22.4 mg/dL\nCa2+ 9.6 mg/dL\nPO42- 38.4 mg/dL\nWhich of the following statements best describes this patient’s condition?", "answer": "If measured in this patient, there would be an increased PTH level.", "options": {"A": "If measured in this patient, there would be an increased PTH level.", "B": "The calcitriol level is unlikely to be affected in this patient.", "C": "Hypoparathyroidism is most likely the cause of the patient’s altered laboratory results.", "D": "Increase in 1α, 25(OH)2D3 production is likely to contribute to alteration of the patient’s laboratory values.", "E": "There is an error in Ca2+ measurement because the level of serum calcium is always decreased in the patient’s condition."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An otherwise healthy 27-year-old man presents to the Emergency Department with dark urine and left flank pain. He has had a fever, sore throat, and malaise for the last 2 days. Vital signs reveal a temperature of 38.1°C (100.5°F), blood pressure of 120/82 mm Hg, and a pulse of 95/min. His family history is noncontributory. Physical examination reveals enlarged tonsils with tender anterior cervical lymphadenopathy. Urinalysis shows pink urine with 20–25 red cells/high power field and 2+ protein. This patient’s condition is most likely due to which of the following?", "answer": "Diffuse mesangial IgA deposition", "options": {"A": "Inherited abnormalities in type IV collagen", "B": "Autoantibodies against alpha-3 chain of type IV collagen", "C": "C3 nephritic factor", "D": "Immune complex deposition", "E": "Diffuse mesangial IgA deposition"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 70-year-old man is brought to the emergency department with complaints of chest pain for the last 2 hours. He had been discharged from the hospital 10 days ago when he was admitted for acute myocardial infarction. It was successfully treated with percutaneous coronary intervention. During the physical exam, the patient prefers to hunch forwards as this decreases his chest pain. He says the pain is in the middle of the chest and radiates to his back. Despite feeling unwell, the patient denies any palpitations or shortness of breath. Vitals signs include: pulse 90/min, respiratory rate 20/min, blood pressure 134/82 mm Hg, and temperature 36.8°C (98.2°F). The patient is visibly distressed and is taking shallow breaths because deeper breaths worsen his chest pain. An ECG shows diffuse ST elevations. Which of the following should be administered to this patient?", "answer": "Ibuprofen", "options": {"A": "Ibuprofen", "B": "Heparin", "C": "Levofloxacin", "D": "Propranolol", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old female presents to her primary care physician complaining of a mass in her mid-thigh. The mass has grown slowly over the past six months and is not painful. The patient’s past medical history is notable for hypertension and hyperlipidemia. She takes lisinopril and rosuvastatin. On examination, there is a firm, immobile mass on the medial aspect of the distal thigh. She has full range of motion and strength in her lower extremities and patellar reflexes are 2+ bilaterally. A biopsy of the mass reveals multiple pleomorphic smooth muscle cells with nuclear atypia. The patient subsequently initiates radiation therapy with plans to undergo surgical resection. This tumor will most strongly stain for which of the following?", "answer": "Desmin", "options": {"A": "Chromogranin", "B": "Desmin", "C": "Cytokeratin", "D": "Glial fibrillary acidic protein", "E": "Neurofilament"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old woman presents to the emergency department for fever and generalized malaise. Her symptoms began approximately 3 days ago, when she noticed pain with urination and mild blood in her urine. Earlier this morning she experienced chills, flank pain, and mild nausea. Approximately 1 month ago she had the \"flu\" that was rhinovirus positive and was treated with supportive management. She has a past medical history of asthma. She is currently sexually active and uses contraception inconsistently. She occasionally drinks alcohol and denies illicit drug use. Family history is significant for her mother having systemic lupus erythematosus. Her temperature is 101°F (38.3°C), blood pressure is 125/87 mmHg, pulse is 101/min, and respirations are 18/min. On physical examination, she appears uncomfortable. There is left-sided flank, suprapubic, and costovertebral angle tenderness. Urine studies are obtained and a urinalysis is demonstrated below:\n\nColor: Amber\npH: 6.8\nLeukocyte: Positive\nProtein: Trace\nGlucose: Negative\nKetones: Negative\nBlood: Positive\nNitrite: Positive\nLeukocyte esterase: Positive\nSpecific gravity: 1.015\n\nIf a renal biopsy is performed in this patient, which of the following would most likely be found on pathology?", "answer": "Suppurative inflammation with interstitial neutrophilic infiltration", "options": {"A": "Diffuse capillary and glomerular basement membrane thickening", "B": "Focal and segmental sclerosis of the glomeruli and mesangium", "C": "Mesangial proliferation", "D": "Normal appearing glomeruli", "E": "Suppurative inflammation with interstitial neutrophilic infiltration"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old man, who was previously healthy, is taken to the emergency department due to agitation during the past 24 hours. During the past week, his family members noticed a yellowish coloring of his skin and eyes. He occasionally uses cocaine and ecstasy, and he drinks alcohol (about 20 g) on weekends. The patient also admits to high-risk sexual behavior and does not use appropriate protection. Physical examination shows heart rate of 94/min, respiratory rate of 13/min, temperature of 37.0°C (98.6°F), and blood pressure of 110/60 mm Hg. The patient shows psychomotor agitation, and he is not oriented to time and space. Other findings include asterixis, jaundice on the skin and mucous membranes, and epistaxis. The rest of the physical examination is normal. The laboratory tests show:\nHemoglobin 16.3 g/dL\nHematocrit 47%\nLeukocyte count 9,750/mm3\nNeutrophils 58%\nBands 2%\nEosinophils 1%\nBasophils 0%\nLymphocytes 24%\nMonocytes 2%\nPlatelet count 365,000/mm3\nBilirubin 25 mg/dL\nAST 600 IU/L\nALT 650 IU/L\nTP activity < 40%\nINR 1,5\nWhat is the most likely diagnosis?", "answer": "Fulminant hepatic failure", "options": {"A": "Hemolytic uremic syndrome", "B": "Alcoholic hepatitis", "C": "Fulminant hepatic failure", "D": "Ecstasy intoxication", "E": "Cocaine-abstinence syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 31-year-old woman is brought to the physician because of increasing restlessness over the past 2 weeks. She reports that she continuously paces around the house and is unable to sit still for more than 10 minutes at a time. During this period, she has had multiple episodes of anxiety with chest tightness and shortness of breath. She was diagnosed with a psychotic illness 2 months ago. Her current medications include haloperidol and a multivitamin. She appears agitated. Vital signs are within normal limits. Physical examination shows no abnormalities. The examination was interrupted multiple times when she became restless and began to walk around the room. To reduce the likelihood of the patient developing her current symptoms, a drug with which of the following mechanisms of action should have been prescribed instead of her current medication?", "answer": "5-HT2Areceptor antagonism", "options": {"A": "H2 receptor antagonism", "B": "NMDA receptor antagonism", "C": "GABA receptor antagonism", "D": "5-HT2Areceptor antagonism", "E": "α2 receptor antagonism"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man presents to the emergency department with shortness of breath on exertion and fatigue. He says that his symptoms onset gradually 5 days ago and have progressively worsened. Past medical history is significant for chronic alcoholism. His vital signs are blood pressure 100/60 mm Hg, temperature 36.9°C (98.4°F), respiratory rate 18/min, and pulse 98/min. On physical examination, there is bilateral pedal edema and decreased sensation in both feet. Basal crackles and rhonchi are heard on pulmonary auscultation bilaterally. Cardiac exam is unremarkable. A chest radiograph shows a maximal horizontal cardiac diameter to a maximal horizontal thoracic ratio of 0.7. A deficiency of which of the following vitamins is most likely responsible for this patient’s condition?\n ", "answer": "Thiamine", "options": {"A": "Thiamine", "B": "Riboflavin", "C": "Vitamin C", "D": "Niacin", "E": "Folic acid"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old woman sought evaluation at an urgent care clinic after developing breathlessness 30 minutes earlier. She also developed swelling of the tongue and lips. She has heart failure and was recently diagnosed with hypertension. She was started on a medication, the first dose of which she took this afternoon before her symptoms started. Her blood pressure is 167/88 mm Hg, the respiratory rate is 17/min, and the pulse is 78/min. The physical examination reveals a skin rash on the back and abdomen. There is a mild swelling of the lips and tongue. Chest auscultation does not reveal any abnormal breath sounds. Which of the following medications most likely led to her current symptoms?", "answer": "Captopril", "options": {"A": "Captopril", "B": "Amlodipine", "C": "Clonidine", "D": "Hydrochlorothiazide (HCTZ)", "E": "Propranolol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 30-year-old woman presents for pregnancy counseling. She says she has a 8 week history of chronic diarrhea. She is also found to be intolerant to heat and has been significantly losing her hair. She denies any recent changes to her diet. The patient is afebrile and her vital signs are within normal limits. Her weight today is 45.0 kg (99.2 lb) which is 4.5 kg (10 lb) less than her weight during her last visit 2 months back. On physical examination, the patient is anxious and has a non-intention tremor. Significant exophthalmos is present. Laboratory findings are significant for a low TSH, elevated free T4 and free T3, and a positive thyroid stimulating immunoglobulin assay. She still wants to conceive a baby and asks for an appropriate treatment that is safe in pregnancy. Which of the following best describes the therapy she will most likely receive during her pregnancy for her thyroid disorder?", "answer": "Thyroid peroxidase inhibitors", "options": {"A": "Thyroidectomy and thyroid replacement", "B": "Beta-blockers", "C": "Radiation", "D": "Thyroid peroxidase inhibitors", "E": "Plasmapheresis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man was shown to have a blood pressure of 142/90 mm Hg at a health fair. Despite modifying his lifestyle, his blood pressure remained elevated on 2  separate subsequent occasions. He was prescribed an anti-hypertensive medication. After 3 weeks, the swelling of the lips shown in the accompanying photograph was observed. What is the most likely cause of this finding?", "answer": "Lisinopril", "options": {"A": "Verapamil", "B": "Amlodipine", "C": "Lisinopril", "D": "Hydrochlorothiazide", "E": "Furosemide"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 13-year-old girl is brought to the physician because of worsening fever, headache, photophobia, and nausea for 2 days. One week ago, she returned from summer camp. She has received all age-appropriate immunizations. Her temperature is 39.1°C (102.3°F). She is oriented to person, place, and time. Physical examination shows a maculopapular rash. There is rigidity of the neck; forced flexion of the neck results in involuntary flexion of the knees and hips. Cerebrospinal fluid studies show:\nOpening pressure 120 mm H2O\nAppearance Clear\nProtein 47 mg/dL\nGlucose 68 mg/dL\nWhite cell count 280/mm3\nSegmented neutrophils 15%\nLymphocytes 85%\nWhich of the following is the most likely causal organism?\"", "answer": "Echovirus", "options": {"A": "Echovirus", "B": "Listeria monocytogenes", "C": "Herpes simplex virus", "D": "Streptococcus pneumoniae", "E": "Neisseria meningitidis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-year-old boy presents to his pediatrician for a well-child visit. His mother reports him to be doing well and has no concerns. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. On physical exam, he is noted to have a right upper extremity blood pressure of 150/80 mm Hg. 2+ radial pulses and trace femoral pulses are felt. Cardiac auscultation reveals a regular rate and rhythm with a normal S1 and S2. A 2/6 long systolic murmur with systolic ejection click is heard over left sternal border and back. The point of maximal impact is normal Which of the following is the most likely diagnosis?", "answer": "Coarctation of the aorta", "options": {"A": "Takayasu arteritis", "B": "Interrupted aortic arch", "C": "Pheochromocytoma", "D": "Coarctation of the aorta", "E": "Essential hypertension"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old woman comes to the physician for a follow-up examination. Two months ago, she underwent left renal transplantation for recurrent glomerulonephritis. At the time of discharge, her creatinine was 0.9 mg/dL. She feels well. Current medications include tacrolimus and azathioprine. Her pulse is 85/min and blood pressure is 135/75 mmHg. Physical examination shows a well-healed surgical scar on her left lower abdomen. The remainder of the examination shows no abnormalities. The patient should be monitored for which of the following adverse effects of her medications?", "answer": "Kidney injury", "options": {"A": "Teeth discoloration", "B": "Gingival hyperplasia", "C": "Hepatic necrosis", "D": "Kidney injury", "E": "Polycythemia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old woman comes to the physician because of a 12 month history of progressive fatigue and shortness of breath with exertion. Five years ago, she emigrated from Eastern Europe. She has smoked one pack of cigarettes daily for 20 years. She has a history of using methamphetamines and cocaine but quit 5 years ago. Vital signs are within normal limits. Physical examination shows jugular venous pulsations 9 cm above the sternal angle. The lungs are clear to auscultation. There is a normal S1 and a loud, split S2. An impulse can be felt with the fingers left of the sternum. The abdomen is soft and nontender. The fingertips are enlarged and the nails are curved. There is pitting edema around the ankles bilaterally. An x-ray of the chest shows pronounced central pulmonary arteries and a prominent right heart border. Which of the following is most likely to confirm the diagnosis?", "answer": "Right-heart catheterization", "options": {"A": "CT angiography", "B": "Doppler echocardiography", "C": "High-resolution CT of the lung", "D": "Right-heart catheterization", "E": "Serologic testing"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old man is admitted to the emergency department following a motorcycle accident. The patient is severely injured and requires life support after splenectomy and evacuation of a subdural hematoma. Past medical history is unremarkable. The patient’s family members, including wife, parents, siblings, and grandparents, are informed about the patient’s condition. The patient has no living will and there is no durable power of attorney. The patient must be put in an induced coma for an undetermined period of time. Which of the following is responsible for making medical decisions for the incapacitated patient?", "answer": "The spouse", "options": {"A": "An older sibling", "B": "The parents", "C": "Physician", "D": "Legal guardian", "E": "The spouse"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 11-year-old girl is brought to the physician by her parents because of a mildly pruritic rash on her trunk and extremities for 2 days. One week ago, she developed a low-grade fever, rhinorrhea, and headache, followed by a facial rash 4 days later. The facial rash did not involve the perioral skin. Her temperature is 37.4°C (99.3°F). A photograph of the rash on her lower arms is shown. Which of the following is the most likely diagnosis?", "answer": "Erythema infectiosum", "options": {"A": "Rubella", "B": "Erythema infectiosum", "C": "Hand, foot, and mouth disease", "D": "Exanthem subitum", "E": "Scarlet fever"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 11-year-old boy is brought to the emergency department by his parents with a 2-day history of fever, malaise, and productive cough. On presentation, he is found to be very weak and is having difficulty breathing. His past medical history is significant for multiple prior infections requiring hospitalization including otitis media, upper respiratory infections, pneumonia, and sinusitis. His family history is also significant for a maternal uncle who died of an infection as a child. Lab findings include decreased levels of IgG, IgM, IgA, and plasma cells with normal levels of CD4 positive cells. The protein that is most likely defective in this patient has which of the following functions?", "answer": "Protein phosphorylation", "options": {"A": "Actin polymerization", "B": "Autoimmune regulation", "C": "Lysosomal trafficking", "D": "Nucleotide salvage", "E": "Protein phosphorylation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A two-month-old female presents to the emergency department for difficulty feeding. The patient was born at 38 weeks gestation to a 29-year-old primigravid via vaginal delivery. The newborn period has thus far been uncomplicated. The patient has been exclusively breastfed since birth. Her parents report that feeding had previously seemed to be going well, and the patient has been gaining weight appropriately. Over the past several days, the patient’s mother has noticed that the patient seems to tire out before the end of the feeding. She has also noticed that the patient begins to appear short of breath and has a bluish discoloration of her lips. The patient’s height and weight were in the 20th and 10th percentile at birth, respectively. Her current height and weight are in the 20th and 15th percentiles, respectively. Her temperature is 98.0°F (36.7°C), blood pressure is 60/48 mmHg, pulse is 143/min, and respirations are 40/min. On physical exam, the patient is in no acute distress and appears well developed. A systolic crescendo-decrescendo murmur can be heard at the left upper sternal border. Her abdomen is soft, non-tender, and non-distended. During the abdominal exam, the patient begins crying and develops cyanosis of the perioral region.\n\nWhich of the following is the best initial test to diagnose this patient’s condition?", "answer": "Echocardiogram", "options": {"A": "Chest radiograph", "B": "CT angiography", "C": "Electrocardiogram", "D": "Echocardiogram", "E": "Genetic testing"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old male is evaluated for frequent epistaxis and mucous membrane bleeding. Physical examination shows diffuse petechiae on the patient’s distal extremities. Peripheral blood smear shows an absence of platelet clumping. An ELISA binding assay reveals that platelet surfaces are deficient in GIIb/IIIa receptors. Serum platelet count is normal. Which of the following is the most likely diagnosis?", "answer": "Glanzmann’s thrombasthenia", "options": {"A": "Hemophilia A", "B": "Thrombotic thrombocytopenic purpura", "C": "Bernard-Soulier disease", "D": "Idiopathic thrombocytopenic purpura", "E": "Glanzmann’s thrombasthenia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old man was a driver in a motor vehicle collsion. The patient is not able to offer a medical history during initial presentation. His temperature is 97.6°F (36.4°C), blood pressure is 104/74 mmHg, pulse is 150/min, respirations are 12/min, and oxygen saturation is 98% on room air. On exam, he does not open his eyes, he withdraws to pain, and he makes incomprehensible sounds. He has obvious signs of trauma to the chest and abdomen. His abdomen is distended and markedly tender to palpation. He also has an obvious open deformity of the left femur. What is the best initial step in management?", "answer": "Intubation", "options": {"A": "100% oxygen", "B": "Emergency open fracture repair", "C": "Exploratory laparoscopy", "D": "Intubation", "E": "Packed red blood cells"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 81-year-old woman comes to the emergency department due to a left-sided paralysis for the past 2 hours. Her husband says her symptoms began suddenly, and she is also unable to speak. Her pulse is 90/min, respirations are 18/min, temperature is 36.8°C (98.2°F), and blood pressure is 150/98 mm Hg. An ECG is obtained and is shown below. Which of the following is the most probable cause of the patient's paralysis?", "answer": "Cardioembolic stroke", "options": {"A": "Cardioembolic stroke", "B": "Cocaine toxicity", "C": "Conversion disorder", "D": "Hemorrhagic disorder", "E": "Rupture of berry aneurysm"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old female with a history of poorly-controlled diabetes presents to her primary care physician because of pain and tingling in her hands. These symptoms began several months ago and have been getting worse such that they interfere with her work as a secretary. She says that the pain is worse in the morning and she has been woken up at night by the pain. The tingling sensations have been located primarily in the thumb, index and middle fingers. On physical exam atrophy of the thenar eminence is observed and the pain is reproduced when the wrist is maximally flexed. The most likely cause of this patient's symptoms affects which of the nerves shown in the image provided?", "answer": "D", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old man is brought to the emergency department because of a 2-day history of fever and right upper quadrant abdominal pain. Examination shows jaundice. Ultrasonography of the abdomen shows cholelithiasis and marked dilation of the biliary duct. An ERCP is performed and reveals pus with multiple brown concrements draining from the common bile duct. Which of the following is the most likely underlying cause of the patient's findings?", "answer": "Increased β-glucuronidase activity", "options": {"A": "Increased alanine aminotransferase activity", "B": "Decreased heme oxygenase activity", "C": "Decreased HMG-coenzyme A reductase activity", "D": "Increased cholesterol 7-α hydroxylase activity", "E": "Increased β-glucuronidase activity"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 9-year-old boy presents for incision and drainage of a small abscess on his left thigh. No significant past medical history. No current medications. Before the procedure, the patient is allowed to inhale colorless, sweet-smelling gas. After the procedure, the patient receives 3–4 minutes of high flow oxygen through a nasal mask. The pulse oximetry shows an oxygen saturation of 94%. This patient was oxygenated at the end of the procedure to prevent which of the following complications?", "answer": "Diffusion hypoxia", "options": {"A": "Malignant hyperthermia", "B": "Cardiac arrhythmias", "C": "Raised intracranial pressure", "D": "Hepatotoxicity", "E": "Diffusion hypoxia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 50-year-old man presents to his primary care physician with a chief complaint of chest pain that is squeezing in nature. He used to have similar symptoms in the past while playing tennis with his friends. Yesterday, while moving furniture in his new home, he experienced this pain that lasted for 20 minutes and radiated towards his jaw and shoulder. He has been diagnosed with diabetes mellitus and hypertension for over 10 years and regularly takes his medications. The pain is not associated with nausea, vomiting, food intake, sweating, or cough. On physical examination, the patient is not in acute distress. His blood pressure is 135/85 mm Hg, heart rate is 80/min, respiratory rate is 16/min, temperature is 36.9°C (98.5°F), and BMI is 30 kg/m2. On physical examination, bilateral vesicular breath sounds are heard with absent chest tenderness. Cardiovascular examination reveals normal S1 and S2 without any abnormal sounds or murmur. Abdominal examination is within normal limit. What is the most likely cause of this patient’s condition?", "answer": "Myocardial ischemia", "options": {"A": "GERD", "B": "Musculoskeletal pain", "C": "Rib fracture", "D": "Anxiety", "E": "Myocardial ischemia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man presents to his physician with a complaint of recurrent episodes of palpitations over the past 2 weeks. He also mentions that he tends to tire easily. He denies chest pain, breathlessness, dizziness, or syncope, but has a history of ischemic heart disease. He smokes 1 pack of cigarettes every day and drinks alcohol occasionally. The physical examination revealed a temperature of 36.9°C (98.4°F), a pulse of 124/min (irregular), a blood pressure of 142/86 mm Hg, and a respiratory rate of 16/min. Auscultation of his chest is normal with an absence of rales overall lung fields. An ECG was significant for fibrillatory waves and an irregular RR interval. Thus, the physician concludes that the symptoms are due to atrial fibrillation. The patient is prescribed oral diltiazem. Which of the following side effects should the physician warn the patient about?", "answer": "Bilateral pedal edema", "options": {"A": "Hypoglycemia", "B": "Bilateral pedal edema", "C": "Bloody diarrhea", "D": "Stevens-Johnson syndrome", "E": "Multifocal atrial tachycardia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old female presents to her primary care physician complaining of body aches and constipation. She reports that her “bones hurt” and that she has experienced worsening constipation over the past few months. Her medical history is notable for three kidney stones within the past year that both passed spontaneously. Her vital signs are stable. Physical examination reveals a small nodule near the right inferior pole of the thyroid. Which of the following sets of serum findings is most likely in this patient?", "answer": "Increased calcium, decreased phosphate, increased parathyroid hormone", "options": {"A": "Increased calcium, decreased phosphate, increased parathyroid hormone", "B": "Decreased calcium, increased phosphate, increased parathyroid hormone", "C": "Increased calcium, decreased phosphate, decreased parathyroid hormone", "D": "Decreased calcium, increased phosphate, decreased parathyroid hormone", "E": "Normal calcium, normal phosphate, normal parathyroid hormone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 12-hour old male infant is seen in the newborn nursery. He was born full term by vaginal delivery to a 40-year-old G4P3-->4 mother. Her pregnancy and delivery were uncomplicated, notable only for declining genetic testing. On exam, her son has a flat face, a fold in the upper eyelid, palpebral fissures that appear to slant upwards, and small ears. The diagnostic test for her son’s most likely condition should be conducted during which of the following phases of the cell cycle?", "answer": "Metaphase", "options": {"A": "Prophase", "B": "Metaphase", "C": "Anaphase", "D": "Telophase", "E": "S-phase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old woman with a past medical history significant for pernicious anemia and vitiligo presents to the physician with the chief complaints of heat intolerance and frequent palpitations. The patient does not take birth control and her urine pregnancy test is negative today. Physical exam reveals a patient that is hyper-reflexive with a non-tender symmetrically enlarged thyroid gland. You order thyroid function tests for workup. What thyroid function values are most expected?", "answer": "T4 elevated, free T4 elevated, T3 elevated, TSH decreased", "options": {"A": "T4 elevated, free T4 normal, T3 elevated, thyroid stimulating hormone (TSH) normal", "B": "T4 elevated, free T4 elevated, T3 elevated, TSH elevated", "C": "T4 elevated, free T4 elevated, T3 elevated, TSH decreased", "D": "T4 decreased, free T4 decreased, T3 decreased, TSH decreased", "E": "T4 normal, free T4 normal, T3 normal, TSH elevated"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 75-year-old woman presents to her primary care physician with her son because she is convinced that people are stealing from her. Her son claims she has been misplacing her medications and money throughout the house. She recently lost her husband to old age and has become reclusive and no longer wants people to visit. Physical examination is unremarkable and the patient is oriented to person, time, and place. A mini-mental status examination (MMSE) is performed and she has difficulty recalling words after 5 minutes and also has problems with serial subtraction. Which of the following is the most likely diagnosis in this patient?", "answer": "Dementia", "options": {"A": "Delirium", "B": "Dementia", "C": "Histrionic personality disorder", "D": "Schizoid personality disorder", "E": "Schizophrenia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 67-year-old man comes to the office due to pain in the lower part of his calves on his afternoon walk to get the mail. The pain is relieved by rest. It started slowly about 6 months ago and has become more painful over time. He has a history of hypertension, hyperlipidemia, diabetes mellitus, and smoking. Medications include hydrochlorothiazide, atorvastatin, metformin, and a multivitamin that he takes daily. The patient does not smoke and only drinks socially. Today, his blood pressure is 145/90 mm Hg, pulse is 75/min, respiratory rate is 17/min, and temperature is 37.6°C (99.6°F). On physical exam, he appears mildly obese and healthy. His heart has a regular rate and rhythm, and his lungs are clear to auscultation bilaterally. Examination of the legs shows atrophic changes and diminished pedal pulses. A measure of his ankle brachial index (ABI) is 0.89. Which of the following is the most appropriate initial treatment?", "answer": "A referral to a supervised exercise program", "options": {"A": "Enoxaparin", "B": "Metoprolol", "C": "A recommendation to perform pedal pumping exercises", "D": "A recommendation to walk more", "E": "A referral to a supervised exercise program"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old man presents to his primary care physician with worsening cough and asthma. The patient reports that he was in his usual state of health until 1 month ago, when he developed a cold. Since then his cold has improved, but he continues to have a cough and worsening asthma symptoms. He says that he has been using his rescue inhaler 3 times a day with little improvement. He is studying for an accounting exam and states that his asthma is keeping him up at night and making it hard for him to focus during the day. The patient admits to smoking tobacco. His smoking has increased from a half pack per day since he was 17 years old to 1 pack per day during the past month to cope with the stress of his exam. The patient’s temperature is 99°F (37.2°C), blood pressure is 110/74 mmHg, pulse is 75/min, and respirations are 15/min with an oxygen saturation of 97% on room air. Physically examination is notable for mild expiratory wheezes bilaterally. Labs are obtained, as shown below:\n\nSerum:\nNa+: 144 mEq/L\nCl-: 95 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 23 mEq/L\nUrea nitrogen: 24 mg/dL\nGlucose: 100 mg/dL\nCreatinine: 1.6 mg/dL\n\nLeukocyte count and differential:\nLeukocyte count: 13,000/mm^3\nSegmented neutrophils: 63%\nEosinophils: 15%\nBasophils: < 1%\nLymphocytes: 20%\nMonocytes: 1.3%\nHemoglobin: 13.5 g/dL\nHematocrit: 50%\nPlatelets: 200,000/mm^3\n\nUrinalysis reveals proteinuria and microscopic hematuria. Which of the following is associated with the patient’s most likely diagnosis?", "answer": "p-ANCA levels", "options": {"A": "c-ANCA levels", "B": "Hepatitis B surface antigen", "C": "IgA deposits", "D": "p-ANCA levels", "E": "Smoking"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old man is brought to the physician because of fatigue, lethargy, and lower leg swelling for 2 weeks. He also noticed that his urine appeared darker than usual and for the last 2 days he has passed only small amounts of urine. His temperature is 37.5°C (98.6°F), pulse is 88/min, respirations are 15/min, and blood pressure is 154/98 mm Hg. Examination shows 2+ pretibial edema bilaterally. Laboratory studies show:\nHemoglobin 10.9 g/dL\nLeukocyte count 8200/mm3\nPlatelet count 220,000/mm3\nSerum\nNa+ 137 mEq/L\nCl- 102 mEq/L\nK+ 4.8 mEq/L\nHCO3- 22 mEq/L\nGlucose 85 mg/dL\nUrea nitrogen 34 mg/dL\nCreatinine 1.4 mg/dL\nUrine\nBlood 2+\nProtein 3+\nGlucose negative\nRBC 10–12/HPF with dysmorphic features\nRBC casts numerous\nRenal biopsy specimen shows a crescent formation in the glomeruli with extracapillary cell proliferation. Which of the following is the most appropriate next step in management?\"", "answer": "Administer methylprednisolone", "options": {"A": "Administer rituximab", "B": "Administer lisinopril", "C": "Perform hemodialysis", "D": "Administer methylprednisolone", "E": "Administer cyclosporine A"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 54-year-old man comes to the physician because of a painful mass in his left thigh for 3 days. He underwent a left lower limb angiography for femoral artery stenosis and had a stent placed 2 weeks ago. He has peripheral artery disease, coronary artery disease, hypercholesterolemia and type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for 34 years. Current medications include enalapril, aspirin, simvastatin, metformin, and sitagliptin. His temperature is 36.7°C (98°F), pulse is 88/min, and blood pressure is 116/72 mm Hg. Examination shows a 3-cm (1.2-in) tender, pulsatile mass in the left groin. The skin over the area of the mass shows no erythema and is cool to the touch. A loud bruit is heard on auscultation over this area. The remainder of the examination shows no abnormalities. Results of a complete blood count and serum electrolyte concentrations show no abnormalities. Duplex ultrasonography shows an echolucent sac connected to the common femoral artery, with pulsatile and turbulent blood flow between the artery and the sac. Which of the following is the most appropriate next best step in management?", "answer": "Ultrasound-guided thrombin injection", "options": {"A": "Ultrasound-guided thrombin injection", "B": "Coil embolization", "C": "Ultrasound-guided compression", "D": "Schedule surgical repair", "E": "Covered stent implantation\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old woman presents to the emergency department with acute onset vomiting, vertigo, throbbing headache, and weakness. She says that the symptoms started when she went to dinner with friends and had a drink of alcohol. Her past medical history is significant for type 2 diabetes, and she was recently started on a new medication for this disease. She says that she was warned that she might experiences these symptoms as a side effect of a new medication, but she did not realize how severe they would be. Which of the following describes the mechanism of action for the most likely diabetes drug that this patient started taking?", "answer": "Closing potassium channels", "options": {"A": "Binding to peroxisome proliferator-activating receptors", "B": "Closing potassium channels", "C": "Decreasing hepatic gluconeogenesis", "D": "Inhibiting alpha-glucosidase", "E": "Inhibiting dipeptidyl peptidase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old woman is brought to the emergency department for shortness of breath and chest pain. Pulmonary angiography shows a large saddle embolus in the pulmonary arteries. Emergency drug therapy is administered and she is admitted to the hospital for observation. A follow-up CT scan of the chest shortly after admission shows that the thrombus has disappeared. Five hours later, the patient is found to be lethargic with slurred speech. Physical examination shows decreased consciousness, dysarthria, and optic disc swelling bilaterally. Which of the following is the most likely cause of her neurological symptoms?", "answer": "Intracerebral hemorrhage\n\"", "options": {"A": "Acute metabolic encephalopathy", "B": "Idiopathic intracranial hypertension", "C": "Drug-induced hypotension", "D": "Embolic cerebrovascular accident", "E": "Intracerebral hemorrhage\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-day-old infant who was born via uncomplicated vaginal delivery at 39 weeks of gestation is brought to the family physician for poor feeding. The mother received adequate prenatal care throughout the pregnancy, and has no medical conditions. On physical exam, the infant's temperature is 36.5°C (97.7°F), blood pressure is 70/45 mmHg, pulse is 170/min, and respirations are 40/min. The infant has dry mucous membranes, capillary refill of 4 seconds, and a depressed anterior fontanelle. No abdominal masses are noted. Genital exam shows enlargement of the clitoris with fusion of the labioscrotal folds. Serum chemistry is remarkable for hyponatremia and hyperkalemia. The infant's karyotype is 46,XX. Which of the following findings are most likely to be discovered upon further workup?", "answer": "Increased sex hormones, increased 17-hydroxyprogesterone", "options": {"A": "Increased aldosterone, decreased cortisol", "B": "Decreased aldosterone, increased 11-deoxycorticosterone", "C": "Increased sex hormones, increased 17-hydroxyprogesterone", "D": "Increased sex hormones, decreased renin activity", "E": "Decreased cortisol, decreased sex hormones"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old man is brought to the physician because of increasing pain and swelling of the left knee for 2 months. The pain has awoken him from his sleep on multiple occasions. He tried ibuprofen but has had no relief of his symptoms. There is no family or personal history of serious illness. Vital signs are within normal limits. On examination, the left knee is mildly swollen and tender; range of motion is limited by pain. An x-ray of the left knee is shown. Which of the following is the most likely diagnosis?", "answer": "Osteoclastoma", "options": {"A": "Chondrosarcoma", "B": "Fibrous dysplasia", "C": "Aneurysmal bone cyst", "D": "Osteoclastoma", "E": "Ewing sarcoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 12-year-old boy is brought in by his parents as they are concerned about his behavior. He is constantly arguing with his parents and blatantly defying their every request. In school, he is known for being intentionally tardy and for defying his teachers. Upon further questioning of the patient you learn about some of his recent behaviors such as beginning smoking to bother his parents. You also notice that he is disrespectful towards you. You then learn that he has also gotten into weekly fights with his peers at school with no apparent cause. In addition, last week he was seen hitting one of the local neighborhood cats with a baseball bat trying to kill it. The patient lives at home with his two parents in a pre-World War II house that was recently renovated. Physical exam is unremarkable.\n\nLaboratory values are as follows:\n\nNa: 140 mmol/L\nK: 4.5 mmol/L\nCl: 100 mmol/L\nGlucose: 80 mg/dL\nCa: 10 mmol/L\nMg: 3 mEq/L\nCr: 0.8 mg/dL\nBUN: 10 mg/dL\nSerum lead: < .01 µg/dL\nHb: 15 g/dL\nHct: 45%\nMCV: 95\nUrine toxicology: negative\n\nAs the patient leaves the office you notice him stealing all of the candy from the office candy bowl. The patient seems unconcerned about his behavior overall. Which of the following statements is most likely to be true in this patient?", "answer": "The patient's symptoms could progress to antisocial personality disorder", "options": {"A": "This patient will likely function normally despite continuing to defy authority figures", "B": "This patient is suffering from antisocial personality disorder and will likely be incarcerated in adulthood", "C": "Environmental exposures are likely causing this patient's behavior", "D": "The patient's symptoms could progress to antisocial personality disorder", "E": "Strong D2 antagonists are first-line pharmacotherapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-hour-old girl is found to be cyanotic in the newborn nursery. She was born via spontaneous vaginal delivery at 38 weeks gestation to a gravida 1, para 0 healthy mother who received routine prenatal care. The patient is small for her gestational age. She manifests lower-extremity cyanosis along with a mesh-like mass on the back of her neck. Her vital signs are: pulse, 150/min; respirations, 48/min; and blood pressure, 120/80 mm Hg in the right arm, 124/82 mm Hg in the left arm, 80/40 mm Hg in the right leg, and 85/45 mm Hg in the left leg. Femoral pulses are 1+ and delayed. Cardiac examination shows a continuous murmur in the interscapular area. Auscultation of the lung reveals faint crackles at the base of the lung fields bilaterally. Which of the following is the most appropriate next step in management?", "answer": "Administration of alprostadil", "options": {"A": "Administration of alprostadil", "B": "Arteriogram", "C": "Echocardiography", "D": "Indomethacin", "E": "Lower extremity Doppler"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 5-year-old boy is brought to the emergency department for right elbow swelling and pain 45 minutes after he fell while playing on the monkey bars during recess. He has been unable to move his right elbow since the fall. Examination shows ecchymosis, swelling, and tenderness of the right elbow; range of motion is limited by pain. The remainder of the examination shows no abnormalities. An x-ray of the right arm is shown. Which of the following is the most likely complication of this patient's injury?", "answer": "Absent radial pulse", "options": {"A": "Polymicrobial infection", "B": "Absent radial pulse", "C": "Impaired extension of the wrist and hand", "D": "Avascular necrosis of the humeral head", "E": "Adhesive capsulitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3-month-old boy presents for routine health maintenance. The patient has coarse facial features and stiff joint movements with restricted passive and active range of motion. He also has problems following objects with his eyes and seems not to focus on anything. On physical examination, the corneas are clouded, and the patient fails to meet any 3-month developmental milestones. Genetic testing and histopathology are performed and reveal failure of a cellular structure to phosphorylate mannose residues on glycoproteins. An electron microscopy image of one of this patient’s cells is shown. Which of the following is the most likely diagnosis in this patient?", "answer": "Inclusion cell disease", "options": {"A": "Kartagener syndrome", "B": "Adrenoleukodystrophy", "C": "Inclusion cell disease", "D": "Diamond-Blackfan anemia", "E": "Tay-Sachs disease"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 36-year-old woman comes to the physician for a routine gynecological examination. She feels well. Menses occur with normal flow at regular 28-day intervals and last for 3 to 5 days. Her last menstrual period was 20 days ago. She is sexually active with one male partner and they use condoms inconsistently. Her sister was diagnosed with breast cancer at the age of 40 years. She drinks a glass of wine occasionally with dinner and has smoked 10 cigarettes daily for the past 15 years. The patient's vital signs are within normal limits. Physical examination including a complete pelvic exam shows no abnormalities. Urine pregnancy test is negative. A Pap smear shows atypical glandular cells. Which of the following is the most appropriate next step in management?", "answer": "Perform colposcopy with endocervical and endometrial sampling", "options": {"A": "Repeat cervical cytology at 12 months", "B": "Perform colposcopy with endocervical and endometrial sampling", "C": "Perform a diagnostic loop electrosurgical excision", "D": "Perform colposcopy and cytology every 6 months for 2 years", "E": "Perform colposcopy with endocervical sampling"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 59-year-old male presents to his primary care physician complaining of muscle weakness. Approximately 6 months ago, he started to develop gradually worsening right arm weakness that progressed to difficulty walking about three months ago. His past medical history is notable for a transient ischemic attack, hypertension, hyperlipidemia, and diabetes mellitus. He takes aspirin, lisinopril, atorvastatin, metformin, and glyburide. He does not smoke and he drinks alcohol occasionally. Physical examination reveals 4/5 strength in right shoulder abduction and right arm flexion. A tremor is noted in the right hand. Strength is 5/5 throughout the left upper extremity. Patellar reflexes are 3+ bilaterally. Sensation to touch and vibration is intact in the bilateral upper and lower extremities. Tongue fasciculations are noted. Which of the following is the most appropriate treatment in this patient?", "answer": "Riluzole", "options": {"A": "Natalizumab", "B": "Selegeline", "C": "Bromocriptine", "D": "Benztropine", "E": "Riluzole"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man presents to the emergency department for sudden weakness. The patient states that he was at home enjoying his morning coffee when his symptoms began. He says that his left arm suddenly felt very odd and weak thus prompting him to come to the ED. The patient has a past medical history of diabetes, COPD, hypertension, anxiety, alcohol abuse, and PTSD. He recently fell off a horse while horseback riding but claims to not have experienced any significant injuries. He typically drinks 5-7 drinks per day and his last drink was yesterday afternoon. His current medications include insulin, metformin, atorvastatin, lisinopril, albuterol, and fluoxetine. His temperature is 99.5°F (37.5°C), blood pressure is 177/118 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 93% on room air. On physical exam, you note an elderly man who is mildly confused. Cardiopulmonary exam demonstrates bilateral expiratory wheezes and a systolic murmur along the right upper sternal border that radiates to the carotids. Neurological exam reveals cranial nerves II-XII as grossly intact with finger-nose exam mildly abnormal on the left and heel-shin exam within normal limits. The patient has 5/5 strength in his right arm and 3/5 strength in his left arm. The patient struggles to manipulate objects such as a pen with his left hand. The patient is given a dose of diazepam and started on IV fluids. Which of the following is the most likely diagnosis in this patient?", "answer": "Lipohyalinosis", "options": {"A": "Berry aneurysm rupture", "B": "Bridging vein tear", "C": "Cerebellar bleeding", "D": "Hypertensive encephalopathy", "E": "Lipohyalinosis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 18-year-old male was brought to the emergency room after he caused an accident by driving at a slow speed as he was entering the freeway. He appears to have sustained no major injuries just minor scratches and lacerations, but appears to be paranoid, anxious, and is complaining of thirst. He has conjunctival injection and has slowed reflexes. A police officer explained that he had confiscated contraband from the vehicle of the male. Which of the following substances was most likely used by the male?", "answer": "Marijuana", "options": {"A": "Phencyclidine (PCP)", "B": "Cocaine", "C": "Heroin", "D": "Alprazolam", "E": "Marijuana"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old woman presents to the emergency department with right upper quadrant (RUQ) pain. She reports that the pain is not new and usually starts within half an hour of eating a meal. The pain has been previously diagnosed as biliary colic, and she underwent a cholecystectomy three months ago for symptomatic biliary colic. Her liver reportedly looked normal at that time. The patient dates the onset of these episodes to shortly after she underwent a sleeve gastrectomy several years ago, and the episodes were more severe immediately following that surgery. Her postsurgical course was otherwise uncomplicated, and she has lost fifty pounds since then. She has a past medical history of hypertension, hyperlipidemia, diabetes mellitus, osteoarthritis, and obesity. She denies alcohol or tobacco use. Her home medications are hydrochlorothiazide, enalapril, atorvastatin, and vitamin supplements. RUQ ultrasound reveals a surgically absent gallbladder and a dilated common bile duct without evidence of stones. Magnetic resonance cholangiopancreatography (MRCP) shows no evidence of biliary compression or obstruction, and endoscopic retrograde cholangiopancreatography (ERCP) shows no evidence of biliary stones or sludge. Laboratory tests are performed which reveal the following:\n\nALT: 47 U/L\nAST: 56 U/L\nAlkaline phosphatase: 165 U/L\nTotal bilirubin: 1.6 g/dL\nAmylase: 135 U/L\nLipase: 160 U/L\n\nWhich of the following is definitive treatment of this patient's condition?", "answer": "Sphincterotomy", "options": {"A": "Pancreaticoduodenectomy", "B": "Biliary stent", "C": "Pancreatic enzyme replacement", "D": "Sphincterotomy", "E": "Surgical revascularization"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 14-year-old male presents to the emergency department with altered mental status. His friends who accompanied him said that he complained of abdominal pain while camping. They denied his consumption of anything unusual from the wilderness, or any vomiting or diarrhea. His temperature is 100.5°F (38.1°C), blood pressure is 95/55 mmHg, pulse is 130/min, and respirations are 30/min. His pupils are equal and reactive to light bilaterally. The remainder of the physical exam is unremarkable. His basic metabolic panel is displayed below:\n\nSerum:\nNa+: 116 mEq/L\nCl-: 70 mEq/L\nK+: 4.0 mEq/L\nHCO3-: 2 mEq/L\nBUN: 50 mg/dL\nGlucose: 1010 mg/dL\nCreatinine: 1.2 mg/dL\n\nWhile the remainder of his labs are pending, the patient becomes bradypneic and is intubated. His ventilator is adjusted to volume control assist-control with a respiratory rate (RR) of 14/min, tidal volume (Vt) of 350 mL, positive end-expiratory pressure (PEEP) of 5 cm H2O, and fractional inspired oxygen (FiO2) of 40%. His height is 5 feet 5 inches. Intravenous fluids and additional medical therapy are administered. An arterial blood gas obtained after 30 minutes on these settings shows the following:\n\npH: 7.05\npCO2 :40 mmHg\npO2: 150 mmHg\nSaO2: 98%\n\nWhat is the best next step in management?", "answer": "Increase respiratory rate and tidal volume", "options": {"A": "Increase respiratory rate", "B": "Increase respiratory rate and tidal volume", "C": "Increase tidal volume", "D": "Increase tidal volume and positive end-expiratory pressure", "E": "Increase positive end-expiratory pressure"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 50-year-old woman comes to the physician because of multiple, ulcerative skin lesions that occur over various parts of her body. She reports that these rashes first appeared 6 months ago. They occur episodically and usually start as reddish spots, which then expand in size and ulcerate over the next ten days. They resolve spontaneously and reappear at another location a few days later. Over the past 6 months, has had multiple episodes of diarrhea. She has lost 8 kg weight over this period and feels tired constantly. She has not had fever. She was treated for deep venous thrombosis 3 years ago, and took medication for it for 6 months after the episode. Her vital signs are within normal limits. She appears pale and has multiple, tender, ulcerative skin lesions on her legs and buttocks. Her hemoglobin is 9.6 mg/dL, mean corpuscular volume is 82 μm3, and fingerstick blood glucose concentration is 154 mg/dL. Her serum glucagon is elevated. Abdominal ultrasonography reveals a 5.6 cm, well-demarcated, hypoechoic mass in the pancreatic body and multiple, small masses in the liver of variable echogenicity. Which of the following is the most appropriate next step in management of this patient?", "answer": "Administration of octreotide", "options": {"A": "Measurement of serum zinc levels", "B": "Endoscopic ultrasonongraphy", "C": "Obtaining cancer antigen 19-9 levels", "D": "Administration of octreotide", "E": "Measurement of glycated hemoglobin\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old female presents to her primary care physician for medical evaluation prior to an elective hip replacement surgery. She has hypertension and diabetes, both of which are well controlled on oral medications. She also admits to occasional use of recreational injection drugs so a panel of serologies are obtained. Based on the results, the patient is found to have had a previous infection with hepatitis B from which she has fully recovered. Which of the following is a characteristic of the immunoglobulin subtype that most likely binds to hepatitis B core antigen in this patient?", "answer": "It exists as a monomer", "options": {"A": "It exists as a monomer", "B": "It exists as a dimer", "C": "It exists as a pentamer", "D": "It activates mast cells", "E": "It is only activated by multivalent immunogens"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 40-year-old woman, gravida 2, para 2, comes to the physician because of fatigue, nausea, joint pain, and mild flank pain for 2 months. She has refractory acid reflux and antral and duodenal peptic ulcers for which she takes omeprazole. She also has chronic, foul-smelling, light-colored diarrhea. Five years ago she was successfully treated for infertility with bromocriptine. She reports recently feeling sad and unmotivated at work. She does not smoke or drink alcohol. She is 175 cm (5 ft 9 in) tall and weighs 100 kg (220 lb); BMI is 32.7 kg/m2. Her temperature is 37°C (98.8°F), pulse is 78/min, and blood pressure is 150/90 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is moderately distended and diffusely tender to palpation. There is mild costovertebral angle tenderness. Her serum calcium concentration is 12 mg/dL, phosphorus concentration is 2 mg/dL, and parathyroid hormone level is 900 pg/mL. Abdominal ultrasound shows mobile echogenic foci with acoustic shadowing in her ureteropelvic junctions bilaterally. A mutation in which of the following genes is most likely present in this patient?", "answer": "MEN1", "options": {"A": "NF2", "B": "VHL", "C": "C-Kit", "D": "RET", "E": "MEN1"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old woman comes to the physician because of multiple episodes of dizziness over the past 3 months. Episodes last between 20 minutes and 1 hour. During the episodes she experiences the sudden onset of spinning sensations and imbalance, associated with a ringing in her left ear. She also reports progressive left-sided hearing loss and is unable to follow conversations in noisy surroundings. She has had an upper respiratory infection for the past 5 days, which is being treated with erythromycin. She has been otherwise healthy. Her vital signs are within normal limits. Examination shows no abnormalities. Pure tone audiometry shows a combined low- and high-frequency sensory loss of the left ear with normal hearing in the mid frequencies. Which of the following is the most appropriate initial step in management?", "answer": "Reduce caffeine intake", "options": {"A": "Reduce caffeine intake", "B": "Begin topiramate therapy", "C": "Perform Epley maneuver", "D": "Discontinue erythromycin", "E": "Begin fluoxetine therapy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old woman comes to the emergency department for increasing abdominal pain and confusion for 3 days. The pain is constant and she describes it as 8 out of 10 in intensity. She has the strong feeling that she is being watched. She has not had a bowel movement for 2 days. She began experiencing tingling in parts of her lower extremities 4 hours ago. She consumed a large number of alcoholic beverages prior to the onset of the abdominal pain. Her temperature is 38°C (100.8°F), pulse is 113/min, and blood pressure is 148/88 mm Hg. She appears distracted and admits to hearing whispering intermittently during the examination, which shows a distended abdomen and mild tenderness to palpation diffusely. There is no guarding or rebound tenderness present. Bowel sounds are decreased. There is weakness of the iliopsoas and hamstring muscles. Sensation is decreased over the lower extremities. Deep tendon reflexes are 2+ in the lower extremities. Mental status examination shows she is oriented only to person and place. A complete blood count and serum concentrations of electrolytes, glucose, creatinine are within the reference range. Which of the following is the most appropriate next step in management?", "answer": "Hemin therapy", "options": {"A": "Chlordiazepoxide", "B": "Hemin therapy", "C": "Haloperidol therapy", "D": "Chloroquine", "E": "Glucose"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old boy is brought to his pediatrician by his mother for a physical exam before summer camp. They have no complaints or concerns at this time. He was born at 37 weeks gestation by cesarean delivery. The delivery was complicated by an omphalocele and macrosomia. During infancy and into early childhood, he struggled to breathe and eat due to an enlarged tongue. Growth and development were mostly normal with mild uneven growth of his body. He has one uncle that had similar symptoms and is alive and well. The child is up to date on all vaccines and is meeting developmental goals. He enjoys school and playing with his friends. His heart rate of 90/min, respiratory rate of 22/min, blood pressure of 110/65 mm Hg, and temperature of 36.9°C (98.4°F). Overall the child appears healthy. Physical exam findings include known hemihypertrophy of the right side along with a mildly enlarged tongue. This patient is at increased risk of developing which of the following?", "answer": "Wilms tumor", "options": {"A": "Scoliosis", "B": "Alzheimer's disease", "C": "Diabetes mellitus", "D": "Wilms tumor", "E": "Sudden infant death syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old man is brought to your office by his daughter due to concern over recent behavioral changes. Over the last several months he has had increasing difficulty with remembering recent events. She mentions that he is embarrassed due to a new inability to control urination. His medical history is significant for hypertension and insomnia. His medications include alprazolam and hydrochlorothiazide. On physical exam, he is oriented to time and place and thinks his daughter is exaggerating; however, when asked to recall 3 items, the patient refuses to continue the mental status exam. He has 5/5 strength bilaterally. He walks in short strides by sliding his feet across the floor. Which of the following would you expect to see in his patient?", "answer": "Distortion of corona radiata fibers", "options": {"A": "Distortion of corona radiata fibers", "B": "Atrophy of the caudate and putamen", "C": "Atrophy of the subthalamic nucleus", "D": "Depigmentation of the substantia nigra pars compacta", "E": "Convex hemorrhage that does not cross suture lines"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 11-year-old boy is brought to the pediatrician by his mother for vomiting. The patient has been vomiting for the past week, and his symptoms have not been improving. His symptoms are worse in the morning and tend to improve throughout the day. The patient also complains of occasional headaches and had diarrhea several days ago. The patient eats a balanced diet and does not drink soda or juice. The patient's brothers both had diarrhea recently that resolved spontaneously. His temperature is 99.5°F (37.5°C), blood pressure is 80/45 mmHg, pulse is 90/min, respirations are 16/min, and oxygen saturation is 98% on room air. On physical exam, the patient appears to be in no acute distress. Cardiopulmonary exam reveals a minor flow murmur. Neurological exam reveals cranial nerves II-XII as grossly intact with mild narrowing of the patient's visual fields. The patient's gait is stable, and he is able to jump up and down. Which of the following is the most likely direct cause of this patient's presentation?", "answer": "Remnant of Rathke's pouch", "options": {"A": "Non-enveloped, (+) ssRNA virus", "B": "Gram-negative microaerophilic bacteria", "C": "Gram-positive enterotoxin", "D": "Intracerebellar mass", "E": "Remnant of Rathke's pouch"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 35-year-old man is brought to the emergency department by his wife because of a 1-week history of progressive confusion, myalgia, and nausea. His wife says that he first reported headaches and fatigue 10 days ago, and since then “he has not been himself”. He has refused to drink any liquids for the last day. Two months ago, he helped his neighbor remove a raccoon's den from her backyard. He appears agitated. His temperature is 100.8°F (38.2°C). Examination shows excessive drooling. Muscle tone and deep tendon reflexes are increased bilaterally. Administration of which of the following is most likely to have prevented this patient's condition?", "answer": "Chemically-inactivated virus", "options": {"A": "RNA-dependent DNA polymerase inhibitor", "B": "Chemically-inactivated virus", "C": "Live attenuated vaccine", "D": "Immunoglobulin against a bacterial protein", "E": "Inosine monophosphate dehydrogenase inhibitor"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 29-year-old patient presents to her primary care physician with persistent amenorrhea and inability to breastfeed over the last 5 months. She says that she has also been very tired since her baby was born and this fatigue was accompanied by an inability to deal with cold weather despite having no problem with cold prior to becoming pregnant. She has gained an additional 5 pounds since delivery. Review of her hospital records reveals that she had a vaginal delivery that was complicated by severe hemorrhage and episodes of hypotension. Which of the following hormone levels is most likely to be normal in this patient?", "answer": "Aldosterone", "options": {"A": "Follicle-stimulating hormone (FSH)", "B": "Prolactin", "C": "Thyroid hormone", "D": "Cortisol", "E": "Aldosterone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old G2P1 delivers a boy in the 40th week of gestation. The pregnancy was uncomplicated. The newborn had Apgar scores of 7 and 9 at the 1st and 5th minutes, respectively. On physical examination, the newborn is noted to have a left-sided cleft lip. The hard palate and nose are normal. Which of the following statements describes the cause of the abnormality?", "answer": "Failure of fusion of the left maxillary prominence and the medial nasal process of the frontonasal prominence", "options": {"A": "Failure of development of the first pharyngeal arch", "B": "Failure of fusion of the left maxillary prominence and the medial nasal process of the frontonasal prominence", "C": "Partial resorption of the first pharyngeal arch", "D": "Failure of fusion of the left maxillary prominence and the lateral nasal process of the frontonasal prominence", "E": "Failure of development of the left maxillary prominence"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 17-year-old male is diagnosed with acne vulgaris during a visit to a dermatologist. He is prescribed a therapy that is a derivative of vitamin A. He has no other significant past medical history. Which of the following is the major side-effect of this therapy?", "answer": "Hyperlipidemia", "options": {"A": "Hyperglycemia", "B": "Hyperlipidemia", "C": "Fatigue", "D": "Xerophthalmia", "E": "Alopecia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man presented to a medical clinic for a routine follow-up. He has had hypertension for 20 years and is currently on multiple anti-hypertensive medications. The blood pressure is 150/100 mm Hg. The remainder of the examinations were within normal limits. Echocardiography showed some changes in the left ventricle. What is the most likely reason for the change?", "answer": "Increase in cardiac cell size", "options": {"A": "Disordered growth of the cardiac cells", "B": "Replacement of cardiac cells into stronger red fiber skeletal cells", "C": "Decrease in cardiac cell size", "D": "Increase in cardiac cell size", "E": "Increase in number of normal cardiac cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old female presents to her primary care physician complaining of heat intolerance and difficulty sleeping over a one month period. She also reports that she has lost 10 pounds despite no changes in her diet or exercise pattern. More recently, she has developed occasional unprovoked chest pain and palpitations. Physical examination reveals a nontender, mildly enlarged thyroid gland. Her patellar reflexes are 3+ bilaterally. Her temperature is 99°F (37.2°C), blood pressure is 135/85 mmHg, pulse is 105/min, and respirations are 18/min. Laboratory analysis is notable for decreased TSH. Which of the following pathophysiologic mechanisms contributed to the cardiovascular symptoms seen in this patient?", "answer": "Increased sensitivity of ß1-adrenergic receptors", "options": {"A": "Increased numbers of a1-adrenergic receptors", "B": "Decreased numbers of a1-adrenergic receptors", "C": "Decreased numbers of a2-adrenergic receptors", "D": "Decreased sensitivity of ß2-adrenergic receptors", "E": "Increased sensitivity of ß1-adrenergic receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A neonate suffering from neonatal respiratory distress syndrome is given supplemental oxygen. Which of the following is a possible consequence of oxygen therapy in this patient?", "answer": "Blindness", "options": {"A": "Atelectasis", "B": "Anosmia", "C": "Atopy", "D": "Blindness", "E": "Cardiac anomalies"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old woman comes to the physician because of a 2-month history of fatigue and abdominal discomfort. Over the past 6 months, she has had a 5.4-kg (12-lb) weight loss. She takes no medications. Her temperature is 37.8°C (100°F), pulse is 70/min, respirations are 13/min, and blood pressure is 125/80 mm Hg. Cardiopulmonary examination shows no abnormalities. The spleen is palpated 3 cm below the left costal margin. Laboratory studies show:\nHemoglobin 9.4 g/dL\nMean corpuscular volume 86 μm3\nLeukocyte count 58,000/mm3\nSegmented neutrophils 54%\nBands 8%\nLymphocytes 7%\nMyelocytes 5%\nMetamyelocytes 10%\nPromyelocytes 4%\nBlasts 5%\nMonocytes 1%\nEosinophils 4%\nBasophils 2%\nPlatelet count 850,000/mm3\nSerum\nCreatinine\n0.9 mg/dL\nLDH 501 U/L\nBone marrow biopsy shows hyperplastic myelopoiesis with granulocytosis. Which of the following is the most appropriate next step in management?\"", "answer": "Cytogenetic studies", "options": {"A": "Cytarabine and daunorubicin", "B": "Serum protein electrophoresis", "C": "Cytogenetic studies", "D": "All-trans retinoic acid", "E": "Observation and follow-up"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70-year-old man presents to his physician for evaluation of fullness and swelling of the left side of the abdomen over the last month. During this time, he has had night sweats and lost 2 kg (4.4 lb) unintentionally. He has no history of severe illness and takes no medications. The vital signs include: blood pressure 115/75 mm Hg, pulse 75/min, and temperature 36.8℃ (98.2℉). The abdomen has asymmetric distention. Percussion and palpation of the left upper quadrant reveal splenomegaly. No lymphadenopathy is detected. Heart and lung examination shows no abnormalities. The laboratory studies show the following:\nHemoglobin 9.5 g/dL\nMean corpuscular volume 95 μm3\nLeukocyte count 8,000/mm3\nPlatelet count 240,000/mm3\nUltrasound shows a spleen size of 15 cm, mild hepatomegaly, and mild ascites. The peripheral blood smear shows teardrop-shaped and nucleated red blood cells (RBCs) and immature myeloid cells. Marrow is very difficult to aspirate but reveals hyperplasia of all 3 lineages. The tartrate-resistant acid phosphatase (TRAP) test is negative. The cytogenetic analysis is negative for translocation between chromosomes 9 and 22. Which of the following laboratory findings is most likely to be present in this patient?", "answer": "JAK-2 mutation", "options": {"A": "Monoclonal elevation of IgG", "B": "Hair-like cell-membrane projections", "C": "JAK-2 mutation", "D": "Philadelphia chromosome", "E": "Reed-Sternburg cells"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A physician is choosing whether to prescribe losartan or lisinopril to treat hypertension in a 56-year-old male. Relative to losartan, one would expect treatment with lisinopril to produce which of the following changes in the circulating levels of these peptides?", "answer": "Bradykinin increase; angiotensin II decrease", "options": {"A": "Bradykinin increase; angiotensin II decrease", "B": "Renin decrease; angiotensin 1 increase", "C": "Aldosterone increase; bradykinin decrease", "D": "Renin decrease; angiotensin II increase", "E": "Angiotensin II increase; bradykinin decrease"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old man presents to the urgent care clinic complaining of nausea and vomiting for the past 2 hours. He just returned from a boating trip with his father, and while aboard they shared some packed potato salad and ham sandwiches. His dad denies any nausea or vomiting but does report minor dizziness. On examination he appears pale. The patient reports similar symptoms in the past when he was on a cruise trip to the Bahamas. What is the best medication for this patient at this time?", "answer": "Diphenhydramine", "options": {"A": "Diphenhydramine", "B": "Guaifenesin", "C": "Loperamide", "D": "Loratadine", "E": "Ondansetron"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old man comes to the physician because of a 4-day history of fever and cough productive of foul-smelling, dark red, gelatinous sputum. He has smoked 1 pack of cigarettes daily for 30 years and drinks two 12-oz bottles of beer daily. An x-ray of the chest shows a cavity with air-fluid levels in the right lower lobe. Sputum culture grows gram-negative rods. Which of the following virulence factors is most likely involved in the pathogenesis of this patient's condition?", "answer": "Capsular polysaccharide", "options": {"A": "Exotoxin A", "B": "IgA protease", "C": "Heat-stable toxin", "D": "P-fimbriae", "E": "Capsular polysaccharide"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old girl is brought to the physician for evaluation of severe acne on her face, chest, and back for the past 2 years. She has no itching or scaling. She has been treated in the past with a combination of oral cephalexin and topical benzoyl peroxide without clinical improvement. She is sexually active with one male partner, and they use condoms inconsistently. She does not smoke, drink alcohol, or use illicit drugs. There is no personal or family history of serious illness. Her vital signs are within normal limits. Examination shows mild facial scarring and numerous open comedones and sebaceous skin lesions on her face, chest, and back. Before initiating treatment, which of the following is the most appropriate next step?", "answer": "Measure serum beta-hCG levels", "options": {"A": "Administer oral contraceptives", "B": "Screen for depression with a questionnaire", "C": "Switch cephalexin to doxycycline", "D": "Measure serum beta-hCG levels", "E": "Measure creatinine kinase levels"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 75-year-old woman is brought to the physician by her daughter for a 4-month history of increasing difficulty recognizing her friends and family. She has had to rely on recognizing haircuts, gait, and voices because she cannot remember their faces. Neurologic examination shows that she is able to recognize objects and name facial features such as the eyes and nose. On mental status examination, she is alert and has no deficits in cognition or short-term memory. An MRI of her head shows an inhomogenous 2-cm mass with perifocal edema in her brain. Which of the following brain regions is most likely affected?", "answer": "Right ventral occipitotemporal cortex", "options": {"A": "Left posterior parietal cortex", "B": "Right posterior superior temporal cortex", "C": "Left hippocampus", "D": "Right superior parietal cortex", "E": "Right ventral occipitotemporal cortex"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 25-year-old male patient presents to your clinic in significant distress. He states he has excruciating, stabbing pain around the left side of his head, and his left eye will not stop tearing. These types of headaches have been occurring for the past week every morning when he awakens and last around 60 minutes. He denies any aura, nausea, or vomiting. He denies any other past medical history. What is this patient's diagnosis?", "answer": "Cluster headache", "options": {"A": "Migraine headache", "B": "Cluster headache", "C": "Chronic paroxysmal hemicrania (CPH)", "D": "Short-lasting unilateral neuralgiform headaches with conjunctival injection and tearing (SUNCT) syndrome", "E": "Trigeminal neuralgia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old woman presents to the physician because of an abnormal breast biopsy report following suspicious findings on breast imaging. Other than being concerned about her report, she feels well. She has no history of any serious illnesses and takes no medications. She does not smoke. She consumes wine 1–2 times per week with dinner. There is no significant family history of breast or ovarian cancer. Vital signs are within normal limits. Physical examination shows no abnormal findings. The biopsy shows lobular carcinoma in situ (LCIS) in the left breast. Which of the following is the most appropriate next step in management?", "answer": "Careful observation + routine mammography", "options": {"A": "Breast irradiation + tamoxifen", "B": "Careful observation + routine mammography", "C": "Left mastectomy + axillary dissection + local irradiation", "D": "Lumpectomy + breast irradiation", "E": "Lumpectomy + routine screening"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 33-year-old woman comes to the emergency department because of a 3-day history of lower abdominal pain and severe burning with urination. Two years ago, she was diagnosed with cervical cancer and was successfully treated with a combination of radiation and chemotherapy. She has systemic lupus erythematosus and finished a course of cyclophosphamide 3 weeks ago. She is sexually active with multiple male and female partners and uses a diaphragm for contraception. She has smoked two packs of cigarettes daily for 12 years. Current medication includes hydroxychloroquine. Her temperature is 36.6°C (97.9°F), pulse is 84/min, and blood pressure is 136/84 mm Hg. The abdomen is soft and there is tenderness to palpation over the pelvic region. Laboratory studies show:\nHemoglobin 13.1 g/dL\nLeukocyte count 7,400/mm3\nPlatelet count 210,000/mm3\nUrine\npH 7\nWBC 62/hpf\nRBC 12/hpf\nProtein negative\nNitrites positive\nWhich of the following is the most likely underlying mechanism of this patient's condition?\"", "answer": "Ascending infection", "options": {"A": "Radiation-induced inflammation", "B": "Ascending infection", "C": "Sexually transmitted infection", "D": "Hematogenous spread of infection", "E": "Neural hypersensitivity"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 81-year-old man comes to the emergency department with severe left ear pain and drainage for 3 days. He has a history of poorly-controlled type 2 diabetes mellitus. He appears uncomfortable. Physical examination of the ear shows marked periauricular erythema, exquisite tenderness on palpation, and granulation tissue in the external auditory canal. The most likely causal pathogen produces an exotoxin that acts by a mechanism most similar to a toxin produced by which of the following organisms?", "answer": "Corynebacterium diphtheriae", "options": {"A": "Corynebacterium diphtheriae", "B": "Bordetella pertussis", "C": "Shigella dysenteriae", "D": "Staphylococcus aureus", "E": "Bacillus anthracis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman of Ashkenazi Jewish descent presents with recurrent bloody diarrhea and abdominal pain. She says she feels well otherwise. Review of systems is significant for a 4 kg weight loss over the past month. Physical examination is significant for multiple aphthous oral ulcers. Colonoscopy reveals a cobblestone pattern of lesions of the mucosa of the intestinal wall involving the sigmoid colon. The patient is informed of the diagnosis and medication to treat her condition is prescribed. On a follow-up visit 6 weeks later, the patient presents with non-productive cough, chest pain, dyspnea on exertion, and worsening oral lesions. A chest radiograph reveals a diffuse interstitial pattern. Which of the following enzymes is inhibited by the medication most likely prescribed for her initial diagnosis?", "answer": "Dihydrofolate reductase", "options": {"A": "Thymidylate synthase", "B": "Dihydrofolate reductase", "C": "Hypoxanthine guanine-phosphoribosyltransferase (HGPRT)", "D": "DNA polymerase", "E": "Thymidine kinase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old girl swallows a marble while playing and is rushed to the hospital by her mother. The patient’s mother says she suddenly started to cough violently and made \"funny breathing\" sounds for a few minutes which then resolved. Her pulse is 100/min and respirations are 28/min. Physical examination reveals a girl in no obvious distress and breathing comfortably. There are diminished breath sounds and mild expiratory wheezing over the lower right lung field. A chest X-ray is performed which shows a round foreign body about 1 cm ×1 cm in the lower portion of the right inferior lobe. Which of the following changes in blood flow through the affected part of the lung would most likely be present in this patient?", "answer": "Blood flow would be decreased due to arterial vasoconstriction.", "options": {"A": "Blood flow would be increased due to arterial vasodilation.", "B": "Blood flow would be increased due to active hyperemia.", "C": "Blood flow would be unchanged due to autoregulation.", "D": "Blood flow would be unchanged due to decreased surfactant.", "E": "Blood flow would be decreased due to arterial vasoconstriction."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A patient presents with periods of severe headaches and flushing however every time they have come to the physician they have not experienced any symptoms. The only abnormal finding is a blood pressure of 175 mmHg/100 mmHg. It is determined that the optimal treatment for this patient is surgical. Prior to surgery which of the following noncompetitive inhibitors should be administered?", "answer": "Phenoxybenzamine", "options": {"A": "Atropine", "B": "Isoproterenol", "C": "Propranolol", "D": "Phentolamine", "E": "Phenoxybenzamine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man with no significant medical history returns for follow-up of a fasting blood glucose (FBG) of 110 mg/dL. His mother had a myocardial infarction at age 52. He weighs 90 kg and his body mass index is 35 kg/m2. His repeat FBG is 160 mg/dL and hemoglobin A1c (HbA1c) is 7.0%. He is started on metformin but is lost to follow-up. Two years later, his HbA1c is 7.6% despite maximal metformin usage, so the patient is started on glyburide. Three months later, his HbA1c is 7.3% while on both medications, and subsequently prescribed glargine and aspart. Three months later, he is brought by his wife to the emergency department for evaluation of altered mental status. His electronic medical record notes that he was started on nitrofurantoin recently for an urinary tract infection. He is disoriented to place and time. His temperature is 99°F (37.2°C), blood pressure is 90/60 mmHg, pulse is 130/min, respirations are 26/min. His basic metabolic panel is shown below:\n\nSerum:\nNa+: 119 mEq/L\nCl-: 90 mEq/L\nK+: 4.2 mEq/L\nHCO3-: 24 mEq/L\nBUN: 25 mg/dL\nGlucose: 1,400 mg/dL\nCreatinine: 1.9 mg/dL\n\nHis urine dipstick is negative for ketones. A peripheral intravenous line is established. What is the best initial step in management?", "answer": "Lactated ringer's solution", "options": {"A": "3% hypertonic saline", "B": "Regular insulin", "C": "Lactated ringer's solution", "D": "Glargine insulin", "E": "Regular insulin and potassium"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 33-year-old woman comes to the emergency department for the evaluation of a headache and increased sweating for the last two hours. The patient also reports palpitations and nausea. Yesterday, she was started on venlafaxine for treatment-resistant depression. She took citalopram for four weeks, but stopped three days ago because her symptoms of depression did not improve. She does not smoke or drink alcohol. Her temperature is 39°C (102.2°F), pulse is 120/min, and blood pressure is 150/90 mm Hg. On mental status examination, the patient is only oriented to person, but not to place or time. Examination shows tremors in all extremities. She has impaired gait. Deep tendon reflexes are 3+ bilaterally. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Increased CNS serotonergic activity", "options": {"A": "Abnormal ryanodine receptor", "B": "Increased CNS serotonergic activity", "C": "Dopamine receptor blockade", "D": "Anticholinergic toxicity", "E": "Suspected amphetamine intake"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 67-year-old man with stable coronary artery disease comes to the physician for a follow-up examination. Aside from occasional exertional chest pain on mowing the lawn or prolonged jogging, he feels well. He goes jogging for 20 minutes once a week and takes a tablet of sublingual nitroglycerine prior to his run to prevent anginal chest pain. The patient would like to run longer distances and asks the physician whether he could increase the dose of the drug prior to running. Administration of higher dosages of this drug is most likely to result in which of the following?", "answer": "Reflex sympathetic activity", "options": {"A": "Rebound angina", "B": "Development of tolerance", "C": "Reflex sympathetic activity", "D": "Anaphylactic reaction", "E": "Coronary artery vasospasm"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old man presents with a 1-day-history of pain and difficulty moving his right shoulder. He was cleaning his attic when he fell through onto the floor below and landed on his outstretched right hand. He tried over-the-counter analgesics which did not help. Past medical history is unremarkable. The patient is afebrile and vital signs are within normal limits. On physical examination, there are no visible deformities in the shoulder or upper extremities bilaterally. When he is asked to abduct his right shoulder above his head, he could not move his right shoulder initially. He is able to do so only when he is assisted to complete a full abduction. There is no sensory loss in any part of the upper limbs. Peripheral pulses are 2+ bilaterally. A MRI of the right shoulder is performed (shown in the image). Which of the following structures is most likely injured?", "answer": "Supraspinatus tendon", "options": {"A": "Infraspinatus tendon", "B": "Supraspinatus tendon", "C": "Deltoid muscle", "D": "Subscapularis tendon", "E": "Teres minor tendon"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old woman is brought to the emergency department because of intermittent sharp right upper quadrant abdominal pain and nausea for the past 10 hours. She has vomited 3 times. There is no associated fever, chills, diarrhea, or urinary symptoms. She has 2 children who both attend high school. She appears uncomfortable. She is 165 cm (5 ft 5 in) tall and weighs 86 kg (190 lb). Her BMI is 32 kg/m2. Her temperature is 37.0°C (98.6°F), pulse is 100/min, and blood pressure is 140/90 mm Hg. She has mild scleral icterus. On physical examination, her abdomen is soft and nondistended, with tenderness to palpation of the right upper quadrant without guarding or rebound. Bowel sounds are normal. Laboratory studies show the following:\nBlood\nHemoglobin count 14 g/dL\nLeukocyte count 9,000 mm3\nPlatelet count 160,000 mm3\nSerum\nAlkaline phosphatase 238 U/L\nAspartate aminotransferase 60 U/L\nBilirubin  \nTotal 2.8 mg/dL\nDirect 2.1 mg/dL\nWhich of the following is the most appropriate next step in diagnosis?", "answer": "Transabdominal ultrasonography", "options": {"A": "Computed tomography (CT) scan of the abdomen", "B": "Endoscopic retrograde cholangiopancreatography (ERCP)", "C": "Hepatobiliary iminodiacetic acid (HIDA) scan of the biliary tract", "D": "Supine and erect X-rays of the abdomen", "E": "Transabdominal ultrasonography"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-year-old boy is brought to the physician by his parents because of difficulty walking and cold feet for the past 2 months. His parents report that he tires quickly from walking. The patient was born at 37 weeks' gestation and has met all developmental milestones. There is no personal or family history of serious illness. He is at the 50th percentile for height and 40th percentile for weight. His temperature is 36.9°C (98.4°F), pulse is 119/min, respirations are 32/min, and blood pressure is 135/85 mm Hg. A grade 2/6 systolic murmur is heard in the left paravertebral region. Pedal pulses are absent. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Low tissue oxygenation in the legs", "options": {"A": "Rib notching", "B": "Low tissue oxygenation in the legs", "C": "Interarm difference in blood pressure", "D": "Right ventricular outflow obstruction", "E": "Increased R wave amplitude in V5-V6 on ECG"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old man is brought to the emergency department because of syncope. He reports sudden onset of palpitations followed by loss of consciousness while carrying his groceries to his car. He is unable to recall any further details and does not have any chest pain or dizziness. He has a history of hypertension, type 2 diabetes mellitus, gastroparesis, and osteoarthritis of the knees. Medications include lisinopril, metformin, and ondansetron as needed for nausea. He also takes methadone daily for chronic pain. Apart from an abrasion on his forehead, he appears well. His temperature is 37.2 °C (98.9 F), heart rate is 104/min and regular, and blood pressure is 135/70 mm Hg. While he is in the emergency department, he loses consciousness again. Telemetry shows polymorphic ventricular tachycardia with cyclic alteration of the QRS axis that spontaneously resolves after 30 seconds. Results of a complete blood count, serum electrolyte concentrations, and serum thyroid studies show no abnormalities. Cardiac enzymes are within normal limits. Which of the following is the most likely underlying cause of this patient's syncope?", "answer": "Prolonged QT interval", "options": {"A": "Prolonged QT interval", "B": "Fast accessory conduction pathway", "C": "Prinzmetal angina", "D": "Brugada syndrome", "E": "Hypomagnesemia\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old man presents to the emergency department with nausea and vomiting. The patient started experiencing these symptoms shortly after arriving home from going out to eat at a seafood restaurant. His symptoms progressed and now he reports having an odd metallic taste in his mouth, diffuse pruritus, and blurry vision. His temperature is 99.0°F (37.2°C), blood pressure is 120/72 mmHg, pulse is 50/min, respirations are 17/min, and oxygen saturation is 99% on room air. Physical exam reveals bradycardia and an inability of the patient to differentiate hot versus cold; no rash can be appreciated on exam. Which of the following is the most likely etiology of this patient’s symptoms?", "answer": "Ciguatoxin", "options": {"A": "Ciguatoxin", "B": "Scombrotoxin", "C": "Tetrodotoxin", "D": "Type I hypersensitivity reaction", "E": "Viral gastroenteritis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 43-year-old man comes to the physician because of increasing shortness of breath for 1 month. He has been using two pillows at night but frequently wakes up feeling as if he is choking. Five months ago, he underwent surgery for creation of an arteriovenous fistula in his left upper arm. He has hypertension and chronic kidney disease due to reflux nephropathy. He receives hemodialysis three times a week. His current medications are enalapril, vitamin D3, erythropoietin, sevelamer, and atorvastatin. His temperature is 37.1°C (98.8°F), respirations are 22/min, pulse is 103/min and bounding, and blood pressure is 106/58 mm Hg. Examination of the lower extremities shows bilateral pitting pedal edema. There is jugular venous distention. A prominent thrill is heard over the brachiocephalic arteriovenous fistula. There are crackles heard at both lung bases. Cardiac examination shows an S3 gallop. The abdomen is soft and nontender. Which of the following is the most likely cause of this patient's symptoms?", "answer": "High-output heart failure", "options": {"A": "AV fistula aneurysm", "B": "Dialysis disequilibrium syndrome", "C": "Pulmonary embolism", "D": "Constrictive pericarditis", "E": "High-output heart failure"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 38-year-old woman, gravida 2, para 2, is brought to the emergency department by her husband after an episode of unconsciousness. She delivered a healthy infant two weeks ago and the postpartum course was complicated by severe vaginal bleeding, for which she required 4 units of packed red blood cells. Since the blood transfusion, she has had decreased milk production and has felt fatigued. Her pulse is 118/min and blood pressure is 104/63 mm Hg. Her finger-stick glucose concentration is 34 mg/dL. Serum thyroid-stimulating hormone and thyroxine levels are low and the serum sodium level is 132 mEq/L. Which of the following is the most likely cause of this patient's condition?", "answer": "Pituitary ischemia", "options": {"A": "Postpartum thyroiditis", "B": "Lactotrophic adenoma", "C": "Adrenal hemorrhage", "D": "Hypothalamic infarction", "E": "Pituitary ischemia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 71-year-old man is brought to the emergency department by his daughter after she found him to be extremely confused at home. She says that he appeared to be fine in the morning; however, upon returning home, she found that he was slumped in his chair and was hard to arouse. She was worried that he may have taken too many medications and rushed him to the emergency department. His past medical history is significant for bipolar disorder and absence seizures. He does not smoke and drinks 4 alcoholic beverages per night on average. On physical exam, he is found to have a flapping tremor of his hands, pitting ankle edema, and gynecomastia. He does not appear to have any focal neurologic deficits. Which of the following lab findings would most likely be seen in this patient?", "answer": "Increased prothrombin time", "options": {"A": "Increased anticonvulsant levels", "B": "Increased antidepressant levels", "C": "Increased bleeding time", "D": "Increased d-dimer levels", "E": "Increased prothrombin time"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 22-year-old man seeks help from a physician for his heroin addiction. He tells the doctor that he started using heroin at the age of 17 and gradually started increasing the dose. He has been trying to quit for the last 6 months after realizing the negative consequences of his addiction but has not succeeded because of the withdrawal symptoms. The physician suggests a drug that can be taken within a supervised rehabilitation program as a substitute for heroin to help alleviate withdrawal symptoms. The drug will then be tapered over time. He is further informed by the physician that this drug is not to be taken by the patient on his own and will not work in an emergency situation related to heroin withdrawal. Which of the following drugs is most likely to have been recommended by the physician?", "answer": "Methadone", "options": {"A": "Codeine", "B": "Clonidine", "C": "Methadone", "D": "Naloxone", "E": "Naltrexone"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old man is unable to pass urine after undergoing open abdominal surgery. His physical examination and imaging findings suggest that the cause of his urinary retention is non-obstructive and is most probably due to urinary bladder atony. He is prescribed a new selective muscarinic (M3) receptor agonist, which improves his symptoms. Which of the following is most likely involved in the mechanism of action of this new drug?", "answer": "Activation of phospholipase C", "options": {"A": "Inhibition of adenylyl cyclase", "B": "Inhibition of guanylyl cyclase", "C": "Activation of phospholipase C", "D": "Increased transmembrane K+ conductance", "E": "Increased transmembrane Na+ conductance"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old boy comes to the physician because of body aches and sore throat for 1 week. He has no history of serious illness and takes no medications. He lives with his parents; they recently adopted a cat from an animal shelter. He is sexually active with one female partner, and they use condoms consistently. His temperature is 38.7°C (101.7°F), pulse is 99/min, and blood pressure is 110/72 mm Hg. Examination shows bilateral posterior cervical lymphadenopathy. The pharynx is red and swollen. Laboratory studies show:\nHemoglobin 15 g/dL\nLeukocyte count 11,500/mm3\nSegmented neutrophils 48%\nBand forms 2%\nBasophils 0.5%\nEosinophils 1%\nLymphocytes 45%\nMonocytes 3.5%\nWhen the patient's serum is added to a sample of horse erythrocytes, the cells aggregate together. Which of the following is the most likely causal pathogen?\"", "answer": "Epstein-Barr virus", "options": {"A": "Epstein-Barr virus", "B": "Cytomegalovirus", "C": "Human immunodeficiency virus", "D": "Influenza virus", "E": "Toxoplasma gondii"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 8-year-old boy is brought to the emergency department with severe dyspnea, fatigue, and vomiting. His mother reports that he has been lethargic for the last several days with an increase in urine output. She thinks he may even be losing weight, despite eating and drinking more than normal for the last couple weeks. Laboratory results are notable for glucose of 440, potassium of 5.8, pH of 7.14 and HCO3 of 17. After administrating IV fluids and insulin, which of the following would you expect?", "answer": "Decrease in serum potassium", "options": {"A": "Increase in serum glucose", "B": "Increase in anion gap", "C": "Decrease in serum potassium", "D": "Decrease in pH", "E": "Decrease in serum bicarbonate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 49-year-old woman presents to the emergency room with bloody stool and malaise. She developed a fever and acute left lower quadrant abdominal pain earlier in the day. She has had 2 bowel movements with bright red blood. Her past medical history is notable for hyperlipidemia, hypertension, and diabetes mellitus. She takes lovastatin, hydrochlorothiazide, metformin, glyburide, and aspirin. Her temperature is 102.9°F (39.4°C), blood pressure is 101/61 mmHg, pulse is 110/min, and respirations are 22/min. On exam, she is fully alert and oriented. She is tender in the left lower quadrant. A computerized tomography (CT) scan is performed demonstrating acute diverticulitis. She is admitted and started on broad-spectrum antibiotics. 48 hours later, her urine output is significantly decreased. Her abdominal pain has improved but she has started vomiting and appears confused. She has new bilateral lower extremity edema and decreased breath sounds at the lung bases. Laboratory analysis upon admission and 48 hours later is shown below:\n\nAdmission:\nHemoglobin: 11.9 g/dl\nHematocrit: 34%\nLeukocyte count: 11,500/mm^3\nPlatelet count: 180,000/ mm^3\n\nSerum:\nNa+: 141 mEq/L\nCl-: 103 mEq/L\nK+: 4.5 mEq/L\nHCO3-: 23 mEq/L\nBUN: 21 mg/dL\nGlucose: 110 mg/dL\nCreatinine: 0.9 mg/dL\n\n48 hours later:\nHemoglobin: 10.1 g/dl\nHematocrit: 28%\nLeukocyte count: 11,500 cells/mm^3\nPlatelet count: 195,000/ mm^3\n\nSerum:\nNa+: 138 mEq/L\nCl-: 100 mEq/L\nK+: 5.1 mEq/L\nHCO3-: 24 mEq/L\nBUN: 30 mg/dL\nGlucose: 120 mg/dL\nCreatinine: 2.1 mg/dL\n\nWhich of the following findings would most likely be seen on urine microscopy?", "answer": "Muddy brown casts", "options": {"A": "Fatty casts", "B": "Hyaline casts", "C": "Muddy brown casts", "D": "Waxy casts", "E": "White blood cell casts"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old man is brought to the emergency department by his wife because of lethargy and confusion for the past 24 hours. He has also had a productive cough for the past year and has had a 10-kg (22-lb) weight loss over the past 6 months. He has a history of multiple sclerosis and has not had an acute exacerbation in over 10 years. For the past 30 years, he has smoked 2 packs of cigarettes daily. He drinks 2 beers every day after work. His temperature is 37.0°C (98.6°F), pulse is 90/min, blood pressure is 130/90 mm Hg, and respirations are 22/min. On examination, the patient appears lethargic and cannot state his name or his location. Physical examination reveals scattered wheezing bilaterally. Deep tendon reflexes cannot be elicited. Laboratory studies show:\nSerum\nNa+ 115 mEq/L\nK+ 4.5 mEq/L\nHCO3- 22 mEq/L\nGlucose 70 mg/dL\nBlood urea nitrogen 8 mg/dL\nUrine osmolality 450 mOsmol/kg H2O\nUrine sodium 70 mEq/L\nAn x-ray of the chest reveals a central lung mass. Which of the following is the next best step in management?\"", "answer": "Administer hypertonic saline", "options": {"A": "Order CT scan of the chest", "B": "Administer furosemide", "C": "Administer hypertonic saline", "D": "Administer demeclocycline", "E": "Administer conivaptan"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man presents to the physician with complaints of 5 days of watery diarrhea, fever, and bloating. He has not noticed any blood in his stool. He states that his diet has not changed recently, and his family has been spared from diarrhea symptoms despite eating the same foods that he has been cooking at home. He has no history of recent travel outside the United States. His only medication is high-dose omeprazole, which he has been taking daily for the past few months to alleviate his gastroesophageal reflux disease (GERD). Which of the following is the most appropriate initial test to work up this patient’s symptoms?", "answer": "Stool toxin assay", "options": {"A": "Colonoscopy", "B": "Fecal occult blood test", "C": "Stool culture", "D": "Stool ova and parasite", "E": "Stool toxin assay"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 49-year-old woman presents to her primary care doctor in late December with malaise. She reports worsening fatigue, myalgias, headache, and malaise that started 1 day ago. She works as a lunch lady at an elementary school. Her past medical history is notable for a distal radius fracture after a fall 2 years ago, but she is otherwise healthy and takes no medications. She does not smoke or drink alcohol. She is married and has 3 adult children who are healthy. Her temperature is 102.9°F (39.4°C), blood pressure is 101/61 mmHg, pulse is 112/min, and respirations are 21/min. On exam, she appears lethargic and uncomfortable but is able to answer questions appropriately. Breath sounds are normal bilaterally. She is started on intravenous fluids and a pharmacologic agent for treatment. Which of the following is the most likely mechanism of action of the drug being used to treat this patient?", "answer": "Neuraminidase inhibitor", "options": {"A": "DNA polymerase inhibitor", "B": "Neuraminidase inhibitor", "C": "Protease inhibitor", "D": "Reverse transcriptase inhibitor", "E": "RNA-dependent polymerase inhibitor"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 78-year-old woman is brought to the emergency ward by her son for lethargy and generalized weakness. The patient speaks in short utterances and does not make eye contact with the provider or her son throughout the interview and examination. You elicit that the patient lives with her son and daughter-in-law, and she reports vague weakness for the last couple days. The emergency room provider notices 3-4 healing bruises on the patient's upper extremities; otherwise, examination is not revealing. Routine chemistries and blood counts are unremarkable; non-contrast head CT demonstrates normal age-related changes. Which of the following is the most appropriate next step in management?", "answer": "Ask the patient's son to leave the room", "options": {"A": "Perform lumbar puncture", "B": "Question the patient regarding abuse or neglect", "C": "Question the patient's son regarding the home situation", "D": "Ask the patient's son to leave the room", "E": "Call Adult Protective Services to report the patient's son"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman presents with fever, chills, nausea, and urinary urgency and frequency. She says that her symptoms began 4 days ago and have progressively worsened. Her past medical history is significant for a 6-month history of recurrent urinary tract infections (UTIs). Her vital signs include: temperature 39.0°C (102.2°F), blood pressure 100/70 mm Hg, pulse 92/min, and respiratory rate 25/min. On physical examination, there is moderate left costovertebral angle tenderness. Laboratory findings are significant for the following:\nWBC 8,500/mm3\nRBC 4.20 x 106/mm3\nHematocrit 41.5%\nHemoglobin 13.0 g/dL\nPlatelet count 225,000/mm3\nUrinalysis\nColor Dark yellow\nClarity Turbid\npH 6.5\nSpecific gravity 1.026\nGlucose None\nKetones None\nNitrites Positive\nLeukocyte esterase Positive\nBilirubin Negative\nUrobilirubin 0.6 mg/dL\nProtein Trace\nBlood None\nWBC 25/hpf\nBacteria Many\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Pyelonephritis", "options": {"A": "Pyelonephritis", "B": "Uncomplicated cystitis", "C": "Complicated cystitis", "D": "UTI", "E": "Acute obstructing nephrolithiasis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 44-year-old man comes to the physician because of a 2-week history of lower extremity swelling and frothy urine. He has a history of chronic hepatitis C infection. Physical examination shows 3+ pitting edema of the lower legs and ankles. Further evaluation of this patient is most likely to show which of the following?", "answer": "Increased lipoproteins", "options": {"A": "Decreased blood urea nitrogen", "B": "Decreased cholesterol", "C": "Increased lipoproteins", "D": "Decreased cystatin C", "E": "Increased antithrombin III"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old male presents to his primary care physician complaining of increased urinary frequency and a weakened urinary stream. He has a history of gout, obesity, diabetes mellitus, and hyperlipidemia. He currently takes allopurinol, metformin, glyburide, and rosuvastatin. His temperature is 98.6°F (37°C), blood pressure is 130/85 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination reveals an enlarged, non-tender prostate without nodules or masses. An ultrasound reveals a uniformly enlarged prostate that is 40mL in size. His physician starts him on a new medication. After taking the first dose, the patient experiences lightheadedness upon standing and has a syncopal event. Which of the following mechanisms of action is most consistent with the medication in question?", "answer": "Alpha-1-adrenergic receptor antagonist", "options": {"A": "Dihydropyridine calcium channel blocker", "B": "Alpha-1-adrenergic receptor antagonist", "C": "Alpha-2-adrenergic receptor agonist", "D": "Non-selective alpha receptor antagonist", "E": "Selective muscarinic agonist"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 39-year-old male presents with muscle weakness in his upper and lower extremities. The patient has also noticed some trouble with swallowing. On physical exam, signs of hyperreflexia, spasticity, fasciculations, and muscle atrophy are present in an asymmetric fashion. Tongue fasciculations are also present. No sensory loss is noted. The patient does not report any abnormality with his bowel or bladder function. What will most likely be found on muscle biopsy?", "answer": "Denervation and reinnervation of the muscle", "options": {"A": "Mitochondrial proliferation leading to ragged appearance in Gomori trichrome stain", "B": "Perimysial CD4+ infiltration and perifascicular atrophy", "C": "CD8+ infiltrating within the fascicle", "D": "Denervation and reinnervation of the muscle", "E": "Larval cysts"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 38-year-old woman comes to the physician for a follow-up examination. She was diagnosed with immune thrombocytopenic purpura at the age of 37 years and has been treated with glucocorticoids and intravenous immune globulin. She has visited the emergency department 3 times in the past 4 months for nose bleeds, which required cauterization. Her platelet counts on her previous visits were 18,320/mm3, 17,500/mm3, and 19,100/mm3. Current medications include dexamethasone and a multivitamin. She has no children. Her immunizations are up-to-date. Vital signs are within normal limits. Examination shows petechiae on the bilateral lower extremities. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender; there is no organomegaly. Her hemoglobin concentration is 13.3 g/dL, leukocyte count is 8,100/mm3, and platelet count is 13,000/mm3. Her blood type is A negative. Serology for hepatitis C and HIV is negative. Which of the following is the most appropriate next step in management?", "answer": "Schedule splenectomy", "options": {"A": "Romiplostim therapy", "B": "Rituximab therapy", "C": "Danazol therapy", "D": "Observation and follow-up", "E": "Schedule splenectomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 54-year-old man is brought to the physician by his wife because of progressive difficulty walking during the past 3 months. He has not been able to walk without assistance for the past month and has started to use a wheelchair. He also reports having urinary incontinence for 1 year. His wife says that he has begun to slur his words and has become very difficult to understand. His temperature is 37.0°C (98.6°F), pulse is 70/min, and respirations are 16/min. His blood pressure is 130/80mm Hg while sitting and 110/65mm Hg when standing. He is oriented to person and place but not to time. Neurological examination shows a mild tremor in his right hand and rigidity in his upper and lower extremities. He is unable to perform repetitive rotary forearm movements. Which of the following is the most likely diagnosis?", "answer": "Multiple system atrophy", "options": {"A": "Multiple system atrophy", "B": "Parkinson disease", "C": "Friedreich ataxia", "D": "Corticobasal degeneration", "E": "Normal pressure hydrocephalus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old primigravid woman at 36 weeks' gestation comes to the emergency department for 2 hours of contractions. Her pregnancy has been uncomplicated. The contractions occur once every 20–30 minutes, last less than 30 seconds, and have been consistent in intensity and duration since onset. During that time there has been an increase in fetal movements. Her temperature is 37.1°C (98.8°F), pulse is 98/min, and blood pressure is 104/76 mm Hg. Pelvic examination shows clear cervical mucus and a firm uterus consistent in size with a 36-week gestation. The cervix is 0% effaced and undilated; the vertex is at -3 station. The fetal heart rate is reassuring. After an hour of monitoring in the emergency department, the character of the contractions and pelvic examination findings remain unchanged. Which of the following is the most appropriate next step?", "answer": "Reassurance and discharge", "options": {"A": "Administer tocolytics", "B": "Offer local or regional anesthesia", "C": "Admit for continuous monitoring", "D": "Reassurance and discharge", "E": "Perform cesarean delivery"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old woman is brought to the emergency department by a friend after fainting at work and hitting her head. She is conscious, alert, and in pain as she sustained a deep laceration above her right orbit. When asked about prior fainting episodes, she says that she has had them since childhood, but she felt it was \"nothing serious\". She also says she has frequent palpitations, shortness of breath, nausea, and, at times, chest pain and attributes this to \"working too hard.\" Her pulse is 110/min, respirations are 20/min, temperature is 37.4°C (99.3°F), and blood pressure is 110/78 mm Hg. Physical examination shows tachycardia and mild hypotension. The patient's electrocardiogram is obtained. Which of the following drugs is the preferable choice for first line treatment of the patient's condition?", "answer": "Magnesium sulfate", "options": {"A": "Calcium gluconate", "B": "Epinephrine", "C": "Flecainide", "D": "Magnesium sulfate", "E": "Procainamide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 61-year-old G4P3 presents with a 5-year history of involuntary urine loss on coughing, sneezing, and physical exertion. She denies urine leakage at night. She has been menopausal since 51 years of age. She is otherwise healthy and is not on any medications, including hormone replacement therapy. The weight is 78 kg (172 lb) and the height is 156 cm (5.1 ft). The vital signs are within normal limits. The physical examination shows no costovertebral angle tenderness. The neurologic examination is unremarkable. The gynecologic examination revealed pale and thin vulvar and vaginal mucosa. The external urethral opening appears normal; there is urine leakage when the patient is asked to cough. The Q-tip test is positive. The bimanual exam reveals painless bulging of the anterior vaginal wall. Which of the following findings are most likely to be revealed by cystometry?", "answer": "Normal residual volume, no involuntary detrusor contractions", "options": {"A": "Normal residual volume, involuntary detrusor contractions on maximal bladder filling", "B": "Increased residual volume, no involuntary detrusor contractions", "C": "Normal residual volume, involuntary detrusor contractions on minimal bladder filling", "D": "Increased residual volume, involuntary detrusor contractions on maximal bladder filling", "E": "Normal residual volume, no involuntary detrusor contractions"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 20-year-old woman is brought in by police for trying to break into a museum after hours. The patient states that she is a detective on the trail of a master collusion scheme and needs the artifacts from the museum to prove her case. Her family reports that she has been acting strangely for the past week. She has been up perusing the internet all night without taking breaks. Her husband states that she has had increased sexual interest for the past week; however, he did not report this to the physician when he first noticed it. The patient is unable to offer a history as she cannot be redirected from her current theory. Her temperature is 99.0°F (37.2°C), blood pressure is 122/81 mmHg, pulse is 97/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable only for a highly-energized patient. Laboratory studies are ordered as seen below.\n\nUrine:\nColor: Yellow\nNitrite: Negative\nBacteria: Negative\nLeukocytes: Negative\nhCG: Positive\nBenzodiazepines: Negative\nBarbiturate: Negative\nCocaine: Negative\nAcetaminophen: Negative\n\nWhich of the following is the most appropriate next step in management?", "answer": "Haloperidol", "options": {"A": "Electroconvulsive therapy", "B": "Fluoxetine", "C": "Haloperidol", "D": "Lithium", "E": "Valproic acid"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Six hours after delivery, a 3050-g (6-lb 12-oz) male newborn is noted to have feeding intolerance and several episodes of bilious vomiting. He was born at term to a healthy 35-year-old woman following a normal vaginal delivery. The pregnancy was uncomplicated, but the patient's mother had missed several of her prenatal checkups. The patient's older brother underwent surgery for pyloric stenosis as an infant. Vital signs are within normal limits. Physical examination shows epicanthus, upward slanting of the eyelids, low-set ears, and a single transverse palmar crease. The lungs are clear to auscultation. A grade 2/6 holosystolic murmur is heard at the left mid to lower sternal border. Abdominal examination shows a distended upper abdomen and a concave-shaped lower abdomen. There is no organomegaly. An x-ray of the abdomen is shown. Which of the following is the most likely diagnosis?", "answer": "Duodenal atresia", "options": {"A": "Necrotizing enterocolitis", "B": "Duodenal atresia", "C": "Hirschsprung's disease", "D": "Hypertrophic pyloric stenosis", "E": "Meconium ileus"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A researcher is examining the relationship between socioeconomic status and IQ scores. The IQ scores of young American adults have historically been reported to be distributed normally with a mean of 100 and a standard deviation of 15. Initially, the researcher obtains a random sampling of 300 high school students from public schools nationwide and conducts IQ tests on all participants. Recently, the researcher received additional funding to enable an increase in sample size to 2,000 participants. Assuming that all other study conditions are held constant, which of the following is most likely to occur as a result of this additional funding?", "answer": "Decrease in standard error of the mean", "options": {"A": "Increase in range of the confidence interval", "B": "Decrease in standard deviation", "C": "Decrease in standard error of the mean", "D": "Increase in risk of systematic error", "E": "Increase in probability of type II error"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year-old male presents to his primary care physician complaining of pain with urination and eye redness. He reports that he developed these symptoms approximately one week ago. He also has noticed left knee and right heel pain that started a few days ago. He denies any recent trauma. He had an episode of abdominal pain and diarrhea ten days ago that resolved. He has otherwise felt well. On exam, he walks with a limp and his conjunctivae are erythematous. Laboratory findings are notable for an elevated erythrocyte sedimentation rate (ESR) and elevated C-reactive protein (CRP). Which of the following is most likely associated with this patient’s condition?", "answer": "HLA-B27 haplotype", "options": {"A": "HLA-B27 haplotype", "B": "HLA-DR4 haplotype", "C": "Anti-cyclic citrullinated peptide (anti-CCP) antibody", "D": "Anti-centromere antibody", "E": "Rheumatoid factor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old boy is brought to the pediatrician by his mother for a routine medical examination. His medical history is relevant for delayed gross motor milestones. The mother is concerned about a growth delay because both of his brothers were twice his size at this age. Physical examination reveals a well-groomed and healthy boy with a prominent forehead and short stature, in addition to shortened upper and lower extremities with a normal vertebral column. The patient’s vitals reveal: temperature 36.5°C (97.6°F); pulse 60/min; and respiratory rate 17/min and a normal intelligence quotient (IQ). A mutation in which of the following genes is the most likely cause underlying the patient’s condition?", "answer": "Fibroblast growth factor receptor 3", "options": {"A": "Alpha-1 type I collagen", "B": "Fibrillin-1", "C": "Fibroblast growth factor receptor 3", "D": "Insulin-like growth factor 1 receptor", "E": "Runt-related transcription factor 2"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An investigator is studying brachial artery reactivity in women with suspected coronary heart disease. The brachial artery diameter is measured via ultrasound before and after intra-arterial injection of acetylcholine. An increase of 7% in the vascular diameter is noted. The release of which of the following is most likely responsible for the observed effect?", "answer": "Nitric oxide from endothelial cells", "options": {"A": "Nitric oxide from endothelial cells", "B": "Endothelin from the peripheral vasculature", "C": "Serotonin from neuroendocrine cells", "D": "Norepinephrine from the adrenal medulla", "E": "Atrial natriuretic peptide from atrial myocytes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old female in the 2nd trimester of pregnancy is diagnosed with primary Toxoplasma gondii infection. Her physician fears that the fetus may be infected in utero. Which of the following are associated with T. gondii infection in neonates?", "answer": "Hydrocephalus, chorioretinitis, intracranial calcifications", "options": {"A": "Patent ductus arteriosus, cataracts, deafness", "B": "Temporal encephalitis, vesicular lesions", "C": "Hutchinson’s teeth, saddle nose, short maxilla", "D": "Deafness, seizures, petechial rash", "E": "Hydrocephalus, chorioretinitis, intracranial calcifications"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old man comes to the physician because of a swollen and painful right knee for the last 3 days. He has no history of joint disease. His vital signs are within normal limits. Examination shows erythema and swelling of the right knee, with limited range of motion due to pain. Arthrocentesis of the right knee joint yields 7 mL of cloudy fluid with a leukocyte count of 29,000/mm3 (97% segmented neutrophils). Compensated polarized light microscopy of the aspirate is shown. Which of the following is the most likely underlying mechanism of this patient's knee pain?", "answer": "Calcium pyrophosphate deposition", "options": {"A": "Bacterial infection of the joint", "B": "Calcium pyrophosphate deposition", "C": "Mechanical stress and trauma", "D": "Immune complex-mediated cartilage destruction", "E": "Monosodium urate deposition"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A new treatment for hemorrhagic stroke, which is a life-threatening clinical condition that occurs when a diseased blood vessel in the brain ruptures or leaks, was evaluated as soon as it hit the market by an international group of neurology specialists. In those treated with the new drug, a good outcome was achieved in 30%, while those treated with the current standard of care had a good outcome in just 10% of cases. The clinicians involved in this cohort study concluded that the newer drug is more effective and prompted for urgent changes in the guidelines addressing hemorrhagic stroke incidents. According to the aforementioned percentages, how many patients must be treated with the new drug to see 1 additional good outcome?", "answer": "5", "options": {"A": "5", "B": "10", "C": "15", "D": "20", "E": "30"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old man is brought to the emergency department 1 hour after the sudden onset of shortness of breath, epigastric pain, and sweating. He has no history of similar symptoms. He has hypertension and type 2 diabetes mellitus. Current medications include amlodipine and metformin. He has smoked one pack of cigarettes daily for 20 years. He appears weak and pale. His pulse is 56/min, respirations are 18/min, and blood pressure is 100/70 mm Hg. Cardiac examination shows normal heart sounds. The lungs are clear to auscultation. The skin is cold to the touch. An ECG is shown. Bedside transthoracic echocardiography shows normal left ventricular function. High-dose aspirin is administered. Administration of which of the following is most appropriate next step in management?", "answer": "Normal saline bolus\n\"", "options": {"A": "Intravenous atropine", "B": "Intravenous morphine", "C": "Sublingual nitroglycerin", "D": "Phenylephrine infusion", "E": "Normal saline bolus\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An investigator studying targeted therapy in patients with gastrointestinal stromal tumors requires a reliable test to determine the spatial distribution of CD117-positive cells in biopsy specimens. Which of the following is the most appropriate test?", "answer": "Immunohistochemistry", "options": {"A": "Flow cytometry", "B": "Immunohistochemistry", "C": "Western blot", "D": "Northern blot", "E": "Fluorescence in-situ hybridization\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "In an attempt to create other selective dopamine 1 (D1) agonists, a small pharmaceutical company created a cell-based chemical screen that involved three modified receptors - alpha 1 (A1), beta 1 (B1), and D1. In the presence of D1 stimulation, the cell would produce an mRNA that codes for a fluorescent protein; however, if the A1 or B1 receptors are also stimulated at the same time, the cells would degrade the mRNA of the fluorescent protein thereby preventing it from being produced. Which of the following would best serve as a positive control for this experiment?", "answer": "Fenoldopam", "options": {"A": "Bromocriptine", "B": "Dobutamine", "C": "Dopamine", "D": "Epinephrine", "E": "Fenoldopam"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 56-year-old woman comes to the physician because of a 2-year-history of intermittent upper abdominal pain that occurs a few hours after meals and occasionally wakes her up in the middle of the night. She reports that the pain is relieved with food intake. Physical examination shows no abnormalities. Endoscopy shows a 0.5 x 0.5 cm ulcer on the posterior wall of the duodenal bulb. A biopsy specimen obtained from the edge of the ulcer shows hyperplasia of submucosal glandular structures. Hyperplasia of these cells most likely results in an increase of which of the following?", "answer": "Bicarbonate secretion", "options": {"A": "Glycoprotein synthesis", "B": "Antigen presentation", "C": "Lysozyme secretion", "D": "Hydrochloric acid secretion", "E": "Bicarbonate secretion"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "The balance between glycolysis and gluconeogenesis is regulated at several steps, and accumulation of one or more products/chemicals can either promote or inhibit one or more enzymes in either pathway. Which of the following molecules if increased in concentration can promote gluconeogenesis?", "answer": "Acetyl-CoA", "options": {"A": "AMP", "B": "ADP", "C": "Insulin", "D": "Fructose-2,6-biphosphate", "E": "Acetyl-CoA"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old man who had undergone liver transplantation 7 years ago, presents to the physician because of yellowish discoloration of the skin, sclera, and urine. He is on regular immunosuppressive therapy and is well-adherent to the treatment. He has no comorbidities and is not taking any other medication. He provides a history of similar episodes of yellowish skin discoloration 6–7 times since he underwent liver transplantation. Physical examination shows clinical jaundice. Laboratory studies show:\nWhile blood cell (WBC) count 4,400/mm3\nHemoglobin 11.1 g/dL\nSerum creatinine 0.9 mg/dL\nSerum bilirubin (total) 44 mg/dL\nAspartate transaminase (AST) 1,111 U/L\nAlanine transaminase (ALT) 671 U/L\nSerum gamma-glutamyl transpeptidase 777 U/L\nAlkaline phosphatase 888 U/L\nProthrombin time 17 seconds\nA Doppler ultrasound shows significantly reduced blood flow into the transplanted liver. A biopsy of the transplanted liver is likely to show which of the following histological features?", "answer": "Interstitial cellular infiltration with parenchymal fibrosis, obliterative arteritis", "options": {"A": "Normal architecture of bile ducts and hepatocytes", "B": "Broad fibrous septations with formation of micronodules", "C": "Ballooning degeneration of hepatocytes", "D": "Irregularly shaped nodules of regenerating hepatocytes with peripheral halo", "E": "Interstitial cellular infiltration with parenchymal fibrosis, obliterative arteritis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 14-year-old girl is brought to the physician after she accidentally cut her right forearm earlier that morning while working with her mother's embroidery scissors. She has no history of serious illness. The mother says she went to elementary and middle school abroad and is not sure if she received all of her childhood vaccinations. She appears healthy. Her temperature is 37°C (98.6 °F), pulse 90/min, and blood pressure is 102/68 mm Hg. Examination shows a clean 2-cm laceration on her right forearm with surrounding edema. There is no erythema or discharge. The wound is irrigated with water and washed with soap. Which of the following is the most appropriate next step in management?", "answer": "Administer Tdap only", "options": {"A": "Administer DTaP only", "B": "Intravenous metronidazole", "C": "Administer Tdap only", "D": "Administer TIG only", "E": "No further steps are necessary"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old woman comes to the physician because of a 3-day history of a sore throat and fever. Her temperature is 38.5°C (101.3°F). Examination shows edematous oropharyngeal mucosa and enlarged tonsils with purulent exudate. There is tender cervical lymphadenopathy. If left untreated, which of the following conditions is most likely to occur in this patient?", "answer": "Dilated cardiomyopathy", "options": {"A": "Toxic shock syndrome", "B": "Polymyalgia rheumatica", "C": "Rheumatoid arthritis", "D": "Dilated cardiomyopathy", "E": "Erythema multiforme"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old man comes to his primary care provider because of double vision and headache. He says these symptoms developed suddenly last night and have not improved. He has had type 2 diabetes mellitus for 32 years and essential hypertension for 19 years for which he takes metformin and lisinopril. His last recorded A1c was 9.4%. He has smoked 10 to 15 cigarettes a day for the past 35 years. Family history is significant for chronic kidney disease in his mother. Vital signs reveal a temperature of 36.9 °C (98.42°F), blood pressure of 137/82 mm Hg, and pulse of 72/min. On examination, there is ptosis of the right eye and it is deviated down and out. Visual acuity is not affected in either eye. Which of the following cranial nerves is most likely impaired in this patient?", "answer": "Oculomotor nerve", "options": {"A": "Trochlear nerve", "B": "Oculomotor nerve", "C": "Abducens nerve", "D": "Optic nerve", "E": "Facial nerve"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3-year-old boy is brought to the emergency department with abdominal pain. His father tells the attending physician that his son has been experiencing severe stomach aches over the past week. They are intermittent in nature, but whenever they occur he cries and draws up his knees to his chest. This usually provides some relief. The parents have also observed mucousy stools and occasional bloody stools that are bright red with blood clots. They tell the physician that their child has never experienced this type of abdominal pain up to the present. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. On physical exam, his vitals are generally normal with a slight fever and mild tachycardia. The boy appears uncomfortable. An abdominal exam reveals a sausage-shaped mass in the right upper abdomen. Which of the following is the most common cause of these symptoms?", "answer": "Idiopathic", "options": {"A": "Meckel's diverticulum", "B": "Enlarged mesenteric lymph node", "C": "Gastrointestinal infection", "D": "Henoch-Schonlein purpura", "E": "Idiopathic"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 51-year-old man presents complaining of decreased vibratory sense in his lower limbs. Physical exam reveals a widened pulse pressure and a decrescendo murmur occurring after the S2 heart sound. After further questioning, he also reports he experienced a maculopapular rash over his trunk, palms and soles many years ago that resolved on its own. In order to evaluate the suspected diagnosis, the physician FIRST tested for which of the following?", "answer": "Agglutination of antibodies with beef cardiolipin", "options": {"A": "Agglutination of antibodies with beef cardiolipin", "B": "Indirect immunofluoresence of the patient’s serum and killed T. palladium", "C": "Cytoplasmic inclusions on Giemsa stain", "D": "Agglutination of patients serum with Proteus O antigens", "E": "Gram negative, oxidase positive, comma shaped bacteria growing at 42 degrees C"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman comes to the physician for genetic counseling prior to conception. For the past year, she has had intermittent episodes of headache, nausea, abdominal pain, and tingling of her fingers. She also complains of dark urine during the episodes. Her mother and maternal uncle have similar symptoms and her father is healthy. Her husband is healthy and there is no history of serious illness in his family. Serum studies show elevated concentrations of porphobilinogen and δ-aminolevulinic acid. What is the probability of this patient having a child with the same disease as her?", "answer": "50%", "options": {"A": "67%", "B": "50%", "C": "25%", "D": "100%", "E": "0%"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Three days after undergoing cardiac catheterization and coronary angioplasty for acute myocardial infarction, a 70-year-old man develops shortness of breath at rest. He has hypertension, hyperlipidemia, and type 2 diabetes mellitus. His current medications include aspirin, clopidogrel, atorvastatin, sublingual nitroglycerin, metoprolol, and insulin. He appears diaphoretic. His temperature is 37°C (98.6°F), pulse is 120/min, respirations are 22/min, and blood pressure is 100/55 mm Hg. Crackles are heard at both lung bases. Cardiac examination shows a new grade 3/6 holosystolic murmur heard best at the cardiac apex. An ECG shows sinus rhythm with T wave inversion in leads II, III, and aVF. Which of the following is the most likely explanation for this patient's symptoms?", "answer": "Papillary muscle rupture", "options": {"A": "Early infarct-associated pericarditis", "B": "Ventricular septal rupture", "C": "Postmyocardial infarction syndrome", "D": "Coronary artery dissection", "E": "Papillary muscle rupture"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An investigator is studying the mechanism of HIV infection in cells obtained from a human donor. The effect of a drug that impairs viral fusion and entry is being evaluated. This drug acts on a protein that is cleaved off of a larger glycosylated protein in the endoplasmic reticulum of the host cell. The protein that is affected by the drug is most likely encoded by which of the following genes?", "answer": "env", "options": {"A": "rev", "B": "gag", "C": "pol", "D": "env", "E": "tat"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 54-year-old man comes to the physician for a follow-up examination. One week ago, he was treated in the emergency department for chest pain, palpitations, and dyspnea. As part of his regimen, he was started on a medication that irreversibly inhibits the synthesis of thromboxane A2 and prostaglandins. Which of the following is the most likely adverse effect of this medication?", "answer": "Gastrointestinal hemorrhage", "options": {"A": "Chronic rhinosinusitis", "B": "Acute interstitial nephritis", "C": "Gout attack", "D": "Tinnitus", "E": "Gastrointestinal hemorrhage"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 66-year-old man undergoes a coronary artery bypass grafting. Upon regaining consciousness, he reports that he cannot see from either eye and cannot move his arms. Physical examination shows bilaterally equal, reactive pupils. A fundoscopy shows no abnormalities. An MRI of the brain shows wedge-shaped cortical infarcts in both occipital lobes. Which of the following is the most likely cause of this patient's current symptoms?", "answer": "Systemic hypotension\n\"", "options": {"A": "Amyloid angiopathy", "B": "Lipohyalinosis", "C": "Cardiac embolism", "D": "Atherothrombosis", "E": "Systemic hypotension\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 74-year-old man presents to the emergency room with abdominal pain. He reports acute onset of left lower quadrant abdominal pain and nausea three hours prior to presentation. The pain is severe, constant, and non-radiating. He has had two maroon-colored bowel movements since the pain started. His past medical history is notable for hypertension, hyperlipidemia, atrial fibrillation, insulin-dependent diabetes mellitus, and rheumatoid arthritis. He takes lisinopril, hydrochlorothiazide, atorvastatin, dabigatran, methotrexate. He has a 60 pack-year smoking history and drinks 1-2 beers per day. He admits to missing some of his medications recently because he was on vacation in Hawaii. His last colonoscopy was 4 years ago which showed diverticular disease in the descending colon and multiple sessile polyps in the sigmoid colon which were removed. His temperature is 100.1°F (37.8°C), blood pressure is 145/85 mmHg, pulse is 100/min, and respirations are 20/min. On exam, he has notable abdominal distention and is exquisitely tender to palpation in all four abdominal quadrants. Bowel sounds are absent. Which of the following is the most likely cause of this patient’s condition?", "answer": "Cardiac thromboembolism", "options": {"A": "Cardiac thromboembolism", "B": "Duodenal compression", "C": "Perforated intestinal mucosal herniation", "D": "Paradoxical thromboembolism", "E": "Splanchnic vasoconstriction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old boy is brought to the physician by his father because of a 1-day history of a pruritic rash on his trunk and face. Five days ago, he developed low-grade fever, nausea, and diarrhea. Physical examination shows a lace-like erythematous rash on the trunk and face with circumoral pallor. The agent most likely causing symptoms in this patient has selective tropism for which of the following cells?", "answer": "Erythroid progenitor cells", "options": {"A": "Epithelial cells", "B": "T lymphocytes", "C": "Erythroid progenitor cells", "D": "Sensory neuronal cells", "E": "Monocytes\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 43-year-old woman presents to your clinic for the evaluation of an abnormal skin lesion on her forearm. The patient is worried because her mother passed away from melanoma. You believe that the lesion warrants biopsy for further evaluation for possible melanoma. Your patient is concerned about her risk for malignant disease. What is the most important prognostic factor of melanoma?", "answer": "Depth of invasion of atypical cells", "options": {"A": "S-100 tumor marker present", "B": "Evolution of lesion over time", "C": "Age at presentation", "D": "Depth of invasion of atypical cells", "E": "Level of irregularity of the borders"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old woman presents to her physician for her annual checkup. She has diabetes mellitus, type 1 and takes insulin regularly. She reports no incidents of elevated or low blood sugar and that she is feeling energetic and ready to face the morning every day. Her vital signs and physical are normal. On the way home from her checkup she stops by the pharmacy and picks up her prescription of insulin. Later that night she takes a dose. What is the signaling mechanism associated with this medication?", "answer": "Activation of tyrosine kinase", "options": {"A": "Increased permeability of the cell membrane to positively charged molecules", "B": "Increased permeability of the cell membrane to negatively charged molecules", "C": "Activation of tyrosine kinase", "D": "Increased concentration intracellular cAMP", "E": "Rapid and direct upregulation of enzyme transcription"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old girl comes to the physician because of excessive flow and duration of her menses. Since menarche a year ago, menses have occurred at irregular intervals and lasted 8–9 days. Her last menstrual period was 5 weeks ago with passage of clots. She has no family or personal history of serious illness and takes no medications. She is at the 50th percentile for height and 20th percentile for weight. Physical examination shows no abnormalities. A urine pregnancy test is negative. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Inadequate gonadotropin production", "options": {"A": "Embryonal rhabdomyosarcoma", "B": "Endometrial polyp", "C": "Inadequate gonadotropin production", "D": "Defective von Willebrand factor", "E": "Excessive androgen production"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 3-week-old boy is brought to the pediatrician by his parents for a circumcision. The circumcision was uncomplicated; however, after a few hours, the diaper contained blood, and the bleeding has not subsided. A complete blood count was ordered, which was significant for a platelet count of 70,000/mm3. On peripheral blood smear, the following was noted (figure A). The prothrombin time was 12 seconds, partial thromboplastin time was 32 seconds, and bleeding time was 13 minutes. On platelet aggregation studies, there was no response with ristocetin. This result was not corrected with the addition of normal plasma. There was a normal aggregation response with the addition of ADP. Which of the following is most likely true of this patient's underlying disease?", "answer": "Decreased GpIb", "options": {"A": "Decreased GpIIb/IIIa", "B": "Adding epinephrine would not lead to platelet aggregation", "C": "Responsive to desmopressin", "D": "Decreased GpIb", "E": "Protein C resistance"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old man presents to the emergency department with shortness of breath. He was eating dinner with his family during the holidays and felt very short of breath, thus prompting him to come in. The patient has a past medical history of diabetes, hypertension, 2 myocardial infarctions, and obesity. Physical exam is notable for bilateral pulmonary crackles and a jugular venous distension. Chest radiography reveals an enlarged cardiac silhouette and blunting of the costophrenic angles. The patient is started on a medication for his acute symptoms. Two hours later, he states his symptoms have vastly improved and repeat chest radiography is notable for an enlarged cardiac silhouette. Which of the following is a property of the medication most likely given?", "answer": "Chronic use leads to long-term nephrogenic adaptations", "options": {"A": "Can lead to respiratory depression", "B": "Causes venodilation and a decrease in preload", "C": "Increases cardiac contractility and afterload", "D": "Increases cardiac contractility and decreases afterload", "E": "Chronic use leads to long-term nephrogenic adaptations"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 47-year-old woman presents to her physician for difficulty swallowing. She states that she intentionally delayed seeing a physician for this issue. She says her primary issue with swallowing is that her mouth always feels dry so she has difficulty chewing food to the point that it can be swallowed. On physical examination, her oral mucosa appears dry. Both of her eyes also appear dry. Several enlarged lymph nodes are palpated. Which of the following patterns of reactive lymphadenitis is most commonly associated with this patient’s presentation?", "answer": "Follicular hyperplasia", "options": {"A": "Sinus hyperplasia", "B": "Follicular hyperplasia", "C": "Paracortical hyperplasia", "D": "Diffuse hyperplasia", "E": "Mixed B and T cell hyperplasia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old female is admitted to the hospital after worsening headaches for the past month. She has noticed that the headaches are usually generalized, and frequently occur during sleep. She does not have a history of migraines or other types of headaches. Her past medical history is significant for breast cancer, which was diagnosed a year ago and treated with mastectomy. She recovered fully and returned to work shortly thereafter. CT scan of the brain now shows a solitary cortical 5cm mass surrounded by edema in the left hemisphere of the brain at the grey-white matter junction. She is admitted to the hospital for further management. What is the most appropriate next step in management for this patient?", "answer": "Surgical resection of the mass", "options": {"A": "Chemotherapy", "B": "Seizure prophylaxis and palliative pain therapy", "C": "Irradiation to the breasts", "D": "Irradiation to the brain mass", "E": "Surgical resection of the mass"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old woman comes to the physician because of progressive weakness. She has noticed increasing difficulty performing household chores and walking her dog over the past month. Sometimes she feels too fatigued to cook dinner. She has noticed that she feels better after sleeping. She does not have chest pain, shortness of breath, or a history of recent illness. She has no personal history of serious illness and takes no medications. She has smoked two packs of cigarettes daily for 25 years. She appears fatigued. Her temperature is 37°C (98.8°F), pulse is 88/min, and blood pressure is 148/80 mm Hg. Pulse oximetry shows an oxygen saturation of 98% in room air. Bilateral expiratory wheezes are heard at both lung bases. Examination shows drooping of the upper eyelids. There is diminished motor strength in her upper extremities. Her sensation and reflexes are intact. A treatment with which of the following mechanisms of action is most likely to be effective?", "answer": "Inhibition of acetylcholinesterase", "options": {"A": "Inhibition of acetylcholinesterase", "B": "Stimulation of B2 adrenergic receptors", "C": "Removing autoantibodies, immune complexes, and cytotoxic constituents from serum", "D": "Reactivation of acetylcholinesterase", "E": "Competitive blocking of the muscarinic receptor"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator is studying cardiomyocytes in both normal and genetically modified mice. Both the normal and genetically modified mice are observed after aerobic exercise and their heart rates are recorded and compared. After a 10-minute session on a treadmill, the average pulse measured in the normal mice is 680/min, whereas in the genetically modified mice it is only 160/min. Which of the following is most likely to account for the increased heart rate seen in the normal mice?", "answer": "Greater T-tubule density", "options": {"A": "Greater cardiomyocyte size", "B": "Lower threshold potential for Ca2+ channel opening", "C": "Greater ratio of heart to body weight", "D": "Lower number of gap junctions", "E": "Greater T-tubule density"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 54-year-old man presents to his primary care physician with a 2-month-history of diarrhea. He says that he feels the urge to defecate 3-4 times per day and that his stools have changed in character since the diarrhea began. Specifically, they now float, stick to the side of the toilet bowl, and smell extremely foul. His past medical history is significant for several episodes of acute pancreatitis secondary to excessive alcohol consumption. His symptoms are found to be due to a deficiency in an enzyme that is resistant to bile salts. Which of the following enzymes is most likely deficient in this patient?", "answer": "Colipase", "options": {"A": "Amylase", "B": "Chymotrypsin", "C": "Colipase", "D": "Enterokinase", "E": "Lipase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old woman comes to the physician because of worsening pain and swelling of her left knee. For the past year, she has had pain in her knees and hands bilaterally, but never this severe. During this period, she has also had difficulties moving around for about an hour in the mornings and has been sweating more than usual, especially at night. She has been sexually active with a new partner for the past 4 weeks, and they use condoms inconsistently. She occasionally drinks alcohol. The day before she drank 6 beers because she was celebrating a friend's birthday. Her temperature is 38.5°C (101.3°F), blood pressure is 110/70 mm Hg, and pulse is 92/min. The left knee is erythematous, swollen, and tender; movement is restricted due to pain. There is swelling of the metacarpophalangeal joints and proximal interphalangeal joints bilaterally. Arthrocentesis of the knee with synovial fluid analysis shows a greenish, turbid fluid, a cell count of 68,000 WBC/μL and Gram-negative diplococci. An x-ray of the affected knee is most likely to show which of the following findings?", "answer": "Joint space narrowing and bone erosions", "options": {"A": "Calcifications and osteolysis with moth-eaten appearance", "B": "Osteophytes and subchondral cysts", "C": "Irregularity or fragmentation of the tubercle", "D": "Calcification of the meniscal and hyaline cartilage", "E": "Joint space narrowing and bone erosions"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 35-year-old woman, gravida 2, para 1, at 16 weeks' gestation comes to the office for a prenatal visit. She reports increased urinary frequency but otherwise feels well. Pregnancy and delivery of her first child were uncomplicated. Her vital signs are within normal limits. Pelvic examination shows a uterus consistent in size with a 16-week gestation. Urinalysis shows mild glucosuria. Laboratory studies show a non-fasting serum glucose concentration of 110 mg/dL. Which of the following is the most likely explanation for this patient's glucosuria?", "answer": "Increased glomerular filtration rate", "options": {"A": "Decreased insulin production", "B": "Decreased SGLT2 expression", "C": "Increased glomerular filtration barrier permeability", "D": "Decreased insulin sensitivity", "E": "Increased glomerular filtration rate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 10-month-old boy is referred to the hospital because of suspected severe pneumonia. During the first month of his life, he had developed upper airway infections, bronchitis, and diarrhea. He has received all the immunizations according to his age. He failed to thrive since the age of 3 months. A month ago, he had a severe lung infection with cough, dyspnea, and diarrhea, and was unresponsive to an empiric oral macrolide. Upon admission to his local hospital, the patient has mild respiratory distress and crackles on auscultation. The temperature is 39.5°C (103.1°F), and the oxygen saturation is 95% on room air. The quantitative immunoglobulin tests show increased IgG, IgM, and IgA. The peripheral blood smear shows leukocytosis and normochromic normocytic anemia. The chloride sweat test and tuberculin test are negative. The chest X-ray reveals bilateral pneumonia. The bronchoalveolar lavage and gram stain report gram-negative bacteria with a growth of Burkholderia cepacia on culture. The laboratory results on admission are as follows:\nLeukocytes 36,600/mm3\nNeutrophils 80%\nLymphocytes 16%\n  Eosinophils 1%\nMonocytes 2%\nHemoglobin 7.6 g/dL\nCreatinine 0.8 mg/dL\nBUN 15 mg/dL\nWhich of the following defects of neutrophil function is most likely responsible?", "answer": "Absent respiratory burst", "options": {"A": "Absent respiratory burst", "B": "Leukocyte adhesion molecule deficiency", "C": "X-linked agammaglobulinemia", "D": "Phagocytosis defect", "E": "Lysosomal trafficking defect"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 74-year-old man presents to the physician with a painful lesion over his right lower limb which began 2 days ago. He says that the lesion began with pain and severe tenderness in the area. The next day, the size of the lesion increased and it became erythematous. He also mentions that a similar lesion had appeared over his left lower limb 3 weeks earlier, but it disappeared after a few days of taking over the counter analgesics. There is no history of trauma, and the man does not have any known medical conditions. On physical examination, the physician notes a cordlike tender area with erythema and edema. There are no signs suggestive of deep vein thrombosis or varicose veins. Which of the following malignancies is most commonly associated with the lesion described in the patient?", "answer": "Adenocarcinoma of pancreas", "options": {"A": "Basal cell carcinoma", "B": "Multiple myeloma", "C": "Malignant melanoma", "D": "Squamous cell carcinoma of head and neck", "E": "Adenocarcinoma of pancreas"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 53-year-old man is being evaluated for a 3-week history of fatigue, difficulty to concentrate, dyspnea with exertion, dizziness, and digital pain that improves with cold. He has smoked half a pack of cigarettes a day since he was 20. His current medical history involves hypertension. He takes enalapril daily. The vital signs include a blood pressure of 131/82 mm Hg, a heart rate of 95/min, and a temperature of 36.9°C (98.4°F). On physical examination, splenomegaly is found. A complete blood count reveals thrombocytosis of 700,000 cells/m3. Lab work further shows decreased serum iron, iron saturation, and serum ferritin and increased total iron binding capacity. A blood smear reveals an increased number of abnormal platelets, and a bone marrow aspirate confirmed the presence of dysplastic megakaryocytes. A mutation on his chromosome 9 confirms the physician’s suspicion of a certain clonal myeloproliferative disease. The patient is started on hydroxyurea. What is the most likely diagnosis?", "answer": "Essential thrombocythemia", "options": {"A": "Myelofibrosis with myeloid metaplasia", "B": "Essential thrombocythemia", "C": "Chronic myelogenous leukemia", "D": "Polycythemia vera", "E": "Aplastic anemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 50-year-old Caucasian man presents for a routine checkup. He does not have any current complaint. He is healthy and takes no medications. He has smoked 10–15 cigarettes per day for the past 10 years. His family history is negative for gastrointestinal disorders. Which of the following screening tests is recommended for this patient according to the United States Preventive Services Task Force (USPSTF)?", "answer": "Colonoscopy for colorectal cancer", "options": {"A": "Prostate-specific antigen for prostate cancer", "B": "Carcinoembryonic antigen for colorectal cancer ", "C": "Abdominal ultrasonography for abdominal aortic aneurysm", "D": "Low-dose computerized tomography for lung cancer", "E": "Colonoscopy for colorectal cancer"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 76-year-old man comes to the physician for a follow-up examination. One week ago, he was prescribed azithromycin for acute bacterial sinusitis. He has a history of atrial fibrillation treated with warfarin and metoprolol. Physical examination shows no abnormalities. Compared to one month ago, laboratory studies show a mild increase in INR. Which of the following best explains this patient's laboratory finding?", "answer": "Depletion of intestinal flora", "options": {"A": "Depletion of intestinal flora", "B": "Inhibition of cytochrome p450", "C": "Increased non-protein bound warfarin fraction", "D": "Drug-induced hepatotoxicity", "E": "Increased gastrointestinal absorption of warfarin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-week-old male newborn is brought to the physician because his mother has noticed her son has occasional bouts of \"\"turning blue in the face\"\" while crying. He also tires easily and sweats while feeding. He weighed 2150 g (4 lb 11 oz) at birth and has gained 200 g (7 oz). The baby appears mildly cyanotic. Examination shows a 3/6 systolic ejection murmur heard over the left upper sternal border. A single S2 is present. An echocardiography confirms the diagnosis. Which of the following factors is the main determinant of the severity of this patient's cyanosis?\"", "answer": "Right ventricular outflow obstruction", "options": {"A": "Right ventricular outflow obstruction", "B": "Left ventricular outflow obstruction", "C": "Right ventricular hypertrophy", "D": "Ventricular septal defect", "E": "Atrial septal defect"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 19-year-old man presents to an orthopedic surgeon to discuss repair of his torn anterior cruciate ligament. He suffered the injury during a college basketball game 1 week ago and has been using a knee immobilizer since the accident. His past medical history is significant for an emergency appendectomy when he was 12 years of age. At that time, he said that he never wanted to have surgery again. At this visit, the physician explains the procedure to him in detail including potential risks and complications. The patient acknowledges and communicates his understanding of both the diagnosis as well as the surgery and decides to proceed with the surgery in 3 weeks. Afterward, he signs a form giving consent for the operation. Which of the following statements is true about this patient?", "answer": "He has the right to revoke his consent at any time", "options": {"A": "He cannot provide consent because he lacks capacity", "B": "He did not need to provide consent for this procedure since it is obviously beneficial", "C": "He has the right to revoke his consent at any time", "D": "His consent is invalid because his decision is not stable over time", "E": "His parents also need to give consent to this operation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old male presents with complaints of intermittent facial flushing. He also reports feeling itchy after showering. On review of systems, the patient says he has been having new onset headaches recently. On physical exam, his vital signs, including O2 saturation, are normal. He has an abnormal abdominal mass palpable in the left upper quadrant. A complete blood count reveals: WBCs 6500/microliter; Hgb 18.2 g/dL; Platelets 385,000/microliter. Which of the following is most likely responsible for his presentation?", "answer": "Tyrosine kinase mutation", "options": {"A": "Elevated serum erythropoietin levels", "B": "Fibrosis of bone marrow", "C": "Tyrosine kinase mutation", "D": "BCR-ABL fusion", "E": "Chronic hypoxemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old Caucasian male presents to your office with hematuria and right flank pain. He has no history of renal dialysis but has a history of recurrent urinary tract infections. You order an intravenous pyelogram, which reveals multiple cysts of the collecting ducts in the medulla. What is the most likely diagnosis?", "answer": "Medullary sponge kidney", "options": {"A": "Simple retention cysts", "B": "Acquired polycystic kidney disease", "C": "Autosomal dominant polycystic kidney disease", "D": "Medullary sponge kidney", "E": "Chronic renal failure"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old woman presents with severe vertigo. She also reports multiple episodes of vomiting and difficulty walking. The vertigo is continuous, not related to the position, and not associated with tinnitus or hearing disturbances. She has a past history of acute vision loss in her right eye that resolved spontaneously several years ago. She also experienced left-sided body numbness 3 years ago that also resolved rapidly. She only recently purchased health insurance and could not fully evaluate the cause of her previous symptoms at the time they presented. The patient is afebrile and her vital signs are within normal limits. On physical examination, she is alert and oriented. An ophthalmic exam reveals horizontal strabismus. There is no facial asymmetry and her tongue is central on the protrusion. Gag and cough reflexes are intact. Muscle strength is 5/5 bilaterally. She has difficulty maintaining her balance while walking and is unable to perform repetitive alternating movements with her hands. Which of the following is the best course of treatment for this patient’s condition?", "answer": "High-doses of corticosteroids", "options": {"A": "Acyclovir", "B": "Azathioprine", "C": "High doses of glucose", "D": "High-doses of corticosteroids", "E": "Plasma exchange"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 19-year-old man is brought to the emergency department by the resident assistant of his dormitory for strange behavior. He was found locked out of his room, where the patient admitted to attending a fraternity party before becoming paranoid that the resident assistant would report him to the police. The patient appears anxious. His pulse is 105/min, and blood pressure is 142/85 mm Hg. Examination shows dry mucous membranes and bilateral conjunctival injection. Further evaluation is most likely to show which of the following?", "answer": "Impaired reaction time", "options": {"A": "Tactile hallucinations", "B": "Pupillary constriction", "C": "Synesthesia", "D": "Sense of closeness to others", "E": "Impaired reaction time"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old primigravid woman comes to the physician at 36 weeks' gestation for her first prenatal visit. She confirmed the pregnancy with a home urine pregnancy kit a few months ago but has not yet followed up with a physician. She takes no medications. Vital signs are within normal limits. Pelvic examination shows a uterus consistent in size with a 36-week gestation. Laboratory studies show:\nHemoglobin 10.6 g/dL\nSerum\nGlucose 88 mg/dL\nHepatitis B surface antigen negative\nHepatitis C antibody negative\nHIV antibody positive\nHIV load 11,000 copies/mL (N < 1000 copies/mL)\nUltrasonography shows an intrauterine fetus consistent in size with a 36-week gestation. Which of the following is the most appropriate next step in management of this patient?\"", "answer": "Start cART and schedule cesarean delivery at 38 weeks' gestation", "options": {"A": "Intrapartum zidovudine and vaginal delivery when labor occurs", "B": "Start cART and schedule cesarean delivery at 38 weeks' gestation", "C": "Start cART and prepare for vaginal delivery at 38 weeks' gestation", "D": "Intrapartum zidovudine and cesarean delivery at 38 weeks' gestation", "E": "Conduct cesarean delivery immediately"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 54-year-old woman comes to the emergency department because of drooping on the left side of her face since that morning. She also reports difficulty closing her eyes and chewing. During the neurologic examination, the physician asks the patient to open her jaw against resistance. Which of the following muscles is most likely activated in this movement?", "answer": "Lateral pterygoid", "options": {"A": "Lateral pterygoid", "B": "Masseter", "C": "Orbicularis oris", "D": "Hyoglossus", "E": "Buccinator"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old female with a history of gastroesophageal reflux disease presents to her family physician with symptoms of epigastric pain right after a meal. The physician performs a urea breath test which is positive and the patient is started on appropriate medical therapy. Three days later at a restaurant, she experienced severe flushing, tachycardia, hypotension, and vomiting after her first glass of wine. Which of the following is the mechanism of action of the medication causing this side effect?", "answer": "Forms toxic metabolites that damage bacterial DNA", "options": {"A": "Blocks the synthesis of the peptidoglycan layer", "B": "Blocks protein synthesis by binding to the 50S ribosomal subunit inhibiting protein translocation", "C": "Binds to the 30S ribosomal subunit preventing attachment of the aminoacyl-tRNA", "D": "Forms toxic metabolites that damage bacterial DNA", "E": "Inhibits the H+/K+ ATPase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 53-year-old woman presents to your office with several months of fatigue and abdominal pain. The pain is dull in character and unrelated to meals. She has a history of type 2 diabetes mellitus and rheumatic arthritis for which she is taking ibuprofen, methotrexate, and metformin. She has 2-3 drinks on the weekends and does not use tobacco products. On physical examination, there is mild tenderness to palpation in the right upper quadrant. The liver span is 15 cm at the midclavicular line. Laboratory results are as follows:\n\nSerum:\nNa+: 135 mEq/L\nCl-: 100 mEq/L\nK+: 3.7 mEq/L\nHCO3-: 24 mEq/L\nBUN: 13 mg/dL\nCreatinine: 1.0 mg/dL\nAlkaline phosphatase: 100 U/L\nAST: 70 U/L\nALT: 120 U/L\nBilirubin (total): 0.5 mg/dL\nBilirubin (conjugated): 0.1 mg/dL\nAmylase: 76 U/L\n\nWhat is the most likely cause of her clinical presentation?", "answer": "Fatty infiltration of hepatocytes", "options": {"A": "Copper accumulation in hepatocytes", "B": "Fatty infiltration of hepatocytes", "C": "Autoimmune destruction of the intralobular bile ducts", "D": "Alcohol-induced destruction of hepatocytes", "E": "Drug-induced liver damage"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old man presents with low-grade fever and shortness of breath for the last 3 weeks. Past medical history is significant for severe mitral regurgitation status post mitral valve replacement five years ago. His temperature is 38.3°C (101.0°F) and respiratory rate is 18/min. Physical examination reveals vertical hemorrhages under his nails, multiple painless erythematous lesions on his palms, and two tender, raised nodules on his fingers. Cardiac auscultation reveals a new-onset 2/6 holosystolic murmur loudest at the apex with the patient in the left lateral decubitus position. A transesophageal echocardiogram reveals vegetations on the prosthetic valve. Blood cultures reveal catalase-positive, gram-positive cocci. Which of the following characteristics is associated with the organism most likely responsible for this patient’s condition?", "answer": "Novobiocin sensitive", "options": {"A": "Hemolysis", "B": "Optochin sensitive", "C": "Coagulase positive", "D": "DNAse positive", "E": "Novobiocin sensitive"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old woman with asthma is brought to the emergency department because of shortness of breath and wheezing for 20 minutes. She is unable to speak more than a few words at a time. Her pulse is 116/min and respirations are 28/min. Pulse oximetry on room air shows an oxygen saturation of 92%. Examination of the lungs shows decreased breath sounds and scattered end-expiratory wheezing over all lung fields. Treatment with high-dose continuous inhaled albuterol is begun. This patient is at increased risk for which of the following adverse effects?", "answer": "Hypokalemia", "options": {"A": "Miosis", "B": "Hypoglycemia", "C": "Hypokalemia", "D": "Sedation", "E": "Urinary frequency"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 59-year-old man comes to the physician because of a 4-month history of a pruritic rash. His symptoms have not improved despite treatment with over-the-counter creams. During this period, he has also had a 6-kg (13.5-lb) weight loss. Examination shows a scaly rash over his chest, back, and thighs. A photograph of the rash on his thighs is shown. A biopsy of the skin lesions shows clusters of neoplastic cells with cerebriform nuclei within the epidermis. This patient's condition is most likely caused by the abnormal proliferation of which of the following cell types?", "answer": "T cells", "options": {"A": "T cells", "B": "Keratinocytes", "C": "Mast cells", "D": "Melanocytes", "E": "B cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought in by his mother to his pediatrician for headache and nausea. His headaches began approximately 3 weeks ago and occur in the morning. Throughout the 3 weeks, his nausea has progressively worsened, and he had 2 episodes of emesis 1 day ago. On physical exam, cranial nerves are grossly intact, and his visual field is intact. The patient has a broad-based gait and difficulty with heel-to-toe walking, as well as head titubation. Fundoscopy demonstrates papilledema. A T1 and T2 MRI of the brain is demonstrated in Figures A and B, respectively. Which of the following is most likely the diagnosis?", "answer": "Medulloblastoma", "options": {"A": "Craniopharyngioma", "B": "Ependymoma", "C": "Medulloblastoma", "D": "Pilocytic astrocytoma", "E": "Pinealoma"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A simple experiment is performed to measure the breakdown of sucrose into glucose and fructose by a gut enzyme that catalyzes this reaction. A glucose meter is used to follow the breakdown of sucrose into glucose. When no enzyme is added to the sucrose solution, the glucose meter will have a reading of 0 mg/dL; but when the enzyme is added, the glucose meter will start to show readings indicative of glucose being formed. Which of the following diabetic pharmacological agents, when added before the addition of the gut enzyme to the sucrose solution, will maintain a reading of 0 mg/dL?", "answer": "Acarbose", "options": {"A": "Insulin", "B": "Glyburide", "C": "Metformin", "D": "Acarbose", "E": "Exenatide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Three days into hospitalization for a fractured distal femur, a 33-year-old man develops dyspnea and confusion. He has no history of a serious illness. He is unable to answer any questions or follow any commands. His blood pressure is 145/90 mm Hg, the pulse is 120/min, the respiratory rate is 36/min, and the temperature is 36.7°C (98.1°F). His oxygen saturation is 90% on 80% FiO2. On examination, purpura is noted on the anterior chest, head, and neck. Inspiratory crackles are heard in both lung fields. Arterial blood gas analysis on 80% FiO2 shows:\npH 7.54\nPCO2 17 mm Hg\nPO2 60 mm Hg\nHCO3− 22 mEq/L\nA chest X-ray is shown. Which of the following best explains the cause of these findings?", "answer": "Fat embolism", "options": {"A": "Acute respiratory distress syndrome", "B": "Fat embolism", "C": "Hospital-acquired pneumonia", "D": "Pulmonary contusion", "E": "Pulmonary thromboembolism"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman comes to the emergency department for a 2-week history of right upper quadrant abdominal pain. She has also been feeling tired and nauseous for the past 5 weeks. She has a history of depression and suicidal ideation. She is a social worker for an international charity foundation. She used intravenous illicit drugs in the past but quit 4 months ago. Her only medication is sertraline. Her temperature is 37.8°C (100.0°F), pulse is 100/min, and blood pressure is 128/76 mm Hg. She is alert and oriented. Scleral icterus is present. Abdominal examination shows tenderness to palpation in the right upper quadrant. The liver edge is palpated 3 cm below the right costal margin. There is no rebound tenderness or guarding. The abdomen is non-distended and the fluid wave test is negative. She is able to extend her arms with wrists in full extension and hold them steady without flapping. Laboratory studies show:\nHemoglobin 13.8 g/dL\nLeukocytes 13,700/mm3\nPlatelets 165,000/mm3\nProthrombin time 14 seconds\nPartial thromboplastin time 35 seconds\nSerum:\nTotal bilirubin 4.8 mg/dL\nDirect bilirubin 1.3 mg/dL\nAspartate aminotransferase 1852 U/L\nAlanine aminotransferase 2497 U/L\nUrea nitrogen 21 mg/dL\nCreatinine 1.2 mg/dL\nHepatitis A IgM antibody Negative\nHepatitis B surface antigen Negative\nHepatitis B surface antibody Negative\nHepatitis B core IgM antibody Positive\nHepatitis C antibody Positive\nHepatitis C RNA Negative\nUrine beta-hCG Negative\nWhich of the following is the most appropriate next step in management?\"", "answer": "Supportive therapy", "options": {"A": "Pegylated interferon-alpha", "B": "Supportive therapy", "C": "Tenofovir", "D": "Ribavirin and interferon", "E": "Vaccination against Hepatitis B"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man comes to the physician because of sudden-onset fever, malaise, and pain and swelling of his wrists and ankles that began a week ago. One month ago, he was started on hydralazine for adjunctive treatment of hypertension. His temperature is 37.8°C (100°F). Examination shows swelling, tenderness, warmth, and erythema of both wrists and ankles; range of motion is limited. Further evaluation is most likely to show an increased level of which of the following autoantibodies?", "answer": "Anti-histone", "options": {"A": "Anti-dsDNA", "B": "Anti-Smith", "C": "Anti-β2-glycoprotein", "D": "Anti-histone", "E": "Anti-Jo-1"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old man who recently immigrated to the United States from Haiti comes to the physician because of a 3-week history of progressively worsening exertional dyspnea and fatigue. For the past few days, he has also had difficulty lying flat due to trouble breathing. Over the past year, he has had intermittent fever, night sweats, and cough but he has not been seen by a physician for evaluation of these symptoms. His temperature is 37.8°C (100°F). An x-ray of the chest is shown. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Jugular venous distention on inspiration", "options": {"A": "Elimination of S2 heart sound splitting with inspiration", "B": "Head bobbing in synchrony with heart beat", "C": "\"Prominent \"\"a\"\" wave on jugular venous pressure tracing\"", "D": "Jugular venous distention on inspiration", "E": "Crescendo-decrescendo systolic ejection murmur"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man with a past medical history of obesity and hyperlipidemia suddenly develops left-sided chest pain and shortness of breath while at work. He relays to coworkers that the pain is intense and has spread to his upper left arm over the past 10 minutes. He reports it feels a lot like the “heart attack” he had a year ago. He suddenly collapses and is unresponsive. Coworkers perform cardiopulmonary resuscitation for 18 minutes until emergency medical services arrives. Paramedics pronounce him dead at the scene. Which of the following is the most likely cause of death in this man?", "answer": "Ventricular tachycardia", "options": {"A": "Aortic dissection", "B": "Atrial fibrillation", "C": "Free wall rupture", "D": "Pericarditis", "E": "Ventricular tachycardia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 13-year-old girl is brought to the physician for evaluation of a 2-month history of fatigue. She reports recurrent episodes of pain in her right wrist and left knee. During this period, she has had a 4-kg (8.8-lb) weight loss. Her mother has rheumatoid arthritis. Her temperature is 38°C (100.4°F). Examination shows diffuse lymphadenopathy. Oral examination shows several painless oral ulcers. The right wrist and the left knee are swollen and tender. Laboratory studies show a hemoglobin concentration of 9.8 g/dL, a leukocyte count of 2,000/mm3, and a platelet count of 75,000/mm3. Urinalysis shows excessive protein. This patient's condition is associated with which of the following laboratory findings?", "answer": "Anti-dsDNA antibodies", "options": {"A": "Leukocytoclastic vasculitis with IgA and C3 immune complex deposition", "B": "Anti-dsDNA antibodies", "C": "Anti-citrullinated peptide antibodies", "D": "Excessive lymphoblasts", "E": "Positive HLA-B27 test"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old man comes to the emergency department because of palpitations, dizziness, and substernal chest pain for three hours. The day prior, he was at a friend’s wedding, where he consumed seven glasses of wine. The patient appears diaphoretic. His pulse is 220/min and blood pressure is 120/84 mm Hg. Based on the patient's findings on electrocardiography, the physician diagnoses atrial fibrillation with rapid ventricular response and administers verapamil for rate control. Ten minutes later, the patient is unresponsive and loses consciousness. Despite resuscitative efforts, the patient dies. Histopathologic examination of the heart at autopsy shows an accessory atrioventricular conduction pathway. Electrocardiography prior to the onset of this patient's symptoms would most likely have shown which of the following findings?", "answer": "Slurred upstroke of the QRS complex", "options": {"A": "Slurred upstroke of the QRS complex", "B": "Cyclic alteration of the QRS axis", "C": "Epsilon wave following the QRS complex", "D": "Prolongation of the QT interval", "E": "Positive Sokolow-Lyon index"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A typically healthy 27-year-old woman presents to the physician because of a 3-week history of fatigue, headache, and dry cough. She does not smoke or use illicit drugs. Her temperature is 37.8°C (100.0°F). Chest examination shows mild inspiratory crackles in both lung fields. An X-ray of the chest shows diffuse interstitial infiltrates bilaterally. A Gram stain of saline-induced sputum shows no organisms. Inoculation of the induced sputum on a cell-free medium that is enriched with yeast extract, horse serum, cholesterol, and penicillin G grows colonies that resemble fried eggs. Which of the following is the most appropriate next step in management?", "answer": "Oral azithromycin", "options": {"A": "Intravenous ceftriaxone", "B": "Intravenous ceftriaxone and oral azithromycin", "C": "Intravenous clindamycin", "D": "Oral amoxicillin", "E": "Oral azithromycin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 59-year-old Caucasian man with a history of hypertension and emphysema is brought to the hospital because of progressive lethargy and confusion. The patient has been experiencing poor appetite for the past 3 months and has unintentionally lost 9 kg (19.8 lb). He was a smoker for 35 years and smoked 1 pack daily, but he quit 5 years ago. He takes lisinopril and bisoprolol for hypertension and has no allergies. On examination, the patient appears cachectic. He responds to stimulation but is lethargic and unable to provide any significant history. His blood pressure is 138/90 mm Hg, heart rate is 100/min, and his oxygen saturation on room air is 90%. His mucous membranes are moist, heart rate is regular without murmurs or an S3/S4 gallop, and his extremities are without any edema. His pulmonary examination shows mildly diminished breath sounds in the right lower lobe with bilateral wheezing. His laboratory values are shown:\nSodium 110 mEq/L\nPotassium 4.1 mEq/L\nChloride 102 mEq/L\nCO2 41 mm Hg\nBUN 18\nCreatinine 1.3 mg/dL\nGlucose 93 mg/dL\nUrine osmolality 600 mOsm/kg H2O\nPlasma osmolality 229 mEq/L\nWBC 8,200 cells/mL\nHgb 15.5 g/dL\nArterial blood gas pH 7.36/pCO2 60/pO2 285\nChest X-ray demonstrates a mass in the right upper lobe. What is the most appropriate treatment to address the patient’s hyponatremia?", "answer": "3% saline at 35 mL/h", "options": {"A": "Dextrose with 20 mEq/L KCl at 250 mL/h", "B": "0.9% saline at 125 mL/h", "C": "0.45% saline at 100 mL/h", "D": "3% saline at 35 mL/h", "E": "0.45% saline with 30 mEq/L KCl at 100 mL/h"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old male presents with a testicular mass of unknown duration. The patient states he first noticed something unusual with his right testicle two weeks ago, but states he did not think it was urgent because it was not painful and believed it would resolve on its own. It has not changed since he first noticed the mass, and the patient still denies pain. On exam, the patient’s right testicle is non-tender, and a firm mass is felt. There is a negative transillumination test, and the mass is non-reducible. Which of the following is the best next step in management?", "answer": "Testicular ultrasound", "options": {"A": "Needle biopsy", "B": "Testicular ultrasound", "C": "MRI abdomen and pelvis", "D": "CT abdomen and pelvis", "E": "Send labs"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 1-year-old boy is brought to the emergency department after his mother witnessed him swallow a nickel-sized battery a few hours ago. She denies any episodes of vomiting or hematemesis. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 95/45 mm Hg, pulse 140/min, respiratory rate 15/min, and oxygen saturation 99% on room air. On physical examination, the patient is alert and responsive. The oropharynx is clear. The cardiac exam is significant for a grade 2/6 holosystolic murmur loudest at the left lower sternal border. The lungs are clear to auscultation. The abdomen is soft and nontender with no hepatosplenomegaly. Bowel sounds are present. What is the most appropriate next step in the management of this patient?", "answer": "Immediate endoscopic removal", "options": {"A": "Induce emesis to expel the battery", "B": "Induce gastrointestinal motility with metoclopramide to expel the battery", "C": "Reassurance and observation for the next 24 hours", "D": "Computed tomography (CT) scan to confirm the diagnosis ", "E": "Immediate endoscopic removal"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 28-year-old soldier is brought back to a military treatment facility 45 minutes after sustaining injuries in a building fire from a mortar attack. He was trapped inside the building for around 20 minutes. On arrival, he is confused and appears uncomfortable. He has a Glasgow Coma Score of 13. His pulse is 113/min, respirations are 18/min, and blood pressure is 108/70 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Examination shows multiple second-degree burns over the chest and bilateral upper extremities and third-degree burns over the face. There are black sediments seen within the nose and mouth. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft and nontender. Intravenous fluid resuscitation is begun. Which of the following is the most appropriate next step in management?", "answer": "Intubation and mechanical ventilation", "options": {"A": "Insertion of nasogastric tube and enteral nutrition", "B": "Intravenous antibiotic therapy", "C": "Intubation and mechanical ventilation", "D": "Intravenous corticosteroid therapy", "E": "Immediate bronchoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 49-year-old woman presents to her primary care physician for a routine health maintenance examination. She says that she is currently feeling well and has not noticed any acute changes in her health. She exercises 3 times a week and has tried to increase the amount of fruits and vegetables in her diet. She has smoked approximately 1 pack of cigarettes every 2 days for the last 20 years. Her last pap smear was performed 2 years ago, which was unremarkable. Her past medical history includes hypertension and type II diabetes. Her mother was diagnosed with breast cancer at 62 years of age. The patient is 5 ft 5 in (165.1 cm), weighs 185 lbs (84 kg), and has a BMI of 30.8 kg/m^2. Her blood pressure is 155/98 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination is unremarkable. Lipid studies demonstrate an LDL cholesterol of 130 mg/dL and an HDL cholesterol of 42 mg/dL. Which of the following is the best next step in management?", "answer": "Statin therapy", "options": {"A": "Chest radiography", "B": "Colonoscopy", "C": "Mammogram", "D": "Pap smear", "E": "Statin therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old woman with a past medical history of anorexia nervosa presents to the clinic due to heavy menses, bleeding gums, and easy bruisability. She says she is trying to lose weight by restricting her food intake. She has taken multiple courses of antibiotics for recurrent sinusitis over the past month. No other past medical history or current medications. She is not sexually active. Her vital signs are as follows: temperature 37.0°C (98.6°F), blood pressure 90/60 mm Hg, heart rate 100/min, respiratory rate 16/min. Her BMI is 16 kg/m2. Her physical examination is significant for ecchymosis on the extremities, dry mucous membranes, and bleeding gums. A gynecological exam is non-contributory. Laboratory tests show a prolonged PT, normal PTT, and normal bleeding time. CBC shows microcytic anemia, normal platelets, and normal WBC. Her urine pregnancy test is negative. Which of the following is the most likely cause of her condition?", "answer": "Vitamin K deficiency", "options": {"A": "Vitamin K deficiency", "B": "Acute myelogenous leukemia", "C": "Missed miscarriage", "D": "Immune thrombocytopenic purpura", "E": "Physical abuse"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old obese female presents to the emergency room complaining of severe abdominal pain. She reports pain localized to the epigastrium that radiates to the right scapula. The pain occurred suddenly after a fast food meal with her grandchildren. Her temperature is 100.9°F (38.2°C), blood pressure is 140/85 mmHg, pulse is 108/min, and respirations are 20/min. On examination, she demonstrates tenderness to palpation in the epigastrium. She experiences inspiratory arrest during deep palpation of the right upper quadrant but this exam finding is not present on the left upper quadrant. A blockage at which of the following locations is most likely causing this patient’s symptoms?", "answer": "Cystic duct", "options": {"A": "Common hepatic duct", "B": "Ampulla of Vater", "C": "Cystic duct", "D": "Pancreatic duct of Wirsung", "E": "Common bile duct"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year-old Asian woman presents to her primary care physician with joint pain and a headache. She has had intermittent joint and muscle pain for the past several months in the setting of a chronic headache. She states that the pain seems to migrate from joint to joint, and her muscles typically ache making it hard for her to sleep. The patient's past medical history is non-contributory, and she is currently taking ibuprofen for joint pain. Physical exam is notable for an asymmetrical pulse in the upper extremities. The patient has lost 10 pounds since her previous visit 2 months ago. Laboratory values are notable for an elevated C-reactive protein and erythrocyte sedimentation rate. Which of the following is the best next step in management?", "answer": "Prednisone", "options": {"A": "Anti-dsDNA level", "B": "Methotrexate", "C": "Prednisone", "D": "Recommend exercise and optimize the patient's sleep regimen", "E": "Temporal artery biopsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Your colleague has been reading the literature on beta-carotene supplementation and the risk of heart disease. She thinks they may share a clinically relevant association and would like to submit an editorial to a top journal. Upon final literature review, she discovers a newly published study that refutes any association between beta-carotene and heart disease. Your colleague is upset; you suggest that she, instead, mathematically pool the results from all of the studies on this topic and publish the findings. What type of study design are you recommending to your colleague?", "answer": "Meta-analysis", "options": {"A": "Randomized control trial", "B": "Systematic review", "C": "Case-cohort study", "D": "Meta-analysis", "E": "Cross-sectional study"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-year-old girl comes to the physician with her father for evaluation of short stature. She feels well overall but is concerned because all of her friends are taller than her. Her birth weight was normal. Menarche has not yet occurred. Her father says he also had short stature and late puberty. The girl is at the 5th percentile for height and 35th percentile for weight. Breast development is Tanner stage 2. Pubic and axillary hair is absent. An x-ray of the left hand and wrist shows a bone age of 12 years. Further evaluation of this patient is most likely to show which of the following sets of laboratory findings?\n $$$ FSH %%% LH %%% Estrogen %%% GnRH $$$", "answer": "Normal normal normal normal", "options": {"A": "↓ ↓ ↓ ↓", "B": "↓ ↓ ↑ ↓", "C": "Normal normal normal normal", "D": "↑ ↑ ↓ ↑", "E": "Normal normal ↓ normal"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "In which of the following pathological states would the oxygen content of the trachea resemble the oxygen content in the affected alveoli?", "answer": "Pulmonary embolism", "options": {"A": "Emphysema", "B": "Pulmonary fibrosis", "C": "Pulmonary embolism", "D": "Foreign body obstruction distal to the trachea", "E": "Exercise"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 32-year-old man comes to the physician because of a 1-week history of upper back pain, dyspnea, and a sensation of pressure in his chest. He has had no shortness of breath, palpitations, fevers, or chills. He emigrated from Ecuador when he was 5 years old. He does not smoke or drink alcohol. He takes no medications. He is 194 cm (6 ft 4 in) tall and weighs 70.3 kg (155 lb); BMI is 19 kg/m2. His temperature is 37.2°C (99.0°F), pulse is 73/min, respirations are 15/min, and blood pressure is 152/86 mm Hg in the right arm and 130/72 mg Hg in the left arm. Pulmonary examination shows faint inspiratory wheezing bilaterally. A CT scan of the chest with contrast is shown. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Cystic medial necrosis", "options": {"A": "Infection with Trypanosoma cruzi", "B": "Cystic medial necrosis", "C": "Large-vessel vasculitis", "D": "Atherosclerotic plaque formation", "E": "Congenital narrowing of the aortic arch"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old woman presents to the emergency department with fever, chills, lower quadrant abdominal pain, and urinary frequency for the past week. Her vital signs include temperature 38.9°C (102.0°F), pulse 110/min, respirations 16/min, and blood pressure 122/78 mm Hg. Physical examination is unremarkable. Urinalysis reveals polymorphonuclear leukocytes (PMNs) > 10 cells/HPF and the presence of bacteria (> 105 CFU/mL). Which of the following is correct concerning the most likely microorganism responsible for this patient’s condition?", "answer": "Gram-negative rod-shaped bacilli", "options": {"A": "Nonmotile, pleomorphic rod-shaped, gram-negative bacilli ", "B": "Pear-shaped motile protozoa", "C": "Gram-negative rod-shaped bacilli", "D": "Gram-positive cocci that grow in clusters", "E": "Gram-positive cocci that grow in chains"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old man comes to the emergency department because of the sudden onset of back pain beginning 2 hours ago. Beginning yesterday, he noticed that his eyes started appearing yellowish and his urine was darker than normal. Two months ago, he returned from a trip to Greece, where he lived before immigrating to the US 10 years ago. Three days ago, he was diagnosed with latent tuberculosis and started on isoniazid. He has worked as a plumber the last 5 years. His temperature is 37.4°C (99.3°F), pulse is 80/min, and blood pressure is 110/70 mm Hg. Examination shows back tenderness and scleral icterus. Laboratory studies show:\nHematocrit 29%\nLeukocyte count 8000/mm3\nPlatelet count 280,000/mm3\nSerum\nBilirubin\nTotal 4 mg/dL\nDirect 0.7 mg/dL\nHaptoglobin 15 mg/dL (N=41–165 mg/dL)\nLactate dehydrogenase 180 U/L\nUrine\nBlood 3+\nProtein 1+\nRBC 2–3/hpf\nWBC 2–3/hpf\nWhich of the following is the most likely underlying cause of this patient's anemia?\"", "answer": "Absence of reduced glutathione", "options": {"A": "Crescent-shaped erythrocytes", "B": "Absence of reduced glutathione", "C": "Inhibition of aminolevulinate dehydratase", "D": "Absence of uridine 5'-monophosphate", "E": "Defective ankyrin in the RBC membrane"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 69-year-old Caucasian man presents for a routine health maintenance examination. He feels well. He has no significant past medical history. He takes aspirin for the occasional headaches that he has had for over several years. He exercises every day and does not smoke. His father was diagnosed with a hematologic malignancy at 79 years old. The patient’s vital signs are within normal limits. Physical examination shows no abnormalities. The laboratory test results are as follows:\nHemoglobin 14.5 g/dL\nLeukocyte count 62,000/mm3\nPlatelet count 350,000/mm3\nA peripheral blood smear is obtained (shown on the image). Which of the following best explains these findings?", "answer": "Chronic lymphocytic leukemia", "options": {"A": "Acute lymphoid leukemia", "B": "Acute myeloid leukemia", "C": "Adult T cell leukemia", "D": "Chronic lymphocytic leukemia", "E": "Hairy cell leukemia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old woman is referred to a tertiary care hospital with a history of diplopia and fatigue for the past 3 months. She has also noticed difficulty in climbing the stairs and combing her hair. She confirms a history of 2.3 kg (5.0 lb) weight loss in the past 6 weeks and constipation. Past medical history is significant for type 2 diabetes mellitus. She has a 50-pack-year cigarette smoking history. Physical examination reveals a blood pressure of 135/78 mm Hg supine and 112/65 while standing, a heart rate of 82/min supine and 81/min while standing, and a temperature of 37.0°C (98.6°F). She is oriented to time and space. Her right upper eyelid is slightly drooped. She has difficulty in abducting the right eye. Pupils are bilaterally equal and reactive to light with accommodation. The corneal reflex is intact. Muscle strength is reduced in the proximal muscles of all 4 limbs, and the lower limbs are affected more when compared to the upper limbs. Deep tendon reflexes are bilaterally absent. After 10 minutes of cycling, the reflexes become positive. Sensory examination is normal. Diffuse wheezes are heard on chest auscultation. Which of the following findings is expected?", "answer": "Incremental pattern on repetitive nerve conduction studies", "options": {"A": "Antibodies against muscle-specific kinase", "B": "Elevated serum creatine kinase", "C": "Incremental pattern on repetitive nerve conduction studies", "D": "Periventricular plaques on MRI of the brain", "E": "Thymoma on CT scan of the chest"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 60-year-old man is brought to the emergency department by police officers because he was acting strangely in public. The patient was found talking nonsensically to characters on cereal boxes in the store. Past medical history is significant for multiple hospitalizations for alcohol-related injuries and seizures. The patient’s vital signs are within normal limits. Physical examination shows a disheveled male who is oriented to person, but not time or place. Neurologic examination shows nystagmus and severe gait ataxia. A T1/T2 MRI is performed and demonstrates evidence of damage to the mammillary bodies. The patient is given the appropriate treatment for recovering most of his cognitive functions. However, significant short-term memory deficits persist. The patient remembers events from his past such as the school and college he attended, his current job, and the names of family members quite well. Which of the following is the most likely diagnosis in this patient?", "answer": "Korsakoff's syndrome", "options": {"A": "Delirium", "B": "Delirium tremens", "C": "Korsakoff's syndrome", "D": "Schizophrenia", "E": "Wernicke encephalopathy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 43-year-old woman presents to her primary care physician for a general wellness appointment. The patient states that sometimes she has headaches and is ashamed of her body habitus. Otherwise, the patient has no complaints. The patient's 90-year-old mother recently died of breast cancer. The patient smokes 1 pack of cigarettes per day. She drinks 2-3 glasses of red wine per day with dinner. She has been considering having a child as she has just been promoted to a position that gives her more time off and a greater income. The patient's current medications include lisinopril, metformin, and a progesterone intrauterine device (IUD). On physical exam, you note a normal S1 and S2 heart sound. Pulmonary exam is clear to auscultation bilaterally. The patient's abdominal, musculoskeletal, and neurological exams are within normal limits. The patient is concerned about her risk for breast cancer and asks what she can do to reduce her chance of getting this disease. Which of the following is the best recommendation for this patient?", "answer": "Exercise and reduce alcohol intake", "options": {"A": "Switch to oral contraceptive pills for contraception", "B": "Begin breastfeeding", "C": "Test for BRCA1 and 2", "D": "Recommend monthly self breast exams", "E": "Exercise and reduce alcohol intake"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 12-year-old boy is brought to his pediatrician with a high fever. He was feeling fatigued yesterday and then developed a high fever overnight that was accompanied by chills and malaise. This morning he also started complaining of headaches and myalgias. He has otherwise been healthy and does not take any medications. He says that his friends came down with the same symptoms last week. He is given oseltamivir and given instructions to rest and stay hydrated. He is also told that this year the disease is particularly infectious and is currently causing a global pandemic. He asks the physician why the same virus can infect people who have already had the disease and is told about a particular property of this virus. Which of the following properties is required for the viral genetic change that permits global pandemics of this virus?", "answer": "Segmented genomic material", "options": {"A": "Concurrent infection with 2 viruses", "B": "Crossing over of homologous regions", "C": "Point mutations in the viral genetic code", "D": "One virus that produces a non-functional protein", "E": "Segmented genomic material"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old woman presents to the clinic with complaints of intermittent chest pain for 3 days. The pain is retrosternal, 3/10, and positional (laying down seems to make it worse). She describes it as “squeezing and burning” in quality, is worse after food intake and emotional stress, and improves with antacids. The patient recently traveled for 4 hours in a car. Past medical history is significant for osteoarthritis, hypertension and type 2 diabetes mellitus, both of which are moderately controlled. Medications include ibuprofen, lisinopril, and hydrochlorothiazide. She denies palpitations, dyspnea, shortness of breath, weight loss, fever, melena, or hematochezia. What is the most likely explanation for this patient’s symptoms?", "answer": "Incompetence of the lower esophageal sphincter", "options": {"A": "Blood clot within the lungs", "B": "Decreased gastric mucosal protection", "C": "Incompetence of the lower esophageal sphincter", "D": "Insufficient blood supply to the myocardium", "E": "Temporary blockage of the bile duct"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old man presents to the emergency department for severe abdominal pain for the past day. The patient states he has had profuse, watery diarrhea and abdominal pain that is keeping him up at night. The patient also claims that he sees blood on the toilet paper when he wipes and endorses having lost 5 pounds recently. The patient's past medical history is notable for IV drug abuse and a recent hospitalization for sepsis. His temperature is 99.5°F (37.5°C), blood pressure is 120/68 mmHg, pulse is 100/min, respirations are 14/min, and oxygen saturation is 98% on room air. On physical exam, you note a young man clutching his abdomen in pain. Abdominal exam demonstrates hyperactive bowel sounds and diffuse abdominal tenderness. Cardiopulmonary exam is within normal limits. Which of the following is the next best step in management?", "answer": "Vancomycin", "options": {"A": "Metronidazole", "B": "Vancomycin", "C": "Clindamycin", "D": "Mesalamine enema", "E": "Supportive therapy and ciprofloxacin if symptoms persist"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man is brought to the emergency department for worsening pain and swelling of his left ankle for the past 2 hours. The pain is severe and awakened him from sleep. He has hypertension and hyperlipidemia. Current medications include hydrochlorothiazide and pravastatin. His temperature is 37.8°C (100.1°F), pulse is 105/min, and blood pressure is 148/96 mm Hg. Examination shows exquisite tenderness, erythema, and edema of the left ankle; active and passive range of motion is limited by pain. Arthrocentesis of the ankle joint yields cloudy fluid with a leukocyte count of 19,500/mm3 (80% segmented neutrophils). Gram stain is negative. A photomicrograph of the joint fluid aspirate under polarized light is shown. Which of the following is the most appropriate pharmacotherapy?", "answer": "Colchicine", "options": {"A": "Probenecid", "B": "Colchicine and allopurinol", "C": "Triamcinolone and probenecid", "D": "Colchicine", "E": "Ketorolac and aspirin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old man presents to the physician because of dysphagia and regurgitation for the past 5 years. In recent weeks, it has become very difficult for him to ingest solid or liquid food. He has lost 3 kg (6 lb) during this time. He was admitted to the hospital last year because of pneumonia. Three years ago, he had an endoscopic procedure which partially improved his dysphagia. He takes amlodipine and nitroglycerine before meals. His vital signs are within normal limits. BMI is 19 kg/m2. Physical examination shows no abnormalities. A barium swallow X-ray is shown. Which of the following patterns of esophageal involvement is the most likely cause of this patient’s condition?", "answer": "Absent peristalsis and impaired lower esophageal sphincter relaxation", "options": {"A": "Abnormal esophageal contraction with deglutition lower esophageal sphincter relaxation", "B": "Absent peristalsis and impaired lower esophageal sphincter relaxation", "C": "Poor pharyngeal propulsion and upper esophageal sphincter obstruction", "D": "Sequenced inhibition followed by contraction of the musculature along the esophagus", "E": "Severely weak peristalsis and patulous lower esophageal sphincter"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 23-year-old woman is seen by her primary care physician. The patient has a several year history of excessive daytime sleepiness. She also reports episodes where she suddenly falls to the floor after her knees become weak, often during a laughing spell. She has no other significant past medical history. Her primary care physician refers her for a sleep study, which confirms the suspected diagnosis. Which of the following laboratory findings would also be expected in this patient?", "answer": "Undetectable CSF hypocretin-1", "options": {"A": "Increased serum methoxyhemoglobin", "B": "Reduced serum hemoglobin", "C": "Undetectable CSF hypocretin-1", "D": "Increased CSF oligoclonal bands", "E": "Increased serum ESR"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old woman comes to the physician with her husband because they have been trying to conceive for 15 months with no success. They have been sexually active at least twice a week. The husband sometimes has difficulties maintaining erection during sexual activity. During attempted vaginal penetration, the patient has discomfort and her pelvic floor muscles tighten up. Three years ago, the patient was diagnosed with body dysmorphic disorder. There is no family history of serious illness. She does not smoke or drink alcohol. She takes no medications. Vital signs are within normal limits. Pelvic examination shows normal appearing vulva without redness; there is no vaginal discharge. An initial attempt at speculum examination is aborted after the patient's pelvic floor muscles tense up and she experiences discomfort. Which of the following is the most likely diagnosis?", "answer": "Genitopelvic pain disorder", "options": {"A": "Vulvodynia", "B": "Vulvovaginitis", "C": "Painful bladder syndrome", "D": "Genitopelvic pain disorder", "E": "Endometriosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An otherwise healthy 76-year-old man is brought to the physician because of poor sleep for the past several years. Every night he has been sleeping less and taking longer to fall asleep. During the day, he feels tired and has low energy and difficulty concentrating. Sleep hygiene and relaxation techniques have failed to improve his sleep. He would like to start a short-term pharmacological therapy trial but does not want a drug that makes him drowsy during the day. Which of the following is the most appropriate pharmacotherapy for this patient?", "answer": "Zaleplon", "options": {"A": "Temazepam", "B": "Diphenhydramine", "C": "Suvorexant", "D": "Zaleplon", "E": "Flurazepam"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old man is brought to the emergency department by ambulance following a motor vehicle accident. He was pinned between 2 cars for several hours. The patient has a history of asthma. He uses an albuterol inhaler intermittently. The patient was not the driver, and admits to having a few beers at a party prior to the accident. His vitals in the ambulance are stable. Upon presentation to the emergency department, the patient is immediately brought to the operating room for evaluation and surgical intervention. It is determined that the patient’s right leg has a Gustilo IIIC injury in the mid-shaft of the tibia with a severely comminuted fracture. The patient’s left leg suffered a similar injury but with damage to the peroneal nerve. The anesthesiologist begins to induce anesthesia. Which of the following agents would be contraindicated in this patient?", "answer": "Succinylcholine", "options": {"A": "Etomidate", "B": "Halothane", "C": "Neostigmine", "D": "Propofol", "E": "Succinylcholine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-year-old girl is brought to the physician for a well-child visit. Her father is concerned about the color and strength of her teeth. He says that most of her teeth have had stains since the time that they erupted. She also has a limp when she walks. Examination shows brownish-gray discoloration of the teeth. She has lower limb length discrepancy; her left knee-to-ankle length is 4 cm shorter than the right. Which of the following drugs is most likely to have been taken by this child's mother when she was pregnant?", "answer": "Tetracycline", "options": {"A": "Trimethoprim", "B": "Ciprofloxacin", "C": "Gentamicin", "D": "Chloramphenicol", "E": "Tetracycline"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2300-g (5.07-lb) male newborn is delivered at term to a 39-year-old woman. Examination shows a sloping forehead, a flat nasal bridge, increased interocular distance, low-set ears, a protruding tongue, a single palmar crease and an increased gap between the first and second toe. There are small white and brown spots in the periphery of both irises. The abdomen is distended. An x-ray of the abdomen shows two large air-filled spaces in the upper quadrant. This patient's condition is most likely associated with which of the following cardiac anomalies?", "answer": "Atrioventricular septal defect", "options": {"A": "Patent ductus arteriosus", "B": "Atrial septal defects", "C": "Atrioventricular septal defect", "D": "Tetralogy of Fallot", "E": "Ventricular septal defect"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old woman comes to the physician because of a 3-week history of generalized fatigue, mild fever, abdominal pain, and nausea. She attended the state fair over a month ago, where she tried a number of regional foods, and wonders if it might have been caused by something she ate. She has also noticed darkening of her urine, which she attributes to not drinking enough water recently. She has type 2 diabetes mellitus. She drinks 1–2 beers daily. She works as nursing assistant in a rehabilitation facility. Current medications include glyburide, sitagliptin, and a multivitamin. She appears tired. Her temperature is 38.1°C (100.6°F), pulse is 99/min, and blood pressure is 110/74 mm Hg. Examination shows mild scleral icterus. The liver is palpated 2–3 cm below the right costal margin and is tender. Laboratory studies show:\nHemoglobin 10.6 g/dL\nLeukocyte count 11600/mm3\nPlatelet count 221,000/mm3\nSerum\nUrea nitrogen 26 mg/dL\nGlucose 122 mg/dL\nCreatinine 1.3 mg/dL\nBilirubin 3.6 mg/dL\nTotal 3.6 mg/dL\nDirect 2.4 mg/dL\nAlkaline phosphatase 72 U/L\nAST 488 U/L\nALT 798 U/L\nHepatitis A IgG antibody (HAV-IgG) positive\nHepatitis B surface antigen (HBsAg) positive\nHepatitis B core IgG antibody (anti-HBc) positive\nHepatitis B envelope antigen (HBeAg) positive\nHepatitis C antibody (anti-HCV) negative\nWhich of the following is the most likely diagnosis?\"", "answer": "Active chronic hepatitis B infection", "options": {"A": "Inactive chronic hepatitis B infection", "B": "Acute hepatitis B infection", "C": "Active chronic hepatitis B infection", "D": "Resolved acute hepatitis B infection", "E": "Alcoholic hepatitis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to the emergency department for evaluation of a progressive rash that started 2 days ago. The rash began on the face and progressed to the trunk and extremities. Over the past week, he has had a runny nose, a cough, and red, crusty eyes. He immigrated with his family from Turkey 3 months ago. His father and his older brother have Behcet disease. Immunization records are unavailable. The patient appears irritable and cries during the examination. His temperature is 40.0°C (104°F). Examination shows general lymphadenopathy and dry mucous membranes. Skin turgor is decreased. There is a blanching, partially confluent erythematous maculopapular exanthema. Examination of the oral cavity shows two 5-mm aphthous ulcers at the base of the tongue. His hemoglobin concentration is 11.5 g/dL, leukocyte count is 6,000/mm3, and platelet count is 215,000/mm3. Serology confirms the diagnosis. Which of the following is the most appropriate next step in management?", "answer": "Vitamin A supplementation", "options": {"A": "Intravenous immunoglobulin (IVIG)", "B": "Oral acyclovir", "C": "Vitamin A supplementation", "D": "Reassurance and follow-up in 3 days", "E": "Oral penicillin V"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-year-old boy presents to the ER with progressive dysphagia over the course of 3 months and a new onset fever for the past 24 hours. The temperature in the ER was 39.5°C (103.1°F). There are white exudates present on enlarged tonsils (Grade 2). Routine blood work reveals a WBC count of 89,000/mm3, with the automatic differential yielding a high (> 90%) percentage of lymphocytes. A peripheral blood smear is ordered, demonstrating the findings in the accompanying image. The peripheral smear is submitted to pathology for review. After initial assessment, the following results are found on cytologic assessment of the cells:\nTdT: positive\nCALLA (CD 10): positive\nWhich of the following cell markers are most likely to be positive as well? ", "answer": "CD 19", "options": {"A": "CD 8", "B": "CD 2", "C": "CD 7", "D": "CD 19", "E": "CD 5"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 74-year-old man presents to the emergency department with sudden onset of abdominal pain that is most felt around the umbilicus. The pain began 16 hours ago and has no association with meals. He has not been vomiting, but he has had several episodes of bloody loose bowel movements. He was hospitalized 1 week ago for an acute myocardial infarction. He has had diabetes mellitus for 35 years and hypertension for 20 years. He has smoked 15–20 cigarettes per day for the past 40 years. His temperature is 36.9°C (98.4°F), blood pressure is 95/65 mm Hg, and pulse is 95/min. On physical examination, the patient is in severe pain, there is a mild periumbilical tenderness, and a bruit is heard over the epigastric area. Which of the following is the most likely diagnosis?", "answer": "Acute mesenteric ischemia", "options": {"A": "Chronic mesenteric ischemia", "B": "Colonic ischemia", "C": "Acute mesenteric ischemia", "D": "Peptic ulcer disease", "E": "Irritable bowel syndrome"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 33-year-old woman, gravida 2, para 1, at 26 weeks' gestation comes to the emergency department because of frequent contractions. The contractions are 40 seconds each, occurring every 2 minutes, and increasing in intensity. Her first child was delivered by lower segment transverse cesarean section because of a nonreassuring fetal heart rate. Her current medications include folic acid and a multivitamin. Her temperature is 36.9°C (98.4°F), heart rate is 88/min, and blood pressure is 126/76 mm Hg. Contractions are felt on the abdomen. There is clear fluid in the vulva and the introitus. The cervix is dilated to 5 cm, 70% effaced, and station of the head is -2. A fetal ultrasound shows polyhydramnios, a median cleft lip, and fused thalami. The corpus callosum, 3rd ventricle, and lateral ventricles are absent. The spine shows no abnormalities and there is a four chamber heart. Which of the following is the most appropriate next step in management?", "answer": "Allow vaginal delivery", "options": {"A": "Perform cesarean delivery", "B": "Allow vaginal delivery", "C": "Initiate misoprostol therapy", "D": "Perform dilation and evacuation", "E": "Initiate nifedipine therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old man comes to the physician for a 2-month history of an itchy rash on his forearm. He feels well otherwise and has not had any fever or chills. He returned from an archaeological expedition to Guatemala 4 months ago. Skin examination shows a solitary, round, pink-colored plaque with central ulceration on the right wrist. There is right axillary lymphadenopathy. A photomicrograph of a biopsy specimen from the lesion is shown. Which of the following is the most likely causal organism?", "answer": "Leishmania braziliensis", "options": {"A": "Treponema pallidum", "B": "Trypanosoma brucei", "C": "Ancylostoma duodenale", "D": "Borrelia burgdorferi", "E": "Leishmania braziliensis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old woman comes to the physician because of a 1-month history of episodic cough and shortness of breath. The cough is nonproductive and worsens when she climbs stairs and during the night. She has not had chest pain or palpitations. Eight weeks ago, she had fever, sore throat, and nasal congestion. She has a 10-year history of hypertension. She has smoked half a pack of cigarettes daily for 16 years. Her only medication is enalapril. Her pulse is 78/min, respirations are 18/min, and blood pressure is 145/95 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Diffuse end-expiratory wheezes are heard on pulmonary auscultation. An x-ray of the chest shows no abnormalities. Spirometry shows an FEV1:FVC ratio of 65% and an FEV1 of 60%. Which of the following is the most likely diagnosis?", "answer": "Asthma", "options": {"A": "Pneumonia", "B": "Gastroesophageal reflux disease", "C": "Side effect of medication", "D": "Asthma", "E": "Chronic bronchitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2850-g (6-lb 5-oz) newborn is delivered at term to a 19-year-old primigravid woman via normal spontaneous vaginal delivery. The mother has had no prenatal care. Examination of the newborn in the delivery room shows a small, retracted jaw and hypoplasia of the zygomatic arch. This patient's condition is most likely caused by abnormal development of the structure that also gives rise to which of the following?", "answer": "Incus", "options": {"A": "Facial nerve", "B": "Cricothyroid muscle", "C": "Incus", "D": "Greater horn of hyoid", "E": "Platysma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old woman comes to the emergency department because of epigastric abdominal pain that started after her last meal and has become progressively worse over the past 6 hours. She has had intermittent pain similar to this before, but it has never lasted this long. Her temperature is 39°C (102.2°F). Examination shows a soft abdomen with normal bowel sounds. The patient has sudden inspiratory arrest during right upper quadrant palpation. Her alkaline phosphatase, total bilirubin, amylase, and aspartate aminotransferase levels are within the reference ranges. Abdominal imaging is most likely to show which of the following findings?", "answer": "Gallstone in the cystic duct", "options": {"A": "Dilated common bile duct with intrahepatic biliary dilatation", "B": "Gallstone in the cystic duct", "C": "Fistula formation between the gallbladder and bowel", "D": "Decreased echogenicity of the liver", "E": "Enlargement of the pancreas with peripancreatic fluid"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old boy is brought to the physician by his father because he has been waking up frequently during the night to urinate. Apart from occasional headaches, he has no other complaints. His family recently emigrated from Tanzania and his medical history is unknown. His father was diagnosed with sickle cell disease at the age of 5. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14.5 g/dL\nHematocrit 44%\nMCV 90 fL\nReticulocytes 1.5%\nA hemoglobin electrophoresis shows:\nHbA 55%\nHbS 43%\nHbF 1%\nThis patient is at greatest risk for which of the following conditions?\"", "answer": "Renal papillary necrosis", "options": {"A": "Avascular osteonecrosis", "B": "Clear cell renal carcinoma", "C": "Renal papillary necrosis", "D": "Functional asplenia", "E": "Ischemic stroke\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 71-year-old woman comes to the physician because of an 8-month history of fatigue. Laboratory studies show a hemoglobin concentration of 13.3 g/dL, a serum creatinine concentration of 0.9 mg/dL, and a serum alkaline phosphatase concentration of 100 U/L. Laboratory evaluation of which of the following parameters would be most helpful in determining the cause of this patient's symptoms?", "answer": "Gamma-glutamyl transpeptidase", "options": {"A": "Cancer antigen 27-29", "B": "Lactate dehydrogenase", "C": "Ferritin", "D": "Gamma-glutamyl transpeptidase", "E": "Calcitriol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A laboratory physician investigates the chromosomes of a fetus with a suspected chromosomal anomaly. She processes a cell culture obtained by amniocentesis. Prior to staining and microscopic examination of the fetal chromosomes, a drug that blocks cell division is added to the cell culture. In order to arrest chromosomes in metaphase, the physician most likely added a drug that is also used for the treatment of which of the following conditions?", "answer": "Acute gouty arthritis", "options": {"A": "Trichomonas vaginitis", "B": "Acute gouty arthritis", "C": "Herpes zoster", "D": "Testicular cancer", "E": "Polycythemia vera"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Following gastric surgery, a 45-year-old woman complains of severe nausea and vomiting on the 2nd postoperative day. On physical examination, her vitals are stable and examination of the abdomen reveals no significant abnormality. The patient is already receiving a maximum dosage of ondansetron. Metoclopramide is given, and she experiences significant relief from nausea and vomiting. Which of the following best explains the mechanism of action of this drug?", "answer": "Inhibition of dopamine receptors in the area postrema", "options": {"A": "Inhibition of dopamine receptors in the area postrema", "B": "Inhibition of serotonin receptors on the nucleus tractus solitarius", "C": "Stimulation of motilin receptors in gastrointestinal smooth muscle", "D": "Enhancement of small intestinal and colonic motility by dopamine antagonism", "E": "Decreased esophageal peristaltic amplitude"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman is found unconscious on the office floor just before lunch by her colleagues. She had previously instructed them on the location of an emergency kit in case this ever happened so they are able to successfully inject her with the substance inside. Her past medical history is significant for type 1 diabetes for which she takes long acting insulin as well as periprandial rapid acting insulin injections. She has previously been found unconscious once before when she forgot to eat breakfast. The substance inside the emergency kit most likely has which of the following properties.", "answer": "Promotes gluconeogenesis in the liver", "options": {"A": "Inhibits activity of pancreatic alpha and beta cells", "B": "Promotes gluconeogenesis in the liver", "C": "Promotes glucose release from skeletal muscles", "D": "Promotes glucose uptake in muscles", "E": "Promotes glycogen formation in the liver"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 6-year-old girl is brought to the physician because of a generalized pruritic rash for 3 days. Her mother has noticed fluid oozing from some of the lesions. She was born at term and has been healthy except for an episode of bronchitis 4 months ago that was treated with azithromycin. There is no family history of serious illness. Her immunization records are unavailable. She attends elementary school but has missed the last 5 days. She appears healthy. Her temperature is 38°C (100.4°F). Examination shows a maculopapular rash with crusted lesions and vesicles over the entire integument, including the scalp. Her hemoglobin concentration is 13.1 g/dL, leukocyte count is 9800/mm3, and platelet count is 319,000/mm3. Which of the following is the most appropriate next best step?", "answer": "Calamine lotion", "options": {"A": "Vitamin A therapy", "B": "Rapid strep test", "C": "Tzanck test", "D": "Measles IgM titer", "E": "Calamine lotion"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-month-old boy is brought to the emergency room by his mother for 2 days of difficulty breathing. He was born at 35 weeks gestation but has otherwise been healthy. She noticed a cough and some trouble breathing in the setting of a runny nose. His temperature is 100°F (37.8°C), blood pressure is 64/34 mmHg, pulse is 140/min, respirations are 39/min, and oxygen saturation is 93% on room air. Pulmonary exam is notable for expiratory wheezing and crackles throughout and intercostal retractions. Oral mucosa is noted to be dry. Which of the following is the most appropriate diagnostic test?", "answer": "No further testing needed", "options": {"A": "Chest radiograph", "B": "No further testing needed", "C": "Polymerase chain reaction", "D": "Sputum culture", "E": "Viral culture"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2200-g (4-lbs 13-oz) female newborn is delivered at term to a 37-year-old gravida 2, para 1 woman. The newborn is at the 10th percentile for length, 14th percentile for weight, and 3rd percentile for head circumference. Examination shows “punched-out“ skin lesions on the scalp, cleft lip, and a small chin. There is a convex-shaped deformity of the plantar surface of the feet. Auscultation shows a holosystolic murmur heard best at the left lower sternal border. Some of her intestines protrude through the umbilicus, covered by a thin membranous sac. An MRI of the brain shows a single ventricle and a fusion of the basal ganglia. Which of the following additional findings is most likely to be seen in this patient?", "answer": "Polydactyly", "options": {"A": "Polydactyly", "B": "Webbed neck", "C": "Single palmar crease", "D": "Overlapping fingers", "E": "Hypoplastic philtrum"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 39-year-old woman presents to the emergency department with fever, cough, and shortness of breath. She reports developing flu-like symptoms 7 days ago but progressively worsened to the point where she experiences dyspnea on exertion. Her cough is accompanied by a mild amount of yellow sputum. Past medical history is notable for a previous admission to the hospital for pneumonia 4 months ago and an admission for bacteremia 6 weeks ago. She additionally has a history of IV heroin abuse, but her last use of heroin was 3 years ago. Temperature is 101.2°F (38.4°C), blood pressure is 104/70 mmHg, pulse is 102/min, and respirations are 20/min. Physical examination demonstrates coarse upper airway breath sounds over the right lower lung field. A faint 1/6 non-radiating systolic flow murmur is auscultated at the first right intercostal space. Abdominal examination is significant for moderate splenomegaly. Tenderness of the wrists and fingers is elicited on palpation, and range of motion is restricted. The patient comments that her range of motion and pain usually improve as the day goes on. Which of the following laboratory abnormalities is most likely to be found in this patient?", "answer": "Neutropenia", "options": {"A": "Decreased anion gap", "B": "Flow cytometry positive for CD11c and CD2", "C": "Leukocytosis with left-shift", "D": "Neutropenia", "E": "Positive HIV serology"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old man presents to his primary care physician complaining of pain and bulging in his groin. He is otherwise healthy and has never had surgery. He is referred to a general surgeon, and is scheduled for an elective hernia repair the following week. On closer inspection in the operating room, the surgeon notes a hernia sac that protrudes through the external inguinal ring, bypassing the inguinal canal. Which of the following accurately describes this patient's condition?", "answer": "Direct inguinal hernia", "options": {"A": "Direct hiatal hernia", "B": "Indirect femoral hernia", "C": "Direct incisional hernia", "D": "Isolated rectus diastasis", "E": "Direct inguinal hernia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man comes to the physician for evaluation of a neck mass and weight loss. He first noticed the growing mass 2 months ago. The mass is not painful. He also has decreased appetite and intermittent abdominal pain. He has lost 10 kg (22 lb) of weight over the past 3 months. Sometimes, he wakes up in the morning drenched in sweat. He takes daily over-the-counter multivitamins. He appears pale. His pulse is 65/min, blood pressure is 110/70 mm Hg, and temperature is 38.1°C (100.6°F). Physical exam shows a painless, golf ball-sized mass in the anterior triangle of the neck. A biopsy shows large cells with a bilobed nucleus that are CD15- and CD30-positive. Laboratory analysis of serum shows a calcium level of 14.5 mg/dL and a parathyroid hormone level of 40 pg/mL. Which of the following is the most likely explanation of this patient's laboratory findings?", "answer": "Ectopic vitamin D production", "options": {"A": "Osteoblastic metastasis", "B": "Ectopic vitamin D production", "C": "Ectopic PTH-related protein production", "D": "Multivitamin overdose", "E": "Osteolytic metastasis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 29-year-old African American woman presents with incidentally noted bilateral hilar lymphadenopathy on a recent chest radiograph for the evaluation of pneumonia 1 month earlier. Upon questioning, she reports a cough, dyspnea, and angina. The report provided by a previous ophthalmologic consultation did not demonstrate any eye abnormalities. Clinical laboratory pathologic analysis reveals an elevated level of angiotensin-converting enzyme. Her physical examination reveals no obvious abnormalities. Her vital signs show a heart rate of 76/min, respiratory rate of 16/min, and blood pressure of 123/73 mm Hg. Of the following options, which is the mechanism of the reaction causing hilar adenopathy in this patient?", "answer": "Type IV–cell-mediated (delayed) hypersensitivity reaction", "options": {"A": "Type I–anaphylactic hypersensitivity reaction", "B": "Type II–cytotoxic hypersensitivity reaction", "C": "Type III–immune complex-mediated hypersensitivity reaction", "D": "Type IV–cell-mediated (delayed) hypersensitivity reaction", "E": "Type III and IV–mixed immune complex and cell-mediated hypersensitivity reactions"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Ten days after starting a new medication, a 60-year-old man is brought to the emergency department after a 3-minute episode of myoclonic jerking movements and urinary incontinence. After regaining consciousness, the patient had no recollection of what happened and seemed confused. He has bipolar disorder, which has been controlled with maintenance therapy for the past 15 years. Physical examination shows dry oral mucosa, muscle fasciculations, and bilateral hand tremors. His speech is slow, and he is disoriented. Which of the following drugs most likely precipitated this patient's current condition?", "answer": "Celecoxib", "options": {"A": "Valproic acid", "B": "Theophylline", "C": "Fluoxetine", "D": "Celecoxib", "E": "Metoprolol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 2-year-old boy is brought to the emergency department because of a 2-day history of fever and pain in the left lower extremity. His mother says that he has refused to walk for the last two days and has had a poor appetite. He returned from a weekend camping trip about a month ago. His maternal cousin died of osteosarcoma at the age of 12. His immunizations are up-to-date. He is at the 80th percentile for height and 70th percentile for weight. He appears ill. His temperature is 39.3°C (102.7°F), pulse is 115/min, respirations are 19/min, and blood pressure is 95/50 mm Hg. Examination of the left hip shows tenderness; range of motion is limited. Minimal attempts to rotate the hip cause severe discomfort. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12 g/dL\nLeukocyte count 19,800/mm3\nPlatelet count 254,000/mm3\nErythrocyte sedimentation rate 55 mm/h\nSerum\nGlucose 80 mg/dL\nCRP 15 mg/L\nX-rays of the pelvis shows a widened acetabular space on the left side. Which of the following is the most appropriate next step in management?\"", "answer": "Synovial fluid drainage plus cefazolin therapy", "options": {"A": "Vancomycin therapy", "B": "Synovial fluid drainage plus cefazolin therapy", "C": "Trimethoprim/sulfamethoxazole therapy", "D": "Arthroscopic drainage of hip", "E": "Doxycycline therapy\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 51-year-old male presents to his primary care provider for a normal check-up. He reports that he “hasn’t felt like himself” recently. He describes feeling down for the past 8 months since his mother passed away. He has had trouble sleeping and has unintentionally lost 15 pounds. He feels guilty about his mother’s death but cannot articulate why. His performance at work has declined and he has stopped running, an activity he used to enjoy. He has not thought about hurting himself or others. Of note, he also complains of numbness in his feet and fingers and inability to maintain an erection. His past medical history is notable for diabetes. He is on metformin. His temperature is 98.6°F (37°C), blood pressure is 125/65 mmHg, pulse is 90/min, and respirations are 16/min. On exam, he is alert and oriented with intact memory and normal speech. He appears tired with a somewhat flattened affect. The best medication for this patient inhibits which of the following processes?", "answer": "Norepinephrine and serotonin reuptake", "options": {"A": "Serotonin reuptake only", "B": "Norepinephrine and serotonin reuptake", "C": "Amine degradation", "D": "Norepinephrine and dopamine reuptake", "E": "Dopamine receptor activation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old man arrives at the emergency department within minutes after a head-on motor vehicle accident. He suffered from blunt abdominal trauma, several lacerations to his face as well as lacerations to his upper and lower extremities. The patient is afebrile, blood pressure is 45/25 mmHg and pulse is 160/minute. A CBC is obtained and is most likely to demonstrate which of the following?", "answer": "Hb 15 g/dL, Hct 45%", "options": {"A": "Hb 5 g/dL, Hct 20%", "B": "Hb 5 g/dL, Hct 30%", "C": "Hb 15 g/dL, Hct 45%", "D": "Hb 20 g/dL, Hct 60%", "E": "Hb 17 g/dL, Hct 20%"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old man comes to the physician because of a 3-month history of pain in his left shoulder. He is physically active and plays baseball twice a week. The pain is reproduced when the shoulder is externally rotated against resistance. Injury of which of the following tendons is most likely in this patient?", "answer": "Infraspinatus", "options": {"A": "Teres major", "B": "Pectoralis major", "C": "Infraspinatus", "D": "Supraspinatus", "E": "Subscapularis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old woman presents to the physician with a throbbing headache. She says she had it for the last year and it’s usually located in the right temporal area. There is localized tenderness over the scalp. During the last 2 weeks, she experienced 3 episodes of transient loss of vision on the right side, without ocular pain. On physical examination, her vital signs are normal. Palpation reveals that the pulsations of the superficial temporal artery on the right side are reduced in amplitude. Laboratory studies show:\nBlood hemoglobin 10.7 g/dL (6.64 mmol/L)\nLeukocyte count 8,000/mm3 (8.0 x 109/L)\nPlatelet count 470,000/mm3 (470 x 109/L)\nErythrocyte sedimentation rate 60 mm/h (60 mm/h)\nWhich of the following conditions is most likely to co-exist with the presenting complaint in this woman?", "answer": "Polymyalgia rheumatica", "options": {"A": "Amyloidosis", "B": "Dermatomyositis", "C": "Fibromyalgia", "D": "Polymyalgia rheumatica", "E": "Sjogren’s syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A researcher is studying proteins that contribute to intestinal epithelial permeability. He has isolated intestinal tissue from several mice. After processing the tissue into its individual components, he uses a Western blot analysis to identify a protein that forms part of a multi-protein complex at the apical aspect of epithelial cells. The complex is known to provide a diffusion barrier between the apical and basolateral aspects of epithelial cells. Which of the following proteins is this researcher most likely investigating?", "answer": "Claudin", "options": {"A": "Integrin", "B": "Connexon", "C": "Desmoglein", "D": "E-cadherin", "E": "Claudin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 38-year-old woman is evaluated for a difficult-to-control hypertension. Her symptoms include sleep interruption because of frequent waking up for voiding and frequent headaches. She has smoked 10 cigarettes daily for the past 5 years. Family history is insignificant. Her vital signs include a blood pressure of 170/96 mm Hg, pulse of 90/min, and temperature of 36.7°C (98.0°F). Physical examination is unremarkable. Her lab results are shown:\nSerum sodium 146 mEq/L\nSerum potassium 4 mEq/L\nSerum bicarbonate 29 mEq/L\nHer plasma aldosterone concentration (PAC): plasma renin activity (PRA) ratio measured after following all precautions is found to be elevated. Oral salt loading testing reveals a lack of aldosterone suppression. A computerized tomography (CT) scan of the adrenal glands shows a 2 cm mass on the left side. Which of the following is the best next step for this patient?", "answer": "Adrenal venous sampling", "options": {"A": "Renal angiogram", "B": "Adrenal venous sampling", "C": "Measurement of 11-deoxycortisol", "D": "Left laparoscopic adrenalectomy", "E": "Treatment with eplerenone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old woman comes to the office with a 3-day history of a rash. She's had a rash across her neck, shoulders, and the palms of her hands for the past five days. She's also had large-volume watery diarrhea for the same period of time. Past medical history is notable for acute myeloid leukemia, for which she received a stem cell transplant from a donor about two months prior. Physical exam reveals a faint red maculopapular rash across her neck, shoulders, and hands, as well as an enlarged liver and spleen. Labs are notable for a total bilirubin of 10. Which of the following is the mechanism of this patient's pathology?", "answer": "Graft T cells against host antigens", "options": {"A": "Drug hypersensitivity reaction", "B": "Pre-existing host antibodies against graft antigens", "C": "Host antibodies that have developed against graft antigens", "D": "Host CD8+ T cells against graft antigens", "E": "Graft T cells against host antigens"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old man who recently emigrated as a refugee from Somalia presents with fever, weight loss, fatigue, and exertional chest pain. He says his symptoms began 3 weeks ago and that his appetite has decreased and he has lost 3 kg (6.6 lb) in the last 3 weeks. He denies any history of cardiac disease. His past medical history is unremarkable. The patient admits that he has always lived in poor hygienic conditions in overcrowded quarters and in close contact with cats. His vital signs include: blood pressure 120/60 mm Hg, pulse 90/min, and temperature 38.0°C (100.4°F). Physical examination reveals generalized pallor. A cardiac examination reveals an early diastolic murmur loudest at the left third intercostal space. Abdominal examination reveals a tender and mildly enlarged spleen. Prominent axillary lymphadenopathy is noted. Laboratory investigations reveal a WBC count of 14,500/μL with 5% bands and 93% polymorphonuclear cells. An echocardiogram reveals a 5-mm vegetation on the aortic valve with moderate regurgitation. Three sets of blood cultures are taken over 24 hours followed by empiric antibiotic therapy with gentamicin and vancomycin. The blood cultures show no growth after 5 days. Following a week of empiric therapy, the patient continues to deteriorate. Which of the following would most likely confirm the diagnosis in this patient?", "answer": "Bartonella serology", "options": {"A": "Bartonella serology", "B": "Q fever serology", "C": "Peripheral blood smear", "D": "HIV polymerase chain reaction", "E": "Epstein-Barr virus heterophile antibody"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Four days after having been admitted to the hospital for a pulmonary contusion and whiplash injury sustained in a motor vehicle collision, a 66-year-old woman complains of severe pain in her right flank and muscle spasms. She also has nausea with two episodes of vomiting and abdominal bloating. Her pain had previously been well controlled with acetaminophen every 6 hours. She underwent umbilical hernia repair surgery two years ago. She takes sertraline for depression. Her temperature is 36.5°C (97.7°F), pulse is 99/min, respirations are 17/min, and blood pressure is 102/72 mm Hg. After administration of 0.5 L of crystalloid fluids, blood pressure improves to 118/79 mm Hg. Multiple ecchymoses are present over the anterior abdominal wall in a pattern that follows the course of a seatbelt. There are ecchymoses of the flanks bilaterally. Bowel sounds are absent. There is tenderness to palpation in all four quadrants with voluntary guarding. Her hemoglobin is 7.9 g/dL, leukocyte count is 8,500/mm3, platelet count is 350,000/mm3, prothrombin time is 11 seconds, and activated partial thromboplastin time is 33 seconds. An x-ray of the abdomen shows obliteration of the right psoas shadow and uniform distribution of gas in the small bowel, colon, and rectum without air-fluid levels. Which of the following is the most likely explanation for this patient's symptoms?", "answer": "Retroperitoneal hemorrhage", "options": {"A": "Small bowel perforation", "B": "Intraabdominal adhesions", "C": "Spinal cord injury", "D": "Retroperitoneal hemorrhage", "E": "Acute mesenteric ischemia\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old man comes to the physician because of a 2-week history of chest pain that begins after walking at a brisk pace for 2 blocks. The pain does not radiate anywhere and is hard to localize. He has had similar episodes in the past 6 months and was prescribed sublingual nitroglycerin, which helps relieve the pain. The patient has hypertension and type 2 diabetes mellitus. He takes lisinopril and metformin daily. He appears well. His temperature is 37°C (98.6°F), pulse is 75/min, and blood pressure is 145/90 mm Hg. Examination shows a regular heart rhythm. S1 and S2 are normal. The lungs are clear to auscultation. There is no peripheral edema. Which of the following is the most likely explanation for the improvement of this patient's chest pain?", "answer": "Decreased end-diastolic pressure\n\"", "options": {"A": "Delayed electrical conduction", "B": "Decreased venous pooling", "C": "Coronary arterial vasodilation", "D": "Increased atherosclerotic plaque stability", "E": "Decreased end-diastolic pressure\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 34-year-old woman presents with confusion, drowsiness, and headache. The patient’s husband says her symptoms began 2 days ago and have progressively worsened with an acute deterioration of her mental status 2 hours ago. The patient describes the headaches as severe, localized to the frontal and periorbital regions, and worse in the morning. Review of symptoms is significant for a mild, low-grade fever, fatigue, and nausea for the past week. Past medical history is significant for HIV infection for which she is not currently receiving therapy. Her CD4+ T cell count last month was 250/mm3. The blood pressure is 140/85 mm Hg, the pulse rate is 90/min, and the temperature is 37.7°C (100.0°F). On physical examination, the patient is conscious but drowsy. Papilledema is present. No pain is elicited with extension of the leg at the knee joint. The remainder of the physical examination is negative. Laboratory findings, including panculture, are ordered. A noncontrast CT scan of the head is negative and is followed by a lumbar puncture. CSF analysis is significant for:\nOpening pressure 250 mm H2O (70-180 mm H2O)\nGlucose 30 mg/dL (40-70 mg/dL)\nProtein 100 mg/dL (<40 mg/dL)\nCell count 20/mm3 (0-5/mm3)\nWhich of the following additional findings would most likely be found in this patient?", "answer": "CSF India ink stain shows encapsulated yeast cells", "options": {"A": "CSF shows a positive acid-fast bacillus stain", "B": "CSF shows gram negative diplococci", "C": "CSF India ink stain shows encapsulated yeast cells", "D": "Gram-positive diplococci are present on microscopy", "E": "Multiple ring-enhancing lesions are seen on a CT scan"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old male is started on nitrate therapy for treatment of stable angina. He experiences significant and immediate relief of his symptoms within minutes of starting therapy. Approximately 48 hours after initiating this new medication, he notes return of chest pain and pressure with exertion that no longer responds to continued nitrate use. Which of the following 24-hour dosing schedules would most likely explain this patient's response to nitrate treatment?", "answer": "Transdermal nitroglycerin patch placed at 7AM then removed and replaced with another at 7PM", "options": {"A": "Transdermal nitroglycerin patch placed at 7AM then removed and replaced with another at 7PM", "B": "PO regular-release isosorbide dinitrate taken at 8AM, noon, and 5PM", "C": "Transdermal nitroglycerin patch placed at bedtime and removed at 7AM without replacement", "D": "Transdermal nitroglycerin patch placed upon awakening in the morning and removed at 7PM without replacement", "E": "PO extended release isosorbide-5-mononitrate once daily at 8AM"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old woman comes to the physician for a follow-up visit for elevated blood pressure. Two weeks ago, her blood pressure was 154/78 mm Hg at a routine visit. Subsequent home blood pressure measurements at days 5, 10, and 14 have been: 156/76 mm Hg, 158/80 mm Hg, and 160/80 mm Hg. She has trouble falling asleep but otherwise feels well. She had a cold that resolved with over-the-counter medication 2 weeks ago. She has a history of primary hypothyroidism and a cyst in the right kidney, which was found incidentally 20 years ago. She takes levothyroxine. She is 178 cm (5 ft 10 in) tall and weighs 67 kg (148 lb); BMI is 21.3 kg/m2. Her pulse is 82/min, and blood pressure is 162/79 mm Hg. Examination shows no abnormalities. Laboratory studies, including thyroid function studies, serum electrolytes, and serum creatinine, are within normal limits. Which of the following is the most likely underlying cause of this patient's blood pressure findings?", "answer": "Decrease in arterial compliance", "options": {"A": "Increase in kidney size", "B": "Decrease in arterial compliance", "C": "Medication-induced vasoconstriction", "D": "Decrease in baroreceptor sensitivity", "E": "Increase in aldosterone production"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 9-month-old infant is brought to the physician because of a generalized nonpruritic rash for 2 days. The rash began on her trunk and spread to her extremities. Five days ago, she was taken to the emergency department for fever of 40.5°C (104.9°F) and a 1-minute generalized tonic-clonic seizure. She was born at term and has no history of serious illness. Her immunizations are up-to-date. Current medications include acetaminophen. Her temperature is 37.2°C (99.0°F) and pulse is 120/min. Examination shows a maculopapular rash that blanches on pressure. A photograph of the rash is shown. Posterior auricular lymphadenopathy is present. Which of the following is the most likely diagnosis?", "answer": "Roseola infantum", "options": {"A": "Kawasaki disease", "B": "Drug allergy", "C": "Impetigo", "D": "Roseola infantum", "E": "Rubella"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 11-month-old boy is brought to the physician by his adoptive mother for the evaluation of seizures and musty-smelling urine. His immunizations are up-to-date. His height and weight are both below the 10th percentile. He is pale and has blue eyes. He cannot pull himself up from a seated position to stand and does not crawl. Which of the following genetic principles best explains the variety of phenotypic traits seen in this patient?", "answer": "Pleiotropy", "options": {"A": "Variable expressivity", "B": "Pleiotropy", "C": "Incomplete penetrance", "D": "Anticipation", "E": "Loss of heterozygosity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old woman is in the intensive care unit for the management of a severe acute asthma exacerbation. She is currently intubated and sedated, and she is receiving intravenous steroids, continuous nebulized beta-agonists, and anticholinergic therapy via breathing treatments. On hospital day 2, she has a new fever to 38.9°C (102.0°F). Chest X-ray shows a right lower lobe consolidation. Blood cultures are collected, and she is started empirically on intravenous cefepime and daptomycin. On hospital day 4, she continues to be febrile; chest X-ray shows interval worsening of the right lower lobe opacity. Which of the following is the most likely reason for treatment failure in this patient?", "answer": "Inactivation of the medicine in the target tissue", "options": {"A": "Abnormally rapid clearance of the medicines by the kidney", "B": "Abnormally rapid metabolism of the medicines by the liver", "C": "Inactivation of the medicine in the target tissue", "D": "Low bioavailability of the medicines", "E": "Poor delivery of the medicines to the target tissue"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 53-year-old Asian woman comes to the physician because of a 2-month history of severe pain in her right leg while walking. She used to be able to walk a half-mile (800-m) to the grocery store but has been unable to walk 200 meters without stopping because of the pain over the past month. She can continue to walk after a break of around 5 minutes. She has hypertension, atrial fibrillation, and type 2 diabetes mellitus. She has smoked one pack of cigarettes daily for the past 32 years. Current medications include metformin, enalapril, aspirin, and warfarin. Vital signs are within normal limits. Examination shows an irregularly irregular pulse. The right lower extremity is cooler than the left lower extremity. The skin over the right leg appears shiny and dry. Femoral pulses are palpated bilaterally; pedal pulses are diminished on the right side. Which of the following is the most appropriate next step in management?", "answer": "Ankle-brachial index", "options": {"A": "MRI spine screening", "B": "Duplex ultrasonography", "C": "Nerve conduction studies", "D": "Ankle-brachial index", "E": "Biopsy of tibial artery"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old woman develops progressive difficulty breathing after a long day of chores in a dusty house. These chores included brushing the family dog, vacuuming, dusting, and sweeping. She occasionally gets these episodes once or twice a year and has her medication on hand. Her symptoms are reversed by inhaling a β2-adrenergic receptor agonist. Which of the following chemical mediators is responsible for this patient’s breathing difficulties?", "answer": "Leukotrienes", "options": {"A": "Bradykinin", "B": "Leukotrienes", "C": "Endorphins", "D": "Serotonin", "E": "Histamine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Nine healthy subjects participate in a study of gastric secretions. Subjects are asked to eat a meal at hour 0, at which time the pH of stomach contents and rate of stomach acid secretions are measured over the next 4 hours. Results of the study are shown. Which of the following mediators is most active at point A in the graph?", "answer": "Acetylcholine", "options": {"A": "Prostaglandin", "B": "Secretin", "C": "Somatostatin", "D": "Glucose-dependent insulinotropic peptide", "E": "Acetylcholine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 43-year-old Caucasian woman is admitted to the hospital with acute onset right upper quadrant (RUQ) pain. The pain started 6 hours ago after the patient had a large meal at a birthday party and has progressively worsened. She recalls having similar pain before but not so intense. No significant past medical history. Current medications are only oral contraceptive. Vitals are blood pressure 140/80 mm Hg, heart rate 79/min, respiratory rate 14/min, and temperature 37.6℃ (99.7℉). The patient’s BMI is 36.3 kg/m2. On exam, the patient appears slightly jaundiced. Her cardiac and respiratory examinations are within normal limits. Abdominal palpation reveals tenderness to palpation in the RUQ with no rebound or guarding, and there is an inspiratory arrest on deep palpation in this region. The remainder of the examination is within normal limits.\nLaboratory tests are significant for the following:\nRBC count 4.1 million/mm3\nHb 13.4 mg/dL\nLeukocyte count 11,200/mm3\nESR 22 mm/hr\nPlatelet count 230,000/mm3\nTotal bilirubin 2 mg/dL\nDirect bilirubin 1.1 mg/dL\nALT 20 IU/L\nAST 18 IU/L\nAmylase 33 IU/L\nUltrasound of the abdomen shows the following result (see image):\nThe common bile duct (CBD) (not shown in the image) is not dilated. Which of the following procedures is most appropriate for the treatment of this patient?", "answer": "Laparoscopic cholecystectomy", "options": {"A": "Open cholecystectomy", "B": "Endoscopic retrograde cholangiopancreatography", "C": "Laparoscopic cholecystectomy", "D": "Percutaneous cholecystostomy", "E": "Shock wave lithotripsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old man comes to the physician because of severe muscle pain and swelling of his eyelids for 3 days. He has also had fever and chills during this period. For the last 2 days, he has had severe pain in his mouth while chewing. He had an episode of diarrhea a month ago for which he did not seek medical care. He has no history of serious illness. His sister has dermatomyositis. He returned from a hunting trip to eastern Europe 45 days ago. His temperature is 38.1°C (100.6°F), pulse is 80/min, and blood pressure is 130/70 mm Hg. Examination shows periorbital edema and severe generalized muscle tenderness. There are splinter hemorrhages on both hands. Laboratory studies show:\nHemoglobin 14.2 g/dL\nLeukocyte count 12,500/mm3\nSegmented neutrophils 60%\nEosinophils 18%\nLymphocytes 20%\nMonocytes 2%\nSerum\nGlucose 117 mg/dL\nCreatinine 1.1 mg/dL\nAlkaline phosphatase 72 U/L\nCreatine kinase 765 U/L\nUrinalysis is within normal limits. Which of the following is most likely to have prevented this patient's condition?\"", "answer": "Cooking meat to 71°C (160°F)", "options": {"A": "Clean drinking water", "B": "Cooking meat to 71°C (160°F)", "C": "Influenza vaccine", "D": "Consume pasteurized dairy products", "E": "Metronidazole at the onset of diarrhea"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old man comes to the physician for a pre-employment examination. He has no history of serious illness and takes no medications. A screening blood test is performed in which peptides are added to the sample to stimulate in vitro production of interferon-gamma, which is then measured using an enzyme-linked immunosorbent assay. This test is most likely to be helpful in diagnosing infection with which of the following pathogens?", "answer": "Mycobacterium tuberculosis", "options": {"A": "Human immunodeficiency virus", "B": "Staphylococcus aureus", "C": "Hepatitis B virus", "D": "Mycobacterium tuberculosis", "E": "Legionella pneumophila"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman comes to the physician because of a 5-month history of a pruritic rash on the bilateral upper extremities. She has no history of serious illness and takes no medications. A skin biopsy of the rash shows intraepidermal accumulation of edematous fluid and widening of intercellular spaces between keratinocytes. Which of the following is the most likely diagnosis?", "answer": "Eczematous dermatitis", "options": {"A": "Psoriasis vulgaris", "B": "Lichen planus", "C": "Dermatitis herpetiformis", "D": "Acanthosis nigricans", "E": "Eczematous dermatitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old man with a 20+ year history of smoking comes in today to talk about quitting. His wife has recently been trying to quit, and she wants him to quit with her. He has been resistant in the past, but he is now very willing to talk with you about it. Today, he seems like he really wants to make a change. What stage of change does this behavior correspond to?", "answer": "Preparation", "options": {"A": "Precontemplation", "B": "Contemplation", "C": "Preparation", "D": "Action", "E": "Maintenance"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old woman is brought into the clinic by her husband with concerns that she might be depressed. She delivered a healthy newborn a week and a half ago without any complications. Since then, she has been having trouble sleeping, eating poorly, and has stopped playing with the baby. The patient says she feels like she is drained all the time and feels guilty for not doing more for the baby. Which of the following is the best course of treatment for this patient?", "answer": "Reassurance", "options": {"A": "Reassurance", "B": "Fluoxetine", "C": "Amitriptyline ", "D": "Risperidone", "E": "No treatment"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old man presents to the emergency department with complaints of upper abdominal pain for the last several hours. He says that the pain travels to his back and is less severe when he leans forward. He is diagnosed with acute pancreatitis following enzyme analysis and CT scan of the abdomen and is subsequently managed in intensive care unit (ICU) with IV fluids, analgesics, nasogastric decompression, and supportive therapy. He recovers quickly and is discharged within a week. However, after 5 weeks, the patient develops projectile vomiting containing food but no bile. Physical examination shows visible peristalsis from left to right in the upper abdomen. A repeat CT scan is done. Which of the following is the next best step in the management of this patient?", "answer": "Endoscopic drainage", "options": {"A": "Need no management as this will resolve spontaneously", "B": "Octreotide infusion to reduce all gastrointestinal secretions", "C": "External percutaneous drainage of the lesion", "D": "Endoscopic drainage", "E": "Intravenous fluids, analgesia, and antiemetics"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 13-year-old boy is brought to the physician because of a 5-day history of a rash on his chest and back. His mother initially noticed only a few lesions on his back, but since then the rash has spread to his chest. His family returned from a trip to the Caribbean 2 weeks ago. His mother started using a new laundry detergent 8 days ago. He has type 1 diabetes mellitus controlled with insulin. His mother has Hashimoto thyroiditis and his brother has severe facial acne. His temperature is 37.2°C (99°F), pulse is 81/min, and blood pressure is 115/74 mm Hg. Examination of the skin shows multiple, nontender, round, white macules on the chest and trunk. There is fine scaling when the lesions are scraped with a spatula. There are no excoriation marks. The remainder of the examination shows no abnormalities. Which of the following is the most likely underlying mechanism of this patient's symptoms?", "answer": "Increased growth of Malassezia globosa", "options": {"A": "Autoimmune destruction of melanocytes", "B": "Increased sebum production", "C": "Increased growth of Malassezia globosa", "D": "Exposure to human herpes virus 7", "E": "Antigen uptake by Langerhans cells"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old woman is brought to the emergency department because of increasing abdominal pain for 6 hours. The pain is dull and diffuse over her abdomen and radiates to her lower back bilaterally. Three weeks ago, she was diagnosed with atrial fibrillation and started on warfarin. Her only other medication is 1 g of acetaminophen daily for osteoarthritis of her knees. Her pulse is 87/min and blood pressure is 112/75 mm Hg. Physical examination shows abdominal tenderness to palpation at both lower quadrants. A CT scan of the abdomen shows a retroperitoneal mass and hazy margins of the surrounding structures. In addition to discontinuation of warfarin, the most appropriate next step in management is administration of which of the following?", "answer": "Phytonadione and prothrombin complex concentrate", "options": {"A": "Fresh frozen plasma and tranexamic acid", "B": "Aminocaproic acid and packed red blood cells", "C": "Factor VIII and von Willebrand factor", "D": "Phytonadione and prothrombin complex concentrate", "E": "Protamine sulfate and hydroxyethyl starch"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old man presents to a psychiatrist for management of nicotine dependence. He has been a heavy smoker for the past 20 years. He has unsuccessfully attempted to quit smoking many times. He has seen multiple physicians for nicotine dependence. They prescribed nicotine replacement therapy and varenicline. He has also taken two antidepressants and participated in talk therapy. He asks the psychiatrist whether there are other alternatives. The psychiatrist explains that nicotine replacement therapy, non-nicotine pharmacotherapy, and talk therapy are the best options for the management of nicotine dependence. He tells the patient he can take a second-line medication for non-nicotine pharmacotherapy because the first-line medication failed. Which of the following medications would the psychiatrist most likely use to manage this patient’s nicotine dependence?", "answer": "Clonidine", "options": {"A": "Buprenorphine", "B": "Clonidine", "C": "Lorazepam", "D": "Methadone", "E": "Topiramate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A physician attempts to study cirrhosis in his state. Using a registry of admitted patients over the last 10 years at the local hospital, he isolates all patients who have been diagnosed with cirrhosis. Subsequently, he contacts this group of patients, asking them to complete a survey assessing their prior exposure to alcohol use, intravenous drug abuse, blood transfusions, personal history of cancer, and other medical comorbidities. An identical survey is given to an equal number of patients in the registry who do not carry a prior diagnosis of cirrhosis. Which of the following is the study design utilized by this physician?", "answer": "Case-control study", "options": {"A": "Case-control study", "B": "Cohort study", "C": "Cross-sectional study", "D": "Meta-analysis", "E": "Randomized controlled trial"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old male presents to your office complaining of polyuria, polydipsia, and unintentional weight loss of 12 pounds over the past 3 months. On physical examination, the patient is tachypneic with labored breathing. Which of the following electrolyte abnormalities would you most likely observe in this patient?", "answer": "Hyperkalemia", "options": {"A": "Alkalemia", "B": "Hyperkalemia", "C": "Hypoglycemia", "D": "Hypermagnesemia", "E": "Hyperphosphatemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old man comes to the physician because of generalized fatigue and numbness of his legs and toes for 5 months. He has hypertension and hypercholesterolemia. He underwent a partial gastrectomy for peptic ulcer disease 15 years ago. Current medications include amlodipine and atorvastatin. He is a painter. His temperature is 37°C (98.6°F), pulse is 101/min, respirations are 17/min, and blood pressure is 122/82 mm Hg. Examination shows conjunctival pallor and glossitis. Sensation to vibration and position is absent over the lower extremities. He has a broad-based gait. The patient sways when he stands with his feet together and closes his eyes. His hemoglobin concentration is 10.1 g/dL, leukocyte count is 4300/mm3, and platelet count is 110,000/mm3. Which of the following laboratory findings is most likely to be seen in this patient?", "answer": "Elevated methylmalonic acid levels", "options": {"A": "Decreased serum iron levels", "B": "Oligoclonal bands in cerebrospinal fluid", "C": "Elevated methylmalonic acid levels", "D": "Basophilic stippling on peripheral smear", "E": "Positive rapid plasma reagin test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old male is brought to his pediatrician after recurrent, prolonged upper respiratory infections over a period of several months. Physical exam reveals petechiae on the patient’s legs and arms. Laboratory studies show hemoglobin: 10 g/L, platelet count: 35,000/mm^3, leukocyte count: 6,600/mm^3. A bone marrow aspiration shows an abundance of lymphoblasts indicative of acute lymphoblastic leukemia (ALL). Positive immunostaining for which of the following would support a diagnosis of precursor B-cell leukemia?", "answer": "CD19, CD10", "options": {"A": "TdT, HER-2", "B": "CD2, CD8", "C": "CD19, CD10", "D": "CD30, CD15", "E": "CD4, CD5"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "The objective of one case-control study was to assess whether a history of past trauma represents a risk factor for the development of spondyloarthritis. Cases of spondyloarthritis were compared with a random sample taken from the general population in regards to a history of prior trauma. This kind of history, which in turn increased the likelihood of being subjected to X-ray imaging investigations, led to a higher likelihood of diagnosing spondyloarthritis in these individuals compared with the general population. This resulted in a significantly higher proportion of spondyloarthritis in study participants with prior trauma, with the resulting overestimation of related odds ratio. In which case is the bias in this example more likely to occur?", "answer": "If the outcome is ascertained through electronic health records", "options": {"A": "If the outcome is ascertained through electronic health records", "B": "If the outcome is assessed systematically regardless of exposure", "C": "If the outcome is ascertained while the exposed status is masked", "D": "If the study participants are followed at the same time intervals", "E": "If the study participants are subjected to identical tests at each visit"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old man presents to the emergency department with trouble urinating. The patient states that in general he has had difficulty urinating but recently, it has taken significant effort for him to initiate a urinary stream. He finds himself unable to completely void and states he has suprapubic tenderness as a result. These symptoms started suddenly 3 days ago. The patient has a history of benign prostatic hyperplasia, constipation, and diabetes mellitus. His current medications include finasteride, sodium docusate, and hydrochlorothiazide. He recently started taking phenylephrine for seasonal allergies. The patient’s last bowel movement was 2 days ago. His temperature is 99.0°F (37.2°C), blood pressure is 167/98 mmHg, pulse is 90/min, respirations are 14/min, and oxygen saturation is 100% on room air. Physical exam is notable for suprapubic tenderness, and an ultrasound reveals 750 mL of fluid in the bladder. Which of the following is the most likely etiology of this patient’s symptoms?", "answer": "Medication-induced symptoms", "options": {"A": "Constipation", "B": "Medication-induced symptoms", "C": "Prostatic adenocarcinoma", "D": "Urinary tract infection", "E": "Worsening benign prostatic hypertrophy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old woman, gravida 2, para 1, at 26 weeks’ gestation, comes to the emergency department because of pain and swelling in her right calf. Physical examination shows an increased circumference of the right calf. The leg is warm and tender on palpation. Dorsiflexion of the right foot elicits calf pain. An ultrasound of the right leg shows a noncompressible popliteal vein. Which of the following is the most appropriate pharmacotherapy for this patient's condition?", "answer": "Heparin", "options": {"A": "Aspirin", "B": "Clopidogrel", "C": "Heparin", "D": "Rivaroxaban", "E": "Warfarin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-year-old boy is brought to the physician by his mother because of generalized weakness and difficulty walking for the past month. Laboratory studies show a hemoglobin concentration of 6.6 g/dL, mean corpuscular volume of 74 μm3, platelet count of 150,000/mm3, and serum total bilirubin of 2 mg/dl. An MRI of the spine shows low signal intensity in all vertebral bodies and a small epidural mass compressing the spinal canal at the level of L1. A CT scan of the head shows osteopenia with widening of the diploic spaces in the skull. A biopsy of the epidural mass shows erythroid colonies with an abundance of megakaryocytes and myeloid cells. Which of the following is the most likely diagnosis?", "answer": "Beta-thalassemia\n\"", "options": {"A": "G6PD deficiency", "B": "Aplastic anemia", "C": "Lead poisoning", "D": "Multiple myeloma", "E": "Beta-thalassemia\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old woman comes to the physician because of weight gain, generalized weakness, and irregular menstrual cycles for the past 16 months. She began having symptoms of insomnia and depression 10 months ago. More recently, she has been having difficulties rising from a chair. She has a 2-year history of hypertension. Current medications include citalopram and hydrochlorothiazide. She is 168 cm (5 ft 6 in) tall and weighs 100 kg (220 lb). BMI is 36 kg/m2. Her pulse is 92/min, respirations are 18/min, and blood pressure is 134/76 mm Hg. She appears tired and has a full, plethoric face and central obesity. Examination of the skin shows violaceous linear striations on her lower abdomen. Two midnight serum cortisol studies show measurements of 288 μg/L and 253 μg/L (N < 90); a 24-hour urinary cortisol measurement was 395 μg (N < 300). Upon follow-up laboratory examination, the patient's serum ACTH levels were also elevated at 136 pg/mL (N = 7–50). Which of the following is the most appropriate next step in evaluation?", "answer": "High-dose dexamethasone suppression test", "options": {"A": "MRI of the head with contrast", "B": "Measure ACTH levels in inferior petrosal sinuses", "C": "High-dose dexamethasone suppression test", "D": "CT scan of the abdomen with contrast", "E": "Bilateral adrenalectomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 43-year-old woman is found in the hospital to have a plasma sodium concentration of 126 mg/dL. She was hospitalized after she expressed suicidal ideations and was started on a medication for major depressive disorder. Her past medical history is significant for diabetes for which she is currently taking metformin. Her blood pressure while in the hospital has been around 130/85 mmHg and she is not taking any other medications. Urinalysis shows a serum osmolality of 1085 mOsm/L. Which of the following best describes the cell bodies of the cells that are behaving abnormally in this patient?", "answer": "Located in the hypothalamus", "options": {"A": "Acidophils in the anterior pituitary", "B": "Basophils in the anterior pituitary", "C": "Chromophobes in the anterior pituitary", "D": "Located in the hypothalamus", "E": "Located in the posterior pituitary"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 41-year-old nulliparous woman comes to the physician for an annual pelvic examination and Pap smear. Over the past year she has been feeling healthy. She is sexually active and uses an intrauterine device with copper for contraception. She has smoked one pack of cigarettes daily for 20 years. She is 160 cm (5 ft 3 in) tall and weighs 88 kg (194 lb); BMI is 34.4 kg/m2. Bimanual pelvic examination shows an irregularly enlarged uterus. A transvaginal ultrasound reveals a singular 4 cm, hypoechoic mass inside the myometrial wall. Which of the following is the most likely cause of this finding?", "answer": "Leiomyoma", "options": {"A": "Leiomyoma", "B": "Endometrial cancer", "C": "Endometrial hyperplasia", "D": "Endometrial polyp", "E": "Uterine leiomyosarcoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 52-year-old man comes to the physician for a routine health maintenance examination. He feels well. His blood pressure is 125/70 mm Hg. His glomerular filtration rate is calculated to be 105 mL/min/1.73 m2 and glucose clearance is calculated to be 103 mL/min. This patient is most likely being treated with which of the following agents?", "answer": "Canagliflozin", "options": {"A": "Metformin", "B": "Canagliflozin", "C": "Ifosfamide", "D": "Glipizide", "E": "Acarbose"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 18-month-old boy is brought in by his parents for a routine check-up. The parents state that the patient still has not had any language development, and they are concerned about developmental delay. Of note, they have also noticed that the patient’s facial features have changed significantly in the last year. The patient also seems to have trouble visually focusing on objects or on the television. On exam, the patient's temperature is 98.2°F (36.8°C), blood pressure is 108/72 mmHg, pulse is 86/min, and respirations are 14/min. Of interest, the patient has not increased much in length or weight in the past 3 months. He is now in the 25th percentile for weight but is in the 90th percentile for head circumference. The patient does not appear to have any gross or fine motor deficiencies. Of note, he has coarse facial features that were not previously noted, including a long face, prominent forehead, and protruding eyes. The patient has corneal clouding bilaterally. At rest, the patient keeps his mouth hanging open. After extensive workup, the patient is found to have 2 mutated copies of the IDUA gene, with no production of the protein iduronidase. Which of the following is the likely mutation found in this disease?", "answer": "Nonsense mutation", "options": {"A": "Chromosomal translocation", "B": "Interstitial deletion", "C": "Missense mutation", "D": "Nonsense mutation", "E": "Silent mutation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old man is brought to the emergency department 20 minutes after being stabbed in the left thigh. His pulse is 110/min, respirations are 20/min, and blood pressure is 110/70 mm Hg. Examination shows a 2-cm wound overlying a pulsatile mass on the left anterior thigh, 4 cm below the inguinal crease. A thrill is palpated, and a bruit is heard over this area. Peripheral pulses are normal bilaterally. The patient is at greatest risk for which of the following?", "answer": "High-output cardiac failure", "options": {"A": "Pudendal nerve compression", "B": "High-output cardiac failure", "C": "Iliac artery aneurysm", "D": "Femoral head necrosis", "E": "Erectile dysfunction"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 69-year-old man presents to his primary care physician for pain when he walks. He states that the pain is the worst in his left great toe but is also present in his hips and knees. He says that his symptoms are worse with activity and tend to improve with rest. His symptoms have progressively worsened over the past several years. He has a past medical history of obesity, type II diabetes mellitus, smoking, and hypertension. He drinks roughly ten beers per day. His current medications include metformin, insulin, lisinopril, and hydrochlorothiazide. The patient has a recent travel history to Bangkok where he admits to having unprotected sex. On physical exam, examination of the lower extremity results in pain. There is crepitus of the patient's hip when his thigh is flexed and extended. Which of the following is the most likely diagnosis?", "answer": "Osteoarthritis", "options": {"A": "Osteoarthritis", "B": "Rheumatoid arthritis", "C": "Infectious arthritis", "D": "Gout", "E": "Pseudogout"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 51-year-old woman presents to your office with 2 weeks of fatigue and generalized weakness. She has a past medical history of diabetes, hypertension, and hyperlipidemia. She was recently diagnosed with rheumatoid arthritis and started on disease-modifying therapy. She states she has felt less able to do things she enjoys and feels guilty she can't play sports with her children. Review of systems is notable for the patient occasionally seeing a small amount of bright red blood on the toilet paper. Laboratory studies are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 7,700/mm^3 with normal differential\nPlatelet count: 207,000/mm^3\nMCV: 110 fL\n\nWhich of the following is the most likely etiology of this patient's fatigue?", "answer": "Medication side effect", "options": {"A": "Depression", "B": "Gastrointestinal bleed", "C": "Iron deficiency", "D": "Medication side effect", "E": "Vitamin B12 deficiency"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old man presents with acute-onset fever and weakness followed by shifting neurologic deficits (aphasia, motor deficits), which have lasted for a few days. His relatives add that his quantity of urine has reduced significantly over the last few days. He has never had any similar symptoms. Laboratory findings are significant for the following:\nHb 8.6 g/dL\nWBC 6.5 × 1000/mm3\nPlatelets 43 × 1000/mm3\nCr 3.1 mg/dL\nBUN 25 mg/dL\nNa+ 136 mg/dL\nK+ 4.2 mg/dL\nCl- 101 mg/dL\nHCO3- 24 mg/dL\nGlu 101 mg/dL\nExamination of the peripheral smear shows the presence of schistocytes, helmet cells, and spherocytes. \nWhich of the following is true regarding this patient's condition?", "answer": "Plasmapheresis is the treatment of choice.", "options": {"A": "The condition is caused by the deficiency of a sodium transporter.", "B": "A platelet transfusion should be given.", "C": "Bleeding time will be normal.", "D": "Splenectomy should be performed as early as possible.", "E": "Plasmapheresis is the treatment of choice."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 38-year-old man comes to the physician because of a 1-month history of fever and a cough productive of a moderate amount of yellowish sputum. He has had a 6-kg (13-lb) weight loss during this period. He emigrated from the Middle East around 2 years ago. His father died of lung cancer at the age of 54 years. He has smoked one pack of cigarettes daily for 18 years. He appears malnourished. His temperature is 38.1°C (100.6°F), pulse is 101/min, and blood pressure is 118/72 mm Hg. Crackles are heard on auscultation of the chest. Cardiac examination shows no abnormalities. The abdomen is soft and nontender. Laboratory studies show:\nHemoglobin 12.3 g/dL\nLeukocyte count 13,200/mm3\nPlatelet count 330,000/mm3\nErythrocyte sedimentation rate 66 mm/h\nSerum\nUrea nitrogen 16 mg/dL\nGlucose 122 mg/dL\nCreatinine 0.9 mg/dL\nUrinalysis is within normal limits. An x-ray of the chest is shown. Which of the following is the most appropriate next step in management?\"", "answer": "Collect sputum specimens for acid-fast bacilli smear microscopy, culture, and nucleic acid amplification", "options": {"A": "Perform a high-resolution CT scan of the chest", "B": "Start treatment with oral levofloxacin", "C": "Collect sputum specimens for acid-fast bacilli smear microscopy, culture, and nucleic acid amplification", "D": "Perform transbronchial lung biopsy of the suspected lesion", "E": "Perform an interferon-gamma release assay"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old girl is brought to the physician by her mother for a 6-week history of fatigue, fever, and recurrent epistaxis. She has a history of duodenal atresia and an atrioventricular septal defect. She is at the 5th percentile for height and 30th percentile for weight. Physical examination shows painless cervical lymphadenopathy. Her hands are short and broad and there is a space between the first and second toes bilaterally. The spleen tip is palpated 3 cm below the left costal margin. Bone marrow aspirate shows leukocytosis with 50% lymphoblasts. Which of the following best explains this patient's condition?", "answer": "Meiotic nondisjunction", "options": {"A": "Meiotic nondisjunction", "B": "Deletion of a chromosome segment", "C": "Uniparental disomy", "D": "Trinucleotide repeat expansion", "E": "Unbalanced Robertsonian translocation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman, gravida 2, para 1, at 37 weeks' gestation is admitted to the hospital in active labor. She has received routine prenatal care, but she has not been tested for group B streptococcal (GBS) colonization. Pregnancy and delivery of her first child were complicated by an infection with GBS that resulted in sepsis in the newborn. Current medications include folic acid and a multivitamin. Vital signs are within normal limits. The abdomen is nontender and contractions are felt every 4 minutes. There is clear amniotic fluid pooling in the vagina. The fetus is in a cephalic presentation. The fetal heart rate is 140/min. Which of the following is the most appropriate next step in management?", "answer": "Administer intrapartum intravenous penicillin", "options": {"A": "Reassurance", "B": "Obtain vaginal-rectal swab for GBS culture", "C": "Administer intrapartum intravenous penicillin", "D": "Obtain vaginal-rectal swab for GBS culture and nucleic acid amplification testing", "E": "Obtain vaginal-rectal swab for nucleic acid amplification testing"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old woman presents with diarrhea and a rash. She reports having some painful reddish nodules on her legs that she noticed a week ago. She also has been having loose stools associated with cramping lower abdominal pain for the past month. This is associated with an urgency to defecate, and defecation helps relieve the abdominal pain. The stool is occasionally blood-tinged and has some mucus. She feels fatigued but denies fever, weight loss, exposure to any sick people, or history of travel recently. No significant past medical history. Her family history is significant for osteoporosis in her mother, aunt, and older sister. On physical examination, the patient has generalized pallor. There are multiple erythematous tender nodules over the extensor surface of the legs bilaterally below the level of the knee. Abdominal examination reveals mild tenderness to palpation in the left lower quadrant. A DEXA scan is performed and reveals a T-score of -1.5 at the hips and spine. Laboratory findings are significant for microcytic anemia and an elevated ESR. A colonoscopy is performed and reveals patchy inflammation of the colon with rectal sparing. The lesions are present in patches with intermittent normal colonic mucosa. The patient is started on sulfasalazine and shows a good response. However, 6 months later, she returns with a recurrence of her symptoms. A repeat colonoscopy reveals more extensive involvement of the colon and the small bowel. A second drug is added to her treatment regimen. Which of the following is the most common adverse effect associated with the use of this second drug?", "answer": "Infection", "options": {"A": "Worsening of osteoporosis", "B": "Infection", "C": "Rash", "D": "Megaloblastic anemia", "E": "Hepatotoxicity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-year-old boy presents to the emergency department with several days of high fever accompanied by runny nose, cough, and red itchy eyes. Upon further history, you learn that the family is undocumented and has not had access to primary health services. Upon physical examination you see a red, slightly bumpy rash extending from the head to the mid-chest level. If you had examined this child a prior to the development of the rash, which of the following signs may you have observed?", "answer": "Koplik spots", "options": {"A": "Parotid gland swelling", "B": "Posterior auricular lymphadenopathy", "C": "Blueberry muffin rash", "D": "Dermatomal vesicular rash", "E": "Koplik spots"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 75-year-old female patient comes to the emergency department with altered mental status. She is brought in by her daughter with whom the patient lives. The patient’s daughter said they were watching TV when her mother became unresponsive. On exam the patient withdraws to pain but does not open her eyes or speak. An emergent head CT is done and shows an intracranial bleed. The patient is moved to the ICU and intubated. Further history is obtained from the daughter. The patient has a past medical history of diabetes and a previous stroke. Her medications are metformin and warfarin. The patient is compliant with all of her medications. The daughter says that the patient changed her diet about 1 month ago in response to a diet she saw on a talk show. Which of the following foods is most likely to cause the pathology seen in this patient?", "answer": "Grapefruit juice", "options": {"A": "St. John’s wort", "B": "Chili peppers", "C": "Grapefruit juice", "D": "Spinach", "E": "Green tea"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old gravida 1 para 0 woman visits an OB/GYN for her first prenatal visit and to establish care. She is concerned about the costs related to future prenatal visits, medications, procedures, and the delivery. She has no type of health insurance through her work and has previously been denied coverage by public health insurance based on her income. Since then she has been promoted and earns a higher salary. In addressing this patient, which of the following is the most appropriate counseling?", "answer": "She may be eligible for Medicaid because she is pregnant", "options": {"A": "She may be eligible for Medicaid based on her higher salary", "B": "She may be eligible for Medicaid because she is pregnant", "C": "She may be eligible for Medicare based on her higher salary", "D": "She may be eligible for Medigap based on her higher salary", "E": "She may be eligible for Medigap because she is pregnant"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 19-year-old male with cystic fibrosis is evaluated in the clinic for regular health maintenance. He is compliant with his respiratory therapy, but states that he often \"forgets\" to take the medications before he eats. A panel of labs is drawn which reveals a moderate vitamin D deficiency. Which of the following electrolyte abnormalities might be seen as a consequence of vitamin D deficiency?", "answer": "Decreased calcium and decreased phosphate", "options": {"A": "Increased calcium and increased phosphate", "B": "Increased calcium and decreased phosphate", "C": "Decreased calcium and increased phosphate", "D": "Decreased calcium and decreased phosphate", "E": "Normal calcium and decreased phosphate"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 57-year-old male presents with a primary complaint of erectile dysfunction. After proper evaluation, the patient is started on daily administration of sildenafil. This medication directly causes accumulation of which of the following intracellular mediators?", "answer": "cGMP", "options": {"A": "Ca2+", "B": "cGMP", "C": "AMP", "D": "NO", "E": "ANP"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old Caucasian female is admitted to the emergency department with a 48-hour history of severe and diffuse abdominal pain, nausea, vomiting, and constipation. Her personal history is unremarkable except for an ectopic pregnancy 5 years ago. Upon admission, she is found to have a blood pressure of 120/60 mm Hg, a pulse of 105/min, a respiratory rate 20/min, and a body temperature of 37°C (98.6°F). She has diffuse abdominal tenderness, hypoactive bowel sounds, and mild distention on examination of her abdomen. Rectal and pelvic examination findings are normal. An abdominal plain film of the patient is given. What is the most likely cause of this patient’s condition?", "answer": "Adhesions", "options": {"A": "Malrotation", "B": "Hernia", "C": "Adhesions", "D": "Enlarged Peyer’s plaques", "E": "Gastrointestinal malignancy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman presents with three-days of vaginal burning, itching, and pain with intercourse. She is in a monogamous relationship with her husband and has an intrauterine device for contraception. Her past medical history is unremarkable, except for recently being treated with antibiotics for sinusitis. Pelvic exam is remarkable for vulvar excoriations, vaginal wall edema, and thick, white discharge in the vault. Wet mount with KOH staining reveals budding filaments with pseudohyphae and hyphae. Which of the following is the most appropriate treatment?", "answer": "Fluconazole", "options": {"A": "Fluconazole", "B": "Itraconazole", "C": "Metronidazole", "D": "Posaconazole", "E": "Voriconazole"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-week-old female newborn is brought to the physician for the evaluation of red eyes with discharge for 2 days. She was born at 39 weeks' gestation to a 22-year-old woman. Pregnancy and delivery were uncomplicated. The mother received irregular prenatal care during the second half of the pregnancy. The newborn weighed 3700 g (8 lb 2.5 oz) at birth, and no congenital anomalies were noted. She currently weighs 4000 g (8 lb 13 oz). Examination of the newborn shows pink skin. The lungs are clear to auscultation. There is mucopurulent discharge in both eyes and mild eyelid swelling. Polymerase chain reaction assay of conjunctival scraping confirms the diagnosis. Which of the following is the most appropriate next step in management?", "answer": "Oral erythromycin administration", "options": {"A": "Reassurance and follow-up in 1 week", "B": "Intravenous acyclovir administration", "C": "Oral doxycycline administration", "D": "Oral erythromycin administration", "E": "Topical silver nitrate administration"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old woman was admitted to the surgical service after an uncomplicated appendectomy. She underwent surgery yesterday and had an uneventful postoperative course. However, she now complains that she is unable to completely void. She also complains of pain in the suprapubic area. You examine her and confirm the tenderness and fullness in the suprapubic region. You ask the nurse to perform a bladder scan, which reveals 450cc. What is the next appropriate step in management?", "answer": "Catheterization", "options": {"A": "Oral bethanechol chloride", "B": "Neostigmine methylsulfate injection", "C": "Intravenous neostigmine methylsulfate", "D": "Intravenous furosemide", "E": "Catheterization"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old woman presents to her family physician with a headache. The patient reports that the symptoms started about 2 hours ago when she woke up and have not improved. She states the pain is moderate, throbbing, tight in character, and is located in the occipital region bilaterally. The patient denies any visual and audio disturbances, nausea, and vomiting. She recalls 2 similar headaches in the past month. She has no other relevant medical history. Current medications are alendronate and a daily multivitamin. The patient works long hours as a corporate attorney. A review of systems is significant for mild photophobia. Her temperature is 37.0°C (98.6°F), the blood pressure is 110/70 mm Hg, the pulse is 70/min, the respiratory rate is 18/min, and the oxygen saturation is 98% on room air. On physical exam, the patient is alert and oriented. There is moderate tenderness to palpation diffusely over the upper posterior cervical muscles and occipital region of the scalp. The remainder of the physical exam is normal. Laboratory tests are normal. Urine pregnancy test is negative. What is the next best step in management?", "answer": "Recommend lifestyle changes, relaxation techniques, and massage therapy", "options": {"A": "Non-contrast CT of the head and neck", "B": "T1/T2 MRI of the head and neck", "C": "Temporal artery biopsy", "D": "Administer high-flow oxygen, ibuprofen 200 mg orally, and sumatriptan 6 mg subcutaneously", "E": "Recommend lifestyle changes, relaxation techniques, and massage therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old man comes to the physician for a follow-up examination. Paroxetine therapy was initiated 6 weeks ago for a major depressive episode. He now feels much better and says he is delighted with his newfound energy. He gets around 8 hours of sleep nightly. His appetite has increased. Last year, he had two episodes of depressed mood, insomnia, and low energy during which he had interrupted his job training and stopped going to the gym. Now, he has been able to resume his job at a local bank. He also goes to the gym three times a week to work out and enjoys reading books again. His temperature is 36.5°C (97.7°F), pulse is 70/min, and blood pressure is 128/66 mm Hg. Physical and neurologic examinations show no abnormalities. On mental status examination, he describes his mood as \"\"good.” Which of the following is the most appropriate next step in management?\"", "answer": "Continue paroxetine therapy for 2 years", "options": {"A": "Continue paroxetine therapy for 2 years", "B": "Switch from paroxetine to venlafaxine therapy", "C": "Discontinue paroxetine", "D": "Continue paroxetine therapy for 6 months", "E": "Switch from paroxetine to lithium therapy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-year-old girl comes to the physician because of a 2-year history of irregular menstrual bleeding. Menses have occurred at irregular 45- to 60-day intervals since menarche at the age of 13 years. Her last menstrual period was 5 weeks ago and lasted for 7 days with heavy flow and no cramping. She is not sexually active. She is 171 cm (5 ft 7 in) tall and weighs 58 kg (128 lb); BMI is 20 kg/m2. Her temperature is 36.6°C (97.8°F), pulse is 80/min, and blood pressure is 110/60 mm Hg. Pelvic examination shows a normal-appearing vagina and cervix. Bimanual examination shows a normal-sized uterus and no palpable adnexal masses. The remainder of the physical examination shows no abnormalities. A urine pregnancy test is negative. Which of the following is the most likely explanation for this patient's symptoms?", "answer": "Anovulation", "options": {"A": "Pituitary adenoma", "B": "Endometriosis", "C": "Polycystic ovary syndrome", "D": "Anovulation", "E": "Ovarian insufficiency\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought by his parents to his pediatrician due to progressive fatigue and shortness of breath while playing sports. He is otherwise healthy with no known medical disorders and no other symptoms. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. On physical examination, his temperature is 36.9ºC (98.4ºF), pulse rate is 90/min, blood pressure is 100/70 mm Hg, and respiratory rate is 18/min. Pulses in all four extremities are equal and normally palpated; there is no radio-femoral delay. The pediatrician suspects a congenital heart disease after auscultation of the heart. Which of the following congenital heart diseases is most likely to present with the clinical features listed above?", "answer": "Atrial septal defect", "options": {"A": "Aortopulmonary window defect", "B": "Coarctation of the aorta", "C": "Complete atrioventricular septal defect", "D": "Atrial septal defect", "E": "Double-outlet right ventricle with subaortic ventricular septal defect"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 17-year-old boy is brought to the emergency department by his mother for further evaluation after elective removal of his wisdom teeth. During the procedure, the patient had persistent bleeding from the teeth's surrounding gums. Multiple gauze packs were applied with minimal effect. The patient has a history of easy bruising. The mother says her brother had similar problems when his wisdom teeth were removed, and that he also has a history of easy bruising and joint swelling. The patient takes no medications. His temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 108/74 mm Hg. Laboratory studies show:\nHematocrit 35%\nLeukocyte count 8,500/mm3\nPlatelet count 160,000/mm3\nProthrombin time 15 sec\nPartial thromboplastin time 60 sec\nBleeding time 6 min\nFibrin split products negative\nSerum\nUrea nitrogen 20 mg/dL\nCreatinine 1.0 mg/dL\nBilirubin\nTotal 1.0 mg/dL\nDirect 0.5 mg/dL\nLactate dehydrogenase 90 U/L\nPeripheral blood smear shows normal-sized platelets. Which of the following is the most likely diagnosis?\"", "answer": "Hemophilia", "options": {"A": "Von Willebrand disease", "B": "Glanzmann thrombasthenia", "C": "Immune thrombocytopenia", "D": "Hemophilia", "E": "Bernard-Soulier syndrome"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old man with a history of diabetes mellitus presents to his primary care physician with lethargy, joint pain, and impotence. Lab evaluation is notable for a ferritin of 1400 ug/L (nl <300 ug/L), increased total iron, increased transferrin saturation, and decreased total iron binding capacity. All of the following are true regarding this patient's condition EXCEPT:", "answer": "It may improve with calcium chelators", "options": {"A": "It may lead to a decline in cardiac function", "B": "It may improve with serial phlebotomy", "C": "It may improve with calcium chelators", "D": "It is associated with an increased risk for hepatocellular carcinoma", "E": "It results in skin bronzing"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old man is brought to the clinic by his daughter who has noticed behavioral changes and frequent headaches for the past 2 weeks. The patient’s daughter says he has been having memory and simple calculation issues, gets upset easily, and his grip strength has dramatically declined. The patient was completely normal prior to these recent changes and used to be able to perform his activities of daily living without a problem. He has a past medical history significant for hypertension, stable angina, and benign prostatic hypertrophy, as well as frequent falls with the last one occurring 1 month ago. Physical examination is remarkable for dyscalculia, short-term memory deficits, and decreased grip strength (4/5) in his right hand. A noncontrast CT of the head is performed and is shown in the image. Which of the following is the most likely etiology of this patient condition?", "answer": "Tearing of bridging veins", "options": {"A": "Arteriovenous malformation", "B": "Tearing of bridging veins", "C": "Tearing of the middle meningeal artery", "D": "Dural arteriovenous fistula", "E": "Charcot-Bouchard aneurysm"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old woman, gravida 1, para 0, at 40 weeks' gestation is admitted to the hospital in active labor. Pregnancy was complicated by iron deficiency anemia treated with iron supplements. At the beginning of the first stage of labor, there are coordinated, regular, rhythmic contractions of high intensity that occur approximately every 10 minutes. Four hours later, the cervix is 100% effaced and 10 cm dilated; the vertex is at -1 station. Over the next two hours, there is minimal change in in fetal descent; vertex is still at -1 station. Fetal birth weight is estimated at the 75th percentile. The fetal heart rate is 145/min and is reactive with no decelerations. Contractions occurs approximately every 2 minutes with adequate pressure. Epidural anesthesia was not given, as the patient is coping well with pain. Which of the following is the most appropriate next step in management?", "answer": "Observation for another hour", "options": {"A": "Administration of terbutaline", "B": "Cesarean section", "C": "Vacuum-assisted delivery", "D": "Observation for another hour", "E": "Epidural anesthesia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old woman, gravida 2, para 1, at 26 weeks gestation comes to the physician for a routine prenatal visit. Physical examination shows a uterus consistent in size with a 26-week gestation. Fetal ultrasonography shows a male fetus with a thick band constricting the right lower arm; the limb distal to the constrictive band cannot be visualized. The most likely condition is an example of which of the following embryological abnormalities?", "answer": "Disruption", "options": {"A": "Deformation", "B": "Agenesis", "C": "Disruption", "D": "Malformation", "E": "Aplasia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old man presents to the emergency department due to a rash. He states the rash started last night and is very concerning to him. The patient cannot remember being exposed to any environmental stimuli such as new detergents or poison ivy. The patient recently started following with a primary care provider who is helping him manage his arthritis and a new onset cough. His temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 125/min, respirations are 18/min, and oxygen saturation is 98% on room air. Physical exam is notable for the findings of coalescing erythematous macules, bullae, desquamation, and mucositis only on the upper half of his back. Cardiopulmonary exam and abdominal exam are within normal limits. Inspection of the patient’s oropharynx reveals ulcers and erythema. Which of the following is the most likely diagnosis?", "answer": "Steven-Johnson syndrome", "options": {"A": "Erythema multiforme", "B": "Herpes simplex virus", "C": "Herpes zoster", "D": "Steven-Johnson syndrome", "E": "Toxic epidermal necrolysis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 12-year-old boy presents to the pediatrician with complaints of chronic cough for the past two years. The cough is present during the day, especially after returning from school. His school teacher says he does not cough at school. The cough is absent while he is asleep, although it increases during examinations or when he experiences boredom. His mother reports that there was a one-month period where he did not cough, but during that month, he used to shrug his shoulders frequently, especially when he was stressed or fatigued. There is no history of sneezing, nasal discharge, nasal congestion, headache, ear symptoms, or breathing difficulty. Detailed history does not suggest the presence of a mood disorder, obsessive-compulsive symptoms, or attention-deficit/hyperactivity disorder. There is no past history of a known neurological disorder, and there is no history of substance abuse. On physical examination, his vital signs are stable. Examination of his respiratory and cardiovascular systems is normal. However, the pediatrician notes repeated eye blinking; upon asking about eye blinking, the mother reports that he has had this habit since he was almost eight years old. Further inquiry suggests that eye blinking, coughing, and grunting disappear for a few weeks without explanation, only to reappear again. Which of the following drugs is likely to be most effective to control this patient’s symptoms?", "answer": "Haloperidol", "options": {"A": "Atomoxetine", "B": "Clonidine", "C": "Fluoxetine", "D": "Haloperidol", "E": "Levetiracetam"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old woman consults an obstetrician as she is planning to become pregnant. She has been diagnosed with HIV (human immunodeficiency virus) infection recently and is currently taking antiretroviral therapy (HAART), as prescribed by her physician. The obstetrician emphasizes the importance of antenatal and peripartum antiretroviral therapy for reducing the risk of mother-to-child transmission of HIV. She also tells the patient that certain antiretroviral drugs, if taken during pregnancy, increase the risk of birth defects in the fetus. She gives a printed list of such drugs to the woman for educational and informational purposes. Which of the following drugs are most likely to be present on the list?", "answer": "Efavirenz and Delavirdine", "options": {"A": "Abacavir and Didanosine", "B": "Efavirenz and Delavirdine", "C": "Lamivudine and Nevirapine", "D": "Lopinavir and Ritonavir", "E": "Nelfinavir and Saquinavir"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 1-month-old baby is brought to the emergency department because he had a coughing spell while feeding and turned blue. The mother says that the blue color went away when she picked the baby up and brought his knees to his chest. The physician orders a chest X-ray which shows a boot-shaped heart and he tells the mother that the baby has a condition that is caused by an anterosuperior displacement of the infundibular septum. What are the 4 features of the baby’s cardiac condition?", "answer": "Pulmonary stenosis, right ventricular hypertrophy, ventricular septal defect, overriding aorta", "options": {"A": "Pulmonary stenosis, left ventricular hypertrophy, ventricular septal defect, overriding aorta", "B": "Pulmonary regurgitation, left ventricular hypertrophy, ventricular septal defect, overriding aorta", "C": "Pulmonary regurgitation, right ventricular hypertrophy, atrial septal defect, overriding aorta", "D": "Pulmonary stenosis, right ventricular hypertrophy, atrial septal defect, overriding pulmonary artery", "E": "Pulmonary stenosis, right ventricular hypertrophy, ventricular septal defect, overriding aorta"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old girl is brought to the physician by her mother because she has not had her menstrual period yet. At birth, she was found to have partial labial fusion and clitoromegaly. The mother reports that during the pregnancy she had noticed abnormal hair growth on her chin. The girl has severe acne. Three years ago, she broke her wrist after a minor trauma. Last year, she sustained a spinal compression fracture after lifting a box during a move. She currently takes oral isotretinoin and an oral contraceptive. The patient is at the 97th percentile for height and 50th percentile for weight. Physical examination shows numerous inflamed pustules on her face and upper back. Breast development is at Tanner stage I. The patient refuses to have a pelvic examination. A pelvic ultrasound shows ovaries with multiple cysts and a normal uterus. Which of the following is the most likely diagnosis?", "answer": "Aromatase deficiency", "options": {"A": "Polycystic ovary syndrome", "B": "Congenital adrenal hyperplasia", "C": "Hyperprolactinemia", "D": "Turner syndrome", "E": "Aromatase deficiency"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-month-old infant is brought to the physician’s office by his parents due to a fever, cough, and shortness of breath. The cough is dry and has been progressively worsening for the past 48 hours along with the shortness of breath. His fever never exceeded 37.8°C (100.0°F) at home. The parents say that he has also had abundant nasal drainage and loss of appetite. He is irritable and vomited twice during this period. He has no relevant medical or family history.\nHis vitals are the following:\nPulse rate 165/min\nRespiratory rate 77/min\nTemperature 38.0°C (100.4°F)\nOn physical examination, there is nasal congestion with thick secretions, accompanied by nasal flaring. On chest examination, intercostal retractions are seen and diffuse wheezing on both sides are heard on auscultation. What is the most likely cause?", "answer": "Bronchiolitis", "options": {"A": "Asthma", "B": "Sinusitis", "C": "Rhinopharyngitis", "D": "Bronchiolitis", "E": "Laryngotracheitis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old woman comes to the physician because of fever, chills, myalgias, and joint pain 1 month after undergoing aortic prosthetic valve replacement due to high-grade aortic stenosis. She does not drink alcohol or use illicit drugs. Her temperature is 39.3°C (102.8°F). She appears weak and lethargic. Physical examination shows crackles at both lung bases and a grade 2/6, blowing diastolic murmur over the right sternal border. Laboratory studies show leukocytosis and an elevated erythrocyte sedimentation rate. The causal organism is most likely to have which of the following characteristics?", "answer": "Novobiocin-sensitive, coagulase-negative cocci", "options": {"A": "Alpha hemolytic, optochin-sensitive diplococci", "B": "Novobiocin-sensitive, coagulase-negative cocci", "C": "Catalase-negative cocci that grows in 6.5% saline", "D": "Beta hemolytic, bacitracin-sensitive cocci", "E": "Alpha hemolytic, optochin-resistant cocci"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old woman presents to her primary care provider with vision loss. She reports that twice over the last 2 weeks she has had sudden “black out” of the vision in her right eye. She notes that both episodes were painless and self-resolved over approximately a minute. The patient’s past medical history is significant for hypertension, diet-controlled diabetes mellitus, and hypothyroidism. Her family history is notable for coronary artery disease in the patient’s father and multiple sclerosis in her mother. Ophthalmologic and neurologic exam is unremarkable. Which of the following is the best next step in management?", "answer": "Ultrasound of the carotid arteries", "options": {"A": "Check serum inflammatory markers", "B": "Emergent referral to ophthalmology", "C": "Intravenous dexamethasone", "D": "MRI of the brain", "E": "Ultrasound of the carotid arteries"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 37-year-old man presents to his primary care provider with dysphagia. He notes that his symptoms began several weeks ago and have worsened over time. He now has trouble swallowing solids and liquids. He denies any other symptoms. He has no significant past medical history. Travel history reveals a recent trip to South America but no other travel outside the United States. His temperature is 100°F (37.8°C), blood pressure is 120/81 mmHg, pulse is 99/min, respirations are 14/min, and oxygen saturation is 98% on room air. HEENT exam is unremarkable. He has no palpable masses in his abdomen. What is the most appropriate next step in management?", "answer": "Barium swallow", "options": {"A": "Barium swallow", "B": "Endoscopy", "C": "Manometry", "D": "Myotomy", "E": "Nifurtimox"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 61-year-old woman presents for a routine health visit. She complains of generalized fatigue and lethargy on most days of the week for the past 4 months. She has no significant past medical history and is not taking any medications. She denies any history of smoking or recreational drug use but states that she drinks “socially” approx. 6 nights a week. She says she also enjoys a “nightcap,” which is 1–2 glasses of wine before bed every night. The patient is afebrile, and her vital signs are within normal limits. On physical examination, there is significant pallor of the mucous membranes. Laboratory findings are significant for a mean corpuscular volume (MCV) of 72 fL, leukocyte count of 4,800/mL, hemoglobin of 11.0 g/dL, and platelet count of 611,000/mL. She is started on oral ferrous sulfate supplements. On follow-up, her laboratory parameters show no interval change in her MCV or platelet level. Which of the following is the best next step in the management of this patient?", "answer": "Continue oral ferrous sulfate and supplement with ascorbic acid", "options": {"A": "Transfuse the patient with whole blood", "B": "Continue oral ferrous sulfate and supplement with ascorbic acid", "C": "Continue oral ferrous sulfate and supplement with omeprazole", "D": "Administer folate", "E": "Administer iron intravenously"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 41-year-old man with HIV comes to the physician because of rectal bleeding and itching for 2 weeks. During this period, he has also had pain with defecation. Four months ago, he was diagnosed with anogenital warts that were treated with cryotherapy. Over the past year, he has been sexually active with 3 male partners. He uses condoms inconsistently. Current medications are zidovudine, emtricitabine, and efavirenz. Digital rectal examination and anoscopy show an exophytic mass on the anal margin that is protruding into the anal canal. The mass is tender to palpation and bleeds easily on contact. Laboratory studies show a leukocyte count of 7,600/mm3 and a CD4+ T-lymphocyte count of 410/mm3 (N ≥ 500). A biopsy specimen of the lesion shows a well-differentiated squamous cell carcinoma. Which of the following cellular processes was most likely involved in the pathogenesis of this patient's malignancy?", "answer": "Inactivation of TP53 gene\n\"", "options": {"A": "Activation of c-myc gene", "B": "Inactivation of VHL gene", "C": "Activation of TAX gene", "D": "Inactivation of WT1 gene", "E": "Inactivation of TP53 gene\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old child is brought to the emergency department by his parents. The child presents with significant rapid breathing and appears unwell. On examination, his liver size is 1.5 times larger than children of his age, and he has mild pitting edema in his legs. This child is also in the lower weight-age and height-age percentiles. On auscultation, mild rales were noted and a fixed split S2 was heard on inspiration. There is no family history of congenital disorders or metabolic syndromes. Which of the following is the likely diagnosis?", "answer": "Atrial septal defect", "options": {"A": "Liver failure", "B": "Atrial septal defect", "C": "Patent foramen ovale", "D": "Endocardial cushion syndrome", "E": "Transposition of the great vessels"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A neurophysiologist describes the mechanism of a specific type of synaptic transmission to his students. While illustrating this, he points out that when the action potential reaches the presynaptic terminal of a chemical synapse, the voltage-gated Ca2+ channels open. Ca2+ ions trigger the release of neurotransmitters from vesicles in the presynaptic terminal. In this type of synaptic transmission, increased cytosolic Ca2+ levels cause the release of a neurotransmitter from small vesicles with dense cores. Which of the following neurotransmitters is most likely to be the one that is released into the synaptic cleft in this type of synapse?", "answer": "Epinephrine", "options": {"A": "Follicle stimulating hormone", "B": "Epinephrine", "C": "Glycine", "D": "GABA (γ-amino butyric acid)", "E": "Glutamate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old man with a history of major depressive disorder is brought to the emergency department by his wife because of a sudden onset of restlessness and disorientation that developed 3 hours ago. The patient’s wife says that he suddenly started sweating, having tremors, and mumbling to himself. Yesterday, the patient visited his psychiatrist with worsening depression who added phenelzine to his current treatment regimen.  No other significant past medical history. His temperature is 39.7°C (103.5°F), blood pressure is 145/90 mm Hg, and pulse is 115/min. On physical examination, the skin is flushed. Mucous membranes are dry, and pupils are dilated. There is pronounced clonus in the extremities bilaterally. Babinski sign is present bilaterally. All the patient’s medications are discontinued, and intravenous fluids are started. Which of the following drugs most likely interacted with phenelzine to cause this patient’s condition?", "answer": "Sertraline", "options": {"A": "Mirtazapine", "B": "Bupropion", "C": "Sertraline", "D": "Olanzapine", "E": "Lithium"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old woman comes to your office because she noticed the growth of unwanted hair on her upper lip, chin, and chest. She has also noticed an increase in blackheads and pimples on her skin. Her female partner has also recently brought to her attention the deepening of her voice, weight gain, and changes in her external genitalia that generated some personal relationship issues. The patient is frustrated as these changes have appeared over the course of the last 8 months. She claims that she was feeling completely normal before all of these physical changes started. Physical examination shows dark coarse stubbles distributed along her upper lip, chin, chest, back, oily skin, and moderately inflamed acne. Pelvic examination reveals a clitoris measuring 12 mm long, a normal sized mobile retroverted uterus, and a firm, enlarged left ovary. What is the most likely diagnosis of this patient?", "answer": "Sertoli-Leydig cell tumour", "options": {"A": "Thecoma", "B": "Sertoli-Leydig cell tumour", "C": "Adrenocortical carcinoma", "D": "Granulosa cell tumour", "E": "Polycystic ovarian syndrome (PCOS)"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 44-year-old female presents to her primary care physician with complaints of headache, fatigue, muscle weakness, and frequent urination. These issues have developed and worsened over the past month. She has no significant prior medical or surgical history other than cholecystitis managed with cholecystectomy 5 years ago. Her vital signs at today's visit are as follows: T 37.1 C, HR 77, BP 158/98, RR 12, and SpO2 99%. Physical examination is significant for tetany, mild abdominal distension, reduced bowel sounds, and hypertensive retinal changes on fundoscopic exam. The physician orders a laboratory and imaging work-up based on his suspected diagnosis. An abdominal CT scan shows an 8 cm unilateral left adrenal mass suggestive of an adrenal adenoma. Which of the following sets of laboratory findings would be most likely in this patient?", "answer": "Metabolic alkalosis, hypernatremia, hypokalemia", "options": {"A": "Metabolic acidosis, hypernatremia, hyperkalemia", "B": "Metabolic acidosis, hyponatremia, hyperkalemia", "C": "Metabolic acidosis, hypernatremia, hypokalemia", "D": "Metabolic alkalosis, hypernatremia, hyperkalemia", "E": "Metabolic alkalosis, hypernatremia, hypokalemia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 58-year-old woman comes to the physician because of a 6-month history of difficulty walking, clumsiness of her arms and legs, and slurred speech. Physical examination shows masked facies and a slow, shuffling gait. When her ankles are passively flexed, there is involuntary, jerky resistance. Treatment is initiated with a combination of levodopa and carbidopa. The addition of carbidopa is most likely to decrease the risk of which of the following potential adverse drug effects?", "answer": "Orthostatic hypotension", "options": {"A": "Resting tremor", "B": "Orthostatic hypotension", "C": "Urinary retention", "D": "Visual hallucinations", "E": "Dyskinesia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-month-old boy is brought to the pediatrician for a routine examination. Past medical history is significant for a pyloric myomectomy at 2 months of age after a few episodes of projectile vomiting. He has reached all appropriate developmental milestones. He currently lives with his parents and pet cat in a house built in the 1990s. He was weaned off of breast milk at 6 months of age. He is a very picky eater, but drinks 5–6 glasses of whole milk a day. The patient's height and weight are in the 50th percentile for his age and sex. The vital signs are within normal limits except for the presence of slight tachycardia. Physical examination reveals an alert infant with a slight pallor. Abdomen is soft and nondistended. A grade 2/6 systolic ejection murmur is noted in the left upper sternal border. Which of the following will most likely be expected in this patient's laboratory results?", "answer": "Decreased hemoglobin", "options": {"A": "Decreased vitamin B12 levels", "B": "Increased lead levels", "C": "Increased Hb S levels", "D": "Decreased hemoglobin", "E": "Metabolic alkalosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 47-year-old woman presents to a local medical shelter while on a mission trip with her church to help rebuild homes after a hurricane. She has been experiencing severe nausea, vomiting, and diarrhea for the last 2 days and was feeling too fatigued to walk this morning. On presentation, her temperature is 99.2°F (37.3°C), blood pressure is 95/62 mmHg, pulse is 121/min, and respirations are 17/min. Physical exam reveals decreased skin turgor, and a stool sample reveals off-white watery stools. Gram stain reveals a gram-negative, comma-shaped organism that produces a toxin. Which of the following is consistent with the action of the toxin most likely involved in the development of this patient's symptoms?", "answer": "Increased adenylyl cyclase activity", "options": {"A": "Activation of receptor tyrosine kinase", "B": "Cleavage of junctional proteins", "C": "Decreased ribosomal activity", "D": "Increased adenylyl cyclase activity", "E": "Increased membrane permeability"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old woman with alpha-1-antitrypsin deficiency undergoes a lung transplant. She tolerates the surgery well, but 3 years later develops inflammation and fibrosis in her terminal bronchioles. Which of the following best describes the pathophysiology of this patient's deterioration?", "answer": "Lymphocytic inflammation of the bronchiolar wall", "options": {"A": "Staphylocuccus aureus pneumonia", "B": "Cytotoxic T lymphocytes reacting against foreign MHCs", "C": "Lymphocytic inflammation of the bronchiolar wall", "D": "T-cell mediated vascular damage", "E": "Proliferation of grafted immunocompetent T cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 8-month-old girl is brought to her pediatrician because her mom is concerned that she may have a \"lazy eye\". She was born prematurely at 33 weeks and was 3 pounds at birth. Her mother also says that there is a history of visual problems that run in the family, which is why she wanted to make sure that her daughter was evaluated early. On presentation, she is found to have eyes that are misaligned both horizontally and vertically. Physical examination and labs reveal no underlying disorders, and the patient is discharged with occlusion therapy to help correct the misalignment. Which of the following would most likely have also been seen on physical exam?", "answer": "Asymmetric corneal light reflex", "options": {"A": "Asymmetric corneal light reflex", "B": "Bitemporal hemianopsia", "C": "Increased intraocular pressure", "D": "Fundus neovascularization", "E": "Nystagmus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 13-year-old teenage girl was brought to the emergency department by her mom after she collapsed. Her mom reports that she was at a birthday party when all of a sudden she fell. She reported left foot weakness and has been limping ever since. The patient has been healthy and had an uncomplicated birth history, though her mom reports that she just recovered from a cold. She currently lives with her younger sister and mother as her parents recently divorced. She does well in school and has a handful of good friends. Her physical exam demonstrated normal bulk and tone, 5/5 strength in all motions, 2+ and symmetric reflexes at biceps, triceps and knees. She had 1+ ankle reflex on left. What is the most likely explanation for her symptoms?", "answer": "Conversion disorder", "options": {"A": "Cerebral vascular accident", "B": "Conversion disorder", "C": "Guillain-Barre syndrome", "D": "Multiple sclerosis", "E": "Myasthenia gravis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old woman presents to her family doctor requesting sleeping pills. She is a graduate student and confesses that she is a “worry-a-holic,” which has been getting worse for the last 6 months as the due date for her final paper is approaching. During this time, she feels more on edge, irritable, and is having difficulty sleeping. She has already tried employing good sleep hygiene practices, including a switch to non-caffeinated coffee. Her past medical history is significant for depression in the past that was managed medically. No current medications. The patient’s family history is significant for her mother who has a panic disorder. Her vital signs are within normal limits. Physical examination reveals a mildly anxious patient but is otherwise normal. Which of the following is the most effective treatment for this patient’s condition?", "answer": "Buspirone", "options": {"A": "Buspirone", "B": "Bupropion", "C": "Desensitization therapy", "D": "Relaxation training", "E": "Diazepam"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old woman presents to the emergency department with nausea and vomiting. She denies any recent illnesses, sick contacts, or consumption of foods outside of her usual diet. She reports smoking marijuana at least three times a day. Her temperature is 97.7°F (36.5°C), blood pressure is 90/74 mmHg, pulse is 100/min, respirations are 10/min, and SpO2 is 94% on room air. Her conjunctiva are injected. Her basic metabolic panel is obtained below.\n\nSerum:\nNa+: 132 mEq/L\nCl-: 89 mEq/L\nK+: 2.9 mEq/L\nHCO3-: 30 mEq/L\nBUN: 35 mg/dL\nGlucose: 80 mg/dL\nCreatinine: 1.5 mg/dL\nMagnesium: 2.0 mEq/L\n\nShe continues to have multiple bouts of emesis and dry retching. What is the next best step in management?", "answer": "Administer ondansetron and isotonic saline with potassium", "options": {"A": "Obtain an urine toxin screen", "B": "Administer ondansetron per oral and provide oral rehydration solution", "C": "Administer ondansetron and isotonic saline with potassium", "D": "Administer metoclopramide and 1/2 normal saline with potassium", "E": "Administer ondansetron and 1/2 normal saline with dextrose"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old male is brought to the emergency department by fire and rescue following a motor vehicle accident in which the patient was an unrestrained driver. The paramedics report that the patient was struck from behind by a drunk driver. He was mentating well at the scene but complained of pain in his abdomen. The patient has no known past medical history. In the trauma bay, his temperature is 98.9°F (37.2°C), blood pressure is 86/51 mmHg, pulse is 138/min, and respirations are 18/min. The patient is somnolent but arousable to voice and pain. His lungs are clear to auscultation bilaterally. He is diffusely tender to palpation on abdominal exam with bruising over the left upper abdomen. His distal pulses are thready, and capillary refill is delayed bilaterally. Two large-bore peripheral intravenous lines are placed to bolus him with intravenous 0.9% saline. Chest radiograph shows multiple left lower rib fractures.\n\nWhich of the following parameters is most likely to be seen in this patient?", "answer": "Decreased pulmonary capillary wedge pressure", "options": {"A": "Decreased systemic vascular resistance", "B": "Decreased pulmonary capillary wedge pressure", "C": "Increased mixed venous oxygen saturation", "D": "Increased cardiac output", "E": "Increased right atrial pressure"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old Caucasian G1 presents at 35 weeks gestation with mild vaginal bleeding. She reports no abdominal pain or uterine contractions. She received no prenatal care after 20 weeks gestation because she was traveling. Prior to the current pregnancy, she used oral contraception. At 22 years of age she underwent a cervical polypectomy. She has a 5 pack-year smoking history. The blood pressure is 115/70 mmHg, the heart rate is 88/min, the respiratory rate is 14/min, and the temperature is 36.7℃ (98℉). Abdominal palpation reveals no uterine tenderness or contractions. The fundus is palpable between the umbilicus and the xiphoid process. An ultrasound exam shows placental extension over the internal cervical os. Which of the following factors present in this patient is the risk factor for her condition?", "answer": "Smoking", "options": {"A": "Intake of oral contraceptives", "B": "History of cervical polyp", "C": "Nulliparity", "D": "Smoking", "E": "White race"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old girl is brought to the physician by her father because of a dry cough, nasal congestion, and intermittent wheezing during the past 2 months. Since birth, she has had four upper respiratory tract infections that resolved without treatment and one episode of acute otitis media treated with antibiotics. She has a history of eczema. Her temperature is 37.1°C (98.7°F), and respirations are 28/min. Physical examination shows a shallow breathing pattern and scattered expiratory wheezing throughout both lung fields. Which of the following is the most appropriate next step in diagnosing this patient’s condition?", "answer": "Spirometry", "options": {"A": "Methacholine challenge test", "B": "Arterial blood gas analysis", "C": "Chest x-ray", "D": "Serum IgE levels", "E": "Spirometry"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old man comes to the physician for 1 month of worsening right knee pain. He has not had any trauma other than stubbing his toe 3 days ago at the garage where he works as a mechanic. Examination of the right knee shows swelling and erythema with fluctuance over the inferior patella. There is tenderness on palpation of the patella but no joint line tenderness or warmth. The range of flexion is limited because of the pain. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Inflammation of periarticular fluid-filled sac", "options": {"A": "Inflammation of the patellar tendon", "B": "Noninflammatory degeneration of the joint", "C": "Infection of the joint", "D": "Deposition of crystals in the joint", "E": "Inflammation of periarticular fluid-filled sac"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old man presents to his primary care physician with a bilateral tremor of the hands. He is a senior in high school and during the year, his grades have plummeted to the point that he is failing. He says his memory is now poor, and he has trouble focusing on tasks. His behavior has changed in the past 6 months, in that he has frequent episodes of depression, separated by episodes of bizarre behavior, including excessive alcohol drinking and shoplifting. His parents have started to suspect that he is using street drugs, which he denies. His handwriting has become very sloppy. His parents have noted slight slurring of his speech. Family history is irrelevant. Physical examination reveals upper extremity tremors, mild dystonia of the upper extremities, and mild incoordination involving his hands. The patient’s eye is shown. Which of the following best represents the etiology of this patient illness?", "answer": "Mineral accumulation in the basal ganglia", "options": {"A": "Mineral accumulation in the basal ganglia", "B": "Central nervous system demyelination", "C": "Loss of dopaminergic neurons in the nigrostriatal pathway", "D": "Autosomal dominant, trinucleotide repeat disorder", "E": "Autoimmune process following infection with group A streptococci"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-year-old boy presents to the emergency department with a 1 hour history of severe knee pain after he bumped his knee against a door. He has no past medical history though his parents say that he seems to bruise fairly easily. His parents say that they are afraid he may have accidentally taken his grandfather's warfarin medication. On presentation, he is found to have an erythematous, warm, swollen knee. Based on this presentation, a panel of laboratory tests are ordered with the following results:\n\nBleeding time: 3 minutes\nProthrombin time (PT): 12 seconds\nPartial thromboplastin time (PTT): 56 seconds\nMixing studies show no change in the above lab values\n\nWhich of the following is most likely the cause of this patient's symptoms?", "answer": "Production of an autoantibody", "options": {"A": "Deficiency in a coagulation factor", "B": "Deficiency of von Willebrand factor", "C": "Platelet defect", "D": "Production of an autoantibody", "E": "Warfarin toxicity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old man comes to the physician for a follow-up examination. He feels well. He has no urinary urgency, increased frequency, dysuria, or gross hematuria. He has a history of recurrent urinary tract infections. His last urinary tract infection was 3 months ago and was treated with ciprofloxacin. Current medications include a multivitamin. He has smoked one pack of cigarettes daily for 18 years. Vital signs are within normal limits. The abdomen is soft and nontender. There is no costovertebral angle tenderness. Laboratory studies show:\nHemoglobin 11.2 g/dL\nLeukocyte count 9,500/mm3\nPlatelet count 170,000/mm3\nSerum\nNa+ 135 mEq/L\nK+ 4.9 mEq/L\nCl- 101 mEq/L\nUrea nitrogen 18 mg/dL\nCreatinine 0.6 mg/dL\nUrine\nBlood 2+\nProtein negative\nRBC 5–7/hpf, normal shape and size\nRBC casts negative\nWBC 0–2/hpf\nBacteria negative\nUrine cultures are negative. Urine analysis is repeated and shows similar results. A cystoscopy shows no abnormalities. Which of the following is the most appropriate next step in management?\"", "answer": "CT urography\n\"", "options": {"A": "Annual urinalysis", "B": "Transrectal ultrasound", "C": "Voided urine cytology", "D": "Reassurance", "E": "CT urography\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old man presents with severe fatigue, dyspnea on exertion, and weight loss. He reports a weight loss of 15 kg (33.0 lb) over the past 3 months and feels full almost immediately after starting to eat, often feeling nauseous and occasionally vomiting. Past medical history is not significant. However, the patient reports a 10-pack-year smoking history. His temperature is 37.0°C (98.6°F), respiratory rate is 15/min, pulse is 67/min, and blood pressure is 122/98 mm Hg. Physical examination reveals paleness and conjunctival pallor. Abdominal examination reveals an ill-defined nontender mass in the epigastric region along with significant hepatomegaly. Routine laboratory studies show a hemoglobin level of 7.2 g/dL. A contrast CT scan of the abdomen is presented below. Which of the following structures is most helpful in the anatomical classification of gastrointestinal bleeding in this patient?", "answer": "Ligament of Treitz", "options": {"A": "Ligament of Treitz", "B": "Hepatoduodenal ligament", "C": "Ampulla of Vater", "D": "Sphincter of Oddi", "E": "Portal vein"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old man with a history of alcohol abuse and cirrhosis presents to the emergency department with profuse vomiting. The patient is aggressive, combative, emotionally labile, and has to be chemically restrained. The patient continues to vomit and blood is noted in the vomitus. His temperature is 99.2°F (37.3°C), blood pressure is 139/88 mmHg, pulse is 106/min, respirations are 17/min, and oxygen saturation is 100% on room air. The patient complains of sudden onset chest pain during his physical exam. A crunching and rasping sound is heard while auscultating the heart. Which of the following is the pathophysiology of the most likely diagnosis?", "answer": "Transmural tear", "options": {"A": "Dilated and tortuous veins", "B": "Inflammation of the pericardium", "C": "Mucosal tear", "D": "Pericardial fluid accumulation", "E": "Transmural tear"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 74-year-old male is brought to the emergency department 1 hour after he fell from the top of the staircase at home. He reports pain in his neck as well as weakness of his upper extremities. He is alert and immobilized in a cervical collar. He has hypertension treated with hydrochlorthiazide. His pulse is 90/min and regular, respirations are 18/min, and blood pressure is 140/70 mmHg. Examination shows bruising and midline cervical tenderness. Neurologic examination shows diminished strength and sensation to pain and temperature in the upper extremities, particularly in the hands. Upper extremity deep tendon reflexes are absent. Strength, sensation, and reflexes in the lower extremities are intact. Anal sensation and tone are present. Babinski's sign is absent bilaterally. Which of the following is most likely to confirm the cause of this patient's neurologic examination findings?", "answer": "MRI of the cervical spine without contrast", "options": {"A": "CT angiography of the neck", "B": "CT of the cervical spine with contrast", "C": "Cervical myelography", "D": "X-ray of the cervical spine", "E": "MRI of the cervical spine without contrast"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 36-year old pregnant woman (gravida 4, para 1) presents at week 11 of pregnancy. Currently, she has no complaints. She had an uncomplicated 1st pregnancy that ended in an uncomplicated vaginal delivery at the age of 28 years. Her male child was born healthy, with normal physical and psychological development over the years. Two of her previous pregnancies were spontaneously terminated in the 1st trimester. Her elder sister has a child born with Down syndrome. The patient denies smoking and alcohol consumption. Her blood analysis reveals the following findings:\n  Measured values\nBeta human chorionic gonadotropin (beta-hCG) High\nPregnancy-associated plasma protein-A (PAPP-A) Low\nWhich of the following is the most appropriate next step in the management of this patient?", "answer": "Recommend chorionic villus sampling with subsequent cell culturing and karyotyping", "options": {"A": "Offer a blood test for rubella virus, cytomegalovirus, and toxoplasma IgG", "B": "Perform an ultrasound examination with nuchal translucency and crown-rump length measurement", "C": "Recommend chorionic villus sampling with subsequent cell culturing and karyotyping", "D": "Recommend amniocentesis with subsequent cell culturing and karyotyping", "E": "Schedule a quadruple test at the 15th week of pregnancy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 63-year-old man is brought to the emergency department by the police after he was found in the streets lying unconscious on the ground. Both of his pupils are normal in size and reactive to light. There are no obvious signs of head trauma. The finger prick test shows a blood glucose level of 20 mg/dL. He has been brought to the emergency department due to acute alcohol intoxication several times. The vital signs include: blood pressure 100/70 mm Hg, heart rate 110/min, respiratory rate 22/min, and temperature 35℃ (95℉). On general examination, he is pale looking and disheveled with an odor of EtOH. On physical examination, the abdomen is soft and non-tender with no hepatosplenomegaly. After giving a bolus of intravenous dextrose, thiamine, and naloxone, he spontaneously opens his eyes. Blood and urine samples are drawn for toxicology screening. The blood alcohol level comes out to be 300 mg/dL. What will be the most likely laboratory findings in this patient?", "answer": "Macrocytosis MCV > 100fL", "options": {"A": "Schistocytes", "B": "Hypersegmented neutrophils", "C": "Sickle cells", "D": "Macrocytosis MCV > 100fL", "E": "Howell-Jolly bodies"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old man comes to his primary care physician with a 6-month history of bilateral calf pain. The pain usually occurs after walking his dog a few blocks and is more severe on the right side. He has coronary artery disease, essential hypertension, and type 2 diabetes mellitus. He has smoked two packs of cigarettes daily for 43 years and drinks two alcoholic beverages a day. Current medications include metformin, lisinopril, and aspirin. He is 183 cm (5 ft 11 in) tall and weighs 113 kg (250 lb); BMI is 34.9 kg/m2. His temperature is 37°C (98.6°F), pulse is 84/min, and blood pressure is 129/72 mm Hg. Cardiac examination shows a gallop without murmurs. The legs have shiny skin with reduced hair below the knee. Femoral and popliteal pulses are palpable bilaterally. Dorsal pedal pulses are 1+ on the left and absent on the right. Ankle-brachial index (ABI) is performed in the office. ABI is 0.5 in the right leg, and 0.6 in the left leg. Which of the following is the most appropriate initial step in management?", "answer": "Graded exercise therapy", "options": {"A": "Graded exercise therapy", "B": "Propranolol therapy", "C": "Spinal cord stimulation", "D": "Vascular bypass surgery", "E": "Percutaneous transluminal angioplasty with stenting"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 25-year-old man comes to the physician because of a 1-week history of fever and fluid release from painful lumps in his right groin. He had an atraumatic ulceration of his penis about 1 month ago that was not painful and resolved on its own within 1 week. He works at an animal shelter for abandoned pets. He is sexually active with multiple male partners and does not use condoms. His temperature is 38.5°C (101.3°F). Examination of the groin shows numerous tender nodules with purulent discharge. The remainder of the examination shows no abnormalities. Which of the following is the most likely causal pathogen?", "answer": "Chlamydia trachomatis", "options": {"A": "Bartonella henselae", "B": "Treponema pallidum", "C": "Chlamydia trachomatis", "D": "Haemophilus ducreyi", "E": "Klebsiella granulomatis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 67-year-old man comes to the physician because of numbness and burning sensation of his legs for the past week. He also complains that his stools have been larger and rougher than usual. He has non-Hodgkin lymphoma and is currently receiving chemotherapy with prednisone, vincristine, rituximab, cyclophosphamide, and doxorubicin. He has received 4 cycles of chemotherapy, and his last chemotherapy cycle was 2 weeks ago. His temperature is 37.1°C (98.8°F), pulse is 89/min, and blood pressure is 122/80 mm Hg. Examination shows decreased muscle strength in the distal muscles of the lower extremities. Ankle jerk is 1+ bilaterally and knee reflex is 2+ bilaterally. Sensation to pain, vibration, and position is decreased over the lower extremities. Serum concentrations of glucose, creatinine, electrolytes, and calcium are within the reference range. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Adverse effect of vincristine", "options": {"A": "Adverse effect of vincristine", "B": "Spinal cord compression", "C": "Paraneoplastic autoantibodies", "D": "Guillain-Barré syndrome", "E": "Charcot–Marie–Tooth disease"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 76-year-old Japanese man is admitted to the hospital because of a 3-month history of loose stools and worsening peripheral edema. He also reports fatigue, a 10-pound weight loss over the past 6 weeks, and a tingling sensation in his hands and feet over the same time period. Aside from the family dog, he has not had contact with animals for over 1 year and has not traveled outside the country. He has hypertension and benign prostatic hyperplasia. Five years ago, he underwent a partial gastrectomy with jejunal anastomosis for gastric cancer. Current medications include hydrochlorothiazide and tamsulosin. His temperature is 36.8°C (98.2°F), pulse is 103/min, and blood pressure is 132/83 mm Hg. Examination shows a soft and nontender abdomen. There is a well-healed scar on the upper abdomen. Cardiopulmonary examination shows no abnormalities. The conjunctivae appear pale. Sensation to vibration and position is absent over the lower extremities. His hemoglobin concentration is 9.9 g/dL, MCV is 108 μm3, total protein 3.9 g/dL, and albumin 1.9 g/dL. Which of the following is the most likely cause of this patient's condition?", "answer": "Bacterial overgrowth", "options": {"A": "Neoplastic growth", "B": "Increased intestinal motility", "C": "Bacterial overgrowth", "D": "Bypass of the pyloric sphincter", "E": "Anastomotic stricture"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-week-old male presents to the pediatrician for vomiting. His parents report that three weeks ago the patient began vomiting after meals. They say that the vomitus appears to be normal stomach contents without streaks of red or green. His parents have already tried repositioning him during mealtimes and switching his formula to eliminate cow’s milk and soy. Despite these adjustments, the vomiting has become more frequent and forceful. The patient’s mother reports that he is voiding about four times per day and that his urine looks dark yellow. The patient has fallen one standard deviation off his growth curve. The patient's mother reports that the pregnancy was uncomplicated other than an episode of sinusitis in the third trimester, for which she was treated with azithromycin. In the office, the patient's temperature is 98.7°F (37.1°C), blood pressure is 58/41 mmHg, pulse is 166/min, and respirations are 16/min. On physical exam, the patient looks small for his age. His abdomen is soft, non-tender, and non-distended.\n\nWhich of the following is the best next step in management?", "answer": "Intravenous hydration", "options": {"A": "Abdominal ultrasound", "B": "Intravenous hydration", "C": "MRI of the head", "D": "Pyloromyotomy", "E": "Thickening feeds"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying nutritional deficiencies in humans. A group of healthy volunteers are started on a diet deficient in pantothenic acid. After 4 weeks, several of the volunteers develop irritability, abdominal cramps, and burning paresthesias of their feet. These symptoms are fully reversed after reintroduction of pantothenic acid to their diet. The function of which of the following enzymes was most likely impaired in the volunteers during the study?", "answer": "Alpha-ketoglutarate dehydrogenase", "options": {"A": "Gamma-glutamyl carboxylase", "B": "Methionine synthase", "C": "Dopamine beta-hydroxylase", "D": "Glutathione reductase", "E": "Alpha-ketoglutarate dehydrogenase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 64-year-old man presents to his primary care physician's office for a routine check-up. His past medical history is significant for type 2 diabetes mellitus, hypertension, chronic atrial fibrillation, and ischemic cardiomyopathy. On his last visit three months ago, he was found to have hyperkalemia, at which time lisinopril and spironolactone were removed from his medication regimen. Currently, his medications include coumadin, aspirin, metformin, glyburide, metoprolol, furosemide, and amlodipine. His T is 37 C (98.6 F), BP 154/92 mm Hg, HR 80/min, and RR 16/min. His physical exam is notable for elevated jugular venous pressure, an S3 heart sound, and 1+ pitting pedal edema. His repeat lab work at the current visit is as follows:\n\nSodium: 138 mEq/L, potassium: 5.7 mEq/L, chloride 112 mEq/L, bicarbonate 18 mEq/L, BUN 29 mg/dL, and creatinine 2.1 mg/dL.\n\nWhich of the following is the most likely cause of this patient's acid-base and electrolyte abnormalities?", "answer": "Renal tubular acidosis", "options": {"A": "Furosemide", "B": "Chronic renal failure", "C": "Glyburide", "D": "Renal tubular acidosis", "E": "Amlodipine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old boy comes to the physician because of a 3-month history of pain in his right shoulder. He reports that he has stopped playing for his high school football team because of persistent difficulty lifting his right arm. Physical examination shows impaired active abduction of the right arm from 0 to 15 degrees. After passive abduction of the right arm to 15 degrees, the patient is able to raise his arm above his head. The dysfunctional muscle in this patient is most likely to be innervated by which of the following nerves?", "answer": "Suprascapular nerve", "options": {"A": "Suprascapular nerve", "B": "Long thoracic nerve", "C": "Axillary nerve", "D": "Upper subscapular nerve", "E": "Accessory nerve"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man is brought to the physician by his son because of gradually progressive yellow discoloration of his skin and generalized pruritus for the past 2 weeks. During this period, his appetite has decreased and he has had a 6.3-kg (14-lb) weight loss. He reports that his stool appears pale and his urine is very dark. Three years ago, he had an episode of acute upper abdominal pain that was treated with IV fluids, NSAIDs, and dietary modification. He has stopped drinking alcohol since then; he used to drink 1–2 beers daily for 40 years. He has smoked a pack of cigarettes daily for the past 50 years. His vital signs are within normal limits. Physical examination shows yellowing of the conjunctivae and skin. The abdomen is soft and nontender; a soft, cystic mass is palpated in the right upper quadrant. Serum studies show:\nBilirubin, total 5.6 mg/dL\nDirect 4.8 mg/dL\nAlkaline phosphatase 192 U/L\nAST 32 U/L\nALT 34 U/L\nAbdominal ultrasonography shows an anechoic cystic mass in the subhepatic region and dilation of the intrahepatic and extrahepatic bile ducts. Which of the following is the most likely diagnosis?\"", "answer": "Pancreatic adenocarcinoma", "options": {"A": "Pancreatic adenocarcinoma", "B": "Choledocholithiasis", "C": "Alcoholic hepatitis", "D": "Cholecystitis", "E": "Budd-Chiari syndrome"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-day-old infant dies of severe respiratory distress following a gestation complicated by persistent oligohydramnios. Upon examination at autopsy, the left kidney is noted to selectively lack cortical and medullary collecting ducts. From which of the following embryological structures do the cortical and medullary collecting ducts arise?", "answer": "Ureteric bud", "options": {"A": "Pronephros", "B": "Mesonephros", "C": "Paramesonephric duct", "D": "Metanephric mesenchyme", "E": "Ureteric bud"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2-year-old child is brought to the emergency department with rapid breathing and a severe cyanotic appearance of his lips, fingers, and toes. He is known to have occasional episodes of mild cyanosis, especially when he is extremely agitated. This is the worst episode of this child’s life, according to his parents. He was born with an APGAR score of 8 via a normal vaginal delivery. His development is considered delayed compared to children of his age. History is significant for frequent squatting after strenuous activity. On auscultation, there is evidence of a systolic ejection murmur at the left sternal border. On examination, his oxygen saturation is 71%, blood pressure is 81/64 mm Hg, respirations are 42/min, pulse is 129/min, and temperature is 36.7°C (98.0°F). Which of the following will most likely be seen on chest x-ray (CXR)?", "answer": "Boot-shaped heart", "options": {"A": "Egg on a string", "B": "Boot-shaped heart", "C": "Displaced tricuspid valve", "D": "Pre-ductal coarctation of the aorta", "E": "Atrial septal defect"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 11-year-old boy is brought to a pediatrician by his parents with the complaint of progressive behavioral problems for the last 2 years. His parents report that he always looks restless at home and is never quiet. His school teachers frequently complain that he cannot remain seated for long during class, often leaving his seat to move around the classroom. A detailed history of his symptoms suggests a diagnosis of attention-deficit/hyperactivity disorder. The parents report that he has taken advantage of behavioral counseling several times without improvement. The pediatrician considers pharmacotherapy and plans to start methylphenidate at a low dose, followed by regular follow-up. Based on the side effect profile of the medication, which of the following components of the patient’s medical history should the pediatrician obtain before starting the drug?", "answer": "Past history of Kawasaki disease", "options": {"A": "Past history of recurrent wheezing", "B": "Past history of Kawasaki disease", "C": "Past history of recurrent fractures", "D": "Past history of idiopathic thrombocytopenic purpura", "E": "Past history of Guillain-Barré syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-year-old boy with a history of recurrent respiratory infections is brought to the physician for a follow-up examination. His height and weight are both at the 20th percentile. Crackles are heard in both lower lung fields. Cardiac auscultation shows a grade 3/6 holosystolic murmur over the left lower sternal border and a diastolic rumble heard best at the apex. If left untreated, this patient is most likely to develop which of the following?", "answer": "Digital clubbing", "options": {"A": "Thrombocytosis", "B": "Secondary hypertension", "C": "Aortic dissection", "D": "Digital clubbing", "E": "Chronic kidney disease\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 57-year-old man comes to the emergency department because of acute retrosternal chest pain that radiates to his back. The pain started suddenly while he was having dinner. A few moments prior to the onset of the pain, he experienced discomfort when trying to eat or drink anything. On the way to the hospital he took a sublingual nitrate tablet that he had at home, which helped relieve the pain. His pulse is 80/min, respirations are 14/min, and blood pressure is 144/88 mm Hg. Examination shows no other abnormalities. An ECG shows a normal sinus rhythm with no ST-segment abnormalities. An esophagogram is done and shows areas of diffuse, uncoordinated spasms in several segments along the length of the esophagus. This patient's condition is most likely to show which of the following findings?", "answer": "Esophageal manometry shows simultaneous multi-peak contractions", "options": {"A": "Esophageal manometry shows simultaneous multi-peak contractions", "B": "Endoscopy shows multiple mucosal erosions", "C": "Ultrasonography shows a mass at the gastroesophageal junction", "D": "Serology shows elevated CK-MB levels", "E": "Esophageal manometry shows hypertensive contractions"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman presents with fever, abdominal pain, and bloody bowel movements. She says her symptoms onset 2 days ago and have not improved. She describes the abdominal pain as moderate, cramping in character, and poorly localized. 1 week ago, she says she was on a camping trip with her friends and had barbecued chicken which she thought tasted strange. The patient denies any chills, hemoptysis, hematochezia, or similar symptoms in the past. The vital signs include: pulse 87/min and temperature 37.8°C (100.0°F). Physical examination is significant for moderate tenderness to palpation in the periumbilical region with no rebound or guarding. Stool is guaiac positive. Which of the following is a complication associated with this patient’s most likely diagnosis?", "answer": "Guillain-Barré syndrome", "options": {"A": "Typhoid", "B": "Appendicitis", "C": "Toxic megacolon", "D": "Guillain-Barré syndrome", "E": "Hemolytic uremic syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old female presents to her pediatrician due to lack of menstruation. She states that she developed breasts 4 years ago but has not experienced menses yet. The patient denies abdominal pain and has no past medical history. Her mother underwent menarche at age 13. The patient is a volleyball player at school, is single, and has never attempted intercourse. At this visit, her temperature is 98.3°F (36.8°C), blood pressure is 110/76 mmHg, pulse is 72/min, and respirations are 14/min. She is 5 feet 7 inches tall and weighs 116 pounds (BMI 18.2 kg/m^2). Exam shows Tanner IV breasts, Tanner I pubic hair, and minimal axillary hair. External genitalia are normal, but the vagina is a 5-centimeter blind pouch. Genetic testing is performed. Which of the following is the best next step in management?", "answer": "Gonadectomy", "options": {"A": "Gonadectomy", "B": "Estrogen replacement therapy", "C": "Vaginoplasty", "D": "Obtain FSH and estrogen levels", "E": "ACTH stimulation test"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old man comes to the physician because of a 6-month history of progressively worsening urinary frequency. He feels the urge to urinate every hour or two, which restricts his daily activities and interferes with his sleep. He has no fever, hematuria, or burning pain on micturition. He has hypertension and type 2 diabetes mellitus. Current medications include metformin and amlodipine. He does not smoke and drinks 1 to 2 beers daily. His vital signs are within normal limits. Abdominal examination shows no abnormalities. Digital rectal examination shows a nontender, firm, symmetrically enlarged prostate with no nodules. Which of the following is the most appropriate next step in management?", "answer": "Urinalysis", "options": {"A": "Urinalysis", "B": "Prostate ultrasonography", "C": "Urine cytology", "D": "Serum prostate-specific antigen level", "E": "Uroflowmetry"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 5-year-old boy is brought to the pediatric clinic for evaluation of fever, pain, swelling in the left leg, and limping. Review of systems and history is otherwise unremarkable. The vital signs include: pulse 110/min, temperature 38.1°C (100.6°F), and blood pressure 100/70 mm Hg. On examination, there is a tender swelling over the lower part of his left leg. Which 1 of the following X-ray findings is most suggestive of Ewing’s sarcoma?", "answer": "X-ray showing lytic bone lesion with periosteal reaction", "options": {"A": "Mixed lytic and blastic appearance in the X-ray", "B": "X-ray showing lytic bone lesion with periosteal reaction", "C": "X-ray showing broad-based projections from the surface of the bone", "D": "X-ray showing deep muscle plane displacement from the metaphysis", "E": "X-ray showing a sharply marginated radiolucent area within the apophysis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old homeless woman presents to an urgent care clinic complaining of vaginal bleeding. She also has vague lower right abdominal pain which started a few hours ago and is increasing in intensity. The medical history is significant for chronic hepatitis C infection, and she claims to take a pill for it ‘every now and then.’ The temperature is 36.0°C (98.6°F), the blood pressure is 110/70 mmHg, and the pulse is 80/min. The abdominal examination is positive for localized right adnexal tenderness; no rebound tenderness or guarding is noted. A transvaginal ultrasound confirms a 2.0 cm gestational sac in the right fallopian tube. What is the next appropriate step in the management of this patient? Immunodeficiency (RA, SLE, and Crohns)", "answer": "Surgery", "options": {"A": "Surgery", "B": "IV fluids, then surgery", "C": "Methotrexate", "D": "Pelvic CT without contrast", "E": "Tubal ligation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 29-year-old man presents to the primary care clinic in June for post-discharge follow-up. The patient was recently admitted to the hospital after a motor vehicle collision. At that time he arrived at the emergency department unconscious, hypotensive, and tachycardic. Abdominal CT revealed a hemoperitoneum due to a large splenic laceration; he was taken to the operating room for emergency splenectomy. Since that time he has recovered well without complications. Prior to the accident, he was up-to-date on all of his vaccinations. Which of the following vaccinations should be administered at this time?", "answer": "13-valent pneumococcal conjugate vaccine", "options": {"A": "13-valent pneumococcal conjugate vaccine", "B": "Inactivated (intramuscular) influenza vaccine", "C": "Live attenuated (intranasal) influenza vaccine", "D": "Measles-mumps-rubella vaccine", "E": "Tetanus booster vaccine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-year-old boy is brought to the emergency department by his mother after cutting his buttock on a piece of broken glass. There is a 5-cm curvilinear laceration over the patient's right buttock. His vital signs are unremarkable. The decision to repair the laceration is made. Which of the following will offer the longest anesthesia for the laceration repair?", "answer": "Bupivacaine with epinephrine", "options": {"A": "Bupivacaine", "B": "Bupivacaine with epinephrine", "C": "Lidocaine", "D": "Lidocaine mixed with bupivacaine", "E": "Lidocaine with epinephrine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old woman comes to the emergency department because of a 2-day history of worsening upper abdominal pain. She reports nausea and vomiting, and is unable to tolerate oral intake. She appears uncomfortable. Her temperature is 38.1°C (100.6°F), pulse is 92/min, respirations are 18/min, and blood pressure is 132/85 mm Hg. Examination shows yellowish discoloration of her sclera. Her abdomen is tender in the right upper quadrant. There is no abdominal distention or organomegaly. Laboratory studies show:\nHemoglobin 13 g/dL\nLeukocyte count 16,000/mm3\nSerum\nUrea nitrogen\n25 mg/dL\nCreatinine 2 mg/dL\nAlkaline phosphatase 432 U/L\nAlanine aminotransferase 196 U/L\nAspartate transaminase 207 U/L\nBilirubin\nTotal 3.8 mg/dL\nDirect 2.7 mg/dL\nLipase 82 U/L (N = 14–280)\nUltrasound of the right upper quadrant shows dilated intrahepatic and extrahepatic bile ducts and multiple hyperechoic spheres within the gallbladder. The pancreas is not well visualized. Intravenous fluid resuscitation and antibiotic therapy with ceftriaxone and metronidazole is begun. Twelve hours later, the patient appears acutely ill and is not oriented to time. Her temperature is 39.1°C (102.4°F), pulse is 105/min, respirations are 22/min, and blood pressure is 112/82 mm Hg. Which of the following is the most appropriate next step in management?\"", "answer": "Endoscopic retrograde cholangiopancreatography\n\"", "options": {"A": "Abdominal CT scan", "B": "Laparoscopic cholecystectomy", "C": "Percutaneous cholecystostomy", "D": "Extracorporeal shock wave lithotripsy", "E": "Endoscopic retrograde cholangiopancreatography\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 49-year-old woman presents to the office because of tremors for 2 months. She says that her hands have been shaking a lot, especially when she feels stressed. In addition, she has been sweating more than usual and has lost 8 kg (17.6 lb) in the last 2 months. She has a past medical history of vitiligo. Her vital signs are a heart rate of 98/min, a respiratory rate of 14/min, a temperature of 37.6°C (99.7°F), and a blood pressure of 115/75 mm Hg. Physical examination shows a fine, bilateral hand tremor and a diffuse goiter. Which of the following hormonal imbalances is most likely present?", "answer": "Low TSH, high free T4, and high free T3", "options": {"A": "High TSH, high freeT4, and high free T3", "B": "High TSH, low free T4, and low free T3", "C": "High TSH, normal free T4, and normal free T3", "D": "Low TSH, high free T4, and high free T3", "E": "Low TSH, normal free T4, and normal free T3"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 14-year-old boy is brought to the emergency department because of acute left-sided chest pain and dyspnea following a motor vehicle accident. His pulse is 122/min and blood pressure is 85/45 mm Hg. Physical examination shows distended neck veins and tracheal displacement to the right side. The left chest is hyperresonant to percussion and there are decreased breath sounds. This patient would most benefit from needle insertion at which of the following anatomical sites?", "answer": "2nd left intercostal space along the midclavicular line", "options": {"A": "2nd left intercostal space along the midclavicular line", "B": "5th left intercostal space along the midaxillary line", "C": "8th left intercostal space along the posterior axillary line", "D": "Subxiphoid space in the left sternocostal margin", "E": "5th left intercostal space along the midclavicular line"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Five days after undergoing an open colectomy and temporary colostomy for colon cancer, a 73-year-old man develops severe pain and swelling of the left calf. He was diagnosed with colon cancer 3 months ago. He has hypothyroidism and hypertension. His father died of colon cancer at the age of 68. He does not smoke. Prior to admission, his medications included levothyroxine, amlodipine, and carvedilol. Since the surgery, he has also been receiving unfractionated heparin, morphine, and piperacillin-tazobactam. He is 172 cm (5 ft 8 in) tall and weighs 101 kg (223 lb); BMI is 34.1 kg/m2. He appears uncomfortable. His temperature is 38.1°C (100.6°F), pulse is 103/min, and blood pressure is 128/92 mm Hg. Examination shows multiple necrotic lesions over bilateral thighs. The left calf is erythematous, tender, and swollen. Dorsiflexion of the left foot elicits pain behind the knee. The abdomen is soft and nontender. There is a healing midline incision and the colostomy is healthy and functioning. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13.6 g/dL\nLeukocyte count 12,100/mm3\nPlatelet count 78,000/mm3\nProthrombin time 18 seconds (INR = 1.1)\nActivated partial thromboplastin time 46 seconds\nSerum\nNa+ 138 mEq/L\nCl- 103 mEq/L\nK+ 4.1 mEq/L\nUrea nitrogen 18 mg/dL\nGlucose 101 mg/dL\nCreatinine 1.1 mg/dL\nWhich of the following is the most appropriate next step in management?\"", "answer": "Switch from unfractionated heparin to argatroban therapy", "options": {"A": "Switch from unfractionated heparin to warfarin therapy", "B": "Switch from unfractionated heparin to argatroban therapy", "C": "Administer vitamin K", "D": "Transfuse platelet concentrate", "E": "Administer fresh frozen plasma\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 13-year-old boy is brought to the physician because of a lump beneath his right nipple that he discovered 1 week ago while showering. He has allergic rhinitis treated with cetirizine. He is at the 65th percentile for height and 80th percentile for weight. Examination shows a mildly tender, firm, 2-cm subareolar mass in the right breast; there are no nipple or skin changes. The left breast shows no abnormalities. Sexual development is Tanner stage 3. Which of the following is the most likely explanation for this patient's breast lump?", "answer": "Normal development", "options": {"A": "Leydig cell tumor", "B": "Adverse effect of medication", "C": "Invasive ductal carcinoma", "D": "Normal development", "E": "Hyperprolactinemia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old female presents with a seven-day history of abdominal pain, and now bloody diarrhea that brings her to her primary care physician. Review of systems is notable for a 12-pound unintentional weight loss and intermittent loose stools. She has a family history notable for a father with CAD and a mother with primary sclerosing cholangitis. Upon further workup, she is found to have the following on colonoscopy and biopsy, Figures A and B respectively. Serum perinuclear antineutrophil cytoplasmic antibodies (P-ANCA) is positive. This patient's disease is likely to also include which of the following features?", "answer": "Continuous progression beginning in the rectum", "options": {"A": "Perianal disease", "B": "Continuous progression beginning in the rectum", "C": "Fistulae and stricture formation", "D": "Worse disease severity near the ileocecal valve", "E": "Cobblestoning and skip lesions"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old man comes to the physician for a routine health maintenance examination. He feels well but has had several episodes of “finger pallor” over the past 4 months. During these episodes, the 4th finger of his left hand turns white. The color usually returns within 20 minutes, followed by redness and warmth of the finger. The episodes are not painful. The complaints most commonly occur on his way to work, when it is very cold outside. One time, it happened when he was rushing to the daycare center because he was late for picking up his daughter. The patient has gastroesophageal reflux disease treated with lansoprazole. His vital signs are within normal limits. The blood flow to the hand is intact on compression of the ulnar artery at the wrist, as well as on compression of the radial artery. When the patient is asked to immerse his hands in cold water, a change in the color of the 4th digit of his left hand is seen. A photograph of the affected hand is shown. His hemoglobin concentration is 14.2 g/dL, serum creatinine is 0.9 mg/dL, and ESR is 35 mm/h. Which of the following is the most appropriate next step in management?", "answer": "Serologic testing", "options": {"A": "Discontinue lansoprazole", "B": "Oral aspirin", "C": "Digital subtraction angiography", "D": "Serologic testing", "E": "Topical nitroglycerin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy presents to your office with facial eczema. He has a history of recurrent infections, including multiple episodes of pneumonia that lasted several weeks and otitis media. Laboratory measurements of serum immunoglobulins show increased IgE and IgA but decreased IgM. Which of the following additional abnormalities would you expect to observe in this patient?", "answer": "Thrombocytopenia", "options": {"A": "Thrombocytopenia", "B": "Leukopenia", "C": "Anemia", "D": "Pancreatic insufficiency", "E": "NADPH oxidase deficiency"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 26-year-old student arrives to student health for persistent diarrhea. She states that for the past 2 months she has had foul-smelling diarrhea and abdominal cramping. She also reports increased bloating, flatulence, and an unintentional 4 lb weight loss. Prior to 2 months ago, she had never felt these symptoms before. She denies other extra-gastrointestinal symptoms. The patient is an avid hiker and says her symptoms have caused her to miss recent camping trips. The patient has tried to add more fiber to her diet without relief. She feels her symptoms worsen with milk or cheese. Her medical history is insignificant and she takes no medications. She drinks whiskey socially, but denies smoking tobacco or using any illicit drugs. She is sexually active with her boyfriend of 2 years. She went to Mexico 6 months ago and her last multi-day backpacking trek was about 3 months ago in Vermont. Physical examination is unremarkable. A stool sample is negative for fecal occult blood. Which of the following is an associated adverse effect of the most likely treatment given to manage the patient’s symptoms?", "answer": "Disulfiram-like reaction", "options": {"A": "Disulfiram-like reaction", "B": "Osteoporosis", "C": "Photosensitivity", "D": "QT prolongation", "E": "Tendon rupture"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 71-year-old man with hypertension comes to the physician for a follow-up examination. Cardiovascular exam shows the point of maximal impulse to be in the mid-axillary line. A transthoracic echocardiogram shows concentric left ventricular hypertrophy with a normal right ventricle. Which of the following is the most likely underlying mechanism of this patient's ventricular hypertrophy?", "answer": "Accumulation of sarcomeres in parallel", "options": {"A": "Accumulation of glycogen", "B": "Accumulation of protein fibrils", "C": "Deposition of endomyocardial collagen", "D": "Accumulation of sarcomeres in parallel", "E": "Infiltration of T lymphocytes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 62-year-old man comes to the physician because of increased frequency of urination. He also says that he needs to urinate 4 to 5 times nightly and has difficulty initiating a urinary stream. He has had several episodes of acute cystitis treated with ciprofloxacin during the past year. Digital rectal examination shows a firm, symmetrically enlarged, non-tender prostate. This patient is most likely to develop which of the following complications?", "answer": "Inflammation of the renal interstitium", "options": {"A": "Abscess formation in the prostate", "B": "Irreversible decrease in renal function", "C": "Impaired intracavernosal blood flow", "D": "Inflammation of the renal interstitium", "E": "Blastic bone lesions"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 9-year-old boy is brought to a psychologist by his mother because his teachers frequently complain about his behavioral problems at school. The patient’s mother reports that his concerning behavior started at a young age. She says he is disrespectful to family members and to his teachers at school. He also talks back to everyone. Grounding him and limiting his freedom has not improved his behavior. His grades have never been very good, and he is quite isolated at school. After a further review of the patient’s medical history and a thorough physical exam, the physician confirms the diagnosis of oppositional defiant disorder. Which of the following additional symptoms would most likely present in this patient?", "answer": "Blaming others for his own misbehavior", "options": {"A": "History of deliberately damaging furniture", "B": "Blaming others for his own misbehavior", "C": "Staying out of home at nights despite restrictions", "D": "Fights at school", "E": "Frequently leaving his seat during class despite instructions by the teacher"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old woman comes to the physician because of stiffness and pain in multiple joints. She says that the fingers on both of her hands have become increasingly stiff and difficult to move over the past 8 months. She also complains of nails that break easily and look spotty as well as chronic back pain. She had a urinary tract infection a year ago that was treated with antibiotics. She is sexually active with 2 male partners and uses condoms inconsistently. Her vitals are within normal limits. A photograph of her right hand is shown. There are multiple, well-demarcated red plaques with silvery-white scales over the shins and back. Serum studies show a negative rheumatoid factor and ANA. Which of the following is the most likely diagnosis?", "answer": "Psoriatic arthritis\n\"", "options": {"A": "Secondary syphilis", "B": "Ankylosing spondylitis", "C": "Rheumatoid arthritis", "D": "Systemic lupus erythematosus", "E": "Psoriatic arthritis\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 70-year-old women presents to her primary care physician with sudden episodes of dizziness that resolve in certain positions. On further questioning she describes a false sense of motion with occasional spinning sensation consistent with vertigo. She denies any recent illnesses or hearing loss aside from presbycusis. Her vital signs are normal. During the physical exam the the patient reports an episode of vertigo after transitioning from sitting to supine and horizontal nystagmus is concurrently noted. What is the mostly likely diagnosis?", "answer": "Benign Paroxysmal Positional Vertigo (BPPV)", "options": {"A": "Vestibular migraine", "B": "Meniere's disease", "C": "Labyrinthitis", "D": "Benign Paroxysmal Positional Vertigo (BPPV)", "E": "Vestibular neuritis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 6-year-old girl is brought to the physician by her father because of a 3-day history of sore throat, abdominal pain, nausea, vomiting, and high fever. She has been taking acetaminophen for the fever. Physical examination shows cervical lymphadenopathy, pharyngeal erythema, and a bright red tongue. Examination of the skin shows a generalized erythematous rash with a rough surface that spares the area around the mouth. Which of the following is the most likely underlying mechanism of this patient's rash?", "answer": "Erythrogenic toxin-induced cytokine release", "options": {"A": "Anti-M protein antibody cross-reaction", "B": "Subepithelial immune complex deposition", "C": "Erythrogenic toxin-induced cytokine release", "D": "Bacterial invasion of the deep dermis", "E": "Paramyxovirus-induced cell damage"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 37-year-old woman is being evaluated for difficulty with swallowing for the past few months. She explains that she experiences difficulty swallowing solid foods only. Her medical history is relevant for hypothyroidism and migraines. Her current medications include daily levothyroxine and acetaminophen as needed for pain. The vital signs include blood pressure 110/90 mm Hg, pulse rate 55/min, and respiratory rate 12/min. On physical examination, her abdomen is non-tender. Her voice is hoarse, but there is no pharyngeal hyperemia on oral examination. On cardiac auscultation, an opening snap followed by an early to mid-diastolic rumble is heard over the apex. A barium swallow X-ray is performed and is unremarkable. Echocardiography shows an enlarged left atrium and abnormal blood flow through 1 of the atrioventricular valves. What is the most likely valve abnormality seen in this patient?", "answer": "Mitral valve stenosis", "options": {"A": "Mitral valve stenosis", "B": "Mitral valve regurgitation", "C": "Aortic valve stenosis", "D": "Aortic valve regurgitation", "E": "Mitral valve prolapse"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "In a lab experiment, a researcher treats early cells of the erythrocyte lineage with a novel compound called Pb82. Pb82 blocks the first step of heme synthesis. However, the experiment is controlled such that the cells otherwise continue to develop into erythrocytes. At the end of the experiment, the cells have developed into normal erythrocytes except that they are devoid of heme. A second compound, anti-Pb82 is administered which removes the effect of Pb82.\n\nWhich of the following is likely to be true of the mature red blood cells in this study?", "answer": "The cells will not produce heme since they lack mitochondria", "options": {"A": "The cells will now produce heme", "B": "The cells will not produce heme since they lack mitochondria", "C": "The cells will not produce heme because they lack cytosol", "D": "The cells will not produce heme because they lack nucleoli", "E": "The cells will not produce heme because they lack iron"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old man presents with upper GI (upper gastrointestinal) bleeding. The patient is known to have a past medical history of peptic ulcer disease and was previously admitted 4 years ago for the same reason. He uses proton-pump inhibitors for his peptic ulcer. Upon admission, the patient is placed on close monitoring, and after 8 hours, his hematocrit is unchanged. The patient has also been hemodynamically stable after initial fluid resuscitation. An upper endoscopy is performed. Which of the following endoscopy findings most likely indicates that this patient will not experience additional GI bleeding in the next few days?", "answer": "Clean-based ulcer", "options": {"A": "Visible non-bleeding vessel", "B": "Gastric ulcer with arteriovenous malformations", "C": "Visible bleeding vessel", "D": "Adherent clot on ulcer", "E": "Clean-based ulcer"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A study is conducted to find an association between serum cholesterol and ischemic heart disease. Data is collected, and patients are classified into either the \"high cholesterol\" or \"normal cholesterol\" group and also into groups whether or not the patient experiences stable angina. Which type of data analysis is most appropriate for this study?", "answer": "Chi-squared", "options": {"A": "Analysis of variance", "B": "Attributable risk", "C": "Chi-squared", "D": "Pearson correlation", "E": "T-test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 42-year-old man is brought to the emergency department by his wife because of a 1-day history of progressive confusion. He recently lost his job. He has a history of chronic alcoholism and has been drinking 14 beers daily for the past week. Before this time, he drank 6 beers daily. He appears lethargic. His vital signs are within normal limits. Serum studies show a sodium level of 111 mEq/L and a potassium level of 3.7 mEq/L. Urgent treatment for this patient's current condition increases his risk for which of the following adverse events?", "answer": "Osmotic myelinolysis", "options": {"A": "Wernicke encephalopathy", "B": "Cerebral edema", "C": "Cardiac arrythmia", "D": "Osmotic myelinolysis", "E": "Hyperglycemia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old man presents to his primary care physician for trouble with focus and concentration. The patient states that he has lived at home with his parents his entire life but recently was able to get a job at a local factory. Ever since the patient has started working, he has had trouble focusing at his job. He is unable to stay focused on any task. His boss often observes him \"daydreaming\" with a blank stare off into space. His boss will have to yell at him to startle him back to work. The patient states that he feels fatigued all the time and sometimes will suddenly fall asleep while operating equipment. He has tried going to bed early for the past month but is unable to fall asleep until two hours prior to his alarm. The patient fears that if this continues he will lose his job. Which of the following is the best initial step in management?", "answer": "Bright light therapy", "options": {"A": "Ethosuximide", "B": "Polysomnography", "C": "Bright light therapy", "D": "Modafinil", "E": "Zolpidem"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-year-old boy is brought to the physician because of a 4-day history of fever, headache, earache, and sore throat that is worse when swallowing. He has not had a runny nose or cough. He had a similar problem 1 year ago for which he was prescribed amoxicillin, but after developing a skin rash and facial swelling he was switched to a different medication. His immunizations are up-to-date. He is at the 75th percentile for height and the 50th percentile for weight. His temperature is 38.9°C (102°F), pulse is 136/min, and respirations are 28/min. Examination of the oral cavity reveals a coated tongue, red uvula, and enlarged right tonsil covered by a whitish membrane. The deep cervical lymph nodes are enlarged and tender. A throat swab is taken for culture. What is the next most appropriate step in the management of this patient?", "answer": "Erythromycin", "options": {"A": "Penicillin V", "B": "Total tonsillectomy", "C": "Fluconazole", "D": "Erythromycin", "E": "Cefixime"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old male medical student presents into the university clinic concerned about his stool. He has admitted to spending a great deal of time looking back down into the toilet bowl after he has had a bowel movement and even more time later thinking about all the ways his stool is abnormal. A stool sample was collected and was reported to be grossly normal. The patient understands the results and even agrees with the physician but is still bothered by his thoughts. Two weeks later, he is still thinking about his stool and makes another appointment with a different physician. Which of the following disorders is most likely to be associated with this patient’s condition?", "answer": "Tourette syndrome", "options": {"A": "Tourette syndrome", "B": "Obsessive-compulsive personality disorder", "C": "Major depression", "D": "Paraphilia", "E": "Coprophilia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman G1P0 presents at 38 weeks of gestation for a standard prenatal visit. She endorses occasional mild lower back pain but otherwise remains asymptomatic. Her past medical history is significant for HIV for which she is treated with azidothymidine (AZT). Her vital signs and physical exam are unremarkable. Her current HIV viral titer level is 1,400 copies. If she were to go into labor today, what would be the next and most important step for the prevention of vertical HIV transmission to the newborn?", "answer": "Urge the patient to have a cesarean section delivery", "options": {"A": "Increase AZT dose", "B": "Add nevirapine to the patient’s AZT", "C": "Treat the newborn with AZT following delivery", "D": "Avoid breastfeeding", "E": "Urge the patient to have a cesarean section delivery"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 52-year-old man comes to the physician because of right knee pain and swelling for 2 days. Four days ago, he tripped at home and landed on his knees. He reports an episode of diarrhea 3 weeks ago that resolved after 4 days without treatment. He has a history of hypertension and hypercholesterolemia, and was recently diagnosed with parathyroid disease. He drinks 1–2 ounces of whiskey daily and occasionally more on weekends. His brother has ankylosing spondylitis. Vital signs are within normal limits. Examination of the right leg shows an abrasion below the patella. There is swelling and tenderness of the right knee; range of motion is limited by pain. Arthrocentesis of the right knee joint yields 15 mL of cloudy fluid with a leukocyte count of 26,300/mm3 (91% segmented neutrophils). Microscopic examination of the synovial fluid under polarized light shows rhomboid-shaped, weakly positively birefringent crystals. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Hyperparathyroidism", "options": {"A": "Dyslipidemia", "B": "Local skin abrasion", "C": "Alcohol consumption", "D": "Hyperparathyroidism", "E": "Recent gastrointestinal infection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old man comes to the physician for a routine health maintenance examination. He feels well. He has type 1 diabetes mellitus. His only medication is insulin. He immigrated from Nepal 2 weeks ago . He lives in a shelter. He has smoked one pack of cigarettes daily for the past 5 years. He has not received any routine childhood vaccinations. The patient appears healthy and well nourished. He is 172 cm (5 ft 8 in) tall and weighs 68 kg (150 lb); BMI is 23 kg/m2. His temperature is 36.8°C (98.2°F), pulse is 72/min, and blood pressure is 123/82 mm Hg. Examination shows a healed scar over his right femur. The remainder of the examination shows no abnormalities. A purified protein derivative (PPD) skin test is performed. Three days later, an induration of 13 mm is noted. Which of the following is the most appropriate initial step in the management of this patient?", "answer": "Obtain a chest x-ray", "options": {"A": "Perform interferon-γ release assay", "B": "Obtain a chest x-ray", "C": "Administer isoniazid for 9 months", "D": "Perform PCR of the sputum", "E": "Collect sputum sample for culture"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 38-year-old man is brought to the emergency department after losing consciousness upon rising from his chair at work. The patient has had progressive cough, shortness of breath, fever, and chills for 6 days but did not seek medical attention for these symptoms. He appears distressed, flushed, and diaphoretic. He is 170 cm (5 ft 7 in) tall and weighs 120 kg (265 lbs); BMI is 41.5 kg/m2. His temperature is 39.4°C (102.9°F), pulse is 129/min, respirations are 22/min, and blood pressure is 91/50 mm Hg when supine. Crackles and bronchial breath sounds are heard over the right posterior hemithorax. A 2/6 midsystolic blowing murmur is heard along the left upper sternal border. Examination shows diffuse diaphoresis, flushed extremities, and dullness to percussion over the right posterior hemithorax. The abdomen is soft and nontender. Multiple nurses and physicians have been unable to attain intravenous access. A large-bore central venous catheter is inserted into the right internal jugular vein by standard sterile procedure. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Chest X-ray", "options": {"A": "Administer intravenous levofloxacin", "B": "Echocardiogram", "C": "Bronchoscopy", "D": "CT scan of the chest", "E": "Chest X-ray"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A scientist is studying mechanisms by which cancer drugs work to kill tumor cells. She is working to optimize the function of a drug class in order to reduce toxicity and increase potency for the target. After synthesizing a variety of analogs for the drug class, she tests these new pharmacologic compounds against a panel of potential targets. Assay results show that there is significant binding to a clustered group of proteins. Upon examining these proteins, she finds that the proteins add a phosphate group to an aromatic amino acid sidechain. Which of the following disorders would most likely be treated by this drug class?", "answer": "Chronic myeloid leukemia", "options": {"A": "Brain tumors", "B": "HER2 negative breast cancer", "C": "Chronic myeloid leukemia", "D": "Testicular cancer", "E": "Non-Hodgkin lymphoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A pharmaceutical company conducts a randomized clinical trial in an attempt to show that their new anticoagulant drug, Aclotsaban, prevents more thrombotic events following total knee arthroplasty than the current standard of care. However, a significant number of patients are lost to follow-up or fail to complete treatment according to the study arm to which they were assigned. Despite this, the results for the patients who completed the course of Aclotsaban are encouraging. Which of the following techniques is most appropriate to use in order to attempt to prove the superiority of Aclotsaban?", "answer": "Intention-to-treat analysis", "options": {"A": "Per-protocol analysis", "B": "Intention-to-treat analysis", "C": "As-treated analysis", "D": "Sub-group analysis", "E": "Non-inferiority analysis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old woman with a history of alcoholic cirrhosis and recurrent esophageal varices who recently underwent transjugular intrahepatic portosystemic shunt (TIPS) placement is brought to the emergency room by her daughter due to confusion and agitation. Starting this morning, the patient has appeared sleepy, difficult to arouse, and slow to respond to questions. Her temperature is 97.6°F (36.4°C), blood pressure is 122/81 mmHg, pulse is 130/min, respirations are 22/min, and oxygen saturation is 98% on room air. She repeatedly falls asleep and is combative during the exam. Laboratory values are notable for a potassium of 3.0 mEq/L. The patient is given normal saline with potassium. Which of the following is the most appropriate treatment for this patient?", "answer": "Lactulose", "options": {"A": "Ciprofloxacin", "B": "Lactulose", "C": "Nadolol", "D": "Protein-restricted diet", "E": "Rifampin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old man comes to the physician because of a 1-week history of weakness in the fingers of his right hand. One week ago, he experienced sudden pain in his right forearm during weight training. He has no history of serious illness. Physical examination shows impaired flexion of the proximal interphalangeal joints, while flexion of the distal interphalangeal joints is intact. Which of the following muscles is most likely injured?", "answer": "Flexor digitorum superficialis", "options": {"A": "Palmaris longus", "B": "Flexor carpi radialis", "C": "Flexor carpi ulnaris", "D": "Flexor digitorum superficialis", "E": "Flexor digitorum profundus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old homeless man is brought to the emergency department by the police. He was found intoxicated and passed out in a library. The patient has a past medical history of IV drug abuse, diabetes, alcohol abuse, and malnutrition. The patient has been hospitalized previously for multiple episodes of pancreatitis and sepsis. Currently, the patient is minimally responsive and only withdraws his extremities in response to painful stimuli. His temperature is 99.5°F (37.5°C), blood pressure is 90/48 mmHg, pulse is 150/min, respirations are 17/min, and oxygen saturation is 95% on room air. Physical exam is notable for tachycardia, a diastolic murmur at the left lower sternal border, and bilateral crackles on pulmonary exam. The patient is started on IV fluids, vancomycin, and piperacillin-tazobactam. Laboratory values are ordered as seen below.\n\nHemoglobin: 9 g/dL\nHematocrit: 30%\nLeukocyte count: 11,500/mm^3 with normal differential\nPlatelet count: 297,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.0 mEq/L\nHCO3-: 28 mEq/L\nBUN: 33 mg/dL\nGlucose: 60 mg/dL\nCreatinine: 1.7 mg/dL\nCa2+: 9.7 mg/dL\nPT: 20 seconds\naPTT: 60 seconds\nAST: 1,010 U/L\nALT: 950 U/L\n\nThe patient is admitted to the medical floor. Five days later, the patient's neurological status has improved. His temperature is 99.5°F (37.5°C), blood pressure is 130/90 mmHg, pulse is 90/min, respirations are 11/min, and oxygen saturation is 99% on room air. Laboratory values are repeated as seen below.\n\nHemoglobin: 10 g/dL\nHematocrit: 32%\nLeukocyte count: 9,500/mm^3 with normal differential\nPlatelet count: 199,000/mm^3\n\nSerum:\nNa+: 140 mEq/L\nCl-: 102 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 24 mEq/L\nBUN: 31 mg/dL\nGlucose: 100 mg/dL\nCreatinine: 1.6 mg/dL\nCa2+: 9.0 mg/dL\nPT: 40 seconds\naPTT: 90 seconds\nAST: 150 U/L\nALT: 90 U/L\n\nWhich of the following is the best description of this patient’s current status?", "answer": "Fulminant liver failure", "options": {"A": "Recovery from acute alcoholic liver disease", "B": "Recovery from ischemic liver disease", "C": "Recovery from acute renal failure", "D": "Acute renal failure", "E": "Fulminant liver failure"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 68-year-old man comes to the emergency department because of sudden onset abdominal pain for 6 hours. On a 10-point scale, he rates the pain as a 8 to 9. The abdominal pain is worst in the right upper quadrant. He has atrial fibrillation and hyperlipidemia. His temperature is 38.7° C (101.7°F), pulse is 110/min, and blood pressure is 146/86 mm Hg. The patient appears acutely ill. Physical examination shows a distended abdomen and tenderness to palpation in all quadrants with guarding, but no rebound. Murphy's sign is positive. Right upper quadrant ultrasound shows thickening of the gallbladder wall, sludging in the gallbladder, and pericolic fat stranding. He is admitted for acute cholecystitis and grants permission for cholecystectomy. His wife is his healthcare power of attorney (POA), but she is out of town on a business trip. He is accompanied today by his brother. After induction and anesthesia, the surgeon removes the gallbladder but also finds a portion of the small intestine is necrotic due to a large thromboembolism occluding a branch of the superior mesenteric artery. The treatment is additional surgery with small bowel resection and thromboendarterectomy. Which of the following is the most appropriate next step in management?", "answer": "Proceed with additional surgery without obtaining consent", "options": {"A": "Decrease the patient's sedation until he is able to give consent", "B": "Proceed with additional surgery without obtaining consent", "C": "Ask the patient's brother in the waiting room to consent", "D": "Contact the patient's healthcare POA to consent", "E": "Close the patient and obtain re-consent for a second operation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old woman, gravida 2, para 2, comes to the physician with intermenstrual bleeding and heavy menses for the past 4 months. She does not take any medications. Her father died of colon cancer at the age of 42 years. A curettage sample shows dysplastic tall, columnar, cells in the endometrium without intervening stroma. Germline sequencing shows a mutation in the MLH1 gene. Which of the following is the most likely underlying cause of neoplasia in this patient?", "answer": "Instability of short tandem DNA repeats", "options": {"A": "Accumulation of double-stranded DNA breaks", "B": "Defective checkpoint control transitions", "C": "Inability to excise bulky DNA adducts", "D": "Instability of short tandem DNA repeats", "E": "Impaired repair of deaminated DNA bases"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman presents with heavy menstrual bleeding between her periods. The patient also complains of experiencing an irregular menstrual cycle, weight loss, bloating, and constipation. She has had 3 uncomplicated pregnancies, all of which ended with normal vaginal deliveries at term. She has never taken oral contraception, and she does not take any medication at the time of presentation. She has no family history of any gynecological malignancy; however, her grandfather and mother had colon cancer that was diagnosed before they turned 50. On physical examination, the patient appears pale. Gynecological examination reveals a bloody cervical discharge and slight uterine enlargement. Endometrial biopsy reveals endometrial adenocarcinoma. Colonoscopy reveals several polyps located in the ascending colon, which are shown to be adenocarcinomas on histological evaluation. Which of the following mechanisms of DNA repair is likely to be disrupted in this patient?", "answer": "Mismatch repair", "options": {"A": "Nucleotide-excision repair", "B": "Base-excision repair", "C": "Mismatch repair", "D": "Homologous recombination", "E": "Non-homologous end joining"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 29-year-old woman comes to the clinic for complaints of fatigue and palpitations for the past 3 days. She reports that even standing up and walking around takes “a lot of energy.” She was forced to call in sick today to her work as a kindergarten teacher. She denies any previous episodes but does endorse symmetric joint pain of her hands, wrists, knees, and ankles that was worse in the morning over the past week that self-resolved. She also reports a runny nose and congestion. Past medical history is unremarkable. Physical examination demonstrates splenomegaly, pallor, and generalized weakness; there is no lymphadenopathy. What is the most likely explanation for this patient’s symptoms?", "answer": "Mutation of ankyrin", "options": {"A": "Anemia of chronic disease", "B": "Infection with Ebstein-Barr virus", "C": "Mutation of ankyrin", "D": "Rheumatoid arthritis", "E": "Substitution of glutamic acid with valine at the beta chain"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A research lab is investigating the rate of replication of a variety of human cells in order to better understand cancer metastasis. The cell shown in the image is of particular interest and is marked with a high concern for malignant potential. Which of the following is most closely associated with an increased potential for malignancy?", "answer": "Euchromatin", "options": {"A": "Euchromatin", "B": "Nucleosomes", "C": "Heterochromatin", "D": "H1 protein", "E": "Methylated DNA"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought in for evaluation by his adopted mother due to trouble starting 1st grade. His teacher has reported that he has been having trouble focussing on tasks and has been acting out while in class. His family history is unknown as he was adopted 2 years ago. His temperature is 36.2°C (97.2°F), pulse is 80/min, respirations are 20/min, and blood pressure 110/70 mm Hg. Visual inspection of the boy’s face shows a low set nasal bridge, a smooth philtrum, and small lower jaw. Which of the following findings would also likely be found on physical exam?", "answer": "Holosystolic murmur", "options": {"A": "Holosystolic murmur", "B": "Wide notched teeth", "C": "Limb hypoplasia", "D": "Cataracts", "E": "Congenital deafness"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 36-year-old woman with a past medical history of diabetes comes to the emergency department for abdominal pain. She reports that a long time ago her gynecologist told her that she had “some cysts in her ovaries but not to worry about it.” The pain started last night and has progressively gotten worse. Nothing seems to make it better or worse. She denies headache, dizziness, chest pain, dyspnea, diarrhea, or constipation; she endorses nausea, dysuria for the past 3 days, and chills. Her temperature is 100.7°F (38.2°C), blood pressure is 132/94 mmHg, pulse is 104/min, and respirations are 14/min. Physical examination is significant for right lower quadrant and flank pain with voluntary guarding. What is the most likely pathophysiology of this patient’s condition?", "answer": "Ascending infection of the urinary tract", "options": {"A": "Ascending infection of the urinary tract", "B": "Cessation of venous drainage from the ovaries", "C": "Inflammation of the appendix", "D": "Irritation of the peritoneal lining", "E": "Vesicoureteral reflex"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 71-year-old African American man diagnosed with high blood pressure presents to the outpatient clinic. In the clinic, his blood pressure is 161/88 mm Hg with a pulse of 88/min. He has had similar blood pressure measurements in the past, and you initiate captopril. He presents back shortly after initiation with extremely swollen lips, tongue, and face. After captopril is discontinued, what is the most appropriate step for the management of his high blood pressure?", "answer": "Initiate a thiazide diuretic", "options": {"A": "Reinitiate captopril", "B": "Switch to ramipril", "C": "Initiate an ARB ", "D": "Initiate a beta-blocker", "E": "Initiate a thiazide diuretic"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old white man presents to the emergency department because of progressive fatigue and shortness of breath on exertion and while lying down. He has had type 2 diabetes mellitus for 25 years and hypertension for 15 years. He is taking metformin and captopril for his diabetes and hypertension. He has smoked 10 cigarettes per day for the past 12 years and drinks alcohol occasionally. His temperature is 36.7°C (98.0°F) and blood pressure is 130/60 mm Hg. On physical examination, his arterial pulse shows a rapid rise and a quick collapse. An early diastolic murmur is audible over the left upper sternal border. Echocardiography shows severe chronic aortic regurgitation with a left ventricular ejection fraction of 55%–60% and mild left ventricular hypertrophy. Which of the following is an indication for aortic valve replacement in this patient?", "answer": "Presence of symptoms of left ventricular dysfunction", "options": {"A": "Old age", "B": "Long history of systemic hypertension", "C": "Presence of symptoms of left ventricular dysfunction", "D": "Long history of diabetes mellitus", "E": "Ejection fraction > 55%"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 50-year-old woman presents with a severe headache and vomiting. She says that symptoms onset after attending a wine tasting at the local brewery. She says that her headache is mostly at the back of her head and that she has been nauseous and vomited twice. Past medical history is significant for depression diagnosed 20 years ago but now well-controlled with medication. She also has significant vitamin D deficiency. Current medications are phenelzine and a vitamin D supplement. The patient denies any smoking history, alcohol or recreational drug use. On physical examination, the patient is diaphoretic. Her pupils are dilated. Which of the following is most likely to be elevated in this patient?", "answer": "Blood pressure", "options": {"A": "Serum creatinine", "B": "Temperature", "C": "Creatine phosphokinase", "D": "Blood pressure", "E": "Aspartate aminotransferase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man undergoes a parathyroidectomy given recurrent episodes of dehydration and kidney stones caused by hypercalcemia secondary to an elevated PTH level. He is recovering on the surgical floor on day 3. His temperature is 97.6°F (36.4°C), blood pressure is 122/81 mmHg, pulse is 84/min, respirations are 12/min, and oxygen saturation is 98% on room air. The patient is complaining of perioral numbness currently. What is the most appropriate management of this patient?", "answer": "Calcium gluconate", "options": {"A": "Calcium gluconate", "B": "Observation", "C": "Potassium", "D": "TSH level", "E": "Vitamin D"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 51-year-old woman comes to the physician because of daytime sleepiness and dry mouth for one month. She says her sleepiness is due to getting up to urinate several times each night. She noticed increased thirst about a month ago and now drinks up to 20 cups of water daily. She does not feel a sudden urge prior to urinating and has not had dysuria. She has a history of multiple urinary tract infections and head trauma following a suicide attempt 3 months ago. She has bipolar I disorder and hypertension. She has smoked one pack of cigarettes daily for 25 years. Examination shows poor skin turgor. Mucous membranes are dry. Expiratory wheezes are heard over both lung fields. There is no suprapubic tenderness. She describes her mood as “good” and her affect is appropriate. Neurologic examination shows tremor in both hands. Laboratory studies show a serum sodium of 151 mEq/L and an elevated antidiuretic hormone. Urine osmolality is 124 mOsm/kg H2O. Which of the following is the most likely explanation for this patient's symptoms?", "answer": "Mood stabilizer intake", "options": {"A": "Hypothalamic injury", "B": "Neuroleptic malignant syndrome", "C": "Paraneoplastic syndrome", "D": "Primary hyperaldosteronism", "E": "Mood stabilizer intake"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old man with hypertension and hyperlipidemia comes to the physician for a 4-month history of recurrent episodes of retrosternal chest pain, shortness of breath, dizziness, and nausea. The episodes usually start after physical activity and subside within minutes of resting. He has smoked one pack of cigarettes daily for 40 years. He is 176 cm (5 ft 9 in) tall and weighs 95 kg (209 lb); BMI is 30 kg/m2. His blood pressure is 160/100 mm Hg. Coronary angiography shows an atherosclerotic lesion with stenosis of the left anterior descending artery. Compared to normal healthy coronary arteries, increased levels of platelet-derived growth factor (PDGF) are found in this lesion. Which of the following is the most likely effect of this factor?", "answer": "Intimal migration of smooth muscles cells", "options": {"A": "Increased expression of vascular cell-adhesion molecules", "B": "Calcification of the atherosclerotic plaque core", "C": "Intimal migration of smooth muscles cells", "D": "Ingestion of cholesterol by mature monocytes", "E": "Invasion of T-cells through the disrupted endothelium"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old man presents with dry and brittle toenails for the past couple of years. Past medical history is significant for diabetes mellitus type 2, diagnosed 30 years ago, managed with metformin and sitagliptin daily. He is an office clerk and will be retiring next year. On physical examination, his toenails are shown in the image. Which of the following is an adverse effect of the recommended treatment for this patient’s most likely condition?", "answer": "Hepatitis", "options": {"A": "Chronic renal failure", "B": "Hypothyroidism", "C": "Chronic depression", "D": "Pancytopenia", "E": "Hepatitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 7-year-old boy is brought to the physician by his mother because of a limp for the last 3 weeks. He has also had right hip pain during this period. The pain is aggravated when he runs. He had a runny nose and fever around a month ago that resolved with over-the-counter medications. He has no history of serious illness. His development is adequate for his age. His immunizations are up-to-date. He appears healthy. He is at the 60th percentile for height and at 65th percentile for weight. Vital signs are within normal limits. Examination shows an antalgic gait. The right groin is tender to palpation. Internal rotation and abduction of the right hip is limited by pain. The remainder of the examination shows no abnormailities. His hemoglobin concentration is 11.6 g/dL, leukocyte count is 8,900/mm3, and platelet count is 130,000/mm3. An x-ray of the pelvis is shown. Which of the following is the most likely underlying mechanism?", "answer": "Avascular necrosis of the femoral head", "options": {"A": "Unstable proximal femoral growth plate", "B": "Bacterial infection of the joint", "C": "Viral infection", "D": "Immune-mediated synovial inflammation", "E": "Avascular necrosis of the femoral head"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old woman, gravida 2, para 1, comes for a prenatal visit at 33 weeks' gestation. She delivered her first child spontaneously at 38 weeks' gestation; pregnancy was complicated by oligohydramnios. She has no other history of serious illness. Her blood pressure is 100/70 mm Hg. On pelvic examination, uterine size is found to be smaller than expected for dates. The fetus is in a longitudinal lie, with vertex presentation. The fetal heart rate is 144/min. Ultrasonography shows an estimated fetal weight below the 10th percentile, and decreased amniotic fluid volume. Which of the following is the most appropriate next step in this patient?", "answer": "Serial nonstress tests", "options": {"A": "Reassurance only", "B": "Serial nonstress tests", "C": "Weekly fetal weight estimation", "D": "Amnioinfusion", "E": "Emergent cesarean delivery"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old newly immigrated mother arrives to the clinic to discuss breastfeeding options for her newborn child. Her medical history is unclear as she has recently arrived from Sub-Saharan Africa. You tell her that unfortunately she will not be able to breastfeed until further testing is performed. Which of the following infections is an absolute contraindication to breastfeeding?", "answer": "Human Immunodeficiency Virus (HIV)", "options": {"A": "Hepatitis B", "B": "Hepatitis C", "C": "Latent tuberculosis", "D": "Human Immunodeficiency Virus (HIV)", "E": "All of the above"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old man presents with a 1-week history of progressive diplopia followed by numbness and tingling in his hands and feet, some weakness in his extremities, and occasional difficulty swallowing. He was recently diagnosed with Hodgkin's lymphoma and started on a chemotherapeutic regimen that included bleomycin, doxorubicin, cyclophosphamide, vincristine, and prednisone. He denies fever, recent viral illness, or vaccination. On neurological examination, he has bilateral ptosis. His bilateral pupils are 5 mm in diameter and poorly responsive to light and accommodation. He has a bilateral facial weakness and his gag reflex is reduced. Motor examination using the Medical Research Council scale reveals a muscle strength of 4/5 in the proximal muscles of upper extremities bilaterally and 2/5 in distal muscles. In his lower extremities, hip muscles are mildly weak bilaterally, and he has bilateral foot drop. Deep tendon reflexes are absent. Sensory examination reveals a stocking-pattern loss to all sensory modalities in the lower extremities up to the middle of his shins. A brain MRI is normal. Lumbar puncture is unremarkable. His condition can be explained by a common adverse effect of which of the following drugs?", "answer": "Vincristine", "options": {"A": "Bleomycin", "B": "Cyclophosphamide", "C": "Doxorubicin", "D": "Prednisone", "E": "Vincristine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 72-year-old Caucasian woman presents with three months of progressive central vision loss accompanied by wavy distortions in her vision. She has hypertension controlled with metoprolol but has no other past medical history. Based on this clinical history she is treated with intravitreal injections of a medication. What is the mechanism of action of the treatment most likely used in this case?", "answer": "Inhibit choroidal neovascularization", "options": {"A": "Decrease ciliary body production of aqueous humor", "B": "Crosslink corneal collagen", "C": "Inhibit choroidal neovascularization", "D": "Pneumatic retinopexy", "E": "Increase outflow of aqueous humor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 19-year-old South Asian male presents to the family physician concerned that he is beginning to go bald. He is especially troubled because his father and grandfather \"went completely bald by the age of 25,\" and he is willing to try anything to prevent his hair loss. The family physician prescribes a medication that prevents the conversion of testosterone to dihydrotestosterone. Which of the following enzymes is inhibited by this medication?", "answer": "5-alpha-reductase", "options": {"A": "Desmolase", "B": "Aromatase", "C": "5-alpha-reductase", "D": "cGMP phosophodiesterase", "E": "Cyclooxygenase 2"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old woman presents to her primary care physician’s office complaining of right foot pain for the last week. She first noticed this pain when she awoke from bed one morning and describes it as deep at the bottom of her heel. The pain improved as she walked around her apartment but worsened as she attended ballet practice. The patient is a professional ballerina and frequently rehearses for up to 10 hours a day, and she is worried that this heel pain will prevent her from appearing in a new ballet next week. She has no past medical history and has a family history of sarcoidosis in her mother and type II diabetes in her father. She drinks two glasses of wine a week and smokes several cigarettes a day but denies illicit drug use. At this visit, the patient’s temperature is 98.6°F (37.0°C), blood pressure is 117/68 mmHg, pulse is 80/min, and respirations are 13/min. Examination of the right foot shows no overlying skin changes or swelling, but when the foot is dorsiflexed, there is marked tenderness to palpation of the bottom of the heel. The remainder of her exam is unremarkable. Which of the following is the best next step in management?", "answer": "Resting of the foot", "options": {"A": "Orthotic shoe inserts", "B": "Glucocorticoid injection", "C": "Plain radiograph of the foot", "D": "Resting of the foot", "E": "Ultrasound of the foot"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old man presents with acute onset of chest pain, trouble breathing, and abdominal pain. He says he had recently been training for a triathlon competition when, over the past week, he noticed that he was getting more tired than usual. He figured that it was due to his age since most of the people training with him were in their 20s. However, after completing a particularly difficult workout over this last weekend he noticed left-sided chest pain that did not radiate, and abdominal pain, worse on the right side. The pain persisted after he stopped exercising. This morning he noticed red urine. The patient reports similar past episodes of red urine after intense exercise or excessive alcohol intake for the past 5 years, but says it has never been accompanied by pain. Past medical history is significant for a urinary tract infection last week, treated with trimethoprim-sulfamethoxazole. Physical examination is significant for a systolic flow murmur loudest at the right upper sternal border and right upper quadrant tenderness without guarding or rebound. Laboratory findings are significant for the following:\nHemoglobin 8.5 g/dL\nPlatelets 133,000/µL\nTotal bilirubin 6.8 mg/dL\nLDH 740 U/L\nHaptoglobin 25 mg/dL\nAn abdominal MRI with contrast is performed which reveals hepatic vein thrombosis. Which of the following laboratory tests would most likely to confirm the diagnosis in this patient?", "answer": "Flow cytometry", "options": {"A": "Peripheral blood smear", "B": "Flow cytometry", "C": "Hemoglobin electrophoresis", "D": "Genetic testing", "E": "Sucrose hemolysis test"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old man comes to the physician because of a 3-week history of recurrent thumb pain that worsens with exposure to cold temperatures. Examination shows a 6-mm, blue-red papule under the left thumbnail. The overlying area is extremely tender to palpation. The thumbnail is slightly pitted and cracked. This lesion most likely developed from which of the following types of cells?", "answer": "Modified smooth muscle cells", "options": {"A": "Dysplastic melanocytes", "B": "Modified smooth muscle cells", "C": "Hyperpigmented fibroblasts", "D": "Injured nerve cells", "E": "Basal epidermal cells"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man presents to his primary care physician with a chief complaint of \"failing health.\" He states that he typically can converse with animals via telepathy, but is having trouble right now due to the weather. He has begun taking an assortment of Peruvian herbs to little avail. Otherwise he is not currently taking any medications. The patient lives alone and works in a health food store. He states that his symptoms have persisted for the past eight months. On physical exam, you note a healthy young man who is dressed in an all burlap ensemble. When you are obtaining the patient's medical history there are several times he is attempting to telepathically connect with the animals in the vicinity. Which of the following is the most likely diagnosis?", "answer": "Schizotypal personality disorder", "options": {"A": "Schizoid personality disorder", "B": "Schizotypal personality disorder", "C": "Schizophrenia", "D": "Schizophreniform disorder", "E": "Brief psychotic disorder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 18-month-old boy is brought in to the pediatrician by his mother for concerns that her child is becoming more and more yellow over the past two days. She additionally states that the boy has been getting over a stomach flu and has not been able to keep down any food. The boy does not have a history of neonatal jaundice. On exam, the patient appears slightly sluggish and jaundiced with icteric sclera. His temperature is 99.0°F (37.2°C), blood pressure is 88/56 mmHg, pulse is 110/min, and respirations are 22/min. His labs demonstrate an unconjugated hyperbilirubinemia of 16 mg/dL. It is determined that the best course of treatment for this patient is phenobarbital to increase liver enzyme synthesis. Which of the following best describes the molecular defect in this patient?", "answer": "Missense mutation in the UGT1A1 gene", "options": {"A": "Deletion in the SLCO1B1 gene", "B": "Silent mutation in the UGT1A1 gene", "C": "Mutation in the promoter region of the UGT1A1 gene", "D": "Missense mutation in the UGT1A1 gene", "E": "Nonsense mutation in the UGT1A1 gene"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 41-year-old G3P3 woman presents with acute on chronic right upper quadrant abdominal pain. She says that her current symptoms acutely onset 8 hours ago after eating a large meal and have not improved. She describes the pain as severe, sharp and cramping in character, and localized to the right upper quadrant. She also describes feeling nauseous. The patient says she has had similar less severe episodes intermittently for the past 2 years, usually precipitated by the intake of fatty foods. She denies any history of fever or jaundice. Vital signs are stable. Physical examination is unremarkable, and laboratory findings show normal liver function tests and normal serum bilirubin and serum amylase levels. Ultrasonography of the abdomen reveals multiple stones in the gallbladder. The patient is managed symptomatically for this episode, and after a few months, undergoes elective cholecystectomy, which reveals multiple stones in her gallbladder as shown in the figure (see image). Which of the following best describes these gallstones?", "answer": "They are formed due to bile supersaturated with cholesterol.", "options": {"A": "They are formed due to elevated uric acid in the blood.", "B": "They are formed due to the release of beta-glucuronidase from infecting bacteria.", "C": "These are usually radiopaque on X-ray imaging.", "D": "They are formed due to bile supersaturated with cholesterol.", "E": "These are seen in patients with chronic hemolysis."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old male is brought into the emergency department as the unrestrained passenger in a motor vehicle collision. On presentation he is obtunded with multiple ecchymoses on his chest and abdomen. There is marked distortion of his left lower extremity. His blood pressure is 90/64 mmHg, pulse is 130/min, and respirations are 24/min. Physical exam is limited by the patient’s mental state. The patient appears to be in pain while breathing and has tenderness to palpation of the abdomen. Neck veins are distended. Auscultation of the lungs reveals absent breath sounds on the left and hyperresonance to percussion. An emergent procedure is done and the patient improves. Had a chest radiograph of the patient been obtained on presentation to the ED, which of the following findings would most likely have been seen?", "answer": "Tracheal deviation to the right", "options": {"A": "Consolidation of the left lower lobe", "B": "Bilateral fluffy infiltrates at the lung bases", "C": "Collection of fluid in the left lung base", "D": "Tracheal deviation to the left", "E": "Tracheal deviation to the right"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old woman presents to the emergency department with chest pain, shortness of breath, and weakness. She has no known past medical history and generally refuses to see a physician for health issues. Review of systems is notable for chronic, severe gastroesophageal reflux disease and chronic diarrhea. Her temperature is 98.3°F (36.8°C), blood pressure is 177/105 mmHg, pulse is 88/min, respirations are 14/min, and oxygen saturation is 97% on room air. Laboratory values are ordered as seen below.\n\nHemoglobin: 10 g/dL\nHematocrit: 30%\nLeukocyte count: 4,500/mm^3 with normal differential\nPlatelet count: 192,400/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 101 mEq/L\nK+: 6.3 mEq/L\nBUN: 65 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 3.1 mg/dL\n\nNotably, the patient requires nursing to help her with most tasks such as putting on her gown and manipulating a cup of water given poor mobility of her hands. She also has recurrent episodes of severe hand pain, which self resolve. The patient is given calcium, insulin, and dextrose and started on dialysis. Which of the following is the most appropriate medical therapy for this patient?", "answer": "Captopril", "options": {"A": "Captopril", "B": "Furosemide", "C": "Hydrochlorothiazide", "D": "Labetalol", "E": "Nifedipine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 42-year-old woman presents to the emergency department in active labor. She has had no prenatal care and is unsure of the gestational age. Labor progresses rapidly and spontaneous vaginal delivery of a baby boy occurs 3 hours after presentation. On initial exam, the child is 1.9 kg (4.2 lb) with a small head and jaw. A sac-like structure containing intestine, as can be seen in the picture, protrudes from the abdominal wall. What complication is closely associated with this presentation?", "answer": "Cardiac defect", "options": {"A": "Duodenal atresia", "B": "Lack of abdominal wall muscles", "C": "Dehydration and necrosis of bowel", "D": "Cardiac defect", "E": "Twisting of the bowel around itself"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man presents to the emergency department with weakness and a fever for the past week. The patient is homeless and has a past medical history of alcohol and IV drug abuse. His temperature is 102°F (38.9°C), blood pressure is 107/68 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for a tremulous patient with antecubital scars and a murmur over the left lower sternal border. Blood cultures are drawn and the patient is started on vancomycin and ceftriaxone and is admitted to the ICU. The patient's fever and symptoms do not improve despite antibiotic therapy for which the initial identified organism is susceptible. Cultures currently reveal MRSA as one of the infective organisms. Which of the following is the best next step in management?", "answer": "Transesophageal echocardiography", "options": {"A": "CT scan of the chest", "B": "Nafcillin and piperacillin-tazobactam", "C": "Obtain new blood cultures", "D": "Transesophageal echocardiography", "E": "Vancomycin and gentamicin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old man presents to the his primary care physician complaining of an ongoing cough. He reports that the cough started 1 year ago after a “bad cold” and then never resolved. He feels the cough is getting worse, sometimes the cough is dry, but often the cough will bring up a clear to white mucus, especially in the morning. The patient has hypertension and peripheral artery disease. He takes aspirin and lisinopril. He started smoking at age 16, and now smokes 2 packs of cigarettes a day. He has 1-2 beers a couple nights of the week with dinner. He denies illicit drug use. Which of the following cell types within the lung is most likely to undergo metaplasia caused by smoking?", "answer": "Pseudostratified columnar", "options": {"A": "Pseudostratified columnar", "B": "Simple cuboidal", "C": "Simple squamous", "D": "Stratified squamous", "E": "Transitional"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 64-year-old woman presents to the emergency room with complaints of severe, whole-body itching. She states that she first noticed her symptoms while in the bathtub at home. She has never had symptoms like this before. However, over the previous several months she has had episodes of severe joint swelling and pain in her hands as well as redness, burning pain, and swelling of her hands and feet. Her past medical history is significant for type II diabetes mellitus, hypertension, and osteoporosis for which she takes metformin, enalapril, and alendronate, respectively. In addition, she was found to have a deep vein thrombosis of her left leg three months prior to presentation. The patient’s temperature is 98.6°F (37.0°C), pulse is 80/min, blood pressure is 135/85 mmHg, and respirations are 13/min. Physical exam is notable for a woman in discomfort with excoriations over the skin on her forearms. The patient’s laboratory tests are shown below.\n\nSerum:\nNa+: 135 mEq/L\nCl-: 100 mEq/L\nK+: 5.0 mEq/L\nHCO3-: 22 mEq/L\nBUN: 19 mg/dL\nGlucose: 130 mg/dL\nCreatinine: 1.0 mg/dL\n\nHematocrit: 64%\nLeukocyte count: 19,000 cells/mm^3 with normal differential\nPlatelet count: 900,000/mm^3\n\nWhat is the best next step in treatment of this patient's underlying condition?", "answer": "Hydroxyurea", "options": {"A": "Diphenhydramine", "B": "Hydroxyurea", "C": "Cyclophosphamide", "D": "Febuxostat", "E": "Prednisone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old woman, gravida 2, para 2, comes to the physician because of a 6-month history of heavy, irregular menstrual bleeding. Pelvic examination shows blood and clots in the posterior fornix and normal-appearing internal and external genitalia. An endometrial biopsy specimen shows straight uniform tubular glands lined with tall pseudostratified columnar epithelial cells with high mitotic activity embedded in an edematous stroma. Increased activity of which of the following is directly responsible for the histologic appearance of the biopsy specimen?", "answer": "Aromatase", "options": {"A": "Luteinizing hormone", "B": "Corpus luteum", "C": "5-alpha-reductase", "D": "Theca externa cells", "E": "Aromatase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2-year-old girl presents with high fever, restlessness, and a generalized papulovesicular rash. Past medical history is significant for varicella pneumonia and disseminated cytomegalovirus infection during the 1st year of her life. She was delivered vaginally to a primigravid 22-year-old woman from an uncomplicated pregnancy and was breastfed up to 9 months of age. She is up to date with her vaccines and is meeting all developmental milestones. The vital signs include blood pressure 70/45 mm Hg, heart rate 110/min, respiratory rate 27/min, and temperature 38.0°C (100.4°F). Physical examination demonstrates a generalized papulovesicular rash without a tendency to fuse. The rest of the physical examination is unremarkable for any pathological findings. Disseminated herpes virus infection is suspected. The child is also assessed for primary immunodeficiency. Flow cytometry reveals the absence of CD56 positive cells. Which of the following is true regarding these cells in this patient?", "answer": "They have cell surface receptors for detecting MHC 1 on other cells", "options": {"A": "They are the part of adaptive immunity", "B": "They have cell surface receptors for detecting MHC 1 on other cells", "C": "They need MHC class 1 to be expressed on the cell to eliminate it", "D": "They differentiate from the myeloid progenitor", "E": "These cells also express the T cell receptor"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-year-old male child presents to the emergency department with a fever, dry cough, and shortness of breath. The condition began approximately 5 days ago with a rise in body temperature up to 38.7°C (101.7℉), headache, myalgias, and runny nose. Three days after the onset, the patient started to develop a non-productive cough and later, dyspnea. His vital signs are as follows: blood pressure is 100/70 mm Hg, heart rate is 91/min, respiratory rate is 29/min, and temperature is 38.1℃ (100.6℉). On examination, his oxygen saturation is 88%. The patient has a mild pharyngeal erythema and cervical lymphadenopathy. Lung auscultation shows no remarkable findings. Chest radiograph shows patchy reticular opacities best visualized in the perihilar region. A sputum culture is positive for Mycoplasma pneumoniae. Which of the following is consistent with the patient’s condition?", "answer": "Increased A-a gradient, increased diffusion distance", "options": {"A": "Normal A-a gradient, increased diffusion distance", "B": "Decreased A-a gradient, increased diffusion distance", "C": "Decreased A-a gradient, decreased diffusion distance", "D": "Increased A-a gradient, increased diffusion distance", "E": "Increased A-a gradient, decreased diffusion distance"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 49-year-old man comes to the physician for evaluation of several painless, pruritic lesions on his left forearm that he first noticed 4 days ago. They were initially pink marks that progressed into blisters before ulcerating. He has also had a headache for 1 week. His temperature is 38.1°C (100.6°F). A photograph of one of the lesions is shown. There is pronounced edema of the surrounding skin and painless swelling of the left axillary lymph nodes. Which of the following is the greatest risk factor for this patient's condition?", "answer": "Wool handling", "options": {"A": "Pool swimming", "B": "Cat scratch", "C": "Wool handling", "D": "Sexual contact", "E": "Spider bite"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 76-year-old woman comes in for a routine checkup with her doctor. She is concerned that she feels tired most days and has difficulty doing her household chores. She complains that she gets fatigued and breathless with mild exertion. Past medical history is significant for diabetes mellitus, chronic kidney disease from prolonged elevated blood sugar, and primary biliary cirrhosis. Medications include lisinopril, insulin, and metformin. Family medicine is noncontributory. She drinks one beer every day. Today, she has a heart rate of 98/min, respiratory rate of 17/min, blood pressure of 110/65 mm Hg, and a temperature of 37.0°C (98.6°F). General examination shows that she is pale and haggard looking. She has a heartbeat with a regular rate and rhythm and her lungs are clear to auscultation bilaterally. A complete blood count (CBC) is as follows:\nLeukocyte count: 12,000/mm3\nRed blood cell count: 3.1 million/mm3\nHemoglobin: 11.0 g/dL\nMCV: 85 um3\nMCH: 27 pg/cell\nPlatelet count: 450,000/mm3\nFecal occult blood test is negative. What is the most likely cause of her anemia?", "answer": "Chronic kidney disease", "options": {"A": "Chronic kidney disease", "B": "Acute bleeding", "C": "Alcoholism", "D": "Liver disease", "E": "Colorectal cancer"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 23-year-old Caucasian G2P1 presents for a routine prenatal care visit at 25 weeks gestation. She has no complaints and the pregnancy has been uncomplicated thus far. The previous pregnancy was complicated by pre-eclampsia and she delivered a small-for-gestational-age girl at 36 weeks gestation. The pre-pregnancy weight was 73 kg (161 lb), and she now weighs 78 kg (172 lb). Her height is 155 cm. The blood pressure is 120/80 mm Hg, the heart rate is 91/min, the respiratory rate is 14/min, and the temperature is 36.7℃ (98℉). Her physical examination is normal and the gynecologic examination corresponds to 25 weeks gestation. An oral glucose tolerance test (OGTT) with a 75-g glucose load was abnormal with a 1-h glucose level of 189 mg/dL. Which of the following is a risk factor for the patient’s condition?", "answer": "re-pregnancy BMI", "options": {"A": "Patient age", "B": "Patient ethnicity", "C": "re-pregnancy BMI", "D": "History of pre-eclampsia", "E": "History of birth of a small-for-gestational-age baby"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 78-year-old woman comes to the physician because of a 2-month history of right-sided headache and generalized fatigue. She also has pain, weakness, and stiffness of her shoulders and hips. The stiffness is worse in the morning and usually improves after 60–90 minutes of activity. Three months ago, she fell and hit her head on the kitchen countertop. Her temperature is 38.1°C (100.6°F). Examination shows normal muscle strength in bilateral upper and lower extremities; range of motion of the shoulder and hip is mildly limited by pain. Deep tendon reflexes are 2+ bilaterally. Her erythrocyte sedimentation rate is 68 mm/h and serum creatine kinase is 36 mg/dL. Which of the following is the most likely underlying cause of this patient's headache?", "answer": "Large-vessel vasculitis", "options": {"A": "Tension headache", "B": "Large-vessel vasculitis", "C": "Polyarteritis nodosa", "D": "Hyperthyroidism", "E": "Cluster headache"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Three days after delivery, a 4000-g (8.8-lb) male newborn has several episodes of right-sided arm and leg twitching and lip smacking. These shaking episodes have occurred about six times over the last hour and have lasted for about 40 seconds. He has also had rapid breathing and poor feeding. He has not had fever or trauma. He was born at 37 weeks' gestation. Pregnancy and delivery were uncomplicated. There is no family history of serious illness. His temperature is 37°C (98.6°F), pulse is 230/min, and respirations are 70/min. He appears irritable and jittery. There are intermittent spasms present. The remainder of the examination shows no abnormalities. Laboratory studies show a serum calcium concentration of 6 mg/dL and a serum parathyroid hormone concentration of 150 pg/mL. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Maternal familial hypocalciuric hypercalcemia", "options": {"A": "Maternal familial hypocalciuric hypercalcemia", "B": "Neonatal ingestion of formula with high phosphate load", "C": "Neonatal hypoglycemia", "D": "Increased neonatal thyroid hormone secretion", "E": "Maternal opioid abuse during pregnancy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old man presents with a nodule on his right foot. He says that he first noticed the nodule last week. It has not undergone any change in size and color. He denies any history of trauma or fever. Past medical history is significant for HIV, diagnosed 6 years ago. He is currently not on antiretroviral therapy. His last CD4+ T cell count was 0.19 x 109/L. He is afebrile, and his vital signs are within normal limits. On physical examination, there is a 3 cm x 4 cm nodule on the right foot, tan brown in color, non-tender, and covered with a fine scale. A biopsy of the nodule is performed and histopathological analysis reveals the proliferation of blood vessels with overgrown endothelial cells. Histological staining of the biopsy tissue reveals gram-negative bacilli. Which of the following is the best course of treatment for this patient?", "answer": "Erythromycin", "options": {"A": "Cefazolin", "B": "Penicillin", "C": "Vancomycin", "D": "Erythromycin", "E": "Interferon-α"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old boy is brought to the physician by his father because of a 7-month history of fatigue, recurrent leg cramps, and increased urinary frequency. His pulse is 94/min and blood pressure is 118/85 mm Hg. Physical examination shows dry mucous membranes. Laboratory studies show:\nSerum\nNa+ 130 mEq/L\nK+ 2.8 mEq/L\nCl- 92 mEq/L\nMg2+ 1.1 mEq/L\nCa2+ 10.6 mg/dL\nAlbumin 5.2 g/dL\nUrine\nCa2+ 70 mg/24 h\nCl- 375 mEq/24h (N = 110–250)\nArterial blood gas analysis on room air shows a pH of 7.55 and an HCO3- concentration of 45 mEq/L. Impaired function of which of the following structures is the most likely cause of this patient's condition?\"", "answer": "Distal convoluted tubule", "options": {"A": "Ascending loop of Henle", "B": "Distal convoluted tubule", "C": "Descending loop of Henle", "D": "Collecting duct", "E": "Proximal convoluted tubule"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 66-year-old male presents to the emergency room with shortness of breath with exertion and at rest for the past 5 days. His shortness of breath is mostly at night, and he is also concerned about bilateral leg swelling. He is a heart failure patient who is being managed with oral medication and has been compliant with his drugs. Physical examination reveals an elderly man in respiratory distress with abdominal distention and bilateral pitting ankle edema. Respiratory rate is 32/min, SpO2 is 93% in room air, and coarse crepitations are heard on both lung bases. Pulse rate is 73/min and barely palpable. His blood pressure is 79/54 mm Hg. On auscultation, a blowing holosystolic murmur is heard at the apex radiating to the left axilla. An echocardiography shows an ejection fraction of 18%. The physician decides to include an inotropic agent in his current medication. What would likely result from this intervention?", "answer": "A decrease in the interval between the heart sounds S1 and S2", "options": {"A": "A decrease in the systemic vascular resistance", "B": "A decrease in the interval between the heart sounds S1 and S2", "C": "An increase in the left ventricular end-systolic volume", "D": "A decrease in the interval between the heart sounds S2 and S1", "E": "A decrease in the left ventricular end-diastolic pressure"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A geriatric investigator is evaluating the consistency of Alzheimer dementia diagnoses based on clinical symptoms. Patients with known chart diagnoses of Alzheimer dementia were evaluated by multiple physicians during a fixed time interval. Each evaluator was blinded to the others' assessments. The extent to which the diagnosis by one physician was replicated by another clinician examining the same patient is best described by which of the following terms?", "answer": "Precision", "options": {"A": "Validity", "B": "Specificity", "C": "Predictive value", "D": "Precision", "E": "Sensitivity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old woman presents with irregular menstrual cycles for the past 3 years and facial acne. Patient says she had menarche at the age of 11, established a regular cycle at 13, and had regular menses until the age of 16. Patient is sexually active with a single partner, and they use barrier contraception. They currently do not plan to get pregnant. There is no significant past medical history and she takes no current medications. Vitals are temperature 37.0℃ (98.6℉), blood pressure 125/85 mm Hg, pulse 69/min, respiratory rate 14/min, and oxygen saturation 99% on room air. Physical examination is significant for multiple comedones on her face. She also has hair on her upper lip, between her breasts, along with the abdominal midline, and on her forearms. There is hyperpigmentation of the axillary folds and near the nape of the neck. Laboratory tests are significant for the following:\nSodium   141 mEq/L\nPotassium   4.1 mEq/L\nChloride  101 mEq/L\nBicarbonate  25 mEq/L\nBUN  12 mg/dL\nCreatinine  1.0 mg/dL\nGlucose (fasting)   131 mg/dL \n  Bilirubin, conjugated 0.2 mg/dL\nBilirubin, total   1.0 mg/dL\nAST (SGOT)    11 U/L\nALT (SGPT)        12 U/L\nAlkaline Phosphatase 45 U/L\n  WBC  6,500/mm3\nRBC 4.80 x 106/mm3 \nHematocrit  40.5%\nHemoglobin  14.0 g/dL\nPlatelet Count   215,000/mm3\n  TSH    4.4 μU/mL   \nFSH   73 mIU/mL\nLH   210 mIU/mL\nTestosterone, total  129 ng/dL (ref: 6-86 ng/dL)\nβ-hCG  1 mIU/mL\nWhich of the following is the best course of treatment for this patient?", "answer": "Oral contraceptives", "options": {"A": "Finasteride", "B": "Oral contraceptives", "C": "Clomiphene", "D": "Goserelin", "E": "Letrozole"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 41-year-old man presents to the office with pain in his right big toe. The pain started yesterday and has been progressively getting worse to the point that it is difficult to walk. He describes his right big toe as being swollen and hot to the touch. He has never had symptoms like this before. He drinks 3 beers per night. Medical history is otherwise significant for chronic kidney disease. Physical examination is notable for an overweight gentleman in moderate pain, with an erythematous, swollen and tender right toe. He is afebrile. A joint fluid analysis in this patient is most likely to show what?", "answer": "Negatively birefringent crystals", "options": {"A": "Gram negative diplococci", "B": "Negatively birefringent crystals", "C": "Positively birefringent crystals", "D": "Glucose < 40 mg/dL", "E": "Normal"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old man comes to the clinic complaining of intermittent abdominal pain for the past 2 months. He reports that the pain improves with oral intake and is concentrated at the epigastric area. The pain is described as gnawing in quality and improves when he takes his wife’s ranitidine. He denies weight changes, fever, chest pain, or recent travel but endorses “brain fog” and decreased libido. An upper endoscopy reveals ulcerations at the duodenum and jejunum. Physical examination demonstrates bilateral hemianopsia, gynecomastia, and diffuse pain upon palpation at the epigastric area. Laboratory findings are demonstrated below:\n\nSerum:\nNa+: 137 mEq/dL\nCl-: 96 mEq/L\nK+: 3.9 mEq/dL\nHCO3-: 25 mEq/L\nGlucose: 110 mg/dL\nCreatinine: .7 mg/dL\nCa2+: 13.5 mg/dL\n\nWhat is the best explanation for this patient’s findings?", "answer": "Mutation of the MEN1 gene", "options": {"A": "Gastrin secreting tumor of the pancreas", "B": "Infection with Helicobacter pylori", "C": "Mutation of the APC gene", "D": "Mutation of the MEN1 gene", "E": "Mutation of the RET gene"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2980-g (6.6-lb) female newborn is brought to the emergency department by her mother because of worsening lethargy. The newborn was delivered at home 10 hours ago. The mother has had no prenatal care. The newborn's temperature is 39.7°C (103.5°F). Physical examination shows scleral icterus. Her leukocyte count is 36,000/mm3 (85% segmented neutrophils). An organism is isolated from the blood. When grown together on sheep agar, the isolated organism enlarges the area of clear hemolysis formed by Staphylococcus aureus. Which of the following is the most likely causal organism?", "answer": "Streptococcus agalactiae", "options": {"A": "Pseudomonas aeruginosa", "B": "Listeria monocytogenes", "C": "Streptococcus pyogenes", "D": "Streptocccus pneumoniae", "E": "Streptococcus agalactiae"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 75-year-old man is brought to the emergency room after being found unconscious in his home. His medical history is unknown. On physical examination he does not demonstrate any spontaneous movement of his extremities and is unable to respond to voice or painful stimuli. You notice that he is able blink and move his eyes in the vertical plane. Based on these physical exam findings, you expect that magnetic resonance angiogram will most likely reveal an occlusion in which of the following vessels?", "answer": "Basilar artery", "options": {"A": "Anterior cerebral artery", "B": "Anterior spinal artery", "C": "Anterior inferior cerebellar artery", "D": "Basilar artery", "E": "Posterior cerebral artery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old man presents to an urgent care center with epigastric discomfort following meals and an occasional dry cough worse in the morning, both of which have increased in frequency over the past several months. He is otherwise healthy and has no additional complaints. Past medical history is significant for major depressive disorder, anxiety, and hypothyroidism. Physical examination is unremarkable. His vital signs include temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. Given the following options, what is the most appropriate next step in patient management?", "answer": "Lifestyle modifications", "options": {"A": "Electrocardiography (ECG)", "B": "Lifestyle modifications", "C": "Begin omeprazole therapy", "D": "Esophagogastroduodenoscopy (EGD) with esophageal biopsy", "E": "Fluoroscopic barium swallow"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old gravida 3 para 1 is admitted to labor and delivery with uterine contractions. She is at 37 weeks gestation with no primary care provider or prenatal care. She gives birth to a boy after an uncomplicated vaginal delivery with APGAR scores of 7 at 1 minute and 8 at 5 minutes. His weight is 2.2 kg (4.4 lb) and the length is 48 cm (1.6 ft). The infant has weak extremities and poor reflexes. The physical examination reveals microcephaly, palpebral fissures, thin lips, and a smooth philtrum. A systolic murmur is heard on auscultation. Identification of which of the following factors early in the pregnancy could prevent this condition?", "answer": "Alcohol consumption", "options": {"A": "Phenytoin usage", "B": "Alcohol consumption", "C": "Maternal toxoplasmosis", "D": "Physical abuse", "E": "Maternal hypothyroidism"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old boy is brought to the physician because of a rash and difficulty swallowing. His family emigrated from Nigeria 2 months ago. Examination shows an erythematous rash with fine yellow scales on his eyebrows and nasolabial folds. Oral examination shows an erythematous throat and swollen tongue. There is peeling and fissures of the skin at the corners of the mouth and cracking of the lips. His hemoglobin concentration is 9.6 g/dL; mean corpuscular volume is 89 μm3. Erythrocyte glutathione reductase assay shows an increased activity coefficient. This patient is most likely deficient in a vitamin that is a precursor to which of the following molecules?", "answer": "Flavin adenine dinucleotide", "options": {"A": "Thiamine pyrophosphate", "B": "Flavin adenine dinucleotide", "C": "Nicotinamide adenine dinucleotide", "D": "Methylcobalamin", "E": "Pyridoxal phosphate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old girl presents with primary amenorrhea. On exam, you note that she is short and has a shield chest. You order abdominal imaging, which suggests the presence of streak gonads.\n\nOf the choices listed below, which of the following karyotypes is possible in this patient?\n\nI: 45, XO\nII: 45XO/46XX mosaicism\nIII: 46XX with partial deletion", "answer": "I, II, and III", "options": {"A": "I only", "B": "I and II", "C": "I and III", "D": "I, II, and III", "E": "II and III"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 62-year-old man seeks evaluation at an outpatient clinic for a single, red, crusty lesion on the shaft of his penis and a similar lesion on the middle finger of his left hand. He recently immigrated to the US from Africa. The lesions are painless and the physicians in his country treated him for syphilis and eczema, with no improvement. He lives with his 4th wife. He smokes 2 packs of cigarette per day and has been doing so for the last 30 years. He is not aware of any family members with malignancies or hereditary diseases. The physical examination is remarkable for an erythematous plaque, with areas of crusting, oozing, and irregular borders on the dorsal surface of the penile shaft and a similar lesion on his left middle finger (shown in the picture). The regional lymph nodes are not affected. A biopsy is obtained and the pathologic evaluation reveals cells with nuclear hyperchromasia, multinucleation, and increased mitotic figures within the follicle-bearing epithelium. What is the most likely diagnosis?", "answer": "Bowen's disease", "options": {"A": "Condyloma acuminata", "B": "Bowenoid papulosis", "C": "Lichen sclerosus", "D": "Bowen's disease", "E": "Erythroplasia of Queyrat"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 36-year-old male suffered a gun-shot wound to the abdomen that required an emergent exploratory laparotomy to repair and resect damaged portions of the bowel. Four days later, the patient reports increased generalized abdominal pain. His vital signs are as follows: T 38.5, HR 110, BP 110/60, RR 18, SpO2 96%. Physical exam reveals extreme tenderness to palpation of the abdomen as well as rebound tenderness, worse in the bilateral lower quadrants. The abdomen is mildly distended with guarding and decreased bowel sounds. The surgical and bullet-entrance wounds appear intact without any evidence of leakage/drainage, erythema, or warmth. Initial lab-work shows an elevated white blood cell count of 17.1 x 10^9 cells/L. A CT scan of the abdomen shows a 4 cm abscess in the left lower quadrant. Which of the following organisms is the most likely cause of this patient's current presentation?", "answer": "Bacteroides fragilis", "options": {"A": "Pseudomonas aeruginosa", "B": "Salmonella enteritidis", "C": "Bacteroides fragilis", "D": "Enterococcus species", "E": "Streptococcus bovis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A parent-teacher conference is called to discuss the behavior of a 9 year-old boy. According to the boy's teacher, he has become progressively more disruptive during class. When asked to help clean up or read out-loud, he replies with \"You're not the boss of me.\" or \"You can't make me.\" He refuses to participate in gym class, but will play the same games during recess. He gets along with and is well-liked by his peers. His mother reports that her son can \"sometimes be difficult,\" but he is helpful around the house and is very good playing with his 7-year-old sister. What is the most likely diagnosis?", "answer": "Oppositional defiant disorder", "options": {"A": "Conduct disorder", "B": "Oppositional defiant disorder", "C": "Antisocial personality disorder", "D": "Attention deficit disorder", "E": "Separation anxiety disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old African American man presents to his primary care physician’s office for an annual visit. He has no major concerns and says that he has been healthy for the last year. His past medical history is significant for diabetes as well as long standing hypertension that has developed gradually since his 30's; however, he has refused to take any medications. Physical exam shows no abnormal findings. Routine laboratory testing reveals the following:\n\nSerum creatinine concentration: 1.5 mg/dL\nBlood urea nitrogen: 31 mg/dL\n\nBased on these results, urine studies are conducted that reveal mild proteinuria of less than 1 g/day and no casts.\n\nWhich of the following is most likely associated with the cause of this patient's elevated creatinine?", "answer": "Cobblestone kidney", "options": {"A": "Apple-green birefringent lesions", "B": "Cobblestone kidney", "C": "Kimmelstiel-Wilson lesions", "D": "Renal cortex necrosis", "E": "String of beads on angiography"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 38-year-old woman comes to the physician because of an 8-week history of shortness of breath and dull chest pain. She has a history of antiphospholipid syndrome. Physical examination shows jugular venous distention. Right heart catheterization shows a mean pulmonary arterial pressure of 30 mm Hg and a pulmonary capillary wedge pressure of 10 mm Hg. Further evaluation is most likely to show which of the following?", "answer": "Dilation of the coronary sinus", "options": {"A": "Constriction of the renal afferent arteriole", "B": "Dilation of the coronary sinus", "C": "Decreased left ventricular contractility", "D": "Mitral valve leaflet thickening", "E": "Hemosiderin-laden macrophages\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A neonate born at 33 weeks is transferred to the NICU after a complicated pregnancy and C-section. A week after being admitted, he developed a fever and become lethargic and minimally responsive to stimuli. A lumbar puncture is performed that reveals the following:\nAppearance  Cloudy\nProtein 64 mg/dL\nGlucose 22 mg/dL\nPressure 330 mm H20\nCells 295 cells/mm³ (> 90% PMN)\nA specimen is sent to microbiology and reveals gram-negative rods. Which of the following is the next appropriate step in management?", "answer": "Start the patient on IV cefotaxime", "options": {"A": "Provide supportive measures only", "B": "MRI scan of the head", "C": "Start the patient on IV ceftriaxone", "D": "Start the patient on IV cefotaxime", "E": "Start the patient on oral rifampin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 19-year-old woman presents to the dermatology clinic for a follow-up of worsening acne. She has previously tried topical tretinoin as well as topical and oral antibiotics with no improvement. She recently moved to the area for college and says the acne has caused significant emotional distress when it comes to making new friends. She has no significant past medical or surgical history. Family and social history are also noncontributory. The patient’s blood pressure is 118/77 mm Hg, the pulse is 76/min, the respiratory rate is 17/min, and the temperature is 36.6°C (97.9°F). Physical examination reveals erythematous skin lesions including both open and closed comedones with inflammatory lesions overlying her face, neck, and upper back. The patient asks about oral isotretinoin. Which of the following is the most important step in counseling this patient prior to prescribing oral isotretinoin?", "answer": "Document 2 negative urine or blood pregnancy tests before beginning oral isotretinoin", "options": {"A": "Avoid direct sunlight, from 10am to 2pm", "B": "Wear a wide-brimmed hat outdoors", "C": "Use non-comedogenic sunscreen daily with SPF of at least 45", "D": "Document 2 negative urine or blood pregnancy tests before beginning oral isotretinoin", "E": "Apply topical retinoids in the evening before bed"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old man comes to the physician for a routine examination. He feels well. His pulse is 80/min and blood pressure is 140/85 mm Hg. Cardiac examination shows a holosystolic murmur in the 4th intercostal space along the left sternal border that gets louder during inspiration. The increase of this patient's murmur is best explained by which of the following hemodynamic changes?", "answer": "Increased right ventricular stroke volume", "options": {"A": "Increased peripheral vascular resistance", "B": "Increased right ventricular stroke volume", "C": "Decreased pulmonary vessel capacity", "D": "Decreased left ventricular venous return", "E": "Increased systemic venous compliance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-year-old boy presents with a dry cough. The patient’s mother states that the cough started a week ago and has not improved. She says the patient will have fits of forceful coughing that will last for minutes, followed by gasping as he catches his breath. Occasionally, the patient will vomit after one of these episodes. Past medical history is significant for a recent upper respiratory infection 4 weeks ago that has resolved. No current medications. Patient immunization status is incomplete because his mother believes they are harmful. Vitals are temperature 37.0°C (98.6°F), blood pressure 105/65 mm Hg, pulse 101/min, respiratory rate 27/min, and oxygen saturation 99% on room air. Cardiac exam is normal. Lungs are clear to auscultation. There are conjunctival hemorrhages present bilaterally. Which of the following correctly describes the stage of this patient’s most likely diagnosis?", "answer": "Paroxysmal stage", "options": {"A": "Catarrhal stage", "B": "Paroxysmal stage", "C": "Convalescent stage", "D": "Intermittent stage", "E": "Persistent stage"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old primigravid woman is brought to the emergency department after complaining of severe abdominal pain for 3 hours. She has had no prenatal care. There is no leakage of amniotic fluid. Since arrival, she has had 5 contractions in 10 minutes, each lasting 70 to 90 seconds. Pelvic examination shows a closed cervix and a uterus consistent in size with a 38-week gestation. Ultrasound shows a single live intrauterine fetus in a breech presentation consistent with a gestational age of approximately 37 weeks. The amniotic fluid index is 26 and the fetal heart rate is 92/min. The placenta is not detached. She is scheduled for an emergency lower segment transverse cesarean section because of a nonreassuring fetal heart rate. The infant is delivered and APGAR score is noted to be 8 at 1 minute. The doctor soon notices cyanosis of the lips and oral mucosa, which does not resolve when the infant cries. The infant is foaming at the mouth and drooling. He also has an intractable cough. Which of the following is the most likely diagnosis?", "answer": "Esophageal atresia", "options": {"A": "Esophageal atresia", "B": "Esophageal stricture", "C": "Achalasia", "D": "Pulmonary hypoplasia", "E": "Defective swallowing reflex"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 16 year-old female is being evaluated for shortness of breath. For the last year she has had shortness of breath and subjective wheezing with exercise and intermittent coughing at night. She reports waking up from sleep coughing 1-2 times per month. She now skips gym class because of her symptoms. She denies any coughing, chest tightness, or shortness of breath on the day of her visit. On exam, her lungs are clear to auscultation bilaterally, with normal inspiratory to expiratory duration ratio. Her pulmonary function tests (PFTs) show normal FEV1 and FVC based on her age, gender, and height. She is told to inhale a medication, and her PFTs are repeated, now showing a FEV1 79% of her previous reading. The patient is diagnosed with asthma. Which of the following medications was used to diagnose the patient?", "answer": "Methacholine", "options": {"A": "Methacholine", "B": "Pilocarpine", "C": "Bethanechol", "D": "Carbachol", "E": "Physostigmine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old man is admitted to the hospital for treatment of burn wounds on his upper extremities. Analgesic therapy with an opioid drug is begun. Shortly after, the patient develops chills, diaphoresis, nausea, and abdominal pain. On further questioning, the patient reports that he has been smoking opium at home to help him \"\"deal with the depression and pain.” This patient was most likely given which of the following opioid drugs?\"", "answer": "Butorphanol", "options": {"A": "Morphine", "B": "Hydrocodone", "C": "Fentanyl", "D": "Oxycodone", "E": "Butorphanol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man comes to the physician because of heartburn for the past 2 years. He has no chest pain, dysphagia, weight loss, or fever. He has no history of any serious illnesses. He takes omeprazole daily. Vital signs are within normal limits. Body mass index (BMI) is 34 kg/m2. Physical exam shows no abnormalities. An endoscopic image of the lower esophageal sphincter is shown. Which of the following is the most important next step in management?", "answer": "Multiple endoscopic biopsies", "options": {"A": "Endoscopic mucosal ablation therapy", "B": "Esophagectomy", "C": "High-dose pantoprazole", "D": "Laparoscopic Nissen fundoplication", "E": "Multiple endoscopic biopsies"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old male is brought into the emergency department by emergency medical services. The patient has a history of bipolar disease complicated by polysubstance use. He was found down in his apartment at the bottom of a staircase lying on his left arm. He was last seen several hours earlier by his roommate. He is disoriented and unable to answer any questions, but is breathing on his own. His vitals are HR 55, T 96.5, RR 18, BP 110/75. You decide to obtain an EKG as shown in Figure 1. What is the next best step in the treatment of this patient?", "answer": "Calcium gluconate", "options": {"A": "Intubation", "B": "Epinephrine", "C": "Albuterol", "D": "Insulin", "E": "Calcium gluconate"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old woman is brought to the emergency department because of a 1-day history of double vision and rapidly worsening pain and swelling of her right eye. She had an upper respiratory tract infection a week ago after which she has had nasal congestion, recurrent headaches, and a purulent nasal discharge. She took antibiotics for her respiratory tract infection but did not complete the course. She has asthma treated with theophylline and inhaled β-adrenergic agonists and corticosteroids. She appears to be in severe distress. Her temperature is 38.5°C (101.3°F), pulse is 100/min, and blood pressure is 130/80 mm Hg. Ophthalmic examination of the right eye shows proptosis and diffuse edema, erythema, and tenderness of the eyelids. Right eye movements are restricted and painful in all directions. The pupils are equal and reactive to light. There is tenderness to palpation over the right cheek and purulent nasal discharge in the right nasal cavity. The left eye shows no abnormalities. Laboratory studies show a leukocyte count of 12,000/mm3. Which of the following provides the strongest indication for administering intravenous antibiotics to this patient?", "answer": "Pain with eye movements", "options": {"A": "Worsening of ocular pain", "B": "Leukocytosis", "C": "Pain with eye movements", "D": "Purulent nasal discharge and right cheek tenderness", "E": "Fever\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man with a 60 pack-year smoking history is referred by his primary care physician for a pulmonary function test (PFT). A previously obtained chest x-ray is shown below. Which of the following will most likely appear in his PFT report?", "answer": "Residual volume increased, total lung capacity increased", "options": {"A": "Residual volume increased, total lung capacity decreased", "B": "Residual volume increased, total lung capacity increased", "C": "Residual volume decreased, total lung capacity increased", "D": "Residual volume normal, total lung capacity normal", "E": "Residual volume normal, total lung capacity decreased"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Fourteen days after a laparoscopic cholecystectomy for cholelithiasis, a 45-year-old woman comes to the emergency department because of persistent episodic epigastric pain for 3 days. The pain radiates to her back, occurs randomly throughout the day, and is associated with nausea and vomiting. Each episode lasts 30 minutes to one hour. Antacids do not improve her symptoms. She has hypertension and fibromyalgia. She has smoked 1–2 packs of cigarettes daily for the past 10 years and drinks 4 cans of beer every week. She takes lisinopril and pregabalin. She appears uncomfortable. Her temperature is 37°C (98.6° F), pulse is 84/min, respirations are 14/min, and blood pressure is 127/85 mm Hg. Abdominal examination shows tenderness to palpation in the upper quadrants without rebound or guarding. Bowel sounds are normal. The incisions are clean, dry, and intact. Serum studies show:\nAST 80 U/L\nALT 95 U/L\nAlkaline phosphatase 213 U/L\nBilirubin, total 1.3 mg/dL\nDirect 0.7 mg/dL\nAmylase 52 U/L\nAbdominal ultrasonography shows dilation of the common bile duct and no gallstones. Which of the following is the most appropriate next step in management?\"", "answer": "Endoscopic retrograde cholangiopancreatography", "options": {"A": "Counseling on alcohol cessation", "B": "Endoscopic retrograde cholangiopancreatography", "C": "Proton pump inhibitor therapy", "D": "Reassurance and follow-up in 4 weeks", "E": "CT scan of the abdomen"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 53-year-old woman presents to the office complaining of an extreme, nonradiating stabbing pain in the epigastric region after having a meal. She states that it has happened several times in the past week approximately 30 minutes after eating and spontaneously resolves. A day before, the patient went to urgent care with the same complaint, but the abdominal X-ray was normal. Surgical history is remarkable for a total knee arthroplasty procedure 6 months ago. She has lost 34 kg (75 lb) since the operation because of lifestyle changes. The vital signs are normal. Laparoscopic surgical scars are well healed. Endoscopy shows benign mucosa to the proximal duodenum. A barium swallow study reveals an extremely narrowed duodenum. Which of the following structures is most likely responsible for this patient’s current symptoms?", "answer": "Superior mesenteric artery", "options": {"A": "Superior mesenteric artery", "B": "Pylorus of the stomach", "C": "Gastroduodenal artery", "D": "Gallbladder", "E": "Inferior mesenteric artery"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old man is seen in the emergency department for back pain that has been getting progressively worse over the last 4 days. Upon further questioning, he also notes that he has been having a tingling and burning sensation rising up from his feet to his knees bilaterally. The patient states he is having difficulty urinating and having bowel movements over the last several days. His temperature is 97.4°F (36.3°C), blood pressure is 122/80 mmHg, pulse is 85/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam is notable for weak leg flexion bilaterally along with decreased anal sphincter tone. Which of the following is the best next step in management?", "answer": "MRI", "options": {"A": "CT", "B": "Emergency surgery", "C": "Lumbar puncture", "D": "MRI", "E": "Pulmonary function tests"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old man presents with a long history of ulcers on the bottom of his feet. He recalls having a similar looking ulcer on the side of his penis when he was 19 years old for which he never sought treatment. The patient denies any fever, chills, or constitutional symptoms. He reports multiple sexual partners and a very promiscuous sexual history. He has also traveled extensively as a writer since he was 19. The patient is afebrile, and his vital signs are within normal limits. A rapid plasma reagin (RPR) test is positive, and the result of a Treponema pallidum particle agglutination (TP-PA) is pending. Which of the following findings would most likely be present in this patient?", "answer": "Positive Romberg's sign", "options": {"A": "Hyperreflexia", "B": "Wide-based gait with a low step", "C": "Positive Romberg's sign", "D": "Memory loss", "E": "Agraphesthesia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 44-year-old man presents for a checkup. The patient says he has to urinate quite frequently but denies any dysuria or pain on urination. Past medical history is significant for diabetes mellitus type 2 and hypertension, both managed medically, as well as a chronic mild cough for the past several years. Current medications are metformin, aspirin, rosuvastatin, captopril, and furosemide. His vital signs are an irregular pulse of 74/min, a respiratory rate of 14/min, a blood pressure of 130/80 mm Hg, and a temperature of 36.7°C (98.0°F). His BMI is 32 kg/m2. On physical examination, there are visible jugular pulsations present in the neck bilaterally. Laboratory findings are significant for the following:\nGlycated Hemoglobin (Hb A1c) 7.5%\n Fasting Blood Glucose 120 mg/dL\nSerum Electrolytes\nSodium 138 mEq/L\nPotassium 3.9 mEq/L\nChloride 101 mEq/L\nSerum Creatinine 1.3 mg/dL\nBlood Urea Nitrogen 18 mg/dL\nWhich of the following is the next best step in the management of this patient?", "answer": "Start exenatide.", "options": {"A": "Stop metformin.", "B": "Replace captopril with valsartan.", "C": "Start rosiglitazone.", "D": "Stop furosemide.", "E": "Start exenatide."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 39-year-old woman presents to the clinic with complaints of constipation for the past 2 weeks. She reports that it has been getting increasingly difficult to pass stool to the point that she would go for 2-3 days without going to the bathroom. Prior to this, she passed stool every day without difficulty. She denies weight changes, headaches, chest pain, or abdominal pain but endorses fatigue. Her past medical history is significant for 2 episodes of kidney stones within the past 3 months. A physical examination is unremarkable. Laboratory studies are done and the results are shown below:\n\nSerum:\nNa+: 138 mEq/L\nCl-: 97 mEq/L\nK+: 3.9 mEq/L\nHCO3-: 24 mEq/L \nBUN: 10 mg/dL\nGlucose: 103 mg/dL\nCreatinine: 1.1 mg/dL\nThyroid-stimulating hormone: 3.1 uU/mL\nCa2+: 12.1 mg/dL\nPhosphate: 1.2 mg/dL (Normal: 2.5-4.5 mg/dL)\n\nWhat is the most likely explanation for this patient’s low phosphate levels?", "answer": "Inhibition of sodium-phosphate cotransporter at the proximal convoluted tubule (PCT)", "options": {"A": "Chronic renal disease caused by recurrent renal stones", "B": "Defective G-coupled calcium-sensing receptors in multiple tissues", "C": "Hereditary malfunction of phosphate absorption at the small brush border", "D": "Increase in calcium-sodium cotransporter activity at the distal convoluted tubule (DCT)", "E": "Inhibition of sodium-phosphate cotransporter at the proximal convoluted tubule (PCT)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old man presents to the emergency department with a complaint of rectal bleeding. He describes blood mixed in with the stool, which is associated with a change in his normal bowel habit such that he is going more frequently than normal. He also has some crampy left-sided abdominal pain and weight loss. His symptoms started 2 months ago, but he thought they are due to lack of dietary fiber intake and excess consumption of red meat. He has had type 2 diabetes mellitus for 35 years for which he takes metformin. He also uses daily low-dose aspirin for cardioprotection and occasional naproxen for knee pain. His family history is irrelevant. On examination, his abdomen and digital rectal examination are normal. Colonoscopy shows an ulcerating mucosal lesion with a narrow bowel lumen and biopsy shows a moderately differentiated adenocarcinoma. Which of the following is the greatest risk factor for colorectal cancer in this patient?", "answer": "Increasing age", "options": {"A": "Lack of dietary fiber intake", "B": "Increasing age", "C": "Low-dose aspirin use", "D": "Metformin use", "E": "Naproxen use"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-year-old male presents to the emergency department for fatigue and lethargy. Upon presentation, the patient is found to be severely dehydrated. The patient's mother says that he has been having non-bloody diarrhea for a day. She also says that the patient has not received any vaccinations after 6 months and currently attends a daycare center. The responsible microbe is isolated and its structure is analyzed. Which of the following organisms is most likely responsible for the symptoms seen in this child.", "answer": "Rotavirus", "options": {"A": "Campylobacter jejuni", "B": "Salmonella", "C": "Shigella", "D": "Rotavirus", "E": "Norovirus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old boy is brought to the physician by his mother for the evaluation of delay in attaining developmental milestones. He could sit upright by 14 months and has not been able to walk without support. He can build a tower of 3 blocks and cannot use utensils to feed himself. He speaks in unclear 2-word phrases and cannot draw a circle yet. His mother has noticed him hitting his head against the wall on multiple occasions. He is at 20th percentile for height and at 50th percentile for weight. Vitals signs are within normal limits. Examination shows multiple lacerations of his lips and tongue. There are multiple healing wounds over his fingers. Neurological examination shows increased muscle tone in all extremities. Laboratory studies show:\nHemoglobin 10.1 g/dL\nMean corpuscular volume 103 μm3\nSerum\nNa+ 142 mEq/L\nCl- 101 mEq/:\nK+ 4.1 mEq/L\nCreatinine 1.6 mg/dL\nUric acid 12.3 mg/dL\nWhich of the following is the most likely cause of this patient's findings?\"", "answer": "Hypoxanthine-guanine phosphoribosyltransferase deficiency", "options": {"A": "FMR1 gene mutation", "B": "MECP2 gene mutation", "C": "Branched-chain alpha-ketoacid dehydrogenase complex deficiency", "D": "Hypoxanthine-guanine phosphoribosyltransferase deficiency", "E": "Microdeletion of paternal chromosome 15"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old man presents with the complaint of loose and watery stools for the past 3 days. He is now having bowel movements four to five times a day. He denies any blood or mucus in the stool. He also complains of abdominal pain and fatigue. Furthermore, he feels nauseous and does not feel like drinking anything. His urine is visibly yellow and low in volume. He recently returned from a trip to South America where he enjoyed all the local delicacies. He is most concerned about his urine color and volume. Which segment of the nephron is primarily responsible for these changes?", "answer": "Loop of Henle", "options": {"A": "Glomerulus", "B": "Proximal convoluted tubule", "C": "Proximal straight tubule", "D": "Loop of Henle", "E": "Distal tubule"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old male presents to the ER with generalized tonic-clonic seizures. He does not have a prior history of seizures and has not taken any drugs except for his daily asthma medication. Which of the following is associated with seizures:", "answer": "Theophylline", "options": {"A": "Albuterol", "B": "Ipratropium", "C": "Cromolyn", "D": "Theophylline", "E": "Prednisone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Please refer to the summary above to answer this question\nThis patient is at greatest risk of damage to which of the following cardiovascular structures?\"\n\"Patient Information\nAge: 44 years\nGender: M, self-identified\nEthnicity: Caucasian\nSite of Care: office\nHistory\nReason for Visit/Chief Concern: “I am thirsty all the time, and it's getting worse.”\nHistory of Present Illness:\n6-month history of increased thirst\nhas had to urinate more frequently for 4 months; urinates every 3–4 hours\nfeels generally weaker and more tired than usual\nhas also had a 1-year history of joint pain in the hands\nPast Medical History:\ngastroesophageal reflux disease\ntension headaches\nSocial History:\nhas smoked one-half pack of cigarettes daily for 15 years\noccasionally drinks two or three beers on weekends\nused to be sexually active with his husband but has been losing interest in sexual activity for the past 6 months\nMedications:\npantoprazole, amitriptyline, multivitamin\nAllergies:\nno known drug allergies\nPhysical Examination\nTemp Pulse Resp BP O2 Sat Ht Wt BMI\n37.2°C\n(99.0°F)\n78/min 16/min 127/77 mm Hg –\n188 cm\n(6 ft 2 in)\n85 kg\n(187 lb)\n24 kg/m2\nAppearance: no acute distress\nHEENT: sclerae anicteric; no oropharyngeal erythema or exudate\nPulmonary: clear to auscultation\nCardiac: regular rate and rhythm; normal S1 and S2; no murmurs, rubs, or gallops\nAbdominal: no tenderness, guarding, masses, or bruits; the liver span is 15 cm\nPelvic: small, firm testes; no nodules or masses\nExtremities: tenderness to palpation and stiffness of the metacarpophalangeal joints of both hands\nSkin: diffusely hyperpigmented\nNeurologic: alert and oriented; cranial nerves grossly intact; no focal neurologic deficits\"", "answer": "Cardiac conduction system", "options": {"A": "Pulmonary valve", "B": "Cardiac septum", "C": "Coronary artery", "D": "Cardiac conduction system", "E": "Temporal artery\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old woman presents with altered taste and a gritty sensation in her eyes for the last month. She mentions that she needs to drink water frequently and often feels that her mouth and throat are dry. On physical examination, she has bilateral enlargement of the parotid glands and dry conjunctivae. Her physical examination and laboratory findings suggest a diagnosis of sicca syndrome. In addition to non-pharmacological measures, a drug is prescribed to improve symptoms related to dryness of mouth by increasing salivation. Which of the following is the mechanism of action of the drug that most likely is being prescribed to this patient?", "answer": "Selective M3 muscarinic receptor agonist", "options": {"A": "Selective M3 muscarinic receptor antagonist", "B": "Selective M1 muscarinic receptor antagonist", "C": "Selective M2 muscarinic receptor agonist", "D": "Selective M2 muscarinic receptor antagonist", "E": "Selective M3 muscarinic receptor agonist"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 54-year-old man with alcoholism comes to the emergency department because of vomiting blood for 6 hours. He has had 3–4 episodes in which he has vomited dark red blood during this period. He has had no epigastric pain or tarry stools. On arrival, his temperature is 37.3°C (99.1°F), pulse is 134/min, and blood pressure is 80/50 mm Hg. He is resuscitated with 0.9% saline and undergoes an emergency upper endoscopy, which shows actively bleeding varices. Band ligation of the varices is done and hemostasis is achieved. He is diagnosed with Child class B cirrhosis. He is concerned about the possibility of recurrence of such an episode. He is asked to abstain from alcohol, to which he readily agrees. In addition to non-selective beta-blocker therapy, which of the following is the most appropriate recommendation to prevent future morbidity and mortality from this condition?", "answer": "Variceal ligation", "options": {"A": "Octreotide therapy", "B": "Terlipressin", "C": "Transjugular intrahepatic portosystemic shunt", "D": "Variceal sclerotherapy", "E": "Variceal ligation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 38-year-old man presents to his primary care practitioner for 2 months of rectal bleeding. He also reports occasional diarrhea and abdominal pain. His family history is relevant for his father and uncle, who died from complications of colorectal cancer. Colonoscopy shows more than 10 colorectal adenomas. Which of the following genes is most likely affected in this patient?", "answer": "APC", "options": {"A": "RAS", "B": "TP53", "C": "APC", "D": "hMLH1", "E": "PPAR"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 36-year-old male is taken to the emergency room after jumping from a building. Bilateral fractures to the femur were stabilized at the scene by emergency medical technicians. The patient is lucid upon questioning and his vitals are stable. Pain only at his hips was elicited. Cervical exam was not performed. What is the best imaging study for this patient?", "answer": "Anterior-posterior (AP) and lateral radiographs of hips, knees, lumbar, and cervical area", "options": {"A": "Lateral radiograph (x-ray) of hips", "B": "Computed tomagraphy (CT) scan of his hips and lumbar area", "C": "Anterior-posterior (AP) and lateral radiographs of hips, knees, lumbar, and cervical area", "D": "Magnetic resonance imaging (MRI) of hips, knees, lumbar, and cervical area", "E": "AP and lateral radiographs of hips"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the dermatology clinic to have a basal cell carcinoma excised from his upper back. The lesion measures 2.3 x 3.2 cm. He has a medical history significant for hypertension and diabetes mellitus type II, for which he takes lisinopril and metformin, respectively. He has had a basal cell carcinoma before which was excised in the clinic without complications. Which of the following modes of anesthesia should be used for this procedure?", "answer": "Local anesthesia", "options": {"A": "Local anesthesia", "B": "Peripheral nerve block", "C": "Spinal anesthesia", "D": "Moderate sedation", "E": "General anesthesia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 53-year-old man is brought to the physician by his wife because of strange behavior and emotional outbursts for the past 6 months. He was previously healthy and physically active, but he recently started binge-eating candy and stopped exercising. He was fired from his job for inappropriate behavior after he undressed in the office and made lewd remarks to several female coworkers. He claims there is nothing wrong with his behavior. On mental status examination, he is alert and irritable but cooperative. Short-term recall is normal but he has some word-finding difficulties. Babinski reflex is positive bilaterally. This patient's symptoms are most likely due to a degenerative process in which of the following regions of the brain?", "answer": "Frontal cortex", "options": {"A": "Frontal cortex", "B": "Substantia nigra", "C": "Caudate nucleus", "D": "Hippocampus", "E": "Corona radiata"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 10-month-old infant is brought in by his parents because he is vomiting and not passing stool. His parents say he has vomited multiple times over the past couple of hours, but the most recent vomit was green. The patient has no significant past medical history. On physical examination, the patient is irritable and crying. On palpation in the periumbilical region, an abdominal mass is present. Emergency laparotomy is performed, which shows a part of the patient’s intestine folded into the section adjacent to it. Which of the following is the most likely diagnosis for this patient?", "answer": "Intussusception", "options": {"A": "Hirschsprung’s disease", "B": "Meckel’s diverticulum", "C": "Duodenal atresia", "D": "Pyloric stenosis", "E": "Intussusception"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old woman comes to the physician because of increased urinary frequency and pain on urination for two days. She has had three similar episodes over the past year that resolved with antibiotic treatment. She has no history of serious illness. She is sexually active with one male partner; they do not use barrier contraception. Upon questioning, she reports that she always urinates and cleans herself after sexual intercourse. She drinks 2–3 liters of fluid daily. Her only medication is a combined oral contraceptive. Her temperature is 36.9°C (98.4°F), pulse is 65/min, and blood pressure is 122/65 mm Hg. Examination shows mild tenderness to palpation in the lower abdomen. The remainder of the examination shows no abnormalities. Urinalysis shows WBCs and rare gram-positive cocci. Which of the following is the most appropriate recommendation to prevent similar episodes in the future?", "answer": "Daily oral trimethoprim-sulfamethoxazole\n\"", "options": {"A": "Daily intake of cranberry juice", "B": "Postcoital vaginal probiotics", "C": "Treatment of the partner with intramuscular ceftriaxone", "D": "Postcoital oral amoxicillin-clavulanate", "E": "Daily oral trimethoprim-sulfamethoxazole\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A patient presents to the emergency department with arm pain. The patient recently experienced an open fracture of his radius when he fell from a ladder while cleaning his house. Surgical reduction took place and the patient's forearm was put in a cast. Since then, the patient has experienced worsening pain in his arm. The patient has a past medical history of hypertension and asthma. His current medications include albuterol, fluticasone, loratadine, and lisinopril. His temperature is 99.5°F (37.5°C), blood pressure is 150/95 mmHg, pulse is 90/min, respirations are 19/min, and oxygen saturation is 99% on room air. The patient's cast is removed. On physical exam, the patient's left arm is tender to palpation. Passive motion of the patient's wrist and fingers elicits severe pain. The patient's left radial and ulnar pulse are both palpable and regular. The forearm is soft and does not demonstrate any bruising but is tender to palpation. Which of the following is the next best step in management?", "answer": "Emergency fasciotomy", "options": {"A": "Ibuprofen and reassurance", "B": "Replace the cast with a sling", "C": "Radiography", "D": "Measurement of compartment pressure", "E": "Emergency fasciotomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-month-old boy is brought to the pediatrician for a wellness visit. Upon examination, the physician notes severe burns on the sun-exposed areas of the skin, including the face (especially the ears and nose), dorsal aspect of the hands, shoulders, and dorsal aspect of his feet. The child has very fair skin and blond hair. The parents insist that the child has not spent any extraordinary amount of time in the sun, but they admit that they rarely apply sunscreen. Which of the following physical factors is the most likely etiology for the burns?", "answer": "UV-B radiation", "options": {"A": "Infrared radiation", "B": "Child abuse", "C": "UV-B radiation", "D": "Ionizing radiation", "E": "Gamma radiation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Three days after undergoing an open cholecystectomy, a 73-year-old man has fever and abdominal pain. He has hypertension, type 2 diabetes mellitus, chronic obstructive pulmonary disease, and benign prostatic hyperplasia. He had smoked one pack of cigarettes daily for 40 years but quit 1 year ago. He does not drink alcohol. Prior to admission to the hospital, his medications included lisinopril, metformin, ipratropium, and tamsulosin. He appears acutely ill and lethargic. His temperature is 39.5°C (103.1°F), pulse is 108/min, respirations are 18/min, and blood pressure is 110/84 mm Hg. He is oriented only to person. Examination shows a 10-cm subcostal incision that appears dry and non-erythematous. Scattered expiratory wheezing is heard throughout both lung fields. His abdomen is distended with tenderness to palpation over the lower quadrants. Laboratory studies show:\nHemoglobin 10.1 g/dl\nLeukocyte count 19,000/mm3\nSerum\nGlucose 180 mg/dl\nUrea Nitrogen 25 mg/dl\nCreatinine 1.2 g/dl\nLactic acid 2.5 mEq/L (N = 0.5 - 2.2 mEq/L)\nUrine\nProtein 1+\nRBC 1–2/hpf\nWBC 32–38/hpf\nWhich of the following is the most likely underlying mechanism of this patient's current condition?\"", "answer": "Bladder outlet obstruction", "options": {"A": "Wound contamination", "B": "Impaired alveolar ventilation", "C": "Peritoneal inflammation", "D": "Bladder outlet obstruction", "E": "Intraabdominal abscess formation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old man presents to his primary care physician complaining of increasingly frequent headaches. He also reports that his hats and wedding ring do not fit anymore. His temperature is 99°F (37.2°C), blood pressure is 145/80 mmHg, pulse is 85/min, and respirations are 16/min. Physical examination is notable for frontal bossing, a prominent jaw, and an enlarged tongue. A chest radiograph reveals mild cardiomegaly. Serum insulin-like growth factor 1 levels are significantly elevated. Which of the following conditions is this patient at greatest risk for?", "answer": "Carpal tunnel syndrome", "options": {"A": "Pheochromocytoma", "B": "Medullary thyroid carcinoma", "C": "Osteoid osteoma", "D": "Carpal tunnel syndrome", "E": "Osteosarcoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 78-year-old man presents to the clinic complaining of shortness of breath at rest and with exertion. He also complains of difficulty breathing while lying down. He also is concerned because he startles from sleep and feels like he is choking. These symptoms have been bothering him for the last several weeks and they are getting worse. He has been afebrile with no known sick contacts. 6 months ago, he had an acute myocardial infarction from which he recovered and until recently had felt well. He has a history of hyperlipidemia for which he takes atorvastatin. His temperature is 37.0°C (98.6°F), the pulse is 85/min, the respiratory rate is 14/min, and the blood pressure is 110/75 mm Hg. On physical examination, his heart has a regular rate and rhythm. He has bilateral crackles in both lungs. An echocardiogram is performed and shows a left ventricular ejection fraction of 33%. What medication should be started?", "answer": "Captopril", "options": {"A": "Niacin", "B": "Captopril", "C": "Verapamil", "D": "Levofloxacin", "E": "Nitroglycerin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man is brought in by his daughter who is concerned about his recent memory impairment. The patient’s daughter says she has noticed impairment in memory and functioning for the past month. She says that he has forgotten to pay bills and go shopping, and, as a result, the electricity was cut off due to non-payment. She also says that last week, he turned the stove on and forgot about it, resulting in a kitchen fire. The patient has lived by himself since his wife died last year. He fondly recalls living with his wife and how much he misses her. He admits that he feels ‘down’ most days of the week living on his own and doesn’t have much energy. When asked about the kitchen fire and problems with the electricity, he gets defensive and angry. At the patient’s last routine check-up 3 months ago, he was healthy with no medical problems. His vital signs are within normal limits. On physical examination, the patient appears to have a flat affect. Which of the following is the most likely diagnosis in this patient?", "answer": "Pseudodementia", "options": {"A": "Pseudodementia", "B": "Dementia", "C": "Delirium", "D": "Both dementia and delirium", "E": "Pick’s disease"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old woman comes to the physician because of a 3-day history of fever, fatigue, loss of appetite, cough, and chest pain. Physical examination shows diffuse inspiratory crackles over the left lung field. An x-ray of the chest shows hilar lymphadenopathy and well-defined nodules with central calcifications. Urine studies show the presence of a polysaccharide antigen. A biopsy specimen of the lung shows cells with basophilic, crescent-shaped nuclei and pericellular halos located within macrophages. This patient's history is most likely to show which of the following?", "answer": "Exposure to bat droppings", "options": {"A": "Treatment with inhaled glucocorticoids", "B": "Visit to Arizona desert", "C": "Recent trip to Brazil", "D": "Previous mycobacterial infection", "E": "Exposure to bat droppings"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Researchers are studying the relationship between heart disease and alcohol consumption. They review the electronic medical records of 500 patients at a local hospital during the study period and identify the presence or absence of acute coronary syndrome (ACS) and the number of alcoholic drinks consumed on the day of presentation. They find that there is a lower prevalence of acute coronary syndrome in patients who reported no alcohol consumption or 1 drink daily compared with those who reported 2 or more drinks. Which of the following is the most accurate description of this study type?", "answer": "Cross-sectional study", "options": {"A": "Randomized controlled trial", "B": "Case-control study", "C": "Cross-sectional study", "D": "Retrospective study", "E": "Prospective study"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old man presents to his primary care provider for abdominal pain. He reports that he has had a dull, burning pain for several months that has progressively gotten worse. He also notes a weight loss of about five pounds over that time frame. The patient endorses nausea and feels that the pain is worse after meals, but he denies any vomiting or diarrhea. He has a past medical history of hypertension, and he reports that he has been under an unusual amount of stress since losing his job as a construction worker. His home medications include enalapril and daily ibuprofen, which he takes for lower back pain he developed at his job. The patient drinks 1-2 beers with dinner and has a 25-pack-year smoking history. His family history is significant for colorectal cancer in his father and leukemia in his grandmother. On physical exam, the patient is moderately tender to palpation in the epigastrium. A fecal occult test is positive for blood in the stool.\n\nWhich of the following in the patient’s history is most likely causing this condition?", "answer": "Medication use", "options": {"A": "Physiologic stress", "B": "Alcohol use", "C": "Medication use", "D": "Smoking history", "E": "Family history of cancer"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old man being treated for major depressive disorder returns to his psychiatrist complaining that he has grown weary of the sexual side effects. Which other medication used to treat major depressive disorder may be appropriate as a stand-alone or add-on therapy?", "answer": "Buproprion", "options": {"A": "Paroxetine", "B": "Venlafaxine", "C": "Aripiprazole", "D": "Buproprion", "E": "Cyproheptadine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old man presents to the emergency department with a severe pulsatile headache for an hour. He says that he is having palpitations as well. He adds that he has had several episodes of headache in the past which resolved without seeking medical attention. He is a non-smoker and does not drink alcohol. He denies use of any illicit drugs. He looks scared and anxious. His temperature is 37°C (98.6°F), respirations are 25/min, pulse is 107/min, and blood pressure is 221/161 mm Hg. An urgent urinalysis reveals elevated plasma metanephrines. What is the next best step in the management of this patient?", "answer": "Phenoxybenzamine followed by propanolol", "options": {"A": "Propranolol followed by phenoxybenzamine", "B": "Phenoxybenzamine followed by propanolol", "C": "Amlodipine", "D": "Emergent surgery", "E": "Hydralazine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is comparing the risk of adverse effects among various antiarrhythmic medications. One of the drugs being studied primarily acts by blocking the outward flow of K+ during myocyte repolarization. Further investigation shows that the use of this drug is associated with a lower rate of ventricular tachycardia, ventricular fibrillation, and torsade de points when compared to similar drugs. Which of the following drugs is most likely being studied?", "answer": "Amiodarone", "options": {"A": "Esmolol", "B": "Sotalol", "C": "Procainamide", "D": "Verapamil", "E": "Amiodarone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 67-year-old man presents with fatigue, progressive abdominal distention and yellow skin coloration for the past 2 weeks. He denies fever, chills, or other symptoms. Past medical history is unremarkable. He reports heavy alcohol consumption for the past several years but says he quit recently. On physical examination, the patient appears jaundiced and is ill-appearing. There is shifting dullness presents on abdominal percussion with a positive fluid wave. Sclera are icteric. Bilateral gynecomastia is present. Laboratory findings are significant for the following:\nHgb 13 g/dL\nLeukocyte count 4,500/mm3\nPlatelets 86,000/mm3\nAspartate transaminase (AST) 108 U/L\nAlanine transaminase (ALT) 55 U/L\nGGT 185 U/L\nUrea 23 mg/dL\nIron 120 μg/dL\nFerritin 180 μg/dL\nTransferrin saturation 40%\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Alcoholic liver disease", "options": {"A": "Hemochromatosis", "B": "Chronic viral hepatitis", "C": "Alcoholic liver disease", "D": "Hepatic adenoma", "E": "Non alcoholic fatty liver disease"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A recent study attempted to analyze whether increased \"patient satisfaction\" driven healthcare resulted in increased hospitalization. Using this patient population, the sociodemographics, health status, and hospital use were assessed. Next year, patient satisfaction with health care providers was assessed using 5 items from the Consumer Assessment of Health Plans Survey. Which of the following best describes this study design?", "answer": "Prospective cohort", "options": {"A": "Cross-sectional study", "B": "Prospective case-control", "C": "Prospective cohort", "D": "Retrospective case-control", "E": "Retrospective cohort"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 16-year-old man presents to the emergency department complaining of episodes of pounding headache, chest fluttering, and excessive sweating. He has a past history of kidney stones that are composed of calcium oxalate. He does not smoke or drink alcohol. Family history reveals that his mother died of thyroid cancer. Vital signs reveal a temperature of 37.1°C (98.7°F), blood pressure of 200/110 mm Hg and pulse of 120/min. His 24-hour urine calcium, serum metanephrines, and serum normetanephrines levels are all elevated. Mutation of which of the following genes is responsible for this patient's condition?", "answer": "RET proto-oncogene", "options": {"A": "BRAF", "B": "RET proto-oncogene", "C": "BCR-ABL", "D": "BCL2", "E": "HER-2/neu (C-erbB2)"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old man presents to his primary care physician for fatigue. The patient states that he has not been sleeping well and requests sleep medication to help him with his fatigue. He recently changed his diet to try to increase his energy and has been on a vegetarian diet for the past several months. The patient has no significant past medical history. He smokes 1 pack of cigarettes per day and drinks 5 alcoholic beverages per day. The patient has lost 12 pounds since his last visit 1 month ago. Physical exam demonstrates a tired man. He appears thin, and his skin and sclera are icteric. Abdominal ultrasound is notable for a thin-walled and enlarged gallbladder. A urine sample is collected and is noted to be amber in color. Which of the following is the most likely diagnosis?", "answer": "Pancreatic adenocarcinoma", "options": {"A": "Autoimmune hemolytic anemia", "B": "Cholangiocarcinoma", "C": "Gallbladder adenocarcinoma", "D": "Iron deficiency anemia", "E": "Pancreatic adenocarcinoma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old man comes to the emergency department because of a 3-hour history of pain and redness of both eyes. He has new blurry vision and difficulty opening his eyes in bright surroundings. He has not had any recent trauma. He uses contact lenses daily. He had surgery on his left eye 6 months ago after a penetrative trauma caused by a splinter. His vital signs are within normal limits. Physical examination shows congestion of the perilimbal conjunctivae bilaterally. Visual acuity is decreased bilaterally. Ocular movements are normal. Slit-lamp examination shows a cornea with normal contours and leukocytes in the anterior chambers of both eyes. The eyelids, eyelashes, and lacrimal ducts show no abnormalities. Which of the following is the most likely cause of this patient's condition?", "answer": "Autoimmune reaction against retinal antigens", "options": {"A": "Reactivation of herpes zoster virus", "B": "Autoimmune reaction against retinal antigens", "C": "Corneal infection with Pseudomonas aeruginosa", "D": "Impaired drainage of aqueous humor", "E": "Age-related denaturation of lens proteins"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 29-year-old woman presents with shortness of breath and chest pain for the past week. She says her chest pain is aggravated by deep breathing and she becomes short of breath while walking upstairs in her home. She also has been feeling feverish and fatigued for the past week, as well as pain in her wrists, hands, and left knee. Review of systems is significant for a 4.5 kg (10.0 lb) weight loss over the previous month Past medical history consists of 2 spontaneous abortions, both of which occurred in the 1st trimester. On physical examination, there is a pink rash present on over her face, which is aggravated by exposure to sunlight. There are decreased breath sounds on the right. A chest radiograph is performed which reveals evidence of a right pleural effusion. Serum ANA and anti-dsDNA autoantibodies are positive. Urinalysis is unremarkable. Errors with which of the following is most likely to lead to her disease?", "answer": "Fas-FasL interaction", "options": {"A": "Cytotoxic CD8+ T cells", "B": "Intrinsic pathway", "C": "Necrosis", "D": "Fas-FasL interaction", "E": "Bcl-2 overexpression"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is studying severely ill patients who experience hypoglycemia and ketonuria during times of fasting. The investigator determines that during these episodes, amino acids liberated from muscle proteins are metabolized to serve as substrates for gluconeogenesis. Nitrogen from this process is transported to the liver primarily in the form of which of the following molecules?", "answer": "Alanine", "options": {"A": "Pyruvate", "B": "Arginine", "C": "Alanine", "D": "α-ketoglutarate", "E": "Glutamate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old man presents to the emergency room with an acute myocardial infarction. Twenty-four hours after admission to the cardiac intensive care unit, he develops oliguria. Laboratory tests show that his serum BUN is 59 mg/dL and his serum creatinine is 6.2 mg/dL. Renal biopsy reveals necrosis of the proximal tubules and thick ascending limb of Henle's loop. Which of the following would you most likely observe on a microscopic examination of this patient's urine?", "answer": "Muddy brown casts", "options": {"A": "White blood cell casts", "B": "Fatty casts", "C": "Muddy brown casts", "D": "Hyaline casts", "E": "Broad waxy casts"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 26-year-old man comes to the physician because of episodic palpitations for the past 2 months. He has the feeling that sometimes his heart “skips a beat”. His father has a history of atrial fibrillation and myocardial infarction. He has smoked one pack of cigarettes daily for 5 years. He drinks 1–2 beers on the weekends. His vital signs are within normal limits. Physical examination reveals a regular pulse. Cardiopulmonary examination shows no abnormalities. Serum studies, including electrolytes and creatinine, are within normal limits. An excerpt of 24h Holter monitoring is shown. Echocardiography is normal. Which of the following is the most appropriate next step in management?", "answer": "Smoking cessation", "options": {"A": "Diltiazem therapy", "B": "Coronary angiography", "C": "Metoprolol therapy", "D": "Permanent pacemaker placement", "E": "Smoking cessation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 60-year-old woman is rushed to the emergency room after falling on her right elbow while walking down the stairs. She cannot raise her right arm. Her vital signs are stable, and the physical examination reveals loss of sensation over the upper lateral aspect of the right arm and shoulder. A radiologic evaluation shows a fracture of the surgical neck of the right humerus. Which of the following muscles is supplied by the nerve that is most likely damaged?", "answer": "Teres minor", "options": {"A": "Infraspinatus", "B": "Teres minor", "C": "Supraspinatus", "D": "Teres major", "E": "Subscapularis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man presents to his gastroenterologist for trouble swallowing. The patient states that whenever he eats solids, he regurgitates them back up. Given this patient's suspected diagnosis, the gastroenterologist performs a diagnostic test. Several hours later, the patient presents to the emergency department with chest pain and shortness of breath. His temperature is 99.5°F (37.5°C), blood pressure is 130/85 mmHg, pulse is 60/min, respirations are 12/min, and oxygen saturation is 99% on room air. On physical exam, the patient demonstrates a normal cardiopulmonary exam. His physical exam demonstrates no tenderness of the neck, a normal oropharynx, palpable crepitus above the clavicles, and minor lymphadenopathy. Which of the following is the best next step in management?", "answer": "Gastrografin swallow", "options": {"A": "Barium swallow", "B": "Urgent surgery", "C": "Magnetic resonance imaging", "D": "Gastrografin swallow", "E": "Ultrasound"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A four-year-old boy is brought to his pediatrician by his mother for recurrent nosebleeds. The mother reports that the boy has had five nosebleeds within the past 2 weeks, each lasting between 15 and 20 minutes. The patient was born at term and has been hospitalized twice for pneumonia treatment. There is no family history of serious illness. The patient is at the 8th percentile for height and the 30th percentile for weight. Vital signs are within normal limits. Examination shows a small, thin child with two flat, dark brown areas of hyperpigmentation across the upper back and a similar discoloration on the left buttock. There is bilateral esotropia. Laboratory studies show a hemoglobin concentration of 9.3 g/dL, mean corpuscular volume of 107 μm3, leukocyte count of 3,800/mm3, and platelet count of 46,000/mm3. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Defect in DNA crosslink repair", "options": {"A": "Defect in DNA crosslink repair", "B": "Mutation in WAS protein", "C": "Parvovirus B19 infection", "D": "Recent history of NSAID use", "E": "Postviral autoimmune reaction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old man presents to the physician with numbness and weakness in both legs for about a day. He also mentions that both thighs ache. His past medical history is not significant except for some diarrhea about 3 weeks ago. On physical examination, his temperature is 37.2ºC (99.0ºF), pulse rate is 108/min and respiratory rate is 14/min. His blood pressure is 122/82 mm Hg and 100/78 mm Hg in supine and upright positions, respectively. His neurologic evaluation reveals the presence of bilateral symmetrical weakness of the lower limbs, the absence of deep tendon reflexes, and negative Babinski sign. His sensorium and higher brain functions are normal. Which of the following options best explains the pathophysiological mechanism underlying the patient’s clinical features?", "answer": "Decreased neuronal excitability", "options": {"A": "Genetic overexpression of K+ channels in skeletal muscle", "B": "Decreased neuronal excitability", "C": "Decreased threshold for the generation and propagation of the action potential", "D": "Toxin-mediated blockade of voltage-gated fast Na+ channels", "E": "Autoantibody-mediated destruction of Ca2+ channels in the nerve endings at the neuromuscular junction"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Confident of your performance on Step 1 given your extensive utilization of Medbullets, you preemptively start to ponder your future specialty choice. You come across an analysis of lifestyle factors and how they affect medical student specialty choices. Image A depicts two scatter plots comparing the relationship between median income and weekly work hours on the difficulty of matching into specific specialties. Both associations are statistically significant. Which statement best describes the results?", "answer": "Median income has a stronger correlation with matching difficulty than weekly work hours", "options": {"A": "The harder the specialty is to match into, the higher the weekly work hours", "B": "The easier the specialty is to match into, the higher the median income", "C": "Weekly work hours has a stronger correlation with matching difficulty than median income", "D": "Median income has a stronger correlation with matching difficulty than weekly work hours", "E": "The higher the median income of a specialty the shorter the weekly work hours"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old man undergoes parathyroidectomy for treatment-resistant hyperparathyroidism. The procedure is complicated by brisk bleeding from an artery that travels along the external branch of the superior laryngeal nerve. To stop the bleeding, the artery is ligated at its origin. Which of the following is most likely the origin of the artery that was injured in this patient?", "answer": "External carotid artery", "options": {"A": "Subclavian artery", "B": "Internal carotid artery", "C": "External carotid artery", "D": "Thyrocervical trunk", "E": "Ascending pharyngeal artery\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year-old man presents to the emergency department with a progressively worsening cough, wheezes, and chest tightness over the last 2 days. He has a history of moderate persistent asthma and his maintenance regimen consists of an inhaled corticosteroid, a long-acting beta-agonist, and albuterol as rescue therapy. He has not improved with his rescue inhaler despite increased use. He reports prior exposure to a person who had symptoms of a respiratory infection. His temperature is 37.4°C (99.3°F), blood pressure is 101/68 mm Hg, heart rate is 99/min, and respiratory rate is 32/min. Physical examination reveals widespread polyphonic wheezes but equal air entry. His oxygen saturation is 92% on room air. The presence of which of the following categorizes this patient’s condition as life-threatening?", "answer": "Respiratory acidosis", "options": {"A": "Peak expiratory flow rate (PEFR) >70%", "B": "Dyspnea that limits usual daily activity", "C": "Symptoms lasting for > 3 days after starting treatment", "D": "Respiratory alkalosis", "E": "Respiratory acidosis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old woman is brought to the physician by her father because of a change in her behavior over the past 8 months. The father says that his daughter has become increasingly withdrawn; she has not answered any phone calls or visited her family and friends. The patient says that she has to stay at home because a foreign intelligence service is monitoring her. She thinks that they are using a magnetic field to read her mind. Mental status exam shows disjointed and perseverative thinking. She is anxious and has a flat affect. Which of the following is the most likely diagnosis?", "answer": "Schizophrenia", "options": {"A": "Schizophrenia", "B": "Delusional disorder", "C": "Paranoid personality disorder", "D": "Schizoid personality disorder", "E": "Schizophreniform disorder"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-year-old boy is brought to his pediatrician's office by his parents for a scheduled visit. His father tells the physician that he has observed, on several occasions, that his son has difficulty breathing. This is more prominent when he is outside playing with his friends. These symptoms are increased during the spring and winter seasons, and, of late, the boy has one such episode almost every week. During these episodes, he usually wheezes, coughs, and seems to be winded as if something was restricting his ability to breathe. These symptoms have not affected his sleep at night. This breathlessness does not limit his daily activities, and whenever he does have an episode it subsides after he gets some rest. He does not have any other pertinent medical history and is not on any medication. His physical examination does not reveal any significant findings. The pediatrician checks his expiratory flow rate in the office and estimates it to be around 85% after conducting it three times. Which of the following drugs is the pediatrician most likely to start this patient on?", "answer": "Inhaled albuterol", "options": {"A": "Inhaled salmeterol", "B": "Inhaled albuterol", "C": "High-dose budesonide", "D": "Low-dose fluticasone", "E": "Oral prednisone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 18-year-old man presents with bloody diarrhea and weight loss. He undergoes endoscopic biopsy which shows pseudopolyps. Biopsies taken during the endoscopy show inflammation only involving the mucosa and submucosa. He is diagnosed with an inflammatory bowel disease. Which of the following was most likely found?", "answer": "Rectal involvement", "options": {"A": "Skip lesions", "B": "Noncaseating granuloma", "C": "Fistulas and strictures", "D": "Rectal involvement", "E": "Cobblestone mucosa"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old man presents to his primary care provider complaining of bilateral arm numbness. He was involved in a motor vehicle accident 3 months ago. His past medical history is notable for obesity and psoriatic arthritis. He takes adalimumab. His temperature is 99.3°F (37.4°C), blood pressure is 130/85 mmHg, pulse is 90/min, and respirations are 18/min. On exam, superficial skin ulcerations are found on his fingers bilaterally. His strength is 5/5 bilaterally in shoulder abduction, arm flexion, arm extension, wrist extension, finger abduction, and thumb flexion. He demonstrates loss of light touch and pinprick response in the distal tips of his 2nd and 5th fingertips and over the first dorsal web space. Vibratory sense is intact in the bilateral upper and lower extremities. Which of the following nervous system structures is most likely affected in this patient?", "answer": "Ventral white commissure", "options": {"A": "Ventral white commissure", "B": "Ventral horns", "C": "Cuneate fasciculus", "D": "Anterior corticospinal tract", "E": "Spinocerebellar tract"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 46-year-old Caucasian male with past medical history of HIV (CD4: 77/mm^3), hypertension, hyperlipidemia, and osteoarthritis presents to the emergency department with sudden weakness of his right hand. He reports that the weakness has gradually been getting worse and that this morning he dropped his cup of coffee. He has never had anything like this happen to him before, although he was hospitalized last year for pneumonia. He reports inconsistent adherence to his home medications, which include raltegravir, tenofovir, emtricitabine, TMP-SMX, hydrochlorothiazide, pravastatin, and occasional ibuprofen. His father died of a myocardial infarction at the age of 60, and his mother suffered a stroke at the age of 72. The patient's temperature is 102.6°F (39.2°C), blood pressure is 156/92 mmHg, pulse is 88/min, and respirations are 18/min. On neurological exam, he has 3/5 strength in the distal muscles of the right extremity with preserved sensation. His neurological exam is normal in all other extremities.\n\nWhich of the following is the best next step in management?", "answer": "Head CT", "options": {"A": "Lumbar puncture", "B": "Serology for Toxoplasma-specific IgG antibodies", "C": "Head CT", "D": "Empiric treatment with pyrimethamine-sulfadiazine", "E": "Empiric treatment with itraconazole"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl comes to the physician because of a 12-hour history of profuse watery diarrhea with flecks of mucus that started shortly after she returned from a trip to South America. She has not had any fever or nausea. Pulse is 104/min and blood pressure is 110/65 mm Hg. Physical examination shows dry mucous membranes and decreased skin turgor. Stool culture shows gram-negative, comma-shaped, flagellated bacilli. Therapy with oral rehydration solution is initiated. Which of the following is the most likely mechanism of this patient's diarrhea?", "answer": "Luminal chloride hypersecretion due to overactivation of adenylate cyclase", "options": {"A": "Reduced ability of water absorption in the colon due to rapid intestinal transit", "B": "Fluid and electrolyte loss due to inflammation of luminal surface epithelium", "C": "Luminal chloride hypersecretion due to overactivation of adenylate cyclase", "D": "Impaired intestinal motility due to degeneration of autonomic nerves", "E": "Excessive water excretion due to osmotically active solutes in the lumen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 16-year-old girl comes to her primary care physician for an annual check-up. She has no specific complaints. Her medical history is significant for asthma. She uses an albuterol inhaler as needed. She has no notable surgical history. Her mom had breast cancer and her grandfather died of colon cancer. She received all her childhood scheduled vaccinations up to age 8. She reports that she is doing well in school but hates math. She is sexually active with her boyfriend. They use condoms consistently, and they both tested negative recently for gonorrhea, chlamydia, syphilis and human immunodeficiency virus. She asks about birth control. In addition to educating the patient on her options for contraception, which of the following is the best next step in management?", "answer": "No HPV-related screening and administer HPV vaccine", "options": {"A": "Cytology and human papilloma virus (HPV) testing now and then every 3 years", "B": "Cytology and HPV testing now and then every 5 years", "C": "Cytology now and then every 3 years", "D": "No HPV-related screening as the patient is low risk", "E": "No HPV-related screening and administer HPV vaccine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-year-old boy with beta thalassemia requires regular blood transfusions a few times per month because of persistent anemia. He is scheduled for a splenectomy in the next several months. Samples obtained from the boy’s red blood cells show a malformed protein with a length of 160 amino acids (in normal, healthy red blood cells, the functional protein has a length of 146 amino acids). Which of the following best accounts for these findings?", "answer": "Splice site mutation", "options": {"A": "Frameshift mutation", "B": "Missense mutation", "C": "Nonsense mutation", "D": "Silent mutation", "E": "Splice site mutation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old woman comes to the physician because she has been unable to conceive for 2 years. The patient also reports monthly episodes of pelvic and back pain accompanied by painful diarrhea for 6 years. She takes naproxen for the pain, which has provided some relief. Menses have occurred at regular 28-day intervals since menarche at the age of 11 years and last for 7 days. She is sexually active with her husband and does not use contraception. Pelvic and rectal examination shows no abnormalities. A hysterosalpingogram is unremarkable. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Endometrial tissue outside the uterine cavity", "options": {"A": "Endometrial tissue outside the uterine cavity", "B": "Smooth muscle tumor arising from the myometrium", "C": "Primary failure of the ovaries", "D": "Scarring of the fallopian tubes", "E": "Increased secretion of androgens and luteinizing hormone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 41-year-old man presents to his primary care provider because of chest pain with activity for the past 6 months. Past medical history is significant for appendectomy at age 12 and, hypertension, and diabetes mellitus type 2 that is poorly controlled. He takes metformin and lisinopril but admits that he is bad at remembering to take them everyday. His father had a heart attack at 41 and 2 stents were placed in his heart. His mother is healthy. He drinks alcohol occasionally and smokes a half of a pack of cigarettes a day. He is a sales executive and describes his work as stressful. Today, the blood pressure is 142/85 and the body mass index (BMI) is 28.5 kg/m2. A coronary angiogram shows > 75% narrowing of the left anterior descending coronary artery. Which of the following is most significant in this patient?", "answer": "Diabetes mellitus", "options": {"A": "Diabetes mellitus", "B": "Hypertension", "C": "Family history", "D": "Obesity", "E": "Smoking"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old man is brought to the emergency department 30 minutes after falling from a height of 3 feet onto a sharp metal fence pole. He is unconscious. Physical examination shows a wound on the upper margin of the right clavicle in the parasternal line that is 3-cm-deep. Which of the following is the most likely result of this patient's injury?", "answer": "Pneumothorax due to pleural injury", "options": {"A": "Rotator cuff tear due to supraspinatus muscle injury", "B": "Pneumothorax due to pleural injury", "C": "Trapezius muscle paresis due to spinal accessory nerve injury", "D": "Hemathorax due to azygos vein injury", "E": "Traumatic aneurysm due to internal carotid artery injury"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-hour-old newborn is urgently transferred to the neonatal intensive care unit because he is found to be cyanotic and appears blue in all four extremities. He was born to a 42-year-old G1P1 mother who underwent no prenatal screening because she did not show up to her prenatal care visits. She has poorly controlled diabetes and hypertension. On physical exam, the infant is found to have slanted eyes, a flattened head, a large tongue, and a single palmar crease bilaterally. Furthermore, a single, loud S2 murmur is appreciated in this patient. Radiography shows a large oblong-shaped heart shadow. Based on this presentation, the neonatologist starts a medication that will temporarily ensure this patient's survival pending definitive fixation of the defect. The substance that was most likely administered in this case also has which of the following effects?", "answer": "Vascular vasodilation", "options": {"A": "Decreased platelet aggregation", "B": "Increased bronchial tone", "C": "Increased uterine tone", "D": "Vascular vasoconstriction", "E": "Vascular vasodilation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A syndrome caused by chromosomal anomalies is being researched in the immunology laboratory. Several congenital conditions are observed among the participating patients, mostly involving the thymus and the heart. Common facial features of affected individuals are shown in the image below. Flow cytometry analysis of patient samples reveals a CD19+ and CD3- result. What kind of congenital anomaly is generally observed in these patients, specifically in the thymus?", "answer": "Aplasia", "options": {"A": "Deformation", "B": "Agenesis", "C": "Aplasia", "D": "Malformation", "E": "Disruption"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the emergency department with confusion and a change in his behavior. The patient was in his usual state of health 3 days ago. He became more confused and agitated this morning thus prompting his presentation. The patient has a past medical history of depression, hypertension, diabetes, and Parkinson disease and is currently taking fluoxetine, lisinopril, insulin, metformin, and selegiline (recently added to his medication regimen for worsening Parkinson symptoms). He also takes oxycodone and clonazepam for pain and anxiety; however, he ran out of these medications last night. His temperature is 101°F (38.3°C), blood pressure is 111/78 mmHg, pulse is 117/min, respirations are 22/min, and oxygen saturation is 99% on room air. Physical exam is notable for an irritable, sweaty, and confused elderly man. Neurological exam reveals hyperreflexia of the lower extremities and clonus. Which of the following is the most likely etiology of this patient’s symptoms?", "answer": "Medication complication", "options": {"A": "Bacterial infection", "B": "Electrolyte abnormality", "C": "Medication complication", "D": "Substance withdrawal", "E": "Viral infection"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 36-year-old man presents to the physician with difficulty in breathing for 3 hours. There is no history of chest pain, cough or palpitation. He is a chronic smoker and underwent elective cholecystectomy one month back. There is no history of chronic or recurrent cough, wheezing or breathlessness. His temperature is 38.2°C (100.8°F), pulse is 108/min, blood pressure is 124/80 mm Hg, and respirations are 25/min. His arterial oxygen saturation is 98% in room air as shown by pulse oximetry. After a detailed physical examination, the physician orders a plasma D-dimer level, which was elevated. A contrast-enhanced computed tomography (CT) of the chest shows a filling defect in a segmental pulmonary artery on the left side. Which of the following signs is most likely to have been observed by the physician during the physical examination of this patient’s chest?", "answer": "Localized rales", "options": {"A": "Bilateral wheezing", "B": "Systolic murmur at the left sternal border", "C": "S3 gallop", "D": "Pleural friction rub", "E": "Localized rales"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2250-g (5.0-lb) male newborn and a 2900-g (6.4-lb) male newborn are delivered at 36 weeks' gestation to a 24-year-old, gravida 1, para 1 woman. The mother had no prenatal care. Examination of the smaller newborn shows low-set ears, retrognathia, and right-sided clubfoot. The hematocrit is 41% for the smaller newborn and 69% for the larger newborn. This pregnancy was most likely which of the following?", "answer": "Monochorionic-diamniotic monozygotic", "options": {"A": "Dichorionic-diamniotic monozygotic", "B": "Monochorionic-diamniotic monozygotic", "C": "Conjoined twins", "D": "Dichorionic-monoamniotic monozygotic", "E": "Monochorionic-monoamniotic monozygotic"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 54-year-old man presents to his primary care physician for back pain. His back pain worsens with standing for a prolonged period of time or climbing down the stairs and improves with sitting. Medical history is significant for hypertension, type II diabetes mellitus, and hypercholesterolemia. Neurologic exam demonstrates normal tone, 5/5 strength, and a normal sensory exam throughout the bilateral lower extremity. Skin exam is unremarkable and dorsalis pedis and posterior tibialis pulses are 3+. Which of the following is the best next step in management?", "answer": "MRI of the lumbosacral spine", "options": {"A": "Ankle-brachial index", "B": "MRI of the lumbosacral spine", "C": "Naproxen", "D": "Radiography of the lumbosacral spine", "E": "Surgical spinal decompression"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 11-month-old boy presents with the recent loss of appetite and inability to gain weight. His diet consists mainly of cow’s milk and fruits. Family history is unremarkable. Physical examination shows conjunctival pallor. Laboratory findings are significant for the following:\nHemoglobin 9.1 g/dL\nMean corpuscular volume 75 μm3\nMean corpuscular hemoglobin 20 pg/cell\nRed cell distribution width 18%\nThe patient is presumptively diagnosed with iron deficiency anemia (IDA) and ferrous sulfate syrup is prescribed. Which of the following laboratory values would most likely change 1st in response to this treatment?", "answer": "↑ reticulocyte count", "options": {"A": "Normalization of hemoglobin", "B": "↑ reticulocyte count", "C": "Anisocytosis", "D": "↓ mean corpuscular hemoglobin", "E": "↓ Mentzer index"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old woman presents to the office with a complaint of generalized weakness that has been getting worse over the last few months. She says that she just does not have the energy for her daily activities. She gets winded quite easily when she takes her dog for a walk in the evening. She says that her mood is generally ok and she gets together with her friends every weekend. She works as a teacher at a local elementary school and used to have frequent headaches while at work. Her husband is a commercial pilot and is frequently away for extended periods of time. Her only son is a sophomore in college and visits her every other week. She has had issues in the past with hypertension, but her blood pressure is currently well-controlled because she is compliant with her medication. She is currently taking atorvastatin and lisinopril. The blood pressure is 130/80 mm Hg, the pulse is 90/min, the temperature is 36.7°C (98.0°F), and the respirations are 16/min. On examination, she appears slightly pale and lethargic. Her ECG today is normal and recent lab work shows the following:\nSerum creatinine 1.5 mg/dL\nEstimated GFR 37.6 mL/min\nHemoglobin (Hb%) 9 mg/dL\nMean corpuscular hemoglobin (MCH) 27 pg\nMean corpuscular hemoglobin concentration (MCHC) 36 g/dL\nMean corpuscular volume (MCV) 85 fL\nReticulocyte count 0.1%\nErythrocyte count 2.5 million/mm3\nSerum iron 160 μg/dL\nSerum ferritin 150 ng/mL\nTotal iron binding capacity 105 μg/dL\nSerum vitamin B12 254 pg/mL\nSerum folic acid 18 ng/mL\nThyroid stimulating hormone 3.5 μU/mL\nWhich of the following will most likely help her?", "answer": "Start her on erythropoietin.", "options": {"A": "Start oral iron supplements.", "B": "Start her on fluoxetine.", "C": "Start her on erythropoietin.", "D": "Start vitamin B12 with folic acid.", "E": "Transfuse red blood cells."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old male undergoes a surveillance colonoscopy in which a 2 cm adenoma is identified and removed. Had this adenoma not been excised, the patient would have been at risk of progression to carcinoma. Which of the following is the final mutational step in the progression from adenoma to carcinoma?", "answer": "p53 inactivation", "options": {"A": "K-ras mutation", "B": "COX-2 overexpression", "C": "p53 inactivation", "D": "APC mutation", "E": "SMAD 2/4 loss"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old man is brought to the emergency department by his roommates for aggressive and unusual behavior. His roommates state that he has been under a lot of stress lately from his final exams and has been more reclusive. They state that this evening he was very irritable and was yelling at his computer prior to breaking it, followed by him spending several hours at the gym. His temperature is 101°F (38.3°C), blood pressure is 137/98 mmHg, pulse is 120/min, respirations are 23/min, and oxygen saturation is 99% on room air. Physical exam is notable for an irritable young man. Cardiopulmonary exam is notable for tachycardia and bilateral clear breath sounds. Neurological exam reveals dilated pupils. The patient is notably diaphoretic and speaks very rapidly during the physical exam and is aggressive. He is given haloperidol, diphenhydramine, and diazepam for sedation and placed in soft restraints. His symptoms resolved over the next 10 hours in the emergency department. Which of the following is the most likely diagnosis?", "answer": "Lisdexamfetamine intoxication", "options": {"A": "Caffeine intoxication", "B": "Cocaine intoxication", "C": "Lisdexamfetamine intoxication", "D": "Phencyclidine intoxication", "E": "Schizophrenia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 9-month-old boy is brought to the physician because of increased irritability, continual crying, and fever for 1 day. His mother has noticed that he refuses to lie down on his right side and keeps tugging at his right ear. One week ago, he had a runny nose that has since improved. He was born at term and has been otherwise healthy. He was exclusively breastfed until 2 months of age and is currently bottle-fed with some solid foods introduced. He has been attending a daycare center for the past 5 months. His temperature is 38.4°C (101.1°F) and pulse is 144/min. Otoscopic examination in this child is most likely to show which of the following?", "answer": "Bulging erythematous tympanic membrane", "options": {"A": "Bulging erythematous tympanic membrane", "B": "Retracted opacified tympanic membrane", "C": "Erythematous external auditory canal", "D": "Vesicles in the ear canal", "E": "Brown mass within the ear canal"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 11-year-old girl is brought to the office by her mother due to complaint of intermittent and severe periumbilical pain for 1 day. She does not have any significant past medical history. She provides a history of a recent school trip to the suburbs. On physical examination, there is a mild tenderness around the umbilicus without any distension or discharge. There is no rebound tenderness. Bowel sounds are normal. An abdominal imaging shows enlarged mesenteric lymph nodes, and she is diagnosed with mesenteric lymphadenitis. However, incidentally, a mass of tissue was seen joining the inferior pole of both kidneys as shown in the image. Which of the following is best describes this renal anomaly?", "answer": "Association with ureteropelvic junction obstruction (UPJO)", "options": {"A": "Fused kidneys ascend beyond superior mesenteric artery.", "B": "Increased risk of developing renal vein thrombosis", "C": "Association with ureteropelvic junction obstruction (UPJO)", "D": "Kidneys are usually non-functional.", "E": "Rapid progression to acute renal failure"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year-old man presents to the clinic for his annual physical examination. He was diagnosed with a rare arrhythmia a couple of years ago following an episode of dizziness. A mutation in the gene encoding for the L-type calcium channel protein was identified by genetic testing. He feels fine today. His vitals include: blood pressure 122/89 mm Hg, pulse 90/min, respiratory rate 14/min, and temperature 36.7°C (98.0°F). The cardiac examination is unremarkable. The patient has been conducting some internet research on how the heart works and specifically asks you about his own “ventricular action potential”. Which of the following would you expect to see in this patient?", "answer": "Abnormal phase 2", "options": {"A": "Abnormal phase 1", "B": "Abnormal phase 4", "C": "Abnormal phase 3", "D": "Abnormal phase 2", "E": "Abnormal phase 0"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old female has a history of periodic bloody diarrhea over several years. Colonoscopy shows sigmoid colon inflammation, and the patient complains of joint pain in her knees and ankles. You suspect inflammatory bowel disease. Which of the following would suggest a diagnosis of Crohn disease:", "answer": "Perianal fistula", "options": {"A": "Left lower quadrant pain", "B": "Jaundice", "C": "Loss of large bowel haustra", "D": "Mucosal and submucosal ulcerations", "E": "Perianal fistula"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 25-year-old man is in the middle of an ascent up a mountain, at an elevation of about 4,500 meters. This is the 4th day of his expedition. His friend notices that in the last few hours, he has been coughing frequently and appears to be short of breath. He has used his albuterol inhaler twice in the past 4 hours, but it does not seem to help. Within the past hour, he has coughed up some frothy, slightly pink sputum and is now complaining of nausea and headache. Other than his asthma, which has been well-controlled on a steroid inhaler, he is healthy. Which of the following is the most likely cause of this man’s symptoms?", "answer": "Non-cardiogenic pulmonary edema", "options": {"A": "Pulmonary embolism", "B": "Non-cardiogenic pulmonary edema", "C": "Acute heart failure", "D": "An acute asthma exacerbation", "E": "Pneumothorax"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Researchers are investigating the mechanism of cell apoptosis and host defense in mice. They have observed that mice with certain gene deletions are not able to fight the induced viral infection. They identify a cell that is able to destroy target cells infected with viruses by exocytosis of granule contents, which induces the activation of caspases. Which type of cell is responsible for this process?", "answer": "CD8+ lymphocytes", "options": {"A": "Macrophages", "B": "Neutrophils", "C": "CD8+ lymphocytes", "D": "CD4+ lymphocytes", "E": "Eosinophils"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-year-old boy is brought into your clinic by his mother for sunburns that have not been healing. The mother states that he easily gets sunburned. The mother admits she gave birth to him at home and has never taken him to see a doctor. The patient walks with a wide stance gait and appears unstable on his feet. He has an extensive erythematous, scaling, hyperkeratotic rash on his face, neck, arms and legs. After extensive workup, the patient is found to have a genetic disorder that results in defective absorption of an important vitamin. Which of the following is likely to be low if measured?", "answer": "Niacin", "options": {"A": "Niacin", "B": "Vitamin A", "C": "Vitamin K", "D": "Folate", "E": "Vitamin B12"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 12-year-old boy is brought to a psychiatrist by his mother upon referral from his pediatrician. The mother describes that for the past 2 years her son has experienced episodes of repetitive blinking and sudden jerking of the arms. Additionally, she notes that he often clears his throat and occasionally makes grunting noises. These symptoms have waxed and waned in frequency, but they have persisted for the past 2 years since they first developed. The patient is otherwise healthy without any coexisting medical issues. Which of the following agents would be effective at reducing the severity and frequency of this patient's current symptoms?", "answer": "Fluphenazine", "options": {"A": "Baclofen", "B": "Valproic acid", "C": "Fluphenazine", "D": "Sertraline", "E": "Gabapentin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 63-year-old woman comes to the physician because of worsening shortness of breath, cough, and a 4-kg (8.8-lb) weight loss over the last year. She has no history of serious illness and takes no medications. She has smoked one pack of cigarettes daily for 35 years. Her temperature is 37°C (98.6°F), pulse is 92/min, respirations are 20/min, blood pressure is 124/78 mm Hg, and pulse oximetry on room air shows an oxygen saturation of 93%. Physical examination shows decreased breath sounds. A flow-volume loop obtained via pulmonary function testing is shown. Which of the following is the most likely cause of this patient's respiratory symptoms?", "answer": "Chronic obstructive pulmonary disease", "options": {"A": "Chronic obstructive pulmonary disease", "B": "Idiopathic pulmonary fibrosis", "C": "Endotracheal neoplasm", "D": "Chronic asthma", "E": "Unilateral mainstem obstruction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old girl presents to the gynecologist's office due to lack of menarche. She has been sexually active with 1 male lifetime partner and always uses a condom. Her mother believes that breast development started at 11 years old. On exam, she is a well-appearing, non-hirsute teenager with Tanner V breast and pubic hair development. Her pelvic exam reveals normal external genitalia, a shortened vagina, and the cervix is unable to be visualized. Initial laboratory testing for hormone levels and karyotype is normal, and imaging confirms what you suspect on exam. What is the most likely cause of her lack of menstruation?", "answer": "Müllerian agenesis", "options": {"A": "5-alpha reductase deficiency", "B": "Androgen insensitivity", "C": "Müllerian agenesis", "D": "Premature ovarian failure", "E": "Turner syndrome"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 15-year-old boy is brought to the physician with an ongoing pruritic rash for 1 week. The rash is on his right forearm (refer to the image). He has not had a similar rash in the past. He has no history of allergies, and he is not taking any medications. He frequently enjoys gardening in their backyard. They have no household pets. The physical examination reveals no other abnormalities. Given the most likely diagnosis, which of the following is the most appropriate treatment of the condition described in this case?", "answer": "Topical clotrimazole", "options": {"A": "Oral acitretin", "B": "Oral terbinafine", "C": "Topical clotrimazole", "D": "Topical hydrocortisone", "E": "Topical salicylic acid"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl comes to the emergency department with a 5-day history of severe abdominal pain, cramping, nausea, and vomiting. She also has pain with urination. She is sexually active with one male partner, and they use condoms inconsistently. She experienced a burning pain when she last had sexual intercourse 3 days ago. Menses occur at regular 28-day intervals and last 5 days. Her last menstrual period was 3 weeks ago. Her temperature is 38.5°C (101.3°F), pulse is 83/min, and blood pressure is 110/70 mm Hg. Physical examination shows abdominal tenderness in the lower quadrants. Pelvic examination shows cervical motion tenderness and purulent cervical discharge. Laboratory studies show a leukocyte count of 15,000/mm3 and an erythrocyte sedimentation rate of 100 mm/h. Which of the following is the most likely diagnosis?", "answer": "Pelvic inflammatory disease", "options": {"A": "Pyelonephritis", "B": "Ectopic pregnancy", "C": "Ovarian cyst rupture", "D": "Appendicitis", "E": "Pelvic inflammatory disease"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old African American woman comes to the physician because of a 3-month history of increasing shortness of breath, cough, and intermittent fever. She works in a local factory that manufactures components for airplanes. She drinks 2–3 glasses of wine daily and has smoked half a pack of cigarettes daily for the past 5 years. Physical examination shows a purple rash on her cheeks and nose. An x-ray of the chest shows bilateral hilar adenopathy and a calcified nodule in the left lower lobe. A bronchoalveolar lavage shows a CD4:CD8 T-lymphocyte ratio of 10:1 (N=2:1). A biopsy of the nodule shows a noncaseating granuloma. Which of the following is the strongest predisposing factor for the development of this patient's condition?", "answer": "Race", "options": {"A": "Race", "B": "Exposure to beryllium", "C": "Alcohol consumption", "D": "Smoking", "E": "Exposure to acid-fast bacilli\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman visits her primary care provider with the results of a recent colonoscopy, which was ordered after 3 episodes of rectal bleeding in the last month. Her grandmother, mother, and sister all have been diagnosed with nonpolyposis colorectal cancer, at ages 65, 50, and 40 years, respectively. Colonoscopy for this patient revealed a large, flat, right-sided adenoma. Histopathological examination of the lesion showed villous histology and high-grade dysplasia. Which of the following helps explain the condition of this patient?", "answer": "Microsatellite instability", "options": {"A": "Chromosomal instability", "B": "Microsatellite instability", "C": "DNA hypermethylation", "D": "Chemical carcinogenicity", "E": "Environmental carcinogenicity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Two days after admission to the hospital, a 74-year-old man develops confusion and headache. He has also been vomiting over the past hour. His temperature is 36.7°C (98°F), pulse is 98/min, respirations are 22/min, and blood pressure is 140/80 mm Hg. He is lethargic and oriented only to person. Examination shows flushed skin. Fundoscopic examination shows bright red retinal veins. Serum studies show:\nNa+ 138 mEq/L\nK+ 3.5 mEq/L\nCl- 100 mEq/L\nHCO3- 17 mEq/L\nCreatinine 1.2 mg/dL\nUrea nitrogen 19 mg/dL\nLactate 8.0 mEq/L (N = 0.5 - 2.2 mEq/L)\nGlucose 75 mg/dL\nArterial blood gas analysis on room air shows a pH of 7.13. This patient's current presentation is most likely due to treatment for which of the following conditions?\"", "answer": "Hypertensive crisis", "options": {"A": "Alzheimer disease", "B": "Hypertensive crisis", "C": "Tension headache", "D": "Major depressive disorder", "E": "Acute dystonia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old Turkish female presents to your office for a routine examination. She recently started a new job and has been tired most of the time. She does not have any dizziness and has not lost consciousness. She follows a well-balanced diet and is not vegetarian. She recalls that other family members have had similar symptoms in the past. On physical exam her temperature is 99°F (37.2°C), blood pressure is 115/78 mmHg, pulse is 100/min, respirations are 22/min, and pulse oximetry is 99% on room air. On physical exam, you notice conjunctival pallor. Labs are obtained and the results are shown below:\n\nHemoglobin: 10.2 g/dL\nHematocrit: 34%\nLeukocyte count: 5,000 cells/mm^3 with normal differential\nPlatelet count: 252,000/mm^3\nMean corpuscular hemoglobin concentration: 20.4%\nMean corpuscular volume: 65 µm^3\n\nPeripheral blood smear is shown in the image provided. The cause of her anemia is most likely associated with which of the following?", "answer": "Point mutation on chromosome 11", "options": {"A": "Point mutation on chromosome 11", "B": "X-linked defect in ALA synthase", "C": "Inhibition of ALA dehydratase", "D": "Blood loss", "E": "Malnutrition"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old man is brought to the emergency department by his wife because of a 1-hour history of confusion and strange behavior. She reports that he started behaving in an agitated manner shortly after eating some wild berries that they had picked during their camping trip. His temperature is 38.7°C (101.7°F). Physical examination shows warm, dry skin and dry mucous membranes. His pupils are dilated and minimally reactive to light. His bowel sounds are decreased. The patient is admitted and pharmacotherapy is initiated with a drug that eventually results in complete resolution of all of his symptoms. This patient was most likely administered which of the following drugs?", "answer": "Physostigmine", "options": {"A": "Scopolamine", "B": "Rivastigmine", "C": "Atropine", "D": "Physostigmine", "E": "Neostigmine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old G1 is brought to the emergency department because of sharp pains in her abdomen. She is at 30 weeks gestation based on ultrasound. She complains of  feeling a little uneasy during the last 3 weeks of her pregnancy. She mentions that her abdomen has not been enlarging as expected and her baby is not moving as much as during the earlier part of the pregnancy. If anything, she noticed her abdomen has decreased in size. While she is giving her history, the emergency medicine physician notices that she is restless and is sweating profusely. An ultrasound is performed and her blood is sent for type and match. The blood pressure is 90/60 mm Hg, the pulse is 120/min, and the respiratory rate  is 18/min. The fetal ultrasound is significant for no fetal heart motion or fetal movement. Her blood work shows the following: hemoglobin, 10.3 g/dL; platelet count, 1.1*10(5)/ml; bleeding time, 10 minutes; PT, 25 seconds; and PTT, 45 seconds. Which of the following would be the best immediate course of management for this patient?", "answer": "IV fluids", "options": {"A": "IV fluids", "B": "Initiation of labor", "C": "D-dimer assay", "D": "Fresh frozen plasma", "E": "Low-molecular-weight heparin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old G1P0 woman presents to the labor and delivery ward at 39 weeks gestation for elective induction of labor. She requests a labor epidural. An epidural catheter is secured at the L4-L5 space. She exhibits no hemodynamic reaction to lidocaine 1.5% with epinephrine 1:200,000. A continuous infusion of bupivacaine 0.0625% is started. After 5 minutes, the nurse informs the anesthesiologist that the patient is hypotensive to 80/50 mmHg with a heart rate increase from 90 bpm to 120 bpm. The patient is asymptomatic and fetal heart rate has not changed significantly from baseline. She says that her legs feel heavy but is still able to move them. What is the most likely cause of the hemodynamic change?", "answer": "Sympathetic blockade", "options": {"A": "Bainbridge reflex", "B": "Intrathecal infiltration of local anesthetic", "C": "Local anesthetic systemic toxicity", "D": "Spinal anesthesia", "E": "Sympathetic blockade"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 39-year-old woman presents to her gynecologist for a routine visit. She has no complaints during this visit. She had an abnormal pap test 6 years ago that showed atypical squamous cells of undetermined significance. The sample was negative for human papillomavirus. On her follow-up Pap test 3 years later, there was no abnormality. The latest pap test results show atypical glandular cells with reactive changes in the cervical epithelium. The gynecologist decides to perform a colposcopy, and some changes are noted in this study of the cervical epithelium. The biopsy shows dysplastic changes in the epithelial cells. Which of the following is the next best step in the management of this patient?", "answer": "Cold knife conization", "options": {"A": "Loop electrosurgical excision procedure", "B": "Cold knife conization", "C": "Follow-up pap smear in one year", "D": "Follow-up pap smear in 3 years", "E": "Repeat colposcopy in 6 months"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 64-year-old nulliparous woman comes to the physician because of fatigue and an increase in abdominal girth despite a 5-kg (11.0-lb) weight loss over the past 6 months. Her last Pap smear 2 years ago showed atypical squamous cells of undetermined significance; subsequent HPV testing was negative at that time. Menarche was at the age of 10 years and her last menstrual period was 6 years ago. Abdominal examination shows shifting dullness. There is tenderness to palpation of the left lower quadrant but no guarding or rebound. Bimanual palpation shows a small uterus and a left adnexal mass. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Elevated serum CA-125 level", "options": {"A": "Elevated serum beta-hCG level", "B": "Proliferation of endometrial glands", "C": "Chocolate cyst of the left ovary", "D": "Elevated serum CA-125 level", "E": "Cervical dysplasia on cervical smear"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old boy comes to the emergency department following an injury during football practice. He fell and landed on the lateral aspect of his right shoulder. He is holding his right arm supported by his left arm, with his right arm adducted against his side. He is tender to palpation directly over the middle third of his clavicle. Radiographs reveal a non-displaced fracture of the middle third of the clavicle. Which of the following is the most appropriate treatment at this time?", "answer": "Figure-of-eight splinting", "options": {"A": "Open reduction and internal fixation with a compression plate", "B": "Open reduction and internal fixation with an intramedullary nail", "C": "Open reduction and internal fixation with lag screws", "D": "Figure-of-eight splinting", "E": "Mobilization"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old man comes to the physician for a routine health maintenance examination. He was diagnosed with HIV 8 years ago. He is currently receiving triple antiretroviral therapy. He is sexually active and uses condoms consistently. He is planning a trip to Thailand with his partner to celebrate his 35th birthday in 6 weeks. His last tetanus and diphtheria booster was given 4 years ago. He received three vaccinations against hepatitis B 5 years ago. He had chickenpox as a child. Other immunization records are unknown. Vital signs are within normal limits. Cardiopulmonary examination shows no abnormalities. Leukocyte count shows 8,700/mm3, and CD4+ T-lymphocyte count is 480 cells/mm3 (Normal ≥ 500); anti-HBs is 150 mIU/mL. Which of the following recommendations is most appropriate at this time?", "answer": "Measles, mumps, rubella vaccine", "options": {"A": "Hepatitis B vaccine", "B": "Bacillus Calmette Guerin vaccine", "C": "Measles, mumps, rubella vaccine", "D": "Yellow fever vaccine", "E": "No vaccination"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old man comes to the emergency department for severe eye pain. The patient reports that he is a construction worker and was drilling metal beams when he suddenly felt a sharp pain in his right eye. Since then, the vision in his right eye has seemed blurry and his eye “has not stopped tearing.” The patient’s medical history is significant for type II diabetes mellitus and hypertension. His medications include metformin, captopril, and lovastatin. He has a mother with glaucoma, and both his brother and father have coronary artery disease. Upon physical examination, there is conjunctival injection present in the right eye with no obvious lacerations to the eyelids or defects in extraocular eye movements. Pupils are equal and reactive to light. No afferent pupillary defect is appreciated. The unaffected eye has 20/20 visual acuity. The patient refuses to participate in the visual acuity exam of the right eye due to pain. Which of the following is the best initial step in management?", "answer": "Fluorescein stain", "options": {"A": "Fluorescein stain", "B": "Orbital magnetic resonance imaging", "C": "Patching", "D": "Tonometry", "E": "Topical corticosteroids"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 49-year-old man comes to the hospital for a 10-day history of cough and worsening shortness of breath. He has sharp right-sided chest pain that worsens on inspiration and coughing. Two weeks ago, the patient was admitted to the hospital after passing out on the street from alcohol intoxication but he left against medical advice. He has coronary artery disease and hypertension, and he does not take any medications. He drinks 4 cans of beer daily and has smoked 2 packs of cigarettes daily for 20 years. His temperature is 38.5°C (101.3° F), pulse is 110/min, respirations are 29/min, and blood pressure is 110/65 mmHg. Examination shows poor dentition. There is dullness to percussion at the base of the right lung. Crackles and markedly decreased breath sounds are heard over the right middle and lower lung fields. An x-ray of the chest shows a right-sided loculated pleural effusion and consolidation of the surrounding lung with visible air bronchogram; there are no rib fractures. Thoracocentesis is performed. Examination of this patient's pleural fluid is most likely to show which of the following findings?", "answer": "Glucose of 30 mg/dL", "options": {"A": "Amylase of 200 U/L", "B": "Lymphocytosis of > 90%", "C": "Pleural fluid LDH/serum LDH ratio of 0.5", "D": "Lactate dehydrogenase of 45 U/L", "E": "Glucose of 30 mg/dL"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 70-year-old Caucasian women presents to the emergency department complaining of abdominal pain. She is oriented to person but is slow to answer questions and cannot name her location. She is afebrile on exam and endorses mild suprapubic tenderness. Her urine culture was positive for leukocyte esterase and nitrites. She was prescribed appropriate treatments. On follow-up, she complains of a new rash. In the past few days she has noticed that her skin becomes very red and more easily sunburns. Per the patient, her symptoms have resolved and her initial infection has cleared. Which of the following antibiotics was most likely prescribed to this patient?", "answer": "Trimethoprim-sulfamethoxazole", "options": {"A": "Nitrofurantoin", "B": "Cephalexin", "C": "Azithromycin", "D": "Trimethoprim-sulfamethoxazole", "E": "Ceftriaxone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 26-year-old man is brought to the emergency department because of extreme agitation and confusion. He is unable to give a clear history. His mother says he returned from a hiking trip 4 weeks ago on which he also explored caves. Over the past few days, he has had generalized fever and malaise with a sore throat. He has refused to drink any liquids for the last day. His immunizations are up-to-date. His temperature is 100.6°F (38.1°C), pulse is 92/min, respirations are 18/min, and blood pressure is 110/75 mm Hg. His pupils are 6 mm wide and reactive to light. He has a moderate amount of drool. Muscle tone is greatly increased in both the upper and lower extremities. The remainder of the examination is not performed because the patient becomes combative and refuses further assessment. Serum and urine toxicology screens are negative. Which of the following is most likely to have prevented this patient's condition?", "answer": "Immunoglobulin and vaccination administration", "options": {"A": "Corticosteroid therapy", "B": "Plasmapheresis", "C": "Antifungal therapy", "D": "Antiviral therapy", "E": "Immunoglobulin and vaccination administration"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old woman with a history of bipolar disorder presents to her psychiatrist’s office for a follow-up appointment. She says she is doing better on the new drug she was prescribed. However, she recently noticed that she is drinking a lot of water and urinates more frequently throughout the day. She also says there are moments recently when she feels confused and agitated. Her vitals include: blood pressure 122/89 mm Hg, temperature 36.7°C (98.0°F), pulse 88/min and respirations 18/min. Her physical examination is within normal limits. Which of the following drugs was she most likely prescribed?", "answer": "Lithium", "options": {"A": "Lithium", "B": "Amitriptyline", "C": "Valproic acid", "D": "Carbamazepine", "E": "Chlorpromazine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old man presents to the physician with complaint of fever and non-bloody diarrhea for the past 3 days, after a week of constipation. He and his family recently returned from a summer spent in New Delhi, India visiting relatives. Physical examination reveals abdominal tenderness and a pink macular rash extending from his trunk to his upper arms. His vital signs are as follows: temperature is 99.7°F (37.6°C), blood pressure is 120/72 mmHg, pulse is 85/min, and respirations are 16/min. Which of the following drugs would be most effective in treating this patient’s condition?", "answer": "Ciprofloxacin", "options": {"A": "Ciprofloxacin", "B": "Metronidazole", "C": "Oral rehydration solution", "D": "Oral vancomycin", "E": "Penicillin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 13-year-old boy is brought to his pediatrician for evaluation of leg pain. Specifically, he has been having pain around his right knee that has gotten progressively worse over the last several months. On presentation, he has swelling and tenderness over his right distal femur. Radiographs are obtained and the results are shown in figure A. His family history is significant in that several family members also had this disorder and others had pathology in the eye near birth. The patient is referred for a genetic consult, and a mutation is found on a certain chromosome. The chromosome that is most likely affected also contains a gene that is associated with which of the following pathologies?", "answer": "Breast cancer", "options": {"A": "Breast cancer", "B": "Colorectal cancer", "C": "Neurofibromas", "D": "Pancreatic cancers", "E": "Soft tissue sarcomas"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-month-old Middle Eastern female infant from a consanguinous marriage presents with seizures, anorexia, failure to thrive, developmental delay, and vomiting and fatigue after eating. Blood work demonstrated levels of methylmalonic acid nearly 500 times normal levels. A carbon-14 propionate incorporation assay was performed on the fibroblasts of the patient and compared to a healthy, normal individual. Little to none of the radiolabeled carbons of the propionate appeared in any of the intermediates of the Krebs cycle. Which of the following reactions is not taking place in this individual?", "answer": "Methylmalonyl-CoA --> Succinyl-CoA", "options": {"A": "Propionyl-CoA --> Methylmalonyl-CoA", "B": "Acetyl-CoA + CO2 --> Malonyl-CoA", "C": "Methylmalonyl-CoA --> Succinyl-CoA", "D": "Pyruvate --> acetyl-CoA", "E": "Acetyl-CoA + Oxaloacetate --> Citrate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman with a history of polycystic ovarian syndrome, depression, and chronic bilateral ear infections presents to the otolaryngologist's clinic 12 weeks after right ear tympanoplasty. Her audiology report one week prior showed that her hearing improved as expected by 20 decibels. However, she reports that she has occasional shooting pain with eating and when she wears earrings. She states that she has a stressful job as a cashier at the local department store and often sleeps poorly. She denies any neck pain or tenderness when she washes her face. On physical exam, no tenderness is elicited with preauricular or mandibular palpation bilaterally. No jaw clicking is heard. Right postauricular tapping causes tenderness in her right tonsillar area. Her molar teeth appear even and symmetric bilaterally. Her uvula is midline and her gag reflex is intact. What is the most likely diagnosis?", "answer": "Glossopharyngeal neuralgia", "options": {"A": "Atypical migraine", "B": "Bruxism", "C": "Cluster headache", "D": "Glossopharyngeal neuralgia", "E": "Trigeminal neuralgia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 14-month-old boy is brought in by his parents with an 8-month history of diarrhea, abdominal tenderness and concomitant failure to thrive. The pediatric attending physician believes that Crohn’s disease is the best explanation of this patient’s symptoms. Based on the pediatric attending physician’s experience, the pretest probability of this diagnosis is estimated at 40%. According to Fagan nomogram (see image). If the likelihood ratio of a negative test result (LR-) for Crohn’s disease is 0.04, what is the chance that this is the correct diagnosis in this patient with a negative test result?", "answer": "2.5%", "options": {"A": "2.5%", "B": "25%", "C": "40%", "D": "75%", "E": "97.5%"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old woman with a history of osteoarthritis and hypertension presents to the office complaining of persistent abdominal pain for the last 2 months. She describes the pain as 'burning and achy' that is worse when she eats, which has lead to a weight loss of 4.5 kg (10.0 lb). The patient is currently taking lisinopril and atenolol for her blood pressure and ibuprofen as needed for her osteoarthritis. Her temperature is 37.1°C (98.7°F), heart rate is 75/min, and blood pressure is 120/80 mm Hg. An endoscopy is performed and a gastric ulcer is visualized and biopsied. The biopsy reveals H. pylori infection. Which of the following is the most likely predisposing factor to this patient’s diagnosis?", "answer": "Chronic NSAID use", "options": {"A": "Chronic NSAID use", "B": "Longstanding GERD", "C": "Adverse effect of beta-blockers", "D": "Age and gender", "E": "A congenital diverticulum"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old male patient with chronic alcoholism presents to an ambulatory medical clinic, where the hepatologist elects to perform comprehensive hepatitis B screening, in addition to several other screening and preventative measures. Given the following choices, which serologic marker, if positive, would indicate the patient’s immunity to the hepatitis B virus?", "answer": "HBsAb", "options": {"A": "HBsAg", "B": "HBsAb", "C": "HBcAb", "D": "HBeAg", "E": "HBeAb"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old man comes to the physician because of chronic fatigue and generalized weakness after exertion. His legs feel stiff after walking long distances and he has leg cramps after climbing stairs. His symptoms are always relieved by rest. Urine dipstick shows 3+ blood and urinalysis is negative for RBCs. Baseline venous lactate and serum ammonia levels are collected, after which a blood pressure cuff is attached to the upper right arm. The patient is asked to continuously pump his right arm with the cuff inflated and additional venous samples are collected at 2-minute intervals. Analysis of the venous blood samples shows that, over time, serum ammonia levels increase and venous lactate levels remain stable. A biopsy of the right gastrocnemius muscle will most likely show which of the following?", "answer": "Subsarcolemmal acid–Schiff-positive deposits", "options": {"A": "Intrafascicular CD8+ lymphocytic infiltration", "B": "Endomysial fibrosis with absent dystrophin", "C": "Intermyofibrillar proliferation of mitochondria", "D": "Subsarcolemmal acid–Schiff-positive deposits", "E": "Perivascular CD4+ lymphocytic infiltrate"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old man comes to the physician because of a painful, burning red rash on his face and hands, which developed 30 minutes after going outside to do garden work. He wore a long-sleeved shirt and was exposed to direct sunlight for about 10 minutes. The patient is light-skinned and has a history of occasional sunburns when he does not apply sunscreen. The patient was diagnosed with small cell lung carcinoma 2 months ago and is currently undergoing chemotherapy. He is currently taking demeclocycline for malignancy-associated hyponatremia and amoxicillin for sinusitis. He has also had occasional back pain. He takes zolpidem and drinks 1–2 glasses of brandy before going to sleep every night. He has smoked a pack of cigarettes daily for 20 years. His pulse is 72/min and his blood pressure is 120/75 mm Hg. Physical examination shows prominent erythema on his forehead, cheeks, and neck. Erythema and papular eruptions are seen on the dorsum of both hands. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Use of demeclocycline", "options": {"A": "Adverse reaction to amoxicillin", "B": "Uroporphyrin accumulation", "C": "Systemic lupus erythematosus", "D": "Use of demeclocycline", "E": "Normal sunburn reaction\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 44-year-old man is brought to the emergency department 25 minutes after falling off the roof of a house. He was cleaning the roof when he slipped and fell. He did not lose consciousness and does not have any nausea. On arrival, he is alert and oriented and has a cervical collar on his neck. His pulse is 96/min, respirations are 18/min, and blood pressure is 118/78 mm Hg. Examination shows multiple bruises over the forehead and right cheek. The pupils are equal and reactive to light. There is a 2-cm laceration below the right ear. Bilateral ear canals show no abnormalities. The right wrist is swollen and tender; range of motion is limited by pain. The lungs are clear to auscultation. There is no midline cervical spine tenderness. There is tenderness along the 2nd and 3rd ribs on the right side. The abdomen is soft and nontender. Neurologic examination shows no focal findings. Two peripheral venous catheters are placed. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the cervical spine", "options": {"A": "X-ray of the chest", "B": "X-ray of the neck", "C": "CT scan of the cervical spine", "D": "Focused Assessment with Sonography in Trauma", "E": "X-ray of the right wrist\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 63-year-old man presents to his primary care physician because he has been having headaches and hearing loss. In addition, he says that he has been having difficulty opening his jaw to eat and recurrent middle ear infections. Physical exam reveals enlarged neck lymph nodes and a mass in the nasopharynx. Biopsy of the mass reveals undifferentiated squamous epithelial cells. The organism that is most likely associated with this patient's disease is also associated with which of the following disorders?", "answer": "Burkitt lymphoma", "options": {"A": "Adult T-cell lymphoma", "B": "Burkitt lymphoma", "C": "Heptaocellular carcinoma", "D": "Kaposi sarcoma", "E": "Vulvar carcinoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old nurse presents 12 hours after she accidentally stuck herself with a blood-contaminated needle. She reported the accident appropriately and now seeks post-exposure prophylaxis. She does not have any complaints at the moment of presentation. Her vital signs include: blood pressure 125/80 mm Hg, heart rate 71/min, respiratory rate 15/min, and temperature 36.5℃ (97.7℉). Physical examination is unremarkable. The nurse has prescribed a post-exposure prophylaxis regimen which includes tenofovir, emtricitabine, and raltegravir. How will tenofovir change the maximum reaction rate (Vm) and Michaelis constant (Km) of the viral reverse transcriptase?", "answer": "Vm will stay the same, Km will increase", "options": {"A": "Vm will decrease, Km will stay the same", "B": "Vm and Km will both decrease", "C": "Vm will decrease, Km will increase", "D": "Vm will stay the same, Km will increase", "E": "Vm and Km will both increase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man, who underwent a kidney transplant 2 years ago, presents in septic shock. He is compliant with his immunosuppressive therapy. He does not use any drugs and is sexually active with one male partner. His complete blood count returns as follows: Hemoglobin: 13.7 g/dL, white blood cell count: 4000 cells/microliter, platelets 250,000 cells/microliter. Of note, from his differential: neutrophils: 10%, lymphocytes: 45%, and monocytes: 7%. His basic metabolic profile is notable for a creatinine remaining at his baseline of 0.9 mg/dL. The patient is started on broad spectrum antibiotics, but his condition does not improve. Fungal blood cultures are obtained and grow Candida species. Which of the following was the most-likely predisposing factor?", "answer": "Decreased phagocytic cell count", "options": {"A": "Defective IL-2 receptor", "B": "Decreased phagocytic cell count", "C": "HIV infection", "D": "Failure to take suppressive trimethoprim/sulfamethoxazole therapy", "E": "Renal failure"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "One day after doctors helped a 28-year-old primigravid woman deliver a 4700 g (10 lb 6 oz) boy, he has bluish discoloration of his lips and fingernails. Oxygen saturation on room air is 81%. Examination shows central cyanosis. A continuous machine-like murmur is heard over the left upper sternal border. A single S2 heart sound is present. Supplemental oxygen does not improve the cyanosis. Echocardiography shows the pulmonary artery arising from the posterior left ventricle and the aorta arising from the right ventricle with active blood flow between the right and left ventricles. Further evaluation of the mother is most likely to show which of the following?", "answer": "Elevated fasting blood glucose", "options": {"A": "Elevated fasting blood glucose", "B": "Positive rapid plasma reagin test", "C": "Prenatal alcohol use", "D": "Prenatal lithium intake", "E": "Prenatal phenytoin intake"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old man with chronic obstructive lung disease, depression, and type 2 diabetes mellitus comes to the physician with fever, chills, dyspnea, and a productive cough for 5 days. His temperature is 38.8°C (101.8°F) and respirations are 30/min. An x-ray of the chest shows a right lower lobe infiltrate, and sputum culture grows bacteria that are sensitive to fluoroquinolone antibiotics. Pharmacotherapy with oral moxifloxacin is initiated. Three days later, the patient continues to have symptoms despite being compliant with the antibiotic. Serum moxifloxacin levels are undetectable. The lack of response to antibiotic therapy in this patient is most likely due to the concurrent ingestion of which of the following medications?", "answer": "Multivitamin", "options": {"A": "Amitryptyline", "B": "Multivitamin", "C": "Glimepiride", "D": "Theophylline", "E": "Prednisone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 75-year-old over-weight gentleman with a long history of uncontrolled hypertension, diabetes, smoking and obesity is presenting to his primary care physician with a chief complaint of increased difficulty climbing stairs and the need to sleep propped up by an increasing number of pillows at night. On physical examination the patient has an extra heart sound just before S1 heard best over the cardiac apex and clear lung fields. The EKG and chest x-ray are attached (Figures A and B respectively). What is the largest contributor to this patient's symptoms?", "answer": "Uncontrolled Hypertension", "options": {"A": "Long-term smoking", "B": "Uncontrolled Hypertension", "C": "Obesity", "D": "Sleep Apnea", "E": "Acute Myocardial Infarction"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 18-month-old boy presents to the pediatrician by his mother for a routine check-up. The mother has no concerns, although she asks about the \"hole in his heart\" that the patient had at birth. The patient has no history of cyanosis or heart failure; however, a holosystolic, harsh murmur was noted at the 3- and 6-month check-ups. On examination, the patient is playful and alert. He has met all developmental milestones. The cardiac examination reveals a regular rate and rhythm with persistence of the holosystolic, harsh murmur. What is the most likely cause of the murmur in this child?", "answer": "Defect of the membranous interventricular septum", "options": {"A": "Defect of muscular interventricular septum", "B": "Patent foramen ovale", "C": "Defect of the membranous interventricular septum", "D": "Defective dynein functioning", "E": "Failure of endocardial cushion to form"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-month-old boy is brought to his pediatrician for a well-child visit. His parents have noticed that he has had poor growth compared to his older siblings. The boy was delivered vaginally after a normal pregnancy. His temperature is 98.8°F (37.1°C), blood pressure is 98/68 mmHg, pulse is 88/min, and respirations are 20/min. On exam, his abdomen appears protuberant, and the boy appears to have abnormally enlarged cheeks. A finger stick reveals that the patient’s fasting blood glucose is 50 mg/dL. On further laboratory testing, the patient is found to have elevated blood lactate levels, as well as no response to a glucagon stimulation test. What enzymatic defect is most likely present?", "answer": "Glucose-6-phosphatase", "options": {"A": "Alpha-1,4-glucosidase", "B": "Alpha-1,6-glucosidase", "C": "Glucose-6-phosphatase", "D": "Glycogen phosphorylase", "E": "Glycogen synthase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-month-old boy is brought to the clinic with a history of recurrent episodes of stridor and wheezing. His mother reports that his wheezing is exacerbated by crying, feeding, and flexion of the neck, and is relieved by extension of the neck. Occasionally he vomits after feeding. What is the most likely diagnosis?", "answer": "Double aortic arch", "options": {"A": "Gastroesophageal reflux disease", "B": "Laryngomalacia", "C": "Double aortic arch", "D": "Congenital subglottic stenosis", "E": "Recurrent viral wheeze"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old nulliparous woman presents to her gynecologist complaining of recurrent menstrual pain. She reports a 4-month history of pelvic pain that occurs during her periods. It is more severe than her typical menstrual cramps and sometimes occurs when she is not on her period. She also complains of pain during intercourse. Her periods occur every 28-30 days. Her past medical history is notable for kyphoscoliosis requiring spinal fusion and severe acne rosacea. She takes trans-tretinoin and has a copper intra-uterine device. Her family history is notable for ovarian cancer in her mother and endometrial cancer in her paternal grandmother. Her temperature is 99°F (37.2°C), blood pressure is 120/85 mmHg, pulse is 90/min, and respirations are 16/min. On exam, she appears healthy and is in no acute distress. A bimanual examination demonstrates a normal sized uterus and a tender right adnexal mass. Her intrauterine device is well-positioned. What is the underlying cause of this patient’s condition?", "answer": "Endometrial glands and stroma within the peritoneal cavity", "options": {"A": "Benign proliferation of uterine myometrium", "B": "Chronic inflammation of the uterine endometrium", "C": "Endometrial glands and stroma within the peritoneal cavity", "D": "Endometrial glands and stroma within the uterine myometrium", "E": "Excess androgen production"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Urinalysis shows:\nProtein 1+\nLeukocyte esterase positive\nNitrite positive\nRBC 2/hpf\nWBC 90/hpf\nWBC casts numerous\nWhich of the following is the most appropriate next step in management?\"", "answer": "Treat on an outpatient basis with ciprofloxacin", "options": {"A": "Treat on an outpatient basis with nitrofurantoin", "B": "Admit the patient and perform an CT scan of the abdomen", "C": "Treat on an outpatient basis with ciprofloxacin", "D": "Admit the patient and treat with intravenous levofloxacin", "E": "Wait for culture results and treat accordingly"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Two days after hospitalization for urgent chemotherapy to treat Burkitt’s lymphoma, a 7-year-old boy develops dyspnea and reduced urine output. He also feels a tingling sensation in his fingers and toes. Blood pressure is 100/65 mm Hg, respirations are 28/min, pulse is 100/min, and temperature is 36.2°C (97.2°F). The lungs are clear to auscultation. He has excreted 20 mL of urine in the last 6 hours. Laboratory studies show:\nHemoglobin 15 g/dL\nLeukocyte count 6,000/mm3 with a normal differential serum\nK+ 6.5 mEq/L\nCa+ 7.6 mg/dL\nPhosphorus 5.4 mg/dL\nHCO3− 15 mEq/L\nUric acid 12 mg/dL\nUrea nitrogen 44 mg/dL\nCreatinine 2.4 mg/dL\nArterial blood gas analysis on room air:\npH 7.30\nPCO2 30 mm Hg\nO2 saturation 95%\nWhich of the following is most likely to have prevented this patient’s condition?", "answer": "Allopurinol", "options": {"A": "Allopurinol", "B": "Ciprofloxacin", "C": "Pneumococcal polysaccharide vaccine", "D": "Sodium bicarbonate", "E": "No prevention would have been effective"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old woman comes to the emergency room because she had difficulty breathing during an exercise session. She also has a cough and end-expiratory wheezing. Besides these symptoms, she has a normal physical appearance. She has experienced similar breathing problems during exercise in the past, but never during rest. She is afebrile. What is the best treatment in this case?", "answer": "Short acting β2-agonists", "options": {"A": "Systemic corticosteroids", "B": "Short acting β2-agonists", "C": "Aminophylline", "D": "No therapy, only avoidance of exercise", "E": "Long acting β2-agonists"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old man comes to the physician because of a 1-day history of right-sided facial weakness and sound intolerance. Three days ago, he hit the right side of his head in a motor vehicle collision. He neither lost consciousness nor sought medical attention. Physical examination shows drooping of the mouth and ptosis on the right side. Sensation over the face is not impaired. Impedance audiometry shows an absence of the acoustic reflex in the right ear. Which of the following muscles is most likely paralyzed in this patient?", "answer": "Stylohyoid", "options": {"A": "Tensor tympani", "B": "Stylopharyngeus", "C": "Cricothyroid", "D": "Anterior belly of the digastric", "E": "Stylohyoid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to the emergency department by his mother for the evaluation of abdominal pain for one hour after drinking a bottle of toilet bowl cleaner. The mother reports that he vomited once on the way to the hospital and his vomit was non-bloody. The patient has pain with swallowing. He appears uncomfortable. Pulse oximetry shows an oxygen saturation of 82%. Examination shows heavy salivation. Oral examination shows mild oral erythema and in the area of the epiglottis, but no burns. An x-ray of the chest shows no abnormalities. The patient is admitted to the intensive care unit. He is intubated and oxygenation and intravenous fluid resuscitation are begun. All contaminated clothes are removed. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Obtain upper endoscopy", "options": {"A": "Obtain upper endoscopy", "B": "Perform gastric lavage", "C": "Dilute the ingested agent", "D": "Obtain barium upper gastrointestinal series", "E": "Administer activated charcoal"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 31-year-old female presents to her gynecologist with spotting between periods. She reports that her menses began at age 11, and she has never had spotting prior to the three months ago. Her medical history is significant for estrogen-receptor positive intraductal carcinoma of the breast, which was treated with tamoxifen. An endometrial biopsy is performed, which shows endometrial hyperplasia with atypia. She reports that she and her husband are currently trying to have children. What is the next best step?", "answer": "Start progestin-only therapy", "options": {"A": "Total abdominal hysterectomy with bilateral salpingoopherectomy", "B": "Partial, cervix-sparing hysterectomy", "C": "Start combination estrogen and progestin therapy", "D": "Start progestin-only therapy", "E": "Observation with annual endometrial biopsies"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old man comes to the physician because of generalized fatigue for the past 3 months. During this time, his grades have declined in his college courses because he has had difficulty focusing on assignments and sometimes sleeps in class. He no longer plays the drums for his band and has stopped attending family events. His temperature is 37°C (98.6°F), pulse is 60/min, and blood pressure is 130/80 mm Hg. Physical examination shows no abnormalities. On mental status examination, he describes his mood as “ok.” He has a flat affect. There is no evidence of suicidal ideation. His speech is slow in rate and monotone in rhythm, and his thought process is organized. He has no delusions or hallucinations. Which of the following is the most appropriate next step in treatment?", "answer": "Escitalopram therapy", "options": {"A": "Escitalopram therapy", "B": "Reassurance", "C": "Phenelzine therapy", "D": "Diazepam therapy", "E": "Amitriptyline therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 67-year-old African American woman visits the clinic with a complaint of progressive fatigue. These symptoms started gradually and slowly became worse over the past 4 months. She is short of breath after walking a few blocks and has difficulty climbing stairs. She denies having chest pain, leg swelling, or a cough. Her past medical history is significant for osteoporosis and gastroesophageal reflux disease. She takes omeprazole as needed and daily baby aspirin. She is a retired accountant and is a lifetime nonsmoker but she drinks a small glass of red wine every night before bed. Her diet is varied. Today, her blood pressure is 128/72 mm Hg, heart rate is 105/min, respiratory rate is 22/min, temperature 37.0°C (98.6°F) and oxygen saturation is 94% on room air. On physical examination, she has marked conjunctival pallor. Cardiac auscultation reveals a rapid heartbeat with a regular rhythm and a 2/6 systolic murmur over the right upper sternal border. Lungs are clear to auscultation bilaterally and abdominal examination was within normal limits. Peripheral blood smear shows microcytic, hypochromic red blood cells. The following laboratory values are obtained:\nHematocrit 29%\nHemoglobin 9.8 mg/dL\nMean red blood cell volume 78 fL\nPlatelets 240,000/mm3\nWhich of the following will most likely be present in this patient?", "answer": "A decrease in her reticulocyte count", "options": {"A": "An increase in her reticulocyte count", "B": "A decrease in her reticulocyte count", "C": "A decrease in erythropoietin levels ", "D": "Increased white blood cell count", "E": "Thrombocytopenia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-day old male newborn delivered vaginally at 36 weeks to a 29-year-old woman, gravida 3, para 2, has generalized convulsions lasting 2 minutes. Previous to the event, he had difficulty feeding and was lethargic. Pregnancy and delivery were uncomplicated. Apgar scores were 7 and 8 at 1 and 5 minutes, respectively. Pregnancy and delivery of the mother's first 2 children were also uncomplicated. Medications of the mother include folic acid and a multivitamin. The mother's immunizations are up-to-date. The infant appears icteric. His vital signs are within normal limits. The infant's weight and length are at the 5th percentile, and his head circumference at the 99th percentile for gestational age. There are several purpura of the skin. Ocular examination shows posterior uveitis. The patient does not pass his auditory screening tests. Cranial ultrasonography shows ventricular dilatation, as well as hyperechoic foci within the cortex, basal ganglia, and periventricular region. Which of the following is the most likely diagnosis?", "answer": "Congenital toxoplasmosis", "options": {"A": "Congenital toxoplasmosis", "B": "Congenital rubella infection", "C": "Congenital syphilis infection", "D": "Congenital parvovirus infection", "E": "Congenital varicella infection\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old woman makes an appointment with her gynecologist because she has been having foul smelling vaginal discharge. She says that the symptoms started about a week ago, but she can't think of any particular trigger associated with the onset of symptoms. She says that otherwise she has not experienced any pain or discomfort associated with these discharges. She has never been pregnant and currently has multiple sexual partners with whom she uses protection consistently. She has no other medical history though she says that her family has a history of reproductive system malignancy. Physical exam reveals a normal appearing vulva, and a sample of the vaginal discharge reveals gray fluid. Which of the following characteristics is associated with the most likely cause of this patient's disorder?", "answer": "Oxidase-negative, facultative anaerobe", "options": {"A": "Cervicovaginal friability", "B": "Dimorphic fungus", "C": "Overgrowth of abnormal cervical cells", "D": "Oxidase-negative, facultative anaerobe", "E": "Flagellated, pear-like-shaped trophozoites"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 2-year-old girl is brought to the physician by her mother after she noticed multiple painless, nonpruritic papules on her abdomen. The child attends daycare three times per week, and this past week one child was reported to have similar lesions. Her immunizations are up-to-date. Her brother had chickenpox one month ago. She is at the 50th percentile for height and the 60th percentile for weight. Vital signs are within normal limits. Examination shows several skin-colored, nontender, pearly papules with central umbilication on the abdomen and extremities. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Molluscum contagiosum", "options": {"A": "Insect bites", "B": "Molluscum contagiosum", "C": "Cutaneuous lichen planus", "D": "Verruca vulgaris", "E": "Chickenpox\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old man presents with fever, chills, and malaise which began 5 days ago. He also mentions that the back of his right upper arm feels itchy. He says he works as a forest guide and recently came back from a forest expedition. Upon asking, he reports that the forest where he works is infested with ticks. His temperature is 38.3°C (100.9°F), the pulse is 87/min, the respiratory rate is 15/min, and the blood pressure is 122/90 mm Hg. On physical examination, there is a rash present on the posterior aspect of his upper right arm which is shown in the image. Which of the following medications is the best course of treatment for this patient?", "answer": "Doxycycline", "options": {"A": "Azithromycin", "B": "Clindamycin", "C": "Doxycycline", "D": "Fluconazole", "E": "Trimethoprim-sulfamethoxazole"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old woman is brought to the emergency department by her boyfriend because of a 4-month history of feeling sad. Her boyfriend says that, during this period, she has slept and eaten very little and has been unable to focus at work. She says that she feels “empty inside” and has been hearing voices telling her that she is worthless. She first heard these voices 7 months ago when they started to make fun of her. She does not drink alcohol or use illicit drugs. Physical and neurological examinations show no abnormalities. On mental status examination, her speech is slow and monotonous; she abruptly stops talking in the middle of sentences and does not finish them. She occasionally directs her attention to the ceiling as if she were listening to someone. Which of the following is the most likely diagnosis?", "answer": "Schizoaffective disorder", "options": {"A": "Schizophrenia", "B": "Schizophreniform disorder", "C": "Schizoaffective disorder", "D": "Mood disorder with psychotic features", "E": "Schizotypal personality disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Blood cultures are sent to the laboratory and empiric treatment with intravenous vancomycin is started. Blood cultures grow gram-negative bacilli identified as Cardiobacterium hominis. Which of the following is the most appropriate next step in management?", "answer": "Switch to intravenous ceftriaxone", "options": {"A": "Switch to intravenous ampicillin", "B": "Switch to intravenous ceftriaxone", "C": "Switch to intravenous cefazolin", "D": "Switch to intravenous gentamicin", "E": "Add intravenous rifampin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old man is brought to the emergency department by emergency medical services. The patient was an unrestrained passenger in a head-on collision that occurred 15 minutes ago and is currently unresponsive. His temperature is 99.5°F (37.5°C), blood pressure is 60/33 mmHg, pulse is 180/min, respirations are 17/min, and oxygen saturation is 95% on room air. A FAST exam demonstrates fluid in Morrison’s pouch. Laboratory values are drawn upon presentation to the ED and sent off. The patient is started on IV fluids and an initial trauma survey is started. Twenty minutes later, his blood pressure is 95/65 mmHg, and his pulse is 110/min. The patient is further stabilized and is scheduled for emergency surgery. Which of the following best represents this patient’s most likely initial laboratory values?", "answer": "Hemoglobin: 15 g/dL, Hematocrit: 45%, MCV: 90 µm^3", "options": {"A": "Hemoglobin: 19 g/dL, Hematocrit: 55%, MCV: 95 µm^3", "B": "Hemoglobin: 15 g/dL, Hematocrit: 45%, MCV: 90 µm^3", "C": "Hemoglobin: 11 g/dL, Hematocrit: 33%, MCV: 88 µm^3", "D": "Hemoglobin: 10 g/dL, Hematocrit: 30%, MCV: 110 µm^3", "E": "Hemoglobin: 7 g/dL, Hematocrit: 21%, MCV: 75 µm^3"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old alcoholic male had been taken to the emergency room after he was found unconscious covered in vomitus. After regaining consciousness, he complained of a constant productive cough with foul-smelling sputum for the past few weeks. A chest x-ray(Image A) was taken and the patient was treated accordingly. The patient comes to you today complaining of watery diarrhea. Which best describes the pathogen causing diarrhea?", "answer": "Gram-positive bacilli, motile, spore-forming, obligate anaerobe", "options": {"A": "Gram-positive bacilli, motile, spore-forming, obligate anaerobe", "B": "Gram-negative bacilli, lactose non-fermenter, glucose fermenter, oxidase positive", "C": "Gram-positive bacilli, non-motile spore-forming, aerobe", "D": "Gram-negative bacilli, lactose non-fermenter, oxidase negative, and hydrogen sulfide producer", "E": "Gram-negative bacilli, lactose non-fermenter, oxidase negative, and does not produce hydrogen sulfide"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old African American woman presents to her family physician for a routine examination. Past medical history is positive for amyloidosis and non-rhythm-based cardiac abnormalities secondary to the amyloidosis. Which of the following cardiac parameters would be expected in this patient?", "answer": "Preserved ejection fraction and decreased compliance", "options": {"A": "Preserved ejection fraction and increased compliance", "B": "Preserved ejection fraction and decreased compliance", "C": "Decreased ejection fraction and increased compliance", "D": "Decreased ejection fraction and decreased compliance", "E": "Increased ejection fraction and decreased compliance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old healthy woman presents with lightheadedness, palpitations, and sweating, which started suddenly after she was frightened by her neighbor’s dog. The patient’s blood pressure is 135/80 mm Hg, the heart rate is 150/min, the respiratory rate is 15/min, and the temperature is 36.6℃ (97.9℉). Her ECG is shown in the exhibit. What is the preferred agent for pharmacologic management of this condition?", "answer": "Adenosine", "options": {"A": "Verapamil", "B": "Metoprolol", "C": "Amiodarone", "D": "Adenosine", "E": "Propafenone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old female presents to the emergency room with acute onset of dyspnea and hemoptysis. Her past medical history is unremarkable and she has had no prior surgeries. A ventilation-perfusion scan demonstrates a large perfusion defect that is not matched by a ventilation defect in the left lower lobe. Which of the following would you also expect to find in this patient:", "answer": "Pleuritic chest pain", "options": {"A": "Pleuritic chest pain", "B": "Bradycardia", "C": "Aortic dilation", "D": "Claudication", "E": "Increased inspiratory capacity"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "In patients with chronic obstructive pulmonary disease, stimulation of muscarinic acetylcholine receptors results in an increase in mucus secretion, smooth muscle contraction and bronchoconstriction. The end result is an increase in airway resistance. Which of the following pharmacologic agents interferes directly with this pathway?", "answer": "Ipratropium", "options": {"A": "Epinephrine", "B": "Theophylline", "C": "Ipratropium", "D": "Albuterol", "E": "Metoprolol"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year old primigravid woman at 37 weeks' gestation comes to the emergency department because of frequent contractions for 4 hours. Her pregnancy has been complicated by hyperemesis gravidarum which subsided in the second trimester. The contractions occur every 10–15 minutes and have been increasing in intensity and duration since onset. Her temperature is 37.1°C (98.8°F), pulse is 110/min, and blood pressure is 140/85 mm Hg. Uterine contractions are felt on palpation. Pelvic examination shows clear fluid in the vagina. The cervix is 50% effaced and 3 cm dilated. After 4 hours the cervix is 80% effaced and 6 cm dilated. Pelvic examination is inconclusive for the position of the fetal head. The fetal heart rate is reassuring. Which of the following is the most appropriate next step?", "answer": "Perform ultrasonography", "options": {"A": "Perform ultrasonography", "B": "Perform external cephalic version", "C": "Administer misoprostol", "D": "Administer oxytocin", "E": "Perform Mauriceau-Smellie-Veit maneuver"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man presents with sudden onset palpitations for the past couple of hours. He denies any chest pain. Past medical history is significant for unknown kidney disease. Current medications are amiloride and daily aspirin. His blood pressure is 123/87 mm Hg and pulse is 45/min. Physical examination is unremarkable. An ECG shows tall peaked T waves with sinus bradycardia. Laboratory findings are significant for serum potassium of 6.1 mEq/L. Which of the following therapies may worsen this patient’s condition?\n   ", "answer": "Administering a β-antagonist", "options": {"A": " 50 mL of 50% glucose solution with 10 units of soluble insulin by intravenous infusion", "B": "50 ml of Sodium bicarbonate (8.4%) ", "C": "Stopping amiloride", "D": "Calcium resonium", "E": "Administering a β-antagonist"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-year-old boy is brought by his mother to the emergency room because of a swollen, hot, and tender knee that he sustained after falling on his way home. He has never had a swollen joint before; however, he has had frequent nosebleeds throughout his life. His mother is worried because they live with her parents who are currently on blood thinners. Every morning she puts the blood thinner pill in the boy's grandfather's milk and was concerned that she may have switched it this morning. Family history reveals a number of uncles who have had bleeding disorders; however, the mother does not know the exact disorder suffered by these relatives. A hematologic panel reveals the following findings:\n\nBleeding time: Increased\nProthrombin time: 12 seconds\nPartial thromboplastin time (PTT): 55 seconds\nPTT after factor mixing study: 37 seconds\n\nWhich of the following most likely explains the abnormal partial thromboplastin time in this patient?", "answer": "Mutation in carrying protein", "options": {"A": "Activation of inhibitory factors", "B": "Antibodies to factor VIII", "C": "Inhibition of reductase enzyme", "D": "Mutation in carrying protein", "E": "Mutation in factor VIII"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 6-year-old girl is brought to the physician because of increasing swelling around her eyes for the past 3 days. Her vital signs are within normal limits. Physical examination shows periorbital edema and abdominal distention with shifting dullness. Laboratory studies show a serum albumin of 2 g/dL and a serum cholesterol concentration of 290 mg/dL. Urinalysis shows 4+ proteinuria and fatty casts. Histological examination of a kidney biopsy specimen is most likely to show which of the following findings?", "answer": "Normal glomeruli on light microscopy", "options": {"A": "Granular subepithelial deposits of IgG, IgM, and C3 on immunofluorescence", "B": "Mesangial proliferation on light microscopy", "C": "Deposits of IgG and C3 at the glomerular basement membrane on immunofluoresence", "D": "Subepithelial dense deposits on electron microscopy", "E": "Normal glomeruli on light microscopy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 58-year-old right-handed man is brought to the emergency department after he was found unconscious in his living room by his wife. She reports that he has never had a similar episode before. The patient has hypertension and consumes multiple alcoholic drinks per day. On arrival, he is confused and oriented only to person. He cannot recall what happened. He has difficulty speaking and his words are slurred. He reports a diffuse headache and muscle pain and appears fatigued. His temperature is 37°C (98.6°F), pulse is 85/min, respirations are 14/min, and blood pressure is 135/70 mm Hg. Examination shows a 2-cm bruise on his right shoulder. Strength is 5/5 throughout, except for 1/5 in the left arm. The remainder of the physical examination shows no abnormalities. An ECG shows left ventricular hypertrophy. A CT scan of the head without contrast shows no abnormalities. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Seizure", "options": {"A": "Stroke", "B": "Transient ischemic attack", "C": "Migraine", "D": "Syncope", "E": "Seizure"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old man comes to the physician for a health maintenance examination. He has had generalized fatigue and muscle aches since his previous visit 6 months ago. He has hypertension and gastroesophageal reflux disease. Current medications include amlodipine and omeprazole. His temperature is 37.1°C (98.1°F), pulse is 88/min and blood pressure is 156/102 mm Hg. Physical examination shows no abnormalities. Serum studies show:\nNa+ 143 mEq/L\nK+ 2.3 mEq/L\nCl- 100 mEq/L\nHCO3- 31 mEq/L\nUrea nitrogen 14 mg/dL\nCreatinine 1 mg/dL\nHis blood pressure medication is discontinued. One week later his plasma aldosterone concentration is 35 ng/dL (N=3.6 - 24.0 ng/dL) and plasma renin activity is 0.4 ng/mL/h (N=0.3 to 4.2 ng/mL/h). An oral sodium loading test over 3 days fails to reduce aldosterone. A contrast-enhanced CT scan of the abdomen and pelvis shows a 3-cm, homogenous, right-sided adrenal mass with rapid contrast washout. He is counseled about his treatment options and chooses to pursue surgery. Which of the following is the most appropriate next step in management?\"", "answer": "Adrenal vein sampling", "options": {"A": "Spironolactone therapy", "B": "Right adrenalectomy", "C": "Fludrocortisone suppression test", "D": "Adrenal vein sampling", "E": "Bilateral adrenalectomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An otherwise healthy, exclusively breastfed 4-day-old neonate is brought to the physician because of yellowing of his skin and eyes. His urine has been clear and stools have been normal. He was born at term by vacuum-assisted delivery and weighed 4000 g (8 lb 8 oz). Pregnancy was complicated by gestational diabetes mellitus. His older sibling had jaundice in the neonatal period. Vital signs are within normal limits. He appears alert and comfortable. Physical examination shows jaundice of the skin and sclerae. The liver is palpated 1 cm below the right costal margin. Laboratory studies show:\nHemoglobin 17 g/dl\nReticulocyte count 0.5 %\nTotal bilirubin 21.2 mg/dl\nDirect bilirubin 2 mg/dl\nIndirect bilirubin 19.1 mg/dl\nCoombs test Negative\nWhich of the following is the most appropriate next step in management?\"", "answer": "Phototherapy", "options": {"A": "Intravenous immunoglobulin", "B": "Increase frequency of breast feeds", "C": "Replace breast feeding with formula feeds", "D": "MRI of the brain", "E": "Phototherapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 34-year-old woman is recovering in the post-operative unit following a laparoscopic procedure for chronic endometriosis. She had initially presented with complaints of painful menstrual cramps that kept her bedridden most of the day. She also mentioned to her gynecologist that she had been diagnosed with endometriosis 4 years ago, and she could not find a medication or alternative therapeutic measure that helped. Her medical history was significant for surgery she had 6 years ago to remove tumors she had above her kidneys, after which she was prescribed hydrocortisone. An hour after the laparoscopic procedure, she calls the nurse because she is having difficulty breathing. The nurse records her vital signs include: blood pressure 85/55 mm Hg, respirations 20/min, and pulse 115/min. The patient suddenly loses consciousness. Intravenous fluids are started immediately. She gains consciousness, but her blood pressure is unchanged. Which of the following is the most likely cause of the hypotension?", "answer": "Improper supplementation of steroids", "options": {"A": "Infection involving the suture line", "B": "Loss of fluids during the procedure", "C": "Bleeding profusely through the surgical site", "D": "Improper supplementation of steroids", "E": "High doses of anesthetic drugs"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old female presents to the emergency department with right lower abdominal pain that began suddenly one hour ago. She is writhing in discomfort and has vomited twice since arrival. She has no chronic medical conditions, but states she has had chlamydia two or three times in the past. Her abdomen is firm, and she is guarding. Pelvic exam reveals blood pooling in the vagina and right adnexal tenderness. Her last menstrual period was 7 weeks ago. A pregnancy test is positive.\n\nWhich of the following is an appropriate next step in diagnosis?", "answer": "Transvaginal ultrasound", "options": {"A": "Transabdominal ultrasound.", "B": "Dilation and curettage", "C": "Transvaginal ultrasound", "D": "Methotrexate and discharge with strict follow-up instructions.", "E": "Exploratory laparotomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 47-year-old woman comes to the physician because of a 1-month history of progressive weakness. She has had increased difficulty climbing stairs and standing from a seated position. She takes no medications. Neurologic examination shows weakness of the proximal muscles. Skin examination shows diffuse erythema of the upper back, posterior neck, and shoulders. A photograph of the patient's eye is shown. Antibodies against which of the following are most likely to be present in this patient?", "answer": "Mi-2 protein", "options": {"A": "Centromeres", "B": "La protein", "C": "Scl-70 protein", "D": "Mi-2 protein", "E": "Histones"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 78-year-old man presents to the emergency department because of confusion that started 2 hours ago. The patient’s daughter says that he has had blurred vision for several days. His right leg became weak 10 days ago, and he couldn’t walk for a few days before recovering. He was diagnosed with monoclonal gammopathy of undetermined significance 2 years ago. His temperature is 36.2°C (97.2°F), pulse is 75/min, respirations are 13/min, and blood pressure is 125/70 mm Hg. He also has gingival bleeding. Cervical lymphadenopathy is palpated on physical exam. Both the liver and spleen are palpated 5 cm below the costal margins. The serum protein electrophoresis with immunofixation is shown. Urine electrophoresis shows no abnormalities. A skeletal survey shows no abnormalities. Which of the following best explains these findings?", "answer": "Waldenstrom’s macroglobulinemia", "options": {"A": "Chronic lymphocytic leukemia", "B": "Diffuse large B-cell lymphoma", "C": "Monoclonal gammopathy of undetermined significance", "D": "Multiple myeloma", "E": "Waldenstrom’s macroglobulinemia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 17-year-old girl is being evaluated for primary amenorrhea. A pelvic ultrasound shows no uterus, fallopian tubes, or ovaries, despite having normal external sexual organs. On physical examination, there is no axillary or pubic hair, and breast development is normal. The laboratory tests show evidence of increased serum testosterone with normal conversion to dihydrotestosterone (DHT) and increased luteinizing hormone (LH). What is the karyotype of this patient?", "answer": "46, XY", "options": {"A": "46, XX", "B": "47, XXX", "C": "47, XXY", "D": "46, XY", "E": "45, X0"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 41-year-old male with a history of pneumocystis jiroveci pneumonia is found to have multiple ring-enhancing lesions on brain CT. Which of the following is most likely responsible for this patient's abnormal scan?", "answer": "Protozoa", "options": {"A": "Neoplasm", "B": "Bacteria", "C": "Virus", "D": "Prion", "E": "Protozoa"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 13-year-old boy presents to the emergency department with severe abdominal pain. His parents state that he has been complaining of abdominal pain that became increasingly severe this evening. They also state he has been eating much more lately yet still has been losing weight. The patient's past medical history is unremarkable and he is not currently on any medications. His temperature is 99.5°F (37.5°C), blood pressure is 90/58 mmHg, pulse is 150/min, respirations are 24/min, and oxygen saturation is 98% on room air. Physical exam is notable for diffuse abdominal tenderness and tachycardia. Laboratory values are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nBUN: 20 mg/dL\nGlucose: 599 mg/dL\nCreatinine: 1.1 mg/dL\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following laboratory changes best reflects this patient's physiology as compared to his baseline?", "answer": "C", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old man is bitten by a cottonmouth viper and is successfully treated with sheep hyperimmune Fab antivenom. Three days later, the patient develops an abdominal itchy rash and re-presents to the emergency department for medical care. His medical history is significant for gout, hypertension, hypercholesterolemia, diabetes mellitus type II, and multiple basal cell carcinomas on his face and neck. He currently smokes 1 pack of cigarettes per day, drinks a 6-pack of beer per day, and denies any current illicit drug use. His vital signs include: temperature 40.0°C (104.0°F), blood pressure 126/74 mm Hg, heart rate 111/min, and respiratory rate 23/min. On physical examination, his gait is limited by diffuse arthralgias, lung sounds are clear bilaterally, and he has normal heart sounds. The patient has a pruritic periumbilical serpiginous macular rash that has spread to involve the back, upper trunk, and extremities. Of the following options, which is the next best step in patient management?", "answer": "Glucocorticoid taper with antihistamines", "options": {"A": "Dialysis", "B": "Glucocorticoid taper with antihistamines", "C": "Antihistamines", "D": "NSAIDs", "E": "Plasmapheresis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 47-year-old man presents to the clinic for an evaluation of intense itching of his right thigh region for the past few days. He states some ‘red bumps’ just began to form. The patient mentions that he was recently at a business conference in Miami. He has a past medical history of hypertension, diabetes type 2, and hyperlipidemia. He takes enalapril, metformin, and atorvastatin. He does not smoke or drink. His vitals are within normal limits today. On physical examination, a linear line with 3 red papules is present along the medial aspect of his right thigh. Additionally, there are small rows of bumps on his left leg and right forearm. Excoriations are also apparent in the same region. Which of the following is the most likely diagnosis?", "answer": "Bed bug bite", "options": {"A": "Scabies", "B": "Cutaneous larva migrans", "C": "Bed bug bite", "D": "Spider bite", "E": "Flea bite"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old woman presents to her primary care doctor with a lesion on her labia. She first noticed the lesion 2 days ago. It is not painful. She denies vaginal discharge or dysuria. She has no past medical history and takes no medications. She has had 4 sexual partners in the past 8 months and uses the pull-out method as contraception. She drinks 12-16 alcoholic beverages per week and is a law student. Her temperature is 97.8°F (36.6°C), blood pressure is 121/81 mmHg, pulse is 70/min, and respirations are 16/min. On exam, she has an indurated non-tender ulcer on the left labia majora. There is no appreciable inguinal lymphadenopathy. Multiple tests are ordered and pending. This patient's condition is most likely caused by a pathogen with which of the following characteristics on histologic imaging?", "answer": "Motile and helical-shaped bacteria", "options": {"A": "Gram-negative coccobacillus with a \"school of fish\" appearance", "B": "Gram-negative diplococci", "C": "Motile and helical-shaped bacteria", "D": "Rod-shaped organisms in phagocyte cytoplasm", "E": "Vaginal epithelial cells covered with bacteria"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old man presents with fever, headache, and vomiting. He says that symptoms onset acutely 2 days ago and have not improved. He also reports associated weakness and chills. Past medical history is significant for occasional heartburn. His temperature is 39.4°C (103.0°F), the pulse rate is 124/min, the blood pressure is 130/84 mm Hg, and the respiratory rate is 22/min. On physical examination, there is significant nuchal rigidity. No signs of raised intracranial pressure are present. A lumbar puncture is performed and cerebrospinal fluid (CSF) analysis shows lymphocyte-dominant pleocytosis with increased CSF protein levels. Bacteriological culture of the CSF reveals the growth of Listeria monocytogenes. Which of the following antibiotics is the best choice for the treatment of this patient?", "answer": "Ampicillin", "options": {"A": "Ampicillin", "B": "Ceftriaxone", "C": "Chloramphenicol", "D": "Ciprofloxacin", "E": "Vancomycin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 15-year-old girl presents to her primary care physician, accompanied by her mother, for 4 days of abdominal pain. She describes the pain as diffuse, dull, and constant. She also endorses constipation over this time. The patient's mother says the patient has become increasingly self-conscious of her appearance since starting high school this year and has increasingly isolated herself to her room, rarely spending time with or eating meals with the rest of the family. Her temperature is 98.0°F (36.7°C), blood pressure is 100/70 mmHg, pulse is 55/min, and respirations are 19/min. Body mass index (BMI) is at the 4th percentile for age and gender. Physical exam reveals dental caries, mild abdominal distension, and diffuse, fine body hair. Basic labs are most likely to reveal which of the following?", "answer": "Hypokalemia", "options": {"A": "Hypocalcemia", "B": "Hypokalemia", "C": "Hypercalcemia", "D": "Hyperkalemia", "E": "Hyperphosphatemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 66-year-old white man comes to the physician because of a 10-day history of fatigue and lower leg swelling. Over the past 6 months, he has had a 3.6-kg (8-lb) weight loss. He has chronic bronchitis and uses an albuterol inhaler as needed. He has smoked one pack of cigarettes daily for 44 years and drinks one alcoholic beverage daily. His temperature is 37°C (98.6°F), pulse is 88/min, and blood pressure is 120/75 mm Hg. He appears thin. Examination shows 2+ pretibial edema bilaterally. Cardiopulmonary examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11.2 g/dL\nLeukocyte count 8500/mm3\nPlatelet count 130,000/mm3\nSerum\nUrea nitrogen 23 mg/dL\nGlucose 77 mg/dL\nCreatinine 1.6 mg/dL\nAlbumin 1.8 mg/dL\nTotal cholesterol 475 mg/dL\nUrine\nBlood negative\nGlucose negative\nProtein 4+\nWBC 0–1/hpf\nFatty casts numerous\nAn x-ray of the chest shows a right upper lobe density. A CT scan of the chest shows a 2.5 x 3.5 x 2-cm right upper lobe mass. Which of the following is the most likely diagnosis?\"", "answer": "Membranous nephropathy", "options": {"A": "Focal segmental glomerulosclerosis", "B": "Granulomatosis with polyangiitis", "C": "Membranous nephropathy", "D": "Rapidly progressive glomerulonephritis", "E": "Thin basement membrane disease\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 80-year-old male with known metastatic prostate cancer presents to your office with vague complaints of \"achy bones.\" Strangely, he refers to you using the name of another physician. On physical exam, he is afebrile, but mildly tachycardic at 100 beats/min. Mucous membranes are dry. Cardiac exam shows regular rhythm and no murmurs. The patient has diffuse, nonfocal abdominal pain. He cannot articulate the correct date. You check the patient's serum calcium level, which is found to be 15.3 mg/dL. What is the best next step in management?", "answer": "Intravenous normal saline", "options": {"A": "Pamidronate", "B": "Intravenous normal saline", "C": "Calcitonin", "D": "Furosemide", "E": "Hemodialysis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A new drug is designed to treat asthma by inhibiting bronchoconstriction. Experimental assays show that treated animals had markedly reduced acetylcholine binding to muscarinic receptors relative to untreated controls. The drug is most similar to which of the following:", "answer": "Ipratropium", "options": {"A": "Theophylline", "B": "Cromolyn", "C": "Zafirlukast", "D": "Prednisone", "E": "Ipratropium"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old man presents to the outpatient clinic with a complaint of right-sided jaw pain. The onset of pain was approx. 1 month ago and he is experiencing symptoms 2–3 times a day. Each episode of pain lasts for about 30 seconds. He describes the pain as severe (9 out of 10) with an electric and sharp quality. He denies having tear production or conjunctival injection on the affected side during attacks. What is the mechanism of action for the drug that will best treat this patient’s condition?", "answer": "Prevention of Na+ influx", "options": {"A": "Prevention of Na+ influx", "B": "Decrease the excitatory effects of glutamic acid", "C": "Increase the frequency of Cl- channel opening", "D": "Increase the time of Cl- channel opening", "E": "Decrease in the Ca2+ influx"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old African-American male presents to his family physician after noticing red-tinged urine the week before, when he was suffering from a cold. The patient states that he had experienced that before. His father is with him and says that this happens to him on occasion as well. What is the most likely diagnosis for this patient?", "answer": "Sickle cell trait", "options": {"A": "Acute cystitis", "B": "Acute interstitial nephritis", "C": "Sickle cell trait", "D": "Acute glomerulonephritis", "E": "Hemophilia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-year-old boy is brought to the physician by his mother for a well-child examination. At the visit, the mother says that she is worried about the child's vision because of an “eye condition that runs in the family.” She says that the child is doing well in all activities at his preschool, except one in which he is required to sort different colored balls into baskets of a corresponding color. A pedigree chart of the family, with the patient identified by a red arrow, is shown. The most likely cause of these changes in the patient's vision involves which of the following modes of inheritance?", "answer": "X-linked recessive", "options": {"A": "Mitochondrial inheritance", "B": "Autosomal recessive", "C": "Y-linked dominant", "D": "X-linked recessive", "E": "Autosomal dominant"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 71-year-old African American man with a history of prostatic adenocarcinoma presents to his oncologist with low back pain. He was diagnosed with non-resectable prostatic adenocarcinoma 4 years ago. He has undergone radiation therapy and chemotherapy. Over the past 3 months, he has developed constant mild non-radiating low back pain that occasionally wakes him up from sleep. He denies any recent falls or trauma. His past medical history is notable for hypertension, diabetes mellitus, coronary artery disease, and gout. He also has a history of thyroid cancer and underwent thyroidectomy 5 years ago. He takes lisinopril, metoprolol, aspirin, metformin, and allopurinol. He has a 40-pack-year smoking history and drinks alcohol socially. His temperature is 99.2°F (37.3°C), blood pressure is 150/85 mmHg, pulse is 84/min, and respirations are 18/min. On exam, he is well-appearing and in no acute distress. He is mildly tender to palpation along the lumbar vertebral spinous processes. A computerized tomography (CT) scan of the lumbar spine demonstrates a blastic and sclerotic lesion in the L5 vertebral body. Which of the following findings would most likely be seen on a serum study of this patient?", "answer": "Normal calcium, normal phosphate, increased alkaline phosphatase, and normal parathyroid hormone", "options": {"A": "Decreased calcium, decreased phosphate, increased alkaline phosphatase, and increased parathyroid hormone", "B": "Decreased calcium, increased phosphate, increased alkaline phosphatase, and increased parathyroid hormone", "C": "Increased calcium, decreased phosphate, increased alkaline phosphatase, and increased parathyroid hormone", "D": "Normal calcium, normal phosphate, increased alkaline phosphatase, and normal parathyroid hormone", "E": "Normal calcium, normal phosphate, normal alkaline phosphatase, and normal parathyroid hormone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 44-year-old Caucasian male presents with a fever, recent weight loss, and a cough productive of bloody sputum. A chest X-ray and CT scan were performed, revealing cavities near the apex of his lungs. The patient is started on rifampin, isoniazid, ethambutol and pyrazinamide. Formation of the cavities in the patient's lungs is mainly mediated by:", "answer": "TH1 cells", "options": {"A": "TH1 cells", "B": "Toxin secretion by the bacterium", "C": "B-cells", "D": "NK cells", "E": "Apoptosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old man presents to his primary care physician with a 6-month history of increasing joint pain and stiffness. He says that the pain is primarily located in his knees and occurs in sharp bursts that are accompanied by redness and warmth. His past medical history is significant for diabetes though he is not currently taking any medications. He also suffers from occasional diarrhea with fatty stools. Physical exam reveals mild swelling and redness in his knees bilaterally. Furthermore, he is found to be very tan despite the fact that he says he stays out of the sun. He notes that he has always been significantly more tan than anyone else in his family. This patient is most likely predisposed to which of the following diseases?", "answer": "Hepatocellular carcinoma", "options": {"A": "Basal cell carcinoma", "B": "Hepatocellular carcinoma", "C": "Osteosarcoma", "D": "Pancreatic adenocarcinoma", "E": "Squamous cell skin carcinoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old chronic smoker known to have chronic bronchitis for the last 20 years presents to his physician for a scheduled follow-up visit. He mentions that over the last month he has been having difficulty breathing, especially after climbing stairs. He also says that he has had similar episodes in the past, which were relieved with the use of inhaled bronchodilators, but recently the breathlessness has ceased to respond to them. He also mentions frequent pain in the right upper quadrant of the abdomen. On physical examination, his temperature is 37°C (98.6°F), the pulse is 96/min, the blood pressure is 124/82 mm Hg, and the respirations are 26/min. Auscultation of the chest reveals wheezing bilaterally and a loud pulmonic component of the second heart sound. Two-dimensional echocardiography shows a dilated right ventricle with increased wall thickness. Right heart catheterization is performed, which indicates a pulmonary artery pressure of 30 mm Hg and a pulmonary capillary wedge pressure of 13 mm Hg. There is a significant drop in pulmonary artery pressure after the administration of inhaled nitric oxide. In addition to continued appropriate management of chronic bronchitis, which of the following medications is most likely to improve symptoms in the patient?", "answer": "Diltiazem", "options": {"A": "Captopril", "B": "Diltiazem", "C": "Hydralazine", "D": "Isosorbide mononitrate", "E": "Losartan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 70-year-old man presents to the clinic with right-sided chest pain and difficulty breathing for the past 10 days. When it began, the pain was mild, but as time went on, it increased to a level at which the man found it difficult to breathe. Two years ago, he was diagnosed with clear cell carcinoma of the kidney. Vital signs include: pulse rate is 72/min, blood pressure is 122/80 mm Hg, respiratory rate is 16/min, and temperature is 37.0°C (98.6°F). On physical examination, the trachea appears to have deviated to the left, respiratory movements are diminished, there is decreased resonance on percussion, and there is an absence of breath sounds over the right hemithorax. Which of the following is the most likely clinical diagnosis in this patient?", "answer": "Pleural effusion", "options": {"A": "Pneumonia", "B": "Atelectasis", "C": "Pneumothorax", "D": "Pulmonary embolism", "E": "Pleural effusion"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 1-month-old boy is brought in by his mother for episodes of “not breathing.” She reports noticing that the patient will occasionally stop breathing while he’s sleeping, and that these episodes have been occurring more frequently. The patient was born at 32 weeks due to placental insufficiency. He was in the neonatal intensive care unit for 1 day to be placed on a respirator. During prenatal testing, it was revealed that the mother was not immune to rubella, but she otherwise had an uncomplicated pregnancy. She has no medical conditions and took only prenatal vitamins. The patient has a 3-year-old sister who is healthy. His father has a “heart condition.” The patient’s temperature is 98°F (36.7°C), blood pressure is 91/55 mmHg, pulse is 207/min, and respirations are 50/min with an oxygen saturation of 97% on room air. Physical examination is notable for pale conjunctiva. Labs are obtained, as shown below:\n\nLeukocyte count: 10,000/mm^3 with normal differential\nHemoglobin: 8.2 g/dL\nHematocrit: 28%\nMean corpuscular volume (MCV): 100 um^3\nPlatelet count: 300,000/mm^3\nReticulocyte count: 0.8% (normal range: 2-6%)\nLactate dehydrogenase: 120 U/L (normal range: 100-250 U/L)\n\nA peripheral smear reveals normocytic and normochromic red blood cells. Which of the following is a mechanism for the patient’s most likely diagnosis?", "answer": "Impaired erythropoietin production", "options": {"A": "Congenital infection", "B": "Hemoglobinopathy", "C": "Impaired erythropoietin production", "D": "Minor blood group incompatibility", "E": "Red blood cell membrane defect"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 63-year-old man presents to his family physician with limited movement in his left shoulder that has progressed gradually over the past 6 years. He previously had pain when moving his shoulder, but the pain subsided a year ago and now he experiences the inability to fully flex, abduct, and rotate his left arm. He had an injury to his left shoulder 10 years ago when he fell onto his arms and ‘stretched ligaments’. He did not seek medical care and managed the pain with NSAIDs and rest. He has diabetes mellitus that is well controlled with Metformin. His blood pressure is 130/80 mm Hg, the heart rate is 81/min, the respiratory rate is 15/min, and the temperature is 36.6°C (97.9°F). Physical examination reveals limitations of both active and passive abduction and external rotation in the left arm. The range of motion in the right glenohumeral joint is normal. The muscles of the left shoulder look less bulky than those of the right shoulder. There is no change in shoulder muscle power bilaterally. The reflexes and sensation on the upper extremities are normal. Which of the following is the next best step for this patient?", "answer": "Physical therapy", "options": {"A": "No interventions are required at this stage", "B": "NSAID prescription for 1–2 weeks", "C": "Physical therapy", "D": "Corticosteroid injections", "E": "Arthroscopic capsular release"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old man comes to the emergency department because of sharp chest pain for 3 days. The pain is retrosternal, 8 out of 10 in intensity, increases with respiration, and decreases while sitting upright and leaning forward. He has nausea and myalgia. He has not had fever or a cough. He has asthma and was treated for bronchitis 6 months ago with azithromycin. His mother has hypertension. He uses an over-the-counter inhaler. His temperature is 37.3°C (99.1°F), pulse is 110/min, and blood pressure is 130/84 mm Hg. Breath sounds are normal. Cardiac examination shows a high-pitched grating sound between S1 and S2. The remainder of the examination shows no abnormalities. Serum studies show:\nUrea nitrogen 16 mg/dl\nGlucose 103 mg/dL\nCreatinine 0.7 mg/dL\nTroponin I 0.230 ng/mL (N < 0.1 ng/mL)\nAn ECG shows diffuse ST elevations in all leads. The patient is at increased risk for which of the following conditions?\"", "answer": "Cardiac tamponade", "options": {"A": "Papillary muscle rupture", "B": "Pulmonary infarction", "C": "Mediastinitis", "D": "Cardiac tamponade", "E": "Ventricular aneurysm"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old man comes to the physician because of a 2-day history of an itchy rash. He has no history of skin problems. He had an upper respiratory infection 4 days ago that resolved with acetaminophen and over-the-counter cold medication. He has type I diabetes mellitus well-controlled with insulin. He was also diagnosed with hypertension 3 weeks ago and treatment with captopril was initiated. His temperature is 36.8°C (98.2°F), pulse is 68/min, respirations are 18/min, and blood pressure is 120/85 mm Hg. Examination shows rashes at the waistline, trunk, and over the forearms. A photograph of the right forearm is shown. The rashes are nontender and blanch on pressure. There is no lymphadenopathy or hepatosplenomegaly. Which of the following is the most likely explanation for this patient's skin findings?", "answer": "Cutaneous mast cell activation", "options": {"A": "Epidermal keratinocyte hyperproliferation", "B": "Cutaneous Trichophyton rubrum infection", "C": "Cutaneous cytotoxic reaction", "D": "Impaired bradykinin degradation", "E": "Cutaneous mast cell activation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old man comes to the clinic complaining of back pain for the past 1 month. The pain is described as a dull ache that intensifies intermittently to an 8/10 in severity about 1-2 times a day. It intensified about 2 weeks ago following a fall during a ski trip. He reports that he noticed some pain at his buttocks and lower back following the fall but he wasn’t bothered by it. Hot packs and Tylenol seem to alleviate the pain somewhat. He denies lower extremity weakness, loss of sensation, fever, incontinence, or prior cancers; however, he reveals that his cousin was recently diagnosed with prostate cancer. Physical examination demonstrates normal range of motion and diffuse tenderness at the L4/L5 region with no point tenderness or vertebral step-offs. What is the next best step in the management of this patient?", "answer": "Exercise therapy with NSAIDs/acetaminophen", "options": {"A": "Back bracing", "B": "Best rest with return to activity in 1 week", "C": "Exercise therapy with NSAIDs/acetaminophen", "D": "Morphine as needed", "E": "Radiograph of lumbar spine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 75-year-old man is brought to the emergency department 20 minutes after an episode of being unconscious. He was playing with his 3-year-old granddaughter when he suddenly fell down and was unresponsive for 1-minute. He responded normally after regaining consciousness. He has had episodes of mild chest pain and abdominal discomfort for the past 2 months, especially while working on his car. He has hypertension treated with hydrochlorothiazide. He appears alert. His temperature is 37.1°C (98.8°F), pulse is 89/min and regular, and blood pressure is 110/88 mm Hg. Examination shows a 3/6 late systolic murmur at the right sternal border that radiates to the carotids. There is no swelling or erythema of the lower extremities. Neurologic examination shows no focal findings. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Calcification of the aortic valve", "options": {"A": "Rupture of the chordae tendineae", "B": "Fibrosis of the sinus node", "C": "Asymmetric septal hypertrophy", "D": "Calcification of the aortic valve", "E": "Embolus in the pulmonary artery"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old male presents to general medical clinic reporting sleeping difficulties. He states that he has daytime sleepiness, having fallen asleep several times while driving his car recently. He sometimes experiences very vivid dreams just before awakening. You ask the patient's wife if she has witnessed any episodes where her husband lost all muscle tone and fell to the ground, and she confirms that he has not had this symptom. The patient notes that this condition runs in his family, and he desperately asks for treatment. You begin him on a first-line medication for this illness, which works by which mechanism of action?", "answer": "Enhances release of norepinephrine vesicles", "options": {"A": "Agonist at the GABA receptor", "B": "Agonist at the mu opioid receptor", "C": "Blockade of 5HT reuptake", "D": "Enhances release of norepinephrine vesicles", "E": "Alpha-2 receptor antagonist"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old woman is brought to the emergency department by ambulance after being found unconscious in her bedroom by her roommate. The roommate says the patient has type 1 diabetes and takes her insulin regularly. Her pulse is 110/min, the respiratory rate is 24/min, the temperature is 36.6°C (97.9°F), and the blood pressure is 95/65 mm Hg. She is breathing heavily and gives irrelevant responses to questions. Her skin and mucous membranes appear dry. Her breath has a fruity smell to it. Tendon reflexes are slightly delayed. The laboratory findings include:\nFinger-stick glucose  530 mg/dL\n    Arterial blood gas analysis \npH 7.1\npO2 94 mm Hg\npCO2 32 mm Hg\nHCO3 17 mEq/L\n    Serum  \nSodium 136 mEq/L\nPotassium 3.2 mEq/L\nChloride 136 mEq/L\n    Blood urea nitrogen  20 mg/dL\nSerum creatinine 1.2 mg/dL\n    Urine examination \nGlucose positive\nKetones positive\nLeucocytes negative\nNitrite negative\nRBC negative\nCasts negative\nWhich of the following abnormalities accounts for her sweet smelling breath?", "answer": "Excessive mobilization of fatty acids", "options": {"A": "Diminished glucose metabolism", "B": "Excessive mobilization of fatty acids", "C": "Extrahepatic ketone production", "D": "Fermentation of excess blood sugars", "E": "Inhibition of HMG-CoA synthase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 75-year-old man presents to the physician with progressive difficulty reading over the past year. Currently, he avoids driving as he has trouble reading road signs. He has no history of a serious illness and takes no medications. The fundoscopic examination shows localized retinal elevation and drusen. A description of the patient’s visual on the Amsler grid is shown. Fluorescein angiography shows early hyperfluorescence. Which of the following is the most likely diagnosis in this patient?", "answer": "Macular degeneration", "options": {"A": "Central retinal artery occlusion", "B": "Choroidal melanoma", "C": "Macular degeneration", "D": "Open-angle glaucoma", "E": "Retinal detachment"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 44-year-old woman comes to her primary care physician with complaints of irritation and a gritty sensation in her eyes for the past few months. She denies any discharge from her eyes. She has no significant past medical or surgical history. She takes multivitamins occasionally but denies use of any other medication. On further questioning, she expresses her concerns about frequent dental caries for the past 2 years. On examination, her temperature is 37.1°C (98.8°F), blood pressure is 110/80 mm Hg, pulse rate is 74/min, and respiratory rate is 16/min. Which of the following is the most likely cause of her symptoms?", "answer": "Sjögren's syndrome", "options": {"A": "Systemic lupus erythematosus (SLE)", "B": "Sjögren's syndrome", "C": "Rheumatoid arthritis", "D": "Fibromyalgia", "E": "Scleroderma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "The medical student on the pediatric cardiology team is examining a 9-year-old girl who was referred by her primary care physician for unexplained hypertension. She is accompanied by her mother who reveals that the child is generally well but has been significantly less active than her peers for the past year. On exam, the medical student notes a thin girl in no apparent distress appearing slightly younger than stated age. Vital signs reveal a BP is 160/80, HR 80, RR 16. Physical exam is notable only for a clicking sound is noted around the time of systole but otherwise the cardiac exam is normal. Pedal pulses could not be palpated. Which of the following physical exam findings was most likely missed by both the medical student and primary care physician?", "answer": "Webbed neck", "options": {"A": "Cleft palate", "B": "Prominent occiput", "C": "Long philtrum", "D": "Webbed neck", "E": "Single palmar crease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old woman comes to the emergency department complaining of abdominal pain for the past day. The pain is situated in the right upper quadrant, colicky, 8/10, and radiates to the tip of the right shoulder with no aggravating or relieving factors. The pain is associated with nausea but no vomiting. She tried to take over-the-counter antacids which relieved her pain to a certain extent, but not entirely. She does not smoke cigarettes or drink alcohol. She has no past medical illness. Her father died of pancreatic cancer at the age of 75, and her mother has diabetes controlled with medications. Temperature is 38°C (100.4°F), blood pressure is 125/89 mm Hg, pulse is 104/min, respiratory rate is 20/min, and BMI is 29 kg/m2. On abdominal examination, her abdomen is tender to shallow and deep palpation of the right upper quadrant.\nLaboratory test\nComplete blood count\nHemoglobin 13 g/dL\nWBC 15,500/mm3\nPlatelets 145,000/mm3\nBasic metabolic panel\nSerum Na+   137 mEq/L\nSerum K+ 3.6 mEq/L\nSerum Cl-   95 mEq/L\nSerum HCO3- 25 mEq/L\nBUN   10 mg/dL\nSerum creatinine        0.8 mg/dL\nLiver function test\nTotal bilirubin   1.3 mg/dL\nAST   52 U/L\nALT 60 U/L\nUltrasonography of the abdomen shows normal findings. What is the best next step in management of this patient?", "answer": "Cholescintigraphy", "options": {"A": "Emergency cholecystectomy", "B": "Percutaneous cholecystostomy", "C": "Cholescintigraphy", "D": "CT scan", "E": "Reassurance and close follow up"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old girl is brought to the physician because of a 3-week history of generalized fatigue and easy bruising. During the past week, she has also had fever and severe leg pain that wakes her up at night. Her temperature is 38.3°C (100.9°F), pulse is 120/min, and respirations are 30/min. Examination shows cervical and axillary lymphadenopathy. The abdomen is soft and nontender; the liver is palpated 3 cm below the right costal margin, and the spleen is palpated 2 cm below the left costal margin. Laboratory studies show:\nHemoglobin 10.1 g/dL\nLeukocyte count 63,000/mm3\nPlatelet count 27,000/mm3\nA bone marrow aspirate predominantly shows immature cells that stain positive for CD10, CD19, and TdT. Which of the following is the most likely diagnosis?\"", "answer": "Acute lymphoblastic leukemia", "options": {"A": "Hodgkin lymphoma", "B": "Hairy cell leukemia", "C": "Aplastic anemia", "D": "Acute myeloid leukemia", "E": "Acute lymphoblastic leukemia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old woman comes to the physician because of a 2-day history of a burning sensation when urinating and increased urinary frequency. She is concerned about having contracted a sexually transmitted disease. Physical examination shows suprapubic tenderness. Urinalysis shows a negative nitrite test and positive leukocyte esterases. Urine culture grows organisms that show resistance to novobiocin on susceptibility testing. Which of the following is the most likely causal organism of this patient's symptoms?", "answer": "Staphylococcus saprophyticus", "options": {"A": "Staphylococcus epidermidis", "B": "Pseudomonas aeruginosa", "C": "Klebsiella pneumoniae", "D": "Proteus mirabilis", "E": "Staphylococcus saprophyticus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2-day-old male infant is brought to the emergency department by ambulance after his parents noticed that he was convulsing and unresponsive. He was born at home and appeared well initially; however, within 24 hours he became increasingly irritable and lethargic. Furthermore, he stopped feeding and began to experience worsening tachypnea. This continued for about 6 hours, at which point his parents noticed the convulsions and called for an ambulance. Laboratories are obtained with the following results:\n\nOrotic acid: 9.2 mmol/mol creatinine (normal: 1.4-5.3 mmol/mol creatinine)\nAmmonia: 135 µmol/L (normal: < 50 µmol/L)\nCitrulline: 2 µmol/L (normal: 10-45 µmol/L)\n\nWhich of the following treatments would most likely be beneficial to this patient?", "answer": "Benzoate administration", "options": {"A": "Aspartame avoidance", "B": "Benzoate administration", "C": "Fructose avoidance", "D": "Galactose avoidance", "E": "Uridine administration"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old man presents to his physician with a 3-year history of gradually worsening tics and difficulty walking. He was last seen by the physician 5 years ago for anxiety, and he has been buying anti-anxiety medications from an internet website without a prescription as he cannot afford to pay for doctor’s visits. Now, the patient notes that his anxiety is somewhat controlled, but motor difficulties are making it difficult for him to work and socialize. Family history is unobtainable as his parents died in an accident when he was an infant. He grew up in foster care and was always a bright child. An MRI of the brain is ordered; it shows prominent atrophy of the caudate nucleus. Repeats of which of the following trinucleotides are most likely responsible for this patient’s disorder?", "answer": "CAG", "options": {"A": "CCG", "B": "CGG", "C": "GAA", "D": "CAG", "E": "CTG"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man who recently emigrated from Somalia comes to the physician because of a 4-week history of fever, cough, and chest pain. He has had a 5-kg (11-lb) weight loss over the last 3 months despite no changes in appetite. His temperature is 38.1°C (100.6°F). Physical examination shows enlarged cervical lymph nodes. The lungs are clear to auscultation. The results of an interferon-γ release assay are positive. An x-ray of the chest shows bilateral mediastinal lymphadenopathy. A transbronchial needle aspiration biopsy of a mediastinal lymph node is performed; a photomicrograph of the specimen is shown. The structure indicated by the arrow is most likely comprised of which of the following types of cells?", "answer": "Macrophages", "options": {"A": "Macrophages", "B": "Neutrophils", "C": "Fibroblasts", "D": "Natural killer cells", "E": "B cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 1-year-old immigrant girl presents to her pediatrician for a routine well-child check. She has not received any recommended vaccines since birth. She attends daycare and remains healthy despite her daily association with several other children for the past 3 months at a home daycare facility. Which of the following phenomena explains why she has not contracted any vaccine-preventable diseases such as measles, diphtheria, or pertussis?", "answer": "Herd immunity", "options": {"A": "Herd immunity", "B": "Genetic drift", "C": "Genetic shift", "D": "Tolerance", "E": "Immune evasion"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A pharmaceutical company has modified one of its existing antibiotics to have an improved toxicity profile. The new antibiotic blocks protein synthesis by first entering the cell and then binding to active ribosomes. The antibiotic mimics the structure of aminoacyl-tRNA. The drug is covalently bonded to the existing growing peptide chain via peptidyl transferase, thereby impairing the rest of protein synthesis and leading to early polypeptide truncation. Where is the most likely site that this process occurs?", "answer": "P site", "options": {"A": "30S small subunit", "B": "40S small subunit", "C": "A site", "D": "E site", "E": "P site"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 22-year-old man comes to the physician because of multiple nodules on his hands that first appeared a few months ago. He works as a computer game programmer. His father died of a myocardial infarction at 37 years of age, and his mother has rheumatoid arthritis. A photograph of the lesions is shown. The nodules are firm, mobile, and nontender. Which of the following is the most likely mechanism underlying this patient's skin findings?", "answer": "Extravasation of lipoproteins", "options": {"A": "Deposition of triglycerides", "B": "Fibrinoid necrosis", "C": "Crystallization of monosodium urate", "D": "Uncontrolled adipocyte growth", "E": "Extravasation of lipoproteins"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 25-year-old man is brought to the emergency department 30 minutes after collapsing during soccer practice. His father died of sudden cardiac arrest at the age of 36 years. The patient appears well. His pulse is 73/min and blood pressure is 125/78 mm Hg. Cardiac examination is shown. An ECG shows large R waves in the lateral leads and deep S waves in V1 and V2. Further evaluation is most likely to show which of the following?", "answer": "Asymmetric septal hypertrophy", "options": {"A": "Monoclonal light chain deposition in the myocardium", "B": "Aortic root dilatation", "C": "Eccentric left ventricular dilation", "D": "Asymmetric septal hypertrophy", "E": "Mitral valve fibrinoid necrosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old man presents with a 3-day history of right-sided flank pain due to a lodged ureteral stone. What changes would be expected to be seen at the level of glomerular filtration?", "answer": "Increase in Bowman's space hydrostatic pressure", "options": {"A": "Increase in glomerular capillary oncotic pressure", "B": "Increase in Bowman's space capillary oncotic pressure", "C": "Increase in Bowman's space hydrostatic pressure", "D": "Increase in filtration fraction", "E": "No change in filtration fraction"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old man is brought to the emergency department by police at 2:00 AM. They picked him up from a local nightclub, where he was yelling and threatening to fight the staff. A review of his medical record is unremarkable. At the hospital, his behavior continues to be agitated and bizarre. His temperature is 37.0°C (98.6°F), the blood pressure is 162/98 mm Hg, the heart rate is 120/min, the respiratory rate is 18/min, and the oxygen saturation is 99% on room air. The physical exam is notable for agitation, but otherwise, he appears healthy. His thin nasal mucosa oozes blood and his pupils are 2mm, equal, and reactive to light. His speech is pressured and bizarre. He insists the hospital should let him go because “I am in the FBI”. Urine toxicology is sent to the laboratory for analysis. Which of the following is the most likely cause of this patient's presentation?", "answer": "Cocaine intoxication", "options": {"A": "Acute manic episode", "B": "Cocaine intoxication", "C": "Phencyclidine (PCP) intoxication", "D": "Tetrahydrocannabinol (THC) intoxication", "E": "Thyrotoxicosis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 33-year-old man presents to a physician with a 3-year history of gradually worsening tics and difficulty walking. He was last seen by the physician 5 years ago for anxiety and has been purchasing anti-anxiety medications from an internet website without a prescription because he cannot afford to pay for the office visits. Now he says his anxiety is somewhat controlled, but the motor difficulties are making it difficult for him to work and socialize. His family history is unknown because his parents died in an automobile accident when he was an infant. He grew up in foster care and was always a bright child. An MRI of the brain is ordered, which shows prominent atrophy of the caudate nucleus. Repeats of which of the following trinucleotides are most likely responsible for this patient’s disorder?", "answer": "CAG", "options": {"A": "CCG", "B": "CGG", "C": "GAA", "D": "CAG", "E": "CTG"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman comes to the physician because of sadness that started 6 weeks after her 9-month-old daughter was born. Since then, she has not returned to work. Her daughter usually sleeps through the night, but the patient still has difficulty staying asleep. She is easily distracted from normal daily tasks. She used to enjoy cooking, but only orders delivery or take-out now. She says that she always feels too exhausted to do so and does not feel hungry much anyway. The pregnancy of the patient's child was complicated by gestational diabetes. The child was born at 36-weeks' gestation and has had no medical issues. The patient has no contact with the child's father. She is not sexually active. She does not smoke, drink alcohol, or use illicit drugs. She is 157 cm (5 ft 1 in) tall and weighs 47 kg (105 lb); BMI is 20 kg/m2. Vital signs are within normal limits. She is alert and cooperative but makes little eye contact. Physical examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Major depressive disorder", "options": {"A": "Disruptive mood dysregulation disorder", "B": "Adjustment disorder", "C": "Depression with peripartum-onset", "D": "Major depressive disorder", "E": "Normal behavior"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old woman comes to the physician because of a 3-month history of pain in her right thumb and wrist that radiates to her elbow. It is worse when she holds her infant son and improves with the use of an ice pack. Six months ago, she slipped on a wet floor and fell on her right outstretched hand. Her mother takes methotrexate for chronic joint pain. The patient takes ibuprofen as needed for her current symptoms. Examination of the right hand shows tenderness over the radial styloid with swelling but no redness. There is no crepitus. Grasping her right thumb and exerting longitudinal traction toward the ulnar side elicits pain. Range of motion of the finger joints is normal. There is no swelling, redness, or tenderness of any other joints. Which of the following is the most likely diagnosis?", "answer": "De Quervain tenosynovitis", "options": {"A": "De Quervain tenosynovitis", "B": "Swan neck deformity", "C": "Mallet finger", "D": "Carpal tunnel syndrome", "E": "Stenosing tenosynovitis\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman comes to the physician because of bothersome hair growth on her face and abdomen over the past 8 years. She does not take any medications. She is 163 cm (5 ft 4 in) tall and weighs 85 kg (187 lb); BMI is 32 kg/m2. Physical examination shows coarse dark hair on the upper lip and periumbilical and periareolar skin. Her external genitalia appear normal. Her serum follicle-stimulating hormone, luteinizing hormone, and testosterone are within the reference range. A urine pregnancy test is negative. Which of the following is the most appropriate pharmacotherapy for this patient's condition at this time?", "answer": "Oral contraceptive", "options": {"A": "Prednisone", "B": "Leuprolide", "C": "Ketoconazole", "D": "Oral contraceptive", "E": "Metformin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man is brought to the emergency department 20 minutes after being rescued from a fire in his apartment complex. He thinks he might have briefly lost consciousness while he was trapped in a smoke-filled room before firefighters were able to free him 20 minutes later. He reports headache, dizziness, and occasional cough. He has no difficulty breathing, speaking, or swallowing. He appears mildly uncomfortable and agitated. His temperature is 36.4°C (97.5°F), pulse is 90/min, respirations are 16/min, and blood pressure is 155/68 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 92%. Breath sounds are coarse. The remainder of the examination shows no abnormalities. Arterial blood gas analysis on room air shows :\npH 7.30\nPCO2 38 mm Hg\nPO2 70 mm Hg\nHCO3- 18 mEq/L\nCOHb 2% (N < 3)\nIn addition to oxygen supplementation with a non-rebreather mask, which of the following is the most appropriate next step in management?\"", "answer": "Administration of intravenous hydroxycobalamin", "options": {"A": "Administration of intravenous dimercaprol", "B": "Hyperbaric oxygen therapy", "C": "Administration of methylene blue", "D": "Administration of intravenous hydroxycobalamin", "E": "Administration of N-acetylcysteine\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 33-year-old man is brought to the emergency department by his mother because of erratic behavior over the past 6 months. He spends most of his time alone in his room because he believes he is being followed by the Secret Service. He was fired from his job 3 months ago after threatening a colleague. He appears suspicious of his surroundings and asks the doctor questions about “the security of the hospital.” The patient exhibits a flat affect. During physical examination, he tells the doctor that he has a gun at home and plans to shoot his neighbor, whom he thinks is working for the Secret Service. Which of the following is the most appropriate action by the doctor?", "answer": "Warn the person at risk and inform law enforcement", "options": {"A": "Administer haloperidol and request a psychiatric consultation", "B": "Discuss the diagnosis and therapy plan with the patient's mother", "C": "Inform security and law enforcement", "D": "Warn the person at risk and inform law enforcement", "E": "Request a court order to override the patient's right to confidentiality"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old man with a history of congestive heart failure presents to his cardiologist for a follow-up visit. His past medical history is notable for diabetes mellitus, hypertension, and obesity. He takes metformin, glyburide, aspirin, lisinopril, and metoprolol. He has a 40 pack-year smoking history and drinks alcohol socially. His temperature is 99.1°F (37.2°C), blood pressure is 150/65 mmHg, pulse is 75/min, and respirations are 20/min. Physical examination reveals bilateral rales at the lung bases and 1+ edema in the bilateral legs. The physician decides to start the patient on an additional diuretic but warns the patient about an increased risk of breast enlargement. Which of the following is the most immediate physiologic effect of the medication in question?", "answer": "Decreased sodium reabsorption in the collecting duct", "options": {"A": "Decreased bicarbonate reabsorption in the proximal convoluted tubule", "B": "Decreased sodium reabsorption in the thick ascending limb", "C": "Decreased sodium reabsorption in the distal convoluted tubule", "D": "Decreased sodium reabsorption in the collecting duct", "E": "Decreased renin enzyme activity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old girl is brought to the emergency department for 2 days of abdominal pain and watery diarrhea. This morning her stool had a red tint. She and her parents visited a circus 1 week ago. The patient attends daycare. Her immunizations are up-to-date. Her temperature is 38°C (100.4°F), pulse is 140/min, and blood pressure is 80/45 mm Hg. Abdominal examination shows soft abdomen that is tender to palpation in the right lower quadrant with rebound. Stool culture grows Yersinia enterocolitica. Exposure to which of the following was the likely cause of this patient's condition?", "answer": "Undercooked pork", "options": {"A": "Undercooked pork", "B": "Undercooked poultry", "C": "Home-canned food", "D": "Unwashed vegetables", "E": "Deli meats"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 50-year-old man is brought in by ambulance to the emergency department with difficulty breathing and speaking. His wife reports that he might have swallowed a fishbone. While taking his history the patient develops a paroxysmal cough. Visualization of his oropharynx and larynx shows a fishbone lodged in the right piriform recess. After successfully removing the fishbone the patient feels comfortable, but he is not able to cough like before. Damage to which of the following nerves is responsible for the impaired cough reflex in this patient?", "answer": "Internal laryngeal nerve", "options": {"A": "External laryngeal nerve", "B": "Internal laryngeal nerve", "C": "Recurrent laryngeal nerve", "D": "Inferior laryngeal nerve", "E": "Superior laryngeal nerve"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old male presents to the ER with abdominal discomfort and malaise over the past 2 weeks. He states he is married and monogamous. He has a temperature of 39.4°C (102.9°F) and complains of night sweats as well. On physical exam, he has an enlarged spleen with mild tenderness and pale nail beds. There is mild tonsillar erythema and the pulmonary exam demonstrates scattered crackles. A complete blood count demonstrates anemia, thrombocytopenia, and leukocytosis with lymphocytic predominance. A bone marrow aspiration is scheduled the next morning based on the peripheral blood smear findings but was inconclusive due to a low yield. The patient was admitted to the hospital due to the anemia and given a transfusion of packed red blood cells and wide spectrum antibiotics. He is released home the next day with instructions for primary care follow-up. Which of the following laboratory findings is most reliably positive for the primary cause of this illness?", "answer": "Tartrate-resistant acid phosphatase (TRAP)", "options": {"A": "Rapid streptococcal antigen", "B": "Quantiferon Gold", "C": "Monospot", "D": "Tartrate-resistant acid phosphatase (TRAP)", "E": "CD 25"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old man comes to the emergency department because of epigastric pain and multiple episodes of vomiting for 4 hours. Initially, the vomit was yellowish in color, but after the first couple of episodes it was streaked with blood. He had 2 episodes of vomiting that contained streaks of frank blood on the way to the hospital. He has been hospitalized twice in the past year for acute pancreatitis. He drinks 2 pints of vodka daily but had over 4 pints during the past 12 hours. He takes naproxen for his 'hangovers.' He appears uncomfortable. His temperature is 37°C (99.1°F), pulse is 105/min, and blood pressure is 110/68 mm Hg. Examination shows dry mucous membranes and a tremor of his hands. The abdomen is soft and shows tenderness to palpation in the epigastric region; there is no organomegaly. Cardiopulmonary examination shows no abnormalities. Rectal examination is unremarkable. His hemoglobin concentration is 11.3 g/dL and hematocrit concentration is 40%. Which of the following is the most likely cause of this patient's findings?", "answer": "Mucosal tear at the gastroesophageal junction", "options": {"A": "Transmural tear of the lower esophagus", "B": "Pseudoaneurysm of the gastroduodenal artery", "C": "Inflammation of the esophageal wall", "D": "Mucosal tear at the gastroesophageal junction", "E": "Neoplastic growth at the gastroesophageal junction"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old girl comes to the physician because of a 3-week history of nausea, increased urinary frequency, and breast tenderness. She has never had a menstrual period. She is actively involved in her school's track and field team. She is 173 cm (5 ft 8 in) tall and weighs 54 kg (120 lb); BMI is 18 kg/m2. Her breast and pubic hair development are at Tanner stage 5. Which of the following serum assays is the most appropriate next step in the diagnosis of this patient's condition?", "answer": "Human chorionic gonadotropin", "options": {"A": "Estriol", "B": "Thyrotropin", "C": "Human chorionic gonadotropin", "D": "Luteinizing hormone", "E": "Prolactin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old man presents to his primary care provider complaining of intermittent stomach pain, non-bloody diarrhea, and weight loss for the last 3 months. He has occasional abdominal pain and fever. This condition makes studying difficult. He has tried omeprazole and dietary changes with no improvement. Past medical history is significant for occasional pain in the wrists and knees for several years. He takes ibuprofen for pain relief. His temperature is 38°C (100.4°F). On mental status examination, short-term memory is impaired. Attention and concentration are reduced. Examination shows no abnormalities or tenderness of the wrists or knees. There are no abnormalities on heart and lung examinations. Abdominal examination is normal. Upper endoscopy shows normal stomach mucosa but in the duodenum, there is pale yellow mucosa with erythema and ulcerations. Biopsies show infiltration of the lamina propria with periodic acid-Schiff (PAS)-positive macrophages. Which of the following best explains these findings?", "answer": "Whipple’s disease", "options": {"A": "Celiac disease", "B": "Crohn’s disease", "C": "Giardia lamblia infection", "D": "Whipple’s disease", "E": "Wilson’s disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 60-year-old woman is brought to the emergency department by her husband because of worsening shortness of breath over the past 2 days. Last week, she had a sore throat and a low-grade fever. She has coughed up white sputum each morning for the past 2 years. She has hypertension and type 2 diabetes mellitus. She has smoked 2 packs of cigarettes daily for 35 years. Current medications include metformin and lisinopril. On examination, she occasionally has to catch her breath between sentences. Her temperature is 38.1°C (100.6°F), pulse is 85/min, respirations are 16/min, and blood pressure is 140/70 mm Hg. Expiratory wheezes with a prolonged expiratory phase are heard over both lung fields. Arterial blood gas analysis on room air shows:\npH 7.33\nPCO2 53 mm Hg\nPO2 68 mm Hg\nAn x-ray of the chest shows hyperinflation of bilateral lung fields and flattening of the diaphragm. Which of the following additional findings is most likely in this patient?\"", "answer": "Decreased urinary bicarbonate excretion", "options": {"A": "Increased urine osmolar gap", "B": "Decreased urinary bicarbonate excretion", "C": "Increased urinary pH", "D": "Increased serum anion gap", "E": "Decreased urinary chloride concentration"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old nulliparous woman with polycystic ovary syndrome comes to the physician for a pelvic examination and Pap smear. Last year she had a progestin-releasing intrauterine device placed. Menarche occurred at the age of 10 years. She became sexually active at the age of 14 years. Her mother had breast cancer at the age of 51 years. She is 165 cm (5 ft 5 in) tall and weighs 79 kg (174 lb); BMI is 29 kg/m2. Examination shows mild facial acne. A Pap smear shows high-grade cervical intraepithelial neoplasia. Which of the following is this patient's strongest predisposing factor for developing this condition?", "answer": "Early onset of sexual activity", "options": {"A": "Early onset of sexual activity", "B": "Obesity", "C": "Early menarche", "D": "Family history of cancer", "E": "Polycystic ovary syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old girl comes to the physician for a scheduled colonoscopy. She was diagnosed with familial adenomatous polyposis at the age of 13 years. Last year, her flexible sigmoidoscopy showed 12 adenomatous polyps (< 6 mm) that were removed endoscopically. Her father and her paternal grandmother were diagnosed with colon cancer at the age of 37 and 39 years, respectively. The patient appears nervous but otherwise well. Her vital signs are within normal limits. Examination shows no abnormalities. A complete blood count and serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. A colonoscopy shows hundreds of diffuse 4–9 mm adenomatous polyps covering the colon and > 30 rectal adenomas. Which of the following is the most appropriate next step in management?", "answer": "Proctocolectomy with ileoanal anastomosis", "options": {"A": "Repeat colonoscopy in 6 months", "B": "Endoscopic biopsy of polyps", "C": "Proctocolectomy with ileoanal anastomosis", "D": "Folinic acid (leucovorin) + 5-Fluorouracil + oxaliplatin therapy", "E": "CT scan of the abdomen with contrast"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A codon is an mRNA sequence consisting of 3 nucleotides that codes for an amino acid. Each position can be made up of any 4 nucleotides (A, U, G, C); therefore, there are a total of 64 (4 x 4 x 4) different codons that can be created but they only code for 20 amino acids. This is explained by the wobble phenomenon. One codon for leucine is CUU, which of the following can be another codon coding for leucine?", "answer": "CUA", "options": {"A": "AUG", "B": "UAA", "C": "CCC", "D": "CCA", "E": "CUA"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A researcher is conducting a study to compare fracture risk in male patients above the age of 65 who received annual DEXA screening to peers who did not receive screening. He conducts a randomized controlled trial in 900 patients, with half of participants assigned to each experimental group. The researcher ultimately finds similar rates of fractures in the two groups. He then notices that he had forgotten to include 400 patients in his analysis. Including the additional participants in his analysis would most likely affect the study's results in which of the following ways?", "answer": "Increased probability of rejecting the null hypothesis when it is truly false", "options": {"A": "Decreased significance level of results", "B": "Wider confidence intervals of results", "C": "Increased probability of committing a type II error", "D": "Increased probability of rejecting the null hypothesis when it is truly false", "E": "Increased external validity of results"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old woman with bipolar disorder and schizophrenia presents to the emergency room stating that she is pregnant. She says that she has been pregnant since she was 20 years old and is expecting a baby now that she is breathing much harder and feeling more faint with chest pain caused by deep breaths. Her hospital medical record shows multiple negative pregnancy tests over the past 5 years. The patient has a 20 pack-year smoking history. Her temperature is 98°F (37°C), blood pressure is 100/60 mmHg, pulse is 110/min, respirations are 28/min, and oxygen saturation is 90% on room air. Her fingerstick glucose is 100 mg/dL. She has a large abdominal pannus which is soft and nontender. Her legs are symmetric and non-tender. Oxygen is provided via nasal cannula. Her urine pregnancy test comes back positive and an initial chest radiograph is unremarkable. What is the next best step in diagnosis?", "answer": "Ventilation-perfusion scan", "options": {"A": "CT angiogram", "B": "D-dimer", "C": "Psychiatry consult for pseudocyesis", "D": "Ultrasound", "E": "Ventilation-perfusion scan"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 71-year-old man comes to the physician because of a 2-week history of fatigue and a cough productive of a blood-tinged phlegm. Over the past month, he has had a 5.0-kg (11-lb) weight loss. He has hypertension and type 2 diabetes mellitus. Eight months ago, he underwent a kidney transplantation. The patient does not smoke. His current medications include lisinopril, insulin, prednisone, and mycophenolate mofetil. His temperature is 38.9°C (102.1°F), pulse is 88/min, and blood pressure is 152/92 mm Hg. Rhonchi are heard at the right lower lobe of the lung on auscultation. There is a small ulceration on the left forearm. An x-ray of the chest shows a right lung mass with lobar consolidation. Antibiotic therapy with levofloxacin is started. Three days later, the patient has a seizure and difficulty coordinating movements with his left hand. An MRI of the brain shows an intraparenchymal lesion with peripheral ring enhancement. Bronchoscopy with bronchoalveolar lavage yields weakly acid-fast, gram-positive bacteria with branching, filamentous shapes. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Trimethoprim/sulfamethoxazole", "options": {"A": "Rifampin, isoniazid, pyrazinamide, and ethambutol", "B": "Vancomycin", "C": "Piperacillin/tazobactam", "D": "Trimethoprim/sulfamethoxazole", "E": "Erythromycin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 61-year-old-male underwent deceased donor liver transplantation 3 weeks ago. During his follow up visit he complains of nausea and abdominal pain. He has been taking all of his medications as prescribed. He has a history of alcohol abuse and his last drink was one year ago. He does not smoke cigarettes and lives at home with his wife. On physical examination temperature is 98.6°F (37°C), blood pressure is 115/80 mmHg, pulse is 90/min, respirations are 18/min, and pulse oximetry is 99% on room air. He has scleral icterus and a positive fluid wave. Liver function tests are as follows:\n\nAlkaline phosphatase: 110 U/L\nAspartate aminotransferase (AST, GOT): 100 U/L\nAlanine aminotransferase (ALT, GPT): 120 U/L\nBilirubin total: 2.2 mg/dL\n\nLiver biopsy shows mixed dense interstitial lymphocytic infiltrates in the portal triad. What is the mechanism of this reaction?", "answer": "CD8+ T lymphocytes reacting against donor MHCs", "options": {"A": "CD8+ T lymphocytes reacting against donor MHCs", "B": "CD4+ T lymphocytes reacting against recipient APCs", "C": "Pre-existing recipient antibodies", "D": "Acute viral infection", "E": "Grafted T lymphocytes reacting against host"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old male patient with a history of recurrent nephrolithiasis and chronic lower back pain presents to the ER with severe, sudden-onset, upper abdominal pain. The patient is febrile, hypotensive, and tachycardic, and is rushed to the OR for exploratory laporotomy. Surgery reveals that the patient has a perforated gastric ulcer. Despite appropriate therapy, the patient expires, and subsequent autopsy reveals multiple ulcers in the stomach, duodenum, and jejunum. The patient had been complaining of abdominal pain and diarrhea for several months but had only been taking ibuprofen for his lower back pain for the past 3 weeks. What is the most likely cause of the patient's presentation?", "answer": "A gastrin-secreting tumor of the pancreas", "options": {"A": "A gastrin-secreting tumor of the pancreas", "B": "A vasoactive-intestinal-peptide (VIP) secreting tumor of the pancreas", "C": "Cytomegalovirus infection", "D": "H. pylori infection", "E": "Chronic NSAID use"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman comes to the physician because of pain and stiffness in both of her hands for the past 3 weeks. The pain is most severe early in the day and does not respond to ibuprofen. She has no history of serious illness and takes no medications. Vital signs are within normal limits. Examination shows swelling and tenderness of the wrists and metacarpophalangeal joints bilaterally. Range of motion is decreased due to pain. There are subcutaneous, nontender, firm, mobile nodules on the extensor surface of the forearm. Which of the following is the most appropriate pharmacotherapy for this patient's current symptoms?", "answer": "Prednisone", "options": {"A": "Methotrexate", "B": "Adalimumab", "C": "Colchicine", "D": "Sulfasalazine", "E": "Prednisone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A peripheral artery is found to have 50% stenosis. Therefore, compared to a normal artery with no stenosis, by what factor has the flow of blood been decreased?", "answer": "16", "options": {"A": "2", "B": "4", "C": "8", "D": "16", "E": "32"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman presents to her physician requesting the chickenpox vaccine. She is also complaining of nausea, malaise, and moderate weight gain. She developed these symptoms gradually over the past 2 weeks. She reports no respiratory or cardiovascular disorders. Her last menstruation was about 6 weeks ago. She has one sexual partner and uses a natural planning method for contraception. Her vital signs include: blood pressure 110/70 mm Hg, heart rate 92/min, respiratory rate 14/min, and temperature 37.2℃ (99℉). The physical examination shows non-painful breast engorgement and nipple hyperpigmentation. There is no neck enlargement and no palpable nodules in the thyroid gland. The urine beta-hCG is positive. What is the proper recommendation regarding chickenpox vaccination in this patient?", "answer": "Confirm pregnancy with serum beta-hCG and if positive, postpone administration of the vaccine until after completion of the pregnancy.", "options": {"A": "Schedule the vaccination.", "B": "Perform varicella viral load and schedule the vaccine based on these results.", "C": "Confirm pregnancy with serum beta-hCG and if positive, schedule the patient for pregnancy termination.", "D": "Confirm pregnancy with serum beta-hCG and if positive, postpone administration of the vaccine until after completion of the pregnancy.", "E": "Confirm pregnancy with serum beta-hCG and if positive delay administration of the vaccine until the third trimester."}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 20-year-old Caucasian male presents with recurrent nosebleeds. Complete history reveals his father died in his 40's after an intracranial hemorrhage and two of his father's five siblings have also had recurrent nosebleeds. Which of the following would you expect to find in this patient?", "answer": "Mucosal arteriovenous malformations", "options": {"A": "Retinal hemangioblastoma", "B": "Renal cell carcinoma", "C": "Mucosal arteriovenous malformations", "D": "Vestibular schwannoma", "E": "Cafe-au-lait spots"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man presents with a bilateral lower leg edema. The patient reports it developed gradually over the past 4 months. The edema is worse in the evening and improves after sleeping at night or napping during the day. There are no associated pain or sensitivity changes. The patient also notes dyspnea on usual exertion such as working at his garden. The patient has a history of a STEMI myocardial infarction 9 months ago treated with thrombolysis with an unremarkable postprocedural course. His current medications include atorvastatin 10 mg, aspirin 81 mg, and metoprolol 50 mg daily. He works as a barber at a barbershop, has a 16-pack-year history of smoking, and consumes alcohol in moderation. The vital signs include: blood pressure 130/80 mm Hg, heart rate 63/min, respiratory rate 14/min, and temperature 36.8℃ (98.2℉). The lungs are clear to auscultation. Cardiac examination shows dubious S3 and a soft grade 1/6 systolic murmur best heard at the apex of the heart. Abdominal examination reveals hepatic margin 1 cm below the costal margin. There is a 2+ bilateral pitting lower leg edema. The skin over the edema is pale with no signs of any lesions. There is no facial or flank edema. The thyroid gland is not enlarged. Which of the following tests is most likely to reveal the cause of the patient’s symptoms?", "answer": "Echocardiography", "options": {"A": "Doppler color ultrasound of the lower extremity", "B": "D-dimer measurement", "C": "Soft tissue ultrasound of the lower extremities", "D": "T4 and thyroid-stimulating hormone assessment", "E": "Echocardiography"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 39-year-old G3P0 woman presents for preconception counseling and evaluation. The patient’s past medical history reveals hypertension and type 1 diabetes. She is currently on an insulin pump and medications for hypertension including labetalol. Her blood pressure is 130/85 mm Hg; pulse, 76/min; and BMI, 26 kg/m2. Her most recent HbA1c is 6.5%. Her previous pregnancies ended in spontaneous abortion during the 1st trimester despite adequate prenatal care. The patient intends to have a healthy pregnancy and desires to learn more about the risk factors that potentially trigger miscarriage. Which of the following maternal risk factors is most likely associated with early pregnancy loss?", "answer": "Age", "options": {"A": "Chronic hypertension", "B": "Diabetes", "C": "Infection", "D": "Age", "E": "Hypercoagulable state"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 71-year-old woman comes to the physician because of palpitations and shortness of breath that started 3 days ago. She has hypertension and congestive heart failure. Her pulse is 124/min, and blood pressure is 130/85 mm Hg. Cardiac examination shows an irregularly irregular rhythm without any murmurs. An ECG shows a narrow-complex tachycardia without P waves. The patient is prescribed a prophylactic medication that can be reversed with idarucizumab. The expected beneficial effect of the prescribed drug is most likely due to which of the following effects?", "answer": "Direct inhibition of thrombin", "options": {"A": "Induction of conformational change in antithrombin III", "B": "Inhibition of thrombocyte phosphodiesterase III", "C": "Irreversible inhibition of GPIIb/IIIa complex", "D": "Direct inhibition of factor Xa", "E": "Direct inhibition of thrombin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 5-year-old African American female has experienced recurrent respiratory infections. To determine how well her cell-mediated immunity is performing, a Candida skin injection is administered. After 48 hours, there is no evidence of induration at the injection site. Of the following cell types, which one would have mediated the reaction?", "answer": "T-cells", "options": {"A": "Plasma cells", "B": "Basophils", "C": "T-cells", "D": "Mast cells", "E": "Fibroblasts"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old man comes to the physician for an annual health maintenance examination. He has a history of stable angina, gout, and hypertension. His medications include lisinopril and aspirin. He has smoked a pack of cigarettes daily for 20 years. He drinks 5–6 beers on the weekends. His blood pressure is 150/85 mm Hg. Laboratory studies show a total cholesterol of 276 mg/dL with an elevated low-density lipoprotein (LDL) concentration and low high-density lipoprotein (HDL) concentration. Administration of which of the following agents is the most appropriate next step in management?", "answer": "HMG-CoA reductase inhibitor", "options": {"A": "HMG-CoA reductase inhibitor", "B": "Peroxisome proliferator-activated receptor alpha activator", "C": "Cholesterol absorption inhibitor", "D": "Proprotein convertase subtilisin kexin 9 inhibitor", "E": "Bile acid resin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the pediatrician’s office with her 17-year-old daughter. She tells the physician that she developed Sjögren’s syndrome when she was her daughter’s age, and that she is concerned about her daughter developing the same condition. The girl appears to be in good health, with no signs or symptoms of the disease or pathology. Which of the following antibodies will most likely be positive if the woman’s daughter were to develop Sjögren’s syndrome?", "answer": "Anti-SS-B (anti-La) antibodies", "options": {"A": "Anti-cyclic citrullinated antibodies", "B": "Anti-dsDNA antibodies", "C": "Anti-SS-B (anti-La) antibodies", "D": "Anti-histone antibodies", "E": "Anti-topoisomerase (anti-Scl 70) antibodies"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-year-old male presents to his primary care physician complaining of upper abdominal pain. He reports a four-month history of crampy epigastric pain that improves with meals. His past medical history is significant for hypertension that has been well controlled by lisinopril. He does not smoke and drinks alcohol occasionally. His family history is notable for a maternal uncle with acromegaly and a maternal grandfather with parathyroid adenoma requiring surgical resection. Based on clinical suspicion laboratory serum analysis is obtained and shows abnormal elevation of a peptide. This patient most likely has a mutation in which of the following chromosomes?", "answer": "11", "options": {"A": "5", "B": "10", "C": "11", "D": "13", "E": "17"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A group of microbiological investigators is studying bacterial DNA replication in E. coli colonies. While the cells are actively proliferating, the investigators stop the bacterial cell cycle during S phase and isolate an enzyme involved in DNA replication. An assay of the enzyme's exonuclease activity determines that it is active on both intact and demethylated thymine nucleotides. Which of the following enzymes have the investigators most likely isolated?", "answer": "DNA polymerase I", "options": {"A": "DNA ligase", "B": "Telomerase", "C": "DNA polymerase I", "D": "DNA topoisomerase", "E": "Primase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 33-year-old woman comes to the physician because of a 3-week history of fatigue and worsening shortness of breath on exertion. There is no family history of serious illness. She does not smoke. She takes diethylpropion to control her appetite and, as a result, has had a 4.5-kg (10-lb) weight loss during the past 5 months. She is 163 cm (5 ft 4 in) tall and weighs 115 kg (254 lb); BMI is 44 kg/m2. Her pulse is 83/min and blood pressure is 125/85 mm Hg. Cardiac examination shows a loud pulmonary component of the S2. Abdominal examination shows no abnormalities. Which of the following is the most likely underlying cause of this patient's shortness of breath?", "answer": "Hyperplasia of pulmonary vascular walls", "options": {"A": "Hypertrophy of interventricular septum", "B": "Hyperplasia of pulmonary vascular walls", "C": "Blockade of the right bundle branch", "D": "Fibrosis of pulmonary interstitium", "E": "Calcification of the pulmonary valve"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying the outcomes of a malaria outbreak in an endemic region of Africa. 500 men and 500 women with known malaria exposure are selected to participate in the study. Participants with G6PD deficiency are excluded from the study. The clinical records of the study subjects are reviewed and their peripheral blood smears are evaluated for the presence of Plasmodium trophozoites. Results show that 9% of the exposed population does not have clinical or laboratory evidence of malaria infection. Which of the following best explains the absence of infection seen in this subset of participants?", "answer": "Glutamic acid substitution in the β-globin chain", "options": {"A": "Translocation of c-myc gene", "B": "Inherited defect in erythrocyte membrane ankyrin protein", "C": "Defective X-linked ALA synthase gene", "D": "Inherited mutation affecting ribosome synthesis", "E": "Glutamic acid substitution in the β-globin chain"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old man comes to his primary care provider for a routine visit. The patient mentions that while he was cooking 5 days ago, he accidentally cut himself with a meat cleaver and lost the skin at the tip of his finger. After applying pressure and ice, the bleeding stopped and he did not seek treatment. The patient is otherwise healthy and does not take any daily medications. The patient’s temperature is 98.2°F (36.8°C), blood pressure is 114/72 mmHg, pulse is 60/min, and respirations are 12/min. On exam, the patient demonstrates a 0.5 x 0.3 cm wound on the tip of his left third finger. No bone is involved, and the wound is red, soft, and painless. There are no signs of infection. Which of the following can be expected on histopathological examination of the wounded area?", "answer": "Deposition of type III collagen", "options": {"A": "Deposition of type I collagen", "B": "Deposition of type III collagen", "C": "Epithelial cell migration from the wound borders", "D": "Neutrophil migration into the wound", "E": "Platelet aggregates"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An otherwise healthy 56-year-old woman comes to the physician because of a 3-year history of intermittent upper abdominal pain. She has had no nausea, vomiting, or change in weight. Physical examination shows no abnormalities. Laboratory studies are within normal limits. Abdominal ultrasonography shows a hyperechogenic rim-like calcification of the gallbladder wall. The finding in this patient's ultrasonography increases the risk of which of the following conditions?", "answer": "Gallbladder carcinoma", "options": {"A": "Hepatocellular carcinoma", "B": "Gallbladder empyema", "C": "Pyogenic liver abscess", "D": "Gallbladder carcinoma", "E": "Acute pancreatitis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An excisional biopsy is performed and the diagnosis of superficial spreading melanoma is confirmed. The lesion is 1.1 mm thick. Which of the following is the most appropriate next step in management?", "answer": "Surgical excision with 1-2 cm safety margins and sentinel lymph node study", "options": {"A": "Surgical excision with 0.5-1 cm safety margins only", "B": "Surgical excision with 1-2 cm safety margins only", "C": "Surgical excision with 1-2 cm safety margins and sentinel lymph node study", "D": "Surgical excision with 0.5-1 cm safety margins and sentinel lymph node study", "E": "Surgical excision with 1 cm safety margins only\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 52-year-old man comes to the physician for a routine health maintenance examination. He has not seen a physician for 10 years. He works as a telemarketer and does not exercise. Cardiac examination shows a dull, low-pitched sound during late diastole that is best heard at the apex. The sound is loudest in the left lateral decubitus position and during end-expiration. Which of the following is the most likely cause of this finding?", "answer": "Concentric left ventricular hypertrophy", "options": {"A": "Concentric left ventricular hypertrophy", "B": "Dilation of both ventricles", "C": "Fusion of mitral valve leaflets", "D": "Right bundle branch block", "E": "Aortic root dilatation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman comes to the physician because of vaginal discharge for 3 days. She has no dysuria, dyspareunia, pruritus, or burning. The patient is sexually active with two male partners and uses condoms inconsistently. She often douches between sexual intercourse. Pelvic examination shows thin and off-white vaginal discharge. The pH of the discharge is 5.1. Wet mount exam shows a quarter of her vaginal epithelial cells are covered with small coccobacilli. Which of the following is the most appropriate next step in management?", "answer": "Treat the patient with metronidazole", "options": {"A": "Treat the patient with ceftriaxone and azithromycin", "B": "Treat the patient and partners with metronidazole", "C": "Reassurance and follow-up in one week", "D": "Treat the patient with metronidazole", "E": "Treat patient and partners with topical ketoconazole"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 31-year-old man comes to the physician because of a 2-day history of nausea, abdominal discomfort, and yellow discoloration of the eyes. Six weeks ago, he had an episode of fever, joint pain, swollen lymph nodes, and an itchy rash on his trunk and extremities that persisted for 1 to 2 days. He returned from a backpacking trip to Colombia two months ago. His temperature is 39°C (101.8°F). Physical examination shows scleral icterus. Infection with which of the following agents is the most likely cause of this patient's findings?", "answer": "Hepatitis B", "options": {"A": "Hepatitis B", "B": "Enterotoxigenic E. coli", "C": "Borrelia burgdorferi", "D": "Hepatitis A", "E": "Campylobacter jejuni"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old woman comes to the physician because of difficulty walking and dizziness for the past 2 weeks. She has also had fatigue, heartburn, and diarrhea for 4 months. The stools are foul-smelling and do not flush easily. Over the past 4 months, she has had a 2.2-kg (5-lb) weight loss. Her only medication is an over-the-counter antacid. Her mother has autoimmune thyroid disease and Crohn disease. She is 150 cm (4 ft 11 in) tall and weighs 43 kg (95 lb); BMI is 19.1 kg/m2. Vital signs are within normal limits. Examination shows a wide-based gait. Muscle strength and tone are normal in all extremities. Rapid alternating movement of the hands is impaired. The abdomen is soft and there is mild tenderness to palpation in the epigastric area. Her hemoglobin concentration is 11.1 mg/dL, and levels of vitamin E and vitamin D are decreased. Upper endoscopy shows several ulcers in the gastric antrum and the descending duodenum. Which of the following is the most likely underlying mechanism of this patient's symptoms?", "answer": "Inactivation of pancreatic enzymes", "options": {"A": "Autoantibodies against the intestinal mucosa", "B": "Inactivation of pancreatic enzymes", "C": "T. whipplei infiltration of intestinal villi", "D": "Intestinal inflammatory reaction to gluten", "E": "Small intestine bacterial overgrowth"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old woman is brought to the emergency department 30 minutes after developing acute confusion, severe headache, and vomiting. Physical examination shows left-sided numbness. A CT scan of her head shows a large intraparenchymal hemorrhage. Despite appropriate treatment, the patient dies. Autopsy shows multiple small aneurysms of the lenticulostriate arteries of the brain and bilateral hyperplasia of the adrenal glands, limited to the zona glomerulosa. The patient's adrenal condition was most likely associated with which of the following symptoms?", "answer": "Muscle weakness", "options": {"A": "Paroxysmal diaphoresis", "B": "Abdominal striae", "C": "Muscle weakness", "D": "Hirsutism", "E": "Peripheral edema"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 13-year-old African American boy with sickle cell disease is brought to the emergency department with complaints of abdominal pain over the last 24 hours. The pain is situated in the right upper quadrant and is sharp in nature with a score of 8/10 and radiates to tip of the right scapula. He also complains of anorexia and nausea over the past 2 days. He has been admitted into the hospital several times for pain episodes involving his legs, hands, thighs, lower back, and abdomen. His last hospital admission was 4 months ago for acute chest pain, and he was treated with antibiotics, analgesics, and intravenous fluid. He takes hydroxyurea with occasional red blood cell exchange. Both of his parents are in good health. Temperature is 38°C (100.4°F), blood pressure is 133/88 mm Hg, pulse is 102/min, respiratory rate is 20/min, and BMI is 18 kg/m2. On examination, he is in pain with a tender abdomen with painful inspiration. Soft palpation of the right upper quadrant causes the patient to cry out in pain.\nLaboratory test\nComplete blood count\nHemoglobin 8.5 g/dL\nMCV 82 fl\nLeukocytes 13,500/mm3\nPlatelets 145,000/mm3\nBasic metabolic panel\nSerum Na+ 135 mEq/L\nSerum K+ 3.9 mEq/L\nSerum Cl- 101 mEq/L\nSerum HCO3- 23 mEq/L\nLiver function test\nSerum bilirubin 2.8 mg/dL\nDirect bilirubin 0.8 mg/dL\nAST\n30 U/L\nALT 35 U/L\nSerum haptoglobin 23 mg/dL (41–165 mg/dL)\nUltrasonography of abdomen shows the following image. What is the pathogenesis of this ultrasound finding?", "answer": "Chronic hemolysis", "options": {"A": "Increased cholesterol secretion", "B": "Impaired gallbladder emptying", "C": "Decreased bile salt absorption", "D": "Bacterial infection", "E": "Chronic hemolysis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 21-year-old woman presents with irregular menses, acne, and increased body hair growth. She says her average menstrual cycle lasts 36 days and states that she has heavy menstrual bleeding. She had her menarche at the age of 13 years. Her blood pressure is 125/80 mm Hg, heart rate is 79/min, respiratory rate is 14/min, and temperature is 36.7°C (98.1°F). Her body weight is 101.0 kg (222.7 lb) and height is 170 cm (5 ft 7 in). Physical examination shows papular acne on her forehead and cheeks. There are dark hairs present on her upper lip, periareolar region, linea alba, and hips, as well as darkening of the skin on the axilla and posterior neck. Which of the following endocrine abnormalities would also most likely be found in this patient?", "answer": "Insulin resistance", "options": {"A": "Hypothyroidism", "B": "Insulin resistance", "C": "Aldosterone hyperproduction", "D": "Adrenaline hypersecretion", "E": "Hypoestrogenism"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man is brought to the emergency department by his wife because of progressive confusion for the past 2 weeks. He has also had a 4.5-kg (10-lb) weight loss and fatigue during the last 6 months. Physical examination shows enlarged lymph nodes in the right axilla and faint expiratory wheezing in the right middle lung field. He is only oriented to person. Serum studies show a sodium concentration of 125 mEq/L and increased antidiuretic hormone concentration. An x-ray of the chest shows a right-sided hilar mass with mediastinal fullness. A biopsy of the hilar mass is most likely to show cells that stain positive for which of the following?", "answer": "Neuron-specific enolase", "options": {"A": "Desmin", "B": "Neurofilament", "C": "Napsin A", "D": "S-100", "E": "Neuron-specific enolase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An otherwise healthy 17-year-old girl comes to the physician because of multiple patches on her face, hands, abdomen, and feet that are lighter than the rest of her skin. The patches began to appear 3 years ago and have been gradually increasing in size since. There is no associated itchiness, redness, numbness, or pain. She emigrated from India 2 years ago. An image of the lesions on her face is shown. Which of the following is most likely involved in the pathogenesis of this patient's skin findings?", "answer": "Autoimmune destruction of melanocytes", "options": {"A": "Absence of tyrosinase activity", "B": "Infection with Mycobacterium leprae", "C": "Infection with Malassezia globosa", "D": "Defective tuberin protein", "E": "Autoimmune destruction of melanocytes"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 9-year-old boy is brought to the emergency department by his parents after a 2-day history of fever, productive cough, and severe dyspnea. The parents report that the boy had no health problems at birth but developed respiratory problems as an infant that have continued throughout his life, including recurrent pulmonary infections. Vital signs include: temperature of 37.5ºC (99.5ºF), pulse of 105/min, respiratory rate of 34/min, and SpO2 of 87%. Physical examination shows digital clubbing and cyanosis. Chest X-rays show hyperinflation of the lungs and chronic interstitial changes. The boy’s FEV1/FVC ratio is decreased, and his FRC is increased. The resident reviewing his case is studying new gene therapies for this boy’s condition that will reintroduce the gene for which this boy is defective. An important component of this therapy is identifying a vector for the selective introduction of the replacement gene into the human body. Which of the following would be the best vector to provide gene therapy for this boy’s respiratory symptoms?", "answer": "Adenovirus", "options": {"A": "Adenovirus", "B": "Rhinovirus", "C": "Human immunodeficiency virus-1", "D": "Rabies virus", "E": "Coxsackie A virus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old woman presents to the emergency department with severe pain in her legs. She has had these pains in the past but access to a doctor was not readily available in her remote village back home. She and her family have recently moved to the United States. She is seen walking to her stretcher with a broad-based gait. Ophthalmic examination shows an absent pupillary light reflex, and pupillary constriction with accommodation and convergence. What other sign or symptom is most likely present in this patient?", "answer": "Loss of vibration sensation", "options": {"A": "Negative Romberg sign", "B": "Deep tendon hyperreflexia", "C": "Painless ulcerated papules", "D": "Bell's Palsy", "E": "Loss of vibration sensation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man comes to the physician for a follow-up examination. Two weeks ago, he was treated in the emergency department for head trauma after being hit by a bicycle while crossing the street. Neurological examination shows decreased taste on the right anterior tongue. This patient's condition is most likely caused by damage to a cranial nerve that is also responsible for which of the following?", "answer": "Eyelid closure", "options": {"A": "Uvula movement", "B": "Facial sensation", "C": "Eyelid closure", "D": "Tongue protrusion", "E": "Parotid gland salivation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old male presents to his primary care physician complaining of drainage from his left great toe. He has had an ulcer on his left great toe for over eight months. He noticed increasing drainage from the ulcer over the past week. His past medical history is notable for diabetes mellitus on insulin complicated by peripheral neuropathy and retinopathy. His most recent hemoglobin A1c was 9.4%. He has a 25 pack-year smoking history. He has multiple sexual partners and does not use condoms. His temperature is 100.8°F (38.2°C), blood pressure is 150/70 mmHg, pulse is 100/min, and respirations are 18/min. Physical examination reveals a 1 cm ulcer on the plantar aspect of the left great toe surrounded by an edematous and erythematous ring. Exposed bone can be palpated with a probe. There are multiple small cuts and bruises on both feet. A bone biopsy reveals abundant gram-negative rods that do not ferment lactose. The pathogen most likely responsible for this patient’s current condition is also strongly associated with which of the following conditions?", "answer": "Otitis externa", "options": {"A": "Otitis externa", "B": "Gastroenteritis", "C": "Waterhouse-Friedrichsen syndrome", "D": "Rheumatic fever", "E": "Toxic shock syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 69-year-old woman comes to the physician because of a 4-month history of cough with blood-tinged sputum and a 4.5-kg (10-lb) weight loss. She has smoked one pack of cigarettes daily for 38 years. Auscultation of the lungs shows wheezing in the right lung field. An x-ray of the chest shows an irregular lesion with a central cavity in the proximal right lung. A lung biopsy shows malignant cells that express desmoglein and stain positive for cytokeratin. Which of the following findings confers the worst prognosis in this patient?", "answer": "Mediastinal invasion", "options": {"A": "High mitotic activity", "B": "High nucleus to cytoplasmic ratio", "C": "Presence of necrosis", "D": "Mediastinal invasion", "E": "Poor cellular differentiation\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 44-year-old woman presents to the emergency department with confusion starting this morning. Her husband states that she initially complained of abdominal pain, diarrhea, and fatigue after eating. She has vomited 3 times and progressively became more confused. Her past medical history is notable for morbid obesity, diabetes, hypertension, dyslipidemia, a sleeve gastrectomy 1 month ago, and depression with multiple suicide attempts. Her temperature is 98.0°F (36.7°C), blood pressure is 104/54 mmHg, pulse is 120/min, respirations are 15/min, and oxygen saturation is 98% on room air. Her physical exam is notable for generalized confusion. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 3.9 mEq/L\nHCO3-: 24 mEq/L\nBUN: 22 mg/dL\nGlucose: 41 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\nC-peptide level: normal\n\nWhich of the following is the most likely diagnosis?", "answer": "Dumping syndrome", "options": {"A": "Dumping syndrome", "B": "Glipizide overdose", "C": "Insulin overdose", "D": "Malnutrition", "E": "Propranolol overdose"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 69-year-old man is brought to the emergency department because of severe epigastric pain and vomiting that started 30 minutes ago while gardening. His pulse is 55/min, respirations are 30/min, and blood pressure is 90/50 mm Hg. Physical examination shows diaphoresis and jugular venous distention. Crackles are heard in both lower lung fields. An ECG shows P waves independent of QRS complexes and ST segment elevation in leads II, III, and aVF. Coronary angiography is most likely to show narrowing of which of the following vessels?", "answer": "Proximal right coronary artery", "options": {"A": "Left coronary artery", "B": "Proximal right coronary artery", "C": "Left circumflex artery", "D": "Left anterior descending artery", "E": "Posterior interventricular artery"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An HIV-positive patient with a CD4+ count of 45 is receiving recommended first-line treatment for a case of cytomegalovirus retinitis. Coadministration with which of the following agents would be most likely to precipitate a deficiency of neutrophils in this patient?", "answer": "Zidovudine", "options": {"A": "Foscarnet", "B": "Zidovudine", "C": "Efavirenz", "D": "Ritonavir", "E": "Raltegravir"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator studying the immunologic profile of various cells notices that the blood of a test subject agglutinates upon addition of a serum containing antibodies against P blood group antigens. Infection with which of the following pathogens would most likely be prevented by these antibodies?", "answer": "Parvovirus B19", "options": {"A": "Parvovirus B19", "B": "Babesia microti", "C": "Plasmodium vivax", "D": "Epstein Barr virus", "E": "Influenza virus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-month-old boy is brought to the physician by his parents for the evaluation of a rash on his scalp and forehead. The parents report that the rash has been present for several weeks. They state that the rash is sometimes red and scaly, especially when it is cold. The patient was born at 36 weeks' gestation and has generally been healthy since. His father has psoriasis. The patient appears comfortable. Examination shows several erythematous patches on the scalp, forehead, and along the hairline. Some patches are covered by greasy yellow scales. Which of the following is the most likely diagnosis?", "answer": "Seborrheic dermatitis", "options": {"A": "Atopic dermatitis", "B": "Erythroderma", "C": "Seborrheic keratosis", "D": "Allergic contact dermatitis", "E": "Seborrheic dermatitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old woman has dysuria, pyuria, increased frequency of urination, and fever of 1-day duration. She is sexually active. Urine cultures show gram-positive bacteria in clusters that are catalase-positive and coagulase-negative. The patient is started on trimethoprim-sulfamethoxazole. Which of the following characteristics is used to identify the offending organism?", "answer": "Resistance to novobiocin", "options": {"A": "Beta hemolysis", "B": "Resistance to bacitracin", "C": "Sensitivity to novobiocin", "D": "Sensitivity to bacitracin", "E": "Resistance to novobiocin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old man presents to the emergency department with dizziness. He states he has experienced a sustained sensation of the room spinning that is low grade and constant since this morning. The patient occasionally feels nauseous and has been taking diphenydramine to sleep which helps with his symptoms. The patient is generally healthy, has no other medical conditions, and only endorses eating more garlic recently to get over a cold he had a few days ago. His temperature is 98.7°F (37.1°C), blood pressure is 122/81 mmHg, pulse is 82/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam is notable for a healthy man. The patient is sat upright, his head is turned slightly to the right, and he is laid back flat rapidly. This does not provoke any symptoms even when repeated on the left side. A nystagmus is notable on cranial nerve exam as well as bilateral decreased hearing. The patient’s tandem gait is unstable; however, his baseline gait appears unremarkable despite the patient stating he has a sustained sensation of imbalance. Which of the following is the most likely diagnosis?", "answer": "Labyrinthitis", "options": {"A": "Benign paroxysmal positional vertigo", "B": "Labyrinthitis", "C": "Meniere disease", "D": "Vertebrobasilar stroke", "E": "Vestibular neuritis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man presents to his primary care physician complaining of increasing difficulty sleeping over the last 3 months. He reports waking up frequently during the night because he feels an urge to move his legs, and he has a similar feeling when watching television before bed. The urge is relieved by walking around or rubbing his legs. The patient’s wife also notes that she sometimes sees him moving his legs in his sleep and is sometimes awoken by him. Due to his recent sleep troubles, the patient has started to drink more coffee throughout the day to stay awake and reports having up to 3 cups daily. The patient has a past medical history of hypertension and obesity but states that he has lost 10 pounds in the last 3 months without changing his lifestyle. He is currently on hydrochlorothiazide and a multivitamin. His last colonoscopy was when he turned 50, and he has a family history of type II diabetes and dementia. At this visit, his temperature is 99.1°F (37.3°C), blood pressure is 134/81 mmHg, pulse is 82/min, and respirations are 14/min. On exam, his sclerae are slightly pale. Cardiovascular and pulmonary exams are normal, and his abdomen is soft and nontender. Neurologic exam reveals 2+ reflexes in the bilateral patellae and 5/5 strength in all extremities. Which of the following is most likely to identify the underlying etiology of this patient's symptoms?", "answer": "Colonoscopy", "options": {"A": "Dopamine uptake scan of the brain", "B": "Trial of iron supplementation", "C": "Colonoscopy", "D": "Trial of reduction in caffeine intake", "E": "Trial of pramipexole"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old man comes to the physician because of upper abdominal discomfort for 2 weeks. He has had 3–4 episodes of vomiting during this period. Over the last year, he has had frequent episodes of abdominal pain at night that were relieved by eating. He underwent a right shoulder surgery 6 weeks ago. He has no history of serious illness. He has smoked one pack of cigarettes daily for 14 years. He drinks one to two beers daily. He has a history of illicit drug use, but has not used for the past 15 years. He is sexually active with three female partners and uses condoms inconsistently. His only medication is daily naproxen. He returned from a 2-week vacation to Mexico one month ago. He appears uncomfortable. His temperature is 39.5°C (103.1°F), pulse is 90/min, and blood pressure is 110/70 mm Hg. Examination shows a soft abdomen with mild tenderness to palpation in the right upper quadrant. Bowel sounds are normal. Rectal examination is unremarkable. Test of the stool for occult blood is positive. His hemoglobin concentration is 13.1 g/dL, leukocyte count is 23,100/mm3, and platelet count is 230,000/mm3. Abdominal ultrasound shows a 2-cm hypoechoic lesion with some internal echoes in an otherwise normal looking liver. Which of the following is the most likely cause for the sonographic findings?", "answer": "Penetrating duodenal ulcer", "options": {"A": "Penetrating duodenal ulcer", "B": "Acute pancreatitis", "C": "Echinococcus granulosus", "D": "Liver cancer", "E": "Entamoeba histolytica"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old primigravid woman comes to the physician for her initial prenatal visit at 12 weeks' gestation. She has had generalized fatigue and shortness of breath over the past 2 months. She has also had a tingling sensation in her toes for the past month. Three years ago, she was treated for gonorrhea. She follows a strict vegan diet since the age of 13 years. Her temperature is 37°C (98.6°F), pulse is 111/min, and blood pressure is 122/80 mm Hg. Examination shows pale conjunctivae and a shiny tongue. Muscle tone and strength is normal. Deep tendon reflexes are 2+ bilaterally. Sensation to vibration and position is decreased over the upper and lower extremities. When asked to stand, hold her arms in front of her, and close her eyes, she loses her balance and takes a step backward. Which of the following is most likely to have prevented this patient's condition?", "answer": "Vitamin B12 supplementation", "options": {"A": "Calcium supplementation", "B": "Vitamin B12 supplementation", "C": "Thyroxine supplementation", "D": "Penicillin G therapy", "E": "Iron supplementation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 36-year-old woman comes to the physician to discuss contraceptive options. She is currently sexually active with one male partner, and they have not been using any contraception. She has no significant past medical history and takes no medications. She has smoked one pack of cigarettes daily for 15 years. She is allergic to latex and copper. A urine pregnancy test is negative. Which of the following contraceptive methods is contraindicated in this patient?", "answer": "Combined oral contraceptive pill", "options": {"A": "Diaphragm with spermicide", "B": "Progestin-only pill", "C": "Intrauterine device", "D": "Condoms", "E": "Combined oral contraceptive pill"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 68-year-old man is brought to the emergency department because of a severe headache, nausea, and vomiting for 30 minutes. Forty-five minutes ago, he fell and struck his head, resulting in loss of consciousness for 1 minute. After regaining consciousness, he felt well for 15 minutes before the headache began. On arrival, the patient becomes rigid and his eyes deviate to the right; he is incontinent of urine. Intravenous lorazepam is administered and the rigidity resolves. Which of the following is the most likely cause of the patient's condition?", "answer": "Bleeding between dura mater and skull", "options": {"A": "Intracerebral hemorrhage", "B": "Cerebrospinal fluid production/absorption mismatch", "C": "Rupture of bridging veins", "D": "Acute insufficiency of cerebral blood flow", "E": "Bleeding between dura mater and skull"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Three days after undergoing coronary bypass surgery, a 67-year-old man becomes unresponsive and hypotensive. He is intubated, mechanically ventilated, and a central line is inserted. Vasopressin and noradrenaline infusions are begun. A Foley catheter is placed. Six days later, he has high unrelenting fevers. He is currently receiving noradrenaline via an infusion pump. His temperature is 39.6° (102.3°F), pulse is 113/min, and blood pressure is 90/50 mm Hg. Examination shows a sternal wound with surrounding erythema; there is no discharge from the wound. Crackles are heard at both lung bases. Cardiac examination shows an S3 gallop. Abdominal examination shows no abnormalities. A Foley catheter is present. His hemoglobin concentration is 10.8 g/dL, leukocyte count is 21,700/mm3, and platelet count is 165,000/mm3. Samples for blood culture are drawn simultaneously from the central line and peripheral IV line. Blood cultures from the central line show coagulase-negative cocci in clusters on the 8th postoperative day, and those from the peripheral venous line show coagulase-negative cocci in clusters on the 10th postoperative day. Which of the following is the most likely diagnosis in this patient?", "answer": "Central line-associated blood stream infection", "options": {"A": "Central line-associated blood stream infection", "B": "Ventilator-associated pneumonia", "C": "Catheter-associated urinary tract infection", "D": "Bowel ischemia", "E": "Surgical site infection"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 7-year-old boy is brought to the physician because of spells of unresponsiveness and upward rolling of the eyes for 2 months. The episodes start abruptly and last a few seconds. During that time he does not hear anyone’s voice or make any purposeful movements. When the episodes end, he continues what he was doing before the spell. He does not lose his posture or fall to the ground. Episodes occur multiple times during the day. Physical examination shows no abnormal findings. An EEG following hyperventilation shows 3 Hz spike-and-slow-wave discharges. Which of the following is the most appropriate pharmacotherapy at this time?", "answer": "Ethosuximide", "options": {"A": "Ethosuximide", "B": "Lamotrigine", "C": "Oxcarbazepine", "D": "Sodium valproate", "E": "No pharmacotherapy at this time"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old woman comes to the physician because of progressively worsening coordination and involuntary movements in her left hand for the past 6 months. Her husband also reports that she has been withdrawn and apathetic during this period. She is oriented to time, place, and person. Examination shows a bimanual, rhythmic, low-frequency tremor that is more prominent in the left hand. There is normal range of motion in the arms and legs; active movements are very slow. Muscle strength is normal, and there is increased resistance to passive flexion and extension in the limbs. She walks with a shuffling gait and takes small steps. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Neuronal degeneration due to α-synuclein protein misfolding", "options": {"A": "Accumulation of neurotoxic metabolites secondary to hepatocyte damage", "B": "Copper accumulation due to mutations in hepatocyte copper-transporting ATPase", "C": "Neuronal degeneration due to α-synuclein protein misfolding", "D": "Cerebellar ischemia due to chronic hypertension", "E": "Proliferation of beta-adrenergic receptors from excessive circulating T4"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old man is brought to the emergency department 3 hours after rescuing babies and puppies from a burning daycare center. He says that he complains of headache and nausea attributed to running. He is breathing comfortably. What is another likely finding in this patient?", "answer": "Oxygen saturation of 99% on pulse oximetry", "options": {"A": "Oxygen saturation of 86% on pulse oximetry", "B": "Arterial oxygen partial pressure of 20 mmHg", "C": "Oxygen saturation of 99% on pulse oximetry", "D": "Cherry red facial appearance", "E": "Low blood lactate levels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old woman comes to the physician because of a 2-week history of gradually worsening facial and lower extremity swelling. She has had a 4-kg (8.8-lb) weight gain during this time. Her blood pressure is 150/88 mm Hg. Examination shows periorbital edema and 2+ pretibial edema bilaterally. A 24-hour collection of urine shows 4.0 g of proteinuria. Microscopic examination of a kidney biopsy specimen shows thickening of the glomerular basement membrane. Electron microscopy shows dense subepithelial deposits. Further evaluation is most likely to show which of the following?", "answer": "Anti-phospholipase A2 receptor antibodies", "options": {"A": "Anti-phospholipase A2 receptor antibodies", "B": "Anti-myeloperoxidase antibodies", "C": "Anti-streptolysin O antibodies", "D": "Anti-C3 convertase antibodies", "E": "Anti-collagen type IV antibodies"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old boy is brought to the physician for the evaluation of sore throat for the past 2 days. During this period, he has had intermittent nausea and has vomited once. The patient has no cough, hoarseness, or rhinorrhea. He had similar symptoms at the age of 5 years that resolved spontaneously. He is otherwise healthy. His temperature is 37.9°C (100.2°F), pulse is 85/min, and blood pressure is 108/70 mm Hg. Head and neck examination shows an erythematous pharynx with grayish exudates overlying the palatine tonsils. There is no lymphadenopathy. Rapid antigen detection test for group A streptococci is negative. Which of the following is most appropriate next step in the management of this patient?", "answer": "Obtain throat culture\n\"", "options": {"A": "Measurement of antistreptolysin O titer", "B": "Reassurance and follow-up in two weeks", "C": "Measurement of antiviral capsid antigen IgM antibody", "D": "Penicillin V therapy", "E": "Obtain throat culture\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 60-year-old man with known history of chronic obstructive pulmonary disease is brought by ambulance to the emergency department due to shortness of breath. He is out of breath and cannot string a sentence together. The emergency technician suggests that the man tried his tiotropium inhaler multiple times without success. The patient's vitals are as follows: afebrile, BP 90/60, HR 120, RR 24. Oxygen saturation is 90%. An EKG is obtained that shows narrow-complex tachycardia with irregular P waves preceding each QRS complex and irregular PR intervals. What is the best next step in management?", "answer": "Give oxygen immediately", "options": {"A": "Obtain chemistries and complete blood count and observe", "B": "Give labetalol immediately and observe in emergency room", "C": "Give verapamil immediately and admit to floor", "D": "Give oxygen immediately", "E": "Intubate and admit to intensive care uint"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2-year-old girl is brought to the physician by her parents because of clumsiness and difficulty walking. She began to walk at 12 months and continues to have difficulty standing still without support. She also appears to have difficulty grabbing objects in front of her. Over the past year, she has had 5 episodes of sinusitis requiring antibiotic treatment and was hospitalized twice for bacterial pneumonia. Physical examination shows an unstable, narrow-based gait and several hyperpigmented skin patches. Serum studies show decreased levels of IgA and IgG and an increased level of alpha-fetoprotein. Over the next 5 years, which of the following complications is this patient most likely to develop?", "answer": "Conjunctival telangiectasias", "options": {"A": "Chronic eczema", "B": "Conjunctival telangiectasias", "C": "Pes cavus", "D": "Cardiac rhabdomyoma", "E": "Chronic lymphocytic leukemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old woman presents to her primary care physician with fatigue. She reports that over the past 2 months, she has felt increasingly tired despite no changes in her diet or exercise. Her past medical history is notable for obesity, seasonal allergies, and hypertension. She takes ranitidine as needed and hydrochlorothiazide daily. Her family history is notable for colorectal cancer in her mother and maternal uncle, endometrial cancer in her maternal aunt, and ovarian cancer in her maternal grandmother. Her temperature is 98.8°F (37.1°C), blood pressure is 132/71 mmHg, pulse is 89/min, and respirations are 17/min. On exam, she has conjunctival pallor. A stool sample is hemoccult positive. A colonoscopy reveals a fungating hemorrhagic mass in the ascending colon. Which of the following processes is likely impaired in this patient?", "answer": "Mismatch repair", "options": {"A": "Base excision repair", "B": "Homologous recombination", "C": "Mismatch repair", "D": "Non-homologous end joining", "E": "Nucleotide excision repair"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old woman, gravida 2, para 1, at 32 weeks' gestation comes to the physician for a prenatal visit. She reports that she has had frequent headaches and dizziness recently. Pregnancy and delivery of her first child were uncomplicated. There is no personal or family history of serious illness. Medications include folic acid and a multivitamin. Her temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 170/100 mm Hg. Pelvic examination shows a uterus consistent in size with a 32-week gestation. Physical examination shows 2+ edema in the lower extremities. Laboratory studies show:\nHematocrit 37%\nLeukocyte count 9000/mm3\nPlatelet count 60,000/mm3\nSerum\nNa+ 140 mEq/L\nCl- 104 mEq/L\nK+ 4.4 mEq/L\nCreatinine 1.0 mg/dL\nAspartate aminotransferase 20 U/L\nAlanine aminotransferase 20 U/L\nWhich of the following is the most appropriate next step in management?\"", "answer": "Magnesium sulfate and labetalol therapy", "options": {"A": "Magnesium sulfate and labetalol therapy", "B": "Platelet transfusion", "C": "Lisinopril therapy", "D": "Admit the patient to the ICU", "E": "Perform C-section\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Positron emission tomography is conducted and indicates a malignant nodule. Bronchoscopy with transbronchial biopsy is performed and a specimen sample of the nodule is sent for frozen section analysis. The tissue sample is most likely to show which of the following pathohistological findings?", "answer": "Squamous cell carcinoma", "options": {"A": "Large cell carcinoma", "B": "Carcinoid tumor", "C": "Squamous cell carcinoma", "D": "Small cell lung carcinoma", "E": "Metastasis of colorectal cancer"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 43-year-old woman comes to the physician for a 3-month history of redness and itching in both eyes. She has also had swelling and pain in the index and middle fingers of both hands and wrist joints over the past 5 months. She has had multiple dental treatments for oral infections over the past year. She has type 2 diabetes mellitus and eczema. Her sister has vitiligo. Current medications include metformin and a daily multivitamin. Vital signs are within normal limits. Examination shows lichenified lesions over her wrists and knees. Bilateral wrist and first metacarpophalengeal joints show swelling and tenderness; range of motion is limited by pain. Oropharyngeal examination shows dry mucous membranes and multiple dental caries. Ophthalmologic examination is slightly decreased in both eyes. There are multiple corneal punctate spots on fluorescein staining. Laboratory studies show:\nHemoglobin 10.7 g/dL\nLeukocyte count 4,100/mm3\nPlatelet count 155,000/mm3\nErythrocyte sedimentation rate 48 mm/h\nSerum\nCreatinine 1.0 mg/dL\nAnti-nuclear antibody positive\nRheumatoid factor positive\nUrinalysis is within normal limits. This patient's condition is most likely associated with which of the following antibodies?\"", "answer": "Anti-Ro antibodies", "options": {"A": "Anti-U1 RNP antibodies", "B": "Anti-topoisomerase I antibodies", "C": "Anti-Jo1 antibodies", "D": "Anti-Ro antibodies", "E": "Anti-dsDNA antibodies"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old man presents with facial weakness. He says he noticed that his face appeared twisted when he looked in the bathroom mirror this morning. He is otherwise well and does not have any other complaints. He denies any facial pain or paresthesia. No significant past medical history. The patient is afebrile and vital signs are within normal limits. Neurological examination reveals difficulty shutting the right eye tight and inability to bring up the right corner of his mouth when asked to smile. Remainder of the exam, including the left side of the face, is unremarkable. Which of the following is the most likely diagnosis in this patient?", "answer": "Idiopathic facial paralysis", "options": {"A": "Facial nerve schwannoma", "B": "Idiopathic facial paralysis", "C": "Right hemisphere stroke", "D": "Acoustic neuroma", "E": "Left middle cerebral artery stroke"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old woman, gravida 2, para 1, at 14-weeks' gestation comes to the physician for a prenatal visit. Routine first trimester screening shows increased nuchal translucency, decreased β-hCG concentration, and decreased levels of pregnancy-associated plasma protein A. Amniocentesis shows trisomy of chromosome 13. This fetus is at increased risk for which of the following?", "answer": "Cutis aplasia", "options": {"A": "Optic glioma", "B": "Cutis aplasia", "C": "Duodenal atresia", "D": "Cystic hygroma", "E": "Prominent occiput"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 39-year-old man presents with painless swelling of the right testes and a sensation of heaviness. The physical examination revealed an intra-testicular solid mass that could not be felt separately from the testis. After a thorough evaluation, he was diagnosed with testicular seminoma. Which of the following group of lymph nodes are most likely involved?", "answer": "Para-aortic lymph nodes", "options": {"A": "Para-aortic lymph nodes", "B": "Superficial inguinal lymph nodes (medial group)", "C": "Deep inguinal lymph nodes", "D": "Superficial inguinal lymph nodes (lateral group)", "E": "Para-rectal lymph nodes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old man comes to the physician for a health maintenance examination. He feels well. He is 173 cm (5 ft 8 in) tall and weighs 84 kg (185 lb); BMI is 28 kg/m2. His vital signs are within normal limits. Physical examination shows no abnormalities. Serum lipid studies show:\nTotal cholesterol 280 mg/dL\nHDL-cholesterol 30 mg/dL\nLDL-cholesterol 195 mg/dL\nTriglycerides 275 mg/dL\nTreatment with atorvastatin and cholestyramine is initiated. Which of the following changes is most likely induced by both agents?\"", "answer": "Increased LDL receptor expression", "options": {"A": "Increased lipoprotein lipase activity", "B": "Increased LDL receptor expression", "C": "Increased hepatic bile salt synthesis", "D": "Decreased hepatic de novo cholesterol synthesis", "E": "Increased cholesterol levels in hepatocytes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the physician because of fever, fatigue, dry cough, headache, and myalgia over the past week. Two days ago, he developed several painful oral lesions and difficulty swallowing. He underwent kidney transplantation 3 years ago. His temperature is 38.2°C (100.7°F). Physical examination shows bilateral rales, hepatosplenomegaly, and multiple 1–2 cm ulcerative lesions with raised borders in the oral mucosa. A photomicrograph of a liver biopsy specimen is shown. Which of the following is the most likely causal pathogen?", "answer": "Histoplasma capsulatum", "options": {"A": "Aspergillus fumigatus", "B": "Blastomyces dermatitidis", "C": "Histoplasma capsulatum", "D": "Paracoccidioides brasiliensis", "E": "Coccidioides immitis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old woman presents to her primary care provider complaining of numbness and tingling sensations all over her body. After a meticulous history and physical, he found that the patient had recently been on vacation and tried a new sunscreen purchased overseas. The sunscreen contained several chemicals that he was unfamiliar with and after extensive research and consultation with several of his colleagues determined that this was a novel reaction. With the patient’s permission, he decided to write an article that described the main symptoms observed and other findings, how he treated the patient and the follow-up care. His manuscript was published in a peer-reviewed scientific journal. The physician’s publication can be described as which of the following?", "answer": "Case report", "options": {"A": "Case report", "B": "Case series", "C": "Case scenario", "D": "Case definition", "E": "Case control study"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-day-old male newborn is brought to the physician by his mother because of yellowish discoloration of the skin for 1 day. The discoloration first appeared on his face and then spread to his trunk. There have been no changes in his bowel habits or urination. He was born at 38 weeks’ gestation via uncomplicated vaginal delivery. He is exclusively breastfed every 2–3 hours. Examination shows scleral icterus and jaundice of the face, chest, and abdomen. Laboratory studies show:\nHemoglobin 17.6 g/dL\nReticulocytes 0.3%\nMaternal blood group A, Rh-negative\nFetal blood group 0, Rh-positive\nSerum\nBilirubin, total 7 mg/dL\nDirect 0.6 mg/dL\nFree T4 7 μg/dL\nWhich of the following is the most likely diagnosis?\"", "answer": "Physiological neonatal jaundice", "options": {"A": "Congenital hypothyroidism", "B": "Rhesus incompatibility", "C": "Dubin-Johnson syndrome", "D": "Physiological neonatal jaundice", "E": "Biliary atresia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old woman with type 2 diabetes mellitus comes to the physician for a follow-up examination. She previously had been compliant with her diet and medication but has had a 5-kg (11-lb) weight gain since the last visit 6 months ago. She reports that she often misses doses of her metformin. Her hemoglobin A1c is 9.8%. Which of the following is the most appropriate course of action?", "answer": "Schedule more frequent follow-up visits", "options": {"A": "Refer the patient to a dietician", "B": "Schedule more frequent follow-up visits", "C": "Refer the patient to an endocrinologist", "D": "Add glyburide to the medication regimen", "E": "Stop metformin and begin an insulin regimen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 43-year-old man presents to his primary care physician for his yearly check-up exam. He has no new concerns but wants to make sure that his hypertension and diabetes are properly controlled. His past medical history is otherwise unremarkable and his only medications are metformin and lisinopril. He has smoked a pack of cigarettes per day since he was 16 years of age and drinks 3 beers per night. Physical exam is remarkable for a murmur best heard in the 5th intercostal space at the left mid-clavicular line. The murmur is high-pitched and blowing in character and can be heard throughout systole. Which of the following properties is characteristic of this patient's most likely disorder?", "answer": "Radiation of murmur to the axilla", "options": {"A": "Presents with an opening snap", "B": "Radiation of murmur to the axilla", "C": "Radiation of murmur to the neck", "D": "Radiation of murmur to the right sternal border", "E": "Results in mixing of blood between left and right ventricles"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old man is brought to the physician because of inappropriate behavior for the past 6 months. He has been making inappropriate comments and jokes while talking to friends and family members. He was arrested 3 weeks ago while trying to kiss strangers on the street. He has no interest in talking to his daughter or playing with his grandchildren. During this period, he has developed a strong desire for chocolate pudding and potato chips and has gained 10 kg (22 lb). He appears unkempt. Vital signs are within normal limits. Physical examination is unremarkable. Mental status examination shows apathy and a blunt affect. He avoids answering questions and instead comments on the individuals he saw in the waiting room. Mini-Mental State Examination score is 28/30. A complete blood count and serum concentrations of glucose, creatine, and electrolytes are within the reference range. Which of the following is the most likely diagnosis?", "answer": "Frontotemporal dementia", "options": {"A": "Parkinson disease", "B": "Amyotrophic lateral sclerosis", "C": "Normal pressure hydrocephalus", "D": "Wilson disease", "E": "Frontotemporal dementia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old woman comes to the physician because of hearing loss and unsteadiness while standing and walking for the past 2 months. She needs support from a wall to prevent herself from falling. She has not had any recent injuries and has no history of serious illness. Vital signs are within normal limits. Examination shows an unsteady gait. She sways when asked to stand upright with her feet together. She is unable to hear fingers rubbing next to her ears or repeat words whispered in her ears bilaterally. An MRI of the brain shows a 3-cm tumor in the right cerebellopontine angle and a 4.5-cm tumor in the left cerebellopontine angle. This patient is most likely to develop which of the following in the future?", "answer": "Meningioma", "options": {"A": "Renal cell carcinoma", "B": "Telangiectasias", "C": "Optic glioma", "D": "Meningioma", "E": "Astrocytoma\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A study is funded by the tobacco industry to examine the association between smoking and lung cancer. They design a study with a prospective cohort of 1,000 smokers between the ages of 20-30. The length of the study is five years. After the study period ends, they conclude that there is no relationship between smoking and lung cancer. Which of the following study features is the most likely reason for the failure of the study to note an association between tobacco use and cancer?", "answer": "Latency period", "options": {"A": "Effect modification", "B": "Latency period", "C": "Pygmalion effect", "D": "Late-look bias", "E": "Confounding"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old obese male has noticed the gradual development of a soft bulge on his right groin that has been present over the past year and occasionally becomes very tender. He notices that it comes out when he coughs and strains during bowel movements. He is able to push the bulge back in without issue. After examination, you realize that he has an inguinal hernia and recommend open repair with mesh placement. After surgery, the patient returns to clinic and complains of numbness and tingling in the upper part of the scrotum and base of the penis. What nerve was most likely injured during the procedure?", "answer": "Ilioinguinal nerve", "options": {"A": "Iliohypogastric nerve", "B": "Genitofemoral nerve", "C": "Ilioinguinal nerve", "D": "Lateral femoral cutaneous nerve", "E": "Obturator nerve"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old woman comes to the physician for the evaluation of loss of urine for the last several months. She loses small amounts of urine without warning after coughing or sneezing. She also sometimes forgets the names of her relatives. She is retired and lives at an assisted-living facility. She has type 2 diabetes mellitus and hypertension. Her older sister recently received a ventriculoperitoneal shunt. She does not smoke or drink alcohol. Medications include metformin and enalapril. Vital signs are within normal limits. She walks without any problems. Sensation to pinprick and light touch is normal. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Urethral hypermobility", "options": {"A": "Detrusor overactivity", "B": "Loss of sphincter control", "C": "Urethral hypermobility", "D": "Bacterial infection of the urinary tract", "E": "Decreased cerebrospinal fluid absorption"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 78-year-old man is brought to the emergency department because of a 3-week history of productive cough, swelling of the legs and feet, and fatigue. He has had progressive dyspnea on exertion for the past 2 months. Twelve years ago, he received a porcine valve replacement for severe mitral valve regurgitation. He has coronary artery disease, type 2 diabetes mellitus, and hypertension. He has smoked one pack of cigarettes daily for 60 years and drinks one beer daily. Current medications include aspirin, simvastatin, ramipril, metoprolol, metformin, and hydrochlorothiazide. He appears pale. He is 179 cm (5 ft 9 in) tall and weighs 127 kg (279.9 lb); BMI is 41.3 kg/m2. His temperature is 37.1°C (98.9°F), respirations are 22/min, pulse is 96/min, and blood pressure is 146/94 mm Hg. Bilateral basilar rales are heard on auscultation of the lungs. Cardiac examination shows a laterally displaced apical heartbeat. A grade 3/6, decrescendo-crescendo diastolic murmur is heard over the apex. There is bilateral pitting edema of the feet and ankles. The remainder of the examination shows no abnormalities. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Valve degeneration", "options": {"A": "Infective endocarditis", "B": "Chronic obstructive pulmonary disease", "C": "Pneumonia", "D": "Valve degeneration", "E": "Pulmonary embolism"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old girl presents with a sore throat. The patient says symptoms onset acutely 3 days ago and have progressively worsened. She denies any history of cough, nasal congestion or rhinorrhea. No significant past medical history or current medications. The vital signs include: temperature 37.7°C (99.9°F), blood pressure 110/70 mm Hg, pulse 74/min, respiratory rate 20/min, and oxygen saturation 99% on room air. Physical examination is significant for anterior cervical lymphadenopathy. There is edema of the oropharynx and tonsillar swelling but no tonsillar exudate. Which of the following is the next best step in management?", "answer": "Rapid strep test", "options": {"A": "Reassurance", "B": "Rapid strep test", "C": "Ultrasound of the anterior cervical lymph nodes", "D": "Empiric treatment with antibiotics", "E": "Empiric treatment with antivirals"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old woman comes to the physician because of a 2-month history of intermittent bleeding from her vagina. She has no history of serious illness and takes no medications. Pelvic ultrasound shows a thickened endometrial stripe and a left adnexal mass. Endometrial biopsy shows a well-differentiated adenocarcinoma. Laboratory studies show increased levels of inhibin B. Which of the following is the most likely diagnosis?", "answer": "Granulosa cell tumor", "options": {"A": "Yolk sac tumor", "B": "Granulosa cell tumor", "C": "Immature teratoma", "D": "Serous cystadenocarcinoma", "E": "Dysgerminoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old man comes into your office because of pain in his right knee, left elbow, and left wrist. It started about a week ago but has particularly localized to his wrist. The patient states that he has 2 sexual partners. He states he has also had some white discharge from his penis with pruritis and pain during urination. His temperature is 97.6°F (36.4°C), blood pressure is 124/84 mmHg, pulse is 80/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam reveals pain upon palpation of the patient's left wrist which also appears erythematous and swollen. What is the best next step in management for this patient?", "answer": "Arthrocentesis", "options": {"A": "Arthrocentesis", "B": "Azithromycin, ceftriaxone, and vancomycin", "C": "Ibuprofen and observation", "D": "Methotrexate", "E": "MRI"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old college student is diagnosed with acute myelogenous leukemia after presenting with a 3-week history of fever, malaise, and fatigue. He has a history of type 1 diabetes mellitus, multiple middle ear infections as a child, and infectious mononucleosis in high school. He currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and denies any illicit drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 17/min. On physical examination, his pulses are bounding; his complexion is pale, but breath sounds remain clear. A rapidly progressive form of leukemia is identified, and the patient is scheduled to start intravenous chemotherapy. Which of the following treatments should be given to this patient to prevent or decrease the likelihood of developing acute renal failure during treatment?", "answer": "Allopurinol", "options": {"A": "Sulfinpyrazone", "B": "Probenecid", "C": "Allopurinol", "D": "Colchicine", "E": "Indomethacin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 75-year-old woman is brought to a physician’s office by her son with complaints of diarrhea and vomiting for 1 day. Her stool is loose, watery, and yellow-colored, while her vomitus contains partially digested food particles. She denies having blood or mucus in her stools and vomitus. Since the onset of her symptoms, she has not had anything to eat and her son adds that she is unable to tolerate fluids. The past medical history is unremarkable and she does not take any medications regularly. The pulse is 115/min, the respiratory rate is 16/min, the blood pressure is 100/60 mm Hg, and the temperature is 37.0°C (98.6°F). The physical examination shows dry mucous membranes and slightly sunken eyes. The abdomen is soft and non-tender. Which of the following physiologic changes in glomerular filtration rate (GFR), renal plasma flow (RPF), and filtration fraction (FF) are expected?", "answer": "Decreased GFR, decreased RPF, increased FF", "options": {"A": "Increased GFR, increased RPF, increased FF", "B": "Decreased GFR, decreased RPF, increased FF", "C": "Decreased GFR, decreased RPF, no change in FF", "D": "Decreased GFR, decreased RPF, decreased FF", "E": "Increased GFR, decreased RPF, increased FF"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old African-American female presents to your office complaining of dysuria, paresthesias, and blurry vision. Her body mass index is 37.2 kg/m2. Which of the following drugs would most significantly increase the levels of C-peptide in the blood when administered to this patient?", "answer": "Glipizide", "options": {"A": "Metformin", "B": "Insulin", "C": "Glipizide", "D": "Acarbose", "E": "NPH"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought to the emergency department by his mother because of progressive fatigue, abdominal pain, and loss of appetite over the past 3 days. He was treated in the emergency department once in the past year for swelling of his hands and feet. He was adopted as a baby from Sudan and his family history is unknown. He does not take any medication. He is lethargic. His temperature is 37.5°C (99.5°F), pulse is 141/min, respirations are 25/min, and blood pressure is 68/40 mm Hg. Examination shows pale, dry mucous membranes and scleral icterus. Laboratory studies show:\nHemoglobin 7.1 g/dL\nMean corpuscular volume 93 fL\nReticulocyte count 11%\nSerum\nLactate dehydrogenase 194 IU/L\nTotal bilirubin 6.4 mg/dL\nDirect bilirubin 0.5 mg/dL\nHaptoglobin 21 mg/dL (N = 41–165)\nFurther evaluation of this patient is most likely to show which of the following findings?\"", "answer": "Splenomegaly on ultrasound", "options": {"A": "Anti-erythrocyte antibodies on Coombs test", "B": "Pale stool on rectal examination", "C": "Splenomegaly on ultrasound", "D": "Hypocellular bone marrow on biopsy", "E": "Low ferritin level in serum"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old woman with Sjogren’s syndrome presents to her physician for suddenly developed palpitations. She feels more anxious than usual and has had difficulty sleeping well for the past 2 weeks. She has lost 2 kg (4.4 lb) since her last routine appointment 6 months ago. She also has had diarrhea and often feels like her heart is beating very quickly. On physical examination, her skin appears warm and moist. Her reflexes are hyperactive. Her thyroid is moderately enlarged and is non-tender. She has mild dry eyes and dry mouth. Her blood pressure is 136/88 mm Hg, pulse is 76/min, respirations are 17/min and temperature is 36.7°C (98.1°F). Which of the following pathologic findings is this patient likely to have?", "answer": "Chronic lymphocytic thyroiditis", "options": {"A": "Lymphoma", "B": "Silent thyroiditis", "C": "Chronic lymphocytic thyroiditis", "D": "Granulomatous thyroiditis", "E": "Fibrous thyroiditis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old male presents with his wife to his primary care provider for depression and strange movements. His wife reports that her husband has not been himself for the last two months. Whereas he was previously outgoing and “the life of the party,” the patient is now irritable and withdrawn. He is a partner at an accounting firm, but his colleagues are threatening his job if he continues to perform poorly at work. The patient cannot explain the recent changes to his mood and tearfully admits he fears there is something seriously wrong with him. His wife says that she thinks he is getting worse. The patient’s past medical history is significant for hypertension, for which he takes lisinopril. His family history is unknown as he was adopted. The patient met his mother once, and never knew his father but was told he died in his 50's. He drinks a few glasses of wine per week and has never smoked. On physical exam, the patient has a flat affect with facial grimace and sudden jerky movements of his upper extremities.\n\nWhich of the following is most likely to be seen on further workup?", "answer": "Dorsal striatum atrophy on head CT", "options": {"A": "Positive 14-3-3 CSF assay", "B": "Alpha-synuclein aggregates on brain biopsy", "C": "Neurofibrillary tangles on brain biopsy", "D": "Frontotemporal atrophy on head CT", "E": "Dorsal striatum atrophy on head CT"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 64-year-old man presents to the office for an annual physical examination. He has no complaints at this visit. His chart states that he has a history of hypertension, chronic obstructive pulmonary disease (emphysema), Raynaud’s disease, and glaucoma. He is a 30 pack-year smoker. His medications included lisinopril, tiotropium, albuterol, nifedipine, and latanoprost. The blood pressure is 139/96 mm Hg, the pulse is 86/min, the respiration rate is 16/min, and the temperature is 37.2°C (99.1°F). On physical examination, his pupils are equal, round, and reactive to light. The cardiac auscultation reveals an S4 gallop without murmur, and the lungs are clear to auscultation bilaterally. However, the inspection of the chest wall shows an enlarged anterior to posterior diameter. Which of the following is the most appropriate screening test for this patient?", "answer": "Low-dose CT", "options": {"A": "Low-dose CT", "B": "Chest radiograph", "C": "Magnetic resonance imaging", "D": "Bronchoalveolar lavage with cytology", "E": "Pulmonary function tests"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 46-year-old woman presents to the emergency department complaining of abdominal pain, nausea, and vomiting approximately 4 hours after a fatty meal. She reports that this has happened before, but this episode is worse. The vomit was non-bilious and did not contain any blood. She recalls frequent episodes of vague epigastric pain that often wakes her up during the night. Over the counter omeprazole and a small meal or snack would provide some relief in the past. The patient also mentions recent anorexia and early satiety. She takes over the counter ibuprofen several times a week for headaches. Blood pressure is 125/82 mm Hg, pulse is 102/min, and respiratory rate is 19/min. On physical examination, she has hypoactive bowel sounds, and her abdomen seems grossly distended and tympanic on percussion. Which of the following is most consistent with a duodenal ulcer?", "answer": "Food ingestion provides relief of the symptoms", "options": {"A": "Non-bilious vomiting", "B": "Early satiety", "C": "Ibuprofen use", "D": "Omeprazole provides relief of the symptoms", "E": "Food ingestion provides relief of the symptoms"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 21-year-old man presents to a physician because of extreme fatigue, palpitations, fever, and weight loss. He developed these symptoms gradually over the past 3 months. His blood pressure is 110/80 mm Hg, heart rate is 109/min, respiratory rate is 17/min, and temperature is 38.1°C (100.6°F). The patient is emaciated and pale. There are conjunctival hemorrhages and several bruises noted in the inner cubital area bilaterally. There are also a few lesions on the left foot. The cardiac examination reveals a holosystolic murmur best heard at the 4th intercostal space at the left sternal edge. Two blood cultures grew Staphylococcus aureus, and echocardiography shows a tricuspid valve aneurysm. Which of the following would most likely be revealed in a detailed history from this patient?", "answer": "Chronic intravenous drug usage", "options": {"A": "Percutaneous nephrostomy for acute ureterolithiasis 5 months ago", "B": "Lung abscess evacuation 3 months ago", "C": "Catheterization of the urinary bladder", "D": "Chronic intravenous drug usage", "E": "Adenoidectomy 6 months ago"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-month-old boy of Ashkenazi-Jewish descent presents with loss of developmental milestones. On ocular exam, a cherry-red macular spot is observed. No hepatomegaly is observed on physical exam. Microscopic exam shows lysosomes with onion-skin appearance.\n\nWhat is the most likely underlying biochemical abnormality?", "answer": "Accumulation of GM2 ganglioside", "options": {"A": "Accumulation of ceramide trihexoside", "B": "Accumulation of galactocerebroside", "C": "Accumulation of sphingomyelin", "D": "Accumulation of GM2 ganglioside", "E": "Accumulation of glucocerebroside"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 21-year-old woman presents to her primary care doctor for an initial visit. She is a Syrian refugee and arrived in the United States 2 weeks ago. She has been living in refugee camps throughout Jordan and Turkey for the past 2 years. She has a 3-year-old son and reports that she has limited her food intake in order to ensure that her son has adequate nutrition. She reports decreased vision most noticeable over the past 6 months that is worse in low-light settings. She also reports severe dry eyes that have not improved with eye drops. She has no known past medical history and takes no medications. Her body mass index is 18.1 kg/m^2. On exam, she appears lethargic but is able to respond to questions appropriately. She has dry mucous membranes and decreased skin turgor. Her conjunctiva appears dry, thickened, and wrinkled. There is a small corneal ulcer on the lateral aspect of the left eye. This patient's symptoms are most consistent with a deficiency in a vitamin that contributes to which of the following processes?", "answer": "T-cell differentiation", "options": {"A": "Collagen synthesis", "B": "T-cell differentiation", "C": "Clotting factor synthesis", "D": "Cystathionine synthesis", "E": "Methylation reactions"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Three days after delivery, a 1100-g (2-lb 7-oz) newborn has a tonic seizure that lasts for 25 seconds. She has become increasingly lethargic over the past 18 hours. She was born at 31 weeks' gestation. Antenatal period was complicated by chorioamnionitis. Apgar scores were 3 and 6 at 1 and 5 minutes, respectively. She appears ill. Her pulse is 123/min, respirations are 50/min and irregular, and blood pressure is 60/30 mm Hg. Examination shows a tense anterior fontanelle. The pupils are equal and react sluggishly to light. Examination shows slow, conjugate back and forth movements of the eyes. Muscle tone is decreased in all extremities. The lungs are clear to auscultation. Which of the following is the most likely diagnosis?", "answer": "Intraventricular hemorrhage", "options": {"A": "Galactosemia", "B": "Spinal muscular atrophy", "C": "Phenylketonuria", "D": "Congenital hydrocephalus", "E": "Intraventricular hemorrhage"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A researcher is studying the ability of breast cancer cells to metastasize. Neoplastic cells obtained from 30 patients with stage IV ductal carcinoma of the breast are tagged with a fluorescent antibody. The cells are then inserted into a medium resembling normal human tissue. After 2 weeks, all samples show in vitro hematogenous invasion and migration away from the original site of insertion. Which of the following properties is most likely responsible for the ability of these neoplastic cells to metastasize?", "answer": "Release of matrix metalloproteinase", "options": {"A": "Loss of cellular polarity", "B": "Overexpression of HER2/neu", "C": "Increase in N:C ratio", "D": "Presence of fibrous tissue capsule", "E": "Release of matrix metalloproteinase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A newlywed couple comes to your office for genetic counseling. Both potential parents are known to be carriers of the same Cystic Fibrosis (CF) mutation. What is the probability that at least one of their next three children will have CF if they are all single births?", "answer": "37/64", "options": {"A": "0", "B": "1/64", "C": "27/64", "D": "37/64", "E": "1"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old woman makes an appointment at her physician’s office for a regular health check-up. She does not have any complaints and mentions that she has started to train for an upcoming marathon and hydrates exclusively with electrolyte solutions. She has been trying unsuccessfully to quit smoking for a few years now. She has hypercholesterolemia, which is controlled with a low-cholesterol diet. Family history is significant for hypertension in both of her parents. Her father died of myocardial infarction a few years ago. The vital signs include heart rate 55/min, respiratory rate 16/min, temperature 37.6 °C (99.68 °F), and blood pressure 120/88 mm Hg. The physical exam findings are within normal limits. A routine electrocardiogram (ECG) is done and is shown below. The abnormal wave seen on the ECG tracing represents which of the following mechanical events?", "answer": "Ventricular repolarization", "options": {"A": "Ventricular depolarization", "B": "Period between ventricular depolarization and repolarization", "C": "Ventricular repolarization", "D": "Atrial depolarization", "E": "Atrial repolarization"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old female presents to her primary care doctor for prenatal counseling before attempting to become pregnant for the first time. She is an avid runner, and the physician notes her BMI of 17.5. The patient complains of chronic fatigue, which she attributes to her busy lifestyle. The physician orders a complete blood count that reveals a Hgb 10.2 g/dL (normal 12.1 to 15.1 g/dL) with an MCV 102 µm^3 (normal 78 to 98 µm^3). A serum measurement of a catabolic derivative of methionine returns elevated. Which of the following complications is the patient at most risk for if she becomes pregnant?", "answer": "Placenta abruptio", "options": {"A": "Hyperemesis gravidarum", "B": "Gestational diabetes", "C": "Placenta previa", "D": "Placenta abruptio", "E": "Placenta accreta"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old girl is admitted to the emergency department with severe retrosternal chest pain. The pain began suddenly after an episode of self-induced vomiting following a large meal. The patient’s parents say that she is very restricted in the foods she eats and induces vomiting frequently after meals. Vital signs are as follows: blood pressure 100/60 mm Hg, heart rate 98/min, respiratory rate 14/min, and temperature 37.9℃ (100.2℉). The patient is pale and in severe distress. Lungs are clear to auscultation. On cardiac examination, a crunching, raspy sound is auscultated over the precordium that is synchronous with the heartbeat. The abdomen is soft and nontender. Which of the following tests would most likely confirm the diagnosis in this patient?", "answer": "Contrast esophagram", "options": {"A": "Upper endoscopy", "B": "ECG", "C": "Echocardiography", "D": "Contrast esophagram", "E": "Measurement of D-dimer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 47-year-old woman comes to the physician for a 2-month history of fatigue, intermittent left-sided flank pain, and diffuse extremity pain. She was treated for a prolactinoma 5 years ago and has had recurrent antral and duodenal peptic ulcers despite medical therapy. Her only medication is omeprazole. Physical examination shows a moderately distended abdomen that is diffusely tender to palpation. There is mild left-sided costovertebral angle tenderness. Serum studies show a calcium of 12 mg/dL, phosphorus of 2 mg/dL, and parathyroid hormone level of 826 pg/mL. An ultrasound of the abdomen shows multiple kidney stones in the left ureteropelvic junction. This patient is most likely to have which of the following protein abnormalities?", "answer": "Altered menin protein", "options": {"A": "Inactivation of RET proto-oncogene", "B": "Altered merlin protein expression", "C": "Altered menin protein", "D": "Mutation of VHL tumor suppressor", "E": "Mutation in C-Kit protein"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman comes to the physician with a history of bright red blood in her stools for 3 days. She has defecated once per day. She does not have fever, pain on defecation, or abdominal pain. She was treated for a urinary tract infection with levofloxacin around 3 months ago. Menses occur at regular intervals of 28–30 days and lasts 3–4 days. Her father died of colon cancer 4 years ago. Her only medication is an iron supplement. She is 162 cm (5 ft 4 in) tall and weighs 101.2 kg (223 lbs); BMI is 38.3 kg/m2. Her temperature is 36.5°C (97.7°F), pulse is 89/min, and blood pressure is 130/80 mm Hg. Rectal examination shows anal skin tags. Anoscopy shows multiple enlarged bluish veins above the dentate line at 7 and 11 o'clock positions. When asked to exhale through a closed nostril a mass prolapses but spontaneously reduces when breathing normally. Which of the following is the most appropriate next step in management?", "answer": "Docusate therapy", "options": {"A": "Docusate therapy", "B": "Topical diltiazem", "C": "Propranolol therapy", "D": "Infrared coagulation", "E": "Hemorrhoidectomy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 73-year-old female with no past medical history is hospitalized after she develops a fever associated with increasing shortness of breath. She states that 1 week prior, she had a cold which seemed to be resolving. Yesterday, however, she noticed that she started to feel feverish, measured her temperature to be 101.5°F (38.6°C), and also developed an unproductive dry cough and difficulty breathing. On exam, her temperature is 100.8°F (38.2°C), blood pressure is 110/72 mmHg, pulse is 96/min, and respirations are 16/min. Her exam demonstrates decreased breath sounds at the right lung base. The chest radiograph shows a right-sided pleural effusion with an opacity in the right lower lobe that is thought to be a bacterial pneumonia. Which of the following can be expected on a sample of the effusion fluid?", "answer": "Protein-rich fluid", "options": {"A": "Clear fluid", "B": "Hypocellular fluid", "C": "Malignant cells", "D": "Protein-rich fluid", "E": "Specific gravity of 1.010"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old man comes to the physician because of burning pain in his neck and arms for a year. He has also had paresthesias in his hands during this period. He has had increasing weakness in both hands during the past 3 months. He has type 2 diabetes mellitus, hypercholesterolemia, and hypertension. He was involved in a motor vehicle collision 3 years ago. Current medications include metformin, sitagliptin, enalapril, atorvastatin, and aspirin. He has had 7 sexual partners in his lifetime; he uses condoms inconsistently. He is oriented to time, place, and person. Vital signs are within normal limits. The pupils are equal and reactive to light. Examination of the upper extremities shows decreased muscle strength, absent reflexes, and decreased hand grip with fasciculations bilaterally. Sensation to temperature and pain is absent over the chest and bilateral upper arms. Vibration and joint position sensations are present in the upper limbs. Cranial nerve examination shows no focal findings. Examination of the lower extremities show no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Syringomyelia", "options": {"A": "Tabes dorsalis", "B": "Cervical disk prolapse", "C": "Brown-Séquard syndrome", "D": "Multiple sclerosis", "E": "Syringomyelia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old woman comes to the physician for evaluation of nausea and fatigue. Her last menstrual period was 8 weeks ago. She has a history of bipolar disorder controlled by a drug known to sometimes cause hypothyroidism and nephrogenic diabetes insipidus. She does not smoke cigarettes or drink alcohol. A urine pregnancy test is positive. An ultrasound of the pelvis shows a viable intrauterine pregnancy. The fetus is most likely at increased risk for which of the following anomalies?", "answer": "Atrialization of the right ventricle", "options": {"A": "Abnormal placentation", "B": "Aplasia cutis", "C": "Atrialization of the right ventricle", "D": "Neural tube defects", "E": "Hypoplastic or absent limbs"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old woman is brought to the emergency department after briefly losing consciousness while walking her dog. She spontaneously regained consciousness 20 seconds later. She has a history of atrial fibrillation. Current medications include metoprolol. She reports that she forgot to take her medication the day before and took double the dose this morning instead. A decrease in which of the following most likely contributed to this patient's episode?", "answer": "Activity of adenylyl cyclase in cardiomyocytes", "options": {"A": "Phosphorylation of myosin light chains in vascular smooth muscle cells", "B": "Activity of protein kinase C in cardiomyocytes", "C": "Activity of protein kinase A in vascular smooth muscle cells", "D": "Activity of adenylyl cyclase in cardiomyocytes", "E": "Diastolic efflux of calcium in cardiomyocytes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man is witnessed falling off his bicycle. The patient rode his bicycle into a curb and hit his face against a rail. The patient did not lose consciousness and is ambulatory at the scene. There is blood in the patient's mouth and one of the patient's teeth is found on the sidewalk. The patient is transferred to the local emergency department. Which of the following is the best method to transport this patient's tooth?", "answer": "Submerged in milk", "options": {"A": "Submerged in milk", "B": "Submerged in normal saline", "C": "Submerged in water", "D": "Wrapped in sterile gauze", "E": "Wrapped in gauze soaked in normal saline"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old man presents to his primary care physician because of abdominal pain that started after he went camping several months ago and drank from a mountain stream. This past year, he also went on a trip around the world, eating local foods at each stop. Furthermore, he has had a history of cholelithiasis and had his gallbladder removed 3 years ago. Otherwise, his medical history is significant for well-controlled hypertension and diabetes. Based on clinical suspicion, an endoscopy and biopsy was performed showing a mix of mononuclear cells and a motile, urease-positive, oxidase-positive, spiral shaped organism. The changes seen on biopsy in this patient most likely predispose him to which of the following pathologies?", "answer": "MALT lymphoma", "options": {"A": "Esophageal adenocarcinoma", "B": "Gallbladder adenocarcinoma", "C": "Colon adenocarcinoma", "D": "MALT lymphoma", "E": "Pancreatic adenocarcinoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 46-year-old man comes to the physician because of a 1-week history of headache, muscle pain, and recurrent fever spikes that occur without a noticeable rhythm. Two weeks ago, he returned from a 5-week-long world trip during which he climbed several mountains in India, Africa, and Appalachia. Chemoprophylaxis with chloroquine was initiated one week prior to the trip. Physical examination shows jaundice. The spleen is palpated 2 cm below the left costal margin. His hemoglobin concentration is 10 g/dL. A photomicrograph of a peripheral blood smear is shown. Which of the following agents is the most likely cause of this patient's findings?", "answer": "Plasmodium falciparum", "options": {"A": "Trypanosoma cruzi", "B": "Plasmodium falciparum", "C": "Chikungunya virus", "D": "Trypanosoma brucei", "E": "Leishmania donovani"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old woman comes to the emergency department because of progressive numbness and weakness in her left arm and left leg for 2 days. During this period, she has also had urinary urgency and incontinence. Three months ago, she had blurry vision, difficulty distinguishing colors, and headache for one week, all of which have resolved. The patient has smoked a half pack of cigarettes daily for 10 years and drinks four glasses of wine each week. Her temperature is 37°C (98.6°F), pulse is 78/min, respirations are 14/min, and blood pressure is 110/68 mm Hg. Examination shows 3/5 strength in the left arm and leg, and 5/5 strength on the right side. Upon flexion of the neck, the patient experiences a shooting electric sensation that travels down the spine. MRI of the brain shows gadolinium-enhancing lesions in the right central sulcus, cervical spinal cord, and optic nerve. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Administer IV methylprednisolone", "options": {"A": "Administer lorazepam", "B": "Administer IV methylprednisolone", "C": "Plasmapheresis", "D": "Administer tissue plasminogen activator", "E": "Glatiramer acetate therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old woman comes to the emergency department because of upper abdominal pain and nausea for the past hour. The patient rates the pain as an 8 to 9 on a 10-point scale. She has had an episode of nonbloody vomiting since the pain started. She has a history of type 2 diabetes mellitus, hypertension, and osteoporosis. The patient has smoked 2 packs of cigarettes daily for 40 years. She drinks 5–6 alcoholic beverages daily. Current medications include glyburide, lisinopril, and oral vitamin D supplements. Her temperature is 38.5°C (101.3°F), pulse is 110/min, and blood pressure is 138/86 mm Hg. Examination shows severe epigastric tenderness to palpation with guarding but no rebound. Ultrasonography of the abdomen shows diffuse enlargement of the pancreas; no gallstones are visualized. The patient is admitted to the hospital for pain control and intravenous hydration. Which of the following is the most appropriate next step in the management of this patient’s pain?", "answer": "Patient-controlled intravenous hydromorphone", "options": {"A": "Patient-controlled intravenous hydromorphone", "B": "Transdermal bupivacaine on request", "C": "Oral acetaminophen every 6 hours", "D": "Oral gabapentin every 24 hours", "E": "Transdermal fentanyl every 72 hours"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "The patient undergoes a mammogram, which shows a 6.5mm sized mass with an irregular border and spiculated margins. A subsequent core needle biopsy of the mass shows infiltrating ductal carcinoma with HER2-positive, estrogen-negative, and progesterone-negative immunohistochemistry staining. Blood counts and liver function tests are normal. Laboratory studies show:\nHemoglobin 12.5 g/dL\nSerum\nNa+ 140 mEq/L\nCl- 103 mEq/L\nK+ 4.2 mEq/L\nHCO3- 26 mEq/L\nCa2+ 8.9 mg/dL\nUrea Nitrogen 12 mg/dL\nGlucose 110 mg/dL\nAlkaline Phosphatase 25 U/L\nAlanine aminotransferase (ALT) 15 U/L\nAspartate aminotransferase (AST) 13 U/L\nWhich of the following is the most appropriate next step in management?\"", "answer": "Breast-conserving therapy and sentinel lymph node biopsy", "options": {"A": "Breast-conserving therapy and sentinel lymph node biopsy", "B": "Trastuzumab therapy", "C": "Whole-body PET/CT", "D": "Bilateral mastectomy with lymph node dissection", "E": "Bone scan"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A recent study examined trends in incidence and fatality of ischemic stroke in a representative sample of Scandinavian towns. The annual incidence of ischemic stroke was calculated to be 60 per 2,000 people. The 1-year case fatality rate for ischemic stroke was found to be 20%. The health department of a town in southern Sweden with a population of 20,000 is interested in knowing the 1-year mortality conferred by ischemic stroke. Based on the study's findings, which of the following estimates the annual mortality rate for ischemic stroke per 20,000?", "answer": "120 people", "options": {"A": "12 people", "B": "120 people", "C": "400 people", "D": "60 people", "E": "600 people"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An infectious disease chairperson of a large hospital determines that the incidence of Clostridioides difficile infections at the hospital is too high. She proposes an initiative to restrict the usage of clindamycin in the hospital to determine if that lowers the incidence of C. difficile infections. She puts in place a requirement that an infectious disease fellow needs to approve any prescription of clindamycin. After 2 months, she reviews the hospital infection data and determines that the incidence of C. difficile infections has decreased, but not to the extent that she had hoped. Consequently, she decides to include fluoroquinolone antibiotics in the antibiotic restriction and examine the data again in another 2 months. Which of the following best describes the process being used by the infectious disease chairperson?", "answer": "Plan, do, study, act cycle", "options": {"A": "High reliability organization", "B": "Root cause analysis", "C": "Failure mode and effects analysis", "D": "Plan, do, study, act cycle", "E": "Lean process improvement"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old man with coronary artery disease comes to the physician because of intermittent episodes of substernal chest pain and shortness of breath. The episodes occur only when walking up stairs and resolves after resting for a few minutes. He is a delivery man and is concerned because the chest pain has impacted his ability to work. His pulse is 98/min and blood pressure is 132/77 mm Hg. Physical examination is unremarkable. An ECG shows no abnormalities. A drug that blocks which of the following receptors is most likely to prevent future episodes of chest pain from occurring?", "answer": "Beta-1 adrenergic receptors", "options": {"A": "Alpha-2 adrenergic receptors", "B": "Angiotensin II receptors", "C": "Aldosterone receptors", "D": "M2 muscarinic receptors", "E": "Beta-1 adrenergic receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 3-month-old girl is brought to the physician because of fever, irritability, and rash for 3 days. The rash started around the mouth before spreading to the trunk and extremities. Her temperature is 38.6°C (101.5°F). Examination shows a diffuse erythematous rash with flaccid bullae on the neck, flexural creases, and buttocks. Gentle pressure across the trunk with a gloved finger creates a blister. Oropharyngeal examination shows no abnormalities. Which of the following is the most likely underlying mechanism of these skin findings?", "answer": "Toxin-induced cleavage of desmoglein", "options": {"A": "Toxin-induced cleavage of desmoglein", "B": "Bacterial production of erythrogenic toxin", "C": "Bacterial invasion of the epidermis", "D": "Autoantibody deposition in stratum spinosum", "E": "Autoantibody binding of hemidesmosomes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old man comes to the physician for a follow-up examination. Four days ago, he injured his right knee while playing soccer. Increased laxity of the right knee joint is noted when the knee is flexed to 30° and an abducting force is applied to the lower leg. The examination finding in this patient is most likely caused by damage to which of the following structures?", "answer": "Medial collateral ligament", "options": {"A": "Posterior cruciate ligament", "B": "Lateral collateral ligament", "C": "Lateral meniscus", "D": "Medial collateral ligament", "E": "Anterior cruciate ligament"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 63-year-old woman presents to her primary care doctor with increased urinary frequency. She has noticed that over the past 6 months, she has had to urinate more often than usual. Several times per day, she develops a rapid-onset need to urinate and has occasionally been unable to reach the restroom. These symptoms have caused her a lot of distress and impacted her work as a grocery store clerk. She has tried pelvic floor exercises, decreasing her caffeine consumption, and has intentionally lost 20 pounds in an effort to alleviate her symptoms. She denies urinary hesitancy or hematuria. Her past medical history is notable for rheumatoid arthritis for which she takes methotrexate. She does not smoke or drink alcohol. Her temperature is 98.8°F (37.1°C), blood pressure is 124/68 mmHg, pulse is 89/min, and respirations are 19/min. She is well-appearing and in no acute distress. Which of the following interventions would be most appropriate in this patient?", "answer": "Oxybutynin", "options": {"A": "Intermittent catheterization", "B": "Oxybutynin", "C": "Pessary placement", "D": "Tamsulosin", "E": "Topical estrogen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old man presents to the behavioral health clinic for an evaluation after seeing animal-shaped clouds in the form of dogs, cats, and monkeys. The patient says that these symptoms have been present for more than 2 weeks. Past medical history is significant for simple partial seizures for which he takes valproate, but he has not had his medication adjusted in several years. His vital signs include: blood pressure of 124/76 mm Hg, heart rate of 98/min, respiratory rate of 12/min, and temperature of 37.1°C (98.8°F). On physical examination, the patient is alert and oriented to person, time, and place. Affect is not constricted or flat. Speech is of rapid rate and high volume. Pupils are equal and reactive bilaterally. The results of a urine drug screen are as follows:\nAlcohol positive\nAmphetamine negative\nBenzodiazepine negative\nCocaine positive\nGHB negative\nKetamine negative\nLSD negative\nMarijuana negative\nOpioids negative\nPCP negative\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Illusion", "options": {"A": "Cocaine intoxication", "B": "Illusion", "C": "Visual hallucination", "D": "Delusion", "E": "Alcohol withdrawal"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man presents to his primary care physician with a 1 week history of persistent dry cough and worsening shortness of breath. He says that he has also been experiencing some abdominal pain and weakness. He has never experienced these symptoms before. His past medical history is significant for persistent ventricular tachycardia, and he started a new medication to control this arrhythmia about 1 month prior to presentation. Chest radiograph reveals patchy opacification bilaterally, and computed tomography (CT) scan shows diffuse ground glass changes. The drug that is most likely responsible for this patient's symptoms has which of the following mechanisms of action?", "answer": "Potassium channel blocker", "options": {"A": "Beta-adrenergic blocker", "B": "Calcium channel blocker", "C": "Potassium channel blocker", "D": "Sodium channel blocker with prolonged refractory period", "E": "Sodium channel blocker with shortened refractory period"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3-year-old boy is brought to the emergency room by his mother with fever and difficulty breathing after receiving the BCG vaccine. He has never had a reaction to a vaccine before. He has a history of 2 salmonella infections over the past 2 years. He was born at 35 weeks’ gestation and spent one day in the neonatal intensive care unit. His parents' family histories are unremarkable. His temperature is 101°F (38.3°C), blood pressure is 80/55 mmHg, pulse is 135/min, and respirations are 24/min. On examination, he appears acutely ill. He has increased work of breathing with intercostal retractions. A petechial rash is noted on his trunk and extremities. A serological analysis in this patient would most likely reveal decreased levels of which of the following cytokines?", "answer": "Interferon gamma", "options": {"A": "Interferon alpha", "B": "Interferon gamma", "C": "Interleukin 1", "D": "Interleukin 12", "E": "Tumor necrosis factor alpha"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old woman with metastatic breast cancer comes to the physician for a follow-up examination. She had a mastectomy 6 months ago and received chemotherapy with doxorubicin and paclitaxel. A CT scan of the chest shows new metastases in the lungs and liver. Adjuvant therapy is initiated with a drug that inhibits the formation of deoxythymidine monophosphate and results in the accumulation of deoxyuridine triphosphate. The patient is advised to avoid folic acid supplementation while receiving this drug in order to prevent the toxic effects of this drug. Which of the following drugs was most likely given?", "answer": "Capecitabine", "options": {"A": "Hydroxyurea", "B": "Leflunomide", "C": "Azathioprine", "D": "Mycophenolate mofetil", "E": "Capecitabine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-year-old boy with a history of cerebral palsy is brought to the neurology clinic by his mother with progressive tightness in the lower extremities. Although the patient has been intermittently undergoing physiotherapy for the past 2 years at a specialized center, the patient’s mother is concerned he cannot yet climb the stairs. The neurologist recommends a different treatment, which involves multiple intramuscular injections of a drug in the muscles of the lower extremities to relieve tightness. The neurologist says this treatment approach is also often used to relieve headaches and reduce facial wrinkles. Which of the following is most likely the mechanism of action of this drug?", "answer": "Blocks the release of acetylcholine", "options": {"A": "Acts as a superantigen", "B": "Stimulates adenylate cyclase", "C": "Reduces neurotransmitter GABA", "D": "Blocks the release of acetylcholine", "E": "Interferes with the 60s ribosomal subunit"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old woman, gravida 3, para 2, at 32 weeks' gestation comes to the physician for a follow-up examination 2 days after an increased blood pressure measurement. She now reports having a headache and visual disturbances for the past 12 hours. Her only medication is a prenatal vitamin. Her temperature is 36.7°C (98.1°F), pulse is 90/min, and blood pressure is 164/80 mm Hg. Her blood pressure at her first-trimester prenatal visit was 110/70 mm Hg. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12.5 g/dL\nPlatelet count 285,000/mm3\nSerum\nCreatinine 1.0 mg/dL\nUrine\nBlood negative\nProtein negative\nWhich of the following is the most likely primary component in the pathogenesis of this patient's condition?\"", "answer": "Abnormal remodeling of spiral arteries", "options": {"A": "Vasogenic cerebral edema", "B": "Increase in circulating plasma volume", "C": "Hyperperfusion of placental tissue", "D": "Abnormal remodeling of spiral arteries", "E": "Overactivation of the coagulation cascade"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Five days after being admitted to the hospital for a scald wound, a 2-year-old boy is found to have a temperature of 40.2°C (104.4°F). He does not have difficulty breathing, cough, or painful urination. He initially presented one hour after spilling a pot of boiling water on his torso while his mother was cooking dinner. He was admitted for fluid resuscitation, nutritional support, pain management, and wound care, and he was progressing well until today. He has no other medical conditions. Other than analgesia during this hospital stay, he does not take any medications. He appears uncomfortable but not in acute distress. His pulse is 150/min, respirations are 41/min, and blood pressure is 90/50 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 99%. Examination shows uneven, asymmetrical scalding covering his anterior torso in arrow-like patterns with surrounding erythema and purulent discharge. The remainder of the examination shows no abnormalities. His hemoglobin is 13.4 g/dL, platelet count is 200,000/mm3, and leukocyte count is 13,900/mm3. Which of the following is the most appropriate initial pharmacological treatment for this patient?", "answer": "Vancomycin and cefepime", "options": {"A": "Amoxicillin/clavulanic acid and ceftriaxone", "B": "Ampicillin/sulbactam and daptomycin", "C": "Piperacillin/tazobactam and cefepime", "D": "Vancomycin and metronidazole", "E": "Vancomycin and cefepime"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old man comes to the physician because of severe burning with urination for the past 3 days. During this period, he has had clear urethral discharge early in the morning. He has no history of serious illness, except for a rash following treatment with erythromycin 20 years ago. The patient takes no medications. He is sexually active with one male and one female partner; they use condoms inconsistently. His younger brother was diagnosed with Crohn disease at the age of 24 years. The patient does not smoke. He drinks one to two beers on weekends. He appears well. Temperature is 36.8°C (98°F), pulse is 75/min, and blood pressure is 135/78 mm Hg. Physical examination shows no abnormalities. Gram stain of a urethral swab shows neutrophils but no organisms. Which of the following is the most likely causal pathogen?", "answer": "Chlamydia trachomatis", "options": {"A": "Neisseria gonorrhoeae", "B": "Adenovirus", "C": "Trichomonas vaginalis", "D": "Chlamydia trachomatis", "E": "Herpes simplex virus\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man presents to the emergency department with confusion. The patient’s wife states that her husband has become more somnolent over the past several days and now is very confused. The patient has no complaints himself, but is answering questions inappropriately. The patient has a past medical history of diabetes and hypertension. His temperature is 98.3°F (36.8°C), blood pressure is 127/85 mmHg, pulse is 138/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is notable for a confused man with dry mucous membranes. Initial laboratory studies are ordered as seen below.\n\nSerum:\nNa+: 135 mEq/L\nCl-: 100 mEq/L\nK+: 3.0 mEq/L\nHCO3-: 23 mEq/L\nBUN: 30 mg/dL\nGlucose: 1,299 mg/dL\nCreatinine: 1.5 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the most appropriate initial treatment for this patient?", "answer": "Normal saline and potassium", "options": {"A": "Insulin", "B": "Insulin and normal saline", "C": "Insulin and potassium", "D": "Insulin, normal saline, and potassium", "E": "Normal saline and potassium"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old woman presents to her gynecologist complaining of mild pelvic discomfort and a frothy, yellowish discharge from her vagina for the past 2 weeks. She also complains of pain during sexual intercourse and sometimes after urination. Her past medical history is noncontributory. She takes oral contraceptives and a multivitamin daily. She has had two male sexual partners in her lifetime and uses condoms inconsistently. Today, her vitals are normal. On pelvic exam, she has vulvovaginal erythema and a 'strawberry cervix' that is tender to motion, with minimal green-yellow malodorous discharge. A swab of the vaginal wall is analyzed for pH at bedside. Vaginal pH is 5.8. Which of the following is the most likely diagnosis for this patient?", "answer": "Trichomoniasis", "options": {"A": "Vulvovaginal candidiasis", "B": "Atrophic vaginitis", "C": "Bacterial vaginosis", "D": "Chlamydia", "E": "Trichomoniasis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old African American man is brought to the emergency department by police. The patient refused to leave a petting zoo after closing. He states that he has unique ideas to revolutionize the petting zoo experience. The patient has a past medical history of multiple suicide attempts. His temperature is 99.5°F (37.5°C), blood pressure is 130/85 mmHg, pulse is 100/min, respirations are 16/min, and oxygen saturation is 99% on room air. The patient's cardiac and pulmonary exams are within normal limits. He denies any nausea, vomiting, shortness of breath, or systemic symptoms. The patient struggles to answer questions, as he is constantly changing the subject and speaking at a very rapid rate. The patient is kept in the emergency department overnight and is observed to not sleep and is very talkative with the nurses. Which of the following is the best long-term therapy for this patient?", "answer": "Lithium", "options": {"A": "Lithium", "B": "Valproic acid", "C": "Risperidone", "D": "Haloperidol", "E": "Diphenhydramine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man presents for physical and preventive health screening, specifically for prostate cancer. He has not been to the doctor in a long time. Past medical history is significant for hypertension that is well-managed. Current medication is hydrochlorothiazide. He has one uncle who died of prostate cancer. He drinks one or two alcoholic drinks on the weekends and does not smoke. Today his temperature is 37.0°C (98.6°F), blood pressure is 125/75 mm Hg, pulse is 82/min, respiratory rate is 15/min, and oxygen saturation is 99% on room air. There are no significant findings on physical examination. Which of the following would be the most appropriate recommendation for prostate cancer screening in this patient?", "answer": "Serum PSA level", "options": {"A": "No screening indicated at this time", "B": "Digital rectal examination", "C": "Serum PSA level", "D": "Transrectal ultrasound (TRUS)", "E": "Contrast CT of the abdomen and pelvis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 3-year-old male is evaluated for frequent nose bleeds. Physical examination shows diffuse petechiae on the patient’s distal extremities. Peripheral blood smear shows an absence of platelet clumping. An ELISA binding assay reveals that platelet surfaces are deficient in GpIIb/IIIa receptors. Which of the following anticoagulants pharmacologically mimics this condition?", "answer": "Abciximab", "options": {"A": "Abciximab", "B": "Aspirin", "C": "Warfarin", "D": "Clopidogrel", "E": "Cilostazol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 23-year-old man complains of lower back pain that began approximately 6 months ago. He is unsure why he is experiencing this pain and notices that this pain is worse in the morning after waking up and improves with physical activity. Ibuprofen provides significant relief. He denies bowel and bladder incontinence or erectile dysfunction. Physical exam is notable for decreased chest expansion, decreased spinal range of motion, 5/5 strength in both lower extremities, 2+ patellar reflexes bilaterally, and an absence of saddle anesthesia. Which of the following is the most appropriate next test for this patient?", "answer": "Radiograph sacroiliac joint", "options": {"A": "ESR", "B": "HLA-B27", "C": "MRI sacroiliac joint", "D": "Radiograph sacroiliac joint", "E": "Slit-lamp examination"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A genetic population study is being conducted to find the penetrance of a certain disease. This disease is associated with impaired iron metabolism and primarily affects the liver. Patients often present with diabetes and bronze skin pigmentation. After a genetic screening of 120 inhabitants with a family history of this disease, 40 were found to have the disease-producing genotype, but only 10 presented with symptoms. What are the chances of the screened patients with said genotype developing the disease phenotype?\n ", "answer": "25%", "options": {"A": "3%", "B": "25%", "C": "4%", "D": "40%", "E": "0.4%"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 9-year-old, Caucasian girl presents to your office with severe abdominal pain. Her mother also mentions that she has been urinating significantly less lately. History from the mother reveals that the girl suffers from acne vulgaris, mild scoliosis, and had a bout of diarrhea 3 days ago after a family barbecue. Lab work is done and is notable for a platelet count of 97,000 with a normal PT and PTT. The young girl appears dehydrated, yet her serum electrolyte levels are normal. What is the most likely etiology of this girl's urinary symptoms?", "answer": "Shiga-like toxin production from EHEC", "options": {"A": "Hypothalamic dysfucntion", "B": "Surreptitious laxative use", "C": "Toxic shock syndrome", "D": "Shiga toxin production from Shigella", "E": "Shiga-like toxin production from EHEC"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old male presents to his primary care physician with right upper quadrant pain that has progressed over the last three months with unexplained weakness and joint pains that have been \"out of the ordinary\" over the last year. On history, you note the patient lives a sedentary lifestyle, rarely leaves the house, has controlled diabetes diagnosed 15 years ago, and has documented cardiomyopathy. On physical exam the man appears non-toxic, sclera are icteric, cornea appear normal, generalized pain is elicited on palpation of the right upper quadrant, and skin appears quite bronzed on his extremities. What is this patient most at risk for ten to fifteen years later due to his underlying condition?", "answer": "Hepatocellular carcinoma", "options": {"A": "Colonic adenocarcinoma", "B": "Pulmonary fibrosis", "C": "Prostatic adenocarcinoma", "D": "Hepatocellular carcinoma", "E": "Movement disorders"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 6-month-old girl has a weak cry, poor suck, ptosis, and constipation. Her condition began 2 days ago with a single episode of abundant watery stool and elevated temperature. The child was born at term to a healthy 26-year-old mother with an uneventful antenatal course and puerperium. The infant was exclusively breastfed till 5 months of age, after which she began receiving grated potatoes, pumpkin, carrots, and apples, in addition to the breastfeeding. She does not receive any fluids other than breast milk. The last new food item to be introduced was homemade honey that her mother added several times to grated sour apples as a sweetener 2 weeks before the onset of symptoms. The vital signs are as follows: blood pressure 70/40 mm Hg, heart rate 98/min, respiratory rate 29/min, and temperature 36.4°C (98.2°F). On physical examination, she is lethargic and has poor head control. A neurologic examination reveals ptosis and facial muscle weakness, widespread hypotonia, and symmetrically decreased upper and lower extremity reflexes. Which of the following options is a part of the pathogenesis underlying the patient’s condition?", "answer": "Vegetative form of Clostridium botulinum spores in the patient's colon", "options": {"A": "Hypocalcemia due to a decrease in breast milk consumption", "B": "Hyperkalemia due to increased dietary intake", "C": "Vegetative form of Clostridium botulinum spores in the patient's colon", "D": "Dehydration due to the absence of additional fluid intake", "E": "Development of antibodies against the acetylcholine receptor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 16-year-old male comes to his doctor worried that he has not yet gone through puberty. He feels that his genitals are less developed than they should be for his age. On physical exam, you note an absence of facial hair and that his voice has not yet deepened. Your exam confirms that he is Tanner Stage 1. On a thorough review of systems, you learn that the patient has lacked a sense of smell from birth. Which of the following is implicated in the development of this patient's underlying condition?", "answer": "Failure of normal neuronal migration during development", "options": {"A": "Chromosomal duplication", "B": "Expansile suprasellar tumor", "C": "Exposure to radiation", "D": "Failure of normal neuronal migration during development", "E": "Defect in steroid production"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old woman presents to a physician with weakness and fatigue for a week. She mentions that she has been taking oral fluconazole for the last 4 weeks for the treatment of tinea capitis. She also says that she loves coffee and usually consumes 4–6 cups of coffee every day. On physical examination, her vital signs are stable and examination of all systems, including nervous system, is normal. Her laboratory evaluation reveals that her serum potassium level is 3.1 mmol/L (3.1 mEq/L). The physician orders an ECG. Which of the following findings is most likely to be present?", "answer": "Depression of ST segment", "options": {"A": "Widening of QRS complexes", "B": "Tall peaked T waves", "C": "Disappearing P waves", "D": "Depression of ST segment", "E": "Shortened QT interval"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-month-old girl is brought to the physician because she has been regurgitating and vomiting 10–15 minutes after feeding for the past 3 weeks. She is breastfed and formula-fed. She was born at 38 weeks' gestation and weighed 2966 g (6 lb 9 oz). She currently weighs 5878 g (12 lb 15 oz). She appears healthy. Vital signs are within normal limits. Examination shows a soft and nontender abdomen and no organomegaly. Which of the following is the most appropriate next best step in management?", "answer": "Positioning therapy", "options": {"A": "Esophageal pH monitoring", "B": "Upper endoscopy", "C": "Ultrasound of the abdomen", "D": "Pantoprazole therapy", "E": "Positioning therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 44-year-old man presents to his primary care physician due to a tremor. His tremor has been progressively worsening over the course of several weeks and he feels embarrassed and anxious about going to social events. He says these movements are involuntary and denies having an urge to have these movements. Medical history is significant for depression which is being treated with escitalopram. His mother is currently alive and healthy but his father committed suicide and had a history of depression. Physical examination is remarkable for impaired saccade initiation and brief, abrupt, and non-stereotyped movements involved the right arm. He also has irregular finger tapping. Which of the following is the best treatment for this patient's symptoms?", "answer": "Deutetrabenazine", "options": {"A": "Carbidopa-levodopa", "B": "Cognitive behavioral therapy", "C": "Deutetrabenazine", "D": "Switch to sertraline", "E": "Valproic acid"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the emergency department by ambulance following a motor vehicle accident. He was a restrained passenger. At the hospital, he is bleeding heavily from a large wound in his left leg. A review of medical records reveals a history of atrial fibrillation for which he takes warfarin. His international normalized ratio (INR) 2 days ago was 2.6. On physical exam he is cool and clammy. The vital signs include: heart rate 130/min and blood pressure 96/54 mm Hg. Aggressive resuscitation with intravenous normal saline is begun. Which of the following is the next best step to correct this patient's underlying coagulopathy?", "answer": "Give fresh frozen plasma (FFP)", "options": {"A": "Give cryoprecipitate", "B": "Give fresh frozen plasma (FFP)", "C": "Give intravenous vitamin K", "D": "Give packed red blood cells", "E": "Give platelets"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman comes to the physician because of worsening fatigue and shortness of breath. Her symptoms began 8 months ago and have progressively worsened since then. She had recurrent episodes of joint pain and fever during childhood. She does not smoke or drink alcohol. She emigrated from the Congo with her parents when she was 12 years old. Her temperature is 37.4°C (99.3°F), pulse is 90/min and regular, respirations are 18/min, and blood pressure is 140/90 mm Hg. There is an opening snap followed by a diastolic murmur at the fifth left intercostal space in the midclavicular line. If left untreated, this patient is at greatest risk for which of the following complications?", "answer": "Esophageal compression", "options": {"A": "Nephritic syndrome", "B": "Esophageal compression", "C": "Bleeding from intestinal angiodysplasia", "D": "Left ventricular hypertrophy", "E": "Ventricular tachycardia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-day-old boy is evaluated in the newborn nursery after the nurse witnessed the child convulsing. The child was born at 39 weeks gestation to a healthy 32-year-old G1P0 woman. Initial examination after birth was notable for a cleft palate. The child’s temperature is 99°F (37.2°C), blood pressure is 100/60 mmHg, pulse is 115/min, and respirations are 18/min. On exam, he appears somnolent. His face demonstrates periorbital fullness, hypoplastic nares, and small dysmorphic ears. A series of labs are drawn and shown below:\n\nHemoglobin: 13.1 g/dL\nHematocrit: 40%\nLeukocyte count: 4,000/mm^3 with normal differential\nPlatelet count: 200,000/mm^3\n\nSerum:\nNa+: 140 mEq/L\nCl-: 100 mEq/L\nK+: 3.8 mEq/L\nHCO3-: 25 mEq/L\nBUN: 19 mg/dL\nGlucose: 110 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 7.9 mg/dL\nPhosphate: 4.7 mg/dL\n\nThis patient is deficient in a hormone that has which of the following functions?", "answer": "Activates 1-alpha-hydroxylase", "options": {"A": "Activates 1-alpha-hydroxylase", "B": "Activates 24-alpha-hydroxylase", "C": "Activates 25-alpha-hydroxylase", "D": "Inhibits 1-alpha-hydroxylase", "E": "Inhibits 25-alpha-hydroxylase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old female with chronic renal failure presents with recent onset of bone pain. Serum analysis reveals decreased levels of calcium and elevated levels of parathyroid hormone. One of the mechanisms driving the elevated PTH is most similar to that seen in:", "answer": "End stage liver failure", "options": {"A": "End stage liver failure", "B": "Insufficient Ca intake", "C": "Parathyroid adenoma", "D": "Decreased functioning of the calcium-sensing receptor (CASR)", "E": "Sarcoidosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 41-year-old woman with subclinical hypothyroidism comes to the physician because of a 6-month history of progressively worsening headaches and irregular menses. Her menses had previously occurred at regular 30-day intervals with moderate flow, but her last menstrual period was 12 weeks ago. She also reports that her interest in sexual intercourse has recently decreased. Her serum prolactin level is elevated. Which of the following is the most appropriate pharmacotherapy for this patient?", "answer": "Bromocriptine", "options": {"A": "Bromocriptine", "B": "Estrogen", "C": "Methyldopa", "D": "Metoclopromide", "E": "L-thyroxine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old boy presents to the office with allergic rhinitis. He reports symptoms of sneezing, nasal congestion, itching, and postnasal drainage every September at the start of the school year. He has a family history of childhood asthma and eczema. He has not tried any medications for his allergies. Which of the following medications is the most appropriate next step to manage the patient's symptoms?", "answer": "Intranasal corticosteroids", "options": {"A": "Intranasal antihistamines", "B": "Intranasal cromolyn sodium", "C": "Intranasal decongestants", "D": "Intranasal corticosteroids", "E": "Oral antihistamines"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old woman comes to the emergency department because of fever, watery diarrhea, and abdominal cramping for the past 24 hours. She recently went to an international food fair. Her temperature is 39°C (102.2°F). Physical examination shows increased bowel sounds. Stool cultures grow gram-positive, spore-forming, anaerobic rods that produce alpha toxin. The responsible organism also causes which of the following physical examination findings?", "answer": "Subcutaneous crepitus", "options": {"A": "Diffuse, flaccid bullae", "B": "Facial paralysis", "C": "Subcutaneous crepitus", "D": "Rose spots", "E": "Petechial rash"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old woman comes to the physician for preconceptional advice. She has been married for 2 years and would like to conceive within the next year. Menses occur at regular 30-day intervals and last 4 days with normal flow. She does not smoke or drink alcohol and follows a balanced diet. She takes no medications. She is 160 cm (5 ft 3 in) tall and weighs 55 kg (121 lb); BMI is 21.5 kg/m2. Physical examination, including pelvic examination, shows no abnormalities. She has adequate knowledge of the fertile days of her menstrual cycle. Which of the following is most appropriate recommendation for this patient at this time?", "answer": "Begin folate supplementation", "options": {"A": "Begin folate supplementation", "B": "Begin high-dose vitamin A supplementation", "C": "Begin vitamin B12 supplementation", "D": "Begin iron supplementation", "E": "Gain 2 kg prior to conception"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old woman with a history of depression is brought to the emergency department by her husband 45 minutes after ingesting an unknown amount of a termite poison in a suicide attempt. She has abdominal pain, nausea, and vomiting. Her husband reports that she has had two episodes of watery diarrhea on the way to the emergency department. A distinct, garlic-like odor on the breath is noted on examination. An ECG shows sinus tachycardia and QTc prolongation. Administration of which of the following is most appropriate?", "answer": "Dimercaprol", "options": {"A": "N-acetylcysteine", "B": "Fomepizole", "C": "Deferoxamine", "D": "Physostigmine", "E": "Dimercaprol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 30-year-old patient comes to the emergency room with a chief complaint of left chest pain and a productive cough with purulent sputum for 1 week. He also complains of shortness of breath. He said he had been previously diagnosed with influenza but did not follow the doctor’s instructions. His vitals include: heart rate 70/min, respiratory rate 22/min, temperature 38.7°C (101.7°F), blood pressure 120/60 mm Hg, and SO2 80%. His hemogram and chest X-ray findings are as follows:\nHemoglobin 14 mg/dL\nHematocrit 45%\nLeukocyte count 12,000/mm3\nNeutrophils 82%\nLymphocytes 15%\nMonocytes 3%\nPlatelet count 270,000/mm3\nChest X-ray alveolar infiltrates in the left base with air bronchograms\nWhat is the most likely diagnosis?", "answer": "Pneumonia", "options": {"A": "Sarcoidosis", "B": "Pneumonia", "C": "Histoplasmosis", "D": "Lung cancer", "E": "Tuberculosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "While playing in the woods with friends, a 14-year-old African-American male is bitten by an insect. Minutes later he notices swelling and redness at the site of the insect bite. Which substance has directly led to the wheal formation?", "answer": "Histamine", "options": {"A": "IFN-gamma", "B": "Histamine", "C": "IL-22", "D": "Arachidonic acid", "E": "IL-4"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 76-year-old male with a history of chronic uncontrolled hypertension presents to the emergency room following an episode of syncope. He reports that he felt lightheaded and experienced chest pain while walking his dog earlier in the morning. He notes that he has experienced multiple similar episodes over the past year. A trans-esophageal echocardiogram demonstrates a thickened, calcified aortic valve with left ventricular hypertrophy. Which of the following heart sounds would likely be heard on auscultation of this patient?", "answer": "Crescendo-decrescendo murmur radiating to the carotids that is loudest at the right upper sternal border", "options": {"A": "Diastolic rumble following an opening snap with an accentuated S1", "B": "Early diastolic high-pitched blowing decrescendo murmur that is loudest at the left sternal border", "C": "Crescendo-decrescendo murmur radiating to the carotids that is loudest at the right upper sternal border", "D": "Holosystolic murmur radiating to the axilla that is loudest at the apex", "E": "Midsystolic click that is most prominent that is loudest at the apex"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 43-year-old Caucasian male spent the past month on a business trip in the Caribbean. Two weeks following his return, he began experiencing diarrhea, pain in his abdomen, and a headache. He presents to the hospital and is noted to be febrile with prominent rose-colored spots on his chest and abdomen. Following recovery, the patient may become a carrier of the bacteria with the bacteria heavily localized to the:", "answer": "Gallbladder", "options": {"A": "Gallbladder", "B": "Spleen", "C": "CD4 T-helper cells", "D": "Lungs", "E": "Sensory ganglia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A clinical study is studying new genetic gene-based therapies for children and adults with sickle cell disease. The patients were informed that they were divided into two age groups since younger patients suffer from different complications of the disease. The pediatric group is more likely to suffer from which of the complications?\nI. Splenic sequestration\nII. Avascular necrosis\nIII. Pulmonary hypertension\nIV. Acute chest syndrome\nV. Nephropathy", "answer": "I, IV", "options": {"A": "I, II", "B": "I, IV, V", "C": "I, II, IV", "D": "III, IV", "E": "I, IV"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 21-year-old Cambodian patient with a history of rheumatic heart disease presents to his primary care physician for a routine check-up. He reports being compliant with monthly penicillin G injections since being diagnosed with rheumatic fever at age 15. He denies any major side effects from the treatment, except for the inconvenience of organizing transportation to a physician's office every month. On exam, the patient is found to have a loud first heart sound and a mid-diastolic rumble that is best heard at the apex. Which of the following is the next best step?", "answer": "Continue intramuscular penicillin therapy", "options": {"A": "Stop penicillin therapy", "B": "Stop penicillin therapy in 4 years", "C": "Decrease frequency of injections to bimonthly", "D": "Switch to intramuscular cefotaxime, which has fewer side effects", "E": "Continue intramuscular penicillin therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old woman presents to the emergency department with muscle weakness. She reports her symptoms have progressively worsened over the course of 2 weeks and are most significant in her lower extremities. She also notices increased urinary frequency. Approximately 1 month ago she was diagnosed with a calcium phosphate nephrolithiasis. Medical history is significant for rheumatoid arthritis diagnosed approximately 10 years ago treated with methotrexate, and type II diabetes mellitus treated with metformin. Her temperature is 98.6°F (37°C), blood pressure is 138/92 mmHg, pulse is 92/min, and respirations are 17/min. On physical exam, there is mild tenderness to palpation of the metacarpophalangeal and proximal interphalangeal joints. There is 4/5 power throughout the lower extremity. Laboratory testing is shown.\n\nSerum:\nNa+: 137 mEq/L\nCl-: 106 mEq/L\nK+: 2.9 mEq/L\nHCO3-: 18 mEq/L\nGlucose: 115 mg/dL\nCreatinine: 1.0 mg/dL\nUrine pH: 5.6\n\nWhich of the following is the best next step in management?", "answer": "Administer intravenous sodium bicarbonate", "options": {"A": "Administer hydrochlorothiazide", "B": "Administer intravenous insulin", "C": "Administer intravenous sodium bicarbonate", "D": "Begin potassium replacement therapy with dextrose", "E": "Increase the methotrexate dose"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman comes to the office for a regular follow-up. She was diagnosed with type 2 diabetes mellitus 4 years ago. Her last blood test showed a fasting blood glucose level of 6.6 mmol/L (118.9 mg/dL) and HbA1c of 5.1%. No other significant past medical history. Current medications are metformin and a daily multivitamin. No significant family history. The physician wants to take her blood pressure measurements, but the patient states that she measures it every day in the morning and in the evening and even shows him a blood pressure diary with all the measurements being within normal limits. Which of the following statements is correct?", "answer": "The physician has to measure the patient’s blood pressure because it is a standard of care for any person with diabetes mellitus who presents for a check-up.", "options": {"A": "The physician should not measure the blood pressure in this patient and should simply make a note in a record showing the results from the patient’s diary.", "B": "The physician should not measure the blood pressure in this patient because she does not have hypertension or risk factors for hypertension.", "C": "The physician has to measure the patient’s blood pressure because it is a standard of care for any person with diabetes mellitus who presents for a check-up.", "D": "The physician should not measure the blood pressure in this patient because the local standards of care in the physician’s office differ from the national standards of care so measurements of this patient’s blood pressure can not be compared to diabet", "E": "Assessment of blood pressure only needs to be done at the initial visit; it is not necessary to measure blood pressure in this patient at any follow-up appointments."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old woman is brought to the emergency department for right hip pain 1 hour after she fell while walking around in her house. She has been unable to stand or walk since the fall. She has hypertension and gout. Her sister died of multiple myeloma at the age of 55 years. Current medications include amlodipine and febuxostat. She does not smoke cigarettes. She drinks a glass of wine daily. Her temperature is 37.3°C (99.1°F), pulse is 101/min, and blood pressure is 128/86 mm Hg. Examination shows right groin tenderness. Range of motion of the right hip is limited by pain. The remainder of the examination shows no abnormalities. A complete blood count and serum creatinine concentration are within the reference range. An x-ray of the hip shows a linear fracture of the right femoral neck. She is scheduled for surgery. Which of the following is the most likely underlying cause of this patient's fracture?", "answer": "Reduced osteoblastic activity", "options": {"A": "Reduced osteoblastic activity", "B": "Monoclonal antibody production", "C": "Interrupted vascular supply", "D": "Impaired bone mineralization", "E": "Defective osteoclast function"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old man presents as a new patient at an outpatient clinic. He has never seen a physician before, but was motivated by his 40-year-old brother's recent heart attack and seeks to optimize his health. In particular, he read that uncontrolled atherosclerosis can lead to a heart attack. Which molecule is downregulated in response to the advent of atherosclerosis?", "answer": "Nitric oxide", "options": {"A": "Serotonin", "B": "Thromboxane A2", "C": "Nitric oxide", "D": "Interleukin 1", "E": "Tumor necrosis factor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A newborn is brought to the emergency department by his parents with violent vomiting. It started about 3 days ago and has slowly gotten worse. He vomits after most feedings but seems to keep some formula down. His mother notes that he is eager to feed between episodes and seems to be putting on weight. Other than an uncomplicated course of chlamydia conjunctivitis, the infant has been healthy. He was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. The physical exam is significant for a palpable mass in the right upper quadrant. What is the first-line confirmatory diagnostic test and associated finding?", "answer": "Abdominal ultrasound; elongated pyloric channel and muscle hypertrophy", "options": {"A": "Abdominal X-ray; ‘double bubble’ sign", "B": "Barium upper GI series; GE junction and portion of the stomach in thorax", "C": "Barium upper GI series; bird beak sign and corkscrewing", "D": "Air enema; filling defect and coil spring sign", "E": "Abdominal ultrasound; elongated pyloric channel and muscle hypertrophy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old pregnant woman presents to the clinic with complaints of cramping, abdominal pain, and severe watery diarrhea for the past 3 days. She also is nauseous and complains of fever and malaise. She was started on a 7-day course of amoxicillin after being admitted to the hospital for pyelonephritis 5 days ago. The vital signs include heart rate 98/min, respiratory rate 16/min, temperature 38.9°C (102.0°F), and blood pressure 92/56 mm Hg. Physical examination reveals abdominal distention with diffuse tenderness. Laboratory studies show a peripheral white blood cell (WBC) count of 15,000/mm3 and stool guaiac positive for occult blood. Which of the following is the best pharmacotherapy for her condition?", "answer": "Oral vancomycin", "options": {"A": "Metronidazole", "B": "Rifaximin", "C": "IV metronidazole plus oral vancomycin", "D": "Oral vancomycin", "E": "Oral nitazoxanide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 26-year-old woman (gravida 3 para 1) with no prenatal care delivers a boy at 37 weeks gestation. His Apgar score is 5 at 1 minute and 8 at 5 minutes. His weight is 2.1 kg (4.2 lb) and length is 47 cm (1 ft 7 in). The mother’s history is significant for chronic pyelonephritis, atrial fibrillation, and gastroesophageal reflux disease. She has a 5-pack-year smoking history and also reports alcohol consumption during pregnancy. Examination of the infant shows a short depressed nasal bridge, wide nose, brachydactyly, and a short neck. Ophthalmoscopy reveals bilateral cataracts. What is the most likely cause of the newborn’s symptoms?", "answer": "Warfarin", "options": {"A": "Omeprazole", "B": "Gentamicin", "C": "Alcohol", "D": "Atenolol", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 8-year-old girl is brought to the physician because of repetitive involuntary movements, including neck twisting, grimacing, grunting, and blinking, for the past 18 months. Her symptoms seem to improve with concentration and worsen with fatigue. During the past 3 months, they have become so severe that she has missed many school days. Her mother says she also has too much anxiety about her involuntary movements to see her friends and prefers staying home in her room. Her birth and development until 18 months ago were normal. Her father suffers from bipolar disorder. Vital signs are within normal limits. Mental status examination shows intact higher mental function and thought processes. Neurological examination shows multiple motor and vocal tics. Physical examination is otherwise within normal limits. Which of the following is the most appropriate initial pharmacotherapy for this condition?", "answer": "Risperidone", "options": {"A": "Buspirone", "B": "Alprazolam", "C": "Risperidone", "D": "Fluoxetine", "E": "Chlorpromazine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man presents to his primary care provider with increased urinary frequency. Over the past 3 months, he has been urinating 2-3 times more often than usual. He has started to feel dehydrated and has increased his water intake to compensate. He works as a bank teller. He has a 25-pack-year smoking history and drinks 8-10 beers per week. His temperature is 98°F (36.8°C), blood pressure is 114/68 mmHg, pulse is 100/min, and respirations are 18/min. Capillary refill is 3 seconds. His mucous membranes appear dry. The patient is instructed to hold all water intake. Urine specific gravity is 1.002 after 12 hours of water deprivation. The patient is given desmopressin but his urine specific gravity remains relatively unchanged. Which of the following is the most appropriate pharmacologic treatment for this patient's condition?", "answer": "Metolazone", "options": {"A": "Desmopressin", "B": "Furosemide", "C": "Mannitol", "D": "Metolazone", "E": "Spironolactone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old boy comes to the physician because of a nonpruritic rash on his chest for 1 week. He returned from a trip to Puerto Rico 10 days ago. He started using a new laundry detergent after returning. He has type 1 diabetes mellitus controlled with insulin. His mother has Hashimoto thyroiditis, and his sister has severe facial acne. Examination of the skin shows multiple, nontender, round, hypopigmented macules on the chest and trunk. There is fine scaling when the lesions are scraped with a spatula. Which of the following is the most likely underlying mechanism of this patient's symptoms?", "answer": "Increased growth of Malassezia globosa", "options": {"A": "Autoimmune destruction of melanocytes", "B": "Increased sebum production", "C": "Increased growth of Malassezia globosa", "D": "Antigen uptake by Langerhans cells", "E": "Infection with Trichophyton rubrum"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A pharmaceutical company conducts a randomized clinical trial in an attempt to show that their new anticoagulant drug prevents more thrombotic events following total knee arthroplasty than the current standard of care. However, a significant number of patients are lost to follow-up or fail to complete treatment according to the study arm to which they were assigned. Several patients in the novel drug arm are also switched at a later time to a novel anticoagulant or warfarin per their primary care physician. All patients enrolled in the study are subsequently analyzed based on the initial group they were assigned to and there is a significant improvement in outcome of the new drug. What analysis most appropriately describes this trial?", "answer": "Intention to treat", "options": {"A": "As treated", "B": "Intention to treat", "C": "Modified intention to treat", "D": "Non-inferiority", "E": "Per protocol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old man comes to the physician for evaluation of a rash on the elbows for several months. A biopsy of the affected area shows a thinned stratum granulosum as well as retained nuclei and spongiotic clusters of neutrophils in the stratum corneum. This patient's skin findings are most likely associated with which of the following conditions?", "answer": "Seronegative spondylarthropathy", "options": {"A": "Seronegative spondylarthropathy", "B": "Hypersensitivity to gliadin", "C": "Infection with hepatitis C virus", "D": "Hashimoto thyroiditis", "E": "Insulin resistance"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman is brought to the emergency department 1 hour after being involved in a motor vehicle collision. She was riding a bike when she lost control and hit a car on the opposite side of the road. On arrival, she is unconscious. She has a history of intravenous heroin use. Her pulse is 56/min, respirations are 8/min and irregular, and blood pressure is 196/102 mm Hg. Examination shows a 2-cm laceration over the left cheek and a 3-cm laceration over the left chest. There are multiple abrasions over her face and chest. She opens her eyes and flexes her extremities to painful stimuli. The pupils are dilated and react sluggishly to light. There are decreased breath sounds over the left lung. The trachea is central. There is no jugular venous distention. Cardiac examination shows no abnormalities. The abdomen is soft and nontender. The left knee and right ankle are swollen; range of motion is limited. Two large-bore peripheral intravenous catheters are inserted. She is intubated and mechanical ventilation is initiated. A focused assessment with sonography in trauma is negative. An occlusive dressing is applied over the left chest wound. She is scheduled for a noncontrast CT scan of the brain. Which of the following is the underlying cause of this patient's hypertension?", "answer": "Elevated sympathetic response", "options": {"A": "Elevated sympathetic response", "B": "Reduced parasympathetic response", "C": "Increased intrathoracic pressure", "D": "Brainstem compression", "E": "Posttraumatic vasospasm"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old female presents to her primary care physician because of pain on her right foot. She says that the pain began 2 weeks ago and gets worse with weight bearing. She has been training for a marathon, and this pain has limited her training. On exam, there are no signs of inflammation or deformities on her foot. Compression of the forefoot with concomitant pressure on the interdigital space reproduces the pain on the plantar surface between the third and fourth toes and produces an audible click. What is the cause of this patient's condition?", "answer": "A benign neuroma", "options": {"A": "A bony outgrowth", "B": "Inflammation of the bursa", "C": "A benign neuroma", "D": "A metatarsal compression fracture", "E": "Inflammation and scarring of the plantar fascia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old Caucasian male complains of severe headache and pain while chewing. Upon examination, he is found to have a left visual field deficit. Laboratory results show elevated erythrocyte sedimentation rate. Which of the following drugs would be the best choice for treatment of this patient?", "answer": "Prednisone", "options": {"A": "Propranolol", "B": "Prednisone", "C": "Sumatriptan", "D": "Pilocarpine", "E": "Clopidogrel"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 62-year-old woman comes to the physician because of involuntary, rhythmic movements of her hands for the past 5 months. Her symptoms initially affected her left hand only, but now both hands are affected. She also reports that her symptoms are worse at rest and that performing tasks such as tying her shoelaces and writing have become more difficult. Her husband thinks that she has been more withdrawn lately. She used to drink a half a bottle of sherry every day for the past 18 years but has not consumed alcohol in the past year. She has chronic liver disease, hypertension, and peripheral artery disease. Current medications include aspirin and propanolol. She appears anxious. She is oriented to time, place, and person. Her temperature is 37°C (98.6°F), pulse is 98/min, and blood pressure is 144/82 mm Hg. Examination shows a rhythmic, low-frequency tremor that is more prominent in the left hand. Range of motion in the arms and legs is normal. Increased resistance to passive flexion and extension is present in the left upper limb. Muscle strength is 4/5 in all limbs. Sensations to pinprick and light touch are preserved. The finger-to-nose test is normal bilaterally. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Degeneration of the substantia nigra", "options": {"A": "Copper accumulation in the basal ganglia", "B": "Increased serum free T4 levels", "C": "Infarction of the red nucleus", "D": "Cerebellar infarction", "E": "Degeneration of the substantia nigra"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "During an experiment conducted to alter the infectivity of common viruses that affect humans, an investigator successfully increases the host range of human immunodeficiency virus (HIV). The new strain of the virus can infect fibroblast-like cells in addition to the usual target of HIV. Which of the following is the most likely explanation for the increase in the host range of the virus?", "answer": "Mutation of the gene coding for viral surface glycoproteins", "options": {"A": "Mutation of the gene coding for viral surface glycoproteins", "B": "Point mutations in the hemagglutinin gene", "C": "Increased rate of budding out of host cells", "D": "Reassortment of genetic material between segments of two viruses", "E": "Excessive activity of viral RNA polymerase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 66-year-old man with congestive heart failure presents to the emergency department complaining of worsening shortness of breath. These symptoms have worsened over the last 3 days. He has a blood pressure of 126/85 mm Hg and heart rate of 82/min. Physical examination is notable for bibasilar crackles. A chest X-ray reveals bilateral pulmonary edema. His current medications include metoprolol succinate and captopril. You wish to add an additional medication targeted towards his symptoms. Of the following, which statement is correct regarding loop diuretics?", "answer": "Loop diuretics inhibit the action of the Na+/K+/Cl- cotransporter", "options": {"A": "Loop diuretics decrease sodium, magnesium, and chloride but increase calcium", "B": "Loop diuretics inhibit the action of the Na+/K+/Cl- cotransporter", "C": "Loop diuretics can cause ammonia toxicity", "D": "Loop diuretics can cause metabolic acidosis", "E": "Loop diuretics can cause hyperlipidemia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old man comes to the physician because his skin has been progressively yellowing for the past 4 weeks. He also reports low appetite and difficulty fitting into his pants because of his swollen legs over the past several months. There is no personal or family history of serious illness. He does not smoke and drinks 1 to 2 beers on special occasions. He used to be sexually active with multiple female partners but has lost interest in sexual intercourse recently. He is 178 cm (5 ft 10 in) tall and weighs 68 kg (150 lb); his BMI is 22 kg/m2. Vital signs are within normal limits. Physical examination shows yellowing of the skin and sclera as well as erythema of the palms. There is bilateral enlargement of breast tissue. Cardiopulmonary examinations show no abnormalities. The abdomen is distended. The liver is palpated 2 to 3 cm below the right costal margin. On percussion of the left abdomen, a thrill can be felt on the right side. Hepatojugular reflux is absent. There is bilateral edema below the knees. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Chronic viral hepatitis", "options": {"A": "Chronic viral hepatitis", "B": "Congestive hepatopathy", "C": "Primary biliary cirrhosis", "D": "Autoimmune hepatitis", "E": "Non-alcoholic steatohepatitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old male presents to his primary care physician for complaints of dizziness. The patient reports he experiences room-spinning dizziness lasting several hours at a time, approximately 2-3 times a month, starting 3 months ago. Upon questioning, the patient also reports right sided diminished hearing, tinnitus, and a sensation of ear fullness. Her temperature is 99 deg F (37.2 deg C), pulse 70/min, respirations 12, blood pressure 130 mmHg/85 mmHg, SpO2 99%. You decide to order an audiometric evaluation. What is the most likely finding of the audiogram?", "answer": "Low frequency sensorineural hearing loss", "options": {"A": "Low frequency sensorineural hearing loss", "B": "High frequency sensorineural hearing loss", "C": "Low frequency conductive hearing loss", "D": "High frequency conductive hearing loss", "E": "Normal audiogram"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old man comes to the physician for a follow-up examination 1 week after being admitted to the hospital for oral candidiasis and esophagitis. His CD4+ T lymphocyte count is 180 cells/μL. An HIV antibody test is positive. Genotypic resistance assay shows the virus to be susceptible to all antiretroviral therapy regimens and therapy with dolutegravir, tenofovir, and emtricitabine is initiated. Which of the following sets of laboratory findings would be most likely on follow-up evaluation 3 months later?\n $$$ CD4 +/CD8 ratio %%% HIV RNA %%% HIV antibody test $$$", "answer": "↑ ↓ positive", "options": {"A": "↓ ↑ negative", "B": "↑ ↑ negative", "C": "↑ ↓ positive", "D": "↓ ↑ positive", "E": "↓ ↓ negative"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old U.S. born first year medical student with no prior hospital or healthcare work presents to the physician for a routine physical exam. The patient is HIV negative, denies drug use, and denies sick contacts. The physician places a purified protein tuberculin test in the patient's right forearm intradermally. What is the proper time to read the test and induration diameter that would indicate a positive test result?", "answer": "72 hours and 16mm diameter", "options": {"A": "24 hours and 18mm diameter", "B": "36 hours and 7mm diameter", "C": "48 hours and 11mm diameter", "D": "72 hours and 16mm diameter", "E": "96 hours and 14mm diameter"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 3-year-old boy is brought to the emergency department for nausea and vomiting for 1 day. His maternal uncle had a seizure disorder and died in childhood. He appears fatigued. Respirations are 32/min. Examination shows diffuse weakness in the extremities. Serum studies show a low pH, elevated lactate concentration, and normal blood glucose. A metabolic condition characterized by a defect in oxidative phosphorylation is suspected. Microscopic examination of a muscle biopsy specimen of this patient is most likely to show which of the following findings?", "answer": "Subsarcolemmal accumulation of mitochondria", "options": {"A": "Fibrofatty replacement of normal muscle fibers", "B": "Muscle atrophy with perimysial inflammation", "C": "Intermyofibrillar accumulation of glycogen", "D": "Endomysial inflammation with T cell infiltration", "E": "Subsarcolemmal accumulation of mitochondria"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-year-old boy presents to your office with loss of his peripheral vision. His mother discovered this because he was almost struck by a vehicle that \"he couldn't see at all\". In addition, he has been complaining of a headache for the last several weeks and had an episode of vomiting 2 days ago. He has a family history of migraines in his mother and grandmother. He is currently in the 80th percentile for height and weight. On physical exam his temperature is 99°F (37.2°C), blood pressure is 110/75 mmHg, pulse is 100/min, respirations are 19/min, and pulse oximetry is 99% on room air. He is uncooperative for the rest of the physical exam. During workup, a lesion is found in this patient. Which of the following would most likely be seen during histopathologic analysis?", "answer": "Cholesterol crystals and calcification", "options": {"A": "Rosettes and small blue cells", "B": "Eosinophilic, corkscrew fibers", "C": "Perivascular rosettes with rod-shaped blepharoplasts", "D": "Cholesterol crystals and calcification", "E": "Round nuclei with clear cytoplasm"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Researchers are experimenting with hormone levels in mice in fasting and fed states. To test hormone levels in the fed state, the mice are given an oral glucose load and various hormones are measured in a blood sample. Researchers are most interested in the hormone whose blood levels track evenly with C-peptide levels. The hormone the researchers are most interested in is responsible for which of the following actions in the body?", "answer": "Fatty acid synthesis", "options": {"A": "Fatty acid synthesis", "B": "Fatty acid breakdown", "C": "Protein catabolism", "D": "Ketogenesis", "E": "Lipolysis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman presents because of a painful mass she first noticed on her neck 1 week ago (see image). The mass has grown over the last few days. She has no history of serious illness and takes no medications. On physical exam, her temperature is 38.0°C (100.4°F), pulse is 86/min, respirations are 12/min, blood pressure is 135/80 mm Hg. The mass is tender and relatively soft and mobile. The overlying skin is warm. On her right ear, there is a series of small and healing skin punctures left by the bite of her neighbor’s kitten 3 weeks ago. No other mass is detected in the neck, supraclavicular, axillary, or inguinal regions. Oral examination reveals several discolored teeth. Her lungs are clear to auscultation and heart sounds are normal. Which of the following is the most appropriate diagnostic study at this time?", "answer": "Warthin-Starry silver stain for Bartonella henselae", "options": {"A": "Culture for facultative anaerobes", "B": "Histologic evaluation for Reed-Sternburg cells", "C": "The Monospot test for Epstein-Barr virus", "D": "Toxoplasma IgG using enzyme-linked immunosorbent assay", "E": "Warthin-Starry silver stain for Bartonella henselae"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old female who is 12 weeks pregnant presents to her primary care physician because she is concerned about her acne. While she has struggled with acne for most of her adult life, the acne has become more severe in the past few months. She has used benzoyl peroxide, salicylic acid, and topical antibiotics in the past but these treatments have had little effect. The patient would like to try minocycline, which worked for a friend of hers. The physician responds that this drug cannot be given to pregnant women, and offers to start the patient on the drug after she delivers the baby. Minocycline may to toxic to the fetus through which mechanism?", "answer": "Inhibition of bone growth", "options": {"A": "Inhibition of bone growth", "B": "Formation of renal cysts", "C": "Atrialization of the ventricle", "D": "Scarring of the bile ducts", "E": "Gray coloring of the skin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old man presents with a draining abscess on his left jaw. The patient states that he had a “bad tooth” a few weeks ago which has progressed to his current condition. His vital signs include: blood pressure 110/80 mm Hg, heart rate 85/min, and temperature 37.9°C (100.3°F). On physical examination, the patient has a 4 cm abscess on the left maxillary line that is draining a granulous, purulent material. Which of the following is the most likely causative organism of this abscess?", "answer": "Gram-positive, branching rod", "options": {"A": "Enveloped, double stranded DNA virus", "B": "Gram-positive cocci in clusters", "C": "Gram-positive cocci in chains", "D": "Gram-positive, branching rod", "E": "Aerobic gram-negative rod"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old obese female presents with new-onset headaches, ringing in her ears, and blurry vision. Ibuprofen and avoidance of light has not relieved her symptoms. She denies a history of recent trauma, fever, chills, and fatigue. Past medical history is significant for type 2 diabetes mellitus managed with metformin. She has had 20/20 vision her whole life and wonders if she might need to get eyeglasses. She has 2 healthy school-age children. Her temperature is 36.8°C (98.2°F), heart rate is 90/min, respiratory rate is 15/min, and blood pressure is 135/80 mm Hg. Physical exam is notable for decreased lateral eye movement, and the funduscopic findings are shown in the picture. Laboratory findings are within normal limits and brain imaging is normal. Lumbar puncture demonstrates an elevated opening pressure and normal CSF composition. Which of the following is a side effect of the medication used to treat this condition?", "answer": "Kidney stones", "options": {"A": "Kidney stones", "B": "Elevated liver function tests", "C": "Rhabdomyolysis", "D": "Decreased white blood cell count", "E": "Pancreatitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old gravida 1 para 1 woman is being seen in the hospital for breast tenderness. She reports that both breasts are swollen and tender. She is also having difficulty getting her newborn to latch. The patient gave birth 4 days ago by uncomplicated vaginal delivery. During her pregnancy, the patient developed gestational diabetes but was otherwise healthy. She took folate and insulin. She attended all her pre-natal appointments. Upon examination, the patient has a low grade fever, but all other vital signs are stable. Bilateral breasts appear engorged and are tender to palpation. There is no erythema, warmth, or induration. A lactation nurse is brought in to assist the patient and her newborn with more effective breastfeeding positions. The patient says a neighbor told her that breastmilk actually lacks in nutrients, and she asks what the best option is for the health of her newborn. Which of the following components is breastmilk a poor source of?", "answer": "Vitamin D", "options": {"A": "Immunoglobulin A", "B": "Lysozymes", "C": "Phosphorus", "D": "Vitamin D", "E": "Whey protein"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-month-old boy is brought to the pediatrician by his parents, who began noticing that the infant was not able to hold his head upright when sitting or in a prone position. Upon examination, the infant has a musty odor, fair skin with patches of eczema, and blue eyes. The pediatrician orders laboratory tests and prescribes a special diet. Which of the following substances should be included in this diet?", "answer": "Large neutral amino acids", "options": {"A": "Large neutral amino acids", "B": "L-carnitine", "C": "Thiamine", "D": "Malate", "E": "Arginine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old man comes to the emergency department because of a 3-week history of intermittent swelling of his left arm and feeling of fullness in his head that is exacerbated by lying down and bending over to tie his shoes. Physical examination shows left-sided facial edema and distention of superficial veins in the neck and left chest wall. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Apical lung tumor", "options": {"A": "Right heart failure", "B": "Cervical rib", "C": "Apical lung tumor", "D": "Subclavian steal syndrome", "E": "Mediastinal lymphoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old woman comes to the physician because of fatigue, irregular menses, and recurrent respiratory infections for the past 6 months. Her blood pressure is 151/82 mm Hg. Physical examination shows a round face, thinning of the skin, and multiple bruises on her arms. Further studies confirm the diagnosis of an ACTH-secreting pituitary adenoma. This patient is at greatest risk for which of the following?", "answer": "Pathologic fracture", "options": {"A": "Weight loss", "B": "Eosinophilia", "C": "Hypoglycemia", "D": "Bitemporal hemianopsia", "E": "Pathologic fracture"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 8-year-old boy is brought to the pediatric emergency department by his parents with a complaint of abdominal pain and diarrhea for the past week. He states that for the past two days, he has noticed blood in his stool. His parents note that they attended a neighbor’s barbecue last weekend, but otherwise have not eaten any new foods or changed their usual diet. The patient is admitted to the hospital unit for further work-up. The provider team finds that the patient’s blood is positive for Shiga-like toxin and notes the following lab values: creatinine of 4.2 mg/dL, platelet count of 50,000/mm^3, and hemoglobin of 6.0 g/dL. Which of the following additional lab findings would be consistent with the diagnosis?", "answer": "Microthrombi within glomerular vessels on kidney biopsy", "options": {"A": "Blunting of villi on ileal biopsy", "B": "Crypt abscesses and ulcers on colonic biopsy", "C": "Microthrombi within glomerular vessels on kidney biopsy", "D": "Foamy macrophages in intestinal lamina propria on duodenal biopsy", "E": "Sickling of red blood cells on peripheral blood smear"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old woman comes to the physician because of involuntary hand movements that improve with alcohol consumption. Physical examination shows bilateral hand tremors that worsen when the patient is asked to extend her arms out in front of her. The physician prescribes a medication that is associated with an increased risk of bronchospasms. This drug has which of the following immediate effects on the cardiovascular system?\n $$$ Stroke volume %%% Heart rate %%% Peripheral vascular resistance $$$", "answer": "↓ ↓ ↑", "options": {"A": "↑ ↑ ↓", "B": "↓ ↓ ↓", "C": "↓ ↑ ↑", "D": "↓ ↓ ↑", "E": "↑ ↑ ↑"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old girl is brought to the emergency department by her parents with sudden onset shortness of breath. They tell the emergency physician that their daughter was lying on the bed watching television when she suddenly began gasping for air. They observed a bowl of peanuts lying next to her when they grabbed her up and brought her to the emergency department. Her respirations are 25/min, the pulse is 100/min and the blood pressure is 90/65 mm Hg. The physical findings as of now are apparently normal. She is started on oxygen and is sent in for a chest X-ray. Based on her history and physical exam findings, the cause of her current symptoms would be seen on the X-ray at which of the following sites?\n ", "answer": "The superior segment of the right lower lobe", "options": {"A": "The apical segment of the right upper lobe", "B": "The apical segment of the left upper lobe", "C": "The superior segment of the right lower lobe", "D": "The posterior segment of the right lower lobe", "E": "The lingula of the right lower lobe"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An otherwise healthy 67-year-old woman comes to your clinic after being admitted to the hospital for 2 weeks after breaking her hip. She has not regularly seen a physician for the past several years because she has been working hard at her long-time job as a schoolteacher. You wonder if she has not been taking adequate preventative measures to prevent osteoporosis and order the appropriate labs. Although she is recovering from surgery well, she is visibly upset because she is worried that her hospital bill will bankrupt her. Which of the following best describes her Medicare coverage?", "answer": "Medicare Part A will cover the majority of her hospital fees, including inpatient drugs and lab tests.", "options": {"A": "Medicare Part A will cover the majority of her hospital fees, including inpatient drugs and lab tests.", "B": "Medicare Part B will cover the majority of her hospital fees, including inpatient drugs and lab tests.", "C": "Medicare Part C will cover the majority of drug costs during her inpatient treatment.", "D": "Medicare Part D will cover the cost of drugs during her inpatient treatment.", "E": "Medicare is unlikely to cover the cost of her admission because she has not been paying her premium."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman has painless abdominal distension 2 days after admission for acute pancreatitis. Her initial abdominal pain has resolved. Enteral nutrition has been initiated. She has not passed any stool since being admitted to the hospital. She has nausea but no vomiting. Her temperature is 36.7°C (98.1°F), pulse is 95/min, respiratory rate is 17/min, and blood pressure is 100/70 mm Hg. The lungs are clear to auscultation. Abdominal examination shows symmetric distention, absent bowel sounds, and tympanic percussion without tenderness. Laboratory studies show:\nSerum\nNa+ 137 mEq/L\nK+ 3.2 mEq/L\nCl− 104 mEq/L\nHCO3− 23 mEq/L\nUrea nitrogen 22 mg/dL\nCreatinine 0.8 mg/dL\nA supine abdominal X-ray is shown. Which of the following best explains these findings?", "answer": "Ileus", "options": {"A": "Ascites", "B": "Ileus", "C": "Necrotizing pancreatitis", "D": "Pancreatic fluid collection", "E": "Pancreatic pseudocyst"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying the changes that occur in the oxygen-hemoglobin dissociation curve of different types of hemoglobin under various conditions. The blood obtained from a male infant shows decreased affinity for 2,3-bisphosphoglyceric acid. Which of the following is the most likely composition of the hemoglobin molecule in this sample?", "answer": "α2γ2\n\"", "options": {"A": "β4", "B": "α2βS2", "C": "α2β2", "D": "α2δ2", "E": "α2γ2\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A research team is studying the effects of a novel drug that was discovered to treat type 2 diabetes. In order to learn more about its effects, they follow patients who are currently taking the drug and determine whether there are adverse effects that exceed anticipated levels and may therefore be drug-related. They discover that the drug causes an excess of sudden cardiac death in 19 patients with renal failure out of 2 million total patients that are followed. Based on these results, an additional warning about this serious adverse effect is added to the investigator brochure for the drug. Which of the following clinical phase studies does this study most likely describe?", "answer": "Phase IV", "options": {"A": "Phase I", "B": "Phase II", "C": "Phase III", "D": "Phase IV", "E": "Phase V"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old man presents to a physician with complaints of paresthesia of the lower extremities, which he has had for the last 3 months. He has been frequently fatigued for the past 5 months and also experienced an increased frequency of urination over the last few months. There is no history of a known medical condition or of substance abuse. His physical examination does not reveal any specific abnormality, except that he is obese: his body mass index is 34.6 kg/m2. The patient’s detailed laboratory evaluation reveals a fasting plasma glucose of 160 mg/dL and 2-hour plasma glucose of 270 mg/dL. His physician tells him that his laboratory evaluation suggests a diagnosis of diabetes mellitus type 2. The patient, surprised by this news, asks his physician why he has developed diabetes mellitus even though no one else in his family has ever suffered from it. The physician explains to him that genetic factors play an important role in the development of diabetes mellitus, but that their interactions are complex. Apart from neonatal diabetes mellitus and maturity-onset diabetes of the young (MODY), the development of diabetes mellitus cannot be explained by a single genetic mutation. Which of the following options best explains the genetics of the form of diabetes mellitus from which this man is suffering?", "answer": "Polygenic inheritance", "options": {"A": "Anticipation", "B": "Genomic imprinting", "C": "Natural selection", "D": "Polygenic inheritance", "E": "Synergistic epistasis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old man is brought to the emergency department 1 hour after injuring his genital area when he fell astride his backyard fence. He was trimming a tree from the fence when he lost his balance. His vital signs are within normal limits. Examination shows blood at the urethral meatus, perineal ecchymoses, and a scrotal hematoma. An x-ray of the pelvis shows swelling of the soft tissue but no other abnormalities. Which part of the urinary tract is most likely damaged in this patient?", "answer": "Bulbous urethra", "options": {"A": "Penile urethra", "B": "Anterior bladder wall", "C": "Bulbous urethra", "D": "Membranous urethra", "E": "Prostatic urethra"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "You are working in the emergency room of a children's hospital when a 4-year-old girl is brought in by ambulance due to \"difficulty breathing.\" The patient had been eating lunch on a school field trip when she suddenly complained of abdominal pain. Shortly thereafter, she was noted to have swelling of the lips, a rapidly developing red rash and difficulty breathing. In the ambulance her blood pressure was persistently 80/50 mmHg despite intramuscular epinephrine. In the course of stabilization and work up of the patient, you note an elevated tryptase level. What is the mechanism behind this elevated tryptase level?", "answer": "Cross-linking of IgE on mast cells", "options": {"A": "IgG production by plasma cells", "B": "IgM mediated complement activation", "C": "Cross-linking of IgE on mast cells", "D": "Antibody-antigen immune complexes", "E": "Cross-linking of IgG on mast cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 26-year-old man is brought to the emergency department by his friends because of blurred vision and slurred speech for the past 6 hours. He had some difficulty swallowing his food during lunch and has weakness in both arms. Two weeks ago, he had an upper respiratory infection that resolved spontaneously. He lives independently and returned from his grandparents' farm 2 days ago. He commonly consumes canned vegetables and fruits. He is alert and oriented to person, place, and time. His temperature is 37°C (98.6°F), pulse is 88/min, respirations are 10/min and labored, and blood pressure is 110/70 mm Hg. Examination shows bilateral nystagmus and ptosis. The pupils are dilated and not reactive to light. Muscle strength of the facial muscles and bilateral upper extremities is decreased. Upper extremity deep tendon reflexes are 1+ bilaterally. Cardiopulmonary examination shows no abnormalities. Which of the following is the most likely cause for this patient's symptoms?", "answer": "Toxin that inhibits ACh release", "options": {"A": "Chemical that inhibits acetylcholinesterase", "B": "Cell-mediated focal demyelination", "C": "Autoantibodies against ACh receptors", "D": "Toxin that inhibits ACh release", "E": "Autoantibodies against myelin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year old boy is brought into clinic for evaluation of possible scoliosis that was newly found on a routine exam at school. On exam, he is also noted to be in the 99th percentile for height and 70th percentile for weight. He appears to have abnormally long extremities as well as an upward lens dislocation on ophthalmologic exam. A mutation leading to a defect in which of the following proteins is the most likely cause of his condition?", "answer": "Fibrillin", "options": {"A": "Type I collagen", "B": "Type IV collagen", "C": "Elastin", "D": "Fibrillin", "E": "ATP7A"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old man comes to the physician because of malaise and dark urine for the past 5 days. He has also had recurrent episodes of sinus congestion, productive cough, and fever for 3 months. Additionally, he has noticed a rash on his arms and feet. He has seasonal allergic conjunctivitis treated with ketotifen eye drops. Vital signs are within normal limits. Examination shows several erythematous and necrotic papules on his arms and feet. He has inflamed nasopharyngeal mucosa and a perforated nasal septum. The nasal bridge is collapsed. Laboratory studies show:\nHemoglobin 11.3 g/dL\nLeukocyte count 12000/mm3\nPlatelet count 270,000/mm3\nESR 55 mm/hr\nSerum\nUrea nitrogen 28 mg/dL\nCreatinine 2.9 mg/dL\nAnti-DNA antibodies negative\nAntineutrophil cytoplasmic antibodies positive\nUrine\nProtein 2+\nGlucose negative\nRBC 35–37/hpf\nRBC casts numerous\nWhich of the following biopsy findings is most likely to be observed in this patient?\"", "answer": "Granulomatous vasculitis of small and medium-sized vessels", "options": {"A": "Tissue eosinophilia with granulomatous reactions", "B": "Nongranulomatous fibrinoid necrosis with infiltration of neutrophils", "C": "Immunoglobulin and complement deposits at the dermoepidermal junction", "D": "Granulomatous vasculitis of small and medium-sized vessels", "E": "Transmural necrotizing arteritis and fibrinoid necrosis in muscles\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 3-week-old boy is brought to the physician for the evaluation of poor feeding and recurrent episodes of vomiting. He was delivered at term after an uncomplicated pregnancy. He is at the 5th percentile for length and weight. Physical examination shows generalized hypotonia. Urinalysis shows increased propionic acid concentration. The finding on urinalysis is best explained by the breakdown of which of the following substances?", "answer": "Branched-chain amino acids", "options": {"A": "Even-chain fatty acids", "B": "Hexose monosaccharides", "C": "Branched-chain amino acids", "D": "Catechol-containing monoamines", "E": "Bicyclic nitrogenous bases"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 59-year-old man presents to the emergency department with a sudden-onset sensation that the room is spinning causing him to experience several episodes of nausea and vomiting. Upon arriving, the patient’s symptoms have resolved. He states his symptoms occurred as he was going to bed. He has never experienced this before, but felt extremely dizzy for roughly 3 minutes. He currently feels at his baseline. The patient is otherwise healthy and only has a history of eczema. His temperature is 97.7°F (36.5°C), blood pressure is 134/85 mmHg, pulse is 85/min, respirations are 13/min, and oxygen saturation is 98% on room air. Physical exam is notable for a healthy man with a normal gait. The patient has a physiologic nystagmus and his cranial nerve exam is unremarkable. The patient’s head is turned to the left and he is laid back on the stretcher, which exacerbates severe symptoms with a nystagmus notable. The patient’s symptoms improve after 2 minutes of being in this position. Which of the following is the most likely diagnosis?", "answer": "Benign paroxysmal positional vertigo", "options": {"A": "Benign paroxysmal positional vertigo", "B": "Labyrinthitis", "C": "Meniere disease", "D": "Vertebrobasilar stroke", "E": "Vestibular neuritis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old boy is brought to the physician because of progressive right knee pain for the past 3 months. He reports that the pain is worse at night and while doing sports at school. He has not had any trauma to the knee or any previous problems with his joints. His vital signs are within normal limits. Examination of the right knee shows mild swelling and tenderness without warmth or erythema; the range of motion is limited. He walks with an antalgic gait. Laboratory studies show an alkaline phosphatase of 180 U/L and an erythrocyte sedimentation rate of 80 mm/h. An x-ray of the right knee is shown. Which of the following is the most likely diagnosis?", "answer": "Osteosarcoma\n\"", "options": {"A": "Ewing sarcoma", "B": "Chordoma", "C": "Osteochondroma", "D": "Chondrosarcoma", "E": "Osteosarcoma\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "One hour after being admitted to the hospital for sharp, acute chest pain and diaphoresis, a 55-year-old woman with type 2 diabetes mellitus loses consciousness in the emergency department. There are no palpable pulses. Chest compressions are started. The patient has a history of breast cancer that was surgically treated 4 years ago. Prior to admission, the patient was on a long bus ride to visit her sister. Her medications include tamoxifen, atorvastatin, metoprolol, metformin, and insulin. Serum troponin levels are elevated. The cardiac rhythm is shown. Which of the following is the most appropriate next step in management?", "answer": "Intravenous epinephrine therapy", "options": {"A": "Intravenous glucagon therapy", "B": "Defibrillation", "C": "Coronary angiography", "D": "Intravenous epinephrine therapy", "E": "Intravenous dextrose therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy presents to the opthalmologist for a down- and inward dislocation of the lens in his left eye. On physical exam, the boy has a marfanoid habitus and mental retardation. Biochemical tests were performed to locate the exact defect in this boy. It was found that there was a significant reduction of the conversion of 5,10-methyltetrahydrofolate to 5-methyltetrahydrofolate. Which of the following is the diagnosis?", "answer": "Homocystinuria", "options": {"A": "Marfan syndrome", "B": "Homocystinuria", "C": "Alkaptonuria", "D": "Phenylketonuria", "E": "Maple syrup disease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old gravida 1, para 0 woman is brought to the hospital in labor at 39 weeks gestation. After 4 hours, she gives birth to a healthy appearing baby boy with APGAR scores of 7 at 1 minute and 9 at 5 minutes. She had limited prenatal screening but did have an ultrasound at 35 weeks that showed polyhydramnios. The next day, the neonate vomits greenish-yellow fluid after breastfeeding. This occurs 2 more times that day after feeding and several times between feedings. The next day, the neonate appears weak with difficulty latching to the breast and is dehydrated. The physician on duty is concerned and orders blood work, IV fluids, and the abdominal X-ray shown below. Which of the following disorders is most associated with the newborn’s condition?", "answer": "Trisomy 21", "options": {"A": "Trisomy 18", "B": "Trisomy 13", "C": "Trisomy 21", "D": "47 XXY", "E": "45 XO"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 39-year-old woman presents with progressive weakness, exercise intolerance, and occasional dizziness for the past 3 months. Past medical history is unremarkable. She reports an 18-pack-year smoking history and drinks alcohol rarely. Her vital signs include: temperature 36.6°C (97.8°F), blood pressure 139/82 mm Hg, pulse 98/min. Physical examination is unremarkable. Her laboratory results are significant for the following:\nHemoglobin 9.2 g/dL\nErythrocyte count 2.1 million/mm3\nMean corpuscular volume (MCV) 88 μm3\nMean corpuscular hemoglobin (MCH) 32 pg/cell\nLeukocyte count 7,500/mm3\nWhich of the following is the best next step in the management of this patient’s condition?", "answer": "Reticulocyte count", "options": {"A": "Serum ferritin level", "B": "C-reactive protein (CRP)", "C": "Reticulocyte count", "D": "Direct antiglobulin test", "E": "Bone marrow biopsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 71-year-old woman presents to the clinic after an X-ray that revealed compression fractures of her L1 and L2 vertebral bodies due to osteoporotic changes. The patient has a history of hypertension for which she takes hydrochlorothiazide, and rheumatoid arthritis, for which she has been taking prednisone for the last 2 years. The patient states that she had a dual-energy X-ray absorptiometry (DEXA) scan 3 years ago that was normal and attributes that finding to regularly taking calcium and vitamin D supplements since then. The patient states that her pain from the fractures is stopping her from participating in her regular activities, such as exercising and gardening. Which of the following is the main cause of her osteoporosis?", "answer": "Bone depletion due to chronic corticosteroid use", "options": {"A": "Decreased estrogen levels", "B": "Hydrochlorothiazide (HCTZ) therapy", "C": "Calcium malabsorption", "D": "Bone depletion due to chronic corticosteroid use", "E": "Undiagnosed hyperparathyroidism"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old male is brought in by ambulance to the emergency department after he was found unresponsive at home for an unknown length of time. Upon arrival, he is found to be severely altered and unable to answer questions about his medical history. Based on clinical suspicion, a panel of basic blood tests are obtained including an arterial blood gas, which shows a pH of 7.32, a pCO2 of 70, and a sodium bicarbonate level of 30 mg/dl. Which of the following is most likely the primary disturbance leading to the values found in the ABG?", "answer": "Respiratory acidosis", "options": {"A": "Metabolic acidosis", "B": "Metabolic alkalosis", "C": "Respiratory acidosis", "D": "Respiratory alkalosis", "E": "Mixed alkalosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man with hypertension and type 2 diabetes mellitus is brought to the emergency department 20 minutes after the onset of severe anterior chest pain and shortness of breath. He has smoked one pack of cigarettes daily for 30 years. He appears distressed. His pulse is 116/min, respirations are 22/min, and blood pressure is 156/88 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. A grade 3/6, high-pitched, blowing, diastolic murmur is heard over the right upper sternal border. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Tear in the tunica intima", "options": {"A": "Tear in the tunica intima", "B": "Fibrofatty plaque in the aortic wall", "C": "Obstruction of the pulmonary arteries", "D": "Rupture of a bulla in the lung", "E": "Perforation of the esophageal wall"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 19-year-old woman comes to the physician because of worsening pain with swallowing for 3 days and a dry sensation in the mouth over the past week. She has a history of asthma controlled with inhaled fluticasone and albuterol. Physical examination shows white plaques on the dorsal surface of the tongue and buccal mucosa that bleed when scraped off. Which of the following is the most appropriate pharmacotherapy?", "answer": "Nystatin", "options": {"A": "Triamcinolone", "B": "Nystatin", "C": "Acyclovir", "D": "Griseofulvin", "E": "Amphotericin B"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman presents with ongoing diplopia for 1 week. She has noticed that her diplopia is more prominent when she looks at objects in her periphery. It does not present when looking straight ahead. She does not have a fever, headache, ocular pain, lacrimation, blurring of vision, or changes in her color vision. She is a college student and is otherwise healthy. The neurological examination reveals that when she looks to the left, her right eye does not adduct while her left eye abducts with nystagmus. Furthermore, when she looks to the right, her left eye does not adduct while her right eye abducts with prominent nystagmus. Her pupils are bilateral, equal and reactive to light and accommodation. The convergence is normal. The rest of the cranial nerve examination is unremarkable. What is the next best step in the management of this patient?", "answer": "Magnetic resonance imaging (MRI) of the brain", "options": {"A": "Computed tomography (CT) scan of the head", "B": "Lumbar puncture", "C": "Magnetic resonance imaging (MRI) of the brain", "D": "Ophthalmology referral", "E": "Visual evoked potential"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old man is brought to the physician by his mother because of concerns about his recent behavior. Three months ago, the patient first reported hearing loud voices coming from the ceiling of his room. During this time, he has also become increasingly worried that visitors to the house were placing secret surveillance cameras. Mental status examination shows tangential speech with paranoid thoughts. Treatment for this patient's condition predominantly targets which of the following dopaminergic pathways?", "answer": "Mesolimbic pathway", "options": {"A": "Mesolimbic pathway", "B": "Thalamocortical pathway", "C": "Mesocortical pathway", "D": "Corticostriatal pathway", "E": "Nigrostriatal pathway"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 22-year-old woman at 30 weeks gestation presents to the obstetrician with the sudden onset of fever, headache, anorexia, fatigue, and malaise. She mentioned that she had eaten ice cream 3 days ago. Blood cultures show gram-positive rods that are catalase-positive and display distinctive tumbling motility in liquid medium. What is the most likely diagnosis?", "answer": "Listeriosis", "options": {"A": "Brucellosis", "B": "Influenza", "C": "Listeriosis", "D": "Legionnaires' disease", "E": "Tularaemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old woman presents to the emergency room because of severe back pain after a fall. She says that she was walking home from work when she slipped on a patch of ice on the sidewalk. Since she did not have anything to hold onto, she fell backwards and landed on her posterior iliac crests bilaterally. Immediately after the fall, she started experiencing back pain and tenderness that concerned her enough to call for an ambulance. Her past medical history is significant for arthritis, diabetes, and hypertension. On arrival, her temperature is 99°F (37.2°C), blood pressure is 129/86 mmHg, pulse is 112/min, respirations are 19/min. Physical exam reveals tenderness to palpation over the middle of her lower back. A drug that may have predisposed this patient to this outcome most likely has which of the following mechanisms?", "answer": "Inhibition of leukotriene and prostaglandin production", "options": {"A": "Inhibition of leukotriene and prostaglandin production", "B": "Inhibition of circulating cytokine", "C": "Inhibition of folate processing", "D": "Inhibition of prostaglandin production alone", "E": "Stimulation of adipocyte transcription factor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman presents for a follow-up visit. She was diagnosed with type 2 diabetes mellitus a month ago but refused to start medications despite counseling due to her fear of gaining weight. She tried exercising and eating healthy in an attempt to ''cure'' her diabetes. She managed to lose 1.8 kg (4 lb) in a month. Today she still complains of increased urinary frequency, the same symptom that leads to her initial suspicion of diabetes. No other significant past medical history. She is happily married and plans on having kids in the next few years. The patient is a non-smoker, denies illicit drug use, and drinks socially. Her vital signs show a pulse of 80/min, a respiratory rate of 16/min, a blood pressure of 120/80 mm Hg, and a temperature of 36.9°C (98.4°F). Her BMI is 33.0 kg/m2. Physical exam findings are unremarkable. Her fingerstick glucose today is 214 mg/dL. Laboratory findings reveal the following:\nGlycated Hemoglobin (HbA1c) 7.1%\nBlood glucose (fasting) 130 mg/dL\nSerum:\nSodium 142 mEq/L\nPotassium 3.9 mEq/L\nChloride 101 mEq/L\nSerum creatinine 0.8 mg/dL\nBlood urea nitrogen 9 mg/dL\nUrinalysis shows:\nGlucose Positive\nKetones Negative\nLeukocytes Negative\nNitrites Negative\nRBCs Negative\nCasts Negative\nWhich of the following is the best treatment option for this patient?", "answer": "Start metformin.", "options": {"A": "Start insulin.", "B": "Start glipizide.", "C": "Start metformin.", "D": "Start exenatide.", "E": "Start empagliflozin."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 30-year-old woman comes to the physician because of a 6-month history of a recurring rash that typically occurs on exposure to the sun and affects only the face. She also has noticed several nonpainful ulcers on the roof of her mouth. She is sexually active with one male partner and they use condoms inconsistently. Her mother has end-stage renal disease. The patient does not smoke or drink alcohol. Her vital signs are within normal limits. Physical examination shows an erythematous rash across the cheeks that spares the nasolabial folds. There are three small ulcers on the hard palate. Laboratory studies show:\nLeukocyte count 3,000/mm3\nPlatelet count 70,000/mm3\nErythrocyte sedimentation rate 80 mm/h\nSerum\nAntinuclear antibodies 1:320\nAnti-Smith antibodies positive\nUrine\nProtein 3+\nRBC casts negative\nRBCs none\nWBCs 10–15/hpf\nWhich of the following is the most appropriate next step in management?\"", "answer": "Renal biopsy", "options": {"A": "Skin biopsy", "B": "Renal biopsy", "C": "Administration of hydroxychloroquine", "D": "Administration of azathioprine", "E": "Pathergy skin testing"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 59-year-old man presents to the emergency room for a fever that has persisted for over 4 days. In addition, he has been experiencing weakness and malaise. His past medical history is significant for a bicuspid aortic valve that was replaced 2 years ago. Physical exam reveals nailbed splinter hemorrhages, tender nodules on his fingers, and retinal hemorrhages. An echocardiogram shows aortic valve vegetations and culture reveals a gram-positive alpha-hemolytic organism that grows as cocci in chains. The organism is then exposed to optochin and found to be resistant. Finally, they are seen to ferment sorbitol. The most likely cause of this patient's symptoms is associated with which of the following?", "answer": "Dental procedures", "options": {"A": "Colon cancer", "B": "Dental procedures", "C": "IV drug use", "D": "Pneumonia", "E": "Sexual activity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 2-year-old boy is brought to the physician by his mother after 2 days of fever, runny nose, hoarseness, and severe, dry cough. He appears restless. His temperature is 38.1°C (100.5°F), and his respiratory rate is 39/min. Examination shows clear rhinorrhea and a barking cough. There is a prolonged inspiratory phase with a harsh stridor upon agitation. An x-ray of the neck shows tapering of the subglottic region. Which of the following is the most likely causal organism?", "answer": "Parainfluenza virus", "options": {"A": "Adenovirus", "B": "Streptococcus pneumoniae", "C": "Haemophilus influenzae", "D": "Parainfluenza virus", "E": "Measles morbillivirus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-month-old boy is presented to the emergency department by his parents due to swelling in his right knee after playing in the park. His parents say there was no obvious injury. After questioning, the mother says that an uncle of hers had similar problems. The vital signs include heart rate 146/min, respiratory rate 26/min, temperature 37.1°C (98.8°F) and blood pressure 90/52 mm Hg. On physical examination, the swelling of the right knee is evident. The rest of the physical findings are unremarkable. The ultrasound is compatible with the hemarthrosis of the right knee. The complete blood count (CBC) results are as follows:\nHemoglobin 12.2 g/dL\nHematocrit 36%\nLeukocyte count 7,300/mm3\nNeutrophils 45%\nBands 3%\nEosinophils 1%\nBasophils 0%\nLymphocytes 44%\nMonocytes 2%\nPlatelet count 200,000/mm³\nThe coagulation test results are as follows:\nPartial thromboplastin time (activated) 52.0 s\nProthrombin time 14.0 s\nReticulocyte count 1.2%\nThrombin time < 2 seconds deviation from control\nWhat is the most likely diagnosis?", "answer": "Hemophilia A", "options": {"A": "Marfan syndrome", "B": "Von Willebrand disease", "C": "Ehler-Danlos disease", "D": "Hemophilia A", "E": "Bernard-Soulier disease"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man presents to the clinic for follow up for treatment of latent tuberculosis. He is a healthcare worker and began isoniazid 3 months ago after a routine PPD yielded a 12-mm induration. He feels otherwise well and attributes this to his vegetarian diet that he has been following for the past 4 years. His past medical history is unremarkable, but his family history is significant for a \"liver disease,\" the specifics of which are unknown. Physical exam shows mildly reduced sensation to pinprick over the distal lower extremities. The abdomen is soft, nontender, and without hepatosplenomegaly. Laboratory studies demonstrate the following:\n\nSerum:\nHemoglobin: 9.6 g/dL\nHematocrit: 34%\nLeukocyte count: 9,200/mm^3 with normal differential\nPlatelets: 270,000/mm^3\nMean corpuscular volume: 77 µm^3\nAST: 92 U/L\nALT: 84 U/L\nFerritin: 302 ng/mL (normal 15-200 ng/mL)\nTotal iron: 273 µg/dL (normal 50-170 µg/dL)\nTIBC: 150 µg/dL (normal 250–370 µg/dL)\n\nWhich of the following is the most appropriate next step in management?", "answer": "Pyridoxine supplementation", "options": {"A": "Blood lead levels", "B": "Cobalamin supplementation", "C": "Pyridoxine supplementation", "D": "Serial phlebotomy", "E": "Stop isoniazid treatment"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A case-control study with a focus on risk factors that may influence the development of depression was conducted among the elderly population in one tertiary hospital in Malaysia. The study involved 150 elderly patients diagnosed with depressive illness from the psychiatry ward, as well as another group of 150 elderly patients without any history of depressive illness (but hospitalized for other reasons) at the same ward. The data were collected through questionnaires, and 2 principal investigators (who were also the patients’ attending physicians) acted as interviewers after proper training for the purposes of this study. Multivariate analyses of logistic regression with independent variables were employed to determine the adjusted odds ratio for the risk of developing depression. The study results showed that a lower level of social support, lack of education, and the presence of chronic illnesses highly correlated with depression. In order to maximally avoid bias that may stem from this kind of study design, what should the researchers have done differently to increase the validity of their results?", "answer": "Blinded the investigators", "options": {"A": "Used open-ended questions", "B": "Included more interviewers", "C": "Blinded the investigators", "D": "Used Bonferroni correction on data", "E": "Used closed testing procedures on the data"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman presents with weight gain and a milky-white discharge from her breasts. Patient says she noticed herself gaining weight and a milky white discharge from her breasts. Past medical history is significant for schizophrenia, recently diagnosed and treated with risperidone. No history of headache, nausea, and vomiting. No other current medications. Her last menstrual period was 2 months ago. Review of systems is significant for decreased libido. Patient is afebrile and vital signs are within normal limits. On physical examination, patient had a weight gain of 3 kg (6.6 lb) over the past month. There is bilateral breast tenderness present. A urine pregnancy test is negative. Which of the following is the most likely etiology of this patient’s symptoms?", "answer": "Decrease in dopamine activity in tuberoinfundibular pathway", "options": {"A": "Decrease in dopamine activity in mesolimbic pathway", "B": "Increase in dopamine activity in mesolimbic pathway", "C": "Decrease in dopamine activity in tuberoinfundibular pathway", "D": "Increase in dopamine activity in tuberoinfundibular pathway", "E": "Decrease in dopamine activity in nigrostriatal pathway"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man is brought to the emergency department for the evaluation of severe chest pain for the last hour. The pain travels along the left arm and upper jaw. The patient also reports difficulty breathing and profuse sweating. He has hypertension and type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for the last 35 years. His medications include enalapril and metformin. His temperature is 37°C (98.6°F), pulse is 110/min, respirations are 20/min, and blood pressure is 90/60 mm Hg. An ECG shows ST elevation in the leads II, III, and aVF. Morphine is administered and oxygen supplementation and fluid resuscitation are begun. Shortly after, the patient becomes unstable. Following emergency resuscitation and stabilization, a written advance directive provided by the patient's primary care physician shows a do-not-resuscitate (DNR) order. The patient's wife, who is the power of attorney, disagrees. Which of the following is the most appropriate next step in management of this patient?", "answer": "Supportive care only", "options": {"A": "Obtain court order to revoke written advance directive", "B": "Supportive care only", "C": "Reperform resuscitation when needed", "D": "Contact the patient's oldest child", "E": "Contact the ethics committee"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 11-month-old boy is brought to a pediatrician by his parents for evaluation of vomiting and watery diarrhea over the last day. The mother informs the pediatrician that the boy had consumed an apple bought from a fruit vendor on the previous day, but that otherwise there has been no recent change in his diet. There is no history of blood in the stool, flatulence, irritability, or poor appetite. There is no history of recurrent or chronic diarrhea or any other gastrointestinal symptoms. On physical examination, his temperature is 37.6°C (99.6°F), pulse is 120/min, respirations are 24/min, and blood pressure is 92/60 mm Hg. General examination reveals a playful infant with normal skin turgor and no sunken eyes. The pediatrician explains to the parents that he most likely has acute gastroenteritis and that no specific medication is indicated at present. He also instructs the parents about his diet during the illness and reviews the danger signs of dehydration. He suggests a follow-up evaluation after 48 hours or earlier if any complications arise. Which of the following dietary recommendations did the pediatrician make?", "answer": "Age-appropriate diet", "options": {"A": "Age-appropriate diet", "B": "BRAT diet", "C": "Plenty of juices and carbonated sodas", "D": "Diluted formula milk", "E": "Lactose-free diet"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old female is brought to the emergency department after being found unconscious outside of a local night club by her friends. On arrival the patient is stuporous. Her temperature is 35°C (95°F), blood pressure is 105/75 mm Hg, pulse is 55/min, and respirations are 10/min. Examination shows dry mucous membranes. The pupils are small and react sluggishly to light. She does not respond to any commands, and painful stimuli cause her to withdraw all extremities. No injection marks can be found on her extremities. The remainder of the examination shows no abnormalities. Which of the following is the most likely cause of her symptoms?", "answer": "Heroin", "options": {"A": "Amitriptyline", "B": "Phencyclidine", "C": "MDMA", "D": "Heroin", "E": "Cannabis\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 5-year-old boy is brought to the physician because of increasing weakness and a retroauricular rash that started 2 days ago. The rash spread rapidly and involves the trunk and extremities. Last week, he had a mild sore throat, pink eyes, and a headache. His family recently immigrated from Ethiopia. His immunization status is unknown. The patient appears severely ill. His temperature is 38.5°C (101.3°F). Examination shows tender postauricular and suboccipital lymphadenopathy. There is a nonconfluent, maculopapular rash over the torso and extremities. Infection with which of the following is the most likely cause of this patient's symptoms?", "answer": "Togavirus", "options": {"A": "Togavirus", "B": "Varicella zoster virus", "C": "Parvovirus", "D": "Human herpesvirus 6", "E": "Paramyxovirus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 14-year-old girl is brought to the emergency department by her mother because of abdominal pain, nausea, and vomiting for 6 hours. Over the past 6 weeks, she has also had increased frequency of urination, and she has been drinking more water than usual. She has lost 6 kg (13 lb) over the same time period despite having a good appetite. Her temperature is 37.1°C (98.8°F), pulse is 125/min, respirations are 32/min, and blood pressure is 94/58 mm Hg. She appears lethargic. Physical examination shows deep and labored breathing and dry mucous membranes. The abdomen is soft, and there is diffuse tenderness to palpation with no guarding or rebound. Urine dipstick is positive for ketones and glucose. Further evaluation is most likely to show which of the following findings?", "answer": "Decreased total body potassium", "options": {"A": "Increased arterial pCO2", "B": "Increased arterial blood pH", "C": "Excess water retention", "D": "Serum glucose concentration > 800 mg/dL", "E": "Decreased total body potassium"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old woman with ongoing dyspnea returns to her physician for a follow-up appointment. After an abnormal echocardiogram and pulmonary function testing revealed an isolated reduction in DLCO, a right heart catheterization was ordered to confirm the physician's clinical suspicion. She has family members with similar findings and genetic testing revealed a mutation in the BMPR2 gene. A representative lesion from lung biopsy histology is shown in figure A. Given the patient's clinical presentation and test results, which of the following pharmacologic therapies will the physician most likely provide?", "answer": "Vasodilator", "options": {"A": "Plasmapheresis", "B": "Inhibitor of nitric oxide", "C": "Bronchodilator", "D": "Immunosuppression", "E": "Vasodilator"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An infant boy of unknown age and medical history is dropped off in the emergency department. The infant appears lethargic and has a large protruding tongue. Although the infant exhibits signs of neglect, he is in no apparent distress. The heart rate is 70/min, the respiratory rate is 30/min, and the temperature is 35.7°C (96.2°F). Which of the following is the most likely cause of the patient’s physical exam findings?", "answer": "Congenital agenesis of an endocrine gland in the anterior neck", "options": {"A": "Mutation in the WT2 gene", "B": "Congenital agenesis of an endocrine gland in the anterior neck", "C": "Excess growth hormone secondary to pituitary gland tumor", "D": "Type I hypersensitivity reaction", "E": "Autosomal dominant mutation in the SERPING1 gene"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old woman is brought to the emergency department because of worsening upper abdominal pain for 8 hours. She reports that the pain radiates to the back and is associated with nausea. She has hypertension and hyperlipidemia, for which she takes enalapril, furosemide, and simvastatin. Her temperature is 37.5°C (99.5 °F), blood pressure is 84/58 mm Hg, and pulse is 115/min. The lungs are clear to auscultation. Examination shows abdominal distention with epigastric tenderness and guarding. Bowel sounds are decreased. Extremities are warm. Laboratory studies show:\nHematocrit 48%\nLeukocyte count 13,800/mm3\nPlatelet count 175,000/mm3\nSerum:\nCalcium 8.0 mg/dL\nUrea nitrogen 32 mg/dL\nAmylase 250 U/L\nAn ECG shows sinus tachycardia. Which of the following is the most likely underlying cause of this patient's vital sign abnormalities?\"", "answer": "Capillary leakage", "options": {"A": "Hemorrhagic fluid loss", "B": "Decreased albumin concentration", "C": "Decreased cardiac output", "D": "Increased excretion of water", "E": "Capillary leakage"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 59-year-old man with a history of major depressive disorder, asthma, and erectile dysfunction presents to his family physician complaining of depressed mood, amotivation, overeating, and anhedonia. He currently takes no medications. The patient has a 3 pack-year smoking history and would like to quit but has been unsuccessful in the past. His BMI is 29 kg/m^2. The physician suggests starting an antidepressant for the patient's mood symptoms. The patient is reluctant, as he used to take sertraline, but stopped it after his erectile dysfunction worsened. Which of the following antidepressants would be most appropriate for this patient?", "answer": "Bupropion", "options": {"A": "Amitriptyline", "B": "Bupropion", "C": "Citalopram", "D": "Mirtazapine", "E": "Sertraline"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 70-year-old woman presents with a 2-week history of severe fatigue. Over the past month, she has unintentionally lost 2 kg (4.4 lb). Three years ago, she was diagnosed with myelodysplastic syndrome. Currently, she takes no medications other than aspirin for occasional knee pain. She does not smoke or drink alcohol. Her vital signs are within the normal range. On physical examination, her conjunctivae are pale. Petechiae are present on the distal lower extremities and on the soft and hard palates. Palpation reveals bilateral painless cervical lymphadenopathy. Examination of the lungs, heart, and abdomen shows no abnormalities. Laboratory studies show:\nHemoglobin 9 g/dL\nMean corpuscular volume 90 μm3\nLeukocyte count 3000/mm3\nPlatelet count 20,000/mm3\nA Giemsa-stained peripheral blood smear is shown in the image. Which of the following best explains these findings?", "answer": "Acute myeloid leukemia", "options": {"A": "Acute myeloid leukemia", "B": "Aplastic anemia", "C": "Chronic myelogenous leukemia", "D": "Hairy cell leukemia", "E": "Primary myelofibrosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 16-year-old man with no significant past medical, surgical, or family history presents to his pediatrician with new symptoms following a recent camping trip. He notes that he went with a group of friends and 1 other group member is experiencing similar symptoms. Over the past 5 days, he endorses significant flatulence, nausea, and greasy, foul-smelling diarrhea. He denies tenesmus, urgency, and bloody diarrhea. The blood pressure is 118/74 mm Hg, heart rate is 88/min, respiratory rate is 14/min, and temperature is 37.0°C (98.6°F). Physical examination is notable for mild, diffuse abdominal tenderness. He has no blood in the rectal vault. What is the patient most likely to report about his camping activities?", "answer": "Collecting water from a stream, without boiling or chemical treatment", "options": {"A": "Collecting water from a stream, without boiling or chemical treatment", "B": "Recent antibiotic prescription", "C": "This has been going on for months.", "D": "The patient camped as a side excursion from a cruise ship.", "E": "The patient camped in Mexico."}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old woman comes to the physician because of a 1-month history of multiple swellings in both her axillae. She says they are generally painless, but are sometimes painful on the weekends. She also has increased fatigue, recurring low-grade fevers, and generalized pruritus. She does not smoke. She drinks five to six beers on the weekends. Her temperature is 37°C (98.6°F), pulse is 80/min, respirations are 12/min, and blood pressure is 130/70 mm Hg. Physical examination reveals multiple firm and nontender axillary lymph nodes. A lymph node biopsy shows multinucleate giant lymphocytes with prominent nucleoli that resemble eosinophilic inclusions. Which of the following additional findings would be associated with a poor prognosis in this patient?", "answer": "Erythocyte sedimentation rate of 65 mm/h\n\"", "options": {"A": "Mediastinal tumor occupying 7% of the chest's width", "B": "Axillary tumor 6 cm across", "C": "Nodular lymphocyte predominant type tumor", "D": "Leukocyte count of 9,000/mm3", "E": "Erythocyte sedimentation rate of 65 mm/h\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 43-year-old man comes to the emergency room complaining of chest discomfort. He describes the feeling as \"tightness,\" and also reports weakness and palpitations for the past hour. He denies shortness of breath, diaphoresis, or lightheadedness. He has no significant past medical history, and does not smoke, drink, or use illicit drugs. His father had a myocardial infarction at age 72. He is afebrile, heart rate is 125 bpm, and his blood pressure is 120/76. He is alert and oriented to person, place, and time. His electrocardiogram is shown below. Which of the following tests should be ordered in the initial work-up of this patient's condition?", "answer": "Thyroid stimulating hormone level (TSH)", "options": {"A": "Urine free cortisol level", "B": "Blood alcohol level", "C": "Chest x-ray", "D": "Thyroid stimulating hormone level (TSH)", "E": "Urine metanephrines"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 11-year-old African American boy is brought to your office by his parents with a 1-day history of severe left hip pain. It is too painful for him to walk without support. He took ibuprofen, which brought no relief. He has had no chills or sweats. Similar painful episodes in the past required multiple hospitalizations. He returned from a trip to Kenya with his family 2 months ago. His vaccinations are up-to-date. His temperature is 38°C (100.4° F), pulse is 100/min, blood pressure is 120/80 mm Hg. Physical examination shows pale conjunctivae. The abdomen is soft with no organomegaly. Passive movement of the hip causes severe pain. There is tenderness on palpation, but no swelling, warmth, or erythema of the hip. His laboratory studies show a hematocrit of 25% and leukocyte count of 14 000/mm3. A peripheral blood smear would most likely show which of the following?", "answer": "Howell-Jolly bodies", "options": {"A": "Trophozoites", "B": "Decreased number of thrombocytes", "C": "Decreased number of reticulocytes", "D": "Howell-Jolly bodies", "E": "Gram-negative bacilli\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A researcher is studying the brains of patients who recently died from stroke-related causes. One specimen has a large thrombus in an area of the brain that is important in relaying many modalities of sensory information from the periphery to the sensory cortex. Which of the following embryologic structures gave rise to the part of the brain in question?", "answer": "Diencephalon", "options": {"A": "Telencephalon", "B": "Diencephalon", "C": "Mesencephalon", "D": "Metencephalon", "E": "Mylencephalon"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old man is brought to the emergency department after being involved in a bar fight. Physical examination shows tenderness to palpation over the left side of the back. An x-ray of the chest shows a fracture of the 12th rib on the left side. Further evaluation is most likely to show which of the following injuries?", "answer": "Kidney laceration", "options": {"A": "Liver hematoma", "B": "Pneumothorax", "C": "Colon perforation", "D": "Kidney laceration", "E": "Pancreatic transection"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 71-year-old African American man is brought to the emergency department with a worsening productive cough and dyspnea for 2 days. He has had generalized bone pain for 2 months. He was admitted for pyelonephritis last month. He also received outpatient treatment for pneumonia almost 2 months ago. Over the past 2 months, he has been taking over-the-counter ibuprofen for pain as needed. He appears anxious. The vital signs include: temperature 38.8°C (101.8°F), pulse 95/min, respiratory rate 20/min, and blood pressure 155/90 mm Hg. The conjunctivae are pale. Crackles are heard in the right lower lobe. The cardiac examination shows no abnormalities. The laboratory studies show the following:\nHemoglobin 9 g/dL\nMean corpuscular volume 95 μm3\nLeukocyte count 13,500/mm3\nSegmented neutrophils 75%\nLymphocytes 25%\nPlatelet count 240,000/mm3\nESR 85 mm/hr\nSerum\nNa+ 135 mEq/L\nK+ 4.2 mEq/L\nCl− 113 mEq/L\nHCO3− 20 mEq/L\nCa+ 12.4 mg/dL\nAlbumin 4 g/dL\nUrea nitrogen 38 mg/dL\nCreatinine 2.2 mg/dL\nA chest X-ray shows a right lower lobe opacity and blurring of the ipsilateral diaphragmatic dome. Skull and pelvic X-rays are performed (see image). Which of the following is the most likely underlying cause of this patient’s recent infections?", "answer": "Hypogammaglobulinemia", "options": {"A": "Advanced age", "B": "Hypogammaglobulinemia", "C": "NSAID-induced chronic kidney disease", "D": "T cell dysfunction", "E": "Unresolved pneumonia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old man comes to the physician because of a 4-month history of intermittent headaches. They have been getting progressively worse and no longer respond to ibuprofen. He also complains of weight gain and excessive sweating. Physical examination shows prominent supraorbital ridges, prognathism, macroglossia with thick lips, and disproportionately broad hands and feet. There is decreased peripheral vision bilaterally on visual field testing. An MRI of the brain shows a mass in the sella turcica. Genetic analysis of a biopsy specimen from the mass shows cells that overexpress adenylyl cyclase. Which of the following is the most appropriate pharmacotherapy for this condition?", "answer": "Octreotide", "options": {"A": "Methimazole", "B": "Octreotide", "C": "Leuprolide", "D": "Risperidone", "E": "Metyrapone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 10-year-old boy comes for a post-operative clinic visit with his ENT surgeon three months after airway reconstruction surgery and placement of a tracheostomy tube. Since the surgery, he says that he has been able to breathe better and is now getting used to tracheostomy care and tracheostomy tube changes. In addition to this surgery, he has had over twenty surgeries to implant hearing aids, reconstruct his cheekbones, and support his jaw to enable him to swallow. He was born with these abnormalities and had difficult breathing, hearing, and eating throughout his childhood. Fortunately, he is now beginning to feel better and is able to attend public school where he is one of the best students in the class. Abnormal development of which of the following structures is most likely responsible for this patient's malformations?", "answer": "First branchial arch", "options": {"A": "First branchial arch", "B": "First branchial pouch", "C": "Second branchial arch", "D": "Second branchial cleft", "E": "Third and fourth branchial pouches"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old man presents to the emergency department with a rapid change in his behavior. The patient recently returned from a vacation in rural Mexico and recovered from several episodes of bloody diarrhea. He has had a notable and rapid decline in his memory which started this morning. His personality has also changed, has not been sleeping, and seems generally apathetic. Brief and involuntary muscle twitches have been noted as well. The patient has a past medical history of hypertension and diabetes. His temperature is 99.8°F (37.7°C), blood pressure is 152/98 mmHg, pulse is 97/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is notable for a confused and apathetic man who is not compliant with the neurological exam. The patient is admitted to the ICU; however, during his hospital course, the patient ultimately dies. Which of the following was most likely to be found in this patient upon initial presentation?", "answer": "Sharp wave complexes on EEG", "options": {"A": "Blood in the subarachnoid place", "B": "Multifocal infarction on MRI", "C": "Neurofibrillary tangles", "D": "Sharp wave complexes on EEG", "E": "Tear of a bridging vein"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 71-year-old woman with a past medical history of type 2 diabetes, hypercholesterolemia, and hypertension was admitted to the hospital 8 hours ago with substernal chest pain for management of acute non-ST-elevated myocardial infarction (NSTEMI). The ECG findings noted by ST-depressions and T-wave inversions on anterolateral leads, which is also accompanied by elevated cardiac enzymes. Upon diagnosis, management with inhaled oxygen therapy, beta-blockers and aspirin, and low-molecular-weight heparin therapy were initiated, and she was placed on bed rest with continuous electrocardiographic monitoring. Since admission, she required 2 doses of sublingual nitric oxide for recurrent angina, and the repeat troponin levels continued to rise. Given her risk factors, plans were made for early coronary angiography. The telemetry nurse calls the on-call physician because of her concern with the patient’s mild confusion and increasing need for supplemental oxygen. At bedside evaluation, The vital signs include: heart rate 122/min, blood pressure 89/40 mm Hg, and the pulse oximetry is 91% on 6L of oxygen by nasal cannula. The telemetry and a repeat ECG show sinus tachycardia. She is breathing rapidly, appears confused, and complains of shortness of breath. On physical exam, the skin is cool and clammy and appears pale and dull. She has diffuse bilateral pulmonary crackles, and an S3 gallop is noted on chest auscultation with no new murmurs. She has jugular venous distention to the jaw-line, rapid and faint radial pulses, and 1+ dependent edema. She is immediately transferred to the intensive care unit for respiratory support and precautions for airway security. The bedside sonography shows abnormal hypodynamic anterior wall movement and an ejection fraction of 20%, but no evidence of mitral regurgitation or ventricular shunt. The chest X-ray demonstrates cephalization of pulmonary veins and pulmonary edema. What is the most appropriate next step in the stabilization of this patient?", "answer": "Initiate dopamine therapy and diuresis", "options": {"A": "Insert two large-bore intravenous catheters and start rapid fluid resuscitation", "B": "Initiate dopamine therapy and diuresis", "C": "Start intravenous fluids and epinephrine therapy", "D": "Obtain blood cultures and start preliminary broad-spectrum antibiotics", "E": "Intubate the patient and perform an emergency cardiocentesis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old woman is brought to the physician by her husband because of a 1-year history of abnormal behavior. During this time she has been irritable, restless, and has had multiple episodes of hearing voices. Over the past month, she has also had difficulty swallowing. She has a 2-year history of depression. She was let go by her employer 6 months ago because she could no longer handle all her tasks and often forgot about assignments. Her father committed suicide at the age of 50. The patient has smoked one pack of cigarettes daily over the past 20 years. She has a history of smoking cocaine for 8 years but stopped 1 year ago. Vital signs are within normal limits. On mental status examination, she is confused and oriented to person and place only. Neurologic examination shows a delayed return to neutral ankle position after triggering the plantar reflex. Physical examination shows irregular, nonrepetitive, and arrhythmic movements of the neck and head. The patient has poor articulation. Which of the following is the most likely diagnosis?", "answer": "Huntington disease", "options": {"A": "Sydenham chorea", "B": "Parkinson disease", "C": "Multiple sclerosis", "D": "Drug-induced chorea", "E": "Huntington disease"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 64-year-old woman has progressively worsening abdominal pain 5 hours after an open valve replacement with cardiopulmonary bypass. The pain is crampy and associated with an urge to defecate. The patient reports having had 2 bloody bowel movements in the last hour. Her operation was complicated by significant intraoperative blood loss, which prolonged the operation and necessitated 2 transfusions of red blood cells. She has hypercholesterolemia and type 2 diabetes mellitus. The patient received prophylactic perioperative antibiotics and opioid pain management during recovery. Her temperature is 37.9°C (98.9°F), pulse is 95/min, and blood pressure is 115/69 mm Hg. Examination shows a soft abdomen with mild tenderness to palpation in the left quadrants but no rebound tenderness or guarding. Bowel sounds are decreased. Rectal examination shows blood on the examining finger. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Decreased blood flow to the splenic flexure", "options": {"A": "Embolization of superior mesenteric artery", "B": "Decreased blood flow to the splenic flexure", "C": "Small outpouchings in the sigmoid wall", "D": "Atherosclerotic narrowing of the intestinal vessels", "E": "Infection with Clostridioides difficile"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 8-month-old boy is brought to the emergency department by his mother. She is concerned that her son has had intermittent periods of severe abdominal pain over the past several days that has been associated with emesis and \"currant jelly\" stool. Of note, the family lives in a rural part of the state, requiring a 2 hour drive to the nearest hospital. He currently appears to be in significant pain and has vomited twice in the past hour. On physical examination, a sausage-shaped mass is noted on palpation of the right upper quadrant of the abdomen. Ultrasound of the abdomen was consistent with a diagnosis of intussusception. An air-contrast barium enema was performed, which confirmed the diagnosis and also successfully reduced the intussusception. Which of the following is the next best step in the management of this patient?", "answer": "Admit to hospital for 24 hour observation for complications and/or recurrence", "options": {"A": "Discharge to home with follow-up in 3 weeks in an outpatient pediatric gastroenterology clinic", "B": "Repeat barium enema q6 hrs to monitor for recurrence", "C": "Keep patient NPO and initiate work-up to identify lead-point", "D": "Admit to hospital for 24 hour observation for complications and/or recurrence", "E": "Pursue urgent surgical reduction with resection of necrotic segments of bowel"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old woman presents to her primary care physician with complaints of persistent fatigue, dizziness, and weight loss for the past 3 months. She has a history of hypothyroidism and takes thyroxine replacement. Her blood pressure is 90/60 mm Hg in a supine position and 65/40 mm Hg while sitting, temperature is 36.8°C (98.2°F), and pulse is 75/min. On physical examination, there is a mild increase in thyroid size, with a rubbery consistency. Her skin shows diffuse hyperpigmentation, more pronounced in the oral mucosa and palmar creases. Which of the following best represent the etiology of this patient’s condition?", "answer": "Autoimmune destruction of the adrenal gland", "options": {"A": "Autoimmune destruction of the adrenal gland", "B": "↓ adrenocorticotropic hormone secretion from the pituitary gland", "C": "↓ corticotropin-releasing hormone secretion from the hypothalamus", "D": "Prolonged corticosteroid therapy", "E": "↑ iron absorption and deposition in the body"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 19-year-old man with a history of generalized tonic-clonic seizures comes to the physician for a routine health maintenance examination. He is a known user of intravenous cocaine. His vital signs are within normal limits. Physical examination shows multiple hyperpigmented lines along the forearms. Oral examination shows marked overgrowth of friable, ulcerated gingival mucosa. Which of the following is the most likely cause of this patient's oral examination findings?", "answer": "Phenytoin", "options": {"A": "Phenytoin", "B": "Lamotrigine", "C": "Lacosamide", "D": "Cyclosporine", "E": "Carbamazepine\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old man with prostate cancer comes to the physician because of low back pain for 2 weeks and a 4.5-kg (10-lb) weight loss. Physical examination shows localized tenderness over the lumbar spine. An x-ray of the lumbar spine shows several osteoblastic lesions at the level of L2 and L4 vertebrae. Microscopic examination of a bone biopsy specimen from the L4 vertebra shows irregular bone trabeculae and star-shaped cells with long, cytoplasmic processes located deep within the lacunae. Exchange of nutrients and waste products between these cells most likely occurs through which of the following structures?", "answer": "Macula communicans", "options": {"A": "Macula adherens", "B": "Macula communicans", "C": "Zonula occludens", "D": "Hemidesmosomes", "E": "Zonula adherens"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-week-old female newborn is brought to the physician because of increasing yellow discoloration of her eyes and skin for 2 days. She was born at 39 weeks' gestation and weighed 3066 g (6 lb 12 oz); she now weighs 3200 g (7 lb 1 oz). She is exclusively breastfed. Her older brother died 3 months after liver surgery. Her temperature is 37.1°C (98.8°F), pulse is 145/min, and respirations are 40/min. Examination shows yellow discoloration extending to the palms and soles. The liver is palpated 1 cm below the right costal margin. Laboratory studies show:\nHematocrit 51%\nSerum\nBilirubin\nTotal 16.1 mg/dL\nDirect 0.7 mg/dL\nAlkaline phosphatase 22 U/L\nAST 12 U/L\nALT 12 U/L\nWhich of the following is the most likely diagnosis?\"", "answer": "Breast milk jaundice", "options": {"A": "Biliary atresia", "B": "Physiologic neonatal jaundice", "C": "Isoimmune mediated hemolysis", "D": "Breast milk jaundice", "E": "Breastfeeding failure jaundice"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A researcher is trying to determine whether a newly discovered substance X can be useful in promoting wound healing after surgery. She conducts this study by enrolling the next 100 patients that will be undergoing this surgery and separating them into 2 groups. She decides which patient will be in which group by using a random number generator. Subsequently, she prepares 1 set of syringes with the novel substance X and 1 set of syringes with a saline control. Both of these sets of syringes are unlabeled and the substances inside cannot be distinguished. She gives the surgeon performing the surgery 1 of the syringes and does not inform him nor the patient which syringe was used. After the study is complete, she analyzes all the data that was collected and performs statistical analysis. This study most likely provides which level of evidence for use of substance X?", "answer": "Level 1", "options": {"A": "Level 1", "B": "Level 2", "C": "Level 3", "D": "Level 4", "E": "Level 5"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 13-year-old boy is brought to a physician with severe fevers and headaches for 3 days. The pain is constant and mainly behind the eyes. He has myalgias, nausea, vomiting, and a rash for one day. Last week, during an academic winter break, he traveled on a tour with his family to several countries, including Brazil, Panama, and Peru. They spent many evenings outdoors without any protection against insect bites. There is no history of contact with pets, serious illness, or use of medications. The temperature is 40.0℃ (104.0℉); the pulse is 110/min; the respiratory rate is 18/min, and the blood pressure is 110/60 mm Hg. A maculopapular rash is seen over the trunk and extremities. Several tender lymph nodes are palpated in the neck on both sides. A peripheral blood smear shows no organisms. Which of the following is most likely responsible for this patient’s presentation?", "answer": "Dengue fever", "options": {"A": "Babesiosis", "B": "Chagas disease", "C": "Dengue fever", "D": "Malaria", "E": "Zika virus"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old male comes to his family physician with complaints of joint pain that has been present for over 7 weeks. Prior to the onset of his arthritis, he recalls having a gastrointestinal infection which caused mild diarrhea and abdominal cramps. He recovered well and had no issues until his joint pain started. A prescription for naproxen was previously prescribed but he still does not feel well. He has no significant past medical or family history. On physical examination, his blood pressure is 120/78 mm Hg, respirations are 17/min, pulse is 64/min, and temperature is 36.7°C (98.0°F). Which of the following therapies is likely to be most beneficial in treating this patient’s condition?", "answer": "Sulfasalazine", "options": {"A": "Diclofenac", "B": "Sulfasalazine", "C": "Methotrexate", "D": "Ketoprofen", "E": "Ceftriaxone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old man presents to the emergency department with a 2-day history of fever and altered mentation. He reports fever without chills and rigors and denies sore throat, abdominal pain, headache, loose stool, burning micturition, or seizures. He has a history of tics and is currently on a low dose of haloperidol. At the hospital, his temperature is 39.6°C (103.2°F); the blood pressure is 126/66 mm Hg, and the pulse is 116/min. He is profusely sweating and generalized rigidity is present. He is confused and disoriented. He is able to move all his limbs. Normal deep tendon reflexes are present with bilateral downgoing plantar responses. A brain MRI is unremarkable. Urine toxicology is negative. The white blood cell count is 14,700/mm3. Creatine kinase is 5600 U/L. Lumbar puncture is performed and cerebrospinal fluid (CSF) studies show:\nCSF opening pressure 22 cm H20\nCSF white blood cells 4 cells/mm3\nCSF red blood cells 0 cells/mm3\nCSF glucose 64 mg/dL\nCSF protein 48 mg/dL\nSerum glucose 96 mg/dL\nWhat is the most likely diagnosis?", "answer": "Neuroleptic malignant syndrome", "options": {"A": "Acute disseminated encephalomyelitis", "B": "Cerebral venous sinus thrombosis", "C": "Encephalitis", "D": "Meningitis", "E": "Neuroleptic malignant syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 10-month-old boy is brought to the physician by his mother for evaluation of abnormal growth and skin abnormalities. His mother has also noticed that his eyes do not fully close when sleeping. He is at the 24th percentile for height, 17th percentile for weight, and 29th percentile for head circumference. Physical examination shows wrinkled skin, prominent veins on the scalp and extremities, and circumoral cyanosis. Genetic testing shows a point mutation in a gene that encodes for a scaffold protein of the inner nuclear membrane. The mutation causes a deformed and unstable nuclear membrane, which leads to premature aging. Which of the following is most likely to be the defective protein?", "answer": "Lamin", "options": {"A": "Desmin", "B": "Nesprin", "C": "Vimentin", "D": "Lamin", "E": "Plectin\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old man presents to his primary care physician because of a tremor that he has developed over the last several months. He says that the tremor is worst when he is resting but becomes better when he engages in movements such as picking up the remote for his TV. His wife also says that his movements have become slower over the last few months. Physical exam reveals increased resistance to passive motion of his extremities. Gait exam also shows trouble with starting movement and short, shuffling steps. The most likely cause of this patient's symptoms involve the degeneration of a certain subset of neurons. When the substance released by these neurons interact with a G-alpha-s coupled receptor, which of the following effects occurs?", "answer": "Inhibition of the globus pallidus internus", "options": {"A": "Inhibition of the globus pallidus externus", "B": "Inhibition of the globus pallidus internus", "C": "Stimulation of the globus pallidus externus", "D": "Stimulation of the globus pallidus internus", "E": "Stimulation of the subthalamic nucleus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 49-year-old woman presents to her physician with complaints of breast swelling and redness of the skin over her right breast for the past 1 month. She also mentions that the skin above her right breast appears to have thickened. She denies any pain or nipple discharge. The past medical history is significant for a total abdominal hysterectomy at 45 years of age. Her last mammogram 1 year ago was negative for any pathologic changes. On examination, the right breast was diffusely erythematous with gross edema and tenderness and appeared larger than the left breast. The right nipple was retracted and the right breast was warmer than the left breast. No localized mass was palpated. Which of the following statements best describes the patient’s most likely condition?", "answer": "The inflammation is due to obstruction of dermal lymphatic vessels.", "options": {"A": "It is a benign lesion.", "B": "The inflammation is due to obstruction of dermal lymphatic vessels.", "C": "The lesion expresses receptors for estrogen and progesterone.", "D": "The lesion is due to Streptococcal infection.", "E": "It shows predominant lymphatic spread."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old primigravid woman at 26 weeks' gestation comes to the physician complaining of absent fetal movements for the last 2 days. Pregnancy was confirmed by ultrasonography 14 weeks earlier. She has no vaginal bleeding or discharge. She has a history of type 1 diabetes mellitus controlled with insulin. Vital signs are all within the normal limits. Pelvic examination shows a soft, 2-cm long cervix in the midline with a cervical os measuring 3 cm and a uterus consistent in size with 24 weeks' gestation. Transvaginal ultrasonography shows a fetus with no cardiac activity. Which of the following is the most appropriate next step in management?", "answer": "Plan for oxytocin administration", "options": {"A": "Perform cesarean delivery", "B": "Plan for oxytocin administration", "C": "Administer magnesium sulfate", "D": "Perform weekly pelvic ultrasound", "E": "Perform dilation and curettage\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 63-year-old man presents to his primary care physician complaining of excessive daytime sleepiness. He explains that this problem has worsened slowly over the past few years but is now interfering with his ability to play with his grandchildren. He worked previously as an overnight train conductor, but he has been retired for the past 3 years. He sleeps approximately 8-9 hours per night and believes his sleep quality is good; however, his wife notes that he often snores loudly during sleep. He has never experienced muscle weakness or hallucinations. He has also been experiencing headaches in the morning and endorses a depressed mood. His physical exam is most notable for his large body habitus, with a BMI of 34. What is the best description of the underlying mechanism for this patient's excessive daytime sleepiness?", "answer": "Poor oropharyngeal tone", "options": {"A": "Insufficient sleep duration", "B": "Circadian rhythm sleep-wake disorder", "C": "Poor oropharyngeal tone", "D": "Deficiency of the neuropeptides, orexin-A and orexin-B", "E": "Psychiatric disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 5-year-old boy is brought to the physician with a recurring fever and malaise for 3 weeks. He has also had fatigue and loss of appetite. He initially presented 2 weeks ago with a maculopapular rash that has since resolved. At the time, he was given a prescription for amoxicillin-clavulanate. He denies sore throat or myalgias. He is home-schooled and has had no sick contacts. There are no pets at home, but he often visits a feline animal shelter where his mother volunteers. His temperature is 38.4°C (101.2°F). Physical examination shows a 1-cm papular lesion on the back of the right hand. He also has tender, bulky lymphadenopathy of the axillae and groin. Which of the following is the most appropriate next step in management?", "answer": "Azithromycin therapy", "options": {"A": "Doxycycline therapy", "B": "Pyrimethamine therapy", "C": "Itraconazole therapy", "D": "Azithromycin therapy", "E": "Streptomycin therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year-old girl is brought to the physician by her parents because of difficulty sleeping. One to two times per week for the past 2 months, she has woken up frightened in the middle of the night, yelling and crying. She has not seemed confused after waking up, and she is consolable and able to fall back asleep in her parents' bed. The following day, she seems more tired than usual at school. She recalls that she had a bad dream and looks for ways to delay bedtime in the evenings. She has met all her developmental milestones to date. Physical examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Nightmare disorder", "options": {"A": "Sleep terror disorder", "B": "Post-traumatic stress disorder", "C": "Normal development", "D": "Nightmare disorder", "E": "Separation anxiety disorder\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 56-year-old man who underwent kidney transplantation 6 months ago, presents to the physician because of fever, dyspnea, non-productive cough, and lethargy. He is on no other medications apart from immunosuppressive therapy. On physical examination, the vital signs include: pulse 110/min, blood pressure 126/76 mm Hg, respirations 26/min, oxygen saturation 80% at room air, and temperature 37.7°C (99.9°F). Chest auscultation is normal except for occasional bilateral wheezes. An X-ray of the chest shows diffuse interstitial infiltrates. Bronchoalveolar lavage is performed and methenamine silver staining confirms a parasitic infestation. Which of the following is the most appropriate pharmacotherapy for the patient?", "answer": "Trimethoprim-sulfamethoxazole intravenously", "options": {"A": "Intravenous pentamidine", "B": "Trimethoprim-sulfamethoxazole intravenously", "C": "Trimethoprim-sulfamethoxazole orally", "D": "High-dose corticosteroids and bronchodilators", "E": "Oral dapsone + trimethoprim"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 63-year-old man presents to the clinic complaining of burning bilateral leg pain which has been increasing gradually over the past several months. It worsens when he walks but improves with rest. His past medical and surgical history are significant for hypertension, hyperlipidemia, diabetes, and a 40-pack-year smoking history. His temperature is 99.0°F (37.2°C), blood pressure is 167/108 mm Hg, pulse is 88/min, respirations are 13/min, and oxygen saturation is 95% on room air. Physical exam of the lower extremities reveals palpable but weak posterior tibial and dorsalis pedis pulses bilaterally. Which of the following is the best initial treatment for this patient's symptoms?", "answer": "Exercise and smoking cessation", "options": {"A": "Balloon angioplasty with stenting", "B": "Exercise and smoking cessation", "C": "Femoral-popliteal bypass", "D": "Lisinopril and atorvastatin", "E": "Lovenox and atorvastatin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old woman, gravida 2, para 1, comes to the physician because she had a positive pregnancy test at home. During the last two weeks, she has had nausea and two episodes of non-bloody vomiting. She also reports increased urinary frequency. Her pregnancy and delivery of her first child were uncomplicated. Last year, she had two episodes of grand-mal seizure. She is sexually active with her husband and they use condoms inconsistently. She does not smoke or drink alcohol. She does not use illicit drugs. Current medications include valproic acid and a multivitamin. Her vital signs are within normal limits. Physical examination shows no abnormalities. A urine pregnancy test is positive. The child is at increased risk for requiring which of the following interventions?", "answer": "Lower spinal surgery", "options": {"A": "Cochlear implantation", "B": "Kidney transplantation", "C": "Respiratory support", "D": "Lower spinal surgery", "E": "Dental treatment"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 71-year-old man comes to the physician accompanied by his wife because of a 6-month history of worsening episodic upper abdominal pain and an 8-kg (17.6-lb) weight loss. The pain is dull, nonradiating, worse after eating, and occasionally associated with bloating and diarrhea. His symptoms have not improved despite 4 weeks of treatment with omeprazole. He attributes his weight loss to recently eating very small portions and avoiding fatty foods. He has hypertension and hypercholesterolemia. He underwent a coronary artery bypass graft operation for coronary artery disease 8 years ago. Current medications include lisinopril, metoprolol, atorvastatin, and aspirin. He has smoked a pack of cigarettes daily for 20 years and drinks 1–2 beers daily. His pulse is 79/min and blood pressure is 138/89 mm Hg. Examination shows a soft abdomen without tenderness to palpation or guarding. Which of the following is most likely to confirm the diagnosis?", "answer": "CT angiography of the abdomen", "options": {"A": "Serum CA 19-9", "B": "Right upper quadrant abdominal ultrasound", "C": "CT angiography of the abdomen", "D": "Endoscopic retrograde cholangiography", "E": "Upper endoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Five days after admission into the ICU for drug-induced acute kidney injury, a 27-year-old woman develops fever. She is currently on a ventilator and sedatives. Hemodialysis is performed via a catheter placed in the right internal jugular vein. Feeding is via a nasogastric tube. An indwelling urinary catheter shows minimum output. Her blood pressure is 85/45 mm Hg, the pulse is 112/min, the respirations are 32/min, and the temperature is 39.6°C (103.3°F). The examination of the central catheter shows erythema around the insertion site with no discharge. Lung auscultation shows rhonchi. Cardiac examination shows no new findings. A chest CT scan shows bilateral pleural effusions with no lung infiltration. Empirical antibiotic therapy is initiated. Blood cultures obtained from peripheral blood and the catheter tip show S. aureus with a similar antibiogram. Urinary culture obtained from the indwelling catheter shows polymicrobial growth. Which of the following best explains this patient’s recent findings?", "answer": "Central catheter-related bacteremia", "options": {"A": "Catheter-associated urinary tract infection", "B": "Central catheter-related bacteremia", "C": "Endocarditis", "D": "Naso-gastric tube sinusitis", "E": "Ventilator-associated pneumonia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 70-year-old man presents for his annual check-up. He says he feels well except for occasional abdominal pain. He describes the pain as 4/10–5/10 in intensity, diffusely localized to the periumbilical and epigastric regions, radiating to the groin. The pain occurs 1–2 times a month and always subsides on its own. The patient denies any recent history of fever, chills, nausea, vomiting, change in body weight, or change in bowel and/or bladder habits. His past medical history is significant for hypertension, hyperlipidemia, and peripheral vascular disease, managed with lisinopril and simvastatin. The patient reports a 40-pack-year smoking history and 1–2 alcoholic drinks a day. The blood pressure is 150/100 mm Hg and the pulse is 80/min. Peripheral pulses are 2+ bilaterally in all extremities. Abdominal exam reveals a bruit in the epigastric region along with mild tenderness to palpation with no rebound or guarding. There is also a pulsatile abdominal mass felt on deep palpation at the junction of the periumbilical and the suprapubic regions. The remainder of the physical exam is normal. Laboratory studies show:\nSerum total cholesterol 175 mg/dL\nSerum total bilirubin 1 mg/dL\nSerum amylase 25 U/L\nSerum alanine aminotransferase (ALT) 20 U/L\nSerum aspartate aminotransferase (AST) 16 U/L\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Abdominal aortic aneurysm", "options": {"A": "Abdominal aortic aneurysm", "B": "Acute pancreatitis", "C": "Mesenteric ischemia", "D": "Acute gastritis", "E": "Diverticulitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Six days after undergoing a left hemicolectomy for colorectal carcinoma, a 59-year-old man collapses in the hospital hallway and is unconscious for 30 seconds. Afterwards, he complains of shortness of breath and chest pain with deep inhalation. He has hypertension and hyperlipidemia. He smoked one pack of cigarettes daily for 35 years but quit prior to admission to the hospital. He does not drink alcohol. He is in distress and appears ill. His temperature is 36.5°C (97.7°F), blood pressure is 80/50 mm Hg, and pulse is 135/min and weak. Oxygen saturation is 88% on room air. Physical examination shows elevated jugular venous distention. Cardiac examination shows a regular, rapid heart rate and a holosystolic murmur that increases during inspiration. His abdomen is soft and mildly tender to palpation around the surgical site. Examination of his extremities shows pitting edema of the left leg. His skin is cold and clammy. Further examination is most likely to reveal which of the following findings?", "answer": "Dilated right ventricular cavity", "options": {"A": "Rapid, aberrant contractions of the atria", "B": "Stenosis of the carotid arteries", "C": "Dilated right ventricular cavity", "D": "Anechoic space between pericardium and epicardium", "E": "Reduced regional ventricular wall motion"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old woman presents to her physician with a complaint of pain and stiffness in her hands. She says that the pain began 6 weeks ago a few days after she had gotten over a minor upper respiratory infection. She admits that the pain is worse in the morning, and she occasionally notes subjective fever but has not taken her temperature. She also admits that her appetite has mildly decreased, but she denies any change in weight. The pain is partially alleviated by ibuprofen, but she has been unsatisfied with the results. She is concerned about her condition as it makes caring for her two young children very difficult. Temperature is 99.4°F (37.4°C), blood pressure is 119/73 mmHg, pulse is 75/min, and respirations are 18/min. Physical examination demonstrates swelling and tenderness over the wrists and metacarpophalangeal joints bilaterally. Bilateral radiographs of the hands demonstrate mild periarticular osteopenia around the left fifth metacarpophalangeal joint. Which of the following is the next best step in management of this patient's acute symptoms?", "answer": "Prednisone", "options": {"A": "Anakinra", "B": "Etanercept", "C": "Methotrexate", "D": "Reassurance", "E": "Prednisone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 15-year-old girl is brought to the physician because of abnormal vaginal bleeding for the past 2 months. Apart from the past 2 months, she has had regular menstrual cycles. She had menarche at the age of 13. She has no personal or family history of any serious illnesses. She takes no medications. Her vital signs are within normal limits. Physical examination shows no abnormal findings. Laboratory studies show elevated serum beta-HCG and AFP levels. An abdominal ultrasound shows a predominantly solid mass in the left ovary. The right ovary and the uterus show no abnormal findings. Which of the following ovarian tumors best explains these findings?", "answer": "Embryonal carcinoma", "options": {"A": "Corpus luteum cyst", "B": "Embryonal carcinoma", "C": "Fibromas", "D": "Krukenberg tumor", "E": "Serous cystadenoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-year-old boy presents with a swollen face and irritability. The patient's mother reports his urine was red this morning. 3 weeks ago, he presented to this same clinic with a ‘sandpaper’ rash and a red tongue with patchy hyperplastic fungiform papillae for which he was given broad-spectrum antibiotics. Laboratory tests reveal proteinuria, elevated antistreptolysin O, and decreased serum C3. Which of the following conditions mentioned below are triggered by a similar mechanism?\nI. Arthus reaction\nII. Myasthenia gravis\nIII. Acute rheumatic fever\nIV. Polyarteritis nodosa\nV. Rheumatoid arthritis", "answer": "I, IV, V", "options": {"A": "I, II", "B": "III, IV", "C": "I, IV, V", "D": "II, III, IV", "E": "I, IV, V"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 37-year-old woman presents to the general medical clinic with a chief complaint of anxiety. She has been having severe anxiety and fatigue for the past seven months. She has difficulty concentrating and her work has suffered, and she has also developed diarrhea from the stress. She doesn't understand why she feels so anxious and is unable to attribute it to anything specific aspect of her life right now. You decide to begin pharmacotherapy. All of the following are suitable mechanisms of drugs that can treat this illness EXCEPT:", "answer": "A drug that blocks dopamine 2 receptors", "options": {"A": "A drug that stimulates 5-HT1A receptors", "B": "A drug that blocks 5-HT reuptake", "C": "A drug that blocks both serotonin and norepinephrine reuptake", "D": "A drug that acts as a GABA agonist", "E": "A drug that blocks dopamine 2 receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old female is brought to the emergency room by her parents shortly after a suicide attempt by aspirin overdose. Which of the following acid/base changes will occur FIRST in this patient?", "answer": "Respiratory alkalosis", "options": {"A": "Non-anion gap metabolic acidosis", "B": "Anion gap metabolic acidosis", "C": "Respiratory acidosis", "D": "Metabolic alkalosis", "E": "Respiratory alkalosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "During a humanitarian medical mission in rural Vietnam, a medical resident encounters a 50-year-old man with a year-long history of a pruritic rash on his upper body and face, along with numbness and tingling sensation of both of his palms. He mostly works on his family’s rice farm, where he also takes care of livestock. A physical examination revealed multiple erythematous macules and papules on the face, arms, chest, and back, as well as thinning of the eyebrows and loss of some eyelashes. Additional findings include hypopigmented macules around the elbows, which are insensitive to light touch, temperature, and pinprick. The grip strength is slightly diminished bilaterally with the conservation of both bicipital reflexes. What is the most likely diagnosis?", "answer": "Leprosy", "options": {"A": "Cutaneous leishmaniasis", "B": "Sporotrichosis", "C": "Tinea corporis", "D": "Leprosy", "E": "Scrofula"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 21-year-old female is brought to the emergency department by her roommate. Her roommate says that the patient has been acting “strangely” for the past 10 days. She has noticed that the patient has been moving and talking on the phone at all hours of the night. She doesn’t think that the patient sleeps more than one to two hours a night. She also spends hours pacing up and down the apartment, talking about “trying to save the world.” She also notices that the patient has been speaking very fast. When asking the patient if anything seems different, the patient denies anything wrong, only adding that, “she’s made great progress on her plans.\" The patient said she has felt like this on one occasion 2 years ago, and she recalled being hospitalized for about 2 weeks. She denies any history of depression, although she said about a year ago she had no energy and had a hard time motivating herself to go to class and see her friends for months. She denies hearing any voices or any visual hallucinations. What is the most likely diagnosis in this patient?", "answer": "Bipolar I disorder", "options": {"A": "Schizoaffective disorder", "B": "Major depressive disorder", "C": "Bipolar I disorder", "D": "Bipolar II disorder", "E": "Dysthymic disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 87-year-old woman is brought to the emergency department 30 minutes after a fall onto a hardwood floor. She landed on her left side and hit the left side of her head. She did not lose consciousness. She has a mild headache over the left temple and severe left hip pain. She has had nasal congestion, a sore throat, and a productive cough for the last 2 days. She has a history of atrial fibrillation, coronary artery disease, hypertension, and osteoporosis. She underwent two coronary artery bypass grafts 5 years ago. She had smoked one pack of cigarettes daily for 30 years but quit 30 years ago. Her current medications include aspirin, apixaban, diltiazem, omeprazole, and vitamin D supplementation. The patient is oriented to person, place, and time. There is a 2-cm ecchymosis over the left temple. Examination of the left hip shows swelling and tenderness; range of motion is limited. Intravenous morphine 2 mg is started. During further examination, the patient complains of dizziness and palpitations. She is diaphoretic and pale. Her skin is cold and clammy. Her pulse is 110/min and faint, respirations are 20/min, and blood pressure is 70/30 mm Hg. Cranial nerves are intact. Cardiac examinations shows no murmurs, rubs, or gallops. An ECG shows absent P waves and nonspecific changes of the ST segment and the T wave. Which of the following is the most likely underlying mechanism for the patient's sudden decline in her condition?", "answer": "Blood loss", "options": {"A": "Pulmonary embolism", "B": "Cardiac tamponade", "C": "Brain herniation", "D": "Sepsis", "E": "Blood loss"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old male presents with primary complaints of a palpable mass in his scrotum and mild testicular pain. Physical exam reveals an abnormal appearing scrotum around the left testis, as depicted in image A. Which of the following is the most likely etiology of this presentation?", "answer": "Compression of the left renal vein at the aortic origin of the superior mesenteric artery", "options": {"A": "Compression of the left renal vein at the aortic origin of the superior mesenteric artery", "B": "Patent processus vaginalis allowing fluid entry into the scrotum", "C": "Neisseria gonorrhoeae Infection of the left testis leading to epididymitis", "D": "Unilateral failure of the left testis to descend into the scrotum", "E": "Twisting of the spermatic cord secondary to rotation of the left testis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 30-month-old boy is brought to the emergency department by his parents. He has burns over his left hand. The mother tells the doctor that the child was playing unobserved in the kitchen and accidentally grabbed a hot spoon, which produced the burn. She also says his pediatrician had expressed concern as to the possibility of autism spectrum disorder during the last visit and had suggested regular follow-up. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. On physical examination, his temperature is 37.0°C (98.6°F), pulse rate is 140/min, and respiratory rate is 28/min. He is irritable and crying excessively. On examination, the skin of the left hand is white-pink with small blisters over the entire dorsal aspect of the hand, but the skin of the palmar surface is undamaged. There is a sharp demarcation between healthy skin above the wrist and the injured skin of the hand. There are no burns or another injury anywhere else on the child. Which of the following is the most likely cause of the burns?", "answer": "Forced immersion in hot water", "options": {"A": "Forced immersion in hot water", "B": "Burn as a result of poor supervision", "C": "Cigarette burns", "D": "Accidental burns", "E": "Abusive burn from a hot spoon"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 75-year-old man is brought to the emergency department for a 5-day-history of worsening dyspnea, orthopnea, and lower leg swelling. He has a history of hypertension, hyperlipidemia, non-alcoholic fatty liver disease, and myocardial infarction 10 years ago. Current medications include metoprolol, lisinopril, ethacrynic acid, eplerenone, and aspirin. He drinks 1 beer daily. He has a 30-pack-year smoking history. He is allergic to sulfonamides. His temperature is 37.0°C (98.6°F), his pulse is 120/min, and his blood pressure is 120/80 mm Hg. Physical examination reveals jugular venous distention and 3+ pitting edema in his lower legs. Crackles are heard at both lung bases. The point of maximal impulse is 2 cm to the left of the midclavicular line in the 6th intercostal space. Which of the following additional findings would be most strongly associated with increased mortality?", "answer": "Decreased serum Na+", "options": {"A": "Decreased BNP levels", "B": "Decreased serum Na+", "C": "Decreased QRS complex duration", "D": "Increased VO2", "E": "Increased heart rate variability"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "You have been asked to quantify the relative risk of developing bacterial meningitis following exposure to a patient with active disease. You analyze 200 patients in total, half of which are controls. In the trial arm, 30% of exposed patients ultimately contracted bacterial meningitis. In the unexposed group, only 1% contracted the disease. Which of the following is the relative risk due to disease exposure?", "answer": "[30 / (30 + 70)] / [1 / (1 + 99)]", "options": {"A": "[30 / (30 + 70)] / [1 / (1 + 99)]", "B": "(30 * 99) / (70 * 1)", "C": "[70 / (30 + 70)] / [99 / (1 + 99)]", "D": "(70 * 1) / (39 * 99)", "E": "[1 / (1 + 99)] / 30 / (30 + 70)]"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A father brings in his 7-year-old twin sons because they have a diffuse rash. They have several papules, vesicles, pustules, and crusts on their scalps, torso, and limbs. The skin lesions are pruritic. Other than that, the boys appear to be well. The father reports that several children in school have a similar rash. The family recently returned from a beach vacation but have not traveled internationally. Both boys have stable vital signs within normal limits. What is the most common complication of the infection the boys appear to have?", "answer": "Bacterial superinfection of skin lesions", "options": {"A": "Hepatitis", "B": "Bacterial superinfection of skin lesions", "C": "Pneumonia", "D": "Encephalitis", "E": "Cerebellar ataxia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 75-year-old female comes to the physician’s office with complaints of right lower quadrant pain. She has been experiencing these symptoms for the last 6 months and they have progressively gotten worse. An ultrasound reveals a large ovarian mass and abdominal and pelvic CT reveals no metastases. Her serum levels of CA-125 are elevated and the biopsy reveals the primary neoplasm as ovarian in origin. Her cancer is characterized as invasive carcinoma without metastasis. Which of the following cellular changes is consistent with this diagnosis?", "answer": "Loss of E-cadherin", "options": {"A": "Appropriate basal to apical differentiation", "B": "Intact basement membrane", "C": "Loss of E-cadherin", "D": "Seeding via capillaries", "E": "Increased proliferation of cells with preservation of size and shape"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 36-year-old African American woman G1P0 at 33 weeks gestation presents to the emergency department because \"her water broke.\" Her prenatal history is remarkable for proteinuria in the absence of hypertension during her third trimester check-up. She denies any smoking, alcohol use, sick contacts, abdominal pain, fever, nausea, vomiting, or diarrhea. Her temperature is 98.6°F (37°C), blood pressure is 150/90 mmHg, pulse is 120/min, and respirations are 26/min. While the on-call obstetrician is on her way to the emergency department, the following labs are obtained:\n\nHemoglobin: 11 g/dL\nHematocrit: 35 %\nLeukocyte count: 9,800/mm^3 with normal differential\nPlatelet count: 400,000/mm^3\n\nSerum:\nNa+: 137 mEq/L\nCl-: 99 mEq/L\nK+: 3.9 mEq/L\nHCO3-: 22 mEq/L\nBUN: 35 mg/dL\nGlucose: 128 mg/dL\nCreatinine: 1.2 mg/dL\n\nUrine:\nEpithelial cells: Scant\nProtein: 2+\nGlucose: 1+\nWBC: 2/hpf\nBacterial: None\n\nWhat is the most likely finding in the neonate after delivery?", "answer": "Growth retardation", "options": {"A": "Growth retardation", "B": "Meconium aspiration", "C": "Microcephaly", "D": "Seizures", "E": "Stillbirth"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 30-year-old woman, gravida 2, para 1, at 40 weeks' gestation is admitted to the hospital in active labor. Her first pregnancy and delivery were complicated by iron deficiency anemia and pregnancy-induced hypertension. She has had no routine prenatal care during this pregnancy but was diagnosed with oligohydramnios 4 weeks ago. The remainder of her medical history is not immediately available. A 2400-g (5.4-lb) female newborn is delivered vaginally. Examination of the newborn shows a short, mildly webbed neck and low-set ears. Ocular hypertelorism along with slanted palpebral fissures are noted. A cleft palate and hypoplasia of the nails and distal phalanges are present. There is increased coarse hair on the body and face. Which of the following best explains the clinical findings found in this newborn?", "answer": "Maternal phenytoin therapy", "options": {"A": "Maternal phenytoin therapy", "B": "Fetal posterior urethral valves", "C": "Maternal diabetes mellitus", "D": "Maternal alcohol intake", "E": "Fetal X chromosome monosomy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old female presents to her obstetrician 3 weeks postpartum for failure to lactate. Of note, she has been unable to tolerate cold environments since the birth of her child. Review of systems is positive for fatigue, lightheadedness, and a 3-pound weight gain over the last 3 weeks. Her delivery was complicated by placenta accreta with postpartum blood loss. Her newborn infant is doing well on formula. She denies any personal or family history of thyroid disease. Physical exam is overall unremarkable. On a panel of hormone testing, which of the following levels is most likely to be normal in this patient?", "answer": "Aldosterone", "options": {"A": "Antidiuretic hormone", "B": "Aldosterone", "C": "Cortisol", "D": "Luteinizing hormone", "E": "Thyroid hormone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 44-year-old woman comes to the physician because of a 2-year history of progressive dysphagia. She initially had symptoms only when consuming solid foods, but for the past 2 months she has also had difficulty swallowing liquids. She describes a feeling of food “getting stuck” in her throat. She was diagnosed with gastroesophageal reflux disease 2 years ago and has had episodic pallor of her fingers since adolescence. She has smoked half a pack of cigarettes daily for 24 years. Her only medication is omeprazole. Her pulse is 65/min, respirations are 12/min, and blood pressure is 127/73 mm Hg. Examination shows thickening of the skin of her fingers, with small white papules on her fingertips. There are small dilated blood vessels on her face, lips, and tongue. Cardiopulmonary examination shows no abnormalities. Which of the following is the most likely cause of this patient's dysphagia?", "answer": "Esophageal smooth muscle atrophy and fibrosis", "options": {"A": "Uncoordinated contractions of the esophagus", "B": "Protrusion of thin tissue membranes into the esophagus", "C": "Esophageal smooth muscle atrophy and fibrosis", "D": "Degeneration of upper and lower motor neurons", "E": "Outpouching of the lower pharyngeal mucosa and submucosa\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 14-year-old boy is brought to the emergency department by his parents for joint pain following the acute onset of a diffuse, pruritic rash for the past 24 hours. A week ago, he was diagnosed with pharyngitis after returning home from summer camp and is currently taking antibiotics. There is no family history of serious illness. His temperature is 38.5°C (101.3°F), pulse is 90/min, and blood pressure is 110/70 mm Hg. Physical examination shows periorbital edema, generalized lymphadenopathy, and well-circumscribed, erythematous, confluent skin lesions of variable sizes up to several centimeters in width over his entire body. There is pain on passive movement of wrists and ankle joints bilaterally. Urine dipstick shows 1+ proteinuria. There is no hematuria. Which of the following is the most appropriate next step in management?", "answer": "Discontinue antibiotic", "options": {"A": "Switch medication to doxycycline", "B": "Discontinue antibiotic", "C": "Administer prednisone", "D": "Perform allergy testing", "E": "Administer diphenhydramine\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 61-year-old woman comes to the physician because of a 6-day history of cough, shortness of breath, and fever. She also reports that she has had 4 episodes of watery diarrhea per day for the last 3 days. She has chronic bronchitis. She has smoked one pack of cigarettes daily for the past 30 years. Her temperature is 39°C (102.2°F) and pulse is 65/min. Examination shows diffuse crackles over the left lower lung field. Laboratory studies show:\nHemoglobin 13.8 g/dL\nLeukocyte count 16,000/mm3\nPlatelet count 150,000/mm3\nSerum\nNa+ 131 mEq/L\nCl- 102 mEq/L\nK+ 4.7 mEq/L\nAn x-ray of the chest shows consolidation of the left lower lobe. A Gram stain of induced sputum shows numerous neutrophils but no organisms. Which of the following is the most appropriate pharmacotherapy?\"", "answer": "Levofloxacin", "options": {"A": "Rifampin", "B": "Amoxicillin", "C": "Vancomycin", "D": "Levofloxacin", "E": "Cotrimoxazole"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 70-year-old woman presents to the office for a yearly physical. She states she has recently started experiencing pain in her legs and her back. Last year, she experienced a fracture of her left arm while trying to lift groceries. The patient states that she does not consume any dairy and does not go outside often because of the pain in her legs and back. Of note, she takes carbamazepine for seizures. On exam, her vitals are within normal limits. You suspect the patient might have osteomalacia. Testing for which of the following is the next best step to confirm your suspicion?", "answer": "25-hydroxyvitamin D", "options": {"A": "7-dehydrocholesterol", "B": "25-hydroxyvitamin D", "C": "1,25-hydroxyvitamin D", "D": "Pre-vitamin D3", "E": "Dietary vitamin D2"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3-year-old boy is brought to the physician for evaluation of developmental delay. He could sit alone at 12 months and started walking with support at the age of 2 years. He can name only very few familiar objects and uses simple two-word sentences. He cannot stack more than 2 blocks. His parents report that he does not like playing with other children. He is at the 80th percentile for head circumference, 85th percentile for height, and 50th percentile for weight. He has a long and narrow face as well as large protruding ears. His thumbs can be passively flexed to the ipsilateral forearm. This patient is at increased risk of developing which of the following conditions?", "answer": "Mitral regurgitation", "options": {"A": "Acute myeloid leukemia", "B": "Aortic dissection", "C": "Type 2 diabetes mellitus", "D": "Hyperuricemia", "E": "Mitral regurgitation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old woman is brought to the emergency department because of a 1-day history of lower abdominal pain and vaginal bleeding. Her last menstrual period was 7 weeks ago. A urine pregnancy test is positive. A pelvic ultrasound shows a normal appearing uterus with an empty intrauterine cavity and a minimal amount of free pelvic fluid. Treatment with a drug is begun. Which of the following is the most likely effect of this drug?", "answer": "Increase in deoxyuridine monophosphate", "options": {"A": "Decrease in guanylate", "B": "Increase in thymidine monophosphate", "C": "Increase in deoxyuridine monophosphate", "D": "Decrease in phosphoribosyl pyrophosphate", "E": "Increase in tetrahydrofolate polyglutamate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 71-year-old man presents to the physician for a routine health-maintenance examination. He feels well; however, he is concerned about the need for prostate cancer screening. He has a 3-year history of benign prostatic hyperplasia. His symptoms of urinary hesitancy and terminal dribbling of urine are well controlled with tamsulosin and finasteride. He also had a percutaneous coronary angioplasty done 2 years ago following a diagnosis of unstable angina. His medication list also includes aspirin, atorvastatin, losartan, and nitroglycerin. His vital signs are within normal limits. He has never had a serum prostate-specific antigen (PSA) test or prostate ultrasonography. Which of the following is the most appropriate screening test for prostate cancer in this patient?", "answer": "No screening test is recommended", "options": {"A": "Prostate ultrasonography every year", "B": "Prostate ultrasonography every 5 years", "C": "Serum PSA every year", "D": "Serum PSA every 2-4 years", "E": "No screening test is recommended"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 47-year-old woman presents to the clinic complaining of difficulty swallowing that started 1 month ago. The patient also reports a weight loss of 10 lbs during this time, without a change in her appetite. She denies fatigue, cough, hoarseness, pain, or hemoptysis. The patient has a history of childhood lymphoma, which was treated with radiation. She takes no medications. She has smoked 1 pack of cigarettes per day since she was 25 years old. Her physical exam is notable for a palpable nodule on the right side of the thyroid. An ultrasound is performed, which confirms a 1.2 cm hyperechoic nodule in the right lobe. Thyroid function labs are drawn and shown below:\n\nSerum TSH: 0.2 mU/L\nSerum thyroxine (T4): 187 nmol/L\nSerum triiodothyronine (T3): 3.3 nmol/L\n\nWhich of the following is the next best step in management?", "answer": "Thyroid scintigraphy", "options": {"A": "Fine needle aspiration", "B": "Levothyroxine", "C": "Partial thyroidectomy", "D": "Radioactive iodine", "E": "Thyroid scintigraphy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-year-old boy is brought to the physician by his parents for the evaluation of an unusual cough, a raspy voice, and noisy breathing for the last 2 days. During this time, the symptoms have always occurred in the late evening. The parents also report that prior to the onset of these symptoms, their son had a low-grade fever and a runny nose for 2 days. He attends daycare. His immunizations are up-to-date. His temperature is 37.8°C (100°F) and respirations are 33/min. Physical examination shows supraclavicular retractions. There is a high-pitched breath sound on inspiration. Which of the following is the most likely location of the abnormality?", "answer": "Subglottic larynx", "options": {"A": "Bronchioles", "B": "Epiglottis", "C": "Supraglottic larynx", "D": "Subglottic larynx", "E": "Bronchi\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 9-year-old boy from Eritrea is admitted to the hospital for lethargy and increased work of breathing. He has had recurrent episodes of fever, shortness of breath, and fatigue in the past 3 years. His pulse is 132/min and blood pressure is 90/66 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 82%. Auscultation of the chest shows coarse crackles in both lungs and a diastolic murmur at the cardiac apex. Despite appropriate lifesaving measures, he dies. A photomicrograph of a section of myocardium obtained at autopsy is shown. Which of the following is the most likely underlying cause of this patient's cardiac disease?", "answer": "Type II hypersensitivity reaction", "options": {"A": "Amastigote infiltration", "B": "Beta-myosin heavy chain defect", "C": "Non-caseating granulomatous inflammation", "D": "Type II hypersensitivity reaction", "E": "Exotoxin-mediated myonecrosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old woman presents to her primary care physician with symptoms of heat intolerance, unintentional weight loss, feelings of anxiety, and excessive energy that hinder her from falling asleep at night. On physical exam, the patient is found to have mildly protuberant eyes bilaterally as well as discoloration and swelling of her shins. Which of the following lab results would most likely be present in this patient?", "answer": "Decreased serum TSH", "options": {"A": "Decreased anti-TSH antibodies", "B": "Decreased free T4", "C": "Decreased serum TSH", "D": "Increased anti-mitochondrial antibodies", "E": "Increased serum TSH"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old man presents with acute-onset right flank pain. He says that his symptoms began suddenly 6 hours ago and have not improved. He describes the pain as severe, colicky, and ‘coming in waves’. It is localized to the right flank and radiates to the groin. He says he has associated nausea. He denies any fever, chills, dysuria, or hematuria. His past medical history is significant for asymptomatic nephrolithiasis, diagnosed 9 months ago on an upright abdominal radiograph, which has not yet been treated. The patient’s vital signs include: temperature 37.0°C (98.6°F), blood pressure 145/90 mm Hg, pulse 119/min, and respiratory rate 21/min. On physical examination, the patient is constantly moving and writhing with pain. There is severe right costovertebral angle tenderness. The remainder of the physical examination is unremarkable. A urine dipstick shows 2+ blood. A noncontrast CT of the abdomen and pelvis reveals a 4-mm-diameter radiopaque stone at the right ureteropelvic junction. Several nonobstructing small-diameter stones are noted in the left kidney. Mild hydronephrosis of the right kidney is noted. Intravenous fluids are started and ondansetron is administered. Which of the following is the next best step in the management of this patient?", "answer": "Hydrocodone and indomethacin", "options": {"A": "Emergency percutaneous nephrostomy", "B": "Hydrocodone and indomethacin", "C": "24-hour urine chemistry", "D": "Lithotripsy", "E": "Potassium citrate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old man is brought to the emergency department by ambulance 1 hour after a motor vehicle accident. He did not require any circulatory resuscitation at the scene, but he was intubated because he was unresponsive. He has no history of serious illnesses. He is on mechanical ventilation with no sedation. His blood pressure is 121/62 mm Hg, the pulse is 68/min, and the temperature is 36.5°C (97.7°F). His Glasgow coma scale (GCS) is 3. Early laboratory studies show no abnormalities. A search of the state donor registry shows that he has registered as an organ donor. Which of the following is the most appropriate next step in evaluation?", "answer": "Evaluation of brainstem reflexes", "options": {"A": "Apnea test", "B": "Brain MRI", "C": "Cerebral angiography", "D": "Electroencephalography", "E": "Evaluation of brainstem reflexes"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 72-year-old woman with a medical history significant for chronic kidney disease stage 4, hypertension, and type 2 diabetes mellitus, presents to the office for a scheduled visit. During her last visit, the physician started discussing with her the possibility of starting her on dialysis for her chronic kidney disease. The patient has no complaints about her health and enjoys spending time with her family. At presentation, she is afebrile; the blood pressure is 139/89 mm Hg and the heart rate is 80/min. On physical examination, her pulses are bounding, the complexion is pale, she has a grade ⅙ holosystolic murmur, breath sounds remain clear, and 2+ pedal edema to the knee. The measurement of which of the following laboratory values is most appropriate to screen for renal osteodystrophy in this patient?", "answer": "Serum intact parathyroid hormone level", "options": {"A": "Erythrocyte sedimentation rate", "B": "Serum C-reactive protein level", "C": "Serum intact parathyroid hormone level", "D": "Serum thyroid-stimulating hormone level", "E": "Serum vitamin B-12 level"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 44-year-old woman presents to her physician’s office for weakness. She reports having some difficulty placing books on a high shelf and getting up from a seated position. She denies muscle pain or any new rashes. She has noticed a tremor that is worse with action and has been having trouble falling asleep and staying asleep. She has lost approximately 10 pounds unintentionally over the course of 2 months. Medical history is significant for type I diabetes mellitus managed with an insulin pump. Family history is notable for systemic lupus erythematosus in her mother and panic disorder in the father. Her temperature is 98.6°F (37 °C), blood pressure is 140/85 mmHg, pulse is 102/min, and respirations are 17/min. On physical exam, she is mildly diaphoretic and restless, she has notable lid retraction, and her hair is thin. She has 4/5 strength in the proximal upper and lower extremities. Biceps and patellar tendon reflexes are 3+. Which of the following laboratory findings are most likely present in this patient?", "answer": "Decreased thyroid-stimulating hormone", "options": {"A": "Anti-Mi-2 antibody positivity", "B": "Anti-nuclear antibody positivity", "C": "Decreased thyroid-stimulating hormone", "D": "Increased erythrocyte sedimentation rate", "E": "Normal laboratory results"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old college senior visits the university health clinic after vomiting large amounts of blood. He has been vomiting for the past 36 hours after celebrating his team’s win at the national hockey championship with his varsity friends while consuming copious amounts of alcohol. His personal medical history is unremarkable. His blood pressure is 129/89 mm Hg while supine and 100/70 mm Hg while standing. His pulse is 98/min, strong and regular, with an oxygen saturation of 98%. His body temperature is 36.5°C (97.7°F), while the rest of the physical exam is normal. Which of the following is associated with this patient’s condition?", "answer": "Esophageal tear", "options": {"A": "Portal hypertension", "B": "Esophageal perforation", "C": "Esophageal metaplasia", "D": "Output of the esophageal mucosa", "E": "Esophageal tear"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old G1P0 at 23 weeks of gestation presents to the ED for left flank pain migrating to the groin. The pain is sharp, causing her to have nausea and vomiting. She also endorses urinary frequency, but denies vaginal discharge. There have been no complications in her pregnancy thus far. Her abdominal exam is remarkable for left lower quadrant tenderness to palpation with pain radiating to the left groin, but no guarding. She also has tenderness to palpation of the left flank. Blood is visible on inspection of the perineal area.\n\nUrinalysis:\nUrine Color: Yellow\npH: 7.1\nSpecific gravity: 1.010\nBlood: 3+\nBilirubin: Negative\nGlucose: Negative\nKetones: Negative\nProtein: Negative\nNitrite: Negative\nLeukocyte esterase: Negative\nRed blood cells: 291 cells/ul\nWhite blood cells: 75 cells/ul\n\nWhich of the following is the next best step in management?", "answer": "Renal ultrasound", "options": {"A": "Renal radiograph", "B": "Intravenous pyelogram", "C": "Renal ultrasound", "D": "Noncontrast CT scan of abdomen and pelvis", "E": "Exploratory laparoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old female presents to her primary care physician concerned that she has contracted a sexually transmitted disease. She states that she is having severe pain whenever she urinates and seems to be urinating more frequently than normal. She reports that her symptoms started after she began having unprotected sexual intercourse with 1 partner earlier this week. The physician obtains a urinalysis which demonstrates the following, SG: 1.010, Leukocyte esterase: Positive, Nitrites: Positive, Protein: Trace, pH: 5.0, RBC: Negative. A urease test is performed which is negative. This patient has most likely been infected with which of the following organisms?", "answer": "Escherichia coli", "options": {"A": "Proteus mirabilis", "B": "Klebsiella pneumoniae", "C": "Escherichia coli", "D": "Staphylococcus saprophyticus", "E": "Enterobacter cloacae"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old woman comes to the emergency department because of severe pain around her right eye, blurred vision in the same eye, and a headache for the past 4 hours. She is nauseous but has not vomited. She can see colored bright circles when she looks at a light source. She is currently being treated for a urinary tract infection with trimethoprim-sulfamethoxazole. She appears uncomfortable. Vital signs are within normal limits. Examination shows visual acuity of 20/20 in the left eye and counting fingers at 5 feet in the right eye. The right eye shows conjunctival injection and edema of the cornea. The right pupil is dilated and fixed. Intravenous analgesia and antiemetics are administered. Which of the following is the most appropriate next step in management?", "answer": "Perform gonioscopy", "options": {"A": "Perform ultrasound biomicroscopy", "B": "Administer topical atropine", "C": "Perform gonioscopy", "D": "Perform fundoscopy", "E": "Administer topical steroids"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 48-year-old Caucasian woman presents to her physician for an initial visit. She has no chronic diseases. The past medical history is significant for myomectomy performed 10 years ago for a large uterine fibroid. She had 2 uncomplicated pregnancies and 2 spontaneous vaginal deliveries. Currently, she only takes oral contraceptives. She is a former smoker with a 3-pack-year history. Her last Pap test performed 2 years ago was negative. She had a normal blood glucose measurement 3 years ago. The family history is remarkable for systolic hypertension in her mother and older brother. The blood pressure is 110/80 mm Hg, heart rate is 76/min, respirations are 16/min, and oxygen saturation is 99% on room air. The patient is afebrile. The BMI is 32 kg/m2. Her physical examination is unremarkable. Which of the following preventative tests is indicated for this patient at this time?", "answer": "Fasting blood glucose", "options": {"A": "Abdominal ultrasound", "B": "Chest CT", "C": "Pap smear", "D": "Fasting blood glucose", "E": "Colonoscopy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying a strain of bacteria that retains a blue color after crystal violet dye and acetone are applied. The bacteria are inoculated in a petri dish containing hypotonic saline. After the addition of an antibiotic, the bacteria swell and rupture. This antibiotic most likely belongs to which of the following classes?", "answer": "Cephalosporin", "options": {"A": "Macrolide", "B": "Cephalosporin", "C": "Fluoroquinolone", "D": "Sulfonamide", "E": "Tetracycline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Immediately following prolonged delivery of the placenta at 40 weeks gestation, a 32-year-old multiparous woman develops vaginal bleeding. Other than mild asthma, the patient’s pregnancy has been uncomplicated. She has attended many prenatal appointments and followed the physician's advice about screening for diseases, laboratory testing, diet, and exercise. Previous pregnancies were uncomplicated. She has no history of a serious illness. She is currently on intravenous infusion of oxytocin. Her temperature is 37.2°C (99.0°F), blood pressure is 108/60 mm Hg, pulse is 88/min, and respirations are 17/min. Uterine palpation reveals a soft enlarged fundus that extends above the umbilicus. Based on the assessment of the birth canal and placenta, which of the following options is the most appropriate initial step in patient management?", "answer": "Uterine fundal massage", "options": {"A": "Discontinuing oxytocin", "B": "Intramuscular carboprost", "C": "Intravenous methylergonovine", "D": "Manual exploration of the uterus", "E": "Uterine fundal massage"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 17-year-old girl is brought to the physician because she has not had a menstrual period. There is no personal or family history of serious illness. Examination shows normal breast development. Pubic hair is coarse and extends to the inner surface of the thighs. Pelvic examination shows a blind vaginal pouch. Ultrasonography shows ovaries, but no uterus. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Müllerian duct agenesis", "options": {"A": "17-alpha-hydroxylase enzyme deficiency", "B": "Müllerian duct agenesis", "C": "Androgen insensitivity", "D": "Pure gonadal dysgenesis", "E": "Failure of Müllerian duct recanalization\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old man comes to the emergency department because of abdominal pain, a runny nose, and chills for 6 hours. He has also had diarrhea and difficulty sleeping. He appears irritable. His temperature is 37.1°C (98.8°F), pulse is 110/min, and blood pressure is 140/90 mm Hg. Examination shows cool, damp skin with piloerection. The pupils are 7 mm in diameter and equal in size. Cardiopulmonary examination shows no abnormalities. The abdomen is tender to palpation. Bowel sounds are hyperactive. Deep tendon reflexes are 3+ bilaterally. Withdrawal from which of the following substances is the most likely cause of this patient's symptoms?", "answer": "Heroin", "options": {"A": "Gamma-hydroxybutyric acid", "B": "Barbiturates", "C": "Cannabis", "D": "Phencyclidine", "E": "Heroin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 34-year-old G3P2 undergoes colposcopy at 15 weeks gestation due to high-grade intraepithelial lesion detected on a Pap smear. She has no history of the gynecologic disease and had normal Pap smear results prior to the current pregnancy. The pelvic examination does not reveal any cervical lesions. Colposcopy shows a non-deformed cervix with a well-visualized transformation zone. Application of acetic acid reveals an area of acetowhite epithelium 2 cm in the largest diameter located at 6 o’clock with sharp irregular borders. A punch biopsy shows irregularly shaped tongues of pleomorphic squamous epithelium cells invading the stroma to a depth of 2 mm. Which of the following describes the proper management strategy for this patient?", "answer": "Perform a diagnostic conization", "options": {"A": "Perform a diagnostic conization", "B": "Terminate the pregnancy and perform a radical hysterectomy", "C": "Observe until 34 weeks of pregnancy", "D": "Perform radical trachelectomy", "E": "Schedule a diagnostic lymphadenectomy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old G1P0 presents to her obstetrician at 26 weeks’ gestation complaining of worsening headaches and blurry vision. Her past medical history is notable for hypertension and diabetes mellitus. Her temperature is 98.6°F (37°C), blood pressure is 160/95 mmHg, pulse is 100/min, and respirations are 18/min. On physical exam, she is tender to palpation in her abdomen and has mild edema in her extremities. A urine dipstick demonstrates 3+ protein. The patient is immediately started on IV magnesium sulfate, diazepam, and a medication that affects both a- and ß-adrenergic receptors. Which of the following medications is most consistent with this mechanism of action?", "answer": "Labetalol", "options": {"A": "Labetalol", "B": "Propranolol", "C": "Metoprolol", "D": "Esmolol", "E": "Pindolol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman complains of intermittent fever and joint pain. She says that these symptoms have been present for the past month. Before that, she had no signs or symptoms and was completely healthy. She has also lost her appetite and some weight. A complete blood count (CBC) showed severe pancytopenia. What is the next best step in evaluating this patient?", "answer": "Bone marrow examination", "options": {"A": "Bone marrow examination", "B": "Treatment with antibiotics", "C": "Repeated CBCs for several weeks and reassess", "D": "Treatment with corticosteroids", "E": "Treatment for acute leukemia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 8-year-old boy presents to the emergency department with puffy eyes. The patient’s parents noticed that his eyes were very puffy this morning thus prompting his presentation. They state their son has always been very healthy and other than a rash acquired from wrestling treated with a topical antibiotic has been very healthy. His temperature is 98.3°F (36.8°C), blood pressure is 125/85 mmHg, pulse is 89/min, respirations are 18/min, and oxygen saturation is 99% on room air. Physical exam is notable for periorbital edema but is otherwise unremarkable. Urinalysis is notable for red blood cells and an amber urine sample. Which of the following is the most likely etiology of this patient’s symptoms?", "answer": "Deposition of circulating immune complexes", "options": {"A": "Autoimmune type IV collagen destruction", "B": "Deposition of circulating immune complexes", "C": "IgA-mediated vasculitis", "D": "IgE-mediated degranulation", "E": "Increased glomerular permeability to protein only"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 29-year-old woman, gravida 1, para 0, at 38 weeks' gestation comes to the emergency department for sudden leakage of clear fluid from her vagina. Her pregnancy has been uncomplicated. She has largely been compliant with her prenatal care but missed some appointments. She has a history of chronic hypertension. She drinks a glass of wine once per week. Current medications include labetalol, iron, and vitamin supplements. Her temperature is 37.9°C (100.2°F), pulse is 70/min, respirations are 18/min, and blood pressure is 128/82 mm Hg. Examination shows a soft and nontender abdomen on palpation. Speculum examination demonstrates clear fluid in the cervical canal. The fetal heart rate is reactive at 170/min with no decelerations. Tocometry shows no contractions. The vaginal fluid demonstrates a ferning pattern when placed onto a glass slide. Which of the following is the most likely cause of this patient's condition?", "answer": "Ascending infection", "options": {"A": "Ascending infection", "B": "Sexual intercourse during third trimester", "C": "β-blocker use", "D": "Alcohol use", "E": "Oligohydramnios"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 44-year-old man comes to his physician because of frequent urination and increased thirst for several weeks. Physical examination shows darkened skin and a firm mass in the right upper quadrant. His blood glucose is 220 mg/dL. A photomicrograph of a specimen obtained on liver biopsy is shown. Which of the following best describes the pathogenesis of the disease process in this patient?", "answer": "Defective transferrin receptor binding", "options": {"A": "Upregulation of erythropoietin production", "B": "Absence of β-globin synthesis", "C": "Absence of a serine protease inhibitor", "D": "Defective transferrin receptor binding", "E": "Defective serum copper transportation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old woman comes to the clinic for an annual well-check. Her past medical history includes diabetes and hypertension, which are well-controlled with metformin and losartan, respectively. The patient reports a healthy diet consisting of mainly vegetables and lean meat. She denies smoking or alcohol use. She enjoys taking walks with her husband and sunbathing. Physical examination is unremarkable expect for a rough, scaly, sand paper-like plaque on her left dorsal hand with no tenderness or pain. What is the most likely diagnosis?", "answer": "Actinic keratosis", "options": {"A": "Actinic keratosis", "B": "Psoriasis", "C": "Rosacea", "D": "Seborrheic keratosis", "E": "Sunburn"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man comes to the physician for a routine health maintenance examination. He feels well. His most recent examination 2 years ago included purified protein derivative (PPD) skin testing and showed no abnormalities. He is a retired physician and recently came back from rural China where he completed a voluntary service at a local healthcare center. A PPD skin test is performed. Three days later, an induration of 12 mm is noted. An x-ray of the chest shows no abnormalities. He is started on a drug that inhibits the synthesis of mycolic acid. This patient is at greatest risk of developing which of the following adverse effects?", "answer": "Liver injury", "options": {"A": "Optic neuropathy", "B": "Liver injury", "C": "Hyperuricemia", "D": "Cytochrome P-450 induction", "E": "Nephrotoxicity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 21-year-old gravida 1 presents to her physician’s office for an antepartum visit at 11 weeks gestation. She has complaints of malaise, occasional nausea, and changes in food preferences. Her vital signs include: blood pressure 100/70 mm Hg, heart rate 90/min, respiratory rate 14/min, and temperature 36.8℃ (98.2℉). Examination reveals a systolic ejection murmur along the left sternal border. There are no changes in skin color, nails, or hair growth. No neck enlargement is noted. Blood analysis shows the following:\nErythrocyte count 3.5 million/mm3\nHb 11.9 g/dL\nHCT 35%\nReticulocyte count 0.2%\nMCV 85 fL\nPlatelet count 21,0000/mm3\nLeukocyte count 7800/mm3\nSerum iron 17 µmol/L\nFerritin 120 µg/L\nWhat is the most likely cause of the changes in the patient’s blood count?", "answer": "Increase in plasma volume", "options": {"A": "Decreased iron transport across the intestinal wall", "B": "Increase in plasma volume", "C": "Failure of synthesis of a D-aminolevulinic acid", "D": "Insufficient iron intake", "E": "Failure of purine and thymidylate synthesis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "The study is performed in an attempt to determine whether there is an association between maternal exposure to 2nd-hand smoke and low birth weight. A total of 1,000 women who have given birth to at least 1 child are placed into 1 of 2 groups according to the birth weight of their 1st child. Each group includes 500 women whose 1st child either weighed < 2,500 g (5.5 lb) or > 2,500 g (5.5 lb). In the 1st group, 250 subjects admitted to living with or being in close proximity to a smoker. In the 2nd group, 50 subjects admitted to living with or being in close proximity to a smoker. Which of the following is the strongest measure of association that can be calculated from this study?", "answer": "Odds ratio", "options": {"A": "Odds ratio", "B": "Relative risk", "C": "Rate ratio", "D": "Absolute risk", "E": "Risk difference"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 50-year-old woman is brought to the emergency department following a motor vehicle accident. She is awake but slow to respond. Her breath smells of alcohol. The emergency medical technician reports that her blood pressure has been dropping despite intravenous fluids. Ultrasound reveals a hypoechoic rim around the spleen, suspicious for a splenic laceration. The patient is brought into the operating room for abdominal exploration and a splenic embolization is performed. Since arriving to the hospital, the patient has received 8 units of packed red blood cells and 2 units of fresh frozen plasma. She is stabilized and admitted for observation. The next morning on rounds, the patient complains of numbness and tingling of her mouth and cramping of her hands. Her temperature is 99°F (37.2°C), blood pressure is 110/69 mmHg, and pulse is 93/min. On physical examination, her abdomen is mildly tender without distention. The surgical wound is clean, dry, and intact. Jugular venous pressure is normal. Periodic spasms of the muscles of her bilateral upper and lower extremities can be seen and tapping of the facial nerve elicits twitching of he facial muscles. Which of the following is most likely to improve the patient’s symptoms?", "answer": "Calcium gluconate", "options": {"A": "Calcium gluconate", "B": "Dextrose", "C": "Lorazepam", "D": "Thiamine", "E": "Sodium bicarbonate"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 72-year-old man presents to the ED complaining of worsening abdominal pain over the last few hours. He also reports nausea, but denies fever, vomiting, or changes in the appearance of his bowel movements. His medical history is significant for type 2 diabetes mellitus, hypertension, coronary artery disease, stroke, atrial fibrillation, and peptic ulcer disease. Due to his recurrent bleeding peptic ulcers, he does not take warfarin. His surgical history is significant for an appendectomy as a child. His medications include metformin, lisinopril, metoprolol, and omeprazole. He has a 50-pack-year history of smoking. His temperature is 37.6 C (99.7 F), blood pressure is 146/80 mm Hg, pulse is 115/min, and respiratory rate is 20/min. On physical exam, he is in acute distress due to the pain. Pulmonary auscultation reveals scattered wheezes and decreased air entry. His heart rate is irregularly irregular, with no murmurs, rubs or gallops. Abdominal exam is significant for decreased bowel sounds and diffuse tenderness. Initial laboratory evaluation is as follows:\nNa 138 mEq/L, Cl 101 mEq/L, HCO3 12 mEq/L, BUN 21 mg/dL, Cr 0.9 mg/dL, glucose 190 mg/dL, amylase 240 U/L (normal < 65 U/L).\nWhat is the most likely diagnosis in this patient?", "answer": "Acute mesenteric ischemia", "options": {"A": "Peptic ulcer perforation", "B": "Acute cholecystitis", "C": "Acute mesenteric ischemia", "D": "Diabetic ketoacidosis", "E": "Acute pancreatitis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old multiparous woman comes to the physician for the evaluation of episodes of involuntary urine leakage for the past 6 months. She loses small amounts of urine without warning after laughing or sneezing. She also sometimes forgets the names of her grandchildren and friends. She is retired and lives at an assisted-living facility. She has insulin-dependent diabetes mellitus type 2. Her mother received a ventriculoperitoneal shunt around her age. She walks without any problems. Sensation to pinprick and light touch is normal. Which of the following is the primary underlying etiology for this patient's urinary incontinence?", "answer": "Urethral hypermobility", "options": {"A": "Detrusor-sphincter dyssynergia", "B": "Urethral hypermobility", "C": "Decreased cerebrospinal fluid absorption", "D": "Impaired detrusor contractility", "E": "Loss of sphincter control"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old woman presents to the office complaining of fatigue and unintentional weight loss. On examination, there is a palpable firm lymph node in the cervical area. Biopsy of the lymph node reveals Hodgkin’s lymphoma. The patient agrees to start the standard chemotherapy regimen. A few months later, after the completion of 3 successful courses, the patient presents with a dry cough and progressively worsening shortness of breath. Her temperature is 37°C (98.6°F), the blood pressure is 110/70 mm Hg, the pulse is 72/min, and the respirations are 16/min. Pulse oximetry shows an O2 saturation of 94% on room air. On spirometry, the patient's FEV1/FVC ratio is normal. Chest CT reveals bilateral diffuse cystic airspaces in middle and lower lung fields. Which of the following is the most likely cause of this patient’s current symptoms?", "answer": "Drug-induced interstitial lung disease", "options": {"A": "Drug-induced interstitial lung disease", "B": "Metastatic spread to the lungs", "C": "Development of chronic obstructive pulmonary disease", "D": "Transfusion-related acute lung injury", "E": "Development of bacterial pneumonia due to immunocompromised state"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old woman comes to the emergency department after coughing up 2 cups of bright red blood. A CT angiogram of the chest shows active extravasation from the right bronchial artery. A coil embolization is planned to stop the bleeding. During this procedure, a catheter is first inserted into the right femoral artery. Which of the following represents the correct subsequent order of the catheter route?", "answer": "Thoracic aorta, right posterior intercostal artery, right bronchial artery", "options": {"A": "Thoracic aorta, brachiocephalic trunk, right subclavian artery, right internal thoracic artery, right bronchial artery", "B": "Thoracic aorta, right subclavian artery, right internal thoracic artery, right bronchial artery", "C": "Thoracic aorta, right posterior intercostal artery, right bronchial artery", "D": "Thoracic aorta, right superior epigastric artery, right bronchial artery", "E": "Thoracic aorta, left ventricle, left atrium, pulmonary artery, right bronchial artery"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old farmer presents to the clinic for evaluation of a pigmented lesion on his arm. He states that he first noticed the lesion last year, but he believes that it has been slowly growing in size. He otherwise does not have any complaints and is generally healthy. Which of the following findings on physical exam would suggest a malignant diagnosis?", "answer": "Different pigmentation throughout the lesion", "options": {"A": "Different pigmentation throughout the lesion", "B": "Flat lesion with symmetric hyperpigmentation", "C": "Hyperpigmented lesion with smooth borders", "D": "Symmetrical ovoid lesion", "E": "Tenderness to palpation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 72-year-old man comes to the physician because of fatigue and a 5-kg (11-lb) weight loss over the past 6 months despite a good appetite. He takes no medications. He does not smoke or use illicit drugs. Physical examination shows hepatosplenomegaly and diffuse, nontender lymphadenopathy. Laboratory studies show a hemoglobin concentration of 11 g/dL and a leukocyte count of 16,000/mm3. A direct antiglobulin (Coombs) test is positive. A photomicrograph of a peripheral blood smear is shown. Which of the following is the most likely diagnosis?", "answer": "Chronic lymphocytic leukemia", "options": {"A": "Chronic myelogenous leukemia", "B": "Acute myelogenous leukemia", "C": "Follicular lymphoma", "D": "Chronic lymphocytic leukemia", "E": "Hemophagocytic lymphohistiocytosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-year-old adolescent presents to his pediatrician with progressive easy fatigability and exercises intolerance over the last several months. The patient was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. There is no history of palpitation, dyspnea, or lower limb edema. On physical examination his vital signs are stable. On chest auscultation, a wide fixed split in the second heart sound is detected. A medium-pitched systolic ejection murmur is present which is best heard at the left middle and upper sternal border. A short mid-diastolic rumble is also audible over the lower left sternal border, which is best heard with the bell of the stethoscope. Which of the following findings is most likely to be present on this patient’s echocardiogram?", "answer": "Anterior movement of ventricular septum during systole", "options": {"A": "Decreased right ventricular end-diastolic dimension", "B": "Anterior movement of ventricular septum during systole", "C": "Goose-neck deformity of left ventricular outflow tract", "D": "Increased left ventricular shortening fraction", "E": "Displacement of tricuspid valve leaflets inferiorly into right ventricle"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A one-week-old boy is brought to the emergency department by his mother, who recently immigrated to the United States and does not have health insurance. He was born at home, and has not received any medical care since birth. The mother states the boy has become irritable and has been feeding poorly. In the last day, she said he seems \"stiff\" and is having apparent muscle spasms. On your exam, you note the findings in figure A. Which of the following interventions might have prevented this disease?", "answer": "Toxoid vaccine given to mother pre-natally", "options": {"A": "Conjugated polysaccharide vaccine given to infant at birth", "B": "Toxoid vaccine given to mother pre-natally", "C": "Vitamin injection given to newborn at birth", "D": "Improved maternal nutrition", "E": "Genetic counseling"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Given the mRNA sequence shown below, if translation were to start at the first base, what would the tRNA anticodon be for the last amino acid translated in the chain?\n5'----GCACCGGCCUGACUAUAA---3'", "answer": "3' CGG 5'", "options": {"A": "3' GCG 5'", "B": "3' CGC 5'", "C": "3' GAU 5'", "D": "5' CGG 3'", "E": "3' CGG 5'"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 7-year-old boy is brought to a new pediatrician to establish care. He presents with a history of extensive eczema, recurrent respiratory, skin, and gastrointestinal infections, and significant thrombocytopenia. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Given this classic grouping of clinical symptoms in a patient of this age, which of the following represents the most likely underlying medical condition?", "answer": "Wiskott-Aldrich syndrome", "options": {"A": "Wiskott-Aldrich syndrome", "B": "Ataxia-telangiectasia", "C": "Severe combined immunodeficiency syndrome", "D": "Chediak-Higashi syndrome", "E": "Hyper-IgE disease"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 9-year-old boy is brought to the physician by his mother for evaluation of diffuse bone pain in his right leg. His family immigrated to the United States 6 months ago from northern Canada. He is below the 5th percentile for height and at the 10th percentile for weight. Physical examination shows tenderness to palpation of the right distal femur. There is hepatosplenomegaly. An x-ray of right femur shows generalized trabecular thinning and several osteolytic bone lesions. Laboratory studies show:\nHemoglobin 9.2 g/dL\nLeukocyte count 7,600/mm3\nPlatelets 71,000/mm3\nA bone marrow aspirate shows mononuclear cells filled with lipid that appear like wrinkled silk. Deficiency of which of the following enzymes is the most likely cause of this patient's symptoms?\"", "answer": "Glucocerebrosidase", "options": {"A": "Sphingomyelinase", "B": "α-Galactosidase A", "C": "Arylsulfatase A", "D": "Galactocerebrosidase", "E": "Glucocerebrosidase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man comes to the physician because of intermittent palpitations that occur when he is stressed, exercising, or when he drinks alcohol. Physical examination shows an irregularly irregular pulse. An ECG shows irregular QRS complexes without any discrete P waves. Pharmacotherapy with carvedilol is initiated for his condition. Compared to treatment with propranolol, which of the following adverse effects is most likely?", "answer": "Hypotension", "options": {"A": "Hyperkalemia", "B": "Hypotension", "C": "Bradycardia", "D": "Hyperglycemia", "E": "Bronchospasm"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "When hepatitis D was injected into an immunocompromised mouse, there was no detectable hepatitis D RNA in the blood at any time point during the next several months. When co-injected with hepatitis B, hepatitis D RNA was was detected in the blood. Which of the following best describes this phenomenon?", "answer": "Complementation", "options": {"A": "Recombination", "B": "Reassortment", "C": "Complementation", "D": "Phenotypic mixing", "E": "Transduction"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 33-year-old woman comes to the physician because of a 4-day history of fever, anterior neck pain, and throat swelling. She has no history of serious illness. Her temperature is 38.1°C (100.6°F) and pulse is 109/min. Physical examination shows diaphoresis and a fine tremor of the outstretched hands. The thyroid gland is enlarged, firm, and tender to palpation. Serum thyroid stimulating hormone level is 0.06 μU/mL and erythrocyte sedimentation rate is 65 mm/h. 123I scan shows an enlarged thyroid gland with diffusely decreased uptake. Histologic examination of a thyroid biopsy specimen is most likely to show which of the following findings?", "answer": "Noncaseating granulomas with multinucleated giant cells", "options": {"A": "Follicular epithelial cell hyperplasia", "B": "Undifferentiated giant cells with areas of necrosis and hemorrhage", "C": "Concentric intracellular lamellar calcifications", "D": "Lymphocytic infiltration with germinal follicle formation", "E": "Noncaseating granulomas with multinucleated giant cells"}, "meta_info": "step1", "answer_idx": "E"}
{"question": " A 43-year-old woman was admitted to the hospital for anticoagulation following a pulmonary embolism. She was found to have a deep venous thrombosis on further workup after a long plane ride coming back from visiting China. She denies any personal history of blood clots in her past, but she says that her mother has also had to be treated for pulmonary embolism in the recent past. Her past medical history is significant for preeclampsia, hypertension, polycystic ovarian syndrome, and hypercholesterolemia. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and she currently denies any illicit drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 111/min, and respiratory rate 23/min. On physical examination, her pulses are bounding and complexion is pale, but breath sounds remain clear. Oxygen saturation was initially 81% on room air, with a new oxygen requirement of 8 L by face mask. On day 6 of combined heparin and warfarin anticoagulation, her platelet count decreases from 182,000/mcL to 63,000/mcL. Her international normalized ratio (INR) is not yet therapeutic. What is the next best step in therapy?", "answer": "Discontinue heparin and warfarin", "options": {"A": "Continue heparin and warfarin until INR is therapeutic for 24 hours", "B": "Discontinue heparin; continue warfarin", "C": "Continue heparin; discontinue warfarin", "D": "Discontinue heparin and warfarin", "E": "Continue heparin and warfarin, and administer vitamin K"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 68-year-old woman is brought to the emergency department by ambulance after she was found down by her daughter. She lives alone in her apartment so it is unclear when she began to develop symptoms. Her medical history is significant for cardiac arrhythmias, diabetes, pericarditis, and a stroke 2 years ago. On presentation her temperature is 98.1°F (36.7°C), blood pressure is 88/51 mmHg, pulse is 137/min, and respirations are 18/min. On physical exam her skin is cold and clammy. If special tests were obtained, they would reveal dramatically decreased pulmonary capillary wedge pressure, increased systemic vascular resistance, and mildly decreased cardiac output. Which of the following treatments would most directly target the cause of this patient's low blood pressure?", "answer": "Intravenous fluids", "options": {"A": "Antibiotic administration", "B": "Intravenous fluids", "C": "Intravenous ionotropes", "D": "Relieve obstruction", "E": "Vasopressors"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 19-year-old woman presents to her gynecologist for evaluation of amenorrhea and occasional dull right-sided lower abdominal pain that radiates to the rectum. She had menarche at 11 years of age and had regular 28-day cycles by 13 years of age. She developed menstrual cycle irregularity approximately 2 years ago and has not had a menses for 6 months. She is not sexually active. She does not take any medications. Her weight is 94 kg (207.2 lb) and her height is 166 cm (5.4 ft). Her vital signs are within normal limits. The physical examination shows a normal hair growth pattern. No hair loss or acne are noted. There is black discoloration of the skin in the axillae and posterior neck. Palpation of the abdomen reveals slight tenderness in the right lower quadrant, but no masses are appreciated. The gynecologic examination reveals no abnormalities. The hymen is intact. The rectal examination reveals a non-tender, mobile, right-sided adnexal mass. Which of the following management plans would be best for this patient?", "answer": "A transvaginal ultrasound would provide a better resolution of the suspected pathology, but a transabdominal ultrasound can still be used to assess this patient", "options": {"A": "No imaging is indicated for this patient because the diagnosis can be made on the basis of the clinical examination", "B": "A transvaginal ultrasound would provide a better resolution of the suspected pathology, but a transabdominal ultrasound can still be used to assess this patient", "C": "Increased anterior abdominal wall adiposity does not pose any problems with a full urinary bladder, so a transabdominal ultrasound will provide the same sensitivity as a transvaginal ultrasound", "D": "Transabdominal ultrasound would be better for this patient because it can detect small pelvic masses better than a transvaginal ultrasound", "E": "Pelvic MRI is warranted in this case because transvaginal ultrasound cannot be performed and transabdominal ultrasound is unlikely to provide any diagnostic information"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old man comes to the physician for a follow-up examination. He was diagnosed with HIV infection 2 weeks ago. His CD4+ T-lymphocyte count is 162/mm3 (N ≥ 500). An interferon-gamma release assay is negative. Prophylactic treatment against which of the following pathogens is most appropriate at this time?", "answer": "Pneumocystis jirovecii", "options": {"A": "Aspergillus fumigatus", "B": "Mycobacterium tuberculosis", "C": "Pneumocystis jirovecii", "D": "Toxoplasma gondii", "E": "Cytomegalovirus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old department store manager comes to his doctor’s office complaining that he had recently been waking up in the middle of the night with abdominal pain. This has happened several nights a week in the past month. He has also been experiencing occasional discomfort in the afternoon. The patient's appetite has suffered as a result of the pain he was experiencing. His clothes hang on him loosely. The patient does not take any prescription or over the counter medications. The remainder of the patient’s history and physical exam is completely normal. The doctor refers the patient to a gastroenterologist for a stomach acid test and an upper gastrointestinal endoscopy which revealed that this patient is a heavy acid producer and has a gastric peptic ulcer. This ulcer is most likely found in which part of the stomach?", "answer": "In the pyloric channel within 3 cm of the pylorus", "options": {"A": "In the pyloric channel within 3 cm of the pylorus", "B": "Along the lesser curve at the incisura angularis", "C": "Proximal gastroesophageal ulcer near the gastroesophageal junction", "D": "In the body", "E": "Multiple sites throughout the stomach"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An otherwise healthy 49-year-old man presents to his primary care physician for follow-up for a high HbA1C. 3 months ago, his HbA1c was 8.9% on routine screening. Today, after lifestyle modifications, it is 8.1% and his serum glucose is 270 mg/dL. Which of the following is the best initial therapy for this patient's condition?", "answer": "Metformin", "options": {"A": "Metformin", "B": "Metformin added to basal insulin", "C": "Metformin added to an insulin secretagogue", "D": "Metformin added to a glucagon-like peptide 1 (GLP-1) agonist", "E": "Metformin added to a dipeptidyl peptidase-4 (DPP-4) inhibitor"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 9-year-old boy is brought to the physician by his parents because of right-sided shoulder pain for 1 day. He has not had chills or sweating. Over the past year, he was treated twice in the emergency department for painful swelling of his hands and feet. He emigrated with his family from Kenya 2 years ago. His temperature is 37.4°C (99.3°F), pulse is 96/min, and blood pressure is 123/82 mm Hg. Physical examination shows no tenderness, erythema, or joint swelling of the shoulder. Laboratory studies show:\nHemoglobin 7 g/dL\nMean corpuscular volume 88 μm\nReticulocyte count 9%\nLeukocyte count 12,000/mm3\nA peripheral blood smear is most likely to show which of the following abnormalities?\"", "answer": "Nuclear remnants in erythrocytes", "options": {"A": "Ring-shaped inclusions in erythrocytes", "B": "Teardrop-shaped erythrocytes", "C": "Nuclear remnants in erythrocytes", "D": "Fragmentation of erythrocytes", "E": "Erythrocytes with no central pallor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man with a history of coronary artery disease and hyperlipidemia presents to his internist for a follow-up visit 3 weeks after visiting an urgent care center for symptoms of cough, fever, and difficulty breathing. He had been prescribed erythromycin in addition to his usual regimen of rosuvastatin and aspirin. With which potential side effect or interaction should the internist be most concerned?", "answer": "Myalgia due to decreased rosuvastatin metabolism in the presence of erythromycin", "options": {"A": "Gastric bleeding due to decreased aspirin metabolism in the presence of erythromycin", "B": "Unstable angina due to decreased rosuvastatin metabolism in the presence of erythromycin", "C": "Myalgia due to decreased rosuvastatin metabolism in the presence of erythromycin", "D": "Metabolic acidosis due to decreased aspirin metabolism in the presence of erythromycin", "E": "Tinnitus due to decreased aspirin metabolism in the presence of erythromycin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 15-year-old girl is brought into her pediatrician's office by her mother because the mother thinks her daughter has attention issues. The mother explains that her daughter started high school four months ago and had lackluster grades in a recent progress report despite having earned consistent top marks in middle school. The mother complains that her daughter never talks to her at home anymore. The patient yells at her mother in the exam room, and the mother is escorted out of the room. The patient scoffs that her mother is so overbeaing, ruining her good days with criticism. She begins to chew gum and states that she hates hanging out with the girls on the cheerleading squad. She denies experiencing physical abuse from anyone or having a sexual partner. She has seen kids smoke marijuana underneath the football field bleachers, but does not go near them and denies smoking cigarettes. She denies any intention to harm herself or others, thinks her grades went down because her teachers are not as good as her middle school teachers, and states she thinks she learns best by watching explanations through online videos. What is the most likely diagnosis?", "answer": "Normal behavior", "options": {"A": "Oppositional defiant disorder", "B": "Normal behavior", "C": "Conduct disorder", "D": "Attention deficit hyperactivity disorder", "E": "Antisocial personality disorder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 47-year-old alcoholic man presents to the office for a 72-hour history of intense right hemithorax pain. He also complains of fever, chills, and sweating that started 10 days ago, as well as persistent coughing with abundant malodorous sputum. Chest radiography shows a round consolidation with hydro-aerial levels in the middle third of the right hemithorax. Sputum samples for a direct exam, culture, and bradykinin (BK) are sent. What is the correct diagnosis?", "answer": "Lung abscess", "options": {"A": "Bronchiectasis", "B": "Bronchopulmonary sequestration", "C": "Lung abscess", "D": "Tuberculosis", "E": "Lung cancer"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 9-year-old boy is brought to the clinic by his parents for an annual wellness examination. He is a relatively healthy boy who was born at term via vaginal delivery. He is meeting his developmental milestones and growth curves and is up-to-date on his immunizations. The father complains that he is picky with his food and would rather eat pizza. The patient denies any trouble at school, fevers, pain, or other concerns. A physical examination demonstrates a healthy boy with a grade 3 midsystolic ejection murmur at the second intercostal space that does not disappear when he sits up. What is the most likely explanation for this patient’s findings?", "answer": "Defect of the septum secundum", "options": {"A": "Defect of the septum secundum", "B": "Failure of the septum primum to fuse with the endocardial cushions", "C": "Inflammation of the visceral and parietal pericardium", "D": "Physiologic conditions outside the heart", "E": "Prolonged patency of the ductus arteriosus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman presents to the emergency department with palpitations for the last hour. This is her 3rd emergency department visit in the last 8 weeks due to the same complaint. She denies fever, shortness of breath, nasal discharge, bowel changes, weight loss, and heat intolerance. She has asthma that is poorly controlled despite regular inhaler use. She drinks a cup of coffee each morning, and she is physically active and jogs for at least 30 minutes daily. She is in a monogamous relationship with her boyfriend and regularly uses barrier contraceptives. Her last menses was 1 week ago. Physical examination reveals: blood pressure 104/70 mm Hg, pulse 194 /min that is regular, and respiratory rate 18/min. Her ECG is shown in the image. A gentle massage over the carotid artery for 5–10 seconds did not terminate her palpitations. What is the most appropriate next step in the management of this patient?", "answer": "Verapamil", "options": {"A": "Adenosine", "B": "Amiodarone", "C": "Digoxin", "D": "Propranolol", "E": "Verapamil"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "One day after a 4700-g (10-lb 6-oz) male newborn is delivered to a 28-year-old primigravid woman, he has bluish discoloration of his lips and fingernails. Oxygen saturation on room air is 81%. Examination shows central cyanosis. A continuous machine-like murmur is heard over the left upper sternal border. A single S2 heart sound is present. Supplemental oxygen does not improve cyanosis. Echocardiography shows the pulmonary artery arising from the posterior left ventricle and aorta arising from the right ventricle with active blood flow between the right and left ventricles. Further evaluation of the mother is most likely to show which of the following?", "answer": "Elevated fasting blood glucose", "options": {"A": "Prenatal lithium intake", "B": "Elevated serum TSH", "C": "Prenatal phenytoin intake", "D": "Positive rapid plasma reagin test", "E": "Elevated fasting blood glucose"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old boy with a history of severe, persistent asthma presents to the emergency department with severe shortness of breath and cough. He states that he was outside playing basketball with his friends, forgot to take his inhaler, and began to have severe difficulty breathing. On exam, he is in clear respiratory distress with decreased air movement throughout all lung fields. He is immediately treated with beta-agonists which markedly improve his symptoms. Prior to treatment, which of the following was most likely observed in this patient?", "answer": "Pulsus paradoxus", "options": {"A": "Inspiratory stridor", "B": "Increased breath sounds", "C": "Friction rub", "D": "Kussmaul's sign", "E": "Pulsus paradoxus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3670-g (8 lb 1 oz) male newborn is delivered to a 26-year-old primigravid woman. She received adequate prenatal care and labor was uncomplicated. She has chronic hepatitis B infection and gastroesophageal reflux disease. Her only medication is ranitidine. She admits to smoking cannabis and one half-pack of cigarettes daily. She drinks two beers on the weekend. The mother is apprehensive about taking care of her baby and requests for some information regarding breastfeeding. Which of the following is a contraindication to breastfeeding?", "answer": "Cannabis use", "options": {"A": "Ranitidine use", "B": "Hepatitis B infection", "C": "Seropositive for cytomegalovirus", "D": "Cannabis use", "E": "Smoking\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old male is picked up by paramedics presenting with respiratory depression, pupillary constriction, and seizures. Within a few minutes, the male dies. On autopsy, fresh tracks marks are seen on both arms. Administration of which of the following medications would have been appropriate for this patient?", "answer": "Naloxone", "options": {"A": "Methadone", "B": "Naloxone", "C": "Diazepam", "D": "Flumazenil", "E": "Buproprion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3900-g (8.6-lb) newborn is delivered at 38 week' gestation to a 27-year-old woman, gravida 3, para 2, via spontaneous vaginal delivery. Immediately after delivery, he spontaneously cries, grimaces, and moves all four extremities. Over the next five minutes, he becomes cyanotic, dyspneic, and tachypneic. Mask ventilation with 100% oxygen is begun, but ten minutes after delivery the baby continues to appear cyanotic. His temperature is 37.2°C (99.0°F), pulse is 155/min, respirations are 65/min, and blood pressure is 90/60 mm Hg. Pulse oximetry on 100% oxygen mask ventilation shows an oxygen saturation of 83%. Breath sounds are normal on the right and absent on the left. Heart sounds are best heard in the right midclavicular line. The abdomen appears concave. An x-ray of the chest is shown below. Which of the following is the most appropriate initial step in the management of this patient?", "answer": "Intubation and mechanical ventilation\n\"", "options": {"A": "Extracorporeal life support", "B": "Surfactant administration", "C": "Surgical repair", "D": "Chest tube placement", "E": "Intubation and mechanical ventilation\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 17-year-old boy is being seen by student health for a sports physical. He denies any recent injuries. He reports that he is doing well in his classes. He fractured his left collar bone 3 years ago, which required open reduction and internal fixation. He has not had any other surgeries. He takes no medications. His father and his paternal grandfather have hypertension. When asked about his mother, the patient tears up and he quickly begins talkig about how excited he is for baseball tryouts. He has a chance this year to be in the starting lineup if, “I just stay focused.” From previous records, the patient’s mother died of ovarian cancer 6 months ago. Which of the following defense mechanisms is the patient exhibiting?", "answer": "Suppression", "options": {"A": "Denial", "B": "Displacement", "C": "Rationalization", "D": "Repression", "E": "Suppression"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 5-year-old boy is brought to the emergency department by his parents with complaints of severe muscle cramping and abdominal pain. They live in Virginia. The parents state that about 2 hours before, the child was playing in their outdoor shed when he suddenly ran inside crying, saying he was bitten by a bug. One hour following the bite, the child developed the symptoms of cramping and pain. He has no known medical history and takes no medications. His blood pressure is 132/86 mm Hg, the heart rate is 116/min, and the respiratory rate is 20/min. Vital signs reveal tachycardia and hypertension. On exam, there is a 1 cm area of erythema to the dorsum of his right hand without any further dermatologic findings. Palpation of his abdomen reveals firm rigidity but no discernable rebound tenderness. What arthropod is most likely responsible for his symptoms?", "answer": "Black widow", "options": {"A": "Brown recluse", "B": "Black widow", "C": "Bark scorpion", "D": "Cryptopid centipede", "E": "Tick"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 59-year-old man presents to his primary care provider complaining of bilateral calf cramping with walking for the past 7 months. His pain goes away when he stops walking; however, his condition affects his work as a mail carrier. His medical history is remarkable for type 2 diabetes mellitus, hyperlipidemia, and 25-pack-year smoking history. His ankle-brachial index (ABI) is found to be 0.70. The patient is diagnosed with mild to moderate peripheral artery disease. A supervised exercise program for 3 months, aspirin, and cilostazol are started. Which of the following is the best next step if the patient has no improvement?", "answer": "Revascularization", "options": {"A": "Heparin", "B": "Pentoxifylline", "C": "Revascularization", "D": "Amputation", "E": "Surgical decompression"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 66-year-old female with hypertension and a recent history of acute ST-elevation myocardial infarction (STEMI) 6 days previous, treated with percutaneous transluminal angioplasty (PTA), presents with sudden onset chest pain, shortness of breath, diaphoresis, and syncope. Vitals are temperature 37°C (98.6°F), blood pressure 80/50 mm Hg, pulse 125/min, respirations 12/min, and oxygen saturation 92% on room air. On physical examination, the patient is pale and unresponsive. Cardiac exam reveals tachycardia and a pronounced holosystolic murmur loudest at the apex and radiates to the back. Lungs are clear to auscultation. Chest X-ray shows cardiomegaly with clear lung fields. ECG is significant for ST elevations in the precordial leads (V2-V4) and low-voltage QRS complexes. Emergency transthoracic echocardiography shows a left ventricular wall motion abnormality along with a significant pericardial effusion. The patient is intubated, and aggressive fluid resuscitation is initiated. What is the next best step in management?", "answer": "Immediate transfer to the operating room", "options": {"A": "Intra-aortic balloon counterpulsation", "B": "Administer dobutamine 70 mcg/min IV", "C": "Emergency pericardiocentesis", "D": "Immediate transfer to the operating room", "E": "Immediate cardiac catheterization"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought to the physician because of a 5-week history of pain in his left thigh. The mother reports that her son fell from a ladder while playing with friends about a month and a half ago. He had a runny nose 3 weeks ago. He has no history of serious illness. He has reached all developmental milestones for his age. His immunizations are up-to-date. His 7-year-old brother has asthma. He is at 60th percentile for height and 65th percentile for weight. He appears healthy. His temperature is 37.1°C (98.8°F), pulse is 88/min, respirations are 17/min, and blood pressure is 110/70 mm Hg. Examination shows a mild left-sided antalgic gait. The left groin is tender to palpation; abduction and internal rotation are limited by pain. The remainder of the physical examination shows no abnormalities. His hemoglobin concentration is 13.3 g/dL, leukocyte count is 8,800/mm3, and platelet count is 230,000/mm3. An x-ray of the pelvis shows a left femoral epiphysis that is smaller than the right with widening of the medial joint space on the left. The femoral head shows little discernible damage. Which of the following is the most appropriate next step in management?", "answer": "Limited weight bearing and physical therapy", "options": {"A": "Femoral osteotomy", "B": "Oral hydroxyurea", "C": "Casting and bracing", "D": "Femoral head pinning", "E": "Limited weight bearing and physical therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 69-year-old man presents for a general follow up appointment. He states that he is doing well and wants to be sure he is healthy. The patient’s past medical history is significant for type II diabetes mellitus, peripheral vascular disease, and hypertension. His current medications include metformin, glyburide, lisinopril, metoprolol and hydrochlorothiazide. His blood pressure is 130/90 mmHg and pulse is 80/min. A fasting lipid panel was performed last week demonstrating an LDL of 85 mg/dL and triglycerides of 160 mg/dL. The patient states that he has not experienced any symptoms since his last visit. The patient’s blood glucose at this visit is 100 mg/dL. Which of the following is recommended in this patient?", "answer": "Begin statin therapy", "options": {"A": "Increase lisinopril dose", "B": "Increase HCTZ dose", "C": "Increase metformin dose", "D": "Begin statin therapy", "E": "Discontinue metoprolol and start propranolol"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old man presents to the emergency department with loss of consciousness. The patient was brought in 20 minutes ago by the supervisor at a homeless shelter who found him passed out next to a bottle of acetaminophen. The patient has a past medical history of HIV, hepatitis C, IV drug abuse, alcohol abuse, suicide attempt, and constipation. He takes methadone daily but is notably non-compliant with his anti-retroviral therapy. His temperature is 104°F (40°C), blood pressure is 85/40 mmHg, pulse is 180/min, respirations are 18/min, and oxygen saturation is 90% on room air. The patient is started on IV fluids, N-acetylcysteine, and 100% oxygen. Blood cultures are obtained, and lab work is sent off. The patient is then started on broad spectrum antibiotics and given norepinephrine. Repeat vitals demonstrate hypotension and tachycardia. Serum toxicology returns and is positive for alcohol. The patient is transferred to the medicine floor and managed further. Two days later, the patient's vitals have improved. Repeat lab values are ordered and return as follows:\n\nHemoglobin: 11 g/dL\nHematocrit: 30%\nLeukocyte count: 6,500 cells/mm^3 with normal differential\nPlatelet count: 245,000/mm^3\n\nSerum:\nNa+: 138 mEq/L\nCl-: 100 mEq/L\nK+: 4.1 mEq/L\nHCO3-: 22 mEq/L\nBUN: 30 mg/dL\nGlucose: 145 mg/dL\nCreatinine: 1.4 mg/dL\nCa2+: 9.6 mg/dL\nAST: 1,440 U/L\nALT: 1,350 U/L\n\nWhich of the following is the best explanation for this patient’s laboratory abnormalities?", "answer": "Previous hypotension", "options": {"A": "Alcohol abuse", "B": "Antibiotic use", "C": "Chronic viral infection", "D": "Previous hypotension", "E": "Toxic liver metabolite"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A father brings his 1-year-old son into the pediatrician's office for a routine appointment. He states that his son is well but mentions that he has noticed an intermittent bulge on the right side of his son's groin whenever he cries or strains for bowel movement. Physical exam is unremarkable. The physician suspects a condition that may be caused by incomplete obliteration of the processus vaginalis. Which condition is caused by the same defective process?", "answer": "Hydrocele", "options": {"A": "Femoral hernia", "B": "Hydrocele", "C": "Varicocele", "D": "Diaphragmatic hernia", "E": "Testicular torsion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old man comes to the physician because of a 3-week history of rash that began on his right ankle and gradually progressed up his calf. The rash is itchy and mildly painful. He has type 2 diabetes mellitus and hypertension. He does not smoke or drink alcohol. His current medications include metformin, glipizide, and enalapril. He returned from a trip to Nigeria around 5 weeks ago. He works on a fishing trawler. His temperature is 37°C (98.6°F), pulse is 65/min, and blood pressure is 150/86 mm Hg. Other than the rash on his calf, the examination shows no abnormalities. A picture of the rash is shown. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Cutaneous larva migrans", "options": {"A": "Contact dermatitis", "B": "Cutaneous larva migrans", "C": "Tinea", "D": "Superficial thrombophlebitis", "E": "Swimmer's itch"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 64-year-old woman comes to the emergency room because of a sudden weakness in her right arm and leg. She has atrial fibrillation, tinea unguium, gastroesophageal reflux disease, hypertension, and hypercholesterolemia. Current medications include warfarin, enalapril, simvastatin, lansoprazole, hydrochlorothiazide, griseofulvin, and ginkgo biloba. Two weeks ago, she had an appointment with her podiatrist. Physical examination shows sagging of her right lower face and decreased muscle strength in her right upper and lower extremity. Babinski sign is positive on the right. Her prothrombin time is 14 seconds (INR = 1.5). Which of the following drugs is the most likely underlying cause of this patient's current condition?", "answer": "Griseofulvin", "options": {"A": "Ginkgo biloba", "B": "Simvastatin", "C": "Enalapril", "D": "Lansoprazole", "E": "Griseofulvin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 70-year-old man is accompanied by his wife to the primary care clinic for hand tremors. He states that he first noticed the tremor of his left hand 1 year ago. Since then, the tremor has been worsening and now he can hardly relax when trying to read. His wife says that she is also worried about his memory. She had to take over the finances several weeks ago after learning that he had forgotten to pay the bills for the past few months. The patient’s medical history is significant for hypertension. He takes aspirin and amlodipine. His mother had schizophrenia. The patient drinks 1-2 beers a night and is a former cigar smoker. On physical examination, he speaks softly and has reduced facial expressions. He has a resting tremor that is worse on the left, and he resists manipulation of his bilateral upper extremities. Which of the following is the most likely diagnosis?", "answer": "Parkinson disease", "options": {"A": "Essential tremor", "B": "Dementia with Lewy bodies", "C": "Parkinson disease", "D": "Progressive supranuclear palsy", "E": "Tardive dyskinesia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 69-year-old woman comes to the physician because of a 3-week history of headache and worsening vision. Ophthalmologic examination shows a visual acuity of 20/120 in the right eye and 20/80 in the left eye. Physical examination shows no other abnormalities. Laboratory studies show a hemoglobin of 14.2 g/dL and total serum calcium of 9.9 mg/dL. A photomicrograph of a peripheral blood smear is shown. Serum electrophoresis shows increased concentration of a pentameric immunoglobulin. Which of the following is the most likely diagnosis?", "answer": "Waldenstrom macroglobulinemia", "options": {"A": "Multiple myeloma", "B": "Hyper IgM syndrome", "C": "Essential thrombocythemia", "D": "Waldenstrom macroglobulinemia", "E": "Giant cell arteritis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old male bodybuilder presents to the emergency department with weakness of his right arm. The patient states he has experienced these symptoms for a few weeks; however, today his hand felt so weak he dropped his cup of tea. The patient has a past medical history of diabetes. He drinks 2-7 alcoholic drinks per day and has smoked 2 packs of cigarettes per day since he was 25. The patient admits to using anabolic steroids. He has lost 17 pounds since he last came to the emergency department 1 month ago. His temperature is 99.5°F (37.5°C), blood pressure is 177/108 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam reveals decreased sensation in the right arm and 2/5 strength in the right arm and 5/5 strength in in the left arm. The patient states that he is experiencing a dull aching and burning pain in his right arm during the exam. Which of the following is the most likely diagnosis?", "answer": "Apical lung tumor", "options": {"A": "Apical lung tumor", "B": "Brachial plexopathy", "C": "Cerebral infarction", "D": "Scalenus anticus syndrome", "E": "Subclavian steal syndrome"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman comes to the emergency department because of abdominal pain, fever, nausea, and vomiting for 12 hours. Her abdominal pain was initially dull and diffuse but has progressed to a sharp pain on the lower right side. Two years ago she had to undergo right salpingo-oophorectomy after an ectopic pregnancy. Her temperature is 38.7°C (101.7°F). Physical examination shows severe right lower quadrant tenderness with rebound tenderness; bowel sounds are decreased. Laboratory studies show leukocytosis with left shift. An abdominal CT scan shows a distended, edematous appendix. The patient is taken to the operating room for an appendectomy. During the surgery, the adhesions from the patient's previous surgery make it difficult for the resident physician to identify the appendix. Her attending mentions that she should use a certain structure for guidance to locate the appendix. The attending is most likely referring to which of the following structures?", "answer": "Teniae coli", "options": {"A": "Deep inguinal ring", "B": "Teniae coli", "C": "Ileocolic artery", "D": "Right ureter", "E": "Epiploic appendages"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man presents to the emergency department after a car accident. He was the front seat restrained driver in a head-on collision. He has no significant past medical history. The patient’s vitals are stabilized and he is ultimately discharged with his injuries appropriately treated. At the patient’s follow up primary care appointment, he complains of being unable to lift his left foot. He otherwise states that he feels well and is not in pain. His vitals are within normal limits. Physical exam is notable for 1/5 strength upon dorsiflexion of the patient’s left foot, and 5/5 plantarflexion of the same foot. Which of the following initial injuries most likely occurred in this patient?", "answer": "Fibular neck fracture", "options": {"A": "Calcaneal fracture", "B": "Distal femur fracture", "C": "Fibular neck fracture", "D": "Lisfranc fracture", "E": "Tibial plateau fracture"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old man with no significant past medical history is brought in by ambulance after a witnessed seizure at home. On physical exam, temperature is 102.3 deg F (39.1 deg C), blood pressure is 90/62 mmHg, pulse is 118/min, and respirations are 25/min. He is unable to touch his chin to his chest and spontaneously flexes his hips with passive neck flexion. Appropriate empiric treatment is begun. CT head is unremarkable, and a lumbar puncture sample is obtained. Gram stain of the cerebrospinal fluid (CSF) reveals gram-positive diplococci. Which of the following would you expect to see on CSF studies?", "answer": "Elevated opening pressure, elevated protein, low glucose", "options": {"A": "Elevated opening pressure, elevated protein, elevated glucose", "B": "Elevated opening pressure, elevated protein, normal glucose", "C": "Elevated opening pressure, elevated protein, low glucose", "D": "Normal opening pressure, elevated protein, normal glucose", "E": "Normal opening pressure, normal protein, normal glucose"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old G1P0 woman at 33 weeks gestation presents to the obstetrician for an episode of postcoital spotting. The patient’s pregnancy is complicated by diet-controlled gestational diabetes. She has no other medical conditions. She takes prenatal vitamins. She denies tobacco, alcohol, or recreational drug use. She is currently sexually active with her boyfriend of 1 year, but prior to her current relationship, she states she had multiple male partners. On physical examination, no vaginal bleeding is appreciated. The cervix is closed, and there is no leakage of fluid or contractions. Fetal movement is normal. Fundal height is 33 cm. Fetal pulse is 138/min. The patient’s temperature is 37.0 °C (98.6°F), blood pressure is 112/75 mm Hg, and pulse is 76/min. A urine dipstick is negative for glucose and protein. Chlamydia trachomatis nucleic acid amplification testing is positive. Which of the following is the mechanism behind the first-line treatment for this patient’s condition?", "answer": "Inhibits the 50S ribosome subunit", "options": {"A": "Disrupts peptidoglycan cross-linking", "B": "Inhibits DNA gyrase", "C": "Inhibits the 30S ribosome subunit", "D": "Inhibits the 50S ribosome subunit", "E": "Inhibits transpeptidase and cell wall synthesis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman comes to the physician because of a 2-day history of severe burning pain with urination, and urinary frequency. She has no history of serious illness. The patient and her husband are currently trying to conceive a child. Her only medication is a prenatal multivitamin. Her temperature is 36.5°C (97.7°F), pulse is 75/min, and blood pressure is 125/78 mm Hg. Examination shows mild tenderness to palpation over the suprapubic region. There is no costovertebral angle tenderness. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14.8 g/dL\nLeukocyte count 8,200/mm3\nPlatelet count 230,000/mm3\nUrine\npH 7\nWBC 52/hpf\nRBC 17/hpf\nProtein negative\nNitrites positive\nLeukocyte esterase positive\nA urine pregnancy test is negative. Which of the following is the most appropriate next step in management?\"", "answer": "Oral fosfomycin", "options": {"A": "Oral ciprofloxacin", "B": "Reassurance and follow-up in 2 weeks", "C": "Urinary catheterization", "D": "Oral fosfomycin", "E": "Urine culture\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 60-year-old man comes to the physician because of a 2-day history of blood in his urine, lower abdominal pain, and a burning sensation while micturating. Five months ago, he was diagnosed with high-grade non-Hodgkin lymphoma and a deep vein thrombosis of his right popliteal vein. His medications include polychemotherapy every 3 weeks and a daily subcutaneous dose of low molecular weight heparin. The last cycle of chemotherapy was 2 weeks ago. His temperature is 37°C (98.6°F), pulse is 94/min, and blood pressure is 110/76 mm Hg. Examination shows bilateral axillary and inguinal lymphadenopathy, hepatosplenomegaly, and mild suprapubic tenderness. Laboratory studies show:\nHemoglobin 10.2 g/dL\nLeukocytes 4,300/mm3\nPlatelet count 145,000/mm3\nPartial thromboplastin time 55 seconds\nProthrombin time 11 seconds (INR=1)\nUrine\nRBCs 50–55/hpf\nRBC casts negative\nWBCs 7/hpf\nEpithelial cells 5/hpf\nBacteria occasional\nAdministration of which of the following is most likely to have prevented this patient's current condition?\"", "answer": "Mercaptoethane sulfonate", "options": {"A": "Protamine sulfate", "B": "Mercaptoethane sulfonate", "C": "Palifermin", "D": "Ciprofloxacin", "E": "Dexrazoxane"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 47-year-old woman is upset with her neighbor for playing music too loudly late at night. Rather than confront her neighbor directly, the woman makes a habit of parking her car in a manner that makes it difficult for her neighbor to park in his spot. Which of the following defense mechanisms is this woman demonstrating?", "answer": "Passive aggression", "options": {"A": "Sublimation", "B": "Regression", "C": "Acting out", "D": "Displacement", "E": "Passive aggression"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 54-year-old man presents with feelings of sadness and low mood on most days of the week for the past month. He reports an inability to concentrate and also finds it hard to develop an interest in his daily activities. He goes on to tell his physician that he struggles to get sleep at night, and, in the morning, he doesn’t have the energy to get out of bed. He says he feels like a loser since he hasn’t accomplished all that he had set out to do and feels guilty for being unable to provide for his family. He says he doesn’t have the will to live anymore but denies any plans to commit suicide. Past medical history is significant for erectile dysfunction which was diagnosed about a year ago. Which of the following medications should be avoided in the treatment of this patient’s depression?", "answer": "Fluoxetine", "options": {"A": "Vortioxetine", "B": "Fluoxetine", "C": "Bupropion", "D": "Mirtazapine", "E": "Vilazodone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old woman residing at an iodine-deficient endemic area presents to the physician with a painless and gradually progressive anterior neck mass. She has occasional dysphagia, but has no history of prior head and neck irradiation. The examination shows a mass that moves with deglutition, suggesting a thyroid mass. An ultrasound of the neck reveals a 3 cm x 3 cm (1.2 in x 1.2 in) mass in the right thyroid lobe with punctate microcalcifications, hypoechogenicity, irregular margins, and enhanced vascularity. There is no cervical lymphadenopathy. Her serum TSH is 3.3 mU/L, serum T3 is 2.2 nmol/L, and serum T4 is 111 nmol/L. An FNAC of the nodule shows abundant follicular cells suspicious of follicular neoplasm. A right lobectomy with isthmectomy is performed. Which of the following histopathological finding is diagnostic?", "answer": "Follicular cells that lack nuclear atypia, with capsular and vascular invasion", "options": {"A": "Presence of Psammoma bodies", "B": "Well-differentiated follicular cells without vascular invasion", "C": "Follicular cells that lack nuclear atypia, with capsular and vascular invasion", "D": "Hyperplastic parafollicular C cells", "E": "Highly undifferentiated malignant cells with areas of necrosis and inflammation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 15-year-old girl is brought to the physician because she has not yet had her first menstrual period. She reports that she frequently experiences cramping and pain in her legs during school sports. The patient is at the 20th percentile for height and 50th percentile for weight. Her temperature is 37°C (98.6°F), pulse is 70/min, and blood pressure is 155/90 mm Hg. Examination shows a high-arched palate with maloccluded teeth and a low posterior hairline. The patient has a broad chest with widely spaced nipples. Pelvic examination shows normal external female genitalia. There is scant pubic hair. Without appropriate treatment, this patient is at the greatest risk of developing which of the following complications?", "answer": "Pathologic fractures", "options": {"A": "Obsessive-compulsive disorder", "B": "Pathologic fractures", "C": "Pulmonary stenosis", "D": "Severe acne", "E": "Ectopia lentis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man presents to the urgent clinic complaining of pain in his right foot. He reported that the pain is intense that he had to remove his shoe and sock, and rates the pain level as 6 out of 10. He does not report trauma or recent infection. The past medical history includes hypertension. The medications include hydrochlorothiazide, enalapril, and a daily multivitamin. The family history is noncontributory. He consumes alcohol in moderation. His diet mostly consists of red meat and white rice. The blood pressure is 137/85 mm Hg, heart rate is 74/min, respiratory rate is 12/min, and the temperature is 36.9°C (98.4°F). The physical examination demonstrates swelling, redness, and tenderness to palpation in the first metatarsophalangeal joint of his right foot. There are no skin lesions. The rest of the patient’s examination is normal. An arthrocentesis procedure is scheduled. Which of the following is the most likely pharmacological treatment for the presented patient?", "answer": "Diclofenac alone", "options": {"A": "Probenecid alone", "B": "Oral methylprednisolone and meloxicam", "C": "Allopurinol alone", "D": "Colchicine and celecoxib", "E": "Diclofenac alone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 37-year-old man presents to the emergency department for a persistent fever. The patient states he has felt unwell for the past week and has felt subjectively febrile. The patient has a past medical history of a suicide attempt and alcohol abuse. He is not currently taking any medications. The patient admits to using heroin and cocaine and drinking 5-8 alcoholic drinks per day. His temperature is 103°F (39.4°C), blood pressure is 92/59 mmHg, pulse is 110/min, respirations are 20/min, and oxygen saturation is 96% on room air. Cardiopulmonary exam is notable for a systolic murmur heard best along the left sternal border. Dermatologic exam reveals scarring in the antecubital fossa. Which of the following is the next best step in management?", "answer": "Blood cultures", "options": {"A": "Blood cultures", "B": "Chest radiograph", "C": "CT scan", "D": "Ultrasound", "E": "Vancomycin and gentamicin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 63-year-old man comes to the physician for evaluation of fever and a nonproductive cough for the past 2 weeks. During this period, he has also had fatigue, myalgia, and difficulty breathing. Five weeks ago, he underwent an aortic prosthetic valve replacement due to high-grade aortic stenosis. The patient has a history of hypertension, asthma, and type 2 diabetes mellitus. A colonoscopy 2 years ago was normal. The patient has smoked one pack of cigarettes daily for the past 40 years. He has never used illicit drugs. Current medications include aspirin, warfarin, lisinopril, metformin, inhaled albuterol, and a multivitamin. The patient appears lethargic. Temperature is 38.6°C (101.5°F), pulse is 105/min, and blood pressure is 140/60 mm Hg. Rales are heard on auscultation of the lungs. A grade 2/6, diastolic blowing murmur is heard over the left sternal border and radiates to the right sternal border. A photograph of his right index finger is shown. Laboratory studies show a leukocyte count of 13,800/mm3 and an erythrocyte sedimentation rate of 48 mm/h. Which of the following is the most likely causal organism?", "answer": "Staphylococcus epidermidis", "options": {"A": "Streptococcus gallolyticus", "B": "Staphylococcus epidermidis", "C": "Enterococcus faecalis", "D": "Viridans streptococci", "E": "Streptococcus pyogenes"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old man presents to his primary care provider complaining of insomnia. He describes 3 months of frequent nighttime awakenings and nightmares. Per chart review, he is a combat veteran and was on a military tour in Afghanistan 4 months ago when a car bomb exploded, injuring him and killing his friend; however, when the physician asks about this, the patient states that he “does not talk about that” and changes the subject. He reports anxiety, irritability and feeling detached from his friends and family, which he believes is harming his relationships. Physical exam reveals an overweight, anxious appearing man with normal vital signs and an exaggerated startle response. Which of the following medications might have helped prevent this patient’s current disorder?", "answer": "Propanolol", "options": {"A": "Buspirone", "B": "Prazosin", "C": "Propanolol", "D": "Sertraline", "E": "Zolpidem"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old man presents with fatigue and weight loss for the past 4 months. He feels tired all the time. He also no longer feels interested in his work. He says he has lost weight and says, \"I just don’t want to eat.\" No significant past medical history. No current medications. Physical examination is unremarkable. The patient is started on sertraline. He returns for follow-up after 2 weeks and says that he has been compliant with his medications. He says that he is now getting a full night’s sleep with no early morning awakenings. Despite regaining his appetite, he hasn’t regained any lost weight, and he still feels fatigued. He believes that the medication is not working well and asks to be started on something else. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Continue sertraline", "options": {"A": "Replace sertraline with fluoxetine", "B": "Discontinue sertraline", "C": "Continue sertraline", "D": "Add fluoxetine to sertraline", "E": "Add amitriptyline to sertraline"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old man presents to the physician with fever, cough, weakness, night sweats, and poor appetite for the past 6 months. Medical records suggest that he has lost 7.5 kg (16.5 lb) of weight during this period. There is no history of breathlessness, nasal discharge, nasal obstruction, palpitations, chest pain, or symptoms related to digestion. He was released from prison 9 months ago after serving a 2-year sentence. His temperature is 38.1°C (100.6°F), pulse is 84/min, respirations are 16/min, and blood pressure is 122/80 mm Hg. Physical examination shows hepatomegaly and generalized lymphadenopathy, and auscultation of the chest reveals diffuse crackles throughout the lung fields bilaterally. On direct ophthalmoscopy, three discrete, yellow-colored, 0.5 mm to 1.0 mm lesions with indistinct borders are seen in the posterior pole. A chest X-ray is shown in the image. Tuberculin skin test with purified protein derivative is negative. What is the most likely diagnosis?", "answer": "Tuberculosis", "options": {"A": "Sarcoidosis", "B": "Chronic histoplasmosis", "C": "Langerhans cell histiocytosis", "D": "Tuberculosis", "E": "Bronchoalveolar carcinoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old man seeks evaluation from his physician with concerns about his blood pressure. He was recently told at a local health fair that he has high blood pressure. He has not seen a physician since leaving college because he never felt the need for medical attention. Although he feels fine, he is concerned because his father had hypertension and died due to a heart attack at 61 years of age. He does not smoke cigarettes but drinks alcohol occasionally. The blood pressure is 150/90 mm Hg today. The physical examination is unremarkable. Labs are ordered and he is asked to monitor his blood pressure at home before the follow-up visit. Two weeks later, the blood pressure is 140/90 mm Hg. The blood pressure measurements at home ranged from 130/90 to 155/95 mm Hg. An electrocardiogram (ECG) is normal. Lab tests show the following:\nSerum glucose (fasting) 88 mg/dL\n    Serum electrolytes: \nSodium 142 mEq/L\nPotassium 3.9 mEq/L\nChloride 101 mEq/L\nSerum creatinine 0.8 mg/dL\nBlood urea nitrogen 10 mg/dL\nCholesterol, total 250 mEq/L\nHDL-cholesterol 35 mEq/L\nLDL-cholesterol 186 mg/dL\nTriglycerides 250 mg/dL\n    Urinalysis:  \nGlucose negative\nKetones negative\nLeucocytes negative\nNitrite negative\nRBC negative\nCasts negative\nRegular exercise and a 'heart healthy diet' are advised. He is started on lisinopril for hypertension. Which of the following medications should be added to this patient?", "answer": "Atorvastatin", "options": {"A": "Atorvastatin", "B": "Niacin", "C": "Gemfibrozil", "D": "Orlistat", "E": "Cholestyramine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 19-year-old woman comes to the physician for a routine examination. She has one sexual partner, with whom she had unprotected sexual intercourse 3 days ago. She does not desire a pregnancy and is interested in a reliable and long-term contraceptive method. She has read in detail about the reliability, adverse-effects, health risks, and effective duration of intrauterine devices (IUD) as a birth control method. She requests the physician to prescribe and place an IUD for her. The physician feels that providing contraception would be a violation of her religious beliefs. Which of the following responses by the physician is most appropriate?", "answer": "“I can understand your need for the IUD, but I cannot place it for you due to my religious beliefs. I would be happy to refer you to a colleague who could do it.”", "options": {"A": "“Prescribing any means of contraception is against my religious beliefs, but as a doctor, I am obliged to place the IUD for you.”", "B": "“I need to discuss this with my pastor before I decide whether to insert an IUD, as this is against my religious beliefs.”", "C": "“I can understand your need for the IUD, but I cannot place it for you due to my religious beliefs. I would be happy to refer you to a colleague who could do it.”", "D": "“I understand your concerns, but I cannot place the IUD for you due to my religious beliefs. I recommend you use condoms instead.", "E": "“First, I would like to perform an STD panel since you are sexually active.”"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old woman was found lying down and unresponsive by her parents 2 hours ago. She has no significant medical history. Two years ago, the woman discovered that her husband of 8 years was having an extramarital affair; this revelation subsequently resulted in a drawn-out divorce. After the separation, she moved back in with her parents, who note that she stays in her room, sleeps a lot, and rarely eats. A physical exam shows obtundation. Her temperature is 37.1ºC (98.7ºF), pulse is 110/min, respirations are 24/min, and blood pressure is 126/78 mm Hg. The patient’s admission labs are as follows:\nTSH  3.2 µU/mL\nMorning cortisol  8 µg/dL\nProlactin 15 ng/mL\nFSH 7 mIU/mL\nLH 6 mIU/mL\nGlucose 22 mg/dL\nC-peptide not detected\nBeta-hydroxybutyrate  ≤ 2.7 mmol/L\nWhich of the following is most true of the cell type that is likely involved in the production of the molecule causing this patient’s symptoms?", "answer": "Gram-negative enteric bacillus; catalase-positive, oxidase-negative, turns pink on MacConkey agar", "options": {"A": "Contains M3 receptors that stimulate Gq in response to parasympathetic innervation", "B": "Gram-negative enteric bacillus; catalase-positive, oxidase-negative, turns pink on MacConkey agar", "C": "Located in the periphery of islets of Langerhans", "D": "Located in zona fasciculata of the adrenal cortex", "E": "Gram-negative enteric bacillus; urease-positive, oxidase-positive, can be identified by silver stain"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old female is brought to the emergency department by her husband 1 hour after the onset of chest palpitations. Her symptoms began suddenly while she was drinking coffee and have persisted since then. She has not had shortness of breath, chest pain, dizziness, or loss of consciousness. She has experienced these palpitations before, but they typically resolve spontaneously within a few minutes. She has no history of serious illness and takes no medications. Her temperature is 36.8°C (98.2°F), pulse is 155/min, respirations are 18/min, and blood pressure is 130/82 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. Physical examination shows no abnormalities other than tachycardia. An ECG is shown. Repeated, forceful exhalation against a closed glottis while supine fails to relieve her symptoms. Which of the following is the most appropriate next step in management?", "answer": "Administer adenosine intravenously", "options": {"A": "Administer adenosine intravenously", "B": "Administer verapamil intravenously", "C": "Electrical cardioversion", "D": "Administer digoxin intravenously", "E": "Administer diltiazem intravenously"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-year-old boy is brought to the office by his mother with complaints of facial puffiness and smoky urine. The mother noticed puffiness on her son’s face a week ago, and it has been progressively worsening since then. She also states that her son had a sore throat 3 weeks ago. The patient does not have fever/chills, changes in urinary frequency, or abdominal discomfort. On physical examination, facial edema is noted. The vital signs include: blood pressure 145/85 mm Hg, pulse 96/min, temperature 36.7°C (98.1°F), and respiratory rate 20/min.\nA complete blood count report shows:\nHemoglobin 10.1 g/dL\nRBC 4.9 million cells/µL\nHematocrit 46%\nTotal leukocyte count 6,800 cells/µL\nNeutrophils 70%\nLymphocytes 26%\nMonocytes 3%\nEosinophil 1%\nBasophils 0%\nPlatelets 210,000 cells/µL\nESR 18 mm (1st hour)\nUrinalysis shows:\npH 6.4\nColor dark brown\nRBC plenty\nWBC 3–4/HPF\nProtein absent\nCast RBC and granular casts\nGlucose absent\nCrystal none\nKetone absent\nNitrite absent\nWhich of the following laboratory findings can be expected in this patient?", "answer": "Positive streptozyme test", "options": {"A": "Normal erythrocyte sedimentation rate", "B": "Decreased serum creatinine", "C": "Positive streptozyme test", "D": "Increased C3 level", "E": "Negative antistreptolysin O (ASO) titer"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old African American man presents to the office for a routine examination. He has no complaints at this time. Records show that his systolic blood pressure was in the 130–138 range and diastolic blood pressure in the 88–95 range despite counseling on lifestyle modification. He admits that he was not compliant with this advice. He takes no medications and works at home as a web designer. He does not drink alcohol but smokes marijuana on a weekly basis. Temperature is 37°C (98.6°F), blood pressure is 138/90 mm Hg, pulse is 76/min, and respirations are 12/min. BMI is 29.8 kg/m2. Physical examination is normal except for truncal obesity, with a waist circumference of 44 inches. Fasting laboratory results are as follows:\nBlood glucose 117 mg/dL\nTotal cholesterol 210 mg/dL\nLDL cholesterol  120 mg/dL\nHDL cholesterol  38 mg/dL\nTriglycerides  240 mg/dL\n Which of the following mechanisms contribute to this patient’s condition?", "answer": "Insulin receptor resistance", "options": {"A": "Granulomatous inflammation in medium-sized vessels", "B": "Autoimmune destruction of pancreatic beta cells", "C": "Insulin receptor resistance", "D": "LDL receptor gene mutation", "E": "Excessive cortisol secretion and activity"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old man is brought by his wife with a complaint of an ongoing progressive history of memory problems for 6 months. He is an accountant by profession. He has difficulty remembering things and events, which has affected his job. He began using a diary to aid with remembering his agenda. His wife also says that he has wet his pants multiple times in the past 2 months and he avoids going out. He has been smoking 1 pack of cigarettes daily for the past 20 years. His past medical history is unremarkable. The vital signs include: blood pressure of 134/76 mm Hg, a pulse of 70 per minute, and a temperature of 37.0°C (98.6°F). His mini-mental state examination (MMSE) result is 22/30. His extraocular movements are normal. The muscle tone and strength are normal in all 4 limbs. The sensory examination is unremarkable. He has an absent Romberg’s sign. He walks slowly, taking small steps, with feet wide apart as if his feet are stuck to the floor. The CT scan of the head is shown in the image. What is the most likely diagnosis of the patient?", "answer": "Normal-pressure hydrocephalus", "options": {"A": "Early-onset Alzheimer’s disease", "B": "Frontotemporal dementia", "C": "Normal-pressure hydrocephalus", "D": "Parkinson’s disease", "E": "Progressive supranuclear palsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 69-year-old man presents with granulomatosis with polyangiitis diagnosed about 8 months ago. He was treated appropriately and states that his symptoms are well controlled. He is presenting today for a general follow up visit. His temperature is 99.0°F (37.2°C), blood pressure is 184/104 mmHg, pulse is 88/min, respirations are 12/min, and oxygen saturation is 98% on room air. His physical examination is notable for the findings in Figures A and B. Which of the following would be found in this patient on serum laboratory studies?", "answer": "Hypokalemia and metabolic alkalosis", "options": {"A": "Hyperkalemia and metabolic acidosis", "B": "Hyperkalemia and metabolic alkalosis", "C": "Hypokalemia and metabolic acidosis", "D": "Hypokalemia and metabolic alkalosis", "E": "Hypokalemia and normal acid-base status"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man comes to the emergency department because of left-sided chest pain and difficulty breathing for the past 30 minutes. His pulse is 88/min. He is pale and anxious. Serum studies show increased cardiac enzymes. An ECG shows ST-elevations in leads I, aVL, and V5-V6. A percutaneous coronary intervention is performed. In order to localize the site of the lesion, the catheter must pass through which of the following structures?", "answer": "Left coronary artery → left circumflex artery", "options": {"A": "Left coronary artery → left circumflex artery", "B": "Right coronary artery → right marginal artery", "C": "Left coronary artery → posterior descending artery", "D": "Right coronary artery → posterior descending artery", "E": "Left coronary artery → left anterior descending artery"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman, gravida 1, para 0, at 20 weeks' gestation comes to the physician for genetic counseling. Her brother and maternal uncle both have anemia that worsens after taking certain medications. Based on the pedigree shown, what is the probability that her son will be affected by the disease?", "answer": "25%", "options": {"A": "25%", "B": "0%", "C": "100%", "D": "12.5%", "E": "50%\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 75-year-old woman with late-onset autoimmune diabetes mellitus, rheumatoid arthritis, coronary artery disease, and idiopathic pulmonary fibrosis presents to the ship medic with altered mental status. While on her current cruise to the Caribbean islands, she experienced nausea, vomiting, and diarrhea. She takes aspirin, simvastatin, low-dose prednisone, glargine, and aspart. She is allergic to amoxicillin and shellfish. She works as a greeter at a warehouse and smokes 5 packs/day. Her temperature is 100.5°F (38.1°C), blood pressure is 90/55 mmHg, pulse is 130/min, and respirations are 30/min. Her pupils are equal and reactive to light bilaterally. Her lungs are clear to auscultation bilaterally, but her breath has a fruity odor. She has an early systolic murmur best appreciated at the left upper sternal border. She has reproducible peri-umbilical tenderness. Which of the following will most likely be present in this patient?", "answer": "Respiratory alkalosis and anion-gap metabolic acidosis", "options": {"A": "Respiratory acidosis and contraction metabolic alkalosis", "B": "Respiratory alkalosis and non-contraction metabolic alkalosis", "C": "Respiratory alkalosis and anion-gap metabolic acidosis", "D": "Respiratory alkalosis and non anion-gap metabolic acidosis", "E": "Respiratory acidosis and anion-gap metabolic acidosis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 31-year-old man is referred to a neurologist due to his gradually increasing eccentric behavior and involuntary movements, especially the movements of his arms and hands. He also has difficulty with his short-term memory. Past medical history is otherwise noncontributory. His father had similar symptoms before he died but those symptoms started at the age of 33. His blood pressure is 125/92 mm Hg, pulse is 90/min, respiratory rate 12/min, and temperature is 36.6°C (97.9°F). Physical exam reveals involuntary writhing movements of hands, slow eye movements, and sporadic rigidity. The physician explains that this is an inherited disorder where the symptoms occur progressively at an earlier age than the parent and often with increased severity in the future generations. Which of the following is the most likely diagnosis of this patient?", "answer": "Huntington's disease", "options": {"A": "Huntington's disease", "B": "Friedreich ataxia", "C": "Myotonic dystrophy", "D": "Wilson's disease", "E": "Neurofibromatosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old man comes to the physician for evaluation prior to parathyroidectomy. A Tc99m-sestamibi scan shows two spots of increased uptake in the superior mediastinum. These spots represent structures that are most likely derived from which of the following embryological precursors?", "answer": "3rd branchial pouch", "options": {"A": "4th branchial pouch", "B": "3rd branchial pouch", "C": "2nd branchial arch", "D": "4th branchial arch", "E": "3rd branchial arch"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old obese man presents to his primary care provider for an annual physical. The patient states that he has noticed increased sleepiness during the day at work over the past 6 months in addition to difficulty concentrating and worsening memory. He denies recent weight loss, and is not sure if he snores because he sleeps by himself. His past medical history is significant for hypertension and type II diabetes. Vital signs are T 98.6 F, HR 75 bpm, BP 140/90 mm Hg, RR 18/min. Physical exam reveals a 350 pound man. Jugular venous distension is difficult to evaluate due to excess tissue in the neck. There is no peripheral edema. Lung exam is normal. Routine CBC shows WBC count of 5000 cells/ml, platelet count of 350,000/mcL, hemoglobin of 18 gm/dL, and hematocrit of 54%. What is the most likely cause of his abnormal lab results?", "answer": "Sleep apnea", "options": {"A": "Cor pulmonale", "B": "Malignancy", "C": "Diuretic overuse", "D": "JAK2 mutation", "E": "Sleep apnea"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A new assay for Lyme disease has been developed. While the assay has been tested extensively in Maine, a group of inventors are planning to test it in Southern California. In comparison to the assay's performance in Maine, testing the assay in Southern California would affect the performance of the assay in which of the following ways?", "answer": "Greater likelihood that an individual with a negative test will truly not have Lyme disease\n\"", "options": {"A": "Decrease negative likelihood ratio of the Lyme disease assay", "B": "Lower likelihood that a patient without Lyme disease truly has a negative test", "C": "Greater likelihood that an individual with a positive test will truly have Lyme disease", "D": "Decreased positive likelihood ratio of the Lyme disease assay", "E": "Greater likelihood that an individual with a negative test will truly not have Lyme disease\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 68-year-old male is brought to the emergency department by his wife. An hour earlier, he dropped to the floor and began to violently shake his extremities. He urinated on the carpet and seemed confused for several minutes after. He is now feeling better. He has never experienced an episode like this before, nor does he think anyone in his family has. He and his wife are concerned that he has unintentionally lost 22.6 kg (50 lb) in the past 6 months. He has also been experiencing chest pain and has coughed up blood on a few occasions. He has a 50-pack-year smoking history and quit 2 years ago. His temperature is 36.8°C (98.2°F), heart rate is 98/min, respiratory rate is 15/min, blood pressure is 100/75 mm Hg, and he is O2 saturation is 100% on room air. The physical exam, including a full neurologic and cardiac assessment, demonstrates no abnormal findings. Edema, ascites, and skin tenting are notably absent. A brain MRI does not indicate areas of infarction or metastatic lesions. ECG is normal. Urine toxicology screen is negative. EEG is pending. Laboratory findings are shown below:\nBUN 15 mg/dL N: 7 to 20 mg/dL\npCO2 40 mm Hg N: 35-45 mm Hg\nCreatinine 0.8 mg/dL N: 0.8 to 1.4 mg/dL\nGlucose 95 mg/dL N: 64 to 128 mg/dL\nSerum chloride 103 mmol/L N: 101 to 111 mmol/L\nSerum potassium 3.9 mEq/L N: 3.7 to 5.2 mEq/L\nSerum sodium 115 mEq/L N: 136 to 144 mEq/L\nTotal calcium 2.3 mmol/L N: 2-2.6 mmol/L\nMagnesium 1.7 mEq/L N: 1.5-2 mEq/L\nPhosphate 0.9 mmol/L N: 0.8-1.5 mmol/L\nHemoglobin 14 g/dL N: 13-17 g/dL (men), 12-15 g/dL (women)\nGlycosylated hemoglobin 5.5% N: 4%-6%\nTotal cholesterol 4 mmol/L N: 3-5.5 mmol/L\nBicarbonate (HCO3) 19 mmol/L N: 18-22 mmol/L\nWhat is indicated first?", "answer": "Hypertonic saline", "options": {"A": "Phenytoin", "B": "Valproic acid", "C": "Diazepam", "D": "Hypertonic saline", "E": "Chemotherapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "One day after undergoing an open colectomy, a 65-year-old man with colon cancer experiences shivers. The procedure was originally scheduled to be done laparoscopically, but it was converted because of persistent bleeding. Besides the conversion, the operation was uneventful. Five years ago, he underwent renal transplantation because of cystic disease and has been taking prednisolone since then. He has a history of allergy to sulfonamides. He appears acutely ill. His temperature is 39.2°C (102.5°F), pulse is 120/min, respirations are 23/min, and blood pressure is 90/62 mm Hg. Abdominal examination shows a midline incision extending from the xiphisternum to the pubic symphysis. There is a 5-cm (2-in) area of purplish discoloration near the margin of the incision in the lower abdomen. Palpation of the abdomen produces severe pain and crackling sounds are heard. Laboratory studies show:\nHemoglobin 12.5 g/dL\nLeukocyte count 18,600/mm3\nPlatelet count 228,000/mm3\nErythrocyte sedimentation rate 120 mm/h\nSerum\nNa+ 134 mEq/L\nK+ 3.5 mEq/L\nCl- 98 mEq/L\nHCO3- 22 mEq/L\nGlucose 200 mg/dL\nUrea nitrogen 60 mg/dL\nCreatinine 3.2 mg/dL\nCreatine kinase 750 U/L\nWhich of the following is the most appropriate next step in management?\"", "answer": "Surgical debridement", "options": {"A": "X-ray of the abdomen and pelvis", "B": "Vacuum-assisted wound closure device", "C": "Surgical debridement", "D": "CT scan of abdomen", "E": "Intravenous clindamycin therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought to the physician by his mother because of fever and left ear pain for the past 3 days. He has also been frequently rubbing his left ear since he woke up in the morning. He has a history of atopic dermatitis, and his mother is concerned that his symptoms may be caused by him itching at night. She says that he has not been having many flare-ups lately; the latest flare-up subsided in time for his second birthday party, which he celebrated at a swimming pool 1 week ago. Six months ago, he had an episode of urticaria following antibiotic treatment for pharyngitis. He takes no medications. His temperature is 38.5°C (101.3°F), pulse is 110/min, respirations are 25/min, and blood pressure is 90/50 mm Hg. Otoscopy shows an opaque, bulging tympanic membrane. Which of the following is the most appropriate next step in management?", "answer": "Oral azithromycin", "options": {"A": "Topical hydrocortisone and gentamicin eardrops", "B": "Oral azithromycin", "C": "Tympanostomy tube placement", "D": "Otic ofloxacin therapy", "E": "Tympanocentesis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 75-year-old Caucasian man presents to the emergency department with abdominal pain. The patient states he was at home eating dinner when he began to experience severe abdominal pain. The patient has a past medical history of diabetes, hypertension, and atherosclerosis. He lives at home alone, smokes cigarettes, and drinks 1 to 2 alcoholic drinks per day. The patient is given IV morphine and an ultrasound is obtained demonstrating a dilated abdominal aorta. The patient states that his father died of a similar finding and is concerned about his prognosis. Which of the following is the greatest risk factor for this patient's presentation?", "answer": "Cigarette smoking", "options": {"A": "Atherosclerosis", "B": "Caucasian race", "C": "Cigarette smoking", "D": "Family history", "E": "Male gender and age"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 74-year-old gentleman presents to his family practitioner with the complaint of an inability to open his left eye since this morning. He also complains of intermittent pain and numbness in his left arm that has been present for the last few days. He denies ocular pain, difficulty swallowing, fatigability, or diplopia. His symptoms remain constant without fluctuation. He has a history of diabetes mellitus type 2, hypertension, and hypercholesterolemia. Further history reveals that he has lost 5.4 kg (12 lb) of weight in the past 4 months. He is a chronic smoker with a 72 pack-year smoking history. His blood pressure is 142/76 mm Hg, the heart rate is 76/min, the respiratory rate is 12/min, the temperature is 36.8°C (98.4°F), and BMI is the 18.2 kg/m2. The patient is awake, alert, and oriented to person, place, and time. He has partial drooping of the left eyelid while the right eyelid appears normal. The left pupil is 1 mm and the right pupil is 3 mm in diameter. Extraocular muscle movements are normal. What additional clinical feature would most likely be present in this patient?", "answer": "Loss of hemifacial sweating", "options": {"A": "Facial asymmetry", "B": "Ipsilateral loss of touch sensations on the face", "C": "Loss of hemifacial sweating", "D": "Tongue deviation to the left side", "E": "Urinary retention"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 65-year-old female patient with a past medical history of diabetes mellitus and an allergy to penicillin develops an infected abscess positive for MRSA on the third day of her hospital stay. She is started on an IV infusion of vancomycin at a dose of 1000 mg every 12 hours. Vancomycin is eliminated by first-order kinetics and has a half life of 6 hours. The volume of distribution of vancomycin is 0.5 L/kg. Assuming no loading dose is given, how long will it take for the drug to reach 94% of its plasma steady state concentration?", "answer": "24 hours", "options": {"A": "6 hours", "B": "12 hours", "C": "18 hours", "D": "24 hours", "E": "30 hours"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man presents to his primary care physician with concerns about poor sleep quality. The patient states that he often has trouble falling asleep and that it is negatively affecting his studies. He is nervous that he is going to fail out of graduate school. He states that he recently performed poorly at a lab meeting where he had to present his research. This has been a recurrent issue for the patient any time he has had to present in front of groups. Additionally, the patient is concerned that his girlfriend is going to leave him and feels the relationship is failing. The patient has a past medical history of irritable bowel syndrome for which he takes fiber supplements. His temperature is 98.9°F (37.2°C), blood pressure is 117/68 mmHg, pulse is 80/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam is within normal limits. Which of the following is the best initial step in management?", "answer": "Cognitive behavioral therapy", "options": {"A": "Alprazolam during presentations", "B": "Cognitive behavioral therapy", "C": "Duloxetine", "D": "Fluoxetine", "E": "Propranolol during presentations"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 56-year-old woman presents to the emergency department with a 1-hour history of persistent nasal bleeding. The bleeding started spontaneously. The patient experienced a similar episode last year. Currently, she has hypertension and takes hydrochlorothiazide and losartan. She is anxious. Her blood pressure is 175/88 mm Hg. During the examination, the patient holds a blood-stained gauze against her right nostril. Upon removal of the gauze, blood slowly drips down from her right nostril. Examination of the left nostril reveals no abnormalities. Squeezing the nostrils for 20 minutes fails to control bleeding. Which of the following interventions is the most appropriate next step in the management of this patient?", "answer": "Nasal oxymetazoline", "options": {"A": "Anterior nasal packing with topical antibiotics", "B": "Intravenous infusion of nitroglycerin", "C": "Nasal oxymetazoline", "D": "Oral captopril", "E": "Silver nitrate cauterization of the bleeding vessel"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A professional musician visits his physician after a morning concert. He complains of painless swelling in his right cheek when he plays his tuba. Physical examination of the patient reveals slight facial asymmetry due to minor swelling on the right side of the face. The skin over the swelling is smooth without any secondary changes. Palpation reveals a soft and non-tender swelling. The oral opening is normal without any trismus. Further examination reveals swelling of the left buccal mucosa extending from the first to the third molar. Bedside ultrasound shows small areas of high echogenicity consistent with pneumoparotid. Which nerve is associated with motor function to prevent air from entering the affected duct in this patient?", "answer": "CN VII – Buccal branch", "options": {"A": "V2 – Maxillary nerve", "B": "V3 – Mandibular nerve", "C": "CN VII – Zygomatic branch", "D": "CN VII – Buccal branch", "E": "CN VII – Marginal mandibular branch"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old man comes to the emergency department for evaluation of progressively worsening edema and decreased urine output over the past few days. He has a history of chronic sinus infections and was hospitalized last year for a suspected pneumonia with hemoptysis. Physical exam shows bilateral pitting edema of the lower extremities. Serum studies show a creatinine of 3.4 mg/dL and blood urea nitrogen of 35 mg/dL. Urine dipstick shows 3+ blood. A kidney biopsy is performed and light microscopy shows crescent-shaped glomeruli. Immunofluorescent microscopy of the tissue sample is most likely to show which of the following findings?", "answer": "No deposits", "options": {"A": "Subendothelial deposits", "B": "Intramembranous deposits", "C": "Mesangial deposits", "D": "Subepithelial deposits", "E": "No deposits"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 51-year-old man alcoholic presents to the emergency department with persistent vomiting. He was found vomiting forcefully next to an empty bottle of vodka. His medical history is significant for Lyme disease, currently being treated with doxycycline. After a prolonged episode of retching, the patient begins choking and coughing forcefully in between bouts of chest pain in the ER. At this point, the patient is unable to communicate. The patient appears toxic. His temperature is 37°C (98.6°F), respiratory rate is 15/min, pulse is 107/min, and blood pressure is 90/68 mm Hg. A quick physical exam reveals fullness at the base of the neck and a crunching, rasping sound on auscultation of the chest. The attending physician orders an upright chest X-ray, showing free mediastinal air. What is the most likely diagnosis?", "answer": "Boerhaave syndrome", "options": {"A": "Esophageal candidiasis", "B": "Dieulafoy's lesion", "C": "Pill esophagitis", "D": "Boerhaave syndrome", "E": "Mallory Weiss tear"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 85-year-old woman presents to her physician with complaints of significant weakness and weight loss. She recently has been diagnosed with stage IV breast cancer for which she currently is receiving treatment. She mentions that, despite taking a diet rich in protein and calories, she continues to lose weight. On physical examination, her vital signs are stable, but muscle wasting is clearly evident in her upper limbs, lower limbs, and face. The physician explains to her that her advanced cancer is the most important cause for the weight loss and muscle wasting. This cachexia is mediated by the proteolysis-inducing factor released from cancer cells. Which of the following effects is produced by this factor?", "answer": "Activation of NF-κB", "options": {"A": "Activation of hormone-sensitive lipase in adipose tissue", "B": "Increased release of tumor necrosis factor (TNF) from macrophages", "C": "Stimulation of apoptosis", "D": "Activation of NF-κB", "E": "Suppression of the appetite center in the hypothalamus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 74-year-old man is brought to the emergency department because of lower abdominal pain for 3 hours. The pain is sharp, constant, and does not radiate. He has not urinated for 24 hours and he has not passed stool for over 3 days. He was diagnosed with herpes zoster 3 weeks ago and has been taking amitriptyline for post-herpetic neuralgia for 1 week. Last year he was diagnosed with nephrolithiasis and was treated with lithotripsy. He has a history of hypertension, benign prostatic hyperplasia, and coronary artery disease. His other medications include amlodipine, metoprolol, tamsulosin, aspirin, and simvastatin. He appears uncomfortable. His temperature is 37.3°C (99.1°F), pulse is 102/min, and blood pressure is 140/90 mm Hg. Abdominal examination shows a palpable lower midline abdominal mass that is tender to palpation. Bowel sounds are hypoactive. The remainder of the examination shows no abnormalities. A pelvic ultrasound shows an anechoic mass in the lower abdomen. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Transurethral catheterization", "options": {"A": "CT scan of the abdomen and pelvis", "B": "Observation and NSAIDs administration", "C": "Transurethral catheterization", "D": "Finasteride administration", "E": "IV pyelography"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 57-year-old man presents with a large wound on his right lower leg that has been present for 6 months as shown in the picture. He has had chronically swollen legs for over 10 years. His mother and brother had similar problems with their legs. He had a documented deep vein thrombosis (DVT) in the affected leg 5 years earlier, but has no other past medical history. He has a blood pressure of 126/84 and heart rate of 62/min. Which of the following is the most likely diagnosis?", "answer": "Chronic venous insufficiency", "options": {"A": "Arterial ulcer", "B": "Marjolin ulcer", "C": "Chronic venous insufficiency", "D": "Lymphedema", "E": "Kaposi sarcoma"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 15-year-old girl is brought into the clinic for a second opinion by her mother. She was recently diagnosed with alopecia areata after having presented to her family doctor with a 2-month history of noticeable bald patches. The mother was concerned because the treatment involved topical steroids. The patient is noted to have started high school earlier this year and has an attention-deficit/ hyperactivity disorder that is treated with methylphenidate. The patient is afebrile and her vital signs are within normal limits. Physical examination reveals a moderately distressed young female playing with her hair. She has very short nails on both hands and patches of hair loss on the scalp. Which of the following is the most appropriate initial management for this patient’s condition?", "answer": "Behavioral therapy", "options": {"A": "Behavioral therapy", "B": "Selective serotonin reuptake inhibitors", "C": "Antipsychotics", "D": "Lithium", "E": "Psychodynamic therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Seven hours after undergoing left hip arthroplasty for chronic hip pain, a 67-year-old woman reports a prickling sensation in her left anteromedial thigh and lower leg. Neurologic examination shows left leg strength 3/5 on hip flexion and 2/5 on knee extension. Patellar reflex is decreased on the left. Sensation to pinprick and light touch are decreased on the anteromedial left thigh as well as medial lower leg. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Femoral nerve injury", "options": {"A": "Sural nerve injury", "B": "Femoral nerve injury", "C": "Fibular nerve injury", "D": "S1 radiculopathy", "E": "L5 radiculopathy\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old man comes to the physician because of a 3-month history of worsening exertional dyspnea and a persistent dry cough. For 37 years he has worked in a naval shipyard. He has smoked 1 pack of cigarettes daily for the past 40 years. Pulmonary examination shows fine bibasilar end-expiratory crackles. An x-ray of the chest shows diffuse bilateral infiltrates predominantly in the lower lobes and pleural reticulonodular opacities. A CT scan of the chest shows pleural plaques and subpleural linear opacities. The patient is most likely to develop which of the following conditions?", "answer": "Bronchogenic carcinoma", "options": {"A": "Bronchogenic carcinoma", "B": "Aspergilloma", "C": "Mycobacterial Infection", "D": "Malignant mesothelioma", "E": "Spontaneous pneumothorax"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 28-year-old woman comes to the physician because of lower abdominal pain and purulent vaginal discharge for the past 5 days. Menses occur at irregular 20 to 40-day intervals and last 4 to 8 days. She is sexually active with a new partner that she met 2 months ago and they use condoms inconsistently. She had a normal pap smear 5 months ago. She drinks 2 beers every other day. Her temperature is 39°C (102.2°F), pulse is 85/min, and blood pressure is 108/75 mm Hg. Examination shows lower abdominal tenderness and bilateral inguinal lymphadenopathy. Pelvic examination is notable for uterine and adnexal tenderness as well as small amounts of bloody cervical discharge. A spot urine pregnancy test is negative. Laboratory studies show a leukocyte count of 14,500/mm3 and an erythrocyte sedimentation rate of 90 mm/h. Nucleic acid amplification confirms the suspected diagnosis. The patient is started on ceftriaxone and doxycycline. Which of the following is the most appropriate next step in management?", "answer": "HIV test", "options": {"A": "CT scan of the abdomen", "B": "Tzanck smear", "C": "Colposcopy", "D": "Pap smear", "E": "HIV test"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Scientists are developing a new non-steroidal anti-inflammatory drug for osteoarthritis. Their hope is that the new drug will have a higher potency but the same efficacy as ibuprofen in the hope of minimizing gastrointestinal side effects. If ibuprofen is curve C in the figure provided, which of the following would be the curve for the new drug based on the scientists’ specifications? The desired therapeutic effect in patients is represented by the dashed line Y.", "answer": "Curve A", "options": {"A": "Curve A", "B": "Curve B", "C": "Curve C", "D": "Curve D", "E": "Curve E"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old man presents to the emergency department with shortness of breath. He reports that 6 months ago he was able to walk several miles without stopping. Yesterday, he became short of breath walking from his bed to the bathroom. He also endorses worsening abdominal distension and leg swelling, which he reports is new from several months ago. The patient has a past medical history of hypertension and hyperlipidemia. On physical exam, the patient has moderate abdominal distension and pitting edema to the knee. Crackles are present at the bilateral bases. Laboratory testing reveals the following:\n\nHemoglobin: 13.4 g/dL\nMean corpuscular volume (MCV): 102 um^3\nLeukocyte count: 11,200 /mm^3 with normal differential\nPlatelet count: 256,000/mm^3\n\nSerum:\nNa+: 137 mEq/L\nCl-: 100 mEq/L\nK+: 4.2 mEq/L\nHCO3-: 25 mEq/L\nBUN: 18 mg/dL\nGlucose: 126 mg/dL\nCreatinine: 0.9 mg/dL\nAlkaline phosphatase: 88 U/L\nAspartate aminotransferase (AST): 212 U/L\nAlanine aminotransferase (ALT): 104 U/L\n\nWhich of the following is the best next step in management?", "answer": "Alcohol cessation", "options": {"A": "Alcohol cessation", "B": "Antiviral therapy", "C": "Hormone replacement", "D": "Immunosuppressive therapy", "E": "Vitamin repletion"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old patient comes to the physician’s office with complaints of headaches and difficulty seeing out of the corner of her eye. She gave birth to her son 1 year ago. Further visual testing reveals the patient has bitemporal hemianopsia. The patient undergoes brain MRI which shows an anterior pituitary mass, likely adenoma. The patient has her blood tested to see if the adenoma is secreting extra hormone. The patient is found to have a slight excess of a hormone that uptakes a basophilic stain. Which of the following is most likely to be the hormone detected in her blood?", "answer": "Thyroid stimulating hormone", "options": {"A": "Prolactin", "B": "Oxytocin", "C": "Growth hormone", "D": "Antidiuretic hormone", "E": "Thyroid stimulating hormone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Several weeks following a kidney transplantation, a 50-year-old Caucasian female presents for evaluation of the transplanted organ. Biopsy shows inflammation involving the endothelial cells of the kidney vasculature and the presence of mononuclear cells in the interstitium. Which cells are most likely responsible for this presentation?", "answer": "Recipient T-cells", "options": {"A": "Donor T-cells", "B": "Recipient T-cells", "C": "Preformed recipient antibodies", "D": "Donor antibodies", "E": "Deposition of antibody immune complexes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 64-year-old woman comes to the physician for her routine health maintenance examination. She feels well. She had cervical cancer and received radiotherapy 8 years ago. Her vital signs are within normal limits. On percussion, the spleen size is 15 cm. Otherwise, the physical examination shows no abnormalities. The laboratory test results are as follows:\nHemoglobin 10 g/dL\nMean corpuscular volume 88 μm3\nLeukocyte count 65,000/mm3\nPlatelet count 500,000/mm3\nTwo images of the peripheral blood smear are shown on the image. Which of the following is the most appropriate next step in management?", "answer": "Dasatinib", "options": {"A": "Allogeneic stem cell transplantation", "B": "Dasatinib", "C": "Phlebotomy", "D": "Rituximab", "E": "Watchful waiting"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 17-year-old boy is brought to the emergency department after being stabbed with a knife during an altercation. Physical examination shows a 4-cm stab wound on the right lateral border of the T1 spinous process. An MRI of the spinal cord shows damage to the area of the right lateral corticospinal tract at the level of T1. Further evaluation will most likely show which of the following findings?", "answer": "Absence of right-sided motor function below T1", "options": {"A": "Absence of left-sided proprioception below T1", "B": "Absence of right-sided temperature sensation below T1", "C": "Presence of left-sided Babinski sign", "D": "Absence of left-sided fine touch sensation below T1", "E": "Absence of right-sided motor function below T1"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old man with type 1 diabetes mellitus is brought to the emergency department because of weakness, abdominal pain, nausea, and one episode of vomiting for 1 day. He has not taken his insulin for 3 days. His pulse is 125/min and respirations are 29/min. Examination shows dry mucous membranes. His breath has a fruity odor. Which of the following sets of laboratory values is most likely on evaluation of urine obtained before treatment?\n $$$ pH %%% HCO3- %%% NH4+ %%% K+ $$$", "answer": "↓ ↓ ↑ ↑", "options": {"A": "↓ ↓ ↑ ↑", "B": "↓ normal ↓ ↓", "C": "↓ ↑ normal ↑", "D": "↑ ↑ normal ↑", "E": "↓ ↓ ↑ ↓"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A group of researchers is looking to study the effect of body weight on blood pressure in the elderly. Previous work measuring body weight and blood pressure at 2-time points in a large group of healthy individuals revealed that a 10% increase in body weight was accompanied by a 7 mm Hg increase in blood pressure. If the researchers want to determine if there is a linear relationship between body weight and blood pressure in a subgroup of elderly individuals in this study, which of the following statistical methods would best be employed to answer this question?", "answer": "Pearson’s correlation", "options": {"A": "One-way analysis of variance (ANOVA)", "B": "Two-way analysis of variance (ANOVA)", "C": "Pearson’s correlation", "D": "Spearman’s correlation", "E": "Wilcoxon signed-rank test"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 80-year-old man is brought to the emergency department with complaints that he \"can’t control his left leg”. His symptoms started a few hours ago. He was outside taking a walk with his wife when suddenly his leg shot out and kicked her. His past medical history is notable for diabetes, hypertension, and a myocardial infarction 5 years ago. He smokes 1-2 cigarettes/day. He does not use alcohol or illicit drugs. On exam, the patient has intermittent wide, flinging movements that affect his proximal left arm. Which of the following parts of his brain is most likely damaged?", "answer": "Right subthalamic nucleus", "options": {"A": "Left internal capsule", "B": "Right internal capsule", "C": "Left subthalamic nucleus", "D": "Right subthalamic nucleus", "E": "Ventral posterior thalamic nucleus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old college student presents with his parents for a follow-up appointment. He was recently diagnosed with schizophrenia and was started on risperidone approx. 2 months ago. He reports a significant improvement since the start of treatment. His parents report that their son’s symptoms of delusions, hallucinations, and paranoid behavior have been ameliorated. On physical examination, the patient seems uncomfortable. He frequently fidgets and repeatedly crosses and uncrosses his legs. When asked if something is troubling him, he gets up and starts pacing. He says, “It’s always like this. I cannot sit still. It is frustrating.” What is the most likely diagnosis?", "answer": "Akathisia", "options": {"A": "Ataxia", "B": "Akathisia", "C": "Generalized anxiety disorder", "D": "Restless legs syndrome", "E": "Tardive dyskinesia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 53-year-old woman with type 2 diabetes mellitus is admitted for evaluation of recurrent episodes of nausea, tremors, and excessive sweating. She works as a nurse and reports self-measured blood glucose levels below 50 mg/dL on several occasions. Her family history is positive for borderline personality disorder. The only medication listed in her history is metformin. Which of the following is the most appropriate next step in management?", "answer": "Ask the patient if she is taking any medications other than metformin", "options": {"A": "Report the patient to her employer", "B": "Ask the patient if she is taking any medications other than metformin", "C": "Search the patient's belongings for insulin", "D": "Measure glycated hemoglobin concentration", "E": "Measure serum C-peptide concentration"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year old Caucasian female presents with symptoms of Graves' disease. Her doctor prescribes medications and sends the patient home. After two months of therapy, the patient returns upset that her exophthalmos has not gone away. Which of the following drugs should the physician have prescribed to treat the exophthalmos?", "answer": "Corticosteroids", "options": {"A": "Propanolol", "B": "Metropolol", "C": "PTU", "D": "Corticosteroids", "E": "No treatment as this will resolve naturally"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old woman is brought to the emergency department because of intermittent sharp right upper quadrant abdominal pain and nausea for the past 10 hours. She vomited three times. There is no associated fever, chills, diarrhea, or urinary symptoms. She has two children who both attend high school. She appears uncomfortable. She is 165 cm (5 ft 5 in) tall and weighs 86 kg (190 lb); BMI is 32 kg/m2. Her temperature is 37°C (98.6°F), pulse is 100/min, and blood pressure is 140/90 mm Hg. She has mild scleral icterus. The abdomen is soft and nondistended, with tenderness to palpation of the right upper quadrant without guarding or rebound. Bowel sounds are normal. Laboratory studies show:\nHemoglobin count 14 g/dL\nLeukocyte count 9,000 mm3\nPlatelet count 160,000 mm3\nSerum\nAlkaline phosphatase 238 U/L\nAspartate aminotransferase 60 U/L\nBilirubin\nTotal 2.8 mg/dL\nDirect 2.1 mg/dL\nWhich of the following is the most appropriate next step in diagnosis?\"", "answer": "Transabdominal ultrasonography", "options": {"A": "CT scan of the abdomen", "B": "Transabdominal ultrasonography", "C": "Endoscopic retrograde cholangiopancreatography", "D": "HIDA scan of the biliary tract", "E": "Upper gastrointestinal series"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-month-old girl is brought to her pediatrician for a checkup and vaccines. The patient’s mother wants to send her to daycare but is worried about exposure to unvaccinated children and other potential sources of infection. The toddler was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines. She does not walk yet but stands in place and can say a few words. The toddler drinks formula and eats a mixture of soft vegetables and pureed meals. She has no current medications. On physical exam, the vital signs include: temperature 37.0°C (98.6°F), blood pressure 95/50 mm Hg, pulse 130/min, and respiratory rate 28/min. The patient is alert and responsive. The remainder of the exam is unremarkable. Which of the following is most appropriate for this patient at this visit?", "answer": "MMR vaccine", "options": {"A": "Referral for speech pathology", "B": "MMR vaccine", "C": "Rotavirus vaccine", "D": "Meningococcal vaccine", "E": "Gross motor workup and evaluation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old patient is referred to an ophthalmologist because he has noticed some mild discomfort in his eyes though his vision remains unchanged. He cannot recall when this feeling started. His past medical history is significant for diabetes mellitus and two myocardial infarctions that have led to significant cardiac dysfunction. Specifically, he has dyspnea and peripheral edema and occasionally decompensates into more severe pulmonary edema requiring hospitalization. Testing reveals increased intra-ocular pressure so the ophthalmologist prescribes several medications. The medication for this disorder that is most likely to be contraindicated in this patient has which of the following characteristics?", "answer": "It decreases intracellular cyclic AMP levels", "options": {"A": "It alters bicarbonate metabolism", "B": "It decreases intracellular cyclic AMP levels", "C": "It increases intracellular calcium levels", "D": "It increases adenylyl cyclase activity", "E": "It is produced by cyclooxygenase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A baby is born after the 32nd gestational week by cesarean delivery. The mother suffered from gestational diabetes; however, she had no other pregnancy-related diseases and was otherwise healthy. The baby has a blood pressure of 100/58 mm Hg, heart rate of 104/min, and oxygen saturation of 88%. The child has tachypnea, subcostal and intercostal retractions, nasal flaring, and cyanosis. The cyanosis is responding well to initial administration of oxygen. The nasogastric tube was positioned without problems. Which of the following is the most likely diagnosis?", "answer": "Neonatal respiratory distress syndrome (NRDS)", "options": {"A": "Neonatal respiratory distress syndrome (NRDS)", "B": "Sepsis", "C": "Tracheoesophageal fistula", "D": "Pneumonia", "E": "Congenital heart anomaly with right-to-left shunt"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Eight days after sigmoid resection for acute diverticulitis, a 61-year-old man has left-sided flank pain. He has been on bowel rest since admission. Other than multiple admissions for alcohol withdrawal, he has no history of serious illness. Current medications include intravenous cefepime and morphine. His temperature is 36.9°C (98.4°F), pulse is 89/min, and blood pressure is 118/75 mm Hg. Abdominal exam shows a well-healing incision with minimal serous drainage. Examination of the skin shows scattered spider angiomas, a large hematoma on the left flank, and numerous bruises over the abdomen and extremities. He complains of pain when his left hip is extended. Laboratory studies show:\nHemoglobin 8.4 g/dL\nMean corpuscular volume 102 μm3\nLeukocyte count 8,200/mm3\nPlatelet count 170,000/mm3\nSerum\nBleeding time 4 minutes\nProthrombin time 26 seconds\nPartial thromboplastin time (activated) 39 seconds\nWhich of the following is the most likely underlying cause of this patient's current symptoms?\"", "answer": "Impaired activation of factor VII", "options": {"A": "Resistance of Factor V inactivation", "B": "Impaired activation of factor VII", "C": "Administration of heparin", "D": "Decreased synthesis of thrombopoietin", "E": "Deficiency of folic acid"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An otherwise healthy 14-year-old girl is brought to the emergency room by her father because of excessive thirst, excessive urination, and weight loss. Her symptoms started acutely 5 days ago. Vital signs reveal a temperature of 36.6°C (97.8°F), blood pressure of 100/65 mm Hg, and pulse of 105/min. Physical examination shows a thin girl with dry mucous membranes but normal skin turgor. Laboratory results are shown:\nRandom blood sugar 410 mg/dL\nC-peptide     undetectable\nSerum beta-hydroxybutyrate negative\nWhich of the following is the best initial therapy for this patient?", "answer": "Basal-bolus insulin", "options": {"A": "Metformin", "B": "Glimepiride", "C": "Intravenous fluids, insulin infusion, and correction of electrolytes", "D": "Basal-bolus insulin", "E": "Pramlintide"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year old boy is brought to the emergency department because he has been lethargic and has had several episodes of nausea and vomiting for the past day. He has also had increased thirst over the past two months. He has lost 5.4 kg (11.9 lbs) during this time. He is otherwise healthy and has no history of serious illness. His temperature is 37.5 °C (99.5 °F), blood pressure is 95/68 mm Hg, pulse is 110/min, and respirations are 30/min. He is somnolent and slightly confused. His mucous membranes are dry. Laboratory studies show:\nHemoglobin 16.2 g/dL\nLeukocyte count 9,500/mm3\nPlatelet count 380,000/mm3\nSerum\nNa+ 130 mEq/L\nK+ 5.5 mEq/L\nCl- 99 mEq/L\nHCO3- 16 mEq/L\nCreatinine 1.2 mg/dL\nGlucose 570 mg/dL\nKetones positive\nBlood gases, arterial\npH 7.25\npCO2 21 mm Hg\nWhich of the following is the most appropriate next step in management?\"", "answer": "Intravenous hydration with 0.9% normal saline and insulin", "options": {"A": "Intravenous hydration with 0.9% normal saline and insulin", "B": "Intravenous hydration with 5% dextrose solution and 0.45% normal saline", "C": "Intravenous hydration with 0.45% normal saline and insulin", "D": "Intravenous hydration with 0.9% normal saline and potassium chloride", "E": "Intravenous sodium bicarbonate\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old woman presents with a history of repeated episodes of discoloration of the fingers over the last 3 years. She mentions that the episodes are usually triggered by exposure to cold, which leads to a sequential white, blue, and red discoloration of her fingers, followed by resolution of the symptoms. During an episode, she experiences pain and numbness in the affected fingers. The episodes are usually of short duration and do not interfere with her life, so she did not seek medical advice till now. Which of the following additional clinical features in this patient would most likely support the most likely diagnosis?", "answer": "Bilateral symmetrical involvement of the extremities", "options": {"A": "Calcinosis on the dorsal surface of the forearm", "B": "Generalized pruritus", "C": "Photosensitive skin rash", "D": "Telangiectasia over face", "E": "Bilateral symmetrical involvement of the extremities"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-month-old boy is brought to the physician by his parents for a well-child examination. He has cystic fibrosis diagnosed by newborn screening. His parents report frequent feedings and large-volume and greasy stools. His 4-year-old brother has autism. Current medications include bronchodilators, pancreatic enzyme supplements, and fat-soluble vitamins. He is at the 18th percentile for height and 15th percentile for weight. Scattered wheezes are heard throughout both lung fields. Examination shows a distended and tympanic abdomen with no tenderness or guarding. Which of the following is a contraindication for administering one or more routine vaccinations in this patient at this time?", "answer": "History of intussusception", "options": {"A": "Fever of 38.2°C (100.7°F) following previous vaccinations", "B": "History of cystic fibrosis", "C": "Allergy to egg protein", "D": "History of febrile seizures", "E": "History of intussusception"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 50-year-old woman comes to the physician because of blisters on her forearm that appeared 3 days ago. She also reports pain in her left cheek when eating and pain during sexual intercourse for the past week. She has not been sick for the past 6 months. She has started hiking in the woods on the weekends with her son a couple months ago but has been careful to avoid poison ivy. She has a history of hypertension and osteoarthritis. She recently started taking captopril and stopped taking meloxicam 2 weeks ago. She has a family history of pernicious anemia and Graves' disease. The patient's vital signs are within normal limits. Examination reveals multiple, flaccid blisters on the volar surface of the forearm and ulcers on the buccal, gingival, and vulvar mucosa. The epidermis on the forearm separates when the skin is lightly stroked. The total body surface area involvement of the blisters is estimated to be 10%. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Pemphigus vulgaris", "options": {"A": "Lichen planus", "B": "Toxic epidermal necrolysis", "C": "Dermatitis herpetiformis", "D": "Bullous pemphigoid", "E": "Pemphigus vulgaris"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old man presents to his primary care physician for pain in his left ankle. The patient states that he was at karate practice when he suddenly felt severe pain in his ankle forcing him to stop. The patient has a past medical history notable for type I diabetes and is currently being treated for an episode of acute bacterial sinusitis with moxifloxacin. The patient recently had to have his insulin dose increased secondary to poorly controlled blood glucose levels. Otherwise, the patient takes ibuprofen for headaches and loratadine for seasonal allergies. Physical exam reveals a young healthy man in no acute distress. Pain is elicited over the Achilles tendon with dorsiflexion of the left foot. Pain is also elicited with plantar flexion of the left foot against resistance. Which of the following is the best next step in management?", "answer": "Change antibiotics and refrain from athletic activities", "options": {"A": "Change antibiotics and refrain from athletic activities", "B": "Ibuprofen and rest", "C": "Orthopedic ankle brace", "D": "Refrain from athletic activities for 1 to 2 weeks", "E": "Rehabilitation exercises and activity as tolerated"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator is studying the replication of a virus in denucleated embryonic fibroblasts. After the fibroblasts are infected with the virus, viral proteins are directly translated from the virion's genetic material using fibroblast ribosomes. The resultant large polypeptides are then cleaved into smaller peptides by viral proteases to generate mature viral proteins. Finally, the virion's genetic material is replicated using a protein translated from the virion's genetic material. Which of the following is the most likely virus being evaluated in this study?", "answer": "Coxsackievirus", "options": {"A": "Human immunodeficiency virus", "B": "Parvovirus", "C": "Molluscum contagiosum virus", "D": "Measles virus", "E": "Coxsackievirus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old man with a past medical history of HIV is hospitalized with a disseminated zoster infection and treated with IV acyclovir. His course of illness worsens on the 4th day after admission and his creatinine level increases to 4.2 mg/dL. Urinalysis shows birefringent needle-shaped crystals. What could have prevented this deterioration in the patient's renal function?", "answer": "Adequate initial hydration", "options": {"A": "Initial administration of glucocorticoids", "B": "Monitoring of drug levels", "C": "Obtaining a thorough history of patient allergies", "D": "Adequate initial hydration", "E": "Initial administration of allopurinol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 81-year-old man presents to his primary care physician with a 4-month history of shortness of breath. He says that he has slowly lost the ability to do things due to fatigue and now gets winded after walking around the house. He also says that his cough has been getting worse and seems to be producing more sputum. He has gained about 5 pounds over the last 6 months. His past medical history is significant for hypertension and diabetes. He has a 40 pack-year smoking history and drinks about 3 drinks per week. Physical exam reveals a cyanotic appearing man with 1+ edema in his legs bilaterally. He also has wheezing on lung auscultation with a prolonged expiratory phase. Which of the following would most likely be seen on a chest radiograph in this patient?", "answer": "Cardiomegaly and increased bronchial markings", "options": {"A": "Calcified pleural plaques surrounding the diaphragm", "B": "Cardiomegaly and increased bronchial markings", "C": "Hyperinflated lungs and loss of lung markings", "D": "Perihilar mass with unilateral hilar enlargement", "E": "Subpleural cystic enlargement"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old man presents to his primary care physician because he feels like his vision has been changing over the last 6 months. In particular, he feels that he cannot see as well out of his right eye as previously. His past medical history is significant for myocardial infarction as well as Lyme disease. On presentation, he is found to have a droopy right eyelid as well as persistent constriction of his right pupil. Additionally, the skin on his right half of his face is found to be cracked and dry. Which of the following is most likely associated with this patient's symptoms?", "answer": "Pancoast tumor", "options": {"A": "Drug use", "B": "Facial nerve damage", "C": "Oculomotor nerve damage", "D": "Pancoast tumor", "E": "Syphilis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought to the emergency department after he fell on the playground in kindergarten and was unable to get up. His right leg was found to be bent abnormally at the femur, and he was splinted on site by first responders. His past medical history is significant for multiple prior fractures in his left humerus and femur. Otherwise, he has been hitting normal developmental milestones and appears to be excelling in kindergarten. Physical exam also reveals the finding shown in figure A. Which of the following is the most likely cause of this patient's multiple fractures?", "answer": "Increased adenylyl cyclase activity", "options": {"A": "Abnormal collagen production", "B": "Decreased collagen hydroxylation", "C": "Increased adenylyl cyclase activity", "D": "Mutation in neurofibromin", "E": "Non-accidental trauma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old woman is brought to the emergency department after she started convulsing in the office. She has no previous history of seizures and recovers by the time she arrives at the emergency department. She says that over the last 2 days she has also experienced insomnia, abdominal pain, and dark urine. Her past medical history is significant for asthma; however, she says that she has not experienced any of these symptoms previously. She smokes 1 pack of cigarettes per day, drinks a glass of wine with dinner every night, and is currently taking oral contraceptive pills (OCPs). On presentation, her temperature is 99°F (37.2°C), blood pressure is 140/98 mmHg, pulse is 112/min, and respirations are 11/min. Which of the following enzymes is most likely to be defective in this patient?", "answer": "Porphobilinogen deaminase", "options": {"A": "Aminolevulinate dehydratase", "B": "Aminolevulinate synthase", "C": "Ferrochelatase", "D": "Porphobilinogen deaminase", "E": "Uroporphyrinogen decarboxylase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old is brought to the pediatrician by his mother because she is concerned about recent changes to his behavior. She states that he has seemed to regress in his motor development and has been having occasional brief episodes of uncontrollable shaking. During the subsequent work up, a muscle biopsy is obtained which demonstrates red ragged fibers and a presumptive diagnosis of a genetic disease made. The mother asks if her other son will be affected. What should be the physician's response?", "answer": "There is a 100% he will be affected, but the severity may be different", "options": {"A": "There is a 100% he will be affected, but the severity may be different", "B": "There is a 25% chance he will be affected", "C": "He will be unaffected", "D": "There is a 100% he will be affected, and the severity will be the same", "E": "There is a 50% chance he will be affected"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A group of researchers studying the relationship between major depressive disorder and unprovoked seizures identified 36 patients via chart review who had been rehospitalized for unprovoked seizures following discharge from an inpatient psychiatric unit and 105 patients recently discharged from the same unit who did not experience unprovoked seizures. The results of the study show:\nUnprovoked seizure No seizure\nMajor depressive disorder 20 35\nNo major depressive disorder 16 70\nBased on this information, which of the following is the most appropriate measure of association between history of major depressive disorder (MDD) and unprovoked seizures?\"", "answer": "2.5", "options": {"A": "0.36", "B": "1.95", "C": "0.19", "D": "2.5", "E": "0.17"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 56-year-old man of Nepalese origin presents to a clinic complaining of skin rashes that have been troubling him for years. On examination, there are numerous poorly demarcated skin lesions present on all parts of the body. There is also evidence of significant facial thickening, eyebrow loss, and symmetrical sensory neuropathy in a ‘glove and stocking’ distribution. An examination of the hands reveals bilateral weakness. A skin biopsy is taken from one of the lesions, and the culture is positive for acid-fast bacilli. Which of the following pharmacological therapies is involved in the treatment of this condition?", "answer": "Dapsone", "options": {"A": "Dapsone", "B": "Flucloxacillin", "C": "Isoniazid", "D": "Ketoconazole", "E": "Prednisone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 16-year-old girl comes to the physician because of episodic lower abdominal pain for 5 months. The pain starts to occur a few hours before her menses and lasts for 2–3 days. Ibuprofen helped reduce the pain in the first months but has no effect now. She has missed a couple of days at school because of severe pain. Menarche was at the age of 14 years, and menses occur at regular 29-day intervals. She is sexually active with one male partner and uses condoms inconsistently. Her temperature is 37.1°C (98.8°F), pulse is 88/min, and blood pressure is 110/70 mm Hg. Physical and pelvic examination show no abnormalities. A urine pregnancy test is negative. Which of the following is the most appropriate next step in management?", "answer": "Oral contraceptive pill", "options": {"A": "Diagnostic laparoscopy", "B": "Ceftriaxone and doxycycline therapy", "C": "Pelvic ultrasonography", "D": "Oral contraceptive pill", "E": "Urinalysis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A medical examiner was called to investigate the death of a 75-year-old type 1 diabetic Caucasian male who was a retired physician. His caretaker discovered his body in the bedroom with an empty syringe and a small bottle of lispro lying on the nightstand. She explains that his wife of 50 years passed away six months ago and that he had no children or family. He had become extremely depressed and did not want to live anymore. Which of the following would be most consistent with his blood chemistry if a blood sample were taken?", "answer": "Glucose: 25 mg/dL, high insulin and absent C-peptide levels", "options": {"A": "Glucose: 25 mg/dL, high insulin and high C-peptide levels", "B": "Glucose: 25 mg/dL, high insulin and normal C-peptide levels", "C": "Glucose: 25 mg/dL, high insulin and absent C-peptide levels", "D": "Glucose: 95 mg/dL, low insulin and low C-peptide levels", "E": "Glucose: 95 mg/dL, high insulin and C-peptide levels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old woman makes a follow-up appointment with her primary care physician for evaluation of her diabetes medications. Specifically, she complains that she has been experiencing flushing, nausea, and palpitations after drinking a glass of wine with dinner after she started the latest regimen for her diabetes. She was warned that this was a side-effect of one of her medications but she did not understand the severity of the reaction. Given this experience, she asks to be placed on an alternative regimen that does not involve the medication that caused this reaction. Her physician therefore replaces the medication with another one that interacts with the same target though at a different binding site. Which of the following is a side-effect of the new medication?", "answer": "Weight gain", "options": {"A": "Hepatotoxicity", "B": "Lactic acidosis", "C": "Pancreatitis", "D": "Urinary tract infection", "E": "Weight gain"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old girl is brought to the physician by her mother two days after the sudden onset of a rash. The mother says that the rash developed an hour after she bathed the child in lukewarm water. Two weeks ago, the patient was diagnosed with a skin infection and was treated with penicillin V. She has been otherwise healthy but has missed several well-child examinations. She lives with her single mother, who recently lost her job and is now dependent on social assistance. The patient's mother has major depressive disorder and her maternal aunt has systemic lupus erythematosus. The girl's temperature is 36.8°C (98.2°F), pulse is 112/min, and blood pressure is 108/62 mm Hg. She has poor eye contact. Physical examination shows sharply delineated erythema on the lower extremities up to the umbilicus with sparing of the knees and flexor surfaces. Further evaluation is most likely to reveal which of the following?", "answer": "Multiple injuries in different stages of healing", "options": {"A": "Multiple injuries in different stages of healing", "B": "Dermatographism", "C": "Positive Nikolsky's sign", "D": "Malar rash with sparing of the nasolabial folds", "E": "Ulcers of the oral mucosa\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 2-year-old girl with a history of SS-hemoglobin is brought to her pediatrician by her mother, who noted an abdominal mass. On exam, the girl's spleen is palpably enlarged, and her palms and conjunctiva are noted to be extremely pale. Serum haptoglobin levels are normal. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Extravascular hemolysis", "options": {"A": "Decreased red blood cell production", "B": "Extravascular hemolysis", "C": "Intravascular hemolysis", "D": "Complement-mediated hemolysis", "E": "Hemolytic uremic syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 19-year-old woman comes to the physician because of a delayed menstrual period. She has had regular menses since menarche at age 11. Her last menstrual period was 7 weeks ago. She is sexually active with two male partners. A urine pregnancy test is positive. An ultrasound of the pelvis shows a viable intrauterine pregnancy with an estimated gestational age of 6 weeks and 5 days. She does not wish to continue with the pregnancy. After carefully weighing the options with her physician, she is prescribed two medications, one of which is mifepristone. Which of the following is this drug's primary mechanism of action?", "answer": "Blockage of progesterone receptor", "options": {"A": "Inhibition of dihydrofolate reductase", "B": "Blockage of progesterone receptor", "C": "Activation of prostaglandin E1 receptors", "D": "Antagonist at gonadotropin-releasing hormone receptors", "E": "Agonist at oxytocin receptors"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 97-year-old man visits the urology clinic 5 days after experiencing urinary retention at an emergency department visit. The patient has a history of hypertension, type II diabetes mellitus, stroke, dyslipidemia, a past myocardial infarction, and severe osteoarthritis in his right hip. He is not compliant with his medications and his multiple comorbidities are poorly managed. In the hospital, the patient’s urinary retention was treated with Foley catheterization. At clinic, the patient’s serum-specific prostate-specific antigen (PSA) is 6.0 ng/mL (normal is < 4 ng/mL). Digital rectal examination (DRE) demonstrates a nontender prostate with several rock hard nodules. The patient's Foley is removed and he is able to urinate on his own. Which is the most appropriate next step in management?", "answer": "Reassurance", "options": {"A": "CT abdomen and pelvis", "B": "Cystourethroscopy", "C": "Transrectal prostate biopsy", "D": "Reassurance", "E": "Repeat PSA test"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 66-year-old woman presents to the emergency department with lower extremity pain. She reports that she has had worsening pain in her left calf over the past year while walking. The pain improves with rest, but the patient notes that she now has to stop walking more frequently than in the past to relieve the pain. The patient’s past medical history is otherwise notable for hypertension and coronary artery disease. Her home medications include hydrochlorothiazide and lisinopril. Her family history is significant for diabetes mellitus in her father. On physical exam, her left lower extremity is slightly cool to the touch with palpable distal pulses. The skin of the left lower extremity appears smooth and shiny below the mid-calf. Laboratory testing is performed and reveals the following:\n\n\n\nSerum:\n\nHigh-density lipoprotein (HDL): 60 mg/dL\n\nLow-density lipoprotein (LDL): 96 mg/dL\n\nTriglycerides: 140 mg/dL\n\n\n\nThis patient should be started on which of the following medication regimens?", "answer": "Aspirin and atorvastatin", "options": {"A": "Aspirin only", "B": "Aspirin and atorvastatin", "C": "Aspirin and cilostazol", "D": "Atorvastatin only", "E": "Atorvastatin and cilostazol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 50-year-old man comes to the emergency department for evaluation of right-sided facial weakness that he noticed after waking up. One month ago, he also experienced right-sided neck pain and headache that began after returning from a hunting trip to New Hampshire the week before. He took ibuprofen to relieve symptoms, which subsided a week later. He has a 5-year history of hypertension controlled with drug therapy. He has smoked one pack of cigarettes daily for 35 years and he drinks two beers daily. His vital signs are within the normal range. Physical examination shows right-sided drooping of the upper and lower half of the face. The patient has difficulties smiling and he is unable to close his right eye. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in diagnosis?", "answer": "Enzyme‑linked immunosorbent assay", "options": {"A": "Western blot", "B": "Polymerase chain reaction of the facial skin", "C": "Cerebrospinal fluid analysis", "D": "Enzyme‑linked immunosorbent assay", "E": "Noncontrast CT"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought to the physician because of a 10-day history of intermittent fevers and painful swelling of the right ankle. He has not had trauma to the ankle. He has a history of sickle cell disease and had an episode of dactylitis of his left index finger 3 years ago. Current medications include hydroxyurea and acetaminophen as needed for the ankle pain. His temperature is 38°C (100.4°F), blood pressure is 125/68 mm Hg, pulse is 105/min, and respirations are 14/min. Examination shows a tender, swollen, and erythematous right ankle with point tenderness over the medial malleolus. X-ray of the right ankle demonstrates marked periosteal thickening and elevation, as well as a central sclerotic lesion with a lucent rim over the right lateral malleolus. A bone biopsy culture confirms the diagnosis. Which of the following is the most likely causal organism?", "answer": "Salmonella enterica", "options": {"A": "Streptococcus pneumoniae", "B": "Escherichia coli", "C": "Streptococcus pyogenes", "D": "Salmonella enterica", "E": "Pseudomonas aeruginosa"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old woman presents to the emergency department with moderate right wrist pain after falling on her outstretched hand. She has numbness in the 3 medial digits. The patient has no known previous medical conditions. Her family history is not pertinent, and she currently takes no medications. Physical examination shows her blood pressure is 134/82 mm Hg, the respirations are 14/min, the pulse is 87/min, and the temperature is 36.7°C (98.0°F). When asked to make a fist, the patient is able to flex only the lateral 2 digits. Tapping the anterior portion of her wrist elicits tingling in the medial 3 digits. The patient is taken to get an X-ray. Which of the following is the most likely diagnosis for this patient’s injury?", "answer": "Lunate dislocation", "options": {"A": "Scaphoid fracture", "B": "Lunate dislocation", "C": "Fracture of distal radius", "D": "Palmar aponeurosis tear", "E": "Interosseous ligament rupture"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old woman visits the clinic expressing a desire to become pregnant. She was seen for depressed mood and disinterest in her usual leisure activities a few months ago. She also had decreased sleep and appetite and was not able to concentrate at work. She was started on fluoxetine and has been compliant for the last 6 months despite experiencing some of the side effects. She now feels significantly better and would like to stop the medication because she plans to become pregnant and thinks it is unnecessary now. Which of the following statements is correct regarding this patient’s current antidepressant therapy?", "answer": "It can cause anorgasmia.", "options": {"A": "It can cause anorgasmia.", "B": "It has the shortest half-life of any drugs in the same class.", "C": "It is unsafe to take during pregnancy.", "D": "It decreases levels of concurrent neuroleptics.", "E": "Most side effects persist throughout therapy."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old man presents to his primary care provider because of fatigue and loss of appetite. He is also concerned that his legs are swollen below the knee. He has had type 2 diabetes for 35 years, for which he takes metformin and glyburide. Today his temperature is 36.5°C (97.7°F), the blood pressure is 165/82 mm Hg, and the pulse is 88/min. Presence of which of the following would make diabetic kidney disease less likely in this patient?", "answer": "Cellular casts in urinalysis", "options": {"A": "Nephrotic range proteinuria", "B": "Diabetic retinopathy", "C": "Cellular casts in urinalysis", "D": "Gradual reduction of glomerular filtration rate (GFR)", "E": "Normal-to-large kidneys on ultrasound"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 33-year-old woman presents to the clinic complaining of yellowish discoloration of her skin and eyes, mild fever, and body aches. She has had this problem for 6 months, but it has become worse over the past few weeks. She also complains of repeated bouts of bloody diarrhea and abdominal pain. The past medical history is noncontributory. She takes no medication. Both of her parents are alive with no significant disease. She works as a dental hygienist and drinks wine occasionally on weekends. Today, the vital signs include blood pressure 110/60 mm Hg, pulse rate 90/min, respiratory rate 19/min, and temperature 36.6°C (97.8°F). On physical examination, she appears uncomfortable. The skin and sclera are jaundiced. The heart has a regular rate and rhythm, and the lungs are clear to auscultation bilaterally. The abdomen is soft with mild hepatosplenomegaly. There is no tenderness or rebound tenderness. The digital rectal examination reveals blood and mucus in the rectal vault. Laboratory studies show:\nSerum sodium 140 mEq/L\nSerum potassium 3.8 mEq/L\n  Alanine aminotransferase (ALT) 250 U/L\nAspartate aminotransferase (AST) 170 U/L\nAlkaline phosphatase (ALP) 120 U/L\nWhich of the following antibodies would you expect to find in this patient?", "answer": "Perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA)", "options": {"A": "Anti-mitochondrial antibody", "B": "Anti-endomysial IgA", "C": "Perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA)", "D": "Anti-cyclic citrullinated peptide (anti-CCP)", "E": "Anti-double stranded DNA (anti-dsDNA)"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 11-year-old male presents to the pediatrician with his mother for evaluation of difficulty walking. His mother reports that the patient was walking normally until about a year ago, when he started to complain of weakness in his legs. He seems to be less steady on his feet than before, and he has fallen twice at home. Prior to a year ago, the patient had no difficulty walking and was active on his school’s soccer team. He has no other past medical history. The patient is an only child, and his mother denies any family history of neurological disease. On physical examination, the patient has mildly slurred speech. He has a wide-based gait with symmetric weakness and decreased sensation in his lower extremities. The patient also has the physical exam findings seen in Figures A and B. Which of the following is the most likely etiology of this patient’s presentation?", "answer": "Trinucleotide (GAA) repeat expansion on chromosome 9", "options": {"A": "Genetic mutation on chromosome 11q22", "B": "Infection with gram-negative rods", "C": "Trinucleotide (CGG) repeat expansion on chromosome X", "D": "Trinucleotide (CTG) repeat expansion on chromosome 19", "E": "Trinucleotide (GAA) repeat expansion on chromosome 9"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-month-old girl is brought to the physician by her mother because of a 4-day history of vomiting, poor feeding, and more frequent napping. She appears lethargic. Her vital signs are within normal limits. Physical examination shows a bulging, tense anterior fontanelle. Fundoscopic exam shows bilateral retinal hemorrhage. A complete blood count shows a leukocyte count of 8,000/mm3. An x-ray of the chest shows healing fractures of the 4th and 5th left ribs. Which of the following is the most likely cause of the patient's condition?", "answer": "Shearing head injury", "options": {"A": "Malnutrition", "B": "Shearing head injury", "C": "Inherited connective tissue disorder", "D": "Bleeding from the germinal matrix", "E": "Epidural hematoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old G1P0 at 12 weeks estimated gestational age presents for prenatal care. The patient says she has occasional nausea and vomiting and a few episodes of palpitations and diarrhea this last week. Physical examination is unremarkable, except for a heart rate of 145/min. Basic thyroid function tests are shown in the table below. Which of the following additional laboratory tests would be most useful is assessing this patient’s condition?\nThyroid-stimulating hormone (TSH) \n0.28 mIU/L (0.3–4.5 mIU/L)\nTotal T4\n12 µg/dL (5.4–11.5 µg/dL)", "answer": "Free thyroxine (T4) levels", "options": {"A": "Total triiodothyronine (T3) levels", "B": "Free thyroxine (T4) levels", "C": "Thyroxine-binding globulin (TBG) levels", "D": "Thyroid peroxidase (TPO) antibodies", "E": "Thyrotropin receptor antibodies (TRAb)"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 1-year-old girl is brought to the physician for follow-up examination 1 week after admission to the hospital for bacterial pneumonia. She has had multiple episodes of purulent otitis media and infectious diarrhea since the age of 6 months. She underwent treatment for oral thrush 1 month ago. There is no family history of serious illness. Her height and weight are both below the 10th percentile. Physical examination shows no visible tonsils and slightly decreased breath sounds in the left lower lobe. Laboratory studies show increased deoxyadenosine concentration in both the serum and urine. An x-ray of the chest shows an absent thymic shadow. Which of the following additional findings is most likely in this patient?", "answer": "Decreased circulating T cells", "options": {"A": "Decreased circulating parathyroid hormone", "B": "Increased circulating IgE", "C": "Decreased circulating T cells", "D": "Decreased circulating platelets", "E": "Increased circulating neutrophils"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old man presents to his primary care doctor for a 2 month follow-up appointment. He had recently separated from his male partner of 10 years and has been struggling to maintain his weight and the rigors of work in a new start-up company. At his initial visit, he was prescribed escitalopram. 2 weeks later, the patient was instructed to continue taking the medication despite feeling more depressed. After expressing increased desire to carry out suicidal thoughts, he was hospitalized for a brief course. During this visit, he reports that he is feeling much better, but he has an elective inguinal hernia repair scheduled for the end of the week. \"The surgeon said to not take anything before the surgery. Besides, I'm feeling better and don't feel like taking escitalopram everyday.\" What is the most appropriate response?", "answer": "Continue escitalopram on day of surgery and continue afterwards for 4 more months", "options": {"A": "Continue escitalopram on day of surgery and continue afterwards for 4 more months", "B": "Continue escitalopram until surgery and discontinue afterwards", "C": "Discontinue escitalopram", "D": "Hold escitalopram the day before surgery and continue afterwards for 4 more months", "E": "Hold escitalopram the day of surgery and continue afterwards for 4 more months"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 66-year-old man comes to the physician because of difficulty walking for the past year. He reports that his gait has become slower and that initiating steps has become more challenging. During the past 6 months, his family has noticed that he is starting to forget important family meetings and holidays. On a number of occasions, he has not been able to get to the bathroom in time in order to urinate. He has hypertension treated with hydrochlorothiazide. His father died of Parkinson's disease at the age of 63 years. The patient had smoked one pack of cigarettes daily for 40 years, but quit 10 years ago. His vital signs are within normal limits. On mental status examination, he is confused and has short-term memory deficits. He has a wide-based, shuffling gait. Muscle strength is normal. Deep tendon reflexes are 2+ bilaterally. An MRI of the head is shown. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Decreased cerebrospinal fluid absorption", "options": {"A": "Normal changes associated with aging", "B": "Increased cerebrospinal fluid production", "C": "Decreased cerebrospinal fluid absorption", "D": "Obstructed passage of cerebrospinal fluid", "E": "Degeneration of cholinergic neurons in the temporal lobe"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old woman presents with right leg pain and swelling of 5 days’ duration. She has a history of hypertension for 15 years and had a recent hospitalization for pneumonia. She had been recuperating at home but on beginning to mobilize and walk, the right leg became painful and swollen. Her temperature is 37.1°C (98.7°F), the blood pressure is 130/80 mm Hg, and the pulse is 75/min. On physical examination, the right calf is 4 cm greater in circumference than the left when measured 10 cm below the tibial tuberosity. Dilated superficial veins are present on the right foot and the right leg is slightly redder than the left. There is some tenderness on palpation in the popliteal fossa behind the knee. Which of the following is the best initial step in the management of this patient’s condition?", "answer": "Wells’ clinical probability tool", "options": {"A": "Wells’ clinical probability tool", "B": "Computerized tomography (CT) with contrast", "C": "International randomized ratio (INR)", "D": "Thrombophilia screen", "E": "Activated partial thromboplastin time (aPTT)"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 71-year-old man with Hodgkin lymphoma is admitted to the hospital with lower back pain and no urine output over the last 12 hours. Physical examination shows inguinal lymphadenopathy. There is no suprapubic fullness or tenderness. Serum creatinine is elevated compared to 1 week prior. A contrast-enhanced CT scan of the abdomen shows retroperitoneal fibrosis, bilateral hydronephrosis, and a collapsed bladder. Which of the following is the next appropriate step in management of this patient?", "answer": "Perform ureteral stenting", "options": {"A": "Place a urethral catheter", "B": "Perform ureteral stenting", "C": "Initiate oxybutynin therapy", "D": "Place a suprapubic catheter", "E": "Initiate tamsulosin therapy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old African-American woman comes to the physician for a routine checkup. She feels well. She has a history of type 2 diabetes mellitus that is well-controlled with metformin. Her mother died of a progressive lung disease at the age of 50 years. The patient is sexually active with her husband, and they use condoms consistently. She has smoked one pack of cigarettes daily for the past 10 years. She drinks one to two glasses of wine per day. She does not use illicit drugs. Vital signs are within normal limits. Examination, including ophthalmologic evaluation, shows no abnormalities. Laboratory studies, including serum creatinine and calcium concentrations, are within normal limits. An ECG shows no abnormalities. A tuberculin skin test is negative. A chest x-ray is shown. Which of the following is the most appropriate next step in management?", "answer": "Monitoring", "options": {"A": "ANCA testing", "B": "Lung biopsy", "C": "Oral methotrexate therapy", "D": "Monitoring", "E": "Oral isoniazid monotherapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A research scientist attempts to understand the influence of carbon dioxide content in blood on its oxygen binding. The scientist adds carbon dioxide to dog blood and measures the uptake of oxygen in the blood versus oxygen pressure in the peripheral tissue. He notes in one dog that with the addition of carbon dioxide with a pressure of 90 mmHg, the oxygen pressure in the peripheral tissue rose from 26 to 33 mmHg. How can this phenomenon be explained?", "answer": "High partial pressure of CO2 in tissues facilitates O2 unloading in peripheral tissues", "options": {"A": "Binding of O2 to hemoglobin in lungs drives release of CO2 from hemoglobin", "B": "The sum of the partial pressures of CO2 and O2 cannot exceed a known threshold in blood", "C": "High partial pressure of CO2 in tissues facilitates O2 unloading in peripheral tissues", "D": "High partial pressure of CO2 in tissues decreases peripheral blood volume", "E": "High partial pressure of CO2 in tissues causes alkalemia, which is necessary for O2 unloading"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A young man about to leave for his freshman year of college visits his physician in order to ensure that his immunizations are up-to-date. Because he is living in a college dormitory, his physician gives him a vaccine that prevents meningococcal disease. What type of vaccine did this patient likely receive?", "answer": "Conjugated polysaccharide", "options": {"A": "Live, attenuated", "B": "Killed, inactivated", "C": "Toxoid", "D": "Conjugated polysaccharide", "E": "Killed, attenuated"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old woman comes to the military physician because of a 2-day history of fever, joint pain, dry cough, chest pain, and a painful red rash on her lower legs. Two weeks ago, she returned from military training in Southern California. She appears ill. Her temperature is 39°C (102.1°F). Physical examination shows diffuse inspiratory crackles over all lung fields and multiple tender erythematous nodules over the anterior aspect of both legs. A biopsy specimen of this patient's lungs is most likely to show which of the following?", "answer": "Spherules filled with endospores", "options": {"A": "Spherules filled with endospores", "B": "Broad-based budding yeast", "C": "Oval, budding yeast with pseudohyphae", "D": "Septate hyphae with acute-angle branching", "E": "Round yeast surrounded by budding yeast cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "a 34-year-old G2P2 woman presents to her obstetrician because of new onset discharge from her breast. She first noticed it in her bra a few days ago, but now she notes that at times she's soaking through to her blouse, which is mortifying. She was also concerned about being pregnant because she has not gotten her period in 3 months. In the office ß-HCG is negative. The patient's nipple discharge is guaiac negative. Which of the following therapies is most appropriate?", "answer": "Cabergoline", "options": {"A": "Tamoxifine", "B": "Leuprolide", "C": "Haloperidol", "D": "Cabergoline", "E": "Carbidopa-levodopa"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old woman returns to the outpatient oncology clinic to follow up on her recently diagnosed breast cancer. A few months ago, she noticed a lump during a breast self-exam that was shown to be breast cancer. A lumpectomy revealed invasive ductal carcinoma that was estrogen- and progesterone receptor-positive with nodal metastases. She is following up to discuss treatment options. She had her last menstrual period 10 years ago and has not had any spotting since that time. Her mother had breast cancer and she remembered her taking chemotherapy and had a poor quality of life, thus she asks not to be treated similarly. Which of the following is the mechanism of action of the best treatment option for this patient?", "answer": "Inhibit peripheral conversion of androgens to estrogen", "options": {"A": "Antagonist for estrogen receptors in the breast", "B": "Cell cycle arrest", "C": "Antagonist for estrogen receptors in the hypothalamus", "D": "Inhibit peripheral conversion of androgens to estrogen", "E": "Estrogen receptors downregulation in the breast"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old girl comes to the emergency department because of numbness around her mouth and uncontrolled twitching of the mouth for the past 30 minutes. Her symptoms began while she was at a concert. Her temperature is 37°C (98.6°F), pulse is 69/min, and respirations are 28/min. When the blood pressure cuff is inflated, painful contractions of the hand muscles occur. Arterial blood gas shows a pH of 7.53, pO2 of 100 mm Hg, and a pCO2 of 29 mm Hg. Which of the following additional findings is most likely in this patient?", "answer": "Decreased cerebral blood flow", "options": {"A": "Decreased cerebral blood flow", "B": "Increased peripheral oxygen unloading from hemoglobin", "C": "Decreased total serum calcium concentration", "D": "Increased serum potassium concentration", "E": "Increased serum phosphate concentration"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old woman is brought to the emergency department after being found unresponsive in her bedroom in a nursing home facility. Her past medical history is relevant for hypertension, diagnosed 5 years ago, for which she has been prescribed a calcium channel blocker and a thiazide diuretic. Upon admission, she is found with a blood pressure of 200/116 mm Hg, a heart rate of 70/min, a respiratory rate of 15 /min, and a temperature of 36.5°C (97.7°F). Her cardiopulmonary auscultation is unremarkable, except for the identification of a 4th heart sound. Neurological examination reveals the patient is stuporous, with eye-opening response reacting only to pain, no verbal response, and flexion withdrawal to pain. Both pupils are symmetric, with the sluggish pupillary response to light. A noncontrast CT of the head is performed and is shown in the image. Which of the following is the most likely etiology of this patient’s condition?", "answer": "Charcot-Bouchard aneurysm rupture", "options": {"A": "Charcot-Bouchard aneurysm rupture", "B": "Arteriovenous malformation rupture", "C": "Dural arteriovenous fistula", "D": "Venous sinus thrombosis", "E": "Hemorrhagic transformation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 11-year-old boy presents to his pediatrician with muscle cramps and fatigue that have progressively worsened over the past year. His mom says that he has always had occasional symptoms including abdominal pain, muscle weakness, and mild paresthesias; however, since starting middle school these symptoms have started interfering with his daily activities. In addition, the boy complains that he has been needing to use the restroom a lot, which is annoying since he has to ask for permission to leave class every time. Labs are obtained showing hypokalemia, hypochloremia, metabolic alkalosis, hypomagnesemia, and hypocalciuria. The most likely cause of this patient's symptoms involves a protein that binds which of the following drugs?", "answer": "Hydrochlorothiazide", "options": {"A": "Amiloride", "B": "Furosemide", "C": "Hydrochlorothiazide", "D": "Mannitol", "E": "Spironolactone"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 67-year-old man with a 55-pack-year smoking history, diabetes type II, and hyperlipidemia presents to his primary care clinic for an annual exam. He has no complaints. He reports that his blood glucose has been under tight control and that he has not smoked a cigarette for the past 5 months. His temperature is 97.5°F (36.4°C), blood pressure is 182/112 mmHg, pulse is 85/min, respirations are 15/min, and oxygen saturation is 95% on room air. Physical examination is notable for bruits bilaterally just lateral of midline near his umbilicus. The patient is started on anti-hypertensive medications including a beta-blocker, a thiazide diuretic, and a calcium channel blocker. He returns 1 month later with no change in his blood pressure. Which of the following is the best next step in management?", "answer": "Renal ultrasound with Doppler", "options": {"A": "CT abdomen/pelvis", "B": "Increase dose of current blood pressure medications", "C": "Lisinopril", "D": "Renal ultrasound with Doppler", "E": "Surgical revascularization"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old girl presents to a new pediatrician with fever, shortness of breath, and productive cough. She had similar symptoms a few weeks ago. The girl was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and is meeting all developmental milestones. A further review of her history reveals seizures, upper respiratory infections, and cellulitis. On physical examination, the patient is pale with white-blonde hair and pale blue eyes. Which of the following would you expect to see on a peripheral blood smear for this patient?", "answer": "Polymorphonuclear leukocytes containing giant inclusion bodies", "options": {"A": "Predominance of band leukocytes", "B": "Stippled eosinophils", "C": "Downey cells", "D": "Polymorphonuclear leukocytes containing giant inclusion bodies", "E": "Significant basophil predominance"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old female presents to her pediatrician's office requesting to be started on an oral contraceptive pill. She has no significant past medical history and is not currently taking any medications. The physician is a devout member of the Roman Catholic church and is strongly opposed to the use of any type of artificial contraception. Which of the following is the most appropriate response to this patient's request?", "answer": "Explain that he will refer the patient to one of his partners who can fulfill this request", "options": {"A": "The physician is obligated to prescribe the oral contraceptives regardless of his personal beliefs", "B": "Refuse to prescribe the oral contraceptive", "C": "Suggest that the patient remain abstinent or, if necessary, use an alternative means of birth control", "D": "Explain that he will refer the patient to one of his partners who can fulfill this request", "E": "Tell the patient that he is unable to prescribe this medication without parental consent"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 14-year-old boy presents to the emergency department with an intractable nosebleed. Pinching of the nose has failed to stop the bleed. The patient is otherwise healthy and has no history of trauma or hereditary bleeding disorders. His temperature is 98.9°F (37.2°C), blood pressure is 120/64 mmHg, pulse is 85/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam is notable for multiple clots in the nares which, when dislodged, are followed by bleeding. Which of the following location is the most likely etiology of this patient's symptoms?", "answer": "Kiesselbach plexus", "options": {"A": "Carotid artery", "B": "Ethmoidal artery", "C": "Kiesselbach plexus", "D": "Septal hematoma", "E": "Sphenopalatine artery"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old male arrives in the emergency department with a stab wound over the precordial chest wall. The patient is in distress and is cold, sweaty, and pale. Initial physical examination is significant for muffled heart sounds, distended neck veins, and a 3 cm stab wound near the left sternal border. Breath sounds are present bilaterally without evidence of tracheal deviation. Which of the following additional findings would be expected on further evaluation?", "answer": "15 mmHg decrease in systolic blood pressure with inspiration", "options": {"A": "Decrease in the patient's heart rate by 15 beats per minute with inspiration", "B": "Elevated blood pressure to 170/110", "C": "Steadily decreasing heart rate to 60 beats per minute", "D": "15 mmHg decrease in systolic blood pressure with inspiration", "E": "Decrease in central venous pressure by 5 mmHg with inspiration"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old woman comes to the physician because of a 3-day history of worsening shortness of breath, nonproductive cough, and sharp substernal chest pain. The chest pain worsens on inspiration and on lying down. The patient was diagnosed with breast cancer 2 months ago and was treated with mastectomy followed by adjuvant radiation therapy. She has hypertension and hyperlipidemia. Current medications include tamoxifen, valsartan, and pitavastatin. She has smoked a pack of cigarettes daily for 15 years but quit after being diagnosed with breast cancer. Her pulse is 95/min, respirations are 20/min, and blood pressure is 110/60 mm Hg. Cardiac examination shows a scratching sound best heard at the left lower sternal border. An ECG shows sinus tachycardia and ST segment elevations in leads I, II, avF, and V1–6. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Neutrophilic infiltration of the pericardium", "options": {"A": "Dystrophic calcification of the mitral valve", "B": "Embolic occlusion of a pulmonary artery", "C": "Neutrophilic infiltration of the pericardium", "D": "Subendothelial fibrosis of coronary arteries", "E": "Fibrotic thickening of the pericardium"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old man is brought into the clinic by his wife. She reports that her husband has been feeling down since he lost a big project at work 2 months ago. The patient says he feels unmotivated to work or do things around the house. He also says he is not eating or sleeping as usual and spends most of his day pacing about his room. He feels guilty for losing such a project this late in his career and feels overwhelming fear about the future of his company and his family’s well-being. During the interview, he appears to be in mild distress and is wringing his hands. The patient is prescribed citalopram and buspirone. Which of the following side effects is most commonly seen with buspirone?", "answer": "Lightheadedness", "options": {"A": "Lightheadedness", "B": "Dry mouth", "C": "Respiratory depression", "D": "Anterograde amnesia", "E": "Sleepwalking"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old African-American female presents to the emergency room complaining of chest pain. She also complains of recent onset arthritis and increased photosensitivity. Physical examination reveals bilateral facial rash. Which of the following is most likely to be observed in this patient?", "answer": "Pain relieved by sitting up and leaning forward", "options": {"A": "Pain improves with inspiration", "B": "Pain relieved by sitting up and leaning forward", "C": "High-pitched diastolic murmur", "D": "Fixed and split S2", "E": "Mid-systolic click"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old woman presents to her primary care doctor with her son who reports that his mother is not acting like herself. She has gotten lost while driving several times in the past 2 months and appears to be talking to herself frequently. Of note, the patient’s husband died from a stroke 4 months ago. The patient reports feeling sad and guilty for causing so much trouble for her son. Her appetite has decreased since her husband died. On examination, she is oriented to person, place, and time. She is inattentive, and her speech is disorganized. She shakes her hand throughout the exam without realizing it. Her gait is slow and appears unstable. This patient’s condition would most likely benefit from which of the following medications?", "answer": "Rivastigmine", "options": {"A": "Bromocriptine", "B": "Levodopa", "C": "Reserpine", "D": "Rivastigmine", "E": "Selegiline"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old female with Crohn's disease diagnosed in her early 20s comes to your office for a follow-up appointment. She is complaining of headaches and fatigue. Which of the following arterial blood findings might you expect?", "answer": "Normal Pa02, normal 02 saturation (Sa02), low 02 content (Ca02)", "options": {"A": "Normal Pa02, normal 02 saturation (Sa02), normal 02 content (Ca02)", "B": "Low Pa02, low 02 saturation (Sa02), low 02 content (Ca02)", "C": "Low Pa02, normal 02 saturation (Sa02), normal 02 content (Ca02)", "D": "Normal Pa02, normal 02 saturation (Sa02), low 02 content (Ca02)", "E": "High Pa02, normal 02 saturation (Sa02), normal 02 content (Ca02)"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Four days into hospitalization for severe pneumonia, a 76-year-old woman suddenly becomes unresponsive. She has no history of heart disease. She is on clarithromycin and ceftriaxone. Her carotid pulse is not detected. A single-lead ECG strip is shown. Previous ECG shows QT prolongation. Laboratory studies show:\nSerum\nNa+ 145 mEq/L\nK+ 6.1 mEq/L\nCa2+ 10.5 mEq/L\nMg2+ 1.8 mEq/L\nThyroid-stimulating hormone 0.1 μU/mL\nCardiopulmonary resuscitation has been initiated. Which of the following is the most likely underlying cause of this patient’s recent condition?", "answer": "Clarithromycin", "options": {"A": "Hypercalcemia", "B": "Thyrotoxicosis", "C": "Hyperkalemia", "D": "Clarithromycin", "E": "Septic shock"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old woman comes to the physician for a routine health maintenance examination. She is doing well. She is 168 cm (5 ft 6 in) tall and weighs 75 kg (165 lb); BMI is 27 kg/m2. Her BMI had previously been stable at 24 kg/m2. The patient states that she has had decreased appetite over the past month. The patient's change in appetite is most likely mediated by which of the following?", "answer": "Decreased hypothalamic neuropeptide Y", "options": {"A": "Increased hepatic somatomedin C secretion", "B": "Decreased hypothalamic neuropeptide Y", "C": "Potentiation of cholecystokinin", "D": "Increased fatty acid oxidation", "E": "Inhibition of proopiomelanocortin neurons"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old man is brought to the emergency department after experiencing a seizure. According to his girlfriend, he has had fatigue for the last 3 days and became confused this morning, after which he started having uncontrollable convulsions throughout his entire body. He was unconscious throughout the episode, which lasted about 4 minutes. He has not visited a physician for over 10 years. He has smoked one pack of cigarettes daily for 12 years. His girlfriend admits they occasionally use heroin together with their friends. His temperature is 38.8°C (101.8°F), pulse is 93/min, respirations are 20/min, and blood pressure is 110/70 mm Hg. The lungs are clear to auscultation and examination shows normal heart sounds and no carotid or femoral bruits. He appears emaciated and somnolent. There are multiple track marks on both his arms. He is unable to cooperate for a neurological exam. Laboratory studies show a leukocyte count of 3,000/mm3, a hematocrit of 34%, a platelet count of 354,000/mm3, and an erythrocyte sedimentation rate of 27 mm/h. His CD4+ T-lymphocyte count is 84/mm3 (normal ≥ 500). A CT scan of the head is shown. Which of the following is the most appropriate next step considering this patient's CT scan findings?", "answer": "Pyrimethamine, sulfadiazine, and leucovorin", "options": {"A": "Pyrimethamine, sulfadiazine, and leucovorin", "B": "Trimethoprim-sulfamethoxazole", "C": "CT-guided stereotactic aspiration", "D": "Albendazole", "E": "Glucocorticoids"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old woman presents with fatigue and flu-like symptoms. She says her symptoms started 5 days ago with a low-grade fever and myalgia, which have not improved. For the past 4 days, she has also had chills, sore throat, and rhinorrhea. She works as a kindergarten teacher and says several children in her class have had similar symptoms. Her past medical history is significant for depression managed with escitalopram, and dysmenorrhea. A review of systems is significant for general fatigue for the past 5 months. Her vital signs include: temperature 38.5°C (101.3°F), pulse 99/min, blood pressure 115/75 mm Hg, and respiratory rate 22/min. Physical examination reveals pallor of the mucous membranes. Initial laboratory findings are significant for the following:\nHematocrit 24.5%\nHemoglobin 11.0 g/dL\nPlatelet Count 215,000/mm3\nMean corpuscular volume (MCV) 82 fL\nRed cell distribution width (RDW) 10.5%\nWhich of the following is the best next diagnostic test in this patient?", "answer": "Reticulocyte count", "options": {"A": "Reticulocyte count", "B": "Serum folate level", "C": "Serum ferritin level", "D": "Serum iron level", "E": "Hemoglobin electrophoresis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator is studying collagen synthesis in human fibroblast cells. Using a fluorescent tag, α-collagen chains are identified and then monitored as they travel through the rough endoplasmic reticulum, the Golgi apparatus, and eventually into the extracellular space. Which of the following steps in collagen synthesis occurs extracellularly?", "answer": "Cleavage of procollagen C- and N-terminals", "options": {"A": "Glycosylation of pro-α chains", "B": "Hydroxylation of proline and lysine", "C": "Cleavage of procollagen C- and N-terminals", "D": "Triple-helix formation", "E": "Translation of pro-α chains"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 8-year-old boy is brought in by his mother due to complaints of a headache with diminished vision of his temporal field. It has been previously recorded that the patient has poor growth velocity. On imaging, a cystic calcified mass is noted above the sella turcica. From which of the following is this mass most likely derived?", "answer": "Oral ectoderm", "options": {"A": "Oral ectoderm", "B": "Cholesterol", "C": "Neuroectoderm", "D": "Neurohypophysis", "E": "Paraxial mesoderm"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man comes to the physician because of a 10-month history of crampy left lower extremity pain that is exacerbated by walking and relieved by rest. The pain is especially severe when he walks on an incline. He has a 20-year history of type 2 diabetes mellitus, for which he takes metformin. He has smoked 1 pack of cigarettes daily for 40 years. His blood pressure is 140/92 mm Hg. Physical examination shows dry and hairless skin over the left foot. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Intimal plaque in the posterior tibial artery", "options": {"A": "Osteophytic compression of the lumbar spinal canal", "B": "Thrombosing vasculitis of the popliteal artery", "C": "Intimal plaque in the posterior tibial artery", "D": "Fibrin clot in the left popliteal vein", "E": "Systemic hyperplastic arteriolosclerosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old African-American man comes to the physician for a follow-up examination after presenting with elevated blood pressure readings during his last visit. He has no history of major medical illness and takes no medications. He is 180 cm (5 ft 9 in) tall and weighs 68 kg (150 lb); BMI is 22 kg/m2. His pulse is 80/min and blood pressure is 155/90 mm Hg. Laboratory studies show no abnormalities. Which of the following is the most appropriate initial pharmacotherapy for this patient?", "answer": "Chlorthalidone", "options": {"A": "Valsartan", "B": "Metoprolol", "C": "Chlorthalidone", "D": "Aliskiren", "E": "Captopril"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 7-month-old boy is brought in to his pediatrician’s office due to concern for recurrent infections. The parents state that over the last 3-4 months, the boy has had multiple viral respiratory infections, along with a fungal pneumonia requiring hospitalization. Currently he is without complaints; however, the parents are concerned that he continues to have loose stools and is falling off of his growth curve. Newborn screening is not recorded in the patient’s chart. On exam, the patient’s temperature is 98.4°F (36.9°C), blood pressure is 108/68 mmHg, pulse is 90/min, and respirations are 12/min. The patient is engaging appropriately and is able to grasp, sit, and is beginning to crawl. However, the patient is at the 20th percentile for length and weight, when he was previously at the 50th percentile at 3 months of age. Further screening suggests that the patient has an autosomal recessive immunodeficiency associated with absent T-cells. Which of the following is also associated with this disease?", "answer": "Accumulation of deoxyadenosine", "options": {"A": "Accumulation of deoxyadenosine", "B": "Dysfunctional cell chemotaxis", "C": "Mutation in ATM DNA repair gene", "D": "Negative nitroblue-tetrazolium test", "E": "Nonfunctional common gamma chain"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old woman with a history of palpitations is being evaluated by a surgeon for epigastric pain. It is discovered that she has an epigastric hernia that needs repair. During her preoperative evaluation, she is ordered to receive lab testing, an electrocardiogram (ECG), and a chest X-ray. These screening studies are unremarkable except for her chest X-ray, which shows a 2 cm isolated pulmonary nodule in the middle lobe of the right lung. The nodule has poorly defined margins, and it shows a dense, irregular pattern of calcification. The patient is immediately referred to a pulmonologist for evaluation of the lesion. The patient denies any recent illnesses and states that she has not traveled outside of the country since she was a child. She has had no sick contacts or respiratory symptoms, and she does not currently take any medications. She does, however, admit to a 20-pack-year history of smoking. Which of the following is the most appropriate next step in evaluating this patient’s diagnosis with regard to the pulmonary nodule?", "answer": "Try to obtain previous chest radiographs for comparison", "options": {"A": "Obtain a contrast-enhanced CT scan of the chest", "B": "Send sputum for cytology", "C": "Order a positron emission tomography scan of the chest", "D": "Perform a flexible bronchoscopy with biopsy", "E": "Try to obtain previous chest radiographs for comparison"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "You are currently employed as a clinical researcher working on clinical trials of a new drug to be used for the treatment of Parkinson's disease. Currently, you have already determined the safe clinical dose of the drug in a healthy patient. You are in the phase of drug development where the drug is studied in patients with the target disease to determine its efficacy. Which of the following phases is this new drug currently in?", "answer": "Phase 2", "options": {"A": "Phase 1", "B": "Phase 2", "C": "Phase 3", "D": "Phase 4", "E": "Phase 0"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 37-year-old man is presented to the emergency department by paramedics after being involved in a serious 3-car collision on an interstate highway while he was driving his motorcycle. On physical examination, he is responsive only to painful stimuli and his pupils are not reactive to light. His upper extremities are involuntarily flexed with hands clenched into fists. The vital signs include temperature 36.1°C (97.0°F), blood pressure 80/60 mm Hg, and pulse 102/min. A non-contrast computed tomography (CT) scan of the head shows a massive intracerebral hemorrhage with a midline shift. Arterial blood gas (ABG) analysis shows partial pressure of carbon dioxide in arterial blood (PaCO2) of 68 mm Hg, and the patient is put on mechanical ventilation. His condition continues to decline while in the emergency department and it is suspected that this patient is brain dead. Which of the following results can be used to confirm brain death and legally remove this patient from the ventilator?", "answer": "CT scan", "options": {"A": "Electrocardiogram", "B": "More than a 30% decrease in pulse oximetry", "C": "Lumbar puncture and CSF culture", "D": "Electromyography with nerve conduction studies", "E": "CT scan"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old male presents to his primary care provider with an abnormal gait. He was hospitalized one week prior for acute cholecystitis and underwent a laparoscopic cholecystectomy. He received post-operative antibiotics via intramuscular injection. He recovered well and he was discharged on post-operative day #3. However, since he started walking after the operation, he noticed a limp that has not improved. On exam, his left hip drops every time he raises his left foot to take a step. In which of the following locations did this patient likely receive the intramuscular injection?", "answer": "Superomedial quadrant of the buttock", "options": {"A": "Anteromedial thigh", "B": "Superomedial quadrant of the buttock", "C": "Superolateral quadrant of the buttock", "D": "Inferomedial quadrant of the buttock", "E": "Inferolateral quadrant of the buttock"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old woman in the intensive care unit has had persistent oozing from the margins of wounds for 2 hours that is not controlled by pressure bandages. She was admitted to the hospital 13 hours ago following a high-speed motor vehicle collision. Initial focused assessment with sonography for trauma was negative. An x-ray survey showed opacification of the right lung field and fractures of multiple ribs, the tibia, fibula, calcaneus, right acetabulum, and bilateral pubic rami. Laboratory studies showed a hemoglobin concentration of 14.8 g/dL, leukocyte count of 10,300/mm3, platelet count of 175,000/mm3, and blood glucose concentration of 77 mg/dL. Infusion of 0.9% saline was begun. Multiple lacerations on the forehead and extremities were sutured, and fractures were stabilized. Repeat laboratory studies now show a hemoglobin concentration of 12.4 g/dL, platelet count of 102,000/mm3, prothrombin time of 26 seconds (INR=1.8), and activated partial thromboplastin time of 63 seconds. Which of the following is the next best step in management?", "answer": "Transfuse packed RBC, fresh frozen plasma, and platelet concentrate in a 1:1:1 ratio", "options": {"A": "Transfuse packed RBC, fresh frozen plasma, and platelet concentrate in a 1:1:1 ratio", "B": "Transfuse whole blood and administer vitamin K", "C": "Transfuse fresh frozen plasma and platelet concentrate in a 1:1 ratio", "D": "Transfuse packed RBC", "E": "Transfuse packed RBC and fresh frozen plasma in a 1:1 ratio"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 13-month-old boy with sickle cell anemia is brought to the emergency department because of continuous crying and severe left-hand swelling. His condition started 2 hours earlier without any preceding trauma. The child was given diclofenac syrup at home with no relief. The temperature is 37°C (98.6°F), blood pressure is 100/60 mm Hg, and pulse is 100/min. The physical examination reveals swelling and tenderness to palpation of the left hand. The hemoglobin level is 10.4 g/dL. Which of the following is the best initial step in management of this patient condition?", "answer": "Intravenous morphine", "options": {"A": "Intravenous morphine", "B": "Intravenous meperidine", "C": "Joint aspiration", "D": "Incentive spirometry", "E": "Magnetic resonance imaging (MRI) of the affected joint"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 31-year-old male comedian presents to your mental health clinic for a psychotherapy appointment. He is undergoing psychodynamic psychotherapy for depressive symptoms. During the therapy session, you discuss his job as a successful comedian and identify ways that he channels his emotions about his abusive childhood into comedy routines. Though he enjoys his job overall and idolizes some of his coworkers, he complains about most of them being “totally incompetent.” When you attempt to shift the discussion back to his childhood, he avoids eye contact and he tells you he “doesn’t want to talk about it anymore.” Which of the following is an immature defense mechanism exhibited by this patient?", "answer": "Splitting", "options": {"A": "Denial", "B": "Humor", "C": "Reaction formation", "D": "Splitting", "E": "Suppression"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying the physiological response during congestive heart failure exacerbations in patients with systolic heart failure. A hormone released by ventricular cardiomyocytes in response to increased wall stress is isolated from a patient's blood sample. The intracellular mechanism by which this hormone acts is most similar to the effect of which of the following substances?", "answer": "Nitric oxide", "options": {"A": "Nitric oxide", "B": "Human chorionic gonadotropin", "C": "Aldosterone", "D": "Angiotensin II", "E": "Platelet-derived growth factor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An asymptomatic 15-year-old high school wrestler with no family history of renal disease is completing his preseason physical exam. He submits a urine sample for a dipstick examination, which tests positive for protein. What is the next appropriate step in management?", "answer": "Repeat dipstick on a separate occasion", "options": {"A": "Repeat dipstick on a separate occasion", "B": "Urine culture", "C": "Renal ultrasound", "D": "24 hour urine collection", "E": "Spot urine-protein-to-creatinine ratio"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 44-year-old man is brought to the emergency department by his daughter for a 1-week history of right leg weakness, unsteady gait, and multiple falls. During the past 6 months, he has become more forgetful and has sometimes lost his way along familiar routes. He has been having difficulties operating simple kitchen appliances such as the dishwasher and the coffee maker. He has recently become increasingly paranoid, agitated, and restless. He has HIV, hypertension, and type 2 diabetes mellitus. His last visit to a physician was more than 2 years ago, and he has been noncompliant with his medications. His temperature is 37.2 °C (99.0 °F), blood pressure is 152/68 mm Hg, pulse is 98/min, and respirations are 14/min. He is somnolent and slightly confused. He is oriented to person, but not place or time. There is mild lymphadenopathy in the cervical, axillary, and inguinal areas. Neurological examination shows right lower extremity weakness with normal tone and no other focal deficits. Laboratory studies show:\nHemoglobin 9.2 g/dL\nLeukocyte count 3600/mm3\nPlatelet count 140,000/mm3\nCD4+ count 56/μL\nHIV viral load > 100,000 copies/mL\nSerum\nCryptococcal antigen negative\nToxoplasma gondii IgG positive\nAn MRI of the brain shows disseminated, nonenhancing white matter lesions with no mass effect. Which of the following is the most likely diagnosis?\"", "answer": "Progressive multifocal leukoencephalopathy", "options": {"A": "Vascular dementia", "B": "Neurocysticercosis", "C": "Progressive multifocal leukoencephalopathy", "D": "Primary CNS lymphoma", "E": "Cerebral toxoplasmosis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70 year-old man comes to the emergency department for sudden loss of vision in the right eye over the last 24 hours. He has noticed progressive bilateral loss of central vision over the last year. He has had difficulty reading his newspaper and watching his television. He has smoked 1 pack daily for 50 years. Ophthalmologic examination shows visual acuity of 20/60 in the left eye and 20/200 in the right eye. The pupils are equal and reactive to light. Tonometry reveals an intraocular pressure of 18 mm Hg in the right eye and 20 mm Hg in the left eye. Anterior segment exam is unremarkable. Slit-lamp examination shows subretinal fluid and small hemorrhage with grayish-green discoloration in the macular area in the right eye, and multiple drusen in the left eye with retinal pigment epithelial changes. Which of the following is the most appropriate initial treatment for the patient's illness?", "answer": "Ranibizumab", "options": {"A": "Etanercept", "B": "Thermal laser photocoagulation", "C": "Ranibizumab", "D": "Macular translocation surgery", "E": "Photodynamic therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old man presents to the emergency department with confusion. The patient is generally healthy, but his wife noticed him becoming progressively more confused as the day went on. The patient is not currently taking any medications and has no recent falls or trauma. His temperature is 102°F (38.9°C), blood pressure is 126/64 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for a confused man who cannot participate in a neurological exam secondary to his confusion. No symptoms are elicited with flexion of the neck and jolt accentuation of headache is negative. Initial laboratory values are unremarkable and the patient's chest radiograph and urinalysis are within normal limits. An initial CT scan of the head is unremarkable. Which of the following is the best next step in management?", "answer": "Acyclovir", "options": {"A": "Acyclovir", "B": "CT angiogram of the head and neck", "C": "MRI of the head", "D": "PCR of the cerebrospinal fluid", "E": "Vancomycin, ceftriaxone, ampicillin, and dexamethasone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 70-year-old man presents to his primary care physician for ear pain. The patient states he has had ear pain for the past several days that seems to be worsening. The patient lives in a retirement home and previously worked as a banker. The patient currently is active, swims every day, and drinks 3 to 4 glasses of whiskey at night. There have been multiple cases of the common cold at his retirement community. The patient has a past medical history of myocardial infarction, Alzheimer dementia, diabetes, hypertension, vascular claudication, and anxiety. His current medications include insulin, metformin, aspirin, metoprolol, lisinopril, and buspirone. His temperature is 99.5°F (37.5°C), blood pressure is 167/108 mmHg, pulse is 102/min, respirations are 17/min, and oxygen saturation is 98% on room air. Cardiopulmonary exam is within normal limits. HEENT exam is notable for tenderness over the left mastoid process. Abdominal and musculoskeletal exam are within normal limits. Which of the following is the best management for this patient's condition?", "answer": "Ciprofloxacin", "options": {"A": "Acetic acid drops", "B": "Amoxicillin", "C": "Amoxicillin/clavulanic acid", "D": "Ciprofloxacin", "E": "Observation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old woman with endometriosis comes to the physician because of bilateral flank pain and decreased urine output for 1-week. She has not had any fevers, chills, or dysuria. Physical examination shows several surgical scars on her abdomen. Laboratory studies show a serum creatinine concentration of 3.5 mg/dL. A CT scan of the abdomen shows numerous intra-abdominal adhesions, as well as dilatation of the renal pelvis and proximal ureters bilaterally. An increase in which of following is the most likely underlying mechanism of this patient's renal dysfunction?", "answer": "Hydrostatic pressure in the tubules", "options": {"A": "Hydrostatic pressure in the tubules", "B": "Osmotic pressure in the glomeruli", "C": "Hydrostatic pressure in the efferent arteriole", "D": "Osmotic pressure in the afferent arteriole", "E": "Osmotic pressure in the tubules"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old male visits the emergency room around 4 weeks after getting bitten by a bat during a cave diving trip. After cleansing the wound with water, the patient reports that he felt well enough not to seek medical attention immediately following his trip. He does endorse feeling feverish in the past week but a new onset of photophobia and irritability led him to seek help today. What would the post-mortem pathology report show if the patient succumbs to this infection?", "answer": "Negri bodies", "options": {"A": "Psammoma bodies", "B": "Pick bodies", "C": "Heinz bodies", "D": "Negri bodies", "E": "Howell-Jolly bodies"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old woman is brought to the emergency department by her husband who found her lying unconscious at home. He says that the patient has been complaining of progressively worsening weakness and confusion for the past week. Her past medical history is significant for hypertension, systemic lupus erythematosus, and trigeminal neuralgia. Her medications include metoprolol, valsartan, prednisone, and carbamazepine. On admission, blood pressure is 130/70 mm Hg, pulse rate is 100 /min, respiratory rate is 17/min, and temperature is 36.5°C (97.7ºF). She regained consciousness while on the way to the hospital but is still drowsy and disoriented. Physical examination is normal. Finger-stick glucose level is 110 mg/dl. Other laboratory studies show:\nNa+ 120 mEq/L (136—145 mEq/L)\nK+ 3.5 mEq/L (3.5—5.0 mEq/L)\nCI- 107 mEq/L (95—105 mEq/L)\nCreatinine 0.8 mg/dL (0.6—1.2 mg/dL)\nSerum osmolality 250 mOsm/kg (275—295 mOsm/kg)\nUrine Na+ 70 mEq/L  \nUrine osmolality 105 mOsm/kg  \nShe is admitted to the hospital for further management. Which of the following is the next best step in the management of this patient’s condition?", "answer": "Fluid restriction", "options": {"A": "Fluid restriction", "B": "Rapid resuscitation with hypertonic saline", "C": "Desmopressin", "D": "Lithium", "E": "Tolvaptan"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old primigravid woman at 12 weeks' gestation comes to the physician because of several hours of abdominal cramping and passing of large vaginal blood clots. Her temperature is 36.8°C (98.3°F), pulse is 75/min, and blood pressure is 110/65 mmHg. The uterus is consistent in size with a 12-week gestation. Speculum exam shows an open cervical os and blood clots within the vaginal vault. Transvaginal ultrasound shows an empty gestational sac. The patient is worried about undergoing invasive procedures. Which of the following is the most appropriate next step in management?", "answer": "Expectant management", "options": {"A": "Dilation and curettage", "B": "Expectant management", "C": "Methotrexate therapy", "D": "Serial beta-hCG measurement", "E": "Oxytocin therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A surgeon is interested in studying how different surgical techniques impact the healing of tendon injuries. In particular, he will compare 3 different types of suture repairs biomechanically in order to determine the maximum load before failure of the tendon 2 weeks after repair. He collects data on maximum load for 90 different repaired tendons from an animal model. Thirty tendons were repaired using each of the different suture techniques. Which of the following statistical measures is most appropriate for analyzing the results of this study?", "answer": "ANOVA", "options": {"A": "ANOVA", "B": "Chi-squared", "C": "Pearson r coefficient", "D": "Student t-test", "E": "Wilcoxon rank sum"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old man comes to the physician because of a 2-month history of generalized fatigue. On examination, he appears pale. He also has multiple pinpoint, red, nonblanching spots on his extremities. His spleen is significantly enlarged. Laboratory studies show a hemoglobin concentration of 8.3 g/dL, a leukocyte count of 81,000/mm3, and a platelet count of 35,600/mm3. A peripheral blood smear shows immature cells with large, prominent nucleoli and pink, elongated, needle-shaped cytoplasmic inclusions. Which of the following is the most likely diagnosis?", "answer": "Acute myelogenous leukemia", "options": {"A": "Myelodysplastic syndrome", "B": "Acute lymphoblastic leukemia", "C": "Acute myelogenous leukemia", "D": "Chronic myelogenous leukemia", "E": "Hairy cell leukemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is studying the effect that mutations in different parts of the respiratory tract have on susceptibility to infection. A mutation in the gene encoding for the CD21 protein is induced in a sample of cells obtained from the nasopharyngeal epithelium. This mutation is most likely to prevent infection with which of the following viruses?", "answer": "Epstein-Barr virus", "options": {"A": "Rhinovirus", "B": "Epstein-Barr virus", "C": "Human immunodeficiency virus", "D": "Cytomegalovirus", "E": "Parvovirus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old woman presents to her primary care physician for gradually worsening pain in both wrists that began several months ago. The pain originally did not bother her, but it has recently begun to affect her daily functioning. She states that the early morning stiffness in her hands is severe and has made it difficult to tend to her rose garden. She occasionally takes ibuprofen for the pain, but she says this does not really help. Her medical history is significant for diabetes mellitus and major depressive disorder. She is currently taking insulin, sertraline, and a daily multivitamin. The vital signs include: blood pressure 126/84 mm Hg, heart rate 82/min, and temperature 37.0°C (98.6°F). On physical exam, her wrists and metacarpophalangeal joints are swollen, tender, erythematous, and warm to the touch. There are no nodules or vasculitic lesions. Which of the following antibodies would be most specific to this patient’s condition?", "answer": "Anti-cyclic citrullinated peptide", "options": {"A": "Anti-Ro", "B": "Rheumatoid factor", "C": "Anti-Scl-70", "D": "c-ANCA", "E": "Anti-cyclic citrullinated peptide"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old man comes to the physician for a follow-up evaluation for chronic lower back pain. He has back stiffness that lasts all morning and slowly improves throughout the day. He has tried multiple over-the-counter medications, including ibuprofen, without any improvement in his symptoms. Physical examination shows tenderness over the iliac crest bilaterally and limited range of motion of the lumbar spine with forward flexion. The results of HLA-B27 testing are positive. An x-ray of the lumbar spine shows fusion of the lumbar vertebrae and sacroiliac joints. The physician plans to prescribe a new medication but first orders a tuberculin skin test to assess for the risk of latent tuberculosis reactivation. Inhibition of which of the following is the most likely primary mechanism of action of this drug?", "answer": "TNF-α", "options": {"A": "Inosine monophosphate dehydrogenase", "B": "TNF-α", "C": "NF-κB", "D": "Calcineurin", "E": "mTOR kinase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old man is brought to the emergency department by his wife because of bizarre and agitated behavior for the last 6 weeks. He thinks that the NSA is spying on him and controlling his mind. His wife reports that the patient has become withdrawn and at times depressed for the past 3 months. He lost his job because he stopped going to work 4 weeks ago. Since then, he has been working on an invention that will block people from being able to control his mind. Physical and neurologic examinations show no abnormalities. On mental status examination, he is confused and suspicious with marked psychomotor agitation. His speech is disorganized and his affect is labile. Which of the following is the most likely diagnosis?", "answer": "Schizophreniform disorder", "options": {"A": "Delusional disorder", "B": "Schizophreniform disorder", "C": "Schizophrenia", "D": "Brief psychotic disorder", "E": "Schizotypal personality disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 28-year-old man presents to his primary care provider because of shortness of breath, cough, and wheezing. He reports that in high school, he occasionally had shortness of breath and would wheeze after running. His symptoms have progressively worsened over the past 6 months and are now occurring daily. He also finds himself being woken up from sleep by his wheeze approximately 3 times a week. His medical history is unremarkable. He denies tobacco use or excessive alcohol consumption. His temperature is 37.1°C (98.8°F), blood pressure is 121/82 mm Hg, and heart rate is 82/min. Physical examination is remarkable for expiratory wheezing bilaterally. Spirometry shows an FEV1 of 73% of predicted, which improves by 19% with albuterol. In addition to a short-acting beta-agonist as needed, which of the following is the most appropriate therapy for this patient?", "answer": "A low-dose inhaled corticosteroid and a long-acting beta-agonist", "options": {"A": "A low-dose inhaled corticosteroid alone", "B": "A long-acting beta-agonist alone", "C": "A low-dose inhaled corticosteroid and a long-acting beta-agonist", "D": "A medium-dose inhaled corticosteroid and a long-acting beta-agonist", "E": "A high-dose inhaled corticosteroid and a long-acting beta-agonist"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old woman comes to the physician because of a dry cough and worsening shortness of breath with exertion for the past 6 months. She used to go running three times each week but had to stop because of decreased exercise tolerance and pain in the bilateral ankles. Two months ago, she was in Nigeria for several weeks to visit her family. She is allergic to cats and pollen. She has smoked one pack of cigarettes daily for the past 17 years. Her vital signs are within normal limits. Examination shows multiple 1.5- to 2-cm, nontender lymph nodes in the axillae. A few crackles are heard on auscultation of the chest. Her serum calcium concentration is 11.7 mg/dL. An x-ray of the chest shows enlarged hilar lymph nodes bilaterally and reticular opacities in both lungs. Which of the following is the most likely cause of these findings?", "answer": "Granulomatous inflammation", "options": {"A": "Necrotizing inflammation", "B": "Granulomatous inflammation", "C": "Neoplastic transformation", "D": "Viral infection", "E": "Air trapping"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 78-year-old male presents to the emergency department after passing out. His wife reports that she and the patient were walking their dog when he suddenly lost consciousness. On physical exam, he has a loud crescendo-decrescendo systolic murmur and is subsequently diagnosed with severe aortic stenosis. The patient undergoes open aortic valve replacement and has an uncomplicated postoperative course. His sternal wound drain is pulled for low output on post-operative day three. On post-operative day five, the patient complains of pain during deep inspiration and retrosternal chest pain. His temperature is 101.7°F (38.7°C), blood pressure is 125/81 mmHg, pulse is 104/min, and respirations are 18/min. On physical exam, the patient is tender to palpation around his sternal wound, and there is erythema around the incision without dehiscence. His chest radiograph shows a widened mediastinum with a small pleural effusion on the left. CT angiography shows stranding in the subcutaneous tissue and a fluid collection below the sternum.\n\nWhich of the following is the best next step in management?", "answer": "Intravenous antibiotics and debridement of surgical wound", "options": {"A": "Placement of a left-sided chest tube", "B": "Surgical repair of esophageal perforation", "C": "Surgical repair of aortic injury", "D": "Intravenous antibiotics and observation", "E": "Intravenous antibiotics and debridement of surgical wound"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old G3P3 presents with an 8-year-history of back pain, perineal discomfort, difficulty urinating, recurrent malaise, and low-grade fevers. These symptoms have recurred regularly for the past 5–6 years. She also says that there are times when she experiences a feeling of having a foreign body in her vagina. With the onset of symptoms, she was evaluated by a physician who prescribed her medications after a thorough examination and recommended a vaginal pessary, but she was non-compliant. She had 3 vaginal deliveries She has been menopausal since 51 years of age. She does not have a history of malignancies or cardiovascular disease. She has type 2 diabetes mellitus that is controlled with diet and metformin. Her vital signs include: blood pressure 110/60 mm Hg, heart rate 91/min, respiratory rate 13/min, and temperature 37.4℃ (99.3℉). On physical examination, there is bilateral costovertebral angle tenderness. The urinary bladder is non-palpable. The gynecologic examination reveals descent of the cervix to the level of the introitus. A Valsalva maneuver elicits uterine procidentia. Which pathology is most likely to be revealed by imaging in this patient?", "answer": "Hydronephrosis", "options": {"A": "Renal tumor", "B": "Hydronephrosis", "C": "Urinary bladder polyp", "D": "Renal calculi", "E": "Renal cyst"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 9-year-old boy is brought to the emergency department for the evaluation of diarrhea and vomiting for the last 2 days. During this period, he has had about 12 watery, non-bloody bowel movements and has vomited three times. He came back from a trip to India 3 days ago, where he and his family were visiting relatives. He has not been able to eat anything since the symptoms started. The patient has not urinated since yesterday. He appears pale. His temperature is 38°C (100.4°F), pulse is 106/min, and blood pressure is 96/60 mm Hg. Examination shows dry mucous membranes. The abdomen is soft with no organomegaly. Bowel sounds are hyperactive. Laboratory studies show:\nHemoglobin 13 g/dL\nSerum\nNa+ 148 mEq/L\nCl- 103 mEq/L\nK+ 3.7 mEq/L\nHCO3- 19 mEq/L\nUrea nitrogen 80 mg/dL\nGlucose 90 mg/dL\nCreatinine 2 mg/dL\nIntravenous fluid resuscitation is begun. Which of the following is the most likely cause of this patient's abnormal renal laboratory findings?\"", "answer": "Decreased renal perfusion", "options": {"A": "Decreased renal perfusion", "B": "Renal artery stenosis", "C": "IgA complex deposition", "D": "Glomerulonephritis", "E": "Urinary tract obstruction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 25-year-old man comes to the physician because of a 4-day history of fever, joint and body pain, diffuse headache, and pain behind the eyes. This morning he noticed that his gums bled when he brushed his teeth. He returned from a backpacking trip to the Philippines 4 days ago. His temperature is 39.4°C (103.0°F). Physical examination shows a diffuse maculopapular rash. His leukocyte count is 3,200/mm3 and platelet count is 89,000/mm3. Further evaluation shows increased serum levels of a flavivirus. Which of the following is the most likely causal pathogen?", "answer": "Dengue virus", "options": {"A": "Chikungunya virus", "B": "Ebola virus", "C": "Hanta virus", "D": "Lassa virus", "E": "Dengue virus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "You are reviewing the protocol for a retrospective case-control study investigating risk factors for mesothelioma among retired factory workers. 100 cases of mesothelioma and 100 age and sex matched controls are to be recruited and interviewed about their exposure to industrial grade fiberglass by blinded interviewers. The investigators' primary hypothesis is that cases of mesothelioma will be more likely to have been exposed to industrial grade fiberglass. The design of this study is most concerning for which type of bias?", "answer": "Recall bias", "options": {"A": "Interviewer bias", "B": "Recall bias", "C": "Observer bias", "D": "Lead-time bias", "E": "This study design is free of potential bias"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old man presents to his primary care provider complaining of abdominal pain. The patient reports a dull pain that has been present for 4 weeks now. The patient states that the pain is located to his right upper quadrant and does not change with eating. The patient denies any alcohol or illicit substance use, stating that he is meticulous about eating healthy since he is a professional bodybuilder. The patient reports no history of malignancy. On exam, the patient's temperature is 98.2°F (36.8°C), blood pressure is 130/86 mmHg, pulse is 60/min, and respirations are 12/min. The patient has an athletic build, and his exam is unremarkable for any palpable mass or abdominal tenderness. On further questioning, the patient does endorse a 5-year history of using anabolic steroids for bodybuilding. Imaging demonstrates an enhancing liver nodule. Which of the following is the most likely histopathologic finding of this patient’s disease?", "answer": "Sheets of normal hepatocytes without portal tracts or central veins", "options": {"A": "Columnar cells with acinar structures", "B": "Hemorrhagic nests with atypical endothelial cells", "C": "Hypervascular lesion lined by normal endothelial cells", "D": "Multifocal tumor with multiple layers of hepatocytes with hemorrhage and necrosis", "E": "Sheets of normal hepatocytes without portal tracts or central veins"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 48-year-old man comes to the physician because of a 3-month history of worsening shortness of breath and cough productive of frothy, whitish sputum. One year ago, he had a similar episode lasting 6 months. He has smoked a pack of cigarettes daily for 25 years. Physical examination shows bluish discoloration of the tongue and lips. Scattered expiratory wheezing and rhonchi are heard throughout both lung fields. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Increased serum hematocrit", "options": {"A": "Increased pulmonary capillary wedge pressure", "B": "Normal FEV1", "C": "Increased FEV1/FVC ratio", "D": "Increased serum hematocrit", "E": "Increased diffusing capacity for carbon monoxide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old woman presents to the emergency department after she was found agitated and screaming for help in the middle of the street. She says she also has dizziness and tingling in the lips and hands. Her past medical history is relevant for general anxiety disorder, managed medically with paroxetine. At admission, her pulse is 125/min, respiratory rate is 25/min, and body temperature is 36.5°C (97.7°C). Physical examination is unremarkable. An arterial blood gas sample is taken. Which of the following results would you most likely expect to see in this patient?", "answer": "pH: increased, HCO3- : decreased, Pco2: decreased", "options": {"A": "pH: increased, HCO3- : decreased, Pco2: decreased", "B": "pH: decreased, HCO3- : decreased, Pco2: decreased", "C": "pH: decreased, HCO3- : increased, Pco2: increased", "D": "pH: increased, HCO3- : increased, Pco2: increased", "E": "pH: normal, HCO3- : increased, Pco2: increased"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman presents to a medical office with complaints of fatigue, weight loss, and low-grade fever for 1 week. She noticed bleeding spots on her feet this morning. The past medical history is significant for a recent dental appointment. She is a non-smoker and does not drink alcohol. She does not currently take any medications. On examination, the vital signs include temperature 37.8°C (100.0°F), blood pressure 138/90 mm Hg, respirations 21/min, and pulse 87/min. Cardiac auscultation reveals a pansystolic murmur in the mitral area with radiation to the right axilla. Laboratory studies show hemoglobin levels of 17.2 g/dL, erythrocyte sedimentation rate (ESR) of 25 mm/h, and a white blood cell (WBC) count of 12,000 cells/mm3. An echocardiogram (ECG) reveals valvular vegetations on the mitral valve with mild regurgitation. Blood samples are sent for bacterial culture. Empiric antibiotic therapy is initiated with ceftriaxone and vancomycin. The blood cultures most likely will yield the growth of which of the following organisms?", "answer": "Streptococcus viridans", "options": {"A": "Staphylococcus aureus", "B": "Actinomyces israelii", "C": "Streptococcus viridans", "D": "Group B Streptococcus", "E": "Coxiella burnetii"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old G2P2 presents to her gynecologist to discuss the results of her diagnostic tests. She has no  current complaints or concurrent diseases. She underwent a tubal ligation after her last pregnancy. Her last Pap smear showed a high-grade squamous intraepithelial lesion and a reflex HPV test was positive. Colposcopic examination reveals areas of thin acetowhite epithelium with diffuse borders and fine punctation. The biopsy obtained from the suspicious areas shows CIN 1. Which of the following is an appropriate next step in the management of this patient?", "answer": "Loop electrosurgical excision procedure", "options": {"A": "Cryoablation", "B": "Loop electrosurgical excision procedure", "C": "Cold-knife conization", "D": "Test for type 16 and 18 HPV", "E": "Repeat cytology and HPV co-testing in 6 months"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old man comes to the physician for a follow-up examination after having been diagnosed with stage II adenocarcinoma of the left lower lung lobe without evidence of distant metastases 1 week ago following an evaluation for a chronic cough. He has hypertension and type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for the past 40 years. His current medications include metformin, sitagliptin, and enalapril. He is 177 cm (5 ft 10 in) tall and weighs 65 kg (143 lb); BMI is 20.7 kg/m2. He appears lethargic. Vital signs are within normal limits. Pulse oximetry shows an oxygen saturation of 98%. Examination shows inspiratory wheezing at the left lung base. The remainder of the examination shows no abnormalities. A complete blood count and serum concentrations of electrolytes, creatinine, glucose, and liver enzymes are within the reference range. Spirometry shows an FEV1 of 1.6 L. The diffusing lung capacity for carbon monoxide (DLCO) is 66% of predicted. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Schedule lobectomy", "options": {"A": "Schedule lobectomy", "B": "Radiation therapy", "C": "Schedule a wedge resection", "D": "Administer cisplatin and etoposide", "E": "Administer cisplatin and vinorelbine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An otherwise healthy 23-year-old man comes to the physician because of a 3-day history of mild persistent bleeding from the site of a tooth extraction. He has no prior history of medical procedures or surgeries and no history of easy bruising. He appears well. Vital signs are within normal limits. Laboratory studies show:\nHemoglobin 12.4 g/dL\nPlatelets 200,000/mm3\nSerum\nProthrombin time 25 seconds\nPartial thromboplastin time (activated) 35 seconds\nDeficiency of which of the following coagulation factors is the most likely cause of this patient’s condition?\"", "answer": "Factor VII", "options": {"A": "Factor VII", "B": "Factor V", "C": "Factor II", "D": "Factor XIII", "E": "Factor X"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 64-year-old man presents to his primary care clinic for a regular checkup. He reports feeling depressed since his wife left him 6 months prior and is unable to recall why she left him. He denies any sleep disturbance, change in his eating habits, guilt, or suicidal ideation. His past medical history is notable for hypertension, gout, and a myocardial infarction five years ago. He takes lisinopril, aspirin, metoprolol, and allopurinol. He has a 50 pack-year smoking history and was previously a heroin addict but has not used in over 20 years. He drinks at least 6 beers per day. His temperature is 98.6°F (37°C), blood pressure is 155/95 mmHg, pulse is 100/min, and respirations are 18/min. He appears somewhat disheveled, inattentive, and smells of alcohol. During his prior visits, he has been well-groomed and attentive. When asked what year it is and who the president is, he confidently replies “1999” and “Jimmy Carter.” He says his son’s name is “Peter” when it is actually “Jake.” This patient likely has a lesion in which of the following brain regions?", "answer": "Anterior pillars of the fornix", "options": {"A": "Anterior pillars of the fornix", "B": "Arcuate fasciculus", "C": "Dorsal hippocampus", "D": "Parahippocampal gyrus", "E": "Posterior pillars of the fornix"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old man comes to the physician's office due to a 3-week history of fatigue and a rash, along with the recent development of joint pain that has moved from his knee to his elbows. The patient reports going camping last month but denies having been bitten by a tick. His past medical history is significant for asthma treated with an albuterol inhaler. His pulse is 54/min and blood pressure is 110/72. Physical examination reveals multiple circular red rings with central clearings on the right arm and chest. There is a normal range of motion in all joints and 5/5 strength bilaterally in the upper and lower extremities. Without proper treatment, the patient is at highest risk for which of the following complications?", "answer": "Cranial nerve palsy", "options": {"A": "Cranial nerve palsy", "B": "Glomerular damage", "C": "Heart valve stenosis", "D": "Bone marrow failure", "E": "Liver capsule inflammation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 58-year-old man presents to the emergency department with severe chest pain and uneasiness. He says that symptoms onset acutely half an hour ago while he was watching television. He describes the pain as being 8/10 in intensity, sharp in character, localized to the center of the chest and retrosternal, and radiating to the back and shoulders. The patient denies any associated change in the pain with breathing or body position. He says he has associated nausea but denies any vomiting. He denies any recent history of fever, chills, or chronic cough. His past medical history is significant for hypertension, hyperlipidemia, and diabetes mellitus for which he takes lisinopril, hydrochlorothiazide, simvastatin, and metformin. He reports a 30-pack-year smoking history and has 1–2 alcoholic drinks during the weekend. Family history is significant for hypertension, hyperlipidemia, and an ST elevation myocardial infarction in his father and paternal uncle. His blood pressure is 220/110 mm Hg in the right arm and 180/100 mm Hg in the left arm. On physical examination, the patient is diaphoretic. Cardiac exam reveals a grade 2/6 diastolic decrescendo murmur loudest over the left sternal border. Remainder of the physical examination is normal. The chest radiograph shows a widened mediastinum. The electrocardiogram (ECG) reveals non-specific ST segment and T wave changes. Intravenous morphine and beta-blockers are started. Which of the following is the most likely diagnosis in this patient?", "answer": "Aortic dissection", "options": {"A": "Aortic dissection", "B": "Pulmonary embolism", "C": "Acute myocardial infarction", "D": "Myocarditis", "E": "Aortic regurgitation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A study on cholesterol levels is performed. There are 1000 participants. It is determined that in this population, the mean LDL is 200 mg/dL with a standard deviation of 50 mg/dL. If the population has a normal distribution, how many people have a cholesterol less than 300 mg/dL?", "answer": "975", "options": {"A": "680", "B": "840", "C": "950", "D": "975", "E": "997"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2-year-old boy is brought to the physician by his mother for evaluation of recurrent infections and easy bruising. He has been hospitalized 3 times for severe skin and respiratory infections, which responded to treatment with antibiotics. Examination shows sparse silvery hair. The skin is hypopigmented and there are diffuse petechiae. Laboratory studies show a hemoglobin concentration of 8 g/dL, leukocyte count of 3000/mm3, and platelet count of 45,000/mm3. A peripheral blood smear shows giant cytoplasmic granules in granulocytes and platelets. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Defective lysosomal trafficking regulator gene", "options": {"A": "Defective CD40 ligand", "B": "Defective tyrosine kinase gene", "C": "WAS gene mutation", "D": "Defective NADPH oxidase", "E": "Defective lysosomal trafficking regulator gene"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "To protect against a potentially deadly infection, a 19-year-old female receives a vaccine containing capsular polysaccharide. This vaccine will stimulate her immune system to produce antibodies against which organism?", "answer": "Neisseria meningitidis", "options": {"A": "Measles", "B": "Smallpox", "C": "Neisseria meningitidis", "D": "Corynebacterium diphtheriae", "E": "Clostridium tetani"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-year-old African American boy presents with fever, jaundice, normochromic normocytic anemia and generalized bone pain. He has a history of similar recurrent bone pain in the past which was partially relieved by analgesics. His vital signs include: blood pressure 120/70 mm Hg, pulse 105/min, respiratory rate 40/min, temperature 37.7℃ (99.9℉), and oxygen saturation 98% in room air. On physical examination, the patient is in severe distress due to pain. He is pale, icteric and dehydrated. His abdomen is full, tense and some degree of guarding is present. Musculoskeletal examination reveals diffuse tenderness of the legs and arms. A complete blood count reveals the following:\nHb 6.5g/dL\nHct 18%\nMCV 82.3 fL\nPlatelet 465,000/µL\nWBC 9800/µL\nReticulocyte 7%\nTotal bilirubin 84 g/dL\nA peripheral blood smear shows target cells, elongated cells, and erythrocytes with nuclear remnants. Results from Hb electrophoresis are shown in the exhibit (see image). Which of the following is the most likely cause of this patient’s condition?", "answer": "Sickle cell disease", "options": {"A": "Sickle cell trait", "B": "Sickle cell disease", "C": "Von-Gierke’s disease", "D": "G6PD deficiency", "E": "HbC"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 69-year-old woman is admitted to the hospital with substernal, crushing chest pain. She is emergently moved to the cardiac catheterization lab where she undergoes cardiac angiography. Angiography reveals that the diameter of her left anterior descending artery (LAD) is 50% of normal. If her blood pressure, LAD length, and blood viscosity have not changed, which of the following represents the most likely change in LAD flow from baseline?", "answer": "Decreased by 93.75%", "options": {"A": "Increased by 6.25%", "B": "Increased by 25%", "C": "Decreased by 93.75%", "D": "Decreased by 87.5%", "E": "Decreased by 25%"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 63-year-old man comes to the physician because of generalized fatigue and malaise for 2 months. He has been unable to engage in his daily activities. Three months ago, he was treated for a urinary tract infection with trimethoprim-sulfamethoxazole. He has hypertension, asthma, and chronic lower back pain. Current medications include hydrochlorothiazide, an albuterol inhaler, naproxen, and an aspirin-caffeine combination. Vital signs are within normal limits. Examination shows conjunctival pallor. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 9.1 g/dL\nLeukocyte count 8,900/mm3\nErythrocyte sedimentation rate 13 mm/h\nSerum\nNa+ 136 mEq/L\nK+ 4.8 mEq/L\nCl- 102 mEq/L\nUrea nitrogen 41 mg/dL\nGlucose 70 mg/dL\nCreatinine 2.4 mg/dL\nCalcium 9.8 mg/dL\nUrine\nProtein 1+\nBlood 1+\nRBCs none\nWBCs 8–9/hpf\nBacteria none\nUrine cultures are negative. Ultrasound shows shrunken kidneys with irregular contours and papillary calcifications. Which of the following is the most likely underlying mechanism of this patient's renal failure?\"", "answer": "Inhibition of prostacyclin production", "options": {"A": "Inhibition of prostacyclin production", "B": "Excess amount of light chain production", "C": "Precipitation of drugs within the renal tubules", "D": "MUC1 gene mutation", "E": "Hypersensitivity reaction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old woman presents to the clinic with a 3-month history of shortness of breath that worsens on exertion. She also complains of chronic cough that has lasted for 10 years. Her symptoms are worsened even with light activities like climbing up a flight of stairs. She denies any weight loss, lightheadedness, or fever. Her medical history is significant for hypertension, for which she takes amlodipine daily. She has a 70-pack-year history of cigarette smoking and drinks 3–4 alcoholic beverages per week. Her blood pressure today is 128/84 mm Hg. A chest X-ray shows flattening of the diaphragm bilaterally. Physical examination is notable for coarse wheezing bilaterally. Which of the following is likely to be seen with pulmonary function testing?", "answer": "Decreased FEV1: FVC and increased total lung capacity", "options": {"A": "Increased FEV1: FVC and decreased total lung capacity", "B": "Decreased FEV1: FVC and increased total lung capacity", "C": "Increased FEV1: FVC and normal total lung capacity", "D": "Decreased FEV1: FVC and decreased total lung capacity", "E": "Normal FEV1: FVC and decreased total lung capacity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old male presents to clinic complaining that he is not sleeping well because he has to get up from bed to urinate multiple times throughout the night. He says that he strains to void, has terminal dribbling, and has urinary urgency. Past medical history is significant for orthostatic hypotension. On digital rectal exam, you note symmetric firm enlargement of the prostate. Free Prostate-Specific-Antigen (PSA) level is 4.6 ng/mL. Before you finish your physical exam, the patient asks if there is anything you can do for his male-pattern baldness. What is the mechanism of action of the drug that would pharmacologically treat this patient’s urinary issues and his male-pattern baldness?", "answer": "5-alpha reductase inhibition", "options": {"A": "Phosphodiesterase-5 inhibition", "B": "Alpha-1 blockade", "C": "Squalene epoxidase inhibition", "D": "5-alpha reductase inhibition", "E": "17,20-desmolase inhibition"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 75-year-old man presents to the emergency department after an episode of syncope while walking outside with his wife. His wife states that he suddenly appeared pale and collapsed to the ground. She says he remained unconscious for 1 minute. He says noticed a fluttering in his chest and excessive sweating before the episode. He has type 2 diabetes mellitus, essential hypertension, and chronic stable angina. He has not started any new medications in the past few months. Vital signs reveal: temperature 37.0°C (98.6°F), blood pressure 135/72 mm Hg, and pulse 72/min. Physical examination is unremarkable. ECG shows an old bifascicular block. Echocardiogram and 24-hour Holter monitoring are normal. Which of the following is the best next step in the evaluation of this patient’s condition?", "answer": "Continuous loop recorder", "options": {"A": "Electroencephalography (EEG)", "B": "Tilt-table test", "C": "Continuous loop recorder", "D": "Valsalva maneuver", "E": "Cardiac enzymes"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Two days after undergoing emergency cardiac catherization for myocardial infarction, a 68-year-old woman has pain in her toes. During the intervention, she was found to have an occluded left anterior descending artery and 3 stents were placed. She has hypertension, hypercholesterolemia, and coronary artery disease. Prior to admission, her medications were metoprolol, enalapril, atorvastatin, and aspirin. Her temperature is 37.3°C (99.1°F), pulse is 93/min, and blood pressure is 115/78 mm Hg. Examination shows discoloration of the toes of both feet. A photograph of the right foot is shown. The lesions are cool and tender to palpation. The rest of the skin on the feet is warm; femoral and pedal pulses are palpable bilaterally. This patient is at increased risk for which of the following conditions?", "answer": "Acute kidney injury", "options": {"A": "Acute kidney injury", "B": "Lipodermatosclerosis", "C": "Basophilia", "D": "Permanent flexion contracture", "E": "Migratory thrombophlebitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A novel PET radiotracer is being evaluated for its ability to aid in the diagnosis of Alzheimer’s disease (AD). The study decides to use a sample size of 1,000 patients, and half of the patients enrolled have AD. In the group of patients with AD, 400 are found positive on the novel type of PET imaging examination. In the control group, 50 are found positive. What is the PPV of this novel exam?", "answer": "400 / (400+50)", "options": {"A": "400 / (400+100)", "B": "450 / (450 + 50)", "C": "400 / (400+50)", "D": "400 / (400 + 150)", "E": "450 / (450 + 100)"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl is brought in by her mother due to rapid weight loss over the past month. The patient says she has been having episodes of diarrhea, which she attributes to laxatives she takes regularly to keep her weight down. She also says she has not had her period yet. The patient’s mother adds that the patient has been underperforming at school and acting very strangely at home. Her current BMI is 16.8 kg/m2. On physical examination, the skin on her limbs and around her neck is inflamed and erythematous. Her tongue is bright red and smooth. She states that over the last 2 weeks, she has been eating nothing but small portions of fruit. She is diagnosed with a vitamin deficiency. Which of the following statements is true about the vitamin most likely deficient in this patient?", "answer": "Synthesis requires vitamin B2 and B6", "options": {"A": "It is derived from tyrosine", "B": "Synthesis requires vitamin B1 and B6", "C": "It is used to treat hypertension", "D": "Synthesis requires vitamin B2 and B6", "E": "It increases the GI absorption of iron"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old man is admitted to the burn unit after he was brought to the emergency room following an accidental fire in his house. His past medical history is unknown due to his current clinical condition. Currently, his blood pressure is 75/40 mmHg, pulse rate is 140/min, and respiratory rate is 17/min. The patient is subsequently intubated and started on aggressive fluid resuscitation. A Swan-Ganz catheter is inserted to clarify his volume status. Which of the following hemodynamic parameters would you expect to see in this patient?", "answer": "Cardiac output: ↓, systemic vascular resistance: ↑, pulmonary artery wedge pressure: ↓", "options": {"A": "Cardiac output: ↓, systemic vascular resistance: ↔, pulmonary artery wedge pressure: ↔", "B": "Cardiac output: ↑, systemic vascular resistance: ↑, pulmonary artery wedge pressure: ↔", "C": "Cardiac output: ↓, systemic vascular resistance: ↑, pulmonary artery wedge pressure: ↓", "D": "Cardiac output: ↑, systemic vascular resistance: ↓, pulmonary artery wedge pressure: ↔", "E": "Cardiac output: ↔, systemic vascular resistance: ↔, pulmonary artery wedge pressure: ↔"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old woman volunteers for a study on respiratory physiology. Pressure probes A and B are placed as follows:\nProbe A: between the parietal and visceral pleura\nProbe B: within the cavity of an alveoli\nThe probes provide a pressure reading relative to atmospheric pressure. To obtain a baseline reading, she is asked to sit comfortably and breathe normally. Which of the following sets of values will most likely be seen at the end of inspiration?", "answer": "Probe A: -6 mm Hg; Probe B: 0 mm Hg", "options": {"A": "Probe A: 0 mm Hg; Probe B: -1 mm Hg", "B": "Probe A: -4 mm Hg; Probe B: 0 mm Hg", "C": "Probe A: -4 mm Hg; Probe B: -1 mm Hg", "D": "Probe A: -6 mm Hg; Probe B: 0 mm Hg", "E": "Probe A: -6 mm Hg; Probe B: -1 mm Hg"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 16-year-old man presents to the emergency department with a 2-hour history of sudden-onset abdominal pain. He was playing football when his symptoms started. The patient’s past medical history is notable only for asthma. Social history is notable for unprotected sex with 4 women in the past month. His temperature is 99.3°F (37.4°C), blood pressure is 120/88 mmHg, pulse is 117/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is noted for a non-tender abdomen. Testicular exam reveals a right testicle which is elevated with a horizontal lie and the scrotum is neither swollen nor discolored. Which of the following is the most likely diagnosis?", "answer": "Testicular torsion", "options": {"A": "Appendicitis", "B": "Epididymitis", "C": "Seminoma", "D": "Testicular torsion", "E": "Traumatic urethral injury"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Please refer to the summary above to answer this question\nWhich of the following is the most appropriate next step in management?\"\n\"Patient Information\nAge: 23 years\nGender: F, self-identified\nEthnicity: unspecified\nSite of Care: office\nHistory\nReason for Visit/Chief Concern: “I can't run anymore because my knee hurts.”\nHistory of Present Illness:\n2-day history of right knee pain\npain is localized “somewhere under the kneecap”\npain is achy; rated 5/10; increases to 8/10 with prolonged sitting\nreports an occasional “popping” sound and sensation when she rises from a seated position\nno history of trauma to the knee\nPast Medical History:\nright clavicular fracture 2 years ago, treated with a shoulder sling\nMedications:\nmultivitamin\nAllergies:\nno known drug allergies\nPsychosocial History:\ndoes not smoke\ndrinks up to three glasses of wine weekly\nPhysical Examination\nTemp Pulse Resp BP O2 Sat Ht Wt BMI\n37°C\n(98.6°F)\n65/min 15/min 108/62 mm Hg –\n173 cm\n(5 ft 8 in)\n54 kg\n(119 lb)\n18 kg/m2\nAppearance: no acute distress\nPulmonary: clear to auscultation\nCardiac: regular rate and rhythm; normal S1 and S2; no murmurs, rubs, or gallops\nAbdominal: thin; no tenderness, guarding, masses, bruits, or hepatosplenomegaly\nExtremities: no joint erythema, edema, or warmth; dorsalis pedis, radial, and femoral pulses intact\nMusculoskeletal: diffuse tenderness to palpation over the right anterior knee, worse with full extension of the knee; no associated effusion or erythema; full, symmetric strength of quadriceps, hip abductors, and hip external rotators; crepitus with knee range of motion; antalgic gait\nNeurologic: alert and oriented; cranial nerves grossly intact; no focal neurologic deficits\"", "answer": "Pain control and rest", "options": {"A": "Pain control and rest", "B": "Physical therapy", "C": "Arthroscopy of the knee", "D": "Synovial fluid analysis", "E": "Intraarticular steroid injection"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 12-month-old boy is brought to the physician by his parents for a 4-week history of fever, malaise, cough, and difficulty breathing. He has had recurrent episodes of gastroenteritis since birth. Cardiopulmonary examination shows subcostal retractions and crackles bilaterally. There is enlargement of the cervical, axillary, and inguinal lymph nodes. An x-ray of the chest shows bilateral consolidations. A sputum culture shows colonies of Burkholderia cepacia. A blood sample is obtained and after the addition of nitroblue tetrazolium to the sample, neutrophils remain colorless. A defect in which of the following is the most likely cause of this patient's condition?", "answer": "NADPH oxidase complex", "options": {"A": "B cell maturation", "B": "Microtubule polymerization", "C": "T cell CD40 ligand", "D": "Actin filament assembly", "E": "NADPH oxidase complex"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-year-old boy is brought to the pediatrician by his mother who is concerned about progressive leg weakness. His mother reports that the patient used to play outside with their neighbors for hours, but for the past few months she has seen him sitting on the sidewalk after 15 minutes because he’s too tired. The patient says his legs are “sleepy.” The patient’s mother has also had to remove the carpets from the house because the patient kept tripping over the edges. The mother reports that the patient is shy but cooperates well with his siblings and other children. He can say his first and last name and just started counting. His mother states he learned to fully walk by 15 months of age. He was hospitalized for bronchiolitis at 12 months of age, which resolved with supportive care. He had an uncomplicated orchiopexy surgery for undescended testes at 7 months of age. He has no other chronic medical conditions and takes no medications. He is up to date on his vaccinations including a flu vaccine 2 weeks ago. The patient’s mother has systemic lupus erythematous and his paternal uncle has dermatomyositis. On physical examination, bilateral calves are large in circumference compared to the thighs. Strength is 3/5 in bilateral quadriceps and 4/5 in bilateral calves. Sensation is intact. Achilles tendon reflexes are 1+ bilaterally. The patient can hop on one leg, but gets tired after 10 jumps. He has a slight waddling gait. Which of the following is the most appropriate test to confirm the diagnosis?", "answer": "Genetic testing", "options": {"A": "Acetylcholine receptor antibody level", "B": "Creatine kinase level", "C": "Genetic testing", "D": "Muscle biopsy", "E": "Nerve conduction study"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old female is brought to the emergency department by her friends. She was supposed to attend her first job interview in a few hours when she started having palpitations. Her past medical history is insignificant, and she currently takes no medications. Her vitals show the following: pulse rate is 90/min, respiratory rate is 28/min, and blood pressure is 136/86 mm Hg. Her ECG is normal. What will be the patient’s approximate alveolar carbon dioxide pressure (PACO2) given her normal respiratory rate is 14/min and PACO2 is 36 mm Hg? Ignore dead space and assume carbon dioxide production is constant.", "answer": "18 mm Hg", "options": {"A": "18 mm Hg", "B": "27 mm Hg", "C": "36 mm Hg", "D": "44 mm Hg", "E": "72 mm Hg"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old man with hypertension comes to the physician because of fatigue and difficulty initiating urination. He wakes up several times a night to urinate. He does not take any medications. His blood pressure is 166/82 mm Hg. Digital rectal examination shows a firm, non-tender, and uniformly enlarged prostate. Which of the following is the most appropriate pharmacotherapy?", "answer": "Terazosin", "options": {"A": "Finasteride", "B": "Phenoxybenzamine", "C": "Tamsulosin", "D": "Terazosin", "E": "α-Methyldopa"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old woman comes to the physician because of numbness of her legs and toes for 3 months. She has also had fatigue and occasional shortness of breath for the past 5 months. She is a painter. Examination shows pale conjunctivae. Sensation to vibration and position is absent over the lower extremities. She has a broad-based gait. The patient sways when she stands with her feet together and closes her eyes. Which of the following laboratory findings is most likely to be seen in this patient?", "answer": "Elevated methylmalonic acid levels\n\"", "options": {"A": "Poliovirus RNA in cerebrospinal fluid", "B": "Basophilic stippling on peripheral smear", "C": "Oligoclonal bands in cerebrospinal fluid", "D": "Positive rapid plasma reagin test", "E": "Elevated methylmalonic acid levels\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 38-year-old woman makes an appointment with her family physician for a routine check-up after being away due to travel for 1 year. She recently had a screening Pap smear, which was negative for malignancy. Her past medical history is significant for a Pap smear 2 years ago that reported a low-grade squamous intraepithelial lesion (LSIL). A subsequent colposcopy diagnosed low-grade cervical intraepithelial neoplasia (CIN2). The patient is surprised by the differences in her diagnostic tests. You explain to her the basis for the difference and reassure her. With this in mind, which of the following HPV serotypes is most likely to be present in the patient?", "answer": "HPV 6", "options": {"A": "HPV 18", "B": "HPV 6", "C": "HPV 31", "D": "HPV 16", "E": "HPV 33"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 19-year-old collegiate football player sustains an injury to his left knee during a game. He was running with the ball when he dodged a defensive player and fell, twisting his left knee. He felt a “pop” as he fell. When he attempts to bear weight on his left knee, it feels unstable, and \"gives way.\" He needs assistance to walk off the field. The pain is localized diffusely over the knee and is non-radiating. His past medical history is notable for asthma. He uses an albuterol inhaler as needed. He does not smoke or drink alcohol. On exam, he has a notable suprapatellar effusion. Range of motion is limited in the extremes of flexion. When the proximal tibia is pulled anteriorly while the knee is flexed and the patient is supine, there is 1.5 centimeter of anterior translation. The contralateral knee translates 0.5 centimeters with a similar force. The injured structure in this patient originates on which of the following bony landmarks?", "answer": "Posteromedial aspect of the lateral femoral condyle", "options": {"A": "Lateral aspect of the lateral femoral condyle", "B": "Lateral aspect of the medial femoral condyle", "C": "Medial aspect of the medial femoral condyle", "D": "Posteromedial aspect of the lateral femoral condyle", "E": "Tibial tubercle"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old woman is brought to the emergency department by her husband due to difficulty speaking and confusion for 1 hour. She was gardening when she suddenly developed these symptoms. She is not able to respond to the questions despite multiple repetitions. She also appears unsteady with her gait and is able to walk with support. The past medical history includes type 2 diabetes mellitus, dyslipidemia, and osteoarthritis. The medicine list includes aspirin, atorvastatin, metformin, and chondroitin sulfate. The vital signs include: blood pressure 174/88 mm Hg, heart rate 154/min and irregular, respiratory rate 12/min, and oxygen saturation 96% on room air. She is awake, but not following commands. The pupils are equal bilaterally and reactive to light. There is mild facial droop on the right side. The forehead wrinkles are preserved. When the soles of her feet are stimulated with a blunt instrument, the right-sided big toe goes upward, while the left-sided big toe goes downward. The ECG shows variable R-R intervals and absent of P waves. What is the next step in the management of this patient?", "answer": "CT scan of the head", "options": {"A": "Amiodarone", "B": "Aspirin", "C": "CT scan of the head", "D": "Echocardiography", "E": "MRI of the head"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old man presents to the physician with a complaint of recurrent chest pain for the last 2 weeks. He mentions that the pain is not present at rest, but when he walks for some distance, he feels pain like a pressure over the retrosternal region. The pain disappears within a few minutes of stopping the physical activity. He is an otherwise healthy man with no known medical disorder. He does not smoke or have any known dependence. There is no family history of ischemic heart disease or vascular disorder. On physical examination, his vital signs, including blood pressure, are normal. The diagnosis of coronary artery disease due to atherosclerosis is made. Which of the following is known to be an infection associated with this patient’s condition?", "answer": "Chlamydophila pneumoniae", "options": {"A": "Chlamydophila pneumoniae", "B": "Coxiella burnetii", "C": "Legionella pneumophilia", "D": "Mycoplasma pneumoniae", "E": "Rickettsia rickettsii"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An investigator is studying cellular repair mechanisms in various tissues. One of the samples being reviewed is from the anterior horn of the spinal cord of a patient who was involved in a snowboard accident. Pathologic examination of the biopsy specimen shows dispersion of the Nissl bodies, swelling of the neuronal body, and a displacement of the nucleus to the periphery in numerous cells. Which of the following is the most likely explanation for the observed findings?", "answer": "Central chromatolysis", "options": {"A": "Neurodegenerative changes", "B": "Wallerian degeneration", "C": "Central chromatolysis", "D": "Reactive astrogliosis", "E": "Neuronal aging"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Fertilization begins when sperm binds to the corona radiata of the egg. Once the sperm enters the cytoplasm, a cortical reaction occurs which prevents other sperm from entering the oocyte. The oocyte then undergoes an important reaction. What is the next reaction that is necessary for fertilization to continue?", "answer": "The second meiotic division", "options": {"A": "Release of a polar body", "B": "Degeneration of the sperm tail", "C": "Acrosome reaction", "D": "The second meiotic division", "E": "Formation of the spindle apparatus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old man presents to his primary care provider with bloody urine. He first noticed the blood 1 week ago. He otherwise feels healthy. His past medical history is significant for type 2 diabetes mellitus for 18 years, for which he takes insulin injections. He has smoked 30–40 cigarettes per day for the past 29 years and drinks alcohol socially. Today his vital signs include: temperature 36.6°C (97.8°F), blood pressure 135/82 mm Hg, and heart rate 105/min. There are no findings on physical examination. Urinalysis shows 15–20 red cells/high power field. Which of the following is the next best test to evaluate this patient’s condition?", "answer": "Contrast-enhanced CT", "options": {"A": "Urine cytology", "B": "Contrast-enhanced CT", "C": "Prostate-specific antigen", "D": "Biopsy", "E": "Urinary markers"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 19-year-old woman comes to the physician because of vaginal discharge for 3 days. She describes the discharge as yellow and mucopurulent with a foul odor. She has also noticed vaginal bleeding after sexual activity. She has not had any itching or irritation. Her last menstrual period was 2 weeks ago. She is sexually active with one male partner, and they use condoms inconsistently. A rapid urine hCG test is negative. Her temperature is 37.3°C (99.1°F), pulse is 88/min, and blood pressure is 108/62 mm Hg. Pelvic examination shows a friable cervix. Speculum examination is unremarkable. A wet mount shows no abnormalities. Which of the following is the most appropriate diagnostic test?", "answer": "Nucleic acid amplification test\n\"", "options": {"A": "Tzanck smear", "B": "Gram stain of cervical swab", "C": "Colposcopy", "D": "Pap smear", "E": "Nucleic acid amplification test\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 35-year-old man with no past medical history presents to his primary care physician with complaints of fatigue. He states that his life has been hectic lately and that everything seems to be falling apart. He is scared that he will lose his job, that his wife will leave him, and that his children will not be able to afford to go to college. His worries are severe enough that they have began to interfere with his daily activities. His wife is also present and states that he has a very secure job and that they are well off financially. She says that he has always worried about something since she met him years ago. What medication would benefit this patient long term?", "answer": "Escitalopram", "options": {"A": "Escitalopram", "B": "Diazepam", "C": "Risperidone", "D": "Lithium", "E": "No treatment recommended"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old man comes to the physician because of blurry vision and fatigue for 2 months. During this period, he has also had occasional bleeding from his gums after brushing his teeth. One month ago, he was diagnosed with deep vein thrombosis after returning from an overseas business meeting. His pulse is 118/min, respirations are 19/min, and blood pressure is 149/91 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. Examination shows bluish discoloration of the lips. The tip of the spleen is palpable 1 cm below the left costal margin. Sensory examination of the hands shows paresthesia. Hemoglobin concentration is 18 g/dL, hematocrit is 65%, leukocytes are 15,000/μL, and platelets are 470,000/μL. His serum erythropoietin concentration is decreased. Activation of which of the following is the most likely underlying cause of this patient's condition?", "answer": "Nonreceptor tyrosine kinase", "options": {"A": "Cytokine receptor", "B": "Transcription factor", "C": "Antiapoptotic molecule", "D": "Nonreceptor tyrosine kinase", "E": "Serine/threonine kinase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman is brought to the emergency department by emergency medical services. She was found trying to hang herself in her kitchen. The patient has a past medical history of drug abuse, alcoholism, anxiety, mania, irritable bowel syndrome, and hypertension. Her current medications include naltrexone, sodium docusate, and clonazepam as needed. Her temperature is 99.5°F (37.5°C), blood pressure is 100/65 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 99% on room air. On physical exam, you note a teary young woman. There are multiple bilateral superficial cuts along her wrists. The patient's cardiac and pulmonary exams are within normal limits. Neurological exam reveals a patient who is alert and oriented. The patient claims that you cannot send her home because if you do she will kill herself. Laboratory values are ordered and return as below.\n\nHemoglobin: 15 g/dL\nHematocrit: 40%\nLeukocyte count: 4,500 cells/mm^3 with normal differential\nPlatelet count: 197,500/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 102 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 90 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.2 mg/dL\nAST: 12 U/L\nALT: 10 U/L\n\nThe patient is transferred to the crisis intervention unit. Which of the following is the best next step in management?", "answer": "Lamotrigine", "options": {"A": "Haloperidol", "B": "Lamotrigine", "C": "Fluoxetine", "D": "Escitalopram", "E": "Diazepam"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-year-old girl is brought to the physician because of a 4-day history of irritation and redness in both eyes. Her symptoms initially started in the left eye and progressed to involve both eyes within 24 hours. She presents with profuse tearing and reports that her eyes are sticky and difficult to open in the morning. She was diagnosed with asthma 2 years ago and has been admitted to the hospital for acute exacerbations 3 times since then. Current medications include inhaled beclomethasone, inhaled albuterol, and montelukast. Her temperature is 38.2 °C (100.8°F). Physical examination reveals a tender left preauricular lymph node. There is chemosis and diffuse erythema of the bulbar conjunctiva bilaterally. Slit lamp examination reveals a follicular reaction in both palpebral conjunctivae and diffuse, fine epithelial keratitis of both corneas. Corneal sensation is normal. Which of the following is the most appropriate next step in management?", "answer": "Supportive therapy", "options": {"A": "Supportive therapy", "B": "Oral cetirizine", "C": "Topical prednisolone acetate", "D": "Topical natamycin", "E": "Topical erythromycin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old woman comes to the physician because of a 4-month history of a painless lump on her neck. Examination shows a hard nodule on the left side of her neck. A fine-needle aspiration biopsy shows well-differentiated cuboidal cells arranged spherically around colloid. She undergoes thyroidectomy. Histopathological examination of the surgical specimen shows invasion of the thyroid capsule and blood vessels. Which of the following cellular events is most likely involved in the pathogenesis of this patient's condition?", "answer": "PAX8-PPAR gamma gene rearrangement", "options": {"A": "TSH receptor gene mutation", "B": "Activation mutation in the BRAF gene", "C": "p53 tumor suppressor gene inactivation", "D": "Mutation in the RET proto-oncogene", "E": "PAX8-PPAR gamma gene rearrangement"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 61-year-old man sustains an intracranial injury to a nerve that also passes through the parotid gland. Which of the following is a possible consequence of this injury?", "answer": "Changes in hearing", "options": {"A": "Loss of taste from posterior 1/3 of tongue", "B": "Loss of general sensation in anterior 2/3 of tongue", "C": "Paralysis of lateral rectus muscle", "D": "Changes in hearing", "E": "Horner's syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 10-month-old boy is admitted to the pediatric intensive care ward because of progressive dyspnea and fever. For the past 2 weeks, he was unsuccessfully treated for an upper respiratory tract infection with ampicillin. He has a history of neonatal sepsis, frequent respiratory tract infections since the age of 3 months, and recurrent otitis media. He was born full-term vaginally to a consanguineous couple from an uncomplicated pregnancy. He received routine immunizations until 6 months of age. The patient’s vital signs are as follows: blood pressure is 70/40 mm Hg, heart rate is 138/min, respiratory rate is 39/min, and temperature is 39.5℃ (103.1 ℉). Physical examination reveals cyanosis, nasal flare, intercostal retractions, and bilaterally decreased breath sounds with crackles heard over the lower lobes on auscultation. The chest X-ray confirms bilateral lower lobe pneumonia. The blood count shows the following findings:\nErythrocytes 4.1 x 106/mm3\nHgb 13 g/dL\nTotal leukocyte count  41,100/mm3\nNeutrophils 74%\nLymphocytes 14%\nEosinophils 2%\nMonocytes 10%\nBasophils 0%\nPlatelet count 210,000/mm3\nThe patient is diagnosed with bilateral community-acquired lower lobe pneumonia and prescribed antibiotics. An immunological workup is performed to assess the patient’s immunity:\nMeasurement Result Normal range\nAntibodies\nTotal serum IgG 22.0 mg/dL  231–1,411 mg/dL \nSerum IgA 59.3 mg/dL 0–83 mg/dL\nSerum IgM 111.9 mg/dL 0–145 mg/dL\nLymphocyte flow cytometry\nCD3+ cells 2.2% 60–85%\nCD19+ cells 95.1% 8–20%\nCD16/CD56+ cells  0.1% 3–30%\nWhich of the following procedures is the option of choice for the further management of this patient?", "answer": "Bone marrow transplantation", "options": {"A": "Periodical prophylactic antibiotic administration", "B": "Periodical intravenous immune globulin administration", "C": "Thymectomy", "D": "Bone marrow transplantation", "E": "Chemotherapy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old man arrives to the clinic complaining of progressive weakness. He explains that for 3 months he has had difficulty climbing the stairs, which has now progressed to difficulty getting out of a chair. He denies diplopia, dysphagia, dyspnea, muscle aches, or joint pains. He denies weight loss, weight gain, change in appetite, or heat or cold intolerance. He reports intermittent low-grade fevers. He has a medical history significant for hypertension and hyperlipidemia. He has taken simvastatin and losartan daily for the past 6 years. His temperature is 99.0°F (37.2°C), blood pressure is 135/82 mmHg, and pulse is 76/min. Cardiopulmonary examination is normal. The abdomen is soft, non-tender, non-distended, and without hepatosplenomegaly. Muscle strength is 3/5 in the hip flexors and 4/5 in the deltoids, biceps, triceps, patellar, and Achilles tendon reflexes are 2+ and symmetric. Sensation to pain, light touch, and vibration are intact. Gait is cautious, but grossly normal. There is mild muscle tenderness of his thighs and upper extremities. There is no joint swelling or erythema and no skin rashes. A complete metabolic panel is within normal limits. Additional lab work is obtained as shown below:\n\nSerum:\nNa+: 141 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 23 mEq/L\nUrea nitrogen: 18 mg/dL\nGlucose: 128 mg/dL\nCreatinine: 1.0 mg/dL\nAlkaline phosphatase: 69 U/L\nAspartate aminotransferase (AST): 302 U/L\nAlanine aminotransferase (ALT): 210 U/L\nTSH: 6.9 uU/mL\nThyroxine (T4): 5.8 ug/dL\nCreatine kinase: 4300 U/L\nC-reactive protein: 11.9 mg/L\nErythrocyte sedimentation rate: 37 mm/h\n\nWhich of the following is the most accurate diagnostic test?", "answer": "Muscle biopsy", "options": {"A": "Autoantibodies", "B": "Electromyography", "C": "Fine needle aspiration", "D": "Muscle biopsy", "E": "Statin cessation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old man presents with an episode of rectal bleeding. He is concerned because his mother died of colorectal cancer at 50 years of age. He has no further information about his family history. Physical examination and digital rectal examination are normal. He undergoes a colonoscopy and is found to have innumerable adenomas in the left side of the colon ranging in size from 4–15 mm. Which of the following is the most likely underlying mechanism of this patient illness?", "answer": "Mutations of the APC gene", "options": {"A": "Mutation in DNA mismatch repair genes", "B": "Alterations in STK11 gene", "C": "Mutations of the APC gene", "D": "Inactivation of RB1 gene", "E": "Inactivation of BRCA1 and BRCA2 genes"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old man presents to his physician with a history of excessive thirst and excessive urination over the last 3 weeks. He mentions that he has to wake up multiple times at night to urinate. A detailed history reveals that he has a known case of bipolar mood disorder and has been taking lithium carbonate for 5 years. His urinary specific gravity is 1.003, and his urinary osmolality is 150 mOsm/kg H2O. Which of the following Darrow-Yannet diagrams best describes the status of volumes and osmolality of this man’s body fluids?", "answer": "Image 2", "options": {"A": "Image 1", "B": "Image 2", "C": "Image 3", "D": "Image 4", "E": "IMage 5"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 8-year-old African American girl is brought to the clinic by her mother for her regular blood exchange. They come in every 2–3 months for the procedure. The child is in good health with no symptoms. Her last trip to the emergency department was 6 months ago due to bone pain. She was treated with morphine and oxygen and a blood transfusion. She takes hydroxyurea and a multivitamin with iron every day. She has an uncle that also has to get blood exchanges. Today, her heart rate is 90/min, respiratory rate is 17/min, blood pressure is 110/65 mm Hg, and temperature is 37.0°C (98.6°F). She calmly waits for the machine to be set up and catheters inserted into both of her arms. She watches a movie as her blood is slowly replaced with 6 L of red blood cells. Based on this history, which of the following mechanisms most likely explains this patient’s condition?", "answer": "Amino acid substitution", "options": {"A": "Amino acid deletion", "B": "Amino acid substitution", "C": "Enzyme deficiency", "D": "Trinucleotide repeat", "E": "Nonsense mutation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 75-year-old woman presents to the emergency department because of a brief loss of consciousness, slurred speech, and facial numbness. Family members report that she complained about feeling chest pain and shortness of breath while on her morning walk. Medical history is noncontributory. Physical examination shows decreased pupil reactivity to light and hemiplegic gait. Her pulse is 120/min, respirations are 26/min, temperature is 36.7°C (98.0°F), and blood pressure is 160/80 mm Hg. On heart auscultation, S1 is loud, widely split, and there is a diastolic murmur. Transthoracic echocardiography in a 4-chamber apical view revealed a large oval-shaped and sessile left atrial mass. Which of the following is the most likely complication of this patient's condition?", "answer": "Mitral valve obstruction", "options": {"A": "Atrial fibrillation", "B": "Atrioventricular block", "C": "Congestive heart failure", "D": "Mitral valve obstruction", "E": "Pericarditis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old man presents to the office with complaints of fatigue and difficulty breathing for the past few weeks. He also complains of early morning stiffness of his metatarsophalangeal and metacarpophalangeal joints on both sides that lasts for 2 hours. He feels better only after a warm water tub bath every day in the morning. He denies noticing any kind of rash on his body. He has been working in the shipbuilding industry for 20 years. He loves skin tanning and hunting in summer. He smokes 2 packs of cigarettes every day and has been doing so for the past 15 years. His pulmonary function test shows reduced forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio with a reduction of both FEV1 and FEV1 and decreased diffusing capacity of the lungs for carbon monoxide (DLCO). His chest X-ray shows multiple nodules with calcification. Which of the following antibodies will most likely be present in this patient that is very specific to the condition he has?", "answer": "Anti-CCP", "options": {"A": "Anti-CCP", "B": "Anti-Scl 70", "C": "Anti-Ro", "D": "Anti-ds-DNA", "E": "Anti-Jo1"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 29-year-old man presents to clinic with a complaint of fatigue that has developed over the past 6 months. Upon questioning, he endorses abdominal pain, non-bloody diarrhea, and decreased appetite over the past year. He denies recent travel outside of the country or eating uncooked meats. On exam, his temperature is 99.0°F (37.2°C), blood pressure is 126/78 mmHg, pulse is 93/min, and respirations are 12/min. Notably, the abdominal exam is unremarkable aside from some tenderness to palpation near the umbilicus. His colonoscopy demonstrates perianal inflammation with a normal rectum, and biopsies of suspicious lesions in the transverse colon reveal transmural inflammation. Which one of the following is most strongly associated with the patient’s condition?", "answer": "Kidney stones", "options": {"A": "Colorectal cancer", "B": "Endocarditis", "C": "Hemolytic anemia", "D": "Kidney stones", "E": "Positive serum transglutaminase antibodies"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old male presents to your clinic with shortness of breath and lower extremity edema. He was born in Southeast Asia and emigrated to America ten years prior. Examination demonstrates 2+ pitting edema to the level of his knees, ascites, and bibasilar crackles, as well as an opening snap followed by a mid-to-late diastolic murmur. The patient undergoes a right heart catheterization that demonstrates a pulmonary capillary wedge pressure (PCWP) of 24 mmHg. The patient is most likely to have which of the following?", "answer": "Normal or decreased left ventricular end diastolic pressure (LVEDP)", "options": {"A": "Increased pulmonary vascular compliance", "B": "Decreased pulmonary artery systolic pressure (PASP)", "C": "Increased left ventricular end diastolic pressure (LVEDP)", "D": "Normal or decreased left ventricular end diastolic pressure (LVEDP)", "E": "Decreased transmitral gradient"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old man comes to the physician for a follow-up examination after he was diagnosed with mantle cell lymphoma. The physician recommends a chemotherapeutic regimen containing bortezomib. Which of the following best describes the effect of this drug?", "answer": "Accumulation of ubiquitinated proteins", "options": {"A": "Stabilization of tubulin polymers", "B": "Accumulation of ubiquitinated proteins", "C": "Crosslinking of purine bases", "D": "Preventing the relaxation of DNA supercoils", "E": "Inhibition of tyrosine kinase receptors"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 57-year-old man presents for his yearly wellness visit. He says he has been feeling well and has no complaints. No significant past medical history or current medications. The patient reports a 35-pack-year smoking history but says he quit 5 years ago. His family history is significant for lung cancer in his father who died at age 67. His vital signs include: temperature 36.8°C (98.2°F), pulse 95/min, respiratory rate 16/min, blood pressure 100/75 mm Hg. Physical examination is unremarkable. Laboratory findings are significant for the following:\nSerum potassium 3.9 mEq/L\nSerum sodium 140 mEq/L\nSerum chloride 103 mEq/L\nSerum calcium 2.5 mmol/L\nBUN 15 mg/dL\nCreatinine 0.8 mg/dL\nGlucose 95 mg/dL\nMagnesium 1.7 mEq/L\nPhosphate 1.1 mmol/L\nHemoglobin 14 g/dL\nBicarbonate (HCO3-) 25 mEq/L\nBilirubin, total 0.9 mg/dL\nBilirubin, indirect 0.4 mg/dL\nAST 10 U/L  \nALT 19 U/L  \nAlkaline phosphatase 40 U/L\nAlbumin 3.6 g/dL\nWhich of the following preventative screening tests is recommended for this patient at this time?", "answer": "Low-dose CT scan (LDCT) of the chest", "options": {"A": "Chest X-ray", "B": "Abdominal ultrasound", "C": "ECG", "D": "Low-dose CT scan (LDCT) of the chest", "E": "No screening indicated"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 49-year-old woman presents to her physician with a fever accompanied by chills and burning micturition since the past 5 days. She is an otherwise healthy woman with no significant past medical history and has an active sexual life. On physical examination, her temperature is 39.4°C (103.0°F), pulse rate is 90/min, blood pressure is 122/80 mm Hg, and respiratory rate is 14/min. Examination of the abdomen and genitourinary region do not reveal any specific positive findings. The physician orders a urinalysis of fresh unspun urine for this patient which shows 25 WBCs/mL of urine. The physician prescribes an empirical antibiotic and other medications for symptom relief. He also orders a bacteriological culture of her urine. After 48 hours of treatment, the woman returns to the physician to report that her symptoms have not improved. The bacteriological culture report indicates the growth of gram-negative bacilli which are lactose-negative and indole-negative, which produce a substance that hydrolyzes urea to produce ammonia. Which of the following bacteria is the most likely cause of infection in the woman?", "answer": "Proteus mirabilis", "options": {"A": "Citrobacter freundii", "B": "Escherichia coli", "C": "Enterobacter cloacae", "D": "Klebsiella pneumoniae", "E": "Proteus mirabilis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old man presents to his primary care physician with progressively worsening hearing loss. He states that his trouble with hearing began approximately 7-8 years ago. He is able to hear when someone is speaking to him; however, he has difficulty with understanding what is being said, especially when there is background noise. In addition to his current symptoms, he reports a steady ringing in both ears, and at times experiences dizziness. Medical history is significant for three prior episodes of acute otitis media. Family history is notable for his father being diagnosed with cholesteatoma. His temperature is 98.6°F (37°C), blood pressure is 138/88 mmHg, pulse is 14/min, and respirations are 13/min. On physical exam, when a tuning fork is placed in the middle of the patient's forehead, sound is appreciated equally on both ears. When a tuning fork is placed by the external auditory canal and subsequently on the mastoid process, air conduction is greater than bone conduction. Which of the following is most likely the cause of this patient's symptoms?", "answer": "Cochlear hair cell degeneration", "options": {"A": "Accumulation of desquamated keratin debri", "B": "Eustachian tube obstruction secondary to nasopharyngeal inflammatory edema", "C": "Stapedial abnormal bone growth", "D": "Cochlear hair cell degeneration", "E": "Endolymphatic hydrops"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying the molecular structure of various proteinogenic L-amino acids. The structure of one of the amino acids being studied is shown. The derivative of this amino acid is most likely to cause which of the following effects in the human body?", "answer": "Peripheral vasodilation", "options": {"A": "Ketotic acidosis", "B": "Skin pigmentation", "C": "Pupillary dilation", "D": "Peripheral vasodilation", "E": "Respiratory depression"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old man presents to his primary care physician with a 4-week history of back pain. He says that the pain does not appear to be associated with activity and is somewhat relieved by taking an NSAID. Furthermore, he says that he has had increasing difficulty trying to urinate. His past medical history is significant for kidney stones and a 30-pack-year smoking history. Radiographs reveal osteoblastic lesions in the spine. Which of the following drugs would most likely be effective in treating this patient's disease?", "answer": "Continuous leuprolide", "options": {"A": "Continuous leuprolide", "B": "Imatinib", "C": "Pulsatile leuprolide", "D": "Rituximab", "E": "Tamsulosin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 29-year-old woman presents with skin lesions on her elbows and forearms. She notes that they first started appearing 2 months ago and have not improved. She describes the lesions as painless and rarely itchy. She denies any similar symptoms in the past, and has no other significant past medical history. Review of systems is significant for recent joint pain, conjunctivitis, and corneal dryness. The patient is afebrile and vital signs are within normal limits. Non-tender, raised, inflamed, white-silver maculopapular lesions are present. Which of the following are the most likely histopathologic findings in this patient's skin biopsy?", "answer": "Basal cell hyperplasia, proliferation of subepidermal vasculature, and keratinization", "options": {"A": "Intracellular edema with detachment at basal level", "B": "Subepidermal blister (detachment at suprabasal level)", "C": "Cytoplasmic vacuolation", "D": "Basal cell hyperplasia, proliferation of subepidermal vasculature, and keratinization", "E": "Nuclear atypia, cellular pleomorphism, and a disorganized structure of cells from basal to apical layers of the tissue"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Two days after delivery, a newborn develops a red, irritated eye with yellow discharge. She was born at 39 weeks' gestation to a 28-year-old woman, gravida 1, para 1. Pregnancy and delivery were uncomplicated. The mother had not seen her gynecologist since her first prenatal visit. The newborn's temperature is 37.2°C (99.0°F), pulse is 140/min, respirations are 42/min, and blood pressure is 73/53 mm Hg. Ophthalmic examination shows eyelid edema, conjunctival injection, and copious yellow mucopurulent discharge from the right eye. There is no corneal ulceration or evidence of keratitis. Funduscopic examination is normal. The diagnosis is confirmed and appropriate treatment is administered. Which of the following is most likely to have prevented this patient's condition?", "answer": "Topical erythromycin administered to the infant", "options": {"A": "Oral erythromycin administered to the infant", "B": "IV ceftriaxone administered to the infant", "C": "Topical erythromycin administered to the infant", "D": "Oral doxycycline administered to the mother", "E": "Oral amoxicillin administered to the mother"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 16-year-old boy is brought to the emergency department after losing consciousness. He had no preceding chest pain or palpitations. His father has cataracts and had frontal balding in his twenties but has no history of cardiac disease. His paternal grandfather also had early-onset balding. His pulse is 43/min. Physical examination shows frontal hair loss, temporal muscle wasting, and testicular atrophy. Neurologic examination shows bilateral foot drop and weakness of the intrinsic hand muscles. An ECG shows bradycardia with third-degree atrioventricular block. The severity of this patient's symptoms compared to that of his father is most likely due to which of the following genetic properties?", "answer": "Anticipation", "options": {"A": "Pleiotropy", "B": "Loss of heterozygosity", "C": "Codominance", "D": "Penetrance", "E": "Anticipation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old primigravida at 35 weeks gestation seeks evaluation at the emergency department for swelling and redness of the left calf, which started 2 hours ago. She reports that the pain has worsened since the onset. The patient denies a history of insect bites or trauma. She has never experienced something like this in the past. Her pregnancy has been uneventful so far. She does not use alcohol, tobacco, or any illicit drugs. She does not take any medications other than prenatal vitamins. Her temperature is 36.8℃ (98.2℉), the blood pressure is 105/60 mm Hg, the pulse is 110/min, and the respirations are 15/min. The left calf is edematous with the presence of erythema. The skin feels warm and pain is elicited with passive dorsiflexion of the foot. The femoral, popliteal, and pedal pulses are palpable bilaterally. An abdominal examination reveals a fundal height consistent with the gestational age. The lungs are clear to auscultation bilaterally. The patient is admitted to the hospital and appropriate treatment is initiated. Which of the following hormones is most likely implicated in the development of this patient’s condition?", "answer": "Estriol", "options": {"A": "Estriol", "B": "Progesterone", "C": "Human chorionic gonadotropin", "D": "Human placental lactogen", "E": "Prolactin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old nurse at 8 weeks of gestation presents to the physician with low-grade fever and body ache for the past 2 days. She also complains of a fine pink and itchy rash that appeared 2 nights ago. The rash 1st appeared on her face and spread to her neck. Past medical history is noncontributory. She takes prenatal vitamins with folate every day. She has had many sick contacts while working in the hospital. Additionally, her daughter has had several colds over the last few months. On examination, the temperature is 38.3°C (100.9°F), she has a fine macular rash on her face and neck with focal macules on her chest. Palpation of the neck reveals lymphadenopathy in the posterior auricular nodes. What is the most appropriate next step in the management of this patient?", "answer": "Test for rubella antibodies in her blood", "options": {"A": "Administer anti-rubella antibodies", "B": "Admit the patient and place her in isolation", "C": "Administer rubella vaccine", "D": "Test for rubella antibodies in her blood", "E": "Termination of pregnancy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man with a history of fatigue and exertional dyspnea presents to the urgent care clinic following an acute upper respiratory illness. On physical examination, his pulses are bounding, his complexion is very pale, and scleral icterus is apparent. The spleen is moderately enlarged. Oxygen saturation is 79% at rest, with a new oxygen requirement of 9 L by a non-rebreather mask. Laboratory analysis results show a hemoglobin level of 6.8 g/dL. Of the following options, which hypersensitivity reaction does this condition represent?", "answer": "Type II–cytotoxic hypersensitivity reaction", "options": {"A": "Type I–anaphylactic hypersensitivity reaction", "B": "Type II–cytotoxic hypersensitivity reaction", "C": "Type III–immune complex-mediated hypersensitivity reaction", "D": "Type IV–cell-mediated (delayed) hypersensitivity reaction", "E": "Type II and II–mixed cytotoxic and immune complex hypersensitivity reaction"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old HIV-positive male with a history of intravenous drug abuse presents to the emergency room complaining of arm swelling. He reports that he developed progressively worsening swelling and tenderness over the right antecubital fossa three days prior. He recently returned from a trip to Nicaragua. His past medical history is notable for an anaphylactoid reaction to vancomycin. His temperature is 101.4°F (38.6°C), blood pressure is 140/70 mmHg, pulse is 110/min, and respirations are 20/min. Physical examination reveals an erythematous, fluctuant, and tender mass overlying the right antecubital fossa. Multiple injection marks are noted across both upper extremities. He undergoes incision and drainage and is started on an antibiotic that targets the 50S ribosome. He is discharged with plans to follow up in one week. However, five days later he presents to the same emergency room complaining of abdominal cramps and watery diarrhea. Which of the following classes of pathogens is most likely responsible for this patient’s current symptoms?", "answer": "Gram-positive bacillus", "options": {"A": "Gram-negative curved bacillus", "B": "Gram-negative bacillus", "C": "Anaerobic flagellated protozoan", "D": "Gram-positive coccus", "E": "Gram-positive bacillus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 69-year-old male presents to the emergency department for slurred speech and an inability to use his right arm which occurred while he was eating dinner. The patient arrived at the emergency department within one hour. A CT scan was performed of the head and did not reveal any signs of hemorrhage. The patient is given thrombolytics and is then managed on the neurology floor. Three days later, the patient is recovering and is stable. He seems depressed but is doing well with his symptoms gradually improving as compared to his initial presentation. The patient complains of neck pain that has worsened slowly over the past few days for which he is being given ibuprofen. Laboratory values are ordered and return as indicated below:\n\nSerum:\nNa+: 130 mEq/L\nK+: 3.7 mEq/L\nCl-: 100 mEq/L\nHCO3-: 24 mEq/L\nUrea nitrogen: 7 mg/dL\nGlucose: 70 mg/dL\nCreatinine: 0.9 mg/dL\nCa2+: 9.7 mg/dL\n\nUrine:\nAppearance: dark\nGlucose: negative\nWBC: 0/hpf\nBacterial: none\nNa+: 320 mEq/L/24 hours\n\nHis temperature is 99.5°F (37.5°C), pulse is 95/min, blood pressure is 129/70 mmHg, respirations are 10/min, and oxygen saturation is 98% on room air. Which of the following is the best next step in management?", "answer": "Fluid restriction", "options": {"A": "Fluid restriction", "B": "Oral salt tablets", "C": "Demeclocycline", "D": "Conivaptan", "E": "Continue conservative management"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 70-year-old man with a 2 year history of Alzheimer disease presents is brought in from his nursing facility with altered mental status and recurrent falls during the past few days. Current medications include donepezil and galantamine. His vital signs are as follows: temperature 36.0°C (96.8°F), blood pressure 90/60 mm Hg, heart rate 102/min, respiratory rate 22/min. Physical examination reveals several lacerations on his head and extremities. He is oriented only to the person. Urine and blood cultures are positive for E. coli. The patient is admitted and initial treatment with IV fluids, antibiotics, and subcutaneous prophylactic heparin. On the second day of hospitalization, diffuse bleeding from venipuncture sites and wounds is observed. His blood test results show thrombocytopenia, prolonged PT and PTT, and a positive D-dimer. Which of the following is the most appropriate next step in the management of this patient’s condition?", "answer": "Cryoprecipitate, FFP and low dose SC heparin", "options": {"A": "Immediately cease heparin therapy and prescribe an alternative anticoagulant", "B": "Start prednisone therapy", "C": "Cryoprecipitate, FFP and low dose SC heparin", "D": "Urgent plasma exchange", "E": "Splenectomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 59-year-old woman is brought to the emergency department for the confusion. She was in her usual state of health until about 2 hours ago when she was found trying to cook a frozen pizza in her medicine cabinet. She also complained to her husband that she had a terrible headache. Her past medical history is notable for hypertension, which has been difficult to control on multiple medications. Her temperature is 37.1°C (98.8°F), the pulse is 75/min, and the blood pressure is 202/128 mm Hg. On physical exam, she is alert and oriented only to self. The physical exam is otherwise unremarkable and the neurologic exam shows no focal neurological deficits. Noncontrast CT head imaging is unremarkable; a T2-weighted image from the patient’s MRI brain scan is shown. Which of the following is the next best step in management for this patient?", "answer": "IV nicardipine", "options": {"A": "IV lorazepam", "B": "IV nicardipine", "C": "IV phenytoin", "D": "IV tissue plasminogen activator (tPA)", "E": "IV vancomycin, ceftriaxone, and ampicillin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old man is brought to the emergency department by his father because he is having bizarre thoughts. The patient says that he is being haunted by aliens from outer space. The father is worried as his son has had these symptoms for the past 7 months and lately, it seems to be getting worse. He has become more self-obsessed and does not seem to have any interest in his favorite activities. He has no plans to harm himself or others but spends a lot of time and energy building ‘defenses’ in and around his room as he is absolutely sure that aliens will come to get him soon. His blood pressure is 121/79 mm Hg, pulse 86/min, respiratory rate 15/min, temperature 36.8°C (98.2°F). Which of the following is correct regarding the patient’s symptoms?", "answer": "He has a fixed false belief.", "options": {"A": "It would benefit from psychosurgery.", "B": "He has a fixed false belief.", "C": "It is a negative symptom.", "D": "It falls under the disorganized thinking domain.", "E": "It is amenable to cognitive behavioral therapy."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A family doctor in a rural area is treating a patient for dyspepsia. The patient had chronic heartburn and abdominal pain for the last 2 months and peptic ulcer disease due to a suspected H. pylori infection. For reasons relating to affordability and accessibility, the doctor decides to perform a diagnostic test in the office that is less invasive and more convenient. Which of the following is the most likely test used?", "answer": "Serology (ELISA testing)", "options": {"A": "Detection of the breakdown products of urea in biopsy", "B": "Steiner's stain", "C": "Stool antigen test", "D": "Culture of organisms from gastric specimen", "E": "Serology (ELISA testing)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old man comes to the physician with difficulty swallowing for several weeks. Examination of the oropharynx shows lesions on palate and tongue that can be easily scraped off. An image of the lesions is shown. Which of the following is a risk factor for this patient's findings?", "answer": "Decline in CD4+ T-cells", "options": {"A": "Decline in CD4+ T-cells", "B": "Inhalation of salbutamol", "C": "Missed childhood vaccination", "D": "Chronic nicotine abuse", "E": "Epstein-Barr virus infection"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old boy presents with difficult left eye-opening in the morning, eye discharge, and irritation. These symptoms developed gradually over the past week. He attends a primary school where recently an outbreak of tonsillitis took place. He had otitis media 2 weeks ago treated with ampicillin. At the presentation, the patient’s vital signs are within normal limits. Eye examination reveals bulbar conjunctival injection, mild eyelid edema, and a moderate mucopurulent discharge with crusts on the lower eyelid. There is no corneal or eyelid ulceration. No lymphadenopathy is noted. Which of the following investigations should be performed to establish a diagnosis before the treatment?", "answer": "No investigations are required in this case", "options": {"A": "Bacterial culture of the discharge", "B": "No investigations are required in this case", "C": "Rapid viral test", "D": "Scrapings with Gram staining", "E": "Polymerase chain reaction"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32 year-old African American man with a past medical history of sickle cell anemia presents to his primary care physician for a routine check-up. He has no complaints. His physician notes that he likely has an increased susceptibility to infections with certain organisms. Which of the following patient groups has a similar pattern of increased susceptibility?", "answer": "C3 complement deficiency", "options": {"A": "C5-9 complement deficiency", "B": "T-cell deficiency", "C": "C3 complement deficiency", "D": "Hemophilia A", "E": "Hemophilia B"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3175-g (7-lb) male newborn is delivered at 39 weeks' gestation to a 29-year-old primigravid woman following a spontaneous vaginal delivery. Apgar scores are 8 and 9 at 1 and 5 minutes, respectively. Cardiac examination in the delivery room shows a continuous machine-like murmur. An echocardiogram shows a structure with blood flow between the pulmonary artery and the aorta. This structure is most likely a derivate of which of the following?", "answer": "6th aortic arch", "options": {"A": "4th aortic arch", "B": "2nd aortic arch", "C": "6th aortic arch", "D": "1st aortic arch", "E": "3rd aortic arch"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year-old man with a past medical history of type I diabetes mellitus presents to the emergency department with altered mental status. The patient was noted as becoming more lethargic and confused over the past day, prompting his roommates to bring him in. His temperature is 99.0°F (37.2°C), blood pressure is 107/68 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 144 mEq/L\nCl-: 100 mEq/L\nK+: 6.3 mEq/L\nHCO3-: 16 mEq/L\nBUN: 20 mg/dL\nGlucose: 599 mg/dL\nCreatinine: 1.4 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the appropriate endpoint of treatment for this patient?", "answer": "Normal anion gap", "options": {"A": "Clinically asymptomatic", "B": "Normal anion gap", "C": "Normal glucose", "D": "Normal potassium", "E": "Vitals stable"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "The drug cilostazol is known for its ability to relax vascular smooth muscle and therefore cause vasodilation through its inhibition of phosphodiesterase 3. Given this mechanism of action, what other effect would be expected?", "answer": "Positive inotropy", "options": {"A": "Increased left ventricular end-diastolic volume", "B": "Positive inotropy", "C": "Negative chronotropy", "D": "Angioedema", "E": "Antiarrhythmic action"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 43-year-old woman presents to her primary care provider with shortness of breath. She reports a 4-month history of progressively worsening difficulty breathing with associated occasional chest pain. She is a long-distance runner but has had trouble running recently due to her breathing difficulties. Her past medical history is notable for well-controlled hypertension for which she takes hydrochlorothiazide. She had a tibial osteosarcoma lesion with pulmonary metastases as a child and successfully underwent chemotherapy and surgical resection. She has a 10 pack-year smoking history but quit 15 years ago. She drinks a glass of wine 3 times per week. Her temperature is 98.6°F (37°C), blood pressure is 140/85 mmHg, pulse is 82/min, and respirations are 18/min. On exam, she has increased work of breathing with a normal S1 and loud P2. An echocardiogram in this patient would most likely reveal which of the following?", "answer": "Right ventricular hypertrophy with a dilated pulmonary artery", "options": {"A": "Biventricular dilatation with a decreased ejection fraction", "B": "Left atrial dilatation with mitral valve stenosis", "C": "Left ventricular dilatation with an incompetent aortic valve", "D": "Left ventricular hypertrophy with a bicuspid aortic valve", "E": "Right ventricular hypertrophy with a dilated pulmonary artery"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old man presents to the physician with nausea, vomiting, constipation, and abdominal pain for the past 24 hours. He has also developed difficulty in swallowing and blurring of vision. He also complains of significant dryness of his mouth and throat. When asked about his diet, he reports that he has been saving money by eating dented and old canned goods. On physical examination, his vital signs are stable. His neurologic examination reveals bilateral fixed dilated pupils, weakness of extraocular muscles, and weak gag reflex, while sensations and gait are normal. Laboratory evaluation of his stool isolates a toxin produced by gram-positive, anaerobic, spore-forming bacilli. Which of the following mechanisms best explains the action of the toxin?", "answer": "Blockade of release of acetylcholine at neuromuscular junctions", "options": {"A": "Blockade of voltage-gated fast sodium channels in motor neurons", "B": "Blockade of release of acetylcholine at neuromuscular junctions", "C": "Inactivation of acetylcholinesterase at neuromuscular junctions", "D": "Competitive antagonism of acetylcholine at postsynaptic receptors", "E": "Prolonged depolarization of NM receptors"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old woman comes to the physician because of involuntary rhythmic shaking of both hands for several months. More recently, she also noticed involuntary head nodding movements. The shaking seems to improve after having one or two glasses of wine. Her father had similar symptoms starting at the age of 60. Neurologic examination shows a symmetric hand tremor that worsens with voluntary movement of the respective extremity. The most appropriate pharmacotherapy for this patient's symptoms is also recommended for the treatment of which of the following conditions?", "answer": "Hyperthyroidism", "options": {"A": "Motion sickness", "B": "Restless legs syndrome", "C": "Sleepwalking", "D": "Hyperthyroidism", "E": "Malignant hyperthermia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old woman is brought to the emergency department 4 hours after the sudden onset of shortness of breath and dizziness. Her blood pressure is 88/56 mm Hg. Examination shows crackles at both lung bases and an S3 gallop. The extremities are cold to the touch. Serum studies show a urea nitrogen concentration of 15 mg/dL, a creatinine concentration of 1.0 mg/dL, and a lactic acid concentration of 6.4 mmol/L (N < 2). Arterial blood gas analysis on room air shows:\npH 7.27\npCO2 36 mm Hg\nHCO3- 15 mEq/L\nAn ECG shows ST-segment elevation in the precordial leads. Which of the following is the most likely explanation for this patient's laboratory changes?\"", "answer": "Accumulation of NADH", "options": {"A": "Catecholamine stimulation of glycolysis", "B": "Decreased reabsorption of HCO3-", "C": "Increased activity of HMG-CoA lyase", "D": "Defective mitochondrial oxygen utilization", "E": "Accumulation of NADH"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 24-year-old woman comes to the physician because of fever, headache, myalgia, photophobia, and a nonproductive cough for 2 days. Three weeks ago, she received a parrot as a birthday present. Her temperature is 38.5°C (101.3°F). Pulmonary examination shows crackles at both lung bases. Her leukocyte count is 8,000/mm3. An x-ray of the chest shows diffuse patchy infiltrates that are most prominent in the lower lobes. Which of the following is the most likely causal organism?", "answer": "Chlamydophila psittaci", "options": {"A": "Chlamydophila psittaci", "B": "Cryptococcus neoformans", "C": "Leptospira interrogans", "D": "Babesia microti", "E": "Francisella tularensis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 71-year-old woman presents to the emergency department with a headache for the past 30 minutes. She says that this is the worst headache of her life and that it came on suddenly after she hit her head. She says that she has also been experiencing visual problems with double vision when she looks to the left or the right. Visual examination reveals that her right eye cannot move right past the midline and her left eye cannot move left past the midline. Which of the following is most likely responsible for this patient's visual defects?", "answer": "Central herniation", "options": {"A": "Bilateral uncal herniation", "B": "Central herniation", "C": "Subfalcine herniation", "D": "Tonsillar herniation", "E": "Unilateral uncal herniation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old man comes to the physician because of intermittent throbbing headaches over the past year. The headaches are worse when he wakes up and are not accompanied by other symptoms. The patient also reports trouble concentrating on daily tasks at work. His wife has been complaining lately about his snoring during sleep, which he attributes to his chronic sinusitis. He has a history of hypertension and an allergy to dust mites. He has smoked a pack of cigarettes daily for 14 years. His pulse is 72/min and blood pressure is 150/95 mm Hg. He is 178 cm (5 ft 10 in) tall and weighs 120 kg (265 lb); BMI is 37.9 kg/m2. Neurological and cutaneous examination shows no abnormalities. Which of the following is the most likely cause of this patient's hypertension?", "answer": "Nocturnal upper airway obstruction", "options": {"A": "Low circulating free thyroxine levels", "B": "Nocturnal upper airway obstruction", "C": "Hypophyseal neoplasm", "D": "Hypersecretion of aldosterone", "E": "Low synaptic serotonin levels"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 75-year-old man presents to the emergency department for abdominal pain. The patient states the pain started this morning and has been worsening steadily. He decided to come to the emergency department when he began vomiting. The patient has a past medical history of obesity, diabetes, alcohol abuse, and hypertension. His current medications include captopril, insulin, metformin, sodium docusate, and ibuprofen. His temperature is 104.0°F (40°C), blood pressure is 160/97 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. Abdominal exam reveals left lower quadrant tenderness. Cardiac exam reveals a crescendo systolic murmur heard best by the right upper sternal border. Lab values are ordered and return as below.\n\nHemoglobin: 15 g/dL\nHematocrit: 42%\nLeukocyte count: 19,500 cells/mm^3 with normal differential\nPlatelet count: 226,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 101 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 24 mEq/L\nBUN: 22 mg/dL\nGlucose: 144 mg/dL\nCreatinine: 1.2 mg/dL\nCa2+: 9.8 mg/dL\n\nWhich of the following is the most accurate test for this patient's condition?", "answer": "CT scan", "options": {"A": "Amylase and lipase levels", "B": "Barium enema", "C": "Colonoscopy", "D": "CT scan", "E": "Sigmoidoscopy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old man is brought to the emergency department by his brother because of a 3-hour history of lethargy and confusion. The brother says that 2 days ago, the patient ate several large-capped mushrooms he had foraged in the woods. After eating the mushrooms, he developed severe, bloody diarrhea that has since resolved. His pulse is 140/min, respirations are 26/min, and blood pressure is 98/62 mm Hg. Examination shows dry mucous membranes and tenderness to deep palpation in the right upper quadrant. Serum studies show a serum AST concentration of 2335 U/L and ALT concentration of 2294 U/L. Inhibition of which of the following processes is the most likely cause of this patient's condition?", "answer": "Messenger RNA synthesis", "options": {"A": "Messenger RNA synthesis", "B": "ATP production", "C": "Microtubule polymerization", "D": "Parasympathetic activation", "E": "Cell depolarization"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 76-year-old man is brought to the hospital after having a stroke. Head CT is done in the emergency department and shows intracranial hemorrhage. Upon arrival to the ED he is verbally non-responsive and withdraws only to pain. He does not open his eyes. He is transferred to the medical ICU for further management and intubated for airway protection. During his second day in the ICU, his blood pressure is measured as 91/54 mmHg and pulse is 120/min. He is given fluids and antibiotics, but he progresses to renal failure and his mental status deteriorates. The physicians in the ICU ask the patient’s family what his wishes are for end-of-life care. His wife tells the team that she is durable power of attorney for the patient and provides appropriate documentation. She mentions that he did not have a living will, but she believes that he would want care withdrawn in this situation, and therefore asks the team to withdraw care at this point. The patient’s daughter vehemently disagrees and believes it is in the best interest of her father, the patient, to continue all care. Based on this information, what is the best course of action for the physician team?", "answer": "Listen to the patient’s wife’s wishes and withdraw care", "options": {"A": "Listen to the patient’s wife’s wishes and withdraw care", "B": "Listen to the patient’s daughter’s wishes and continue all care", "C": "Compromise between the wife and daughter and withdraw the fluids and antibiotics but keep the patient intubated", "D": "Consult the hospital ethics committee and continue all care until a decision is reached", "E": "Call other family members and consult them for their opinions"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old woman walks into the clinic for an annual check-up appointment with her family physician. When asked about any changes in her life, she states that she lost her job about 6 months ago. Since then, she has lived with her boyfriend who is also unemployed. She frequently uses laxatives and takes some over the counter medications to help her sleep. Her blood pressure is 129/87 mm Hg, respirations are 12/min, pulse is 58/min, and temperature is 36.7°C (98.1°F). Her physical exam is mostly benign. Her pupils appear mildly constricted and she appears drowsy and subdued. The physician suspects that the physical findings in this patient are caused by a substance she is likely abusing. Which of the following is the substance?", "answer": "Codeine", "options": {"A": "Ketamine", "B": "Cocaine", "C": "Codeine", "D": "Alprazolam", "E": "Clonazepam"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old woman comes to the clinic with a complaint of a severely itchy and painful rash on her hands and legs for a day. On further questioning, she revealed that she loves nature and goes on trekking to the woods frequently. She just returned from a similar trip, 2 days ago. On physical examination, a prominent rash along with multiple blisters is noted on the ventral aspect of her right forearm. A photograph of the rash is shown. Which of the following is the most likely reaction that the patient is experiencing?", "answer": "Type IV hypersensitivity reaction", "options": {"A": "Type IV hypersensitivity reaction", "B": "Type III hypersensitivity reaction", "C": "Bullous pemphigoid", "D": "Type I hypersensitivity reaction", "E": "Type II hypersensitivity reaction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy presents to his primary care physician with hip pain that started this morning. The patient claims the pain is severe and is stopping him from skateboarding. The patient recently recovered from a upper respiratory infection that he caught from his siblings but has otherwise been healthy. The patient has a past medical history of obesity. His temperature is 98.1°F (36.7°C), blood pressure is 100/55 mmHg, pulse is 90/min, respirations are 22/min, and oxygen saturation is 98% on room air. On physical exam, you note an obese boy in no acute distress. Cardiopulmonary exam is within normal limits. Inspection of the hip reveals no abnormalities or swelling. The hip exhibits a normal range of motion and physical exam only elicits minor pain. The patient's gait appears normal and pain is elicited when the patient jumps or runs. Which of the following is the best next step in management for this patient's most likely diagnosis?", "answer": "Ibuprofen and rest", "options": {"A": "Radiography", "B": "CT scan", "C": "MRI", "D": "Aspiration and broad spectrum antibiotics", "E": "Ibuprofen and rest"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An investigator is studying the incidence of sickle cell trait in African American infants. To identify the trait, polymerase chain reaction testing is performed on venous blood samples obtained from the infants. Which of the following is required for this laboratory technique?", "answer": "Initial sequence of the 3' end of a DNA strand", "options": {"A": "RNA-dependent DNA polymerase", "B": "Ligation of Okazaki fragments", "C": "Initial sequence of the 3' end of a DNA strand", "D": "Complete genome DNA sequence", "E": "Single-stranded binding proteins"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 20-year-old woman comes to the physician because of recurrent abdominal cramps, bloating, and diarrhea for 4 months. She describes her stools as greasy, foul-smelling, and difficult to flush. During this time she has had a 6-kg (13.2-lb) weight loss. She has no personal or family history of serious illness. Physical examination shows pallor and cheilitis. Laboratory studies show a hemoglobin concentration of 11 g/dL. Serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. Test of the stool for occult blood is negative and stool microscopy reveals no pathogens and no leukocytes. Analysis of a 24-hour stool sample shows 12 g of fat. The patient is asked to consume 25 g of d-xylose. Five hours later, its concentration is measured in urine at 2 g (N = > 4 g/5 h). The test is repeated after a two-week course of rifaximin, but the urinary concentration of d-xylose remains the same. Which of the following is the most likely diagnosis?", "answer": "Hypersensitivity to gliadin\n\"", "options": {"A": "Lactose intolerance", "B": "Exocrine pancreatic insufficiency", "C": "Tropheryma whipplei infection", "D": "Bacterial overgrowth in the small intestine", "E": "Hypersensitivity to gliadin\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old man presents to the emergency room complaining of shortness of breath and productive cough for a few days. He says that his sputum is mostly yellow with tiny red specks. He denies fever, chills, recent weight loss, or joint pain. He has no history of recent travel or sick contacts.  His medical history is unremarkable. He smokes a pack of cigarettes daily. He has had 3 sexual partners in the past year. His temperature is 37°C (98.6°F), blood pressure is 110/70 mm Hg, pulse is 98/min, and respirations are 20/min. On physical examination, the patient is in mild respiratory distress. Cardiopulmonary auscultation reveals diffuse bilateral rales. An HIV test is negative. His laboratory results are as follow:\nComplete blood count\nHemoglobin 12 gm/dL\nSerum chemistry\nSodium 143 mEq/L\nPotassium 4.1 mEq/L\nChloride 98 mEq/L\nBicarbonate  22 mEq/L\nBlood urea nitrogen 26 mg/dL\nCreatinine 2.3 mg/dL\nGlucose  86 mg/dL\nUrine dipstick\nProtein trace\nBlood positive\nLeukocytes negative\nNitrates negative\nWhich of the following is the most likely cause of his current condition?", "answer": "Basement membrane antibodies", "options": {"A": "Pneumocystis pneumonia", "B": "Pulmonary embolism", "C": "Heart failure", "D": "Basement membrane antibodies", "E": "Ruptured alveolar bleb"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying the clearance of respiratory particles in healthy non-smokers. An aerosol containing radio-labeled particles that are small enough to reach the alveoli is administered to the subjects via a non-rebreather mask. A gamma scanner is then used to evaluate the rate of particle clearance from the lungs. The primary mechanism of particle clearance most likely involves which of the following cell types?", "answer": "Macrophages", "options": {"A": "Goblet cells", "B": "Club cells", "C": "Type I pneumocytes", "D": "Macrophages", "E": "Neutrophils"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old woman, gravida 4, para 3, at 34 weeks' gestation comes to the physician for a prenatal visit. She feels well. She does not note any contractions or fluid from her vagina. Her third child was delivered spontaneously at 35 weeks' gestation; pregnancy and delivery of her other two children were uncomplicated. Vital signs are normal. The abdomen is nontender and no contractions are felt. Pelvic examination shows a uterus consistent in size with a 34-weeks' gestation. Ultrasonography shows the fetus in a breech presentation. The fetal heart rate is 148/min. Which of the following is the most appropriate next step in management?", "answer": "Observation", "options": {"A": "Internal cephalic version", "B": "Cesarean section", "C": "External cephalic version", "D": "Observation", "E": "Intravenous penicillin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old woman gives birth to a male child at 30 weeks of gestation. Pregnancy was complicated by polyhydramnios diagnosed on ultrasonography at 26 weeks of gestation. The baby is born vaginally weighing 1.2 kg (2.64 lb). Because he does not cry immediately after birth, endotracheal intubation is attempted to secure the airway. However, the vocal cords cannot be visualized because there is only a single opening corresponding to the esophagus. He is transferred to the NICU under bag and mask ventilation, where intubation is attempted once again by passing the endotracheal tube in the visualized opening, after which his oxygen saturation begins to improve. His temperature is 37.0ºC (98.6°F), pulse is 120/min, and respiratory rate is 42/min. On physical examination, no abnormalities are noted. Chest radiography is suggestive of respiratory distress syndrome. Which of the following most likely failed to develop in this patient?", "answer": "Fourth and sixth branchial arches", "options": {"A": "First branchial arch", "B": "Second branchial arch", "C": "Third branchial arch", "D": "Fourth and sixth branchial arches", "E": "Mesonephric duct"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 19-year-old woman presents to her primary care physician because she has been feeling increasingly lethargic over the last 6 months. Specifically, she says that she feels tired easily and has been cold even though she is wearing lots of layers. Her medical history is significant for seasonal allergies but is otherwise unremarkable. When prompted, she also says that she has a hard time swallowing food though she has no difficulty drinking liquids. Physical exam reveals a midline mass in her neck. Which of the following structures would most likely be seen if this patient's mass was biopsied?", "answer": "Follicles with colloid", "options": {"A": "Blood vessels", "B": "Follicles with colloid", "C": "Hollow epithelial duct", "D": "Lymphatic ducts", "E": "Neutrophilic invasion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old man arrives at the emergency department 30 minutes after developing rapid onset right-sided weakness and decreased sensation on the right side of his body. The patient’s wife also reports that he has had difficulty forming sentences. His wife adds that these symptoms were at their maximum within a few minutes of the incident and began to resolve almost instantaneously. The patient says he had a related episode of painless visual loss in his left eye that resolved after about 10–20 minutes about 3 months ago. His past medical history includes diabetes mellitus type 2 and essential hypertension. The patient reports a 50 pack-year smoking history. His blood pressure is 140/60 mm Hg, and his temperature is 36.5°C (97.7°F). Neurological examination is significant for a subtle weakness of the right hand. A noncontrast CT scan of the head is unremarkable, and a carotid Doppler ultrasound shows 10% stenosis of the right internal carotid artery and 50% stenosis of the left internal carotid artery. Which of the following is the expected change in resistance to blood flow through the stenotic artery most likely responsible for this patient’s current symptoms?", "answer": "It will be 16 times greater", "options": {"A": "It will double", "B": "It will be 4 times greater", "C": "It will be 8 times greater", "D": "It will be 16 times greater", "E": "No change"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 39-year-old African American woman is admitted to the hospital following a seizure with a severe post-ictal headache. She was diagnosed with breast cancer 1 year ago when she presented with a hard, rock-like, immobile mass with irregular borders accompanied by changes in the breast skin, including erythema and dimpling. She had ipsilateral mobile axillary lymphadenopathy at that time. A biopsy confirmed the diagnosis of stage 2B invasive breast cancer. Her mother died at 42 years of age due to the same type of breast cancer. A CT scan done during this admission reveals multiple metastatic lesions in the brain and liver, along with the involvement of supra- and infra-clavicular lymph nodes. Which of the following molecular profile most likely characterizes this patient?", "answer": "ER, PR, HER2 negative", "options": {"A": "Progesterone receptor (PR) positive", "B": "ER, PR, HER2 negative", "C": "Estrogen receptor (ER) positive", "D": "PR, ER, HER2 positive", "E": "HER2 positive"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 13-year-old boy is brought to the physician because of a 1-month history of progressive difficulty breathing through his nose and a 2-week history of recurrent severe nosebleeds. When he holds the right nostril shut, he is unable to breathe nasally and his sense of smell is reduced. He has a 6-year history of asthma, which is well controlled with inhaled albuterol. Vital signs are within normal limits. Nasal inspection shows a pink, lobulated mass filling the left nasal cavity. The septum is deviated to the right side. The mass bleeds on touch. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in diagnosis?", "answer": "CT scan of head with contrast", "options": {"A": "Coagulation tests", "B": "Sweat chloride test", "C": "Punch biopsy of the mass", "D": "Genetic analysis of dynein genes", "E": "CT scan of head with contrast"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 20-year-old man comes to the emergency room because of palpitations and mild dyspnea for the last 2 hours. He has had similar episodes in the past that resolved within 20 minutes, but they have been worsening since he started training for his first marathon 1 month ago. Ten years ago, he was treated for streptococcal pharyngitis with a 10-day course of penicillin. His maternal uncle passed away unexpectedly from a heart condition at age 40. He is 180 cm (5 ft 11 in) tall and weighs 85 kg (187 lb); BMI is 26.2 kg/m2. His temperature is 36.5°C (97.7°F), pulse is 70/min, respirations are 18/min, and blood pressure is 132/60 mm Hg. On examination, there is a decrescendo early diastolic murmur heard best along the left sternal border. His head slightly bobs about every second. The remainder of the examination shows no abnormalities. Which of the following is most likely to be present?", "answer": "Bicuspid aortic valve", "options": {"A": "Asymmetric septal hypertrophy", "B": "Antistreptolysin O antibodies", "C": "Myxomatous degeneration", "D": "Bicuspid aortic valve", "E": "Valve vegetation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 71-year-old man comes to the physician for a routine health maintenance examination. He feels well. He goes for a 30-minute walk three times a week and does not experience any shortness of breath or chest or leg pain on exertion. He has not had any weakness, numbness, or vision disturbance. He has diabetes that is well controlled with insulin injections. He had smoked one pack of cigarettes every day for 40 years but quit 5 years ago. He appears healthy and well nourished. His temperature is 36.3°C (97.3°F), pulse is 75/min, and blood pressure is 136/78 mm Hg. Physical examination shows normal heart sounds. There are systolic bruits over the neck bilaterally. Physical and neurologic examinations show no other abnormalities. Fasting serum studies show:\nTotal cholesterol 210 mg/dL\nHDL cholesterol 28 mg/dL\nLDL cholesterol 154 mg/dL\nTriglycerides 140 mg/dL\nGlucose 102 mg/dL\nDuplex ultrasonography of the carotid arteries shows a 85% stenosis on the left and a 55% stenosis on the right side. Which of the following is the most appropriate next step in management?\"", "answer": "Left carotid endarterectomy", "options": {"A": "Aspirin therapy only", "B": "Left carotid endarterectomy", "C": "Reassurance", "D": "Carotid artery stenting", "E": "Bilateral carotid endarterectomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old woman is brought to the emergency department after being resuscitated in the field. Her husband is with her and recalls seeing pills beside her when he was in the bathroom. He reveals she has a past medical history of depression and was recently given a prescription for smoking cessation. On physical exam, you notice a right-sided scalp hematoma and a deep laceration to her tongue. She has a poor EEG waveform indicating limited to no cerebral blood flow and failed both her apnea test and reflexes. She is found to be in a persistent vegetative state, and the health care team starts to initiate the end of life discussion. The husband states that the patient had no advance directives other than to have told her husband she did not want to be kept alive with machines. The parents want all heroic measures to be taken. Which of the following is the most accurate statement with regards to this situation?", "answer": "The patient’s husband may be appointed as her health care surrogate and may make end-of-life decisions on her behalf.", "options": {"A": "The patient’s husband may be appointed as her health care surrogate and may make end-of-life decisions on her behalf.", "B": "The patient’s parents may be appointed as her health care surrogate and may make end-of-life decisions on her behalf.", "C": "The patient’s adult daughter may be appointed as her health care surrogate and may make end-of-life decisions on her behalf.", "D": "The physician may be appointed as the patient’s health care surrogate and may make end-of-life decisions on her behalf.", "E": "An ethics committee must be appointed as the patient’s health care surrogate and may make end-of-life decisions on her behalf."}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 8-year-old girl is brought to the emergency department because of a 2-day history of low-grade fever, itchy rash, and generalized joint pain. The rash initially started in the antecubital and popliteal fossae and then spread to her trunk and distal extremities. One week ago, she was diagnosed with acute sinusitis and was started on amoxicillin. She has no history of adverse drug reactions and immunizations are up-to-date. Her temperature is 37.5°C (99.5°F), pulse is 90/min, and blood pressure is 110/70 mm Hg. Physical examination shows periorbital edema and multiple erythematous, annular plaques of variable sizes over her entire body. One of the lesions in the right popliteal fossa has an area of central clearing and the patient's mother reports that it has been present for over 24 hours. Urinalysis is normal. Which of the following is the most likely diagnosis?", "answer": "Serum sickness-like reaction", "options": {"A": "Serum sickness-like reaction", "B": "Stevens-Johnson syndrome", "C": "Pemphigus vulgaris", "D": "Drug reaction with eosinophilia and systemic symptoms", "E": "IgA vasculitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old boy presents to the clinic with his mother, who notes that the way in which he plays has changed and that he has been limping, favoring his left leg. When asked, the patient states that his left knee hurts. He is afebrile and vital signs are stable. The patient is well nourished and meeting all developmental milestones. On physical examination, the knee has a full range of motion; however, passive motion elicits pain in the left hip. An X-ray is performed and reveals a flattened left femoral head. Which of the following is the most likely diagnosis?", "answer": "Legg-Calvé-Perthes disease (LCPD)", "options": {"A": "Septic arthritis", "B": "Rickets", "C": "Legg-Calvé-Perthes disease (LCPD)", "D": "Slipped capital femoral epiphysis", "E": "Juvenile idiopathic arthritis (JIA)"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man presents to the clinic for a chronic cough over the past 4 months. The patient reports a productive yellow/green cough that is worse at night. He denies any significant precipitating event prior to his symptoms. He denies fever, chest pain, palpitations, weight changes, or abdominal pain, but endorses some difficulty breathing that waxes and wanes. He denies alcohol usage but endorses a 35 pack-year smoking history. A physical examination demonstrates mild wheezes, bibasilar crackles, and mild clubbing of his fingertips. A pulmonary function test is subsequently ordered, and partial results are shown below:\n\nTidal volume: 500 mL\nResidual volume: 1700 mL\nExpiratory reserve volume: 1500 mL\nInspiratory reserve volume: 3000 mL\n\nWhat is the functional residual capacity of this patient?", "answer": "3200 mL", "options": {"A": "2000 mL", "B": "2200 mL", "C": "3200 mL", "D": "3500 mL", "E": "4500 mL"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old man presents to his primary care physician concerned about excessive sleepiness that has persisted his entire life. He notes that he has been having difficulty with his job as a waiter because he often falls asleep suddenly during the day. He also experiences a sensation of dreaming as he goes to sleep even though he still feels awake. He sleeps about 10 hours per day and still feels tired throughout the day. The patient has even reported driving into a tree once as he fell asleep while driving. The patient often stays up late at night working on the computer. Physical exam demonstrates an obese young man who appears tired. His oropharynx demonstrates high palatal ridges and good dental hygiene. Which of the following is the best next step in management?", "answer": "Begin inhibitor of dopamine reuptake", "options": {"A": "Continuous positive airway pressure at night", "B": "Begin inhibitor of dopamine reuptake", "C": "Recommend scheduling regular naps and more time for sleep at night", "D": "Recommend to abstain from activities at night that expose the patient to blue light", "E": "Start a selective serotonin reuptake inhibitor"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 38-year-old woman presents to her primary care physician for a new patient appointment. She states that she feels well and has no current complaints. The patient recently started seeing a specialist for treatment for another medical condition but otherwise has had no medical problems. The patient lives alone and drinks 2 alcoholic beverages every night. She has had 3 sexual partners in her lifetime, uses oral contraceptive pills for contraception, and has never been pregnant. Physical exam reveals a pleasant, obese woman with normal S1 and S2 on cardiac exam. Musculoskeletal exam reveals swelling of the MCP and PIP joints of the hands as well as ulnar deviation of the fingers. Laboratory tests are ordered and results are below:\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\nAST: 95 U/L\nALT: 68 U/L\n\nWhich of the following best explains this patient's abnormal laboratory values?", "answer": "Medication", "options": {"A": "Alcohol", "B": "Bacterial infection", "C": "Medication", "D": "Obesity", "E": "Viral infection"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old woman is brought to the emergency department by her husband because of a 1-hour history of severe groin pain, nausea, and vomiting. She has had a groin swelling that worsens with standing, coughing, and straining for the past 3 months. Her pulse is 120/min. Examination shows pallor; there is swelling, erythema, and tenderness to palpation of the right groin that is centered below the inguinal ligament. The most likely cause of this patient's condition is entrapment of an organ between which of the following structures?", "answer": "Lacunar ligament and femoral vein", "options": {"A": "Linea alba and conjoint tendon", "B": "Inferior epigastric artery and rectus sheath", "C": "Conjoint tendon and inguinal ligament", "D": "Medial and median umbilical ligaments", "E": "Lacunar ligament and femoral vein"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old woman presents to her dermatologist with complaints of discoloration of the skin on her hands and wrists. She says her symptoms started about 6-months ago. Around this time, she recalls moving into her new house with her husband and children. She had to quit her job to relocate and says she is having difficulty maintaining a clean and happy household. She admits to being stressed most of the time. She was previously in good health. No significant past medical history.  The patient is afebrile and vital signs are within normal limits. Physical examination reveals patchy red, scaly skin on both hands. Upon further questioning, the patient admits to having to continuously wash her hands because she has this irrational idea that her hands are dirty. She tries her best to ignore these thoughts but eventually succumbs to wash her hands over and over to ease the anxiety. Which of the following statements is correct concerning this patient’s most likely condition?", "answer": "Symptoms are ego-dystonic", "options": {"A": "Symptoms are ego-dystonic", "B": "Patients generally lack insight", "C": "The condition is readily treatable", "D": "The condition is associated with early onset dementia", "E": "The condition rarely affects daily functioning"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2800-g (6-lb 3-oz) male newborn is born at 39 weeks’ gestation to a 22-year-old woman, gravida 2, para 2, after an uncomplicated labor and delivery. The mother did not receive prenatal care. She traveled to Brazil to visit relatives during the first trimester of her pregnancy. She has bipolar disorder treated with lithium. The newborn is at the 50th percentile for height, 25th percentile for weight, and 2nd percentile for head circumference. Neurologic examination shows spasticity of the upper and lower extremities. The wrists are fixed in flexion bilaterally. Deep tendon reflexes are 4+ and symmetric. Ophthalmoscopic examination shows focal pigmentary retinal mottling. Testing for otoacoustic emissions is negative. Which of the following measures during the mother’s pregnancy is most likely to have prevented this newborn's condition?", "answer": "Use of mosquito repellant", "options": {"A": "Avoid consumption of undercooked meat", "B": "Use of mosquito repellant", "C": "Administration of antibiotic therapy", "D": "Daily intake of prenatal vitamins", "E": "Discontinuation of mood stabilizer"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An otherwise healthy 47-year-old woman comes to the physician for the evaluation of a 4-month history of worsening fatigue and constipation. She has also noticed that her cheeks appear fuller and her voice has become hoarse. Her temperature is 36.3°C (97.3°F) and pulse is 59/min. Examination of the neck shows a painless, mildly enlarged thyroid gland. Her skin is dry and cool and her nails appear brittle. Serum studies show antibodies against thyroid peroxidase. A biopsy of the thyroid gland is most likely to show which of the following?", "answer": "Lymphocytic infiltration, Hürthle cells, and germinal centers", "options": {"A": "Large, irregular nuclei, nuclear grooves, and Psammoma bodies", "B": "Tall follicular cells, scalloped colloid, and vascular congestion", "C": "Spindle cells, pleomorphic giant cells, and mitotic figures", "D": "Multinucleated giant cells, macrophages, and degenerated follicular cells", "E": "Lymphocytic infiltration, Hürthle cells, and germinal centers"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old woman presents with abdominal pain and blood in her urine. Since the acute onset of symptoms 3 days ago, there has been no improvement. She describes the pain as moderate, sharp and burning in character, non-radiating, and localized to the suprapubic region. She also has noted some mild urinary frequency and urgency for the past 5 days, which has been getting progressively worse. She denies any flank pain, fever, chills, night sweats, dysuria, or pain on urination. The patient has a history of an abdominal leiomyosarcoma, which was diagnosed 6 months ago. The course of her disease is complicated by hepatic metastases, for which she recently started receiving a new therapy. The patient reports a 15-pack-year smoking history, but no alcohol or recreational drug use. Her temperature is 37.0℃ (98.6℉), pulse is 84/min, respiratory rate is 18/min, and blood pressure is 110/75 mm Hg. On physical examination, there is some mild suprapubic tenderness to palpation. The remainder of the exam is unremarkable. Laboratory findings include a mild leukopenia of 3,000/mm3. A urine dipstick reveals 3+ blood. Which of the following best describes the medication that could have prevented this patient’s symptoms?", "answer": "A thiol given concurrently with an antineoplastic agent to help reduce inflammation of the transitional epithelium of the bladder", "options": {"A": "Serine protease inhibitor that reduces the action of plasmin", "B": "Agent that binds to an intracellular receptor and results in the transactivation of genes that promote gluconeogenesis and has anti-inflammatory effects", "C": "A thiol given concurrently with an antineoplastic agent to help reduce inflammation of the transitional epithelium of the bladder", "D": "Monoclonal antibody that inhibits bcr-abl tyrosine kinase, blocking cell proliferation and inducing apoptosis", "E": "Antifolate that inhibits dihydrofolate reductase, inhibiting purine production necessary for cell synthesis and division"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to the physician by his parents because of a 6-week history of increased tiredness, irritability, and worsening leg pain. His parents report that he has been reluctant to walk recently because of the pain in his legs. Examination shows conjunctival pallor and diffuse petechiae. There are palpable, nontender posterior cervical and axillary lymph nodes. His hemoglobin concentration is 8.9 g/dL, leukocyte count is 45,750/mm3, and platelet count is 25,000/mm3. A bone marrow aspiration shows numerous immature cells that stain positive for CD10, CD19, and terminal deoxynucleotidyl transferase (TdT). Which of the following translocations is associated with a favorable prognosis for this patient's condition?", "answer": "t(12;21)", "options": {"A": "t(12;21)", "B": "t(15;17)", "C": "t(8;14)", "D": "t(14;18)", "E": "t(9;22)"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 37-year-old man comes to the physician because of fever, night sweats, malaise, dyspnea, and a productive cough with bloody sputum for 4 days. He was diagnosed with HIV infection 15 years ago and has not been compliant with his medication regimen. Physical examination shows diminished breath sounds over the left lung fields. An x-ray of the chest shows an ill-defined lesion in the upper lobe of the left lung. A CT-guided biopsy of the lesion is performed; a photomicrograph of the biopsy specimen stained with mucicarmine is shown. Which of the following is the most likely causal organism?", "answer": "Cryptococcus neoformans", "options": {"A": "Cocciodioides immitis", "B": "Candida albicans", "C": "Histoplasma capsulatum", "D": "Blastomyces dermatitidis", "E": "Cryptococcus neoformans"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old man presents with a history of a frequent unpleasant crawling sensation in both of his legs accompanied by an urge to move his legs for the last 6 months. He continuously moves his legs to provide him with partial relief from the unpleasant feelings in his legs. The symptoms are especially severe during the night or while lying down in bed after returning from work. These symptoms occur 3–5 days per week. He also complains of significant daytime fatigue and sleep disturbances on most days of the week. He is advised to take a polysomnography test, which reveals periodic limb movements (PLMs) during his sleep. Which of the following conditions is most associated with secondary restless legs syndrome?", "answer": "Iron deficiency anemia", "options": {"A": "Iron deficiency anemia", "B": "Pulmonary tuberculosis", "C": "Zinc deficiency", "D": "Vitamin B3 deficiency", "E": "Liver failure"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the physician because of worsening jaundice that started 8 days ago. She has had similar episodes in the past. Her father underwent a splenectomy during adolescence. Physical examination shows mild splenomegaly. Laboratory studies show:\nHemoglobin 10.1 g/dL\nWBC count 7200/mm3\nMean corpuscular volume 81 μm3\nMean corpuscular hemoglobin concentration 41% Hb/cell\nPlatelet count 250,000/mm3\nRed cell distribution width 16% (N=13%–15%)\nReticulocytes 11%\nErythrocyte sedimentation rate 10 mm/h\nSerum\nNa+ 139 mEq/L\nK+ 4.2 mEq/L\nCl- 100 mEq/L\nUrea nitrogen 16 mg/dL\nA peripheral blood smear shows red blood cells that appear round, smaller, and without central pallor. Which of the following is the most sensitive test for confirming this patient's condition?\"", "answer": "Eosin-5-maleimide binding test", "options": {"A": "Osmotic fragility test", "B": "Coombs test", "C": "Eosin-5-maleimide binding test", "D": "Hemoglobin electrophoresis", "E": "Serum ferritin level\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old obese man presents as a new patient to his primary care physician because he has been feeling tired and short of breath after recently moving to Denver. He is a former 50 pack-year smoker and has previously had deep venous thrombosis. Furthermore, he previously had a lobe of the lung removed due to lung cancer. Finally, he has a family history of a progressive restrictive lung disease. Laboratory values are obtained as follows:\n\nOxygen tension in inspired air = 130 mmHg\nAlveolar carbon dioxide tension = 48 mmHg\nArterial oxygen tension = 58 mmHg\nRespiratory exchange ratio = 0.80\nRespiratory rate = 20/min\nTidal volume = 500 mL\n\nWhich of the following mechanisms is consistent with these values?", "answer": "High altitude", "options": {"A": "High altitude", "B": "Hypoventilation", "C": "Pulmonary fibrosis", "D": "Shunt physiology", "E": "V/Q mismatch"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year old gentleman presents to the primary care physician with the chief complaint of \"feeling down\" for the last 6 weeks. He describes trouble falling asleep at night, decreased appetite, and recent feelings of intense guilt regarding the state of his personal relationships. He says that everything \"feels slower\" than it used to. He endorses having a similar four-week period of feeling this way last year. He denies thoughts of self-harm or harm of others. He also denies racing thoughts or delusions of grandeur. Which of the following would be an INAPPROPRIATE first line treatment for him?", "answer": "Electroconvulsive therapy", "options": {"A": "Psychotherapy", "B": "Citalopram", "C": "Paroxetine", "D": "Electroconvulsive therapy", "E": "Sertraline"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old man presents to the emergency department after being hit by a car while riding his bike. The patient was brought in with his airway intact, vitals stable, and with a C-collar on. Physical exam is notable for bruising over the patient’s head and a confused man with a Glasgow coma scale of 11. It is noticed that the patient has a very irregular pattern of breathing. Repeat vitals demonstrate his temperature is 97.5°F (36.4°C), blood pressure is 172/102 mmHg, pulse is 55/min, respirations are 22/min and irregular, and oxygen saturation is 94% on room air. Which of the following interventions are most likely to improve this patient's vital signs?", "answer": "Head elevation, sedation, mannitol, hyperventilation", "options": {"A": "Head elevation, norepinephrine, mannitol, hyperventilation", "B": "Head elevation, sedation, hypertonic saline, hypoventilation", "C": "Head elevation, sedation, mannitol, hyperventilation", "D": "Lower head, sedation, hypertonic saline, hyperventilation", "E": "Lower head, sedation, hypertonic saline, hypoventilation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old G0P0 female presents to her OB/GYN for a preconception visit to seek advice before becoming pregnant. A detailed history reveals no prior medical or surgical history, and she appears to be in good health currently. Her vaccination history is up-to-date. She denies tobacco or recreational drug use and admits to drinking 2 glasses of wine per week. She states that she is looking to start trying to become pregnant within the next month, hopefully by the end of January. Which of the following is NOT recommended as a next step for this patient's preconception care?", "answer": "Administer measles, mumps, rubella (MMR) vaccination", "options": {"A": "Begin 400 mcg folic acid supplementation", "B": "Recommend inactivated influenza vaccination", "C": "Obtain rubella titer", "D": "Administer measles, mumps, rubella (MMR) vaccination", "E": "Obtain varicella zoster titer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old female college student presents to the emergency department due to severe pain in her stomach after an evening of heavy drinking with her friends. The pain is located in the upper half of the abdomen, is severe in intensity, and has an acute onset. She claims to have consumed a dozen alcoholic drinks. Her past medical history is unremarkable. She has recently completed an extremely low-calorie diet which resulted in her losing 10 kg (22 lb) of body weight. Her pulse is 130/min, respirations are 26/min, and blood pressure is 130/86 mm Hg. Examination reveals a visibly distressed young female with periumbilical tenderness. Her BMI is 23 kg/m2. Laboratory tests show:\nArterial blood gas analysis\npH 7.54\nPo2 100 mm Hg\nPco2 23 mm Hg\nHCO3- 22 mEq/L\nSerum\nSodium 140 mEq/L\nPotassium 3.9 mEq/L\nChloride 100 mEq/L\nWhich of the following most likely caused her elevated pH?", "answer": "Anxiety induced hyperventilation", "options": {"A": "Alcohol induced respiratory depression", "B": "Anxiety induced hyperventilation", "C": "Pain induced hypoventilation", "D": "Renal failure induced electrolyte imbalance", "E": "Weight loss induced electrolyte imbalance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old boy presents with shortness of breath after prolonged exposure to cold air during a recent hike with his friends. Past medical history is significant for asthma, untreated because he doesn't like using medications. The patient says he is a non-smoker and occasionally drinks alcohol. On physical examination, his temperature is 37.0°C (98.6°F), pulse rate is 120/min, blood pressure is 114/76 mm Hg, and respiratory rate is 32/min. Auscultation of the chest reveals bilateral wheezing. Nebulized ipratropium bromide results in significant clinical improvement. Which of the following second messenger systems is affected by this drug?", "answer": "Phosphoinositol system", "options": {"A": "Cyclic adenosine monophosphate (cAMP) system", "B": "Cyclic guanosine monophosphate (cGMP) system", "C": "Arachidonic acid system", "D": "Phosphoinositol system", "E": "Tyrosine kinase system"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A multicentric, ambidirectional cohort study (i.e. a study that combines elements of both prospective and retrospective cohort studies) was designed in order to evaluate the relationship between nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) and exposure to patients in intensive-care units of several tertiary hospital centers. The sample included 1,000 physicians who worked in the hospital environment and who willingly underwent swabbing of their nasal vestibule and nasopharynx for active surveillance. Data of their working location was obtained from hospital administrative services. Of those who worked in the intensive care unit, 350 were colonized with MRSA, while 250 were not. Whereas in those that worked in other hospital wards, 100 were colonized with MRSA, and 300 were not. What is the relative risk of MRSA colonization in relation to working in the intensive-care unit?", "answer": "2.33", "options": {"A": "0.18", "B": "0.43", "C": "1.66", "D": "2.33", "E": "3.22"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man presents to the emergency department with abdominal distension. The patient states he has had gradually worsening abdominal distension with undulating pain, nausea, and vomiting for the past several months. The patient does not see a physician typically and has no known past medical history. He works as a farmer and interacts with livestock and also breeds dogs. His temperature is 98.7°F (37.1°C), blood pressure is 159/90 mmHg, pulse is 88/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam is notable for mild abdominal distension and discomfort to palpation of the upper abdominal quadrants. Laboratory values are ordered and are notable for a mild eosinophilia. A CT scan of the abdomen demonstrates multiple small eggshell calcifications within the right lobe of the liver. Which of the following is the most likely etiology of this patients symptoms?", "answer": "Echinococcus granulosus", "options": {"A": "Echinococcus granulosus", "B": "Enterobius vermicularis", "C": "Necator americanus", "D": "Taenia saginata", "E": "Taenia solium"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 49-year-old man presents to his physician complaining of weakness and fatigue. On exam, you note significant peripheral edema. Transthoracic echocardiogram is performed and reveals a preserved ejection fraction with impaired diastolic relaxation. A representative still image is shown in Image A. Which of the following is likely the cause of this patient's symptoms?", "answer": "Hemochromatosis", "options": {"A": "Previous treatment with doxorubicin", "B": "Hemochromatosis", "C": "Heavy, long-term alcohol consumption", "D": "History of myocardial infarction", "E": "History of a recent viral infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old male prisoner goes on a hunger strike to protest the conditions of his detainment. After 5 days without food, he suffers a seizure for which he is taken into a medical facility. On physical examination, he looks pale and diaphoretic. His blood glucose level is 50 mg/dL. In order to keep a constant supply of energy to his brain, which of the following molecules is his liver releasing into the bloodstream?", "answer": "ß-hydroxybutyric acid", "options": {"A": "ß-hydroxybutyric acid", "B": "Fatty acids", "C": "Glucose-1-phosphate", "D": "Glucose-6-phosphate", "E": "Glycogen"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old patient comes to the physician because of a 4-month history of weight loss, chest pain, dry cough, and shortness of breath on exertion. He worked as a shipbuilder for 45 years and is now retired. Since the death of his wife 2 years ago, he has lived with his daughter. He has never smoked. His temperature is 38.1°C (100.6°F), pulse is 85/min, and blood pressure is 134/82 mm Hg. Fine, end-inspiratory rales are heard at the left lung base; breath sounds are absent at the right lung base. A CT scan of the chest shows pleural thickening and a right hemothorax. Thoracocentesis confirms the diagnosis of mesothelioma. The patient and his family are informed about the poor prognosis of this condition and that the mean survival time is 1 year. The patient states that he wishes to receive radiation. He would also like to receive home hospice care but is unsure whether his health insurance would cover the costs. The patient's son, who has been assigned power of attorney, does not agree with this decision. The patient does not have a living will but states that if his heart stops beating, he wants to receive cardiopulmonary resuscitation. Which of the following disqualifies the patient from receiving hospice care?", "answer": "His life expectancy\n\"", "options": {"A": "Lack of living will", "B": "Wish for cardiopulmonary resuscitation", "C": "Uncertain coverage by health insurance", "D": "The son's objection", "E": "His life expectancy\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 8-month-old boy is brought to his pediatrician by his parents with a 12-hour history of fever and coughing. He has also been experiencing intermittent diarrhea and skin abscesses since birth. Otherwise, he has been meeting developmental milestones as expected. Analysis of this patient's sputum reveals acute angle branching fungi, and culture shows gram-positive cocci in clusters. A flow cytometry reduction test was obtained that confirmed the diagnosis. Which of the following processes is most likely defective in this patient?", "answer": "Transforming oxygen into superoxide radicals", "options": {"A": "Actin polymerization", "B": "Leukocyte migration", "C": "Maturation of B-cells", "D": "Transforming oxygen into superoxide radicals", "E": "Transforming superoxide radicals into hydrogen peroxide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old man with a genetic disorder presents for genetic counseling because he is concerned about the risk that any children he has will have the same disease as himself. Specifically, since childhood he has had difficulty breathing requiring bronchodilators, inhaled corticosteroids, and chest physiotherapy. He has also had diarrhea and malabsorption requiring enzyme replacement therapy. If his wife comes from a population where 1 in 10,000 people are affected by this same disorder, which of the following best represents the likelihood a child would be affected as well?", "answer": "1%", "options": {"A": "0.01%", "B": "0.5%", "C": "1%", "D": "2%", "E": "50%"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A medical research study is evaluating an investigational novel drug (medication 1) as compared with standard therapy (medication 2) in patients presenting to the emergency department with myocardial infarction (MI). The study enrolled a total of 3,000 subjects, 1,500 in each study arm. Follow-up was conducted at 45 days post-MI. The following are the results of the trial:\nEndpoints Medication 1 Medication 2 P-Value\nPrimary: death from cardiac causes 134 210 0.03\nSecondary: hyperkalemia 57 70 0.4\nWhat is the relative risk of death from a cardiac cause? (Round to the nearest whole number.)", "answer": "64%", "options": {"A": "36%", "B": "42%", "C": "57%", "D": "64%", "E": "72%"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old male with fluctuating levels of consciousness is brought to the emergency department by ambulance due to a fire in his home. He currently opens his eyes to voice, localizes painful stimuli, responds when asked questions, but is disoriented and cannot obey commands. The patient’s temperature is 99°F (37.2°C), blood pressure is 86/52 mmHg, pulse is 88/min, and respirations are 14/min with an oxygen saturation of 97% O2 on room air. Physical exam shows evidence of soot around the patient’s nose and mouth, but no burns, airway obstruction, nor accessory muscle use. A blood lactate is 14 mmol/L. The patient is started on intravenous fluids.\n\nWhat is the next best step in management?", "answer": "100% oxygen, hydroxycobalamin, and sodium thiosulfate", "options": {"A": "Methylene blue", "B": "Hyperbaric oxygen", "C": "Intravenous epinephrine", "D": "Sodium thiosulfate and sodium nitrite", "E": "100% oxygen, hydroxycobalamin, and sodium thiosulfate"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 75-year-old man presents to the emergency department because of pain in his left thigh and left calf for the past 3 months. The pain occurs at rest, increases with walking, and is mildly improved by hanging the foot off the bed. He has had hypertension for 25 years and type 2 diabetes mellitus for 30 years. He has smoked 30–40 cigarettes per day for the past 45 years. On examination, femoral, popliteal, and dorsalis pedis pulses are faint on both sides. The patient’s foot is shown in the image. Resting ankle-brachial index (ABI) is found to be 0.30. Antiplatelet therapy and aggressive risk factors modifications are initiated. Which of the following is the best next step for this patient?", "answer": "Urgent assessment for revascularization", "options": {"A": "Systemic anticoagulation with heparin", "B": "Cilostazol", "C": "Urgent assessment for revascularization", "D": "Exercise therapy", "E": "Amputation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old man presents to the emergency department because of difficulty breathing and sharp chest pain. The chest pain increases in intensity with lying down, and it radiates to the scapular ridge. Approximately 3 weeks ago, he had an anterior ST-elevation myocardial infarction, which was treated with intravenous alteplase. He was discharged home in a stable condition. Current vital signs include a temperature of 38.1 (100.5°F), blood pressure of 131/91 mm Hg, and pulse of 99/min. On examination, heart sounds are distant and a scratching sound is heard on the left sternal border. ECG reveals widespread concave ST elevations in the precordial leads and PR depressions in leads V2-V6. Which of the following is the most likely cause of this patient condition?", "answer": "Dressler’s syndrome", "options": {"A": "Myocarditis", "B": "Ventricular aneurysm", "C": "Recurrent infarction", "D": "Aortic dissection", "E": "Dressler’s syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-year-old girl is brought to the emergency department after swallowing a button battery that was lying on the table 1 hour ago. She has no shortness of breath or chest discomfort. Her pulse is 112/min and respirations are 30/min. Pulse oximetry on room air shows an oxygen saturation of 98%. Physical examination shows no abnormalities. An x-ray of the chest shows the battery lodged in the esophagus at the level of T2. Which of the following is the most appropriate next step in management?", "answer": "Endoscopic removal of the battery", "options": {"A": "Administer syrup of ipecac", "B": "Removal of the battery with magnet and nasogastric tube", "C": "Reassurance and observation", "D": "Administer chelation therapy", "E": "Endoscopic removal of the battery"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-week-old male presents with his parents to the pediatrician for a well-child visit. The patient’s mother reports that the patient was eating well until about one week ago, when he began vomiting after breastfeeding. His mother has tried increasing the frequency of feeds and decreasing the amount of each feed, but the vomiting seems to be getting worse. The patient now vomits after every feed. His mother states the vomitus looks like breastmilk. The patient’s mother is exclusively breastfeeding and would prefer not to switch to formula but worries that the patient is not getting the nutrition he needs. Two weeks ago, the patient was in the 75th percentile for weight and 70th for height. He is now in the 60th percentile for weight and 68th percentile for height. On physical exam, the patient has dry mucous membranes. His abdomen is soft and non-distended.\n\nWhich of the following is the best next step in management?", "answer": "Abdominal ultrasound", "options": {"A": "Abdominal ultrasound", "B": "Abdominal radiograph", "C": "Supplement breastfeeding with formula", "D": "Trial of cow's milk-free diet", "E": "Trial of empiric proton pump inhibitor"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 72-year-old man being treated for benign prostatic hyperplasia (BPH) is admitted to the emergency department for 1 week of dysuria, nocturia, urge incontinence, and difficulty initiating micturition. His medical history is relevant for hypertension, active tobacco use, chronic obstructive pulmonary disease, and BPH with multiple urinary tract infections. Upon admission, he is found with a heart rate of 130/min, respiratory rate of 19/min, body temperature of 39.0°C (102.2°F), and blood pressure of 80/50 mm Hg. Additional findings during the physical examination include decreased breath sounds, wheezes, crackles at the lung bases, and intense right flank pain. A complete blood count shows leukocytosis and neutrophilia with a left shift. A sample for arterial blood gas analysis (ABG) was taken, which is shown below.\nLaboratory test\nSerum Na+ 140 mEq/L\nSerum Cl- 102 mEq/L\nSerum K+ 4.8 mEq/L\nSerum creatinine (SCr)  2.3 mg/dL\n    Arterial blood gas  \npH 7.12\nPo2 82 mm Hg\nPco2 60 mm Hg\nSO2% 92%\nHCO3- 12.0 mEq/L\nWhich of the following best explains the patient’s condition?", "answer": "Metabolic acidosis complicated by respiratory acidosis", "options": {"A": "Metabolic acidosis complicated by respiratory acidosis", "B": "Metabolic acidosis complicated by respiratory alkalosis", "C": "Respiratory alkalosis complicated by metabolic acidosis", "D": "Respiratory acidosis complicated by metabolic alkalosis", "E": "Non-anion gap metabolic acidosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 22-year-old male varsity athlete visits the on-campus health services for shortness of breath, fatigue, and lower limb edema with onset 1 week after mild upper respiratory tract infection. Upon physical examination, his blood pressure is 100/68 mm Hg, heart rate is 120/min, respiratory rate is 23/min, and temperature is 36.4°C (97.5°F). He is referred to the nearest hospital, where his systolic pressure drops below 90 mm Hg with an S3 gallop, and he needs inotropic support in the critical care unit. A chest radiograph shows an enlarged heart, clear lungs, and effacement of the right costodiaphragmatic angle. A subsequent esophageal echocardiogram reveals severe dilation of all heart cavities, an ejection fraction of 23%, and mitral regurgitation. His family and personal history are unremarkable; therefore, an endomyocardial biopsy (EMB) is ordered. Which of the following microscopic findings would you expect in this specimen?", "answer": "Infiltration with lymphocytes", "options": {"A": "Infiltration with lymphocytes", "B": "Infiltration with eosinophils", "C": "Infiltration with giant cells", "D": "Infiltration with neutrophils", "E": "Infiltration with granulomas"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man presents to the outpatient clinic today. He has New York Heart Association class III heart failure. His current medications include captopril 20 mg, furosemide 40 mg, potassium chloride 10 mg twice daily, rosuvastatin 20 mg, and aspirin 81 mg. He reports that he generally feels well and has not had any recent worsening of his symptoms. His blood pressure is 132/85 mm Hg and heart rate is 84/min. Physical examination is unremarkable except for trace pitting edema of the bilateral lower extremities. What other medication should be added to his heart failure regimen?", "answer": "Metoprolol succinate ", "options": {"A": "Losartan", "B": "Metoprolol tartrate", "C": "Metoprolol succinate ", "D": "Isosorbide dinitrate/hydralazine ", "E": "Digoxin "}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 40-year-old, gravida 2, nulliparous woman, at 14 weeks' gestation comes to the physician because of a 6-hour history of light vaginal bleeding and lower abdominal discomfort. Eight months ago she had a spontaneous abortion at 10 weeks' gestation. Her pulse is 92/min, respirations are 18/min, and blood pressure is 134/76 mm Hg. Abdominal examination shows no tenderness or masses; bowel sounds are normal. On pelvic examination, there is old blood in the vaginal vault and at the closed cervical os. The uterus is larger than expected for the length of gestation and there are bilateral adnexal masses. Serum β-hCG concentration is 120,000 mIU/ml. Which of the following is the most appropriate next step in management?", "answer": "Transvaginal ultrasound", "options": {"A": "Transvaginal ultrasound", "B": "Chorionic villus sampling", "C": "Thyroid function tests", "D": "Fetal blood sampling", "E": "Fetal Doppler ultrasound"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old business executive presents to her primary care provider because of difficulty falling asleep on her trips. She makes 4–5 business trips from California to China every month. Her typical direct Los Angeles to Hong Kong flight leaves Los Angeles at 12:30 a.m. and reaches Hong Kong at 7:00 p.m. (local time) the next day. She complains of difficulty falling asleep at night and feeling sleepy the next morning. On arriving back in Los Angeles 2–3 days later, she feels extremely weak, has muscle soreness, and abdominal distension, all of which self-resolve in a few days. She is otherwise healthy and does not take any medications. Physical examination is unremarkable. After discussing general sleep hygiene recommendations, which of the following is the best next step for this patient’s condition?", "answer": "Melatonin", "options": {"A": "Polysomnography", "B": "Escitalopram", "C": "Temazepam", "D": "Zolpidem", "E": "Melatonin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 5-week-old infant boy presents to the pediatrician with intermittent vomiting for the last 2 weeks. The mother reports that the vomiting is non-bilious and immediately follows feeding. After vomiting, the baby is hungry and wants to feed again. The frequency of vomiting has been increasing progressively over 2 weeks. The vital signs are within normal limits. The examination of the abdomen reveals the presence of a firm mass of approx. 2 cm in length, above and to the right of the umbilicus. The mass is movable, olive-shaped, and hard on palpation. Which of the following is the most likely surgical treatment for this infant’s condition?", "answer": "Pyloromyotomy", "options": {"A": "Surgical ligation of the fistula and primary end-to-end anastomosis of the esophagus", "B": "Pyloromyotomy", "C": "Duodenoduodenostomy", "D": "Diverticulectomy", "E": "Endorectal pull-through procedure"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman with bipolar disorder visits her gynecologist because she believes she is pregnant. A urine pregnancy test is performed which confirms she is pregnant. She has mild bipolar disorder for which she takes lithium and admits that she has been taking it ‘on and off’ for 2 years now but has never had any symptoms or episodes of relapse. She says that she had not made contact with her psychiatrist for the past several months because she ‘couldn’t find any time.’ Which of the following is the next best step in the management of this patient?", "answer": "Taper lithium and provide a prescription for clonazepam as needed", "options": {"A": "Continue lithium administration through pregnancy", "B": "Taper lithium and administer valproate", "C": "Continue lithium administration through pregnancy and add lamotrigine", "D": "Taper lithium and administer carbamazepine", "E": "Taper lithium and provide a prescription for clonazepam as needed"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-year-old male is brought by his mother to the emergency room with dyspnea and fever. His mother reports a two-day history of progressive shortness of breath, malaise, and a fever with a maximum temperature of 101.6°F (38.7°C). The child has visited the emergency room three times over the past two years for pneumonia and otitis media. His family history is notable for sarcoidosis in his mother, diabetes in his father, and an early childhood death in his maternal uncle. His temperature is 101.2°F (38.4°C), blood pressure is 110/90 mmHg, pulse is 110/min, and respirations are 24/min. Physical examination reveals scant lymphoid tissue. A serological analysis reveals decreased levels of IgA, IgG, and IgM. This patient most likely has a defect in a protein that is active in which of the following cellular stages?", "answer": "Pre-B-cell", "options": {"A": "Pro-B-cell", "B": "Pre-B-cell", "C": "Immature B-cell", "D": "Mature B-cell", "E": "Plasma cell"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-month-old boy is brought to the physician for a well-child examination. He was born at 36 weeks' gestation. The mother has had no prenatal care. His 6-year-old sister has a history of osteosarcoma. He is exclusively breast fed. He is at the 60th percentile for height and weight. Vital signs are within normal limits. Examination shows inward deviation of the right eye. Indirect ophthalmoscopy shows a white reflex in the right eye and a red reflex in the left eye. Which of the following is the most appropriate next step in management?", "answer": "Fundus examination", "options": {"A": "Screen for galactosemia", "B": "Visual training exercises", "C": "CT scan of the eye", "D": "Fundus examination", "E": "Serum rubella titers"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 38-year-old woman with a history of Crohn’s disease presents with a 3-week history of weight gain. The patient also presents with a 1-month history of abdominal pain, cramping, and bloody diarrhea consistent with worsening of her inflammatory bowel disease. Past medical history is significant for Crohn’s disease diagnosed 2 years ago for which she currently takes an oral medication daily and intermittently receives intravenous medication she cannot recall the name of. Her temperature is 37.0°C (98.6°F), blood pressure is 120/90 mm Hg, pulse is 68/min, respiratory rate is 14/min, and oxygen saturation is 99% on room air. Physical examination reveals significant truncal weight gain. The patient has excessive facial hair in addition to purplish striae on her abdomen. Which of the following laboratory findings would most likely be found in this patient?", "answer": "Hypokalemia", "options": {"A": "Hyperkalemia", "B": "Normal random blood glucose levels", "C": "Metabolic acidosis", "D": "Hypoglycemia", "E": "Hypokalemia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 22-year-old man comes to the physician because of a 2-week history of cough and decreased urination. The cough was initially nonproductive, but in the last few days he has coughed up small amounts of blood-tinged sputum with clots. He has not had any fevers, chills, or weight loss. He has smoked one pack of cigarettes daily for 5 years. Pulse is 115/min and blood pressure is 125/66 mm Hg. Physical examination shows dried blood around the lips. Serum studies show a creatinine of 2.9 mg/dL. Results of a serum antineutrophil cytoplasm antibody test are negative. A biopsy specimen of the kidney is most likely to show which of the following light microscopy findings?", "answer": "Fibrin crescents in Bowman space", "options": {"A": "Neutrophilic infiltration of the capillaries", "B": "Expansion of the mesangial matrix", "C": "Thinning of the basement membrane", "D": "Fibrin crescents in Bowman space", "E": "Enlarged and hypercellular glomeruli"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man is brought to the emergency department after a motorcycle accident 30 minutes ago. He was found at the scene of the accident with a major injury to the anterior chest by a metallic object that was not removed during transport to the hospital. The medical history could not be obtained. His blood pressure is 80/50 mm Hg, pulse is 130/min, and respiratory rate is 40/min. Evaluation upon arrival to the emergency department reveals a sharp metal object penetrating through the anterior chest to the right of the sternum at the 4th intercostal space. The patient is taken to the operating room immediately, where it is shown the heart has sustained a major injury. Which of the following arteries supplies the part of the heart most likely injured in this patient?", "answer": "Right marginal artery", "options": {"A": "Right marginal artery", "B": "Left circumflex coronary artery", "C": "Left anterior descending artery", "D": "Posterior descending artery", "E": "Left coronary artery"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old man comes to the physician because of a 2 month history of difficulty sleeping and worsening fatigue. During this time, he has also had difficulty concentrating and remembering tasks at work as well as diminished interest in his hobbies. He has no suicidal or homicidal ideation. He does not have auditory or visual hallucinations. Vital signs are normal. Physical examination shows no abnormalities. Mental status examination shows a depressed mood and flat affect with slowed thinking and speech. The physician prescribes sertraline. Three weeks later, the patient comes to the physician again with only minor improvements in his symptoms. Which of the following is the most appropriate next step in management?", "answer": "Continue sertraline for 3 more weeks\n\"", "options": {"A": "Provide electroconvulsive therapy", "B": "Change medication to duloxetine", "C": "Augment with phenelzine and continue sertraline", "D": "Augment with aripiprazole and continue sertraline", "E": "Continue sertraline for 3 more weeks\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 50-year-old man presents with severe chest pain for a week. His pain increases with breathing and is localized to the right. He has tried over-the-counter medications at home, but they did not help. The patient has a 20-pack-year smoking history and currently smokes 2 pack of cigarettes daily, and he drinks 3 to 4 cans of beer daily before dinner. His temperature is 39.1°C (102.3°F), blood pressure is 127/85 mm Hg, pulse is 109/min, and respirations are 20/min. Respiratory examination shows dullness to percussion from the 7th rib inferiorly at the right midaxillary line, decreased vocal tactile fremitus, and diminished breath sounds in the same area. Chest radiograph is shown in the image. The patient is prepared for thoracocentesis. Which of the following locations would be the most appropriate for insertion of a chest tube?", "answer": "Above the superior border of the 8th rib in the midaxillary line", "options": {"A": "Above the superior border of the 7th rib in the midclavicular line", "B": "Above the superior border of the 5th rib in the midclavicular line", "C": "Below the inferior border of the 5th rib in the midaxillary line", "D": "Above the superior border of the 8th rib in the midaxillary line", "E": "Below the inferior border of the 7th rib in the midaxillary line"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 13-year-old girl is brought to the physician by her mother because of a change in behavior. The mother reports that over the past 6 months, her daughter has had frequent mood swings. Sometimes, she is irritable for several days and loses her temper easily. In between these episodes, she behaves “normal,” spends time with her friends, and participates in gymnastics training twice a week. The mother has also noticed that her daughter needs more time than usual to get ready for school. Sometimes, she puts on excessive make-up. One month ago, her teacher had informed the parents that their daughter had skipped school and was seen at the local mall with one of her classmates instead. The patient reports that she often feels tired, especially when she has to wake up early for school. On the weekends, she sleeps until 1 pm. Menses have occurred at 15- to 45-day intervals since menarche at the age of 12 years; they are not associated with abdominal discomfort or functional impairment. Physical examination shows no abnormalities. Which of the following is the most likely explanation for the patient's behavior?", "answer": "Normal behavior", "options": {"A": "Borderline personality disorder", "B": "Normal behavior", "C": "Major depressive disorder", "D": "Premenstrual syndrome", "E": "Bipolar disorder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 44-year-old woman with recurrent urinary tract infections is brought to the emergency department by ambulance after sudden onset of severe headache 30 minutes ago. She has a history of occasional, mild headaches in the morning. There is no other history of serious illness. Both her father and her paternal grandmother died of chronic kidney disease. Her temperature is 37.2°C (99.1°F) and blood pressure is 145/90 mm Hg. Physical examination shows neck stiffness. When her hip is flexed, she is unable to fully extend her knee because of pain. Lumbar puncture performed 12 hours after headache onset yields 10 mL of yellow-colored fluid with no leukocytes. Which of the following is the most likely predisposing factor for this patient's current condition?", "answer": "Saccular aneurysm\n\"", "options": {"A": "Arterial atherosclerosis", "B": "Bacterial infection", "C": "Hypercoagulable state", "D": "Cerebral atrophy", "E": "Saccular aneurysm\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 56-year-old man presents to the family medicine office since he has been having difficulty keeping his blood pressure under control for the past month. He has a significant medical history of hypertension, coronary artery disease, and diabetes mellitus. He has a prescription for losartan, atenolol, and metformin. The blood pressure is 178/100 mm Hg, the heart rate is 92/min, and the respiratory rate is 16/min. The physical examination is positive for a grade II holosystolic murmur at the left sternal border. He also has diminished sensation in his toes. Which of the following statements is the most effective means of communication between the doctor and the patient?", "answer": "“What is causing your blood pressure to be elevated?”", "options": {"A": "“Have you been taking your medications as prescribed?”", "B": "“Why are you not taking your medication?”", "C": "“What is causing your blood pressure to be elevated?”", "D": "“You are taking your medications as prescribed, aren’t you?”", "E": "“Would you like us to consider trying a different medication for your blood pressure?”"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Twenty minutes after delivery by lower segment cesarean section at 38 weeks' gestation, a 4630-g (10-lb 3-oz) male newborn has respiratory distress. Apgar scores were 7 and 8 at 1 and 5 minutes, respectively. Pregnancy was complicated by gestational diabetes mellitus. His temperature is 36.9°C (98.4°F), pulse is 155/min and respirations are 72/min. Pulse oximetry on room air shows an oxygen saturation of 88%. Grunting and moderate intercostal and subcostal retractions are present. Diffuse crackles are heard on auscultation of the chest. An x-ray of the chest shows increased lung volume and fluid within the interlobar fissures. Which of the following is the most appropriate next step in management?", "answer": "Supportive care", "options": {"A": "Supportive care", "B": "Broad-spectrum antibiotic therapy", "C": "Continuous positive airway pressure", "D": "Surfactant therapy", "E": "Nitric oxide therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old gravida 2, para 1 presents to her physician at 21 weeks gestation with decreased sensitivity, tingling, and pain in her right hand that is worse at night and is partially relieved by shaking her hand. She developed these symptoms gradually over the past month. She does not report any trauma to her extremities, neck, or spine. The physical examination shows a normal range of motion of the neck, spine, and extremities. On neurologic examination, the patient has 2+ biceps and triceps reflexes. She has decreased pressure and temperature sensitivity over the palmar surface of the 1st, 2nd, and 3rd fingers. Wrist flexion and tapping the skin over the flexor retinaculum trigger exacerbation of the symptoms. Which of the following statements about the patient’s condition is correct?", "answer": "Immobilization (for example, splinting) should improve the reported outcome in this patient.", "options": {"A": "This is a fairly uncommon condition in pregnant women.", "B": "Pre-pregnancy obesity increases risk of developing this condition during pregnancy.", "C": "Corticosteroid injections are contraindicated in pregnant women for management of this condition.", "D": "If this condition has occurred in the second or third trimester of pregnancy, it is unlikely to resolve after the completion of pregnancy.", "E": "Immobilization (for example, splinting) should improve the reported outcome in this patient."}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 15-year-old female is brought to the emergency room with high fever and confusion. She complains of chills and myalgias, and physical examination reveals a petechial rash. Petechial biopsy reveals a Gram-negative diplococcus. The patient is at greatest risk for which of the following?", "answer": "Bilateral adrenal destruction", "options": {"A": "Bilateral adrenal destruction", "B": "Pelvic inflammatory disease", "C": "Septic arthritis", "D": "Osteomyelitis", "E": "Acute endocarditis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man with a history of diabetes, hypertension, hyperlipidemia, and obesity is transferred from the cardiac catheterization lab to the cardiac critical care unit after sustaining a massive myocardial infarction. He received a bare metal stent and has now stabilized. However, shortly after being transferred, he reports palpitations. EKG reveals ventricular tachycardia. Your attending wishes to start an anti-arrhythmic drug with a high selectivity for ischemic cardiac myocytes. You call the nurse and ask her to begin intravenous:", "answer": "Lidocaine", "options": {"A": "Quinidine", "B": "Lidocaine", "C": "Dofetilide", "D": "Procainamide", "E": "Flecainide"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 13-year-old girl is brought to the physician by her father because of a worsening pruritic rash for 2 days. Five weeks ago, she was diagnosed with juvenile myoclonic epilepsy and treatment with lamotrigine was begun. Her immunizations are up-to-date. Her temperature is 38.8°C (101.8°F). Physical examination shows facial edema and a partially confluent morbilliform rash over the face, trunk, and extremities. There is swelling of the cervical and inguinal lymph nodes and hepatomegaly. Further evaluation is most likely to show which of the following?", "answer": "Increased absolute eosinophil count", "options": {"A": "Fragmented red blood cells", "B": "Increased absolute eosinophil count", "C": "Positive heterophile antibody test", "D": "Anti-measles IgM antibodies", "E": "Elevated antistreptolysin-O titer"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 9-year-old boy is brought to his physician for behavioral problems in school. The patient’s parents have noted that he often will “shake his hands” abnormally at times and does so on his own without provocation. This has persisted for the past year. Additionally, the child has made loud grunting sounds in school that disturb the other students and the teacher. The patient has a past medical history of asthma and atopic dermatitis, and his current medications include ibuprofen, albuterol, and topical corticosteroids during flares. On physical exam, you note an active young child who is playing with toys in the office. You observe the grunting sounds he makes at this office visit. The child seems mistrustful, does not reply to your questions, and does not look you in the eyes. Which of the following is most likely also found in this patient?", "answer": "Excessive hand washing", "options": {"A": "Auditory hallucinations", "B": "Cough that occurs only at night", "C": "Excessive hand washing", "D": "Mental retardation", "E": "Poor communication skills"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 52-year-old man presents to the Emergency Department because of bilateral leg swelling and puffiness of both eyes in the morning. His symptoms started about 2 weeks ago. He denies smoking or alcohol use and his family history is noncontributory. Today, his vital signs include a temperature of 36.8°C (98.2°F), blood pressure of 162/87 mm Hg, and a pulse of 85/min. On physical examination, he is jaundiced and there is hepatosplenomegaly and 2+ lower extremity edema up to the mid-thigh. Laboratory results are shown:\nAnti-HCV\nreactive\nSerum albumin\n3 g/dL\nUrine dipstick\n3+ protein\nUrinalysis\n10–15 red blood cells/high power field and red cell casts\nWhich of the following is a feature of this patient’s condition?", "answer": "Subendothelial immune complex deposits", "options": {"A": "Subendothelial immune complex deposits", "B": "Phospholipase A2 receptor antibodies", "C": "Normal complement level", "D": "Renal vasoconstriction and altered autoregulation", "E": "Few immune complex deposits"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 61-year-old woman presents to her primary care physician complaining of left-sided facial pain that started yesterday. She describes the pain as stinging, burning, and constant. It does not worsen with jaw movement or chewing. Her past medical history includes hyperlipidemia and multiple sclerosis (MS), and she had chickenpox as a child but received a shingles vaccination last year. Medications include simvastatin and glatiramer acetate. The patient’s last MS flare was 5 weeks ago, at which time she received a prednisone burst with taper. At this visit, her temperature is 99.9 °F (37.7°C), blood pressure is 139/87 mmHg, pulse is 82/min, and respirations are 14/min. On exam, there is no rash or skin change on either side of the patient’s face. Gentle palpation of the left cheek and mandible produce significant pain, but there is full range of motion in the jaw. Which of the following medications is the most likely to prevent long-term persistence of this patient’s pain?", "answer": "Oral acyclovir", "options": {"A": "Carbamazepine", "B": "Amitriptyline", "C": "Oral acyclovir", "D": "Topical corticosteroids", "E": "Gabapentin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old woman comes to the physician because of a 2-day history of a red, itchy, burning rash on her vulva. She has had three similar episodes over the last two years that have all self-resolved. Genitourinary examination shows a small area of erythema with an overlying cluster of vesicles on the inside surface of the vulva. Latent infection of which of the following is most likely responsible for this patient's recurrent symptoms?", "answer": "Sensory neurons", "options": {"A": "Macrophages", "B": "Sensory neurons", "C": "Monocytes", "D": "Astrocytes", "E": "T cells"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A researcher is studying gamete production and oogenesis. For her experiment, she decides to cultivate primary oocytes just prior to ovulation and secondary oocytes just prior to fertilization. When she examines these gametes, she will find that the primary oocytes and secondary oocytes are arrested in which phases of meiosis, respectively?", "answer": "Prophase I; metaphase II", "options": {"A": "Interphase I; prophase II", "B": "Metaphase I; metaphase II", "C": "Metaphase I; prophase II", "D": "Anaphase I; anaphase II", "E": "Prophase I; metaphase II"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 51-year-old woman presents to the primary care clinic complaining of trouble sleeping. She reports that she has episodes of “overheating” and “sweating” during the day and at night. The nightly episodes keep her from staying asleep. She also explains how embarrassing it is when she suddenly becomes hot and flushed during work meetings. The patient becomes visibly upset and states that she is worried about her marriage as well. She says she has been fighting with her husband about not going out because she is “too tired.” They have not been able to have sex the past several months because “it hurts.” Labs are drawn, as shown below:\n\nFollicle stimulating hormone (FSH): 62 mIU/mL\nEstridiol: 34 pg/mL\nProgesterone: 0.1 ng/mL\nLuteinizing hormone (LH): 46 mIU/mL\nFree testosterone: 2.1 ng/dL\n\nWhich of the following contributes most to the production of estrogen in this patient?", "answer": "Adipose tissue", "options": {"A": "Adipose tissue", "B": "Adrenal glands", "C": "Bartholin glands", "D": "Mammary glands", "E": "Ovaries"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 67-year-old man comes to the physician because of progressive burning pain and intermittent “electrical shocks” in his right chest for 3 months. Over the last 2 weeks, the pain has increased to an extent that he can no longer tolerate clothing on the affected area. Three months ago, he had a rash around his right nipple and axilla that resolved a week later. The patient had a myocardial infarction 2 years ago. He has smoked one packs of cigarettes daily for 47 years. Current medications include aspirin, simvastatin, metoprolol, and ramipril. His temperature is 36.9°C (97.9°F), pulse is 92/min, and blood pressure is 150/95 mm Hg. Examination shows increased sensation to light touch over the right chest. The remainder of the physical examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Oral gabapentin", "options": {"A": "Sublingual nitrates", "B": "Oral tricyclic antidepressants", "C": "Oral famciclovir", "D": "Intrathecal glucocorticoids", "E": "Oral gabapentin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 51-year-old woman is brought to the emergency department because of an aggressive cough with copious amounts of thick, foamy, yellow-green sputum. She says she has had this cough for about 11 years with exacerbations similar to her presentation today. She also reports that her cough is worse in the morning. She was evaluated multiple times in the past because of recurrent bouts of bronchitis that have required treatment with antibiotics. She is a non-smoker. On physical examination, the blood pressure is 125/78 mm Hg, pulse rate is 80/min, respiratory rate is 16/min, and temperature is 36.7°C (98.0°F). Chest auscultation reveals crackles and wheezing over the right middle lobe and the rest of her physical examinations are normal. The chest X-ray shows irregular opacities in the right middle lobe and diffuse airway thickening. Based on this history and physical examination, which of the following is the most likely diagnosis?", "answer": "Bronchiectasis", "options": {"A": "Tuberculosis", "B": "Alpha-1-antitrypsin deficiency", "C": "Bronchiectasis", "D": "Chronic obstructive pulmonary disease", "E": "Chronic bronchitis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old woman presents to her primary care provider complaining of intermittent fever and loss of appetite for the past 2 weeks. She is also concerned about painful genital lesions. Past medical history is noncontributory. She takes oral contraceptives and a multivitamin daily. She has had two male sexual partners in her lifetime and uses condoms inconsistently. She admits to being sexually active with 2 partners in the last 3 months and only using condoms on occasion. Today, her vitals are normal. On pelvic exam, there are red-rimmed, fluid-filled blisters over the labia minora (as seen in the photograph below) with swollen and tender inguinal lymph nodes. Which of the following is the most likely diagnosis of this patient?", "answer": "Genital herpes", "options": {"A": "Syphilis", "B": "Condyloma acuminata", "C": "Gonorrhea", "D": "Genital herpes", "E": "Trichomoniasis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman comes to the emergency department because of increasing abdominal pain with associated nausea and vomiting. The symptoms began suddenly after having intercourse with her partner six hours ago. There is no associated fever, diarrhea, vaginal bleeding, or discharge. Menarche was at the age of 13 years and her last menstrual period was 4 weeks ago. She uses combination contraceptive pills. She had an appendectomy at the age of 12. Her temperature is 37.5°C (99.5°F), pulse is 100/min, respirations are 22/min, and blood pressure is 110/70 mm Hg. Abdominal examination shows severe right lower quadrant tenderness with associated rebound and guarding. Pelvic examination shows scant, clear vaginal discharge and right adnexal tenderness. There is no cervical wall motion tenderness. Her hemoglobin concentration is 10.5 g/dL, leukocyte count is 9,000/mm3, and platelet count is 250,000/mm3. A urine pregnancy test is negative. Which of the following imaging findings is most likely?", "answer": "Decreased ovarian blood flow on doppler", "options": {"A": "Echogenic tubal ring", "B": "Decreased ovarian blood flow on doppler", "C": "Complex, echogenic intrauterine mass", "D": "Distended fallopian tube with incomplete septations", "E": "Increased ovarian blood flow on doppler"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 17-year-old girl presents with significant weight loss over the last few months. There is a positive family history of Hodgkin lymphoma and hyperthyroidism. Her blood pressure is 100/65 mm Hg, pulse rate is 60/min, and respiratory rate is 17/min. Her weight is 41 kg and height is 165 cm. On physical examination, the patient is ill-appearing. Her skin is dry, and there are several patches of thin hair on her arm. No parotid gland enlargement is noted and her knuckles show no signs of trauma. Laboratory findings are significant for the following:\nHemoglobin  10.1 g/dL\nHematocrit 37.7%\nLeukocyte count  5,500/mm³\nNeutrophils 65% \nLymphocytes  30%\nMonocytes 5%\nMean corpuscular volume  65.2 µm³\nPlatelet count 190,000/mm³\nErythrocyte sedimentation rate  10 mm/h\nWhich of the following findings is associated with this patient’s most likely condition?", "answer": "Amenorrhea", "options": {"A": "Amenorrhea", "B": "Dental caries", "C": "Diarrhea", "D": "Abdominal striae", "E": "Parotid gland enlargement"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 61-year-old woman comes to the emergency department because of a 2-hour history of headache, nausea, blurred vision, and pain in the left eye. She has had similar symptoms in the past. Her vital signs are within normal limits. The left eye is red and is hard on palpation. The left pupil is mid-dilated and nonreactive to light. Administration of which of the following drugs should be avoided in this patient?", "answer": "Epinephrine", "options": {"A": "Acetazolamide", "B": "Epinephrine", "C": "Pilocarpine", "D": "Apraclonidine", "E": "Timolol"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Two hours after undergoing a left femoral artery embolectomy, an obese 63-year-old woman has severe pain, numbness, and tingling of the left leg. The surgery was without complication and peripheral pulses were weakly palpable postprocedure. She has type 2 diabetes mellitus, peripheral artery disease, hypertension, and hypercholesterolemia. Prior to admission, her medications included insulin, enalapril, carvedilol, aspirin, and rosuvastatin. She appears uncomfortable. Her temperature is 37.1°C (99.3°F), pulse is 98/min, and blood pressure is 132/90 mm Hg. Examination shows a left groin surgical incision. The left lower extremity is swollen, stiff, and tender on palpation. Dorsiflexion of her left foot causes severe pain in her calf. Femoral pulses are palpated bilaterally. Pedal pulses are weaker on the left side as compared to the right side. Laboratory studies show:\nHemoglobin 12.1\nLeukocyte count 11,300/mm3\nPlatelet count 189,000/mm3\nSerum\nGlucose 222 mg/dL\nCreatinine 1.1 mg/dL\nUrinalysis is within normal limits. Which of the following is the most likely cause of these findings?\"", "answer": "Reperfusion injury", "options": {"A": "Deep vein thrombosis", "B": "Reperfusion injury", "C": "Rhabdomyolysis", "D": "Cholesterol embolism", "E": "Cellulitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A regional academic medical center has 10 cases of adenovirus in the span of a week among its ICU patients. A committee is formed to investigate this outbreak. They are tasked with identifying the patients and interviewing the care providers to understand how adenovirus could have been spread from patient to patient. This committee will review charts, talk to the care provider teams, and investigate current patient safety and sanitation measures in the ICU. The goal of the committee is to identify weaknesses in the current system and to put in place a plan to help prevent this sort of outbreak from reoccurring in the future. The committee is most likely using what type of analysis?", "answer": "Root cause analysis", "options": {"A": "Failure mode and effects analysis", "B": "Root cause analysis", "C": "Algorithmic analysis", "D": "Simulation", "E": "Heuristic analysis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 9-year-old boy who recently emigrated from sub-Saharan Africa is brought to the physician because of a 2-day history of fever, chills, and productive cough. His mother reports that he has had several episodes of painful swelling of his fingers during infancy that resolved with pain medication. His immunization status is unknown. His temperature is 39.8°C (103.6°F). Examination shows pale conjunctivae and yellow sclerae. There are decreased breath sounds and inspiratory crackles over the left lower lung fields. His hemoglobin concentration is 7 g/dL. Blood cultures grow optochin-sensitive, gram-positive diplococci. A deficiency in which of the following most likely contributed to this patient's infection?", "answer": "Bacterial clearance", "options": {"A": "Bacterial clearance", "B": "Immunoglobulin A action", "C": "Respiratory burst", "D": "Complement production", "E": "T cell differentiation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 78-year-old man is brought to the physician by his daughter for a follow-up examination. The daughter noticed that he has gradually become more forgetful and withdrawn over the last year. He frequently misplaces his car keys and forgets the names of his neighbors, whom he has known for 30 years. He has difficulty recalling his address and telephone number. He recently had an episode of urinary and fecal incontinence. Last week, his neighbor found him wandering the parking lot of the grocery store. He has hypertension and hyperlipidemia. He had smoked one pack of cigarettes daily for 40 years but quit 18 years ago. His current medications include hydrochlorothiazide and atorvastatin. He appears healthy; BMI is 23 kg/m2. His temperature is 37.2°C (99.0°F), pulse is 86/min, respirations are 14/min, and blood pressure is 136/84 mm Hg. Mini-mental state examination score is 19/30. He is not bothered by his forgetfulness. Cranial nerves II–XII are intact. He has 5/5 strength and full sensation to light touch in all extremities. His patellar, Achilles, and biceps reflexes are 2+ bilaterally. His gait is steady. MRI scan of the brain shows ventriculomegaly and prominent cerebral sulci. Which of the following is the most appropriate pharmacotherapy?", "answer": "Donepezil", "options": {"A": "Donepezil", "B": "Thiamine", "C": "Acetazolamide", "D": "Sertraline", "E": "Memantine\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man with a 5-year history worsening shortness of breath and cough comes to the physician for a follow-up examination. He has never smoked. His pulse is 75/min, blood pressure is 130/65 mm Hg, and respirations are 25/min. Examination shows an increased anteroposterior diameter of the chest. Diminished breath sounds and wheezing are heard on auscultation of the chest. An x-ray of the chest shows widened intercostal spaces, a flattened diaphragm, and basilar-predominant bullous changes of the lungs. This patient is at increased risk for which of the following complications?", "answer": "Hepatocellular carcinoma", "options": {"A": "Hepatocellular carcinoma", "B": "Churg-Strauss syndrome", "C": "Pulmonary fibrosis", "D": "Bronchogenic carcinoma", "E": "Bronchiolitis obliterans"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 61-year-old obese man with recently diagnosed hypertension returns to his primary care provider for a follow-up appointment and blood pressure check. He reports feeling well with no changes to since starting his new blood pressure medication 1 week ago. His past medical history is noncontributory. Besides his blood pressure medication, he takes atorvastatin and a daily multivitamin. The patient reports a 25-pack-year smoking history and is a social drinker on weekends. Today his physical exam is normal. Vital signs and laboratory results are provided in the table.\nLaboratory test\n2 weeks ago Today\nBlood pressure 159/87 mm Hg Blood pressure 164/90 mm Hg\nHeart rate 90/min Heart rate 92/min\nSodium 140 mE/L Sodium 142 mE/L\nPotassium 3.1 mE/L Potassium 4.3 mE/L\nChloride 105 mE/L Chloride 103 mE/L\nCarbon dioxide 23 mE/L Carbon dioxide 22 mE/L\nBUN 15 mg/dL BUN 22 mg/dL\nCreatinine 0.80 mg/dL Creatinine 1.8 mg/dL\nMagnetic resonance angiography (MRA) shows a bilateral narrowing of renal arteries. Which of the following is most likely this patient’s new medication that caused his acute renal failure?", "answer": "Captopril", "options": {"A": "Verapamil", "B": "Hydralazine", "C": "Clonidine", "D": "Captopril", "E": "Hydrochlorothiazide"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A startup is working on a novel project in which they claim they can replicate the organelle that is defective in MELAS syndrome. Which of the following metabolic processes must they be able to replicate if their project is to mimic the metabolic processes of this organelle?", "answer": "Fatty acid (beta) oxidation", "options": {"A": "Glycolysis", "B": "Fatty acid synthesis", "C": "Fatty acid (beta) oxidation", "D": "Hexose monophaste shunt", "E": "Cholesterol synthesis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old man with a history of hypertension, hyperlipidemia, and obesity presents to you in clinic for a yearly physical. His current medication regimen includes a beta blocker, angiotensin converting enzyme inhibitor, and a statin. You review his recent lab work and note that despite being on a maximum statin dose, his LDL cholesterol remains elevated. You decide to prescribe another medication to improve his lipid profile. One month later, you receive a telephone call from your patient; he complains of turning bright red and feeling \"scorching hot\" every time he takes his medications. You decide to prescribe the which of the following medications to alleviate his symptoms:", "answer": "Aspirin", "options": {"A": "Diphenhydramine", "B": "Aspirin", "C": "Coenzyme Q10", "D": "Hydroxyzine", "E": "Acetaminophen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-week-old newborn is brought to the physician for a follow-up examination. He was born at term and the pregnancy was uncomplicated. His mother says he has been feeding well and passing adequate amounts of urine. He appears healthy. He is at the 60th percentile for length and 40th percentile for weight. His temperature is 37.3°C (99.1°F), pulse is 130/min, respirations are 49/min and blood pressure is 62/40 mm Hg. A thrill is present over the third left intercostal space. A 5/6 holosystolic murmur is heard over the left lower sternal border. An echocardiography shows a 3-mm membranous ventricular septal defect. Which of the following is the most appropriate next step in management?", "answer": "Outpatient follow-up", "options": {"A": "Amoxicillin therapy", "B": "Prostaglandin E1 therapy", "C": "Outpatient follow-up", "D": "Indomethacin therapy", "E": "Cardiac catheterization"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man comes to the emergency department because of severe chest pain for the past hour. The patient describes the pain as located in the middle of his chest, tearing in quality, and radiating to his back. He has a history of hypertension, hyperlipidemia, and type 2 diabetes mellitus. He has smoked a pack of cigarettes daily for the past 30 years. He drinks 2–3 beers daily. He used cocaine in his 30s, but he has not used any illicit drugs for the past 15 years. Medications include enalapril, atorvastatin, and metformin. He says that he has not been taking his medications on a regular basis. He is 174 cm (5 ft 9 in) tall and weighs 98 kg (216 lb); BMI is 32 kg/m2. His pulse is 80/min, and blood pressure is 150/90 mm Hg in his right arm and 180/100 mm Hg in his left arm. Cardiac examination shows a high-pitched, blowing, decrescendo early diastolic murmur. An ECG shows no abnormalities. An x-ray of the chest shows a widened mediastinum. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Hypertension", "options": {"A": "Diabetes mellitus", "B": "Age", "C": "Hyperlipidemia", "D": "Hypertension", "E": "History of smoking"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year-old boy is brought to the pediatrician because his mother is concerned about recent behavioral changes. His mother states that she has started to notice that he is slurring his speech and seems to be falling more than normal. On exam, the pediatrician observes the boy has pes cavus, hammer toes, and kyposcoliosis. Based on these findings, the pediatrician is concerned the child has a trinucleotide repeat disease. Which of the following trinucleotide repeats is this child most likely to possess?", "answer": "GAA", "options": {"A": "CGG", "B": "GAA", "C": "CAG", "D": "CTG", "E": "GCC"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old woman presents to her primary care physician for recent onset headaches, weight loss, and restlessness. Her symptoms started yesterday, and since then she has felt sweaty and generally uncomfortable. The patient’s past medical history is unremarkable except for a recent viral respiratory infection which resolved on its own. The patient is not currently on any medications. Her temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 110/min, respirations are 14/min, and oxygen saturation is 98% on room air. On physical exam, you see a sweaty and uncomfortable woman who has a rapid pulse. The patient demonstrates no abnormalities on HEENT exam. The patient’s laboratory values are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 8,500/mm^3 with normal differential\nPlatelet count: 195,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 102 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.2 mg/dL\nTSH: .03 mIU/L\nAST: 12 U/L\nALT: 10 U/L\n\nThe patient is prescribed propranolol and proplythiouracil. She returns 1 week later complaining of severe fatigue. Laboratory values are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 8,500/mm^3 with normal differential\nPlatelet count: 195,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 102 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.2 mg/dL\nTSH: 6.0 mIU/L\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following is the best next step in management?", "answer": "Discontinue current medications", "options": {"A": "Decrease dose of current medications", "B": "Discontinue current medications and add ibuprofen", "C": "Discontinue current medications and add T4", "D": "Discontinue medications and add T3", "E": "Discontinue current medications"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old woman comes to the physician because of recurrent thoughts that cause her severe distress. She describes these thoughts as gory images of violent people entering her flat with criminal intent. She has had tremors and palpitations while experiencing these thoughts and must get up twenty to thirty times at night to check that the door and windows have been locked. She says that neither the thoughts nor her actions are consistent with her “normal self”. She has a history of general anxiety disorder and major depressive disorder. She drinks 1–2 alcoholic beverages weekly and does not smoke or use illicit drugs. She takes no medications. She appears healthy and well nourished. Her vital signs are within normal limits. On mental status examination, she is calm, alert and oriented to person, place, and time. She describes her mood as \"\"good.\"\"; her speech is organized, logical, and coherent. Which of the following is the most appropriate next step in management?\"", "answer": "Sertraline", "options": {"A": "Olanzapine", "B": "Venlafaxine", "C": "Risperidone", "D": "Phenelzine", "E": "Sertraline"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 41-year-old man presents to a New Mexico emergency department with a 12 hour history of shortness of breath and a nonproductive cough. He says that last week he experienced fevers, chills, fatigue, and myalgias but assumed that he simply had a cold. The symptoms went away after 3 days and he felt fine for several days afterward until he started experiencing shortness of breath even at rest. He works as an exterminator and recently had a job in a rodent infested home. Physical exam reveals a thin, tachypneic man with diffuse rales bilaterally. The most likely cause of this patient's symptoms is associated with which of the following?", "answer": "Decreased serum albumin level", "options": {"A": "Binding to sialic acid residues in human cells", "B": "Cerebral spinal fluid pleocytosis", "C": "Decreased serum albumin level", "D": "Safety pin-shaped organisms on peripheral blood smear", "E": "Widened mediastinum on chest radiograph"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old woman with a history of subarachnoid hemorrhage is brought to the emergency department because of shortness of breath and sharp chest pain that worsens on inspiration. She underwent surgery for a hip fracture 3 weeks ago. Her pulse is 110/min, respirations are 20/min, and blood pressure is 112/74 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 92%. The lungs are clear to auscultation and there is no jugular venous distention. A ventilation and perfusion scan shows a small perfusion defect in the left lower lung. A drug with which of the following mechanisms of action is most appropriate for this patient?", "answer": "Activation of antithrombin III", "options": {"A": "Inhibition of vitamin K epoxide reductase", "B": "Inhibition of cyclooxygenase", "C": "Inhibition of adenosine diphosphate receptors", "D": "Activation of plasminogen", "E": "Activation of antithrombin III"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old girl is brought to the emergency department by her friends who were at a party with her and found her unconscious in the bathroom. They admit that alcohol was present at the party. The patient's blood pressure is 118/78 mm Hg, pulse is 40/min, respiratory rate is 16/min, and temperature is 36.7°C (98.1°F). On physical examination, she is unresponsive to verbal commands but does respond to noxious stimuli. Her pupils are pinpoint and her mucous membranes are moist. Her heart is bradycardic without murmurs, and her respiratory rate is slowed but clear to auscultation. What is the most likely cause of her symptoms?", "answer": "Overdose of heroin", "options": {"A": "Alcohol poisoning", "B": "Overdose of heroin", "C": "Ethylene glycol ingestion", "D": "Overdose of cocaine", "E": "3,4-methylenedioxy-methamphetamine (MDMA) ingestion"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 44-year-old woman presents with increased thirst and frequent urination that started 6 months ago and have progressively worsened. Recently, she also notes occasional edema of the face. She has no significant past medical history or current medications. The patient is afebrile and the rest of the vital signs include: blood pressure is 120/80 mm Hg, heart rate is 61/min, respiratory rate is 14/min, and temperature is 36.6°C (97.8°F). The BMI is 35.2 kg/m2. On physical exam, there is 2+ pitting edema of the lower extremities and 1+ edema in the face. There is generalized increased deposition of adipose tissue present that is worse in the posterior neck, upper back, and shoulders. There is hyperpigmentation of the axilla and inguinal areas. The laboratory tests show the following findings:\nBlood\nErythrocyte count 4.1 million/mm3\nHgb 12.9 mg/dL\nLeukocyte count 7,200/mm3\nPlatelet count 167,000/mm3\nFasting blood glucose 141 mg/dL (7.8 mmol/L)\nCreatinine 1.23 mg/dL (108.7 µmol/L)\nUrea nitrogen 19 mg/dL (6.78 mmol/L)\nUrine dipstick\nGlucose +++\nProtein ++\nBacteria Negative\nThe 24-hour urine protein is 0.36 g. Which of the following medications is the best treatment for this patient’s condition?", "answer": "Enalapril", "options": {"A": "Enalapril", "B": "Insulin", "C": "Metoprolol", "D": "Furosemide", "E": "Mannitol"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-week-old newborn is brought to the pediatrician by his mother. His mother is concerned about her son’s irritability and vomiting, particularly after breastfeeding him. The infant was born at 39 weeks via spontaneous vaginal delivery. His initial physical was benign. Today the newborn appears mildly jaundiced with palpable hepatomegaly, and his eyes appear cloudy, consistent with the development of cataracts. The newborn is also in the lower weight-age percentile. The physician considers a hereditary enzyme deficiency and orders blood work and a urinalysis to confirm his diagnosis. He recommends that milk and foods high in galactose and/or lactose be eliminated from the diet. Which of the following is the most likely deficient enzyme in this metabolic disorder?", "answer": "Galactose-1-phosphate uridyl transferase", "options": {"A": "Galactokinase", "B": "Galactose-1-phosphate uridyl transferase", "C": "Aldose reductase", "D": "UDP-galactose-4-epimerase", "E": "Glucose-6-phosphate dehydrogenase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 43-year-old man visits his physician’s office for a routine check-up. He tells his physician that he is otherwise healthy, except for persistent headaches that he gets every morning. Upon further questioning, he reveals that he has been changing glove sizes quite frequently over the past couple of years. His wedding ring doesn’t fit him anymore. He thought this was probably due to some extra weight that he has put on. Vital signs include: blood pressure 160/90 mm Hg, heart rate 82/min, and respiratory rate 21/min. His current physical appearance is cataloged in the image. His past medical history is significant for diabetes for which he has been receiving treatment for the past 2 years. Which of the following organs most likely has a structural abnormality that has resulted in this patient’s current presentation?", "answer": "Anterior pituitary gland", "options": {"A": "Anterior pituitary gland", "B": "Posterior pituitary gland", "C": "Pancreas", "D": "Liver", "E": "Lungs"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Two days after being admitted for acute myocardial infarction, a 61-year-old man has sharp, substernal chest pain that worsens with inspiration and improves when leaning forward. Cardiac examination shows a scratchy sound best heard over the left sternal border. Histopathological examination of the affected tissue is most likely to show which of the following findings?", "answer": "Neutrophilic infiltration", "options": {"A": "Neutrophilic infiltration", "B": "Normal myocardium", "C": "Coagulative necrosis", "D": "Collagenous scar tissue", "E": "Granulation tissue with macrophages"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old man comes to the physician because of a 6-week history of intermittent fever, abdominal pain, bloody diarrhea, and sensation of incomplete rectal emptying. He also has had a 4.5-kg (10-lb) weight loss over the past 3 months. Abdominal examination shows diffuse tenderness. Colonoscopy shows circumferential erythematous lesions that extend without interruption from the anal verge to the cecum. A biopsy specimen taken from the rectum shows mucosal and submucosal inflammation with crypt abscesses. This patient is most likely at risk of developing colon cancer with which of the following characteristics?", "answer": "Non-polypoid dysplasia", "options": {"A": "Unifocal lesion", "B": "Late p53 mutation", "C": "Non-polypoid dysplasia", "D": "Low-grade lesion", "E": "Early APC mutation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old boy presents to his pediatrician along with his parents due to episodes of “staring into space.” This symptom occurs several times a day and lasts only a few seconds. During these episodes, the boy does not respond to verbal or physical stimulation, and his parents deny him falling down or shaking. After the episode, the boy returns to his normal activity and is not confused. The parents deny any history of head trauma, recent medication use, or infection. Neurological exam is unremarkable. His episode is precipitated as he blows at a pinwheel. An EEG is performed, which shows 3-Hz spike and waveform. Which of the following is the best treatment option for this patient?", "answer": "Ethosuximide", "options": {"A": "Ethosuximide", "B": "Levetiracetam", "C": "Lamotrigine", "D": "Valproic acid", "E": "Zonisamide"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45 year-old gentleman presents to his primary care physician complaining of wrist pain and is diagnosed with carpal tunnel syndrome. Upon further questioning, the patient admits that he has recently been outgrowing his gloves and shoes and has had to purchase a new hat as well due to increased head size. Upon exam, he is found to have new mild hypertension and on basic labs he is found to be hyperglycemic. Which of the following is the best blood test to diagnose his suspected disorder?", "answer": "IGF-1 level", "options": {"A": "Hydroxyproline level", "B": "Alkaline Phosphatase level", "C": "Cortisol level", "D": "Growth Hormone level", "E": "IGF-1 level"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old male with a history of hypertension presents with chest pain and hoarseness. Patient reports that his hoarseness onset gradually approximately 2 weeks ago and has steadily worsened. He states that approximately 2 hours ago he had sudden onset chest pain which has not improved. The patient describes the chest pain as severe, sharp in character, localized to the midline and radiating to the back. Past medical history is significant for hypertension diagnosed 10 years previously, which was being managed medically, although patient admits he stopped taking his medication and has not been to his doctor in the last couple of years. No current medications. Patient admits to a 20-pack-year smoking history.\nVital signs are temperature 37 °C (98.6 °F), blood pressure 169/100 mm Hg, pulse 85/min, respiration rate 19/min, and oxygen saturation 98% on room air. On physical exam, patient is diaphoretic and in distress. Cardiac exam is significant for an early diastolic murmur. Lungs are clear to auscultation. Remainder of physical exam is normal. While performing the exam, the patient suddenly grips his chest and has a syncopal episode. He cannot be roused. Repeat vital signs show blood pressure 85/50 mm Hg, pulse 145/min, respiration rate 25/min, and oxygen saturation 92% on room air. Extremities are pale and cool.\nPatient is intubated. High flow supplemental oxygen and aggressive fluid resuscitation are initiated. Type and crossmatch are ordered. Which of the following is the next best step in management?", "answer": "Transthoracic echocardiography", "options": {"A": "Chest X-ray", "B": "EKG", "C": "Transthoracic echocardiography", "D": "Cardiac troponins", "E": "Emergency surgery"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old G1P0 woman at an estimated gestational age of 9 weeks presents for her first prenatal visit following a positive home pregnancy test. She says she missed 2 periods but assumed it was due to stress at work. She has decided to continue with the pregnancy. Her past medical history is significant for migraine headaches, seizures, and asthma. She takes multiple medications for her condition. Physical examination is unremarkable. An ultrasound confirms a 9-week-old intrauterine pregnancy. Which of these following medications poses the greatest risk to the fetus?", "answer": "Valproic acid", "options": {"A": "Acetaminophen", "B": "Sumatriptan", "C": "Valproic acid", "D": "Albuterol", "E": "Budesonide"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-day-old newborn is brought to the physician because of a generalized rash for 1 day. He was born at term. The mother had no prenatal care and has a history of gonorrhea, which was treated 4 years ago. The newborn is at the 50th percentile for head circumference, 60th percentile for length, and 55th percentile for weight. His temperature is 36.8°C (98.2°F), pulse is 152/min, and respirations are 51/min. Examination shows an erythematous maculopapular rash and pustules with an erythematous base over the trunk and extremities, sparing the palms and soles. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Erythema toxicum", "options": {"A": "Acropustulosis", "B": "Erythema toxicum", "C": "Milia", "D": "Pustular melanosis", "E": "Congenital syphilis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A hospitalized 45-year-old man has had mild flank pain since awakening 3 hours ago. He also reports a new generalized rash. Two weeks ago, he was diagnosed with pulmonary tuberculosis. Current medications include isoniazid, pyrazinamide, rifampin, ethambutol, and pyridoxine. His temperature is 38.3°C (100.9°F), pulse is 74/min, and blood pressure is 128/72 mm Hg. Examination of the skin shows diffuse erythema with confluent papules. There is no costovertebral angle tenderness. Laboratory studies show:\nLeukocyte count 9,800/mm3\nSegmented neutrophils 59%\nBands 3%\nEosinophils 4%\nLymphocytes 29%\nMonocytes 5%\nSerum\nUrea nitrogen 25 mg/dL\nCreatinine 1.9 mg/dL\nUrine\nWBC 8–10/hpf\nEosinophils numerous\nRBC 5–6/hpf\nRBC casts negative\nWBC casts numerous\nIn addition to intravenous fluid resuscitation, which of the following is the most appropriate next step in management?\"", "answer": "Discontinue rifampin", "options": {"A": "Initiate hemodialysis", "B": "Administer ciprofloxacin", "C": "Discontinue rifampin", "D": "Perform serum protein electrophoresis", "E": "Perform renal biopsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old woman comes to the emergency department with fever, abdominal pain, and nausea for the past 7 hours. The pain started in the right lower abdomen but has now progressed to diffuse abdominal pain. Her temperature is 39.5°C (103.1°F). Physical examination shows generalized abdominal tenderness with rebound, guarding, and decreased bowel sounds. She is taken for an emergency exploratory laparoscopy, which shows a perforated appendix with an adjacent abscess and peritoneal inflammation. Cultures from the abscess fluid grow catalase-producing, anaerobic, gram-negative rods that have the ability to grow in bile. Which of the following is the most appropriate pharmacotherapy for this patient?", "answer": "Ampicillin and sulbactam", "options": {"A": "Vancomycin and azithromycin", "B": "Piperacillin", "C": "Cefazolin and doxycycline", "D": "Ampicillin and sulbactam", "E": "Aztreonam"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old male presents to his primary care physician for evaluation of fever and an unintended weight loss of 25 pounds over the last 4 months. He also has decreased appetite and complains of abdominal pain located in the right upper quadrant. The patient has not noticed any changes in stool or urine. He emigrated from Malaysia to the United States one year prior. Social history reveals that he smokes half a pack per day and has 5-7 drinks of alcohol per day. The patient is up to date on all of his vaccinations. Physical exam findings include mild jaundice as well as an enlarged liver edge that is tender to palpation. Based on clinical suspicion, biomarker labs are sent and show polycythemia and an elevated alpha fetoprotein level but a normal CA 19-9 level. Surface antigen for hepatitis B is negative. Ultrasound reveals a normal sized gallbladder. Given this presentation, which of the following organisms was most likely associated with the development of disease in this patient?", "answer": "Acute angle branching fungus", "options": {"A": "Acute angle branching fungus", "B": "Curved gram-negative bacteria", "C": "Enveloped DNA virus", "D": "Naked DNA virus", "E": "Trematode from undercooked fish"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old man is brought to the emergency department 30 minutes after being involved in a high-speed motor vehicle collision in which he was a restrained driver. On arrival, he is alert and oriented. His pulse is 112/min, respirations are 29/min, and blood pressure is 100/60 mm Hg. The pupils are equal and reactive to light. There is a 3-cm laceration over the forehead and multiple bruises over the trunk. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft and nontender. The right knee is swollen and tender; range of motion is limited by pain. Infusion of 0.9% saline is begun and intravenous acetaminophen is administered. Two hours later, blood-tinged fluid spontaneously drains from both nostrils, and is made worse by leaning forward. On a piece of gauze, it shows up as a rapidly-expanding clear ring of fluid surrounding blood. Further evaluation of this patient is most likely to show which of the following?", "answer": "Bilateral periorbital ecchymosis", "options": {"A": "Cranial nerve XII palsy", "B": "Bilateral periorbital ecchymosis", "C": "Numbness of upper cheek area", "D": "Carotid artery dissection", "E": "Retroauricular ecchymosis\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old man comes to the physician after receiving a high blood pressure reading of 160/90 mm Hg at an annual employee health check-up. During the past few months, the patient has had occasional headaches and mild abdominal pain, both of which were relieved with ibuprofen. He has also had several episodes of heart palpitations. He has no history of serious illness. His mother and father both have hypertension. He has smoked one pack of cigarettes daily for the past 10 years and drinks one glass of wine daily. He occasionally smokes marijuana. He appears pale. His temperature is 36.8°C (98.2°F), pulse is 103/min, and blood pressure is 164/102 mm Hg. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 15.3 g/dL\nLeukocyte count 7,900/mm3\nPlatelet count 223,000/mm3\nSerum\nNa+ 138 mEq/L\nK+ 4.6 mEq/L\nCl- 103 mEq/L\nUrea nitrogen 14 mg/dL\nGlucose 90 mg/dL\nCreatinine 0.9 mg/dL\nPlasma metanephrines 1.2 nmol/L (N < 0.5 nmol/L)\nUrine toxicology screening is positive for tetrahydrocannabinol (THC). Renal doppler shows no abnormalities. A CT scan of the abdomen shows a mass in the left adrenal gland. Which of the following is the most appropriate next step in management of this patient?\"", "answer": "Phenoxybenzamine", "options": {"A": "MIBG therapy", "B": "Phenoxybenzamine", "C": "Resection of adrenal mass", "D": "Propranolol", "E": "Metoprolol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old man is brought to the emergency department 40 minutes after spilling hot oil over himself in a kitchen accident. Examination shows multiple tense blisters over the abdomen, anterior chest, and anterior and posterior aspects of the right upper extremity and right thigh. On deroofing the blisters, the skin underneath is tender, mottled, and does not blanch with pressure. The skin over the left thigh is tender, erythematous, and shows quick capillary refill after blanching with pressure. Which of the following most closely approximates the body surface area affected by 2nd-degree burns in this patient?", "answer": "36%", "options": {"A": "9%", "B": "18%", "C": "45%", "D": "54%", "E": "36%"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old man is brought to the emergency department by his girlfriend because of increasing confusion for the past 6 hours. He drinks large amounts of alcohol daily and occasionally uses illicit drugs. He is lethargic and oriented only to person. Physical examination shows jaundice, hepatomegaly, and scattered petechiae over the trunk and back. Neurologic examination shows normal, reactive pupils and a flapping tremor when the wrists are extended. A drug with which of the following mechanism of action would be most appropriate for this patient's condition?", "answer": "Excretion of NH4", "options": {"A": "Inhibition of D2 receptors", "B": "Excretion of NH4", "C": "Excretion of free iron", "D": "Activation of GABA receptors", "E": "Production of NH3"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old homeless male presents to the ED because he hasn’t felt well recently. He states that he has been feeling nauseous and extremely weak over the past few days. He has several previous admissions for alcohol intoxication and uses heroin occasionally. His temperature is 100.9°F (38.3°C), blood pressure is 127/89 mmHg, and pulse is 101/min. His physical examination is notable for palmar erythema, tender hepatomegaly, and gynecomastia. His laboratory findings are notable for:\n\nAST: 170 U/L\nALT: 60 U/L\nGGT: 400 (normal range: 0-45 U/L)\nAlkaline phosphatase: 150 IU/L\nDirect bilirubin: 0.2 mg/dL\nTotal bilirubin: 0.8 mg/dL\nWBC: 10,500\nSerum iron: 100 µg/dL\nTIBC: 300 µg/dL (normal range: 250–370 µg/dL)\nSerum acetaminophen screen: Negative\nSerum AFP: 6 ng/mL (normal range: < 10ng/mL)\n\nWhich of the following is the most likely cause of this patient’s symptoms?", "answer": "Alcoholic hepatitis", "options": {"A": "Acute cholangitis", "B": "Hepatocellular carcinoma", "C": "Alcoholic hepatitis", "D": "Acute viral hepatitis", "E": "Hereditary hemochromatosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old woman presents to your office for a gynecological exam. She says that she has been in good health and has no complaints. She has been in a steady monogamous relationship for the past year. Physical examination was unremarkable. Screening tests are performed and return positive for gonorrhea. You treat her with an intramuscular injection of ceftriaxone and 7 day course of doxycycline. What else is recommended for this case?", "answer": "Treat her partner for gonorrhea and chlamydia", "options": {"A": "Treatment with penicillin G for potential co-infection with syphilis", "B": "Treat her partner for gonorrhea and chlamydia", "C": "Recheck her in 1 week for gonorrhea and chlamydia", "D": "Inform her that her partner is likely cheating on her", "E": "Perform an abdominal ultrasonography in order to rule out pelvic inflammatory disease"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 63-year-old man with high blood pressure, dyslipidemia, and diabetes presents to the clinic for routine follow-up. He has no current complaints and has been compliant with his chronic medications. His blood pressure is 132/87 mm Hg and his pulse is 75/min and regular. On physical examination, you notice that he has xanthelasmas on both of his eyelids. He currently uses a statin to lower his LDL but has not reached the LDL goal you have set for him. You would like to add an additional medication for LDL control. Of the following, which statement regarding fibrates is true?", "answer": "Fibrates can potentiate the risk of myositis when given with statins", "options": {"A": "The primary effect of fibrates is to lower LDL", "B": "Fibrates can cause significant skin flushing and pruritus", "C": "Fibrates can potentiate the risk of myositis when given with statins", "D": "Fibrates can increase the risk of cataracts", "E": "Fibrates inhibit the rate-limiting step in cholesterol synthesis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 61-year-old woman comes to the physician for a follow-up examination 1 week after undergoing right-sided radical mastectomy and axillary lymph node dissection for breast cancer. She says that she has been unable to comb her hair with her right hand since the surgery. Physical examination shows shoulder asymmetry. She is unable to abduct her right arm above 90 degrees. When she pushes against a wall, there is protrusion of the medial aspect of the right scapula. Injury to which of the following nerves is the most likely cause of this patient's condition?", "answer": "Long thoracic nerve", "options": {"A": "Upper trunk of the brachial plexus", "B": "Axillary nerve", "C": "Long thoracic nerve", "D": "Suprascapular nerve", "E": "Thoracodorsal nerve"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old woman comes to the physician because of intermittent heaviness and paresthesia of the right arm for the past 2 months. She has also had multiple episodes of lightheadedness while painting a mural for the past 2 weeks. During these episodes, she was nauseated and had blurred vision. Her symptoms resolved after she drank some juice. She has hypertension, type 2 diabetes mellitus, and hypercholesterolemia. Current medications include metformin, glipizide, enalapril, and atorvastatin. She appears anxious. Examination shows decreased radial and brachial pulses on the right upper extremity. The skin over the right upper extremity is cooler than the left. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Reversed blood flow in the right vertebral artery", "options": {"A": "Adverse effect of medications", "B": "Reversed blood flow in the right vertebral artery", "C": "Non-enzymatic glycosylation of peripheral nerve", "D": "Compression of neurovascular structures in the neck", "E": "Infarction of the middle cerebral artery"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 31-year-old physician notices that her senior colleague has been arriving late for work for the past 2 weeks. The colleague recently lost his wife to cancer and has been taking care of his 4 young children. Following the death of his wife, the department chair offered him extended time off, but he declined. Resident physicians have noted and discussed some recent changes in this colleague, such as missed clinic appointments, 2 intra-operative errors, and the smell of alcohol on his breath on 3 different occasions. Which of the following is the most appropriate action by the physician regarding her colleague?", "answer": "Inform the local Physician Health Program", "options": {"A": "Advise resident physicians to report future misconduct to the department chair", "B": "Alert the State Licensing Board", "C": "Confront the colleague in private", "D": "Contact the colleague's friends and family", "E": "Inform the local Physician Health Program"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old woman comes to the physician because of a 10-month history of joint pain and stiffness in her wrists and fingers. The symptoms are worse in the morning and improve with activity. Physical examination shows swelling and warmth over the MCP and wrist joints in both hands. An x-ray of the hands is shown. Synovial biopsy from an affected joint would most likely show which of the following?", "answer": "Proliferation of granulation tissue", "options": {"A": "Noninflammatory superficial fibrin deposits", "B": "Monosodium urate crystals", "C": "Calcium pyrophosphate crystals", "D": "Noncaseating granulomas", "E": "Proliferation of granulation tissue"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old female presents to your office due to one week of “feeling unwell.” She complains of a headache and non-productive cough over the last several days, which have both worsened today. She does not have any history of serious infection and is not currently taking any medication. On physical exam, her temperature is 99°F (37.2°C), blood pressure is 120/78 mmHg, pulse is 90/min, respirations are 21/min, and pulse oximetry is 98% on room air. She has diffuse rhonchi bilaterally. You decide to order a chest radiograph, shown in image A. The pathogen responsible for her current presentation most likely belongs to which of the following categories?", "answer": "Non-gram staining bacteria", "options": {"A": "Gram-positive organism", "B": "Gram-negative organism", "C": "Non-gram staining bacteria", "D": "DNA virus", "E": "RNA virus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 61-year-old man comes to the physician because of several episodes of dark urine over the past 2 weeks. He does not have dysuria or flank pain. He works in a factory that produces dyes. Since an accident at work 5 years ago, he has had moderate hearing loss bilaterally. He takes no medications. He has smoked a pack of cigarettes daily for 29 years and drinks one alcoholic beverage daily. Vital signs are within normal limits. Physical examination shows no abnormalities. His urine is pink; urinalysis shows 80 RBC/hpf but no WBCs. Cystoscopy shows a 3-cm mass in the bladder mucosa. The mass is resected. Pathologic examination shows an urothelial carcinoma with penetration into the muscular layer. An x-ray of the chest and a CT scan of the abdomen and pelvis with contrast show a normal upper urinary tract and normal lymph nodes. Which of the following is the most appropriate next step in management?", "answer": "Radical cystectomy", "options": {"A": "Transurethral resection of tumor with intravesical chemotherapy", "B": "Radiation therapy", "C": "Transurethral resection of tumor with intravesical BCG instillation", "D": "Radical cystectomy", "E": "Palliative polychemotherapy\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year-old boy is brought to the physician by his parents because of fever for 3 days. During the period, he has had fatigue, severe burning with urination, and increased urination. The mother reports that his urine has red streaks and a “strange” odor. He has taken acetaminophen twice a day for the past two days with no improvement in his symptoms. He has had multiple ear infections in the past but has been healthy in the past year. His immunizations are up-to-date. He appears uncomfortable. His temperature is 39°C (102.2°F). Examination shows right-sided costovertebral angle tenderness. Laboratory studies show a leukocyte count of 16,000/cm3 and an erythrocyte sedimentation rate of 40 mm/hr. Urine dipstick shows leukocyte esterase and nitrites. Urinalysis shows:\nBlood 2+\nProtein 2+\nWBC 24/hpf\nRBC 50/hpf\nRBC casts none\nWBC casts numerous\nGranular casts none\nUrine cultures are sent to the laboratory. Damage to which of the following structures is the most likely cause of this patient's hematuria?\"", "answer": "Renal papilla", "options": {"A": "Renal tubules", "B": "Renal papilla", "C": "Urethral epithelium", "D": "Renal interstitium", "E": "Mucosa of the bladder\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old woman presents to her primary care physician for a concern about her pregnancy. This is her first pregnancy, and she is currently at 33 weeks gestation. She states that she has experienced diffuse swelling of her ankles and legs and is concerned that it is abnormal. Otherwise, she has no concerns. The patient has a past medical history of obesity and diabetes. Her temperature is 98.5°F (36.9°C), blood pressure is 147/92 mmHg, pulse is 80/min, respirations are 15/min, and oxygen saturation is 97% on room air. Physical exam reveals bilateral edema of the lower extremities. Which of the following is the best next step in management?", "answer": "Spot protein to creatinine ratio", "options": {"A": "A 24 hour urine protein", "B": "Echocardiography", "C": "Reassurance and followup in 1 week", "D": "Spot protein to creatinine ratio", "E": "Urinalysis and urine protein"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old woman is brought to the emergency department with fever, myalgia, and cough for 3 days. She lives in an assisted living facility and several of her neighbors have had similar symptoms. She has hypertension treated with lisinopril. She has not been vaccinated against influenza. Her temperature is 38.9°C (102.2°F), pulse is 105/min, respirations are 22/min, and blood pressure is 112/62 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 89%. Her leukocyte count is 10,500/mm3, serum creatinine is 0.9 mg/dL, and serum procalcitonin level is 0.05 μg/L (N < 0.06). An x-ray of the chest shows reticulonodular opacities in the lower lobes bilaterally. Blood and sputum cultures are negative. The patient is admitted to the hospital and empirical treatment with ceftriaxone and azithromycin is begun. Two days after admission, her temperature is 37.6°C (99.7°F) and pulse oximetry shows an oxygen saturation of 96% on room air. Her serum procalcitonin level is 0.04 μg/L. Which of the following is the most appropriate next step in management?", "answer": "Discontinue ceftriaxone and azithromycin", "options": {"A": "Start treatment with oseltamivir", "B": "Discontinue ceftriaxone and azithromycin", "C": "Discontinue ceftriaxone and continue azithromycin to complete 7-day course", "D": "Repeat sputum culture", "E": "Repeat x-ray of the chest\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old male presents presents for a new patient visit. He states that he is in good health but has had decreasing exercise tolerance and increased levels of shortness of breath over the past 5 years. He believed that it was due to aging; he has not seen a doctor in 10 years. On auscultation, you note an early diastolic decrescendo blowing murmur that radiates along the left sternal border. In the United States, what is the most likely cause of this patient's condition?", "answer": "Congenital bicuspid aortic valve", "options": {"A": "Rheumatic heart disease", "B": "Syphilis", "C": "Connective tissue disease", "D": "Myxomatous degeneration", "E": "Congenital bicuspid aortic valve"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old woman presents to the emergency department with several episodes in which she felt \"dizzy.\" She has had these symptoms on and off for the past year and can recall no clear exacerbating factor or time of day when her symptoms occur. She has a perpetual sensation of fullness in her ear but otherwise has no symptoms currently. Her temperature is 97.6°F (36.4°C), blood pressure is 122/77 mmHg, pulse is 85/min, respirations are 13/min, and oxygen saturation is 98% on room air. Cardiopulmonary exam is unremarkable. The patient's gait is stable. Which of the following is also likely to be found in this patient?", "answer": "Sensorineural hearing loss", "options": {"A": "Conductive hearing loss", "B": "Gradually improving symptoms", "C": "Positional vertigo", "D": "Sensorineural hearing loss", "E": "Vertical nystagmus"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 3-year-old recent immigrant is diagnosed with primary tuberculosis. Her body produces T cells that do not have IL-12 receptors on their surface, and she is noted to have impaired development of Th1 T-helper cells. Which of the following cytokines would benefit this patient?", "answer": "Interferon-gamma", "options": {"A": "IL-4", "B": "IL-17", "C": "IL-22", "D": "Interferon-gamma", "E": "TGF-beta"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old woman presents to the emergency department with weakness. She states that at the end of the day she feels so fatigued and weak that she can hardly care for herself. She currently feels this way. The patient has had multiple illnesses recently and has been traveling, hiking, and camping. Her temperature is 98.0°F (36.7°C), blood pressure is 124/84 mmHg, pulse is 82/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam is notable for 2/5 strength of the upper extremities and 4/5 strength of the lower extremities. Visual exam is notable for mild diplopia. Which of the following is the most likely diagnosis?", "answer": "Myasthenia gravis", "options": {"A": "Amyotrophic lateral sclerosis", "B": "Guillain-Barre syndrome", "C": "Lambert-Eaton syndrome", "D": "Myasthenia gravis", "E": "Tick paralysis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old patient with no significant past medical history arrives to the ED with abdominal cramps, nausea, and vomiting. He has had no recent travel or chemical exposures; however, three other members of his family also arrived concurrently to the ED with abdominal cramps, nausea, and vomiting. When asked about their recent activities, they recall that they had shared a lunch of leftover fried rice and soft boiled eggs about 5 hours earlier. The patients are otherwise afebrile and deny any history of diarrhea. Which of the following toxins is the most likely to have caused these symptoms?", "answer": "Cereulide", "options": {"A": "Exotoxin A", "B": "Cereulide", "C": "Toxin B", "D": "Shiga toxin", "E": "Endotoxin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Please refer to the summary above to answer this question\nWhich of the following is the most likely diagnosis?\"\n\"Patient Information\nAge: 66 years\nGender: M, self-identified\nEthnicity: African-American\nSite of Care: office\nHistory\nReason for Visit/Chief Concern: “I need to go to the bathroom all the time.”\nHistory of Present Illness:\n1-year history of frequent urination\nurinates every 2–3 hours during the day and wakes up at least 3 times at night to urinate\nhas had 2 episodes of cystitis treated with antibiotics in the past 4 months\nhas a weak urinary stream\nhas not noticed any blood in the urine\ndoes not have any pain with urination or ejaculatory dysfunction\nPast Medical History:\ntype 2 diabetes mellitus\nnephrolithiasis, treated with percutaneous nephrolithotomy\nessential tremor\nMedications:\nmetformin, canagliflozin, propranolol\nAllergies:\nsulfa drugs\nSocial History:\nsexually active with his wife; does not use condoms consistently\nhas smoked one pack of cigarettes daily for 50 years\ndrinks one to two glasses of beer weekly\nPhysical Examination\nTemp Pulse Resp BP O2 Sat Ht Wt BMI\n37°C\n(98.6°F)\n72/min 16/min 134/81 mm Hg –\n183 cm\n(6 ft)\n105 kg\n(231 lb)\n31 kg/m2\nAppearance: no acute distress\nPulmonary: clear to auscultation\nCardiac: regular rate and rhythm; normal S1, S2; S4 gallop\nAbdominal: overweight; no tenderness, guarding, masses, bruits, or hepatosplenomegaly\nExtremities: no joint erythema, edema, or warmth; dorsalis pedis, radial, and femoral pulses intact\nGenitourinary: no lesions or discharge\nRectal: slightly enlarged, smooth, nontender prostate\nNeurologic: alert and oriented; cranial nerves grossly intact; no focal neurologic deficits\"", "answer": "Benign prostatic hyperplasia", "options": {"A": "Neurogenic bladder", "B": "Acute prostatitis", "C": "Prostate cancer", "D": "Urethral stricture", "E": "Benign prostatic hyperplasia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old G2P2 female gives birth to a healthy baby boy at 39 weeks of gestation via vaginal delivery. Immediately after the delivery of the placenta, she experiences profuse vaginal hemorrhage. Her prior birthing history is notable for an emergency cesarean section during her first pregnancy. She did not receive any prenatal care during either pregnancy. Her past medical history is notable for obesity and diabetes mellitus, which is well controlled on metformin. Her temperature is 99.0°F (37.2°C), blood pressure is 95/50 mmHg, pulse is 125/min, and respirations are 22/min. On physical examination, the patient is in moderate distress. Her extremities are pale, cool, and clammy. Capillary refill is delayed. Which of the following is the most likely cause of this patient’s bleeding?", "answer": "Chorionic villi attaching to the myometrium", "options": {"A": "Chorionic villi attaching to the decidua basalis", "B": "Chorionic villi attaching to the myometrium", "C": "Chorionic villi invading into the myometrium", "D": "Chorionic villi invading into the serosa", "E": "Placental implantation over internal cervical os"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman is started on a new experimental intravenous drug X. In order to make sure that she is able to take this drug safely, the physician in charge of her care calculates the appropriate doses to give to this patient. Data on the properties of drug X from a subject with a similar body composition to the patient is provided below:\n\nWeight: 100 kg\nDose provided: 1500 mg\nSerum concentration 15 mg/dL\nBioavailability: 1\n\nIf the patient has a weight of 60 kg and the target serum concentration is 10 mg/dL, which of the following best represents the loading dose of drug X that should be given to this patient?", "answer": "600 mg", "options": {"A": "150 mg", "B": "300mg", "C": "450 mg", "D": "600 mg", "E": "1000 mg"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old Caucasian boy is brought by his mother to the pediatrician with a red and swollen elbow. He was playing outside a few days prior to presentation when he fell and lightly scraped his elbow on the sidewalk. He was born at 34 weeks’ gestation and was in the neonatal ICU for 2 days. He has a history of easy bruising and bleeding gums. His temperature is 102.1°F (38.9°C), blood pressure is 105/65 mmHg, pulse is 110/min, and respirations are 20/min. On exam, he has a swollen, erythematous, fluctuant, and exquisitely tender mass on his right elbow. There is expressible purulence coming from his wound. A peripheral blood smear in this patient would most likely reveal which of the following findings?", "answer": "Neutrophils with abundant peroxidase-positive granules", "options": {"A": "Absence of dark blue cytoplasmic staining upon nitroblue tetrazolium administration", "B": "Macrocytic erythrocytes and acanthocytes", "C": "Neutrophils with abundant peroxidase-positive granules", "D": "Neutrophils with peroxidase-negative granules", "E": "Neutrophils with pale cytoplasm without granules"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 16-year-old boy is brought to the physician because of a lesion that has been growing on his jaw over the past several months. He recently immigrated to the USA from Kenya with his family. Physical examination shows a 3-cm solid mass located above the left mandible. There is cervical lymphadenopathy. Biopsy of the mass shows sheets of lymphocytes and interspersed reactive histiocytes with abundant, clear cytoplasm and phagocytosed debris. Which of the following mechanisms is most likely directly responsible for the malignant transformation of this patient's cells?", "answer": "Activation of transcription", "options": {"A": "Activation of transcription", "B": "Defect in DNA repair", "C": "Impairment of receptor function", "D": "Inhibition of cell cycle arrest", "E": "Integration of viral DNA\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A scientist is studying the mechanism by which the gastrointestinal system coordinates the process of food digestion. Specifically, she is interested in how distension of the lower esophagus by a bolus of food changes responses in the downstream segments of the digestive system. She observes that there is a resulting relaxation and opening of the lower esophageal (cardiac) sphincter after the introduction of a food bolus. She also observes a simultaneous relaxation of the orad stomach during this time. Which of the following substances is most likely involved in the process being observed here?", "answer": "Vasoactive intestinal polypeptide", "options": {"A": "Ghrelin", "B": "Motilin", "C": "Neuropeptide-Y", "D": "Secretin", "E": "Vasoactive intestinal polypeptide"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 18-year-old male is seen for a routine physical prior to starting college. He will be moving from Ohio to California, away from his family for the first time. His temperature is 36.8 deg C (98.2 deg F), pulse is 74/min, and blood pressure is 122/68 mmHg. BMI is 24. On questioning, he reveals that he has a habit of binge eating during times of stress, particularly during exams. He then feels guilty about his behavior and attempts to compensate by going to the gym, sometimes for 4+ hours per day. He is disturbed by this behavior and feels out of control. He denies ever vomiting as a means of loosing weight. What is the most likely diagnosis?", "answer": "Bulimia nervosa", "options": {"A": "Anorexia nervosa", "B": "Bulimia nervosa", "C": "Normal behavior variant", "D": "Hypomania", "E": "Body dysmorphic disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-year-old boy is brought to the physician because of a progressive headache and neck pain for 2 weeks. During this period, he has had multiple episodes of dizziness and tingling sensations in his arms and hands. A year ago, he underwent closed reduction of a dislocated shoulder that he suffered after a fall. He underwent surgical removal of a sac-like protuberance on his lower back, soon after being born. His temperature is 36.7°C (98°F), pulse is 80/min, and blood pressure is 100/80 mm Hg. His neck is supple. Neurological examination shows sensorineural hearing loss bilaterally and normal gross motor function. Fundoscopy reveals bilateral optic disk swelling. An MRI of the brain is shown. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Chiari II malformation", "options": {"A": "Medulloblastoma", "B": "Intraventricular hemorrhage", "C": "Chiari II malformation", "D": "Vestibular schwannoma", "E": "Brachial plexus injury"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 16-year-old boy is brought to the physician by his host parents for evaluation of a progressively pruritic rash over his shoulders and buttocks for the past 6 months. He recently came to the United States from Nigeria to attend a year of high school. He reports that it has been increasingly difficult for him to read the whiteboard during classes. Physical examination shows symmetrically distributed papules 4–8 mm in diameter, excoriation marks, and patchy hyperpigmentation over his shoulders, waist, and buttocks. There is nontender inguinal lymphadenopathy and several firm, nontender subcutaneous nodules along the right iliac crest. Six skin snip biopsies are taken from the pelvic girdle, buttocks, and thigh, and are then incubated in saline. After 24 hours, microscopic examination shows motile microfilariae. Which of the following is the most likely diagnosis?", "answer": "Onchocerciasis", "options": {"A": "Lymphatic filariasis", "B": "Onchocerciasis", "C": "Trichuriasis", "D": "Cysticercosis", "E": "Cutaneous larva migrans"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A study is designed to assess the functions of immune components. The investigator obtains a lymph node biopsy from a healthy subject and observes it under a microscope. A photomicrograph of the cross-section of this lymph node is shown. Which of the following immunologic processes most likely occurs in the region labeled with an arrow?", "answer": "Isotype switching", "options": {"A": "T cell activation", "B": "Macrophage activation", "C": "Negative selection", "D": "V(D)J recombination", "E": "Isotype switching"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old man presents to the physician with complaints of fever with rigors, headache, malaise, muscle pains, nausea, vomiting, and decreased appetite for the past 3 days. He informs the physician that he had been backpacking on the Appalachian Trail in the woods of Georgia in the month of June, 2 weeks ago, and had been bitten by a tick there. His temperature is 39.0°C (102.3°F), pulse is 94/min, respirations are 18/min, and blood pressure is 126/82 mm Hg. His physical exam does not reveal any significant abnormality except for mild splenomegaly. Laboratory studies show:\nTotal white blood cell count 3,700/mm3 (3.7 x 109/L)\nDifferential count  \nNeutrophils 85%\nLymphocytes 12%\nMonocytes 2%\nEosinophils 1%\nBasophils 0%\nPlatelet count 88,000/mm3 (95 x 109/L)\nSerum alanine aminotransferase 140 IU/L\nSerum aspartate aminotransferase 80 IU/L\nMicroscopic examination of a peripheral blood smear stained with Wright-Giemsa stain shows the presence of morulae in the cytoplasm of leukocytes. In addition to drugs for symptomatic relief, what is the most appropriate initial step in the treatment of this patient?", "answer": "Doxycycline", "options": {"A": "Daptomycin", "B": "Ceftriaxone", "C": "Doxycycline", "D": "Ciprofloxacin", "E": "Rifampin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old woman is brought to the emergency department by her son after he noticed that she was slurring her speech. He also noticed that she appeared to have difficulty using her fork about halfway through dinner when the speech problems started. He brought her to the emergency department immediately and he estimates that only 1 hour has passed since the beginning of the symptoms. An immediate exam is conducted. A medication is administered to ameliorate the effects of this patient's condition that would not be available for use if the patient had presented significantly later. An hour later the patient's condition becomes significantly worse and new deficits are found. Which of the following agents should be used at this point?", "answer": "Aminocaproic acid", "options": {"A": "Aminocaproic acid", "B": "Antivenin", "C": "Plasma transfusion", "D": "Protamine sulfate", "E": "Vitamin K"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 10-year-old boy is brought to the pediatric clinic because of persistent sinus infections. For the past 5 years, he has had multiple sinus and upper respiratory infections. He has also had recurrent diarrhea throughout childhood. His temperature is 37.0°C (98.6°F), the heart rate is 90/min, the respirations are 16/min, and the blood pressure is 125/75 mm Hg. Laboratory studies show abnormally low levels of one immunoglobulin isotype but normal levels of others. Which of the following is the most likely diagnosis?", "answer": "Selective IgA deficiency", "options": {"A": "Chediak-Higashi syndrome", "B": "Common variable immunodeficiency", "C": "Drug-induced IgA deficiency", "D": "Selective IgA deficiency", "E": "Transient hypogammaglobulinemia of infancy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old male presents to the physician with a 9-year history of recurring acne on his face. He has tried a number of over-the-counter face wash, gels, and supplements over the past few years with temporary relief but no significant lasting effects. The acne has gotten worse over time and now he is especially concerned about his appearance. A physical examination reveals numerous nodulocystic lesions over the face and neck. Scarring is present interspersed between the pustules. There are some lesions on the shoulders and upper back as well. Which of the following is the most appropriate treatment option for this patient at this time?", "answer": "Oral isotretinoin", "options": {"A": "Oral erythromycin", "B": "Oral doxycycline", "C": "Oral isotretinoin", "D": "Topical isotretinoin", "E": "Topical salicylic acid"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old man presents with shortness of breath and right-sided chest pain. Physical exam reveals decreased breath sounds and dull percussion at the right lung base. Chest X-ray reveals a right-sided pleural effusion. A thoracentesis was performed, removing 450 mL of light pink fluid. Pleural fluid analysis reveals:\nPleural fluid to serum protein ratio: 0.35\nPleural fluid to serum LDH ratio: 0.49 \nLactate dehydrogenase (LDH): 105 IU (serum LDH Reference: 100–190)\nWhich of the following disorders is most likely in this patient?", "answer": "Congestive heart failure", "options": {"A": "Pancreatitis", "B": "Chylothorax", "C": "Uremia", "D": "Sarcoidosis", "E": "Congestive heart failure"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 63-year-old man presents to the clinic with fever accompanied by shortness of breath. The symptoms developed a week ago and have been progressively worsening over the last 2 days. He reports his cough is productive of thick, yellow sputum. He was diagnosed with chronic obstructive pulmonary disease 3 years ago and has been on treatment ever since. He quit smoking 10 years ago but occasionally experiences shortness of breath along with chest tightness that improves with the use of an inhaler. However, this time the symptoms seem to be more severe and unrelenting. His temperature is 38.6°C (101.4°F), the respirations are 21/min, the blood pressure is 100/60 mm Hg, and the pulse is 105/min. Auscultation reveals bilateral crackles and expiratory wheezes. His oxygen saturation is 95% on room air. According to this patient’s history, which of the following should be the next step in the management of this patient?", "answer": "Chest X-ray", "options": {"A": "Chest X-ray", "B": "CT scan", "C": "Bronchoscopy", "D": "Arterial blood gases", "E": "Bronchoprovocation test"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old white man comes to the physician because of increasing generalized fatigue for 6 months. He has been unable to work out at the gym during this period. He has also had cramping lower abdominal pain and diarrhea for the past 5 weeks that is occasionally bloody. His father was diagnosed with colon cancer at the age of 65. He has smoked half a pack of cigarettes daily for the past 10 years. He drinks 1–2 beers on social occasions. His temperature is 37.3°C (99.1°F), pulse is 88/min, and blood pressure is 116/74 mm Hg. Physical examination shows dry mucous membranes. The abdomen is soft and nondistended with slight tenderness to palpation over the lower quadrants bilaterally. Rectal examination shows stool mixed with blood. His hemoglobin concentration is 13.5 g/dL, leukocyte count is 7,500/mm3, and platelet count is 480,000/mm3. Urinalysis is within normal limits. Which of the following is the most appropriate next step in management?", "answer": "Colonoscopy", "options": {"A": "Colonoscopy", "B": "Flexible sigmoidoscopy", "C": "D-xylose absorption test", "D": "CT scan of the abdomen and pelvis with contrast", "E": "Capsule endoscopy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old presents to the clinic with a 3-day history of severe mid-epigastric abdominal pain radiating to the back. The patient has hypertension, diabetes mellitus, and hypertriglyceridemia. Prescription medications include enalapril, metformin, sitagliptin, glargine, lispro, and fenofibrate. The patient has not had a cigarette in more than 35 years, and reports only having 1 or 2 drinks during special occasions such as weddings and family reunions. The blood pressure is 146/90 mm Hg, the heart rate is 88/min, the respiratory rate is 10/min, and the temperature is 37.8°C (100.0°F). On physical examination, the patient appears uncomfortable but alert. The visualization of the sclera is negative for jaundice. The neck is supple and non-tender without nodules. There are no heart murmurs. The lungs are clear to auscultation bilaterally. The palpation of the abdomen elicits pain in the epigastric region. The liver is palpable along the costal margin, and the Murphy’s sign is negative. The laboratory results are as follows:\nNa+ 138 mEq/L\nK+ 4.2 mEq/L\nCl- 108 mmol/L\nHCO-3 20 mmol/L\nBUN 178 mg/dL\nCr 1.0 mg/dL\nGlucose  154 mg/dL\nLDL 117 mg/dL\nHDL 48 mg/dL\nTG 942 mg/dL\nAST 45 IU/L\nALT 48 IU/L\nGGT 27 IU/L\nAmylase  110 U/L\nLipase 250 U/L\nAccording to the clinical vignette, which of the following is the most likely diagnosis of the patient?", "answer": "Acute pancreatitis", "options": {"A": "Mallory-Weiss tear", "B": "Duodenal ulcer", "C": "Superior mesenteric artery embolism", "D": "Acute pancreatitis", "E": "Abdominal aortic aneurysm"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying the effects of an antihypertensive drug during pregnancy. Follow-up studies show that the drug can adversely affect differentiation of the ureteric bud into its direct derivatives in fetuses exposed during the first trimester. Which of the following structures is most likely to develop incorrectly in the affected fetus?", "answer": "Collecting ducts", "options": {"A": "Distal convoluted tubule", "B": "Collecting ducts", "C": "Bladder", "D": "Loop of Henle", "E": "Proximal convoluted tubule"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old woman presents to the ER with 12 hours of right colic pain that travels from her groin down her inner thigh. The patient complains of dysuria, hematuria, and reports of “passing gravel” when urinating. She was diagnosed with gout and hypertension 5 years ago. Physical examination is unremarkable. The emergency department team orders urinalysis and a CT scan that shows a mild dilation of the right ureter associated with multiple small stones of low Hounsfield unit values (HU). Which of the following findings is most likely to appear in the urinalysis of this patient?", "answer": "Acidic urine", "options": {"A": "Low specific gravity", "B": "Alkaline urine", "C": "Positive leukocyte esterase", "D": "Nitrites", "E": "Acidic urine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A new mother expresses her concerns because her 1-day-old newborn has been having feeding difficulties. The child vomits after every feeding and has had a continuous cough since shortly after birth. The mother denies any greenish coloration of the vomit and says that it is only composed of whitish milk that the baby just had. The child exhibits these coughing spells during the exam, at which time the physician notices the child’s skin becoming cyanotic. The mother states that the child was born vaginally with no complications, although her records show that she had polyhydramnios during her last ultrasound before the delivery. Which of the following is the most likely cause of the patient’s symptoms?", "answer": "Defective formation of the esophagus with gastric connection to the trachea", "options": {"A": "Obstruction due to failure of rotation of pancreatic tissue", "B": "Hypertrophy of the pyloric sphincter", "C": "Failure of neural crest cells to migrate into the myenteric plexus", "D": "Failure of recanalization of duodenum", "E": "Defective formation of the esophagus with gastric connection to the trachea"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 18-year-old man comes to the physician with his parents for a routine health maintenance examination. He noticed a swelling on his back 7 months ago. He has a history of using intravenous heroin but has not used illicit drugs for the past 2 months. There is no personal or family history of serious illness. Vital signs are within normal limits. Examination shows a 2-cm soft, lobulated, mobile swelling on the right side of his upper back. The mass slips away from the fingers when its edges are palpated. Healed track marks are present in the bilateral cubital fossae. The patient is told that the mass on his back is most likely a lipoma, a benign mass consisting of fat tissue that does not require any further treatment. He is aware of the diagnosis and informs you that he wants it removed for cosmetic reasons. Four months ago, he had asked another physician to remove it but the physician refused to perform the procedure since he did not consider it necessary. The patient is counseled regarding the potential benefits and risks of the excision and that there is a chance of recurrence. His parents ask the physician not to perform the excision. However, the patient insists on undergoing the procedure. Which of the following is the most appropriate next step in management?", "answer": "Perform the excision", "options": {"A": "Ask the patient to follow up in 6 months", "B": "Perform the excision", "C": "Refer to the hospital ethics committee", "D": "Refer him to a methadone clinic", "E": "Request parental consent\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 41-year-old woman is brought to the emergency department with the acute-onset of severe abdominal pain for the past 2 hours. She has a history of frequent episodes of vague abdominal pain, but they have never been this severe. Every time she has had pain, it would resolve after eating a meal. Her past medical history is otherwise insignificant. Her vital signs include: blood pressure 121/77 mm Hg, pulse 91/min, respiratory rate 21/min, and temperature 37°C (98.6°F). On examination, her abdomen is flat and rigid. Which of the following is the next best step in evaluating this patient’s discomfort and stomach pain by physical exam?", "answer": "Auscultate the abdomen", "options": {"A": "Elicit shifting dullness of the abdomen", "B": "Percuss the point of maximal pain", "C": "Perform light palpation at the point of maximal pain", "D": "Attempt to perform a deep, slow palpation with quick release", "E": "Auscultate the abdomen"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A group of scientists is verifying previous research on DNA replication. In the picture is the theoretical structure for tRNA. Where is the binding site for an amino acid?", "answer": "A", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old college student is brought to the ED after a motor vehicle accident. Primary and secondary surveys reveal no significant compromise to his airway, his cardiovascular system, or to his motor function. However, his conjunctiva appear injected and he maintains combative behavior towards staff. What test will confirm potential substance use?", "answer": "Gas chromatography / mass spectrometry (GC/MS)", "options": {"A": "Polymerase chain reaction", "B": "Urine immunoassay", "C": "Western blot", "D": "Gas chromatography / mass spectrometry (GC/MS)", "E": "Breath alcohol test"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old G3P3 presents to her gynecologist complaining of painful intercourse. She reports a 6-month history of intermittent dryness, itching, and burning during intercourse. Upon further questioning, she also reports poor sleep and occasional periods during which she feels very warm and sweats profusely. Her past medical history is significant for poorly controlled hypertension and a 10 pack-year smoking history. She takes hydrochlorothiazide and enalapril. Her temperature is 99.3°F (37.4°C), blood pressure is 135/85 mmHg, pulse is 90/min, and respirations are 18/min. On examination, she is a healthy female in no distress. Pelvic examination reveals no adnexal or cervical motion tenderness. Which of the following sets of hormone levels are most likely to be found in this patient?", "answer": "Decreased estrogen, increased FSH, increased LH, increased GnRH", "options": {"A": "Decreased estrogen, decreased FSH, decreased LH, decreased GnRH", "B": "Increased estrogen, decreased FSH, decreased LH, decreased GnRH", "C": "Decreased estrogen, decreased FSH, decreased LH, increased GnRH", "D": "Decreased estrogen, increased FSH, increased LH, increased GnRH", "E": "Normal estrogen, normal FSH, normal LH, normal GnRH"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An otherwise healthy 28-year-old woman comes to the physician because of a 14-day history of a painful red nodules on her legs associated with malaise and mild joint pains. She reports that the nodules were initially smaller and distinct but some have fused together over the past 3–4 days and now appear like bruises. There is no preceding history of fever, trauma, or insect bites. Her vital signs are within normal limits. A photograph of the tender lesions on her shins is shown. The remainder of the examination shows no abnormalities. Complete blood count and antistreptolysin O (ASO) titers are within the reference range. Erythrocyte sedimentation rate is 30 mm/h. Which of the following is the most appropriate next step in management ?", "answer": "X-ray of the chest", "options": {"A": "Oral amoxicillin", "B": "Oral isoniazid", "C": "X-ray of the chest", "D": "Stool culture", "E": "Skin biopsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought to his pediatrician’s office with complaints of watery diarrhea for the past 2 weeks. He has had a couple of episodes of watery diarrhea in the past, but this is the first time it failed to subside over the course of a few days. His father tells the doctor that the child has frothy stools with a distinct foul odor. Other than diarrhea, his parents also mention that he has had several bouts of the flu over the past 2 years and has also been hospitalized twice with pneumonia. On examination, the child is underweight and seems to be pale and dehydrated. His blood pressure is 80/50 mm Hg, the pulse rate of 110/min, and the respiratory rate is 18/min. Auscultation of the lungs reveals rhonchi. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Faulty transmembrane ion channel", "options": {"A": "Faulty transmembrane ion channel", "B": "Defect in the lysosomal trafficking regulator", "C": "Primary ciliary dyskinesia", "D": "Accumulation of branched chain amino acids", "E": "Dysfunction of phenylalanine hydroxylase"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old primigravida woman visits the clinic in her 22nd week of gestation as part of her antenatal care. She has no complaints. Past medical history is unremarkable. Her only medication is a prenatal vitamin. Her temperature is 37.0°C (98.6°F), blood pressure is 110/70 mm Hg, pulse rate is 78/min, and respiration rate is 20/min. Physical examination is consistent with the gestational age of her pregnancy with no abnormalities noted. Urine dipstick is normal. Which of the following is the current primary location for fetal myelopoiesis at this stage of development?", "answer": "Liver", "options": {"A": "Yolk sac", "B": "Liver", "C": "Thymus", "D": "Aorta-gonad-mesonephros region", "E": "Spleen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 73-year-old man presents to the outpatient clinic complaining of chest pain with exertion. He states that resting for a few minutes usually resolves the chest pain. Currently, he takes 81 mg of aspirin daily. He has a blood pressure of 127/85 mm Hg and heart rate of 75/min. Physical examination reveals regular heart sounds and clear lung sounds bilateral. Which medication regimen below should be added?", "answer": "Metoprolol and a statin daily. Sublingual nitroglycerin as needed.", "options": {"A": "Amlodipine daily. Sublingual nitroglycerin as needed.", "B": "Metoprolol and a statin daily. Sublingual nitroglycerin as needed.", "C": "Clopidogrel and amlodipine daily. Sublingual nitroglycerin as needed.", "D": "Metoprolol and ranolazine daily. Sublingual nitroglycerin as needed.", "E": "Amlodipine and a statin daily. Sublingual nitroglycerin as needed."}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 8-year-old African-American boy is brought to the emergency room with severe pain in both hands. His mother says that the patient had a fever with a cough a couple of days ago. Family history is positive for an uncle who died from a blood disease. A peripheral blood smear of this patient is shown in the image. Which of the following is the most likely mechanism for this patient’s disease?", "answer": "Missense mutation", "options": {"A": "Nonsense mutation", "B": "Frameshift mutation", "C": "Mismatch repair", "D": "Silent mutation", "E": "Missense mutation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old Caucasian man visits the nephrology outpatient clinic for a follow-up appointment. He was previously diagnosed with stage G3a chronic kidney disease (CKD) and albuminuria stage A2. He follows strict dietary recommendations and takes enalapril. He has a history of benign prostatic hyperplasia which has been complicated by urinary tract obstruction. His vitals are stable, and his blood pressure is within the recommended limits. His most recent laboratory studies are as follows:\nSerum sodium 140 mEq/L\nSerum potassium 5.8 mEq/L\nSerum chloride 102 mEq/L\nSerum phosphate 4.0 mg/dL\nHemoglobin 11.5 mg/dL\nAlbumin excretion rate (AER) 280 mg/day\nWhich of the following is the best strategy in the management of this patient?", "answer": "Addition of patiromer", "options": {"A": "Removal of enalapril", "B": "Addition of furosemide", "C": "Observation", "D": "Addition of patiromer", "E": "Addition of sevelamer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old girl is brought to a medical office for evaluation of persistent abdominal pain that has worsened over the past 24 hours. The mother states that the girl often has constipation which has worsened over the last 3 days. The mother denies that the girl has had bloody stools. The girl has not had a bowel movement or passed flatulence in 72 hours. She has vomited 3 times since last night and refuses to eat. She has no significant medical history, including no history of surgeries. On exam, there are no abdominal masses; however, the upper abdomen is distended and tympanic. What is the most likely underlying cause of the girl’s symptoms?", "answer": "Malrotation of the gut", "options": {"A": "Volvulus", "B": "Malrotation of the gut", "C": "Pyloric stenosis", "D": "Duodenal atresia", "E": "Meckel’s diverticulum"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year old man presents for a well physical examination. He reports his diet is suboptimal, but otherwise reports a healthy lifestyle. He has no past medical history and only takes a multivitamin. He has a blood pressure of 116/74 mm Hg and a pulse of 76/min. On physical examination, he is in no acute distress, has no cardiac murmurs, and his lung sounds are clear to auscultation bilaterally. You order a lipid panel that returns as follows: LDL 203, HDL 37, TG 292. Of the following, which medication should be initiated?", "answer": "Atorvastatin 40 mg", "options": {"A": "Simvastatin 10 mg daily", "B": "Ezetimibe 10 mg daily", "C": "Fenofibrate 145 mg daily", "D": "Atorvastatin 40 mg", "E": "Colesevelam 3.75 grams daily"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old man presents to the emergency department with complaints of right-sided weakness and slurring of speech for 1 hour. There is no history of head trauma, myocardial infarction, recent surgery, gastrointestinal or urinary bleeding. He has hypertension, chronic atrial fibrillation, and a 20 pack-year cigarette smoking history. The medication list includes valsartan and rivaroxaban. The vital signs include: blood pressure 180/92 mm Hg, pulse 144/min and irregular, and temperature 37.2°C (99.0°F). On physical examination, there is a facial asymmetry with a deviation of angle of mouth to the left side on smiling. Muscle strength is reduced in both upper and lower limbs on the right side while on the left side it’s normal. Random blood glucose is 104 mg/dL. A complete blood count is normal. A CT scan of the head is shown in the image. What is the most appropriate next step in the management of this patient?", "answer": "Aspirin", "options": {"A": "Amiodarone", "B": "Aspirin", "C": "Heparin", "D": "Metoprolol", "E": "Tissue plasminogen activator"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 18-month-old girl is brought to the pediatrician’s office for failure to thrive and developmental delay. The patient’s mother says she has not started speaking and is just now starting to pull herself up to standing position. Furthermore, her movement appears to be restricted. Physical examination reveals coarse facial features and restricted joint mobility. Laboratory studies show increased plasma levels of several enzymes. Which of the following is the underlying biochemical defect in this patient?", "answer": "Failure of mannose phosphorylation", "options": {"A": "Failure of mannose phosphorylation", "B": "Inappropriate degradation of lysosomal enzymes", "C": "Congenital lack of lysosomal formation", "D": "Inappropriate protein targeting to endoplasmic reticulum", "E": "Misfolding of nuclear proteins"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 29-year-old man presents to the emergency department with chest pain and fatigue for the past week. The patient is homeless and his medical history is not known. His temperature is 103°F (39.4°C), blood pressure is 97/58 mmHg, pulse is 140/min, respirations are 25/min, and oxygen saturation is 95% on room air. Physical exam is notable for scars in the antecubital fossa and a murmur over the left sternal border. The patient is admitted to the intensive care unit and is treated appropriately. On day 3 of his hospital stay, the patient presents with right-sided weakness in his arm and leg and dysarthric speech. Which of the following is the most likely etiology of his current symptoms?", "answer": "Septic emboli", "options": {"A": "Bacterial meningitis", "B": "Septic emboli", "C": "Herpes simplex virus encephalitis", "D": "Intracranial hemorrhage", "E": "Thromboembolic stroke"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 69-year-old man comes to the physician because of a 3-month history of urinary urgency, nocturia, and progressive pain in his lower back. The pain is worse at night and does not respond to ibuprofen. Rectal examination shows an enlarged, asymmetric prostate with a nodular surface. Prostate-specific antigen concentration is 11 ng/ml (N < 4). A biopsy of the prostate shows a high-grade adenocarcinoma. A CT scan of the pelvis shows multiple osteoblastic lesions of the lumbar spine. The patient is started on a drug that competes with androgens for interaction with the testosterone receptors. Treatment with which of the following drugs was most likely initiated in this patient?", "answer": "Flutamide", "options": {"A": "Leuprolide", "B": "Flutamide", "C": "Degarelix", "D": "Docetaxel", "E": "Finasteride"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 49-year-old man presents with an 11-month history of progressive fatigue. He denies any night sweats, weight loss, abdominal pain, nausea, vomiting, change in bowel habits, or bleeding. He has no significant past medical history. His vital signs include: temperature 37.0°C (98.6°F), blood pressure 119/81 mm Hg, pulse 83/min, and respiratory rate 19/min. On physical examination, mild splenomegaly is noted on abdominal percussion. Laboratory findings are significant for a leukocyte count of 16,700/mm3 and a low serum leukocyte alkaline phosphatase (LAP) score. A bone marrow biopsy is performed, which shows marked hypercellularity with a clear dominance of granulocytes. Cytogenetic analysis is positive for the Ph1 gene. Which of the following is the best course of treatment for this patient?", "answer": "Imatinib", "options": {"A": "Hydroxyurea", "B": "Interferon-α-2b", "C": "Rituximab", "D": "Cytarabine", "E": "Imatinib"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old woman is brought to the emergency department by her neighbors 30 minutes after they found her unconscious in her yard. Her neighbors report that she has been spending more time at home by herself because she recently lost her job. On arrival, she is unable to provide a history. She appears anxious. Her pulse is 76/min, respirations are 13/min, and blood pressure is 114/72 mm Hg. Examination shows significant weakness of the left upper and lower extremities. She is unable to plantarflex the ankle while supine. She is able to stand on her toes. Her gait is unsteady. Deep tendon reflexes are 3+ and symmetric. A CT scan of the head shows no abnormalities. An MRI of the brain and MR angiography show no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Conversion disorder", "options": {"A": "Conversion disorder", "B": "Malingering", "C": "Somatic symptom disorder", "D": "Acute stress disorder", "E": "Acute hemorrhagic stroke"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 12-year-old boy is brought to the physician because of difficulty in walking for 5 months. His mother reports that he has trouble keeping his balance and walking without support. Over the past year, he has started to have difficulty seeing in the dark and his hearing has been impaired. Examination shows marked scaling of the skin on the face and feet and a shortened 4th toe. Muscle strength is 3/5 in the lower extremities and 4/5 in the upper extremities. Sensation to pinprick is symmetrically decreased over the legs. Fundoscopy shows peripheral pigment deposits and retinal atrophy. His serum phytanic acid concentration is markedly elevated. The patient's condition is most likely caused by a defect in which of the following cellular structures?", "answer": "Peroxisomes", "options": {"A": "Peroxisomes", "B": "Mitochondria", "C": "Smooth endoplasmic reticulum", "D": "Myofilaments", "E": "Proteasomes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 40-year-old man presents with a rash, oral lesions, and vision problems for 5 days. He says the rash started as a burning feeling on his face and the upper part of his torso, but soon red spots appeared in that same distribution. The spots grew in size and spread to his upper extremities. The patient says the spots are painful but denies any associated pruritus. He says the painful oral lesions appeared about the same time as the rash. For the past 3 days, he also says he has been having double vision and dry, itchy eyes. He reports that he had a mild upper respiratory infection for a few days that preceded his current symptoms. The patient denies any chills, hematuria, abdominal or chest pain, or similar symptoms in the past. Past medical history is significant for a severe urinary tract infection diagnosed 3 weeks ago for which he has been taking trimethoprim-sulfamethoxazole. The vital signs include: temperature 38.3℃ (101.0℉), blood pressure 110/60 mm Hg, respiratory rate 20/min, and pulse 108/min. On physical examination, the patient has severe painful erosions of the oral mucosa. There are multiple fluid-filled vesicles and bullae averaging 3 mm in diameter with a surrounding erythematous ring that involve only the upper torso and extensor surfaces of upper extremities. Several of the lesions have ruptured, resulting in sloughing off of the epidermal layer. There is a prominent conjunctival injection present. Ophthalmic examination reveals mild bilateral corneal abrasions without any evidence of frank ulceration. Laboratory findings are significant for the following:\nWhite blood cell (WBC) count 8,500/mm3\nRed blood cell (RBC) count 4.20 x 106/mm3\nHematocrit 41.5%\nHemoglobin 14.0 g/dL\nPlatelet count 215,000/mm3\nC-reactive protein (CRP) 86 mg/L\nUrine and blood cultures are pending. Which of the following would confirm the most likely diagnosis in this patient?\n ", "answer": "Biopsy and histopathologic analysis of skin lesions", "options": {"A": "Gram stain and culture of skin sample", "B": "Biopsy and histopathologic analysis of skin lesions", "C": "Direct immunofluorescence analysis of perilesional skin biopsy", "D": "Urine collection (24-hour)", "E": "Flow cytometry"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the physician for the evaluation of fever, difficulty breathing, and coughing for the past week. In the past year, he has had four sinus infections, three upper respiratory tract infections, and an episode of severe bronchiolitis requiring hospitalization. Since birth, he has had multiple episodes of oral thrush treated with nystatin, as well as chronic diarrhea and failure to thrive. His temperature is 38.0°C (100.4°F), pulse is 130/min, respirations are 38/min, and blood pressure is 106/63 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 88%. Auscultation of the lungs show bilateral crackles and wheezing. Examination shows a prominent nasal bridge, hypoplastic wing of the nose, a shortened chin, and dysplastic ears. An x-ray of the chest shows hyperinflation of the lungs, interstitial infiltrates, and atelectasis. A nasopharyngeal aspirate test for respiratory syncytial virus (RSV) is positive. This patient most likely has a deficiency of which of the following?", "answer": "T cells", "options": {"A": "B cells", "B": "T cells", "C": "Interleukin-12 receptor", "D": "B and T cells", "E": "Leukocyte adhesion\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A morbidly obese 43-year-old man presents for elective bariatric surgery after previously failing several non-surgical weight loss plans. After discussing the risks and benefits of several different procedures, a sleeve gastrectomy is performed. During the surgery, the surgeon begins by incising into the right half of the greater curvature of the stomach. Which of the following arteries most likely directly provides the blood supply to this region of the stomach?", "answer": "Right gastroepiploic artery", "options": {"A": "Short gastric arteries", "B": "Splenic artery", "C": "Right gastric artery", "D": "Right gastroepiploic artery", "E": "Right gastroduodenal artery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought in by his parents for recurrent abdominal pain. The child has been taken out of class 5 times this past week for abdominal pain that resulted in him being sent home. The mother reports that her son's stools have remained unchanged during this time and are brown in color, without blood, and with normal consistency and scent. She also notes that while at home he seems to be his usual self and does not complain of any symptoms. Of note she presents to you that she has been preparing her son's lunches which consist of couscous, vegetables, fried rice, and chicken. The patient denies difficulty with producing stool and does not complain of any functional pain. The child's vitals and labs including BMP and CBC are unremarkable and within normal limits. An abdominal exam is performed and there is no tenderness upon palpation, and the abdomen is soft and non-distended. After a conversation with the child exploring his symptoms, which of the following is the next step in management for this child?", "answer": "Begin cognitive behavioral therapy", "options": {"A": "Increase oral hydration and fiber intake", "B": "Check the stool for fecal red blood cells and leukocytes", "C": "Perform a stool culture", "D": "Begin treatment with ciprofloxacin", "E": "Begin cognitive behavioral therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old woman comes to the physician for the evaluation of a 4-month history of reddening of the nose and cheeks. She has no itching or pain. She first noticed the redness while on a recent holiday in Spain, where she stayed at the beach and did daily wine tastings. She has tried several brands of sunscreen, stopped going outside in the middle of the day, and has not drunk alcohol since her trip, but the facial redness persists. She has no history of serious illness. Her younger sister has acne vulgaris, and her mother has systemic lupus erythematosus. The patient reports that she has had a lot of stress lately due to relationship problems with her husband. She does not smoke. Her vital signs are within normal limits. Examination shows erythema of the nose, chin, and medial cheeks with scant papules and telangiectasias. There are no comedones or blisters. The remainder of the examination shows no abnormalities. In addition to behavioral modifications, which of the following is the most appropriate initial treatment?", "answer": "Topical metronidazole", "options": {"A": "Topical corticosteroids", "B": "Topical benzoyl peroxide", "C": "Oral isotretinoin", "D": "Oral hydroxychloroquine", "E": "Topical metronidazole"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old previously healthy woman presents to her PCP reporting cessation of menses for the past 6 months. Previously, her period occurred regularly, every 30 days. She also complains of decreased peripheral vision, most noticeably when she is driving her car. She denies any recent sexual activity and a pregnancy test is negative. Upon further work-up, what other physical findings may be discovered?", "answer": "Decreased bone density", "options": {"A": "Pregnancy", "B": "Breast mass", "C": "Decreased bone density", "D": "Enlarged thyroid", "E": "Renal failure"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 13-year-old boy is brought to the physician because of bleeding from his lips earlier that day. He has a history of recurrent nosebleeds since childhood. His father has a similar history of recurrent nosebleeds. He is at the 60th percentile for height and weight. Examination shows multiple, small dilated capillaries over the lips, nose, and fingers. The remainder of the examination shows no abnormalities. Which of the following conditions is this patient at increased risk for?", "answer": "High-output cardiac failure", "options": {"A": "Glaucoma", "B": "Acute leukemia", "C": "Renal cell carcinoma", "D": "High-output cardiac failure", "E": "Gastrointestinal polyps"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old G1P1 has an uncomplicated vaginal delivery and delivers a newborn boy at 39 + 1 weeks. The APGAR scores are 8 and 9 at 1 and 5 minutes, respectively. Shortly after the delivery, the child is put on his mother’s chest for skin-to-skin and the mother is encouraged to initiate breastfeeding. Which of the following cels produces the hormone responsible for establishing lactation during this process?", "answer": "Lactotropes", "options": {"A": "Gonadotropes", "B": "Thyrotropes", "C": "Lactotropes", "D": "Corticotropes", "E": "Somatotropes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old man presents to the physician because of dizziness and palpitations for the past 12 hours and fever, malaise, headache, and myalgias for the past week. The patient traveled into the woods of Massachusetts 4 weeks ago. He has no known chronic medical conditions, and there is no history of substance use. His temperature is 38.3°C (100.9°F), pulse is 52/min, respirations are 16/min, and blood pressure is 126/84 mm Hg. His physical examination shows a single, 10-cm, round, erythematous lesion with a bull’s-eye pattern in the right popliteal fossa. His electrocardiogram shows Mobitz I second-degree atrioventricular (AV) block. The complete blood cell count and serum electrolyte levels are normal, but the erythrocyte sedimentation rate is 35 mm/hour. What is the most likely cause of the patient’s cardiac symptoms?", "answer": " Spirochete infection", "options": {"A": "Mycoplasma infection", "B": " Spirochete infection", "C": "Systemic fungal infection", "D": "Viral infection transmitted by Aedes aegypti mosquito bite", "E": "Sexually transmitted bacterial infection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old boy is presented to the clinic by his mother due to a peeling erythematous rash on his face, back, and buttocks which started this morning. Two days ago, the patient’s mother says his skin was extremely tender and within 24 hours progressed to desquamation. She also says that, for the past few weeks, he was very irritable and cried more than usual during diaper changes. The patient is up to date on his vaccinations and has been meeting all developmental milestones. No significant family history. On physical examination, the temperature is 38.4°C (101.1°F) and the pulse is 70/min. The epidermis separates from the dermis by gentle lateral stroking of the skin. Systemic antibiotics are prescribed, and adequate fluid replacement is provided. Which of the following microorganisms most likely caused this patient’s condition?", "answer": "Staphylococcus aureus", "options": {"A": "Neisseria meningitidis", "B": "Bacillus anthracis", "C": "Clostridium sp.", "D": "Streptococcus sp.", "E": "Staphylococcus aureus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-month-old boy presents for a routine checkup. The patient immigrated from the Philippines with his parents a few months ago. No prior immunization records are available. The patient’s mother claims that he had a series of shots at 6 months of age which gave him a severe allergic reaction with swelling of the tongue and the face. She also remembers that he had the same reaction when she introduced solid foods to his diet, including carrots, eggs, and bananas. Which of the following vaccinations are not recommended for this patient?", "answer": "Intramuscular influenza vaccine", "options": {"A": "Measles, mumps, and rubella (MMR) vaccine", "B": "Intramuscular influenza vaccine", "C": "Varicella vaccine", "D": "Intranasal influenza vaccine", "E": "Hepatitis B vaccine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old man is brought to the emergency department by a friend after he was found lying unconscious outside his front door. The friend reports that they were “pretty drunk” the previous night, and she had dropped her friend off at his home and driven off. When she came back in the morning, she found him passed out on the ground next to the doorstep. On arrival, he is conscious and cooperative. He reports feeling cold, with severe pain in his hands and face. He remembers having lost his gloves last night. His rectal temperature is 35.2°C (95.3°F), pulse is 86/min, respirations are 17/min, and blood pressure is 124/58 mm Hg. Examination shows decreased sensations over the distal fingers, which are cold to touch. The skin over the distal phalanges is cyanotic, hard, waxy, and tender, with surrounding edema. Laboratory studies are within the reference range. An x-ray of the chest and ECG show no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Immersion of affected extremities in warm water", "options": {"A": "Debridement of the affected tissue", "B": "Intra-arterial administration of tissue plasminogen activator", "C": "Intravenous administration of warmed crystalloid", "D": "Intravenous administration of antibiotics", "E": "Immersion of affected extremities in warm water"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 16-year-old woman presents to the emergency department for evaluation of acute vomiting and abdominal pain. Onset was roughly 3 hours ago while she was sleeping. She has no known past medical history. Her family history is positive for hypothyroidism and diabetes mellitus in her maternal grandmother. On examination, she is found to have fruity breath and poor skin turgor. She appears fatigued and her consciousness is slightly altered. Laboratory results show a blood glucose level of 691 mg/dL, sodium of 125 mg/dL, and elevated serum ketones. Of the following, which is the next best step in patient management?", "answer": "Administer IV fluids and insulin", "options": {"A": "Administer IV fluids and insulin", "B": "Discontinue metformin; initiate basal-bolus insulin", "C": "Discontinue metformin; initiate insulin aspart at mealtimes", "D": "Discontinue sitagliptin; initiate basal-bolus insulin", "E": "Discontinue metformin; initiate insulin glargine 10 units at bedtime"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-year-old African-American girl is brought to the physician because of multiple episodes of bilateral leg pain for 4 months. The pain is crampy in nature, lasts up to an hour, and occurs primarily before her bedtime. Occasionally, she has woken up crying because of severe pain. The pain is reduced when her mother massages her legs. She has no pain while attending school or playing. Her mother has rheumatoid arthritis. The patient's temperature is 37°C (98.6°F), pulse is 90/min and blood pressure is 94/60 mm Hg. Physical examination shows no abnormalities. Her hemoglobin concentration is 12.1 g/dL, leukocyte count is 10,900/mm3 and platelet count is 230,000/mm3. Which of the following is the most appropriate next best step in management?", "answer": "Reassurance", "options": {"A": "Antinuclear antibody", "B": "Pramipexole therapy", "C": "Nafcillin therapy", "D": "X-ray of the lower extremities", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 37-year-old man makes an appointment with his primary care physician because he has been feeling tired and is no longer able to play on a recreational soccer team. He also says his coworkers have commented that he appears pale though he has not noticed any changes himself. He says that he has been generally healthy and that the only notable event that happened in the last year is that he went backpacking all over the world. Based on clinical suspicion, a series of blood tests are performed with partial results presented below:\n\nHemoglobin: 9.8 g/dL\nPlatelet count: 174,000/mm^3\nMean corpuscular volume: 72 µm^3 (normal: 80-100 µm^3)\nIron: 22 µg/dL (normal: 50-170 µg/dL)\nFerritin: 8 ng/mL (normal: 15-200 ng/mL)\nLactate dehydrogenase: 57 U/L (normal: 45-90 U/L)\nUrine hemoglobin: absent\n\nInfection with which of the following types of organisms could lead to this pattern of findings?", "answer": "Nematode", "options": {"A": "Double-stranded virus", "B": "Nematode", "C": "Mosquito-born protozoa", "D": "Single-stranded virus", "E": "Tick-born protozoa"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year-old male presents to your office for a regularly scheduled check-up. The patient was diagnosed with type II diabetes mellitus two years ago. To date, diet, exercise, and metformin have failed to control his elevated blood glucose. Past medical history is also significant for hypertension. The patient does not smoke or use cigarettes. Laboratory values show a hemoglobin A1c (HbA1c) of 8.5%. You decide to add sitagliptin to the patient’s medication regimen. Which of the following is the direct mechanism of action of sitagliptin?", "answer": "Inhibits degradation of endogenous incretins", "options": {"A": "Inhibits degradation of endogenous incretins", "B": "Inhibits alpha-glucosidases at the intestinal brush border", "C": "Activates transcription of PPARs to increase peripheral sensitivity to insulin", "D": "Depolarizes potassium channels in pancreatic beta cells", "E": "Increases secretion of insulin in response to oral glucose loads and delays gastric emptying"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old woman presents with her husband because of left leg pain and swelling of 3 days’ duration. He has a history of type 2 diabetes mellitus and recent hospitalization for congestive heart failure exacerbation. On physical examination, the left calf is 4 cm greater in circumference than the right. Pitting edema is present on the left leg and there are superficial dilated veins. Venous duplex ultrasound shows an inability to fully compress the lumen of the profunda femoris vein. Which of the following is the most likely diagnosis?", "answer": "Deep venous thrombosis", "options": {"A": "Superficial venous thrombophlebitis", "B": "Erythema nodosum", "C": "Lymphangitis", "D": "Deep venous thrombosis", "E": "Ruptured popliteal cyst"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old woman presents to the emergency room complaining of chest pain. She reports a 4-hour history of dull substernal pain radiating to her jaw. Her history is notable for hypertension, diabetes mellitus, and alcohol abuse. She has a 30 pack-year smoking history and takes lisinopril and metformin but has an allergy to aspirin. Her temperature is 99.1°F (37.3°C), blood pressure is 150/90 mmHg, pulse is 120/min, and respirations are 22/min. Physical examination reveals a diaphoretic and distressed woman. An electrocardiogram reveals ST elevations in leads I, aVL, and V5-6. She is admitted with plans for immediate transport to the catheterization lab for stent placement. What is the mechanism of the next medication that should be given to this patient?", "answer": "ADP receptor inhibitor", "options": {"A": "Thrombin inhibitor", "B": "Phosphodiesterase activator", "C": "Vitamin K epoxide reductase inhibitor", "D": "ADP receptor inhibitor", "E": "Cyclooxygenase activator"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old woman presents with left lower limb swelling. She first noticed her left leg was swollen about 2 weeks ago. She denies any pain and initially thought the swelling would subside on its own. Past medical history is significant for hypertension and hyperlipidemia. She is a smoker with a 35 pack-year history and an occasional drinker. She takes chlorthalidone, lisinopril, atorvastatin and a multivitamin. On physical examination, her left leg appears larger than her right with 2+ pitting edema up to her knee. She also has a few distended superficial veins along the posterior aspect of her left leg. Lower extremities have 2+ pulses bilaterally. The ultrasound of her left lower thigh and leg shows an obstructing thrombosis of the distal portion of the femoral vein. Which of the following veins help to prevent this patient’s condition from happening?", "answer": "Perforator veins", "options": {"A": "Giacomini vein", "B": "Perforator veins", "C": "Accessory saphenous vein", "D": "Deep femoral vein", "E": "Fibular vein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old man comes to the physician because of headaches and blurry vision for the past 6 months. He also reports frequent episodes of vomiting over the last month. His father has died of renal cell carcinoma at the age of 37 years. Examination shows 20/40 vision bilaterally. Fundoscopic examination shows bilateral optic disc swelling and growth of capillary vessels in the temporal peripheral retina. An MRI of the brain shows an infratentorial mass. The patient undergoes surgical resection of the mass. A photomicrograph of the resected specimen is shown. Which of the following is the most likely diagnosis?", "answer": "Hemangioblastoma", "options": {"A": "Medulloblastoma", "B": "Glioblastoma", "C": "Oligodendroglioma", "D": "Hemangioblastoma", "E": "Ependymoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old man presents to his psychiatrist for a follow-up visit. He was diagnosed with schizophrenia 6 months ago and has been taking fluphenazine. He says that his symptoms are well controlled by the medication, and he no longer has auditory hallucinations. The psychiatrist also notes that his delusions and other psychotic symptoms have improved significantly. However, the psychiatrist notices something while talking to the patient that prompts him to say, “I know the drug has effectively controlled your symptoms but I think you should discontinue it now otherwise this side effect is likely to be irreversible.” Which of the following did the psychiatrist most likely notice in this patient?", "answer": "Choreoathetoid movements of face", "options": {"A": "Resting tremors", "B": "Crossing and uncrossing legs constantly", "C": "Reduced spontaneous movements while walking ", "D": "Involuntary sustained twisting of neck", "E": "Choreoathetoid movements of face"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 8-year-old boy and his 26-year-old babysitter are brought into the emergency department with severe injuries caused by a motor vehicle accident. The child is wheeled to the pediatric intensive care unit with a severe injury to his right arm, as well as other external and internal injuries. He is hemorrhaging and found to be hemodynamically unstable. He subsequently requires transfusion and surgery, and he is currently unconscious. The pediatric trauma surgeon evaluates the child’s arm and realizes it will need to be amputated at the elbow. Which of the following is the most appropriate course of action to take with regards to the amputation?", "answer": "Amputate the child’s arm at the elbow joint", "options": {"A": "Amputate the child’s arm at the elbow joint", "B": "Wait for the child to gain consciousness to obtain his consent to amputate his arm", "C": "Wait for the child’s babysitter to recover from her injuries to obtain her consent to amputate the child’s arm", "D": "Find the child’s parents to obtain consent to amputate the child’s arm", "E": "Obtain an emergency court order from a judge to obtain consent to amputate the child’s arm"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man comes to the physician because of difficulties achieving an erection for the past year. A medication is prescribed that inhibits cyclic GMP phosphodiesterase type 5. Which of the following is the most likely site of action of the prescribed drug?", "answer": "Corpus cavernosum", "options": {"A": "Corpus cavernosum", "B": "Prostate smooth muscle", "C": "Corpus spongiosum", "D": "Pelvic splanchnic nerves", "E": "Pudendal nerve"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old woman undergoes an abdominal hysterectomy. She develops pain and discharge at the incision site on the fourth postoperative day. The past medical history is significant for diabetes of 12 years duration, which is well-controlled on insulin. Pus from the incision site is sent for culture on MacConkey agar, which shows white-colorless colonies. On blood agar, the colonies were green. Biochemical tests reveal an oxidase-positive organism. Which of the following is the most likely pathogen?", "answer": "Pseudomonas aeruginosa", "options": {"A": "Staphylococcus aureus", "B": "Staphylococcus epidermidis", "C": "Enterococcus faecalis", "D": "Streptococcus pyogenes", "E": "Pseudomonas aeruginosa"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old woman comes to the emergency department because of difficulty walking for the past 4 hours. She first noticed her symptoms after getting up this morning and her foot dragging while walking. She feels tired. She has a history of chronic sinusitis. Six months ago, she was diagnosed with asthma. Current medications include an albuterol inhaler and inhaled corticosteroids. Her temperature is 38.9°C (102°F), pulse is 80/min, and her blood pressure is 140/90 mm Hg. Auscultation of her lungs shows diffuse wheezing over bilateral lung fields. Physical examination shows tender subcutaneous nodules on the extensor surfaces of the elbows. There are palpable, non-blanching erythematous lesions on both shins. Dorsiflexion of the right foot is impaired. Sensation to pinprick, light touch, and vibration is decreased over the ulnar aspect of the left forearm. Laboratory studies show:\nHemoglobin 11.3 g/dL\nLeukocyte count 24,500\nSegmented neutrophils 48%\nEosinophils 29%\nLymphocytes 19%\nMonocytes 4%\nPlatelet count 290,000/mm3\nSerum\nUrea nitrogen 32 mg/dL\nCreatinine 1.85 mg/dL\nUrine\nBlood 2+\nProtein 3+\nWhich of the following is the most likely diagnosis in this patient?\"", "answer": "Eosinophilic granulomatosis with polyangiitis\n\"", "options": {"A": "Granulomatosis with polyangiitis", "B": "Goodpasture syndrome", "C": "Henoch-Schönlein purpura", "D": "Excessive glucocorticoid use", "E": "Eosinophilic granulomatosis with polyangiitis\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 21-year-old medical student is studying different types of necrosis and tissue injuries. In the pathology laboratory, he observes different dead tissues under the microscope and notices the changes that are occurring as a function of time. After serial observations, he deduced that coagulation necrosis is...?", "answer": "Characterized by the preservation of cellular shape", "options": {"A": "The result of denaturation of glucose", "B": "The result of hydrolytic enzymes", "C": "Characterized by the preservation of cellular shape", "D": "Characteristic of brain ischemia", "E": "Commonly associated with acute pancreatic necrosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old male presents to the emergency room with difficulty breathing. He is accompanied by his wife who reports that they were eating peanuts while lying in bed on their backs when he suddenly started coughing profusely. He has a significant cough and has some trouble breathing. His past medical history is notable for obesity, obstructive sleep apnea, seasonal allergies, and alcohol abuse. He uses a continuous positive airway pressure machine nightly. His medications include cetirizine and fish oil. He has a 10 pack-year smoking history. His temperature is 98.6°F (37°C), blood pressure is 125/30 mmHg, pulse is 110/min, and respirations are 23/min. Which of the following lung segments is most likely affected in this patient?", "answer": "Superior segment of right inferior lobe", "options": {"A": "Inferior segment of left inferior lobe", "B": "Anterior segment of right superior lobe", "C": "Inferior segment of right inferior lobe", "D": "Superior segment of right inferior lobe", "E": "Posterior segment of right superior lobe"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old woman, gravida 1, para 0, at 10 weeks gestation comes to the physician for her first prenatal visit. Today, she feels well. She has no history of serious illness. Her pulse is 75/min and blood pressure is 110/74 mm Hg. Examination shows no abnormalities. Ultrasonography shows a pregnancy consistent in size with a 10-week gestation. Serum studies in this patient are most likely to show which of the following sets of laboratory values?\n $$$ Thyroid-binding globulin %%% Free Triiodothyronine (T3) %%% Free Thyroxine (T4) %%% Total T3+T4 $$$", "answer": "↑ normal normal ↑", "options": {"A": "↑ normal normal ↑", "B": "↓ normal normal ↓", "C": "Normal normal normal normal", "D": "Normal ↑ ↑ ↑", "E": "↓ ↓ normal ↓"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-day-old boy is monitored in the well baby nursery. He was born to a G1P1 mother at 36 weeks gestation. The child is doing well, and the mother is recovering from vaginal delivery. On physical exam, there is an arousable infant who is crying vigorously and is mildly cyanotic. A red reflex is noted bilaterally on ophthalmologic exam. The infant's fontanelle is soft, and his sucking reflex is present. A positive Babinski sign is noted on physical exam bilaterally. A continuous murmur is auscultated on cardiac exam. Which of the following would most likely have prevented the abnormal finding in this infant?", "answer": "Indomethacin", "options": {"A": "Betamethasone", "B": "Delivery at 40 weeks gestation", "C": "Folic acid", "D": "Indomethacin", "E": "Prostaglandins"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old girl is brought to the physician for the evaluation of fatigue for the past 6 months. During this period, she has had a 5-kg (11-lbs) weight loss. She states that she has no friends. When she is not in school, she spends most of her time in bed. She has no history of serious illness. Her mother has major depressive disorder. She appears pale and thin. She is at 25th percentile for height, 10th percentile for weight, and 20th percentile for BMI; her BMI is 19.0. Her temperature is 37°C (98.6°F), pulse is 65/min, and blood pressure is 110/70 mm Hg. Examination shows dry skin, brittle nails, and calluses on the knuckles. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12.3 g/dL\nSerum\nNa+ 133 mEq/L\nCl- 90 mEq/L\nK+ 3.2 mEq/L\nHCO3- 30 mEq/L\nCa+2 7.8 mg/dL\nWhich of the following is the most likely diagnosis?\"", "answer": "Bulimia nervosa", "options": {"A": "Anemia", "B": "Milk-alkali syndrome", "C": "Anorexia nervosa", "D": "Major depressive disorder", "E": "Bulimia nervosa"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A study is performed to determine the prevalence of a particular rare fungal pneumonia. A sample population of 100 subjects is monitored for 4 months. Every month, the entire population is screened and the number of new cases is recorded for the group. The data from the study are given in the table below:\nTime point New cases of fungal pneumonia\nt = 0 months 10\nt = 1 months 4\nt = 2 months 2\nt = 3 months 5\nt = 4 months 4\nWhich of the following is correct regarding the prevalence of this rare genetic condition in this sample population?", "answer": "The prevalence at the conclusion of the study is 25%.", "options": {"A": "The prevalence at time point 2 months is 2%.", "B": "The prevalence at time point 3 months is 11%.", "C": "The prevalence at the conclusion of the study is 15%.", "D": "The prevalence and the incidence at time point 2 months are equal.", "E": "The prevalence at the conclusion of the study is 25%."}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 53-year-old woman comes to the physician because of a 3-year history of increasing weakness of her extremities and neck pain that is worse on coughing or sneezing. She first noticed weakness of her right upper extremity 3 years ago, which progressed to her right lower extremity 2 years ago, her left lower extremity 1 year ago, and her left upper extremity 6 months ago. She has had difficulty swallowing and speaking for the past 5 months. Vital signs are within normal limits. Examination shows an ataxic gait. Speech is dysarthritic. Muscular examination shows spasticity and muscle strength is decreased in all extremities. There is bilateral atrophy of the sternocleidomastoid and trapezius muscles. Deep tendon reflexes are 4+ bilaterally. Plantar response shows an extensor response bilaterally. Sensation is decreased below the C5 dermatome bilaterally. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Foramen magnum meningioma", "options": {"A": "Foramen magnum meningioma", "B": "Cerebellar astrocytoma", "C": "Amyotrophic lateral sclerosis", "D": "Multiple sclerosis", "E": "Cerebral glioblastoma multiforme\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old girl is brought to her pediatrician because of a nosebleed that will not stop. Her parents say that she started having a nosebleed about 1 hour prior to presentation. Since then they have not been able to stop the bleeding. Her past medical history is remarkable for asthma, and she has a cousin who has been diagnosed with hemophilia. Physical exam reveals diffuse petechiae and purpura. A panel of bleeding tests are obtained with the following results:\n\nBleeding time: 11 minutes\nProthrombin time: 14 seconds\nPartial thromboplastin time: 32 seconds\nPlatelet count: 195,000/mm^3\n\nPeripheral blood smear shows normal cell morphology. Which of the following characteristics is most likely true about this patient?", "answer": "Mutation in glycoprotein IIb/IIIa", "options": {"A": "Decreased levels of von Willebrand factor", "B": "Mutation in glycoprotein Ib", "C": "Mutation in glycoprotein IIb/IIIa", "D": "Production of anti platelet antibodies", "E": "Production of antibodies against ADAMTS13"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man presents to his primary care physician with a 2-month history of right upper and lower extremity weakness. He noticed the weakness when he started falling far more frequently while running errands. Since then, he has had increasing difficulty with walking and lifting objects. His past medical history is significant only for well-controlled hypertension, but he says that some members of his family have had musculoskeletal problems. His right upper extremity shows forearm atrophy and depressed reflexes while his right lower extremity is hypertonic with a positive Babinski sign. Which of the following is most likely associated with the cause of this patient's symptoms?", "answer": "Mutation in SOD1", "options": {"A": "HLA-B8 haplotype", "B": "HLA-DR2 haplotype", "C": "Mutation in SOD1", "D": "Mutation in SMN1", "E": "Viral infection"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old African American presents to the emergency department due to abdominal pain, fatigue, and weight loss over the past 3 months. He has a long-standing history of chronic hepatitis B virus infection complicated by cirrhosis. On examination, he has jaundice, leg edema, and a palpable mass in the right upper abdominal quadrant. Abdominal ultrasound shows a 3-cm liver mass with poorly defined margins and coarse, irregular internal echoes. Lab results are shown:\nAspartate aminotransferase (AST) 90 U/L\nAlanine aminotransferase (ALT) 50 U/L\nTotal bilirubin 2 mg/dL\nAlbumin 3 g/dL\nAlkaline phosphatase 100 U/L\nAlpha fetoprotein 600 micrograms/L\nWhich of the following is a feature of this patient's condition?", "answer": "It arises from hepatocytes", "options": {"A": "Liver biopsy is required for diagnosis in a majority of patients", "B": "It arises from the bile duct epithelium", "C": "It arises from hepatocytes", "D": "Daughter cysts are usually present on abdominal ultrasound", "E": "Doppler blood flow shows venous pattern"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 6-year-old boy presents to the office to establish care after recently being assigned to a shelter run by the local child protective services authority. The nurse who performed the vitals and intake says that, when offered an age-appropriate book to read while waiting for the physician, the patient said that he has never attended a school of any sort and is unable to read. He answers questions with short responses and avoids eye contact for most of the visit. His father suffers from alcoholism and physically abused the patient’s mother. Physical examination is negative for any abnormal findings, including signs of fracture or bruising. Which of the following types of abuse has the child most likely experienced?", "answer": "Child neglect", "options": {"A": "Corrupting", "B": "Child neglect", "C": "No abuse", "D": "Active abuse", "E": "Passive abuse"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Researchers are investigating oncogenes, specifically the KRAS gene that is associated with colon, lung, and pancreatic cancer. They have established that the gain-of-function mutation in this gene increases the chance of cancer development. They are also working to advance the research further to study tumor suppressor genes. Which of the genes below is considered a tumor suppressor gene?", "answer": "Rb", "options": {"A": "JAK2", "B": "Her2/neu", "C": "Rb", "D": "BRAF", "E": "BCL-2"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "The success of a new treatment designed to deter people from smoking was evaluated by a team of researchers. However, the heaviest and most committed smokers in the study group were less interested in quitting and subsequently dropped out of the study. Nonetheless, the researchers continued with their research (disregarding those who dropped out), which resulted in a false conclusion that the treatment was more successful than the results would have shown under ideal study conditions. The smokers who were confirmed as quitters were actually the ones who were more interested in giving up smoking, which is why they remained in the study. Which of the following is the bias that invalidates the researchers’ conclusion in this example?", "answer": "Attrition bias", "options": {"A": "Ascertainment bias", "B": "Non-response bias", "C": "Exclusion bias", "D": "Detection bias", "E": "Attrition bias"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old man presents to the emergency department with complaint off dizziness and nausea for the past hour. He says that he can feel his heartbeat racing. He also reports of generalized weakness that began in the morning. He was diagnosed with end-stage renal disease 2 years ago and currently on dialysis, but he missed his last dialysis session. He has also been diabetic for the past 15 years and managed with insulin, and was also diagnosed with celiac disease 8 years ago. He does not smoke or drink alcohol. The family history is insignificant. The temperature is 36.7°C (98.0°F), blood pressure is 145/90 mm Hg, pulse is 87/min, and respiratory rate is 14/min. On physical examination, the patient looks fatigued and exhausted. The muscle strength in the lower limbs is 4/5 bilaterally. An ECG is ordered which shows peaked and narrow T waves and prolongation of PR interval. The lab test results are as follows:\nSerum Sodium 132 mEq/L\nSerum Potassium 8 mEq/L\nSerum Creatinine 5 mg/dL\nBlood urea nitrogen (BUN) 25 mg/dL\nWhat is the mechanism of action of the most likely initial treatment for the patient’s condition?\n ", "answer": "Antagonizes the membrane action of hyperkalemia", "options": {"A": "Blocks Na+/K+ ATPase", "B": "Antagonizes the membrane action of hyperkalemia", "C": "Blocks B adrenergic receptors", "D": "Prevents platelet aggregation", "E": "Increase potassium loss from the gastrointestinal tract"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 38-year-old G1P0 woman presents to her obstetrician for a prenatal visit. She reports feeling well and has no acute concerns. She is currently at 28 weeks gestation previously confirmed by ultrasound. She takes her folate supplements daily. On physical exam, the uterus is soft and globular. The top of the uterine fundus is found around the level of the umbilicus. A fetal ultrasound demonstrates a reduced liver volume and subcutaneous fat with relative sparing of the head. Which of the following is most likely the cause of this patient's ultrasound findings?", "answer": "Cigarette smoking", "options": {"A": "Aneuploidy", "B": "Cigarette smoking", "C": "Fetal congenital heart disease", "D": "Fetal infection", "E": "Neural tube defect"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 7-day-old female newborn is brought to the physician because of lethargy, vomiting, poor feeding, and diarrhea for 4 days. She was born at 39 weeks' gestation. Vital signs are within normal limits. Bilateral cataracts and icterus are present. Examination shows jaundice of the skin, and the liver is palpated 5-cm below the right costal margin. Muscle tone is decreased in all extremities. Serum glucose concentration is 40 mg/dL. Which of the following metabolites is most likely to be increased in this patient?", "answer": "Galactose-1-phosphate", "options": {"A": "Sphingomyelin", "B": "Uric acid", "C": "Branched-chain amino acids", "D": "Galactose-1-phosphate", "E": "Limit dextrins"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 82-year-old man is brought to the emergency department after he was found down by his daughter. On presentation, he is alert and oriented with no obvious signs of trauma. He says that he felt lightheaded shortly before passing out and that he has been feeling extremely fatigued over the last few weeks. He has a known diagnosis of colorectal adenocarcinoma and had it surgically removed 2 months ago; however, recently he has been feeling increasingly short of breath. He has a 60-pack-year smoking history and drinks 2-3 beers a night. He worked as an insulation technician and shipyard laborer for 40 years prior to retiring at age 65. Radiographs reveal approximately a dozen new nodules scattered throughout his lungs bilaterally. Biopsy of these lesions would most likely reveal which of the following?", "answer": "Mucin-producing glands with squamous components", "options": {"A": "Flat cells with keratin pearls and intercellular bridges", "B": "Mucin-producing glands with squamous components", "C": "Pleomorphic giant cells", "D": "Psammoma bodies", "E": "Small dark blue cells that stain for chromogranin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old woman comes to the physician because of lower back pain, night sweats, and a 5-kg (11-lb) weight loss during the past 4 weeks. She has rheumatoid arthritis treated with adalimumab. Her temperature is 38°C (100.4°F). Physical examination shows tenderness over the T10 and L1 spinous processes. Passive extension of the right hip causes pain in the right lower quadrant. The patient's symptoms are most likely caused by an organism with which of the following virulence factors?", "answer": "Surface glycolipids that prevent phagolysosome fusion", "options": {"A": "Polysaccharide capsule that prevents phagocytosis", "B": "Surface glycolipids that prevent phagolysosome fusion", "C": "Polypeptides that inactivate elongation factor 2", "D": "Proteins that bind to the Fc region of immunoglobulin G", "E": "Protease that cleaves immunoglobulin A"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old woman presents to her primary care physician for a wellness visit. She states she is generally healthy and currently has no complaints. She drinks 1 alcoholic beverage daily and is currently sexually active. Her last menstrual period was 1 week ago and it is regular. She smokes 1 pack of cigarettes per day and would like to quit. She describes her mood as being a bit down in the winter months but otherwise feels well. Her family history is notable for diabetes in all of her uncles and colon cancer in her mother and father at age 72 and 81, respectively. She has been trying to lose weight and requests help with this as well. Her diet consists of mostly packaged foods. His temperature is 98.0°F (36.7°C), blood pressure is 122/82 mmHg, pulse is 80/min, respirations are 12/min, and oxygen saturation is 98% on room air. Her BMI is 23 kg/m^2. Physical exam reveals a healthy woman with no abnormal findings. Which of the following is the most appropriate initial intervention for this patient?", "answer": "Varenicline and nicotine gum", "options": {"A": "Alcohol cessation", "B": "Bupropion", "C": "Colonoscopy", "D": "Varenicline and nicotine gum", "E": "Weight loss, exercise, and nutrition consultation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old male presents to his primary care physician complaining of right hip pain for the past eight months. He also reports progressive loss of hearing over the same time period. Radiographic imaging reveals multiple areas of expanded bony cortices and coarsened trabeculae in his right hip and skull. Laboratory analysis reveals an isolated elevation in alkaline phosphatase with normal levels of serum calcium and phosphate. Which of the following histologic findings is most likely to be seen if one of the lesions were biopsied?", "answer": "Immature woven bone with collagen fibers arranged irregularly", "options": {"A": "Immature woven bone with collagen fibers arranged irregularly", "B": "Mature lamellar bone with collagen fibers arranged in lamellae", "C": "Chondroblasts and chondrocytes forming a cartilaginous matrix", "D": "Large pleomorphic cells with numerous atypical mitotic figures and “lacey” osteoid formation", "E": "Sheets of monotonous round blue cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman comes to the physician because she has not had a menstrual period for 3 months. Menarche occurred at the age of 12 years and menses occurred at regular 30-day intervals until they became irregular 1 year ago. She is 160 cm (5 ft 3 in) tall and weighs 85 kg (187 lb); BMI is 33.2 kg/m2. Physical exam shows nodules and pustules along the jaw line and dark hair growth around the umbilicus. Pelvic examination shows a normal-sized, retroverted uterus. A urine pregnancy test is negative. Without treatment, this patient is at greatest risk for which of the following?", "answer": "Endometrial carcinoma", "options": {"A": "Endometrioma", "B": "Cervical carcinoma", "C": "Choriocarcinoma", "D": "Mature cystic teratoma", "E": "Endometrial carcinoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old woman with Crohn’s disease colitis presents to her physician after 2 days of photophobia and blurred vision. She has had no similar episodes in the past. She has no abdominal pain or diarrhea and takes mesalazine, azathioprine, and prednisone as maintenance therapy. Her vital signs are within normal range. Examination of the eyes shows conjunctival injection. The physical examination is otherwise normal. Slit-lamp examination by an ophthalmologist shows evidence of inflammation in the anterior chamber. Which of the following is the most appropriate modification to this patient’s medication at this time?", "answer": "Increasing dose of prednisone", "options": {"A": "Adding infliximab", "B": "Decreasing dose of azathioprine", "C": "Discontinuing sulfasalazine", "D": "Increasing dose of prednisone", "E": "No modification of therapy at this time"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old woman with type 2 diabetes mellitus is admitted to the hospital because of a 2-day history of fever, breathlessness, and cough productive of large quantities of green sputum. She drinks 8 beers daily. Her temperature is 39°C (102.2°F), pulse is 110/min, respirations are 28/min, and blood pressure is 100/60 mm Hg. Blood and sputum cultures grow gram-negative, catalase-positive, capsulated bacilli. Which of the following components of the causal organism is the most likely cause of this patient's hypotension?", "answer": "Lipid A", "options": {"A": "Lecithinase", "B": "Lipooligosaccharide", "C": "Poly-D-glutamate", "D": "Teichoic acid", "E": "Lipid A"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-month-old male presents for a routine visit to his pediatrician. Two months ago, the patient was seen for tachypnea and wheezing, and diagnosed with severe respiratory syncytial virus (RSV) bronchiolitis. After admission to the hospital and supportive care, the patient recovered and currently is not experiencing any trouble breathing. Regarding the possible of future reactive airway disease, which of the following statements is most accurate?", "answer": "“Your child has a greater than 20% chance of developing asthma”", "options": {"A": "“Your child’s risk of asthma is the same as the general population.”", "B": "“There is no clear relationship between RSV and the development of asthma.”", "C": "“Your child has a less than 5% chance of developing asthma”", "D": "“Your child has a greater than 20% chance of developing asthma”", "E": "“Your child’s risk of asthma is less than the general population.”"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 12-year-old boy is brought to an outpatient clinic by his mother, who noticed that her son’s urine has been dark for the past 4 days. She initially attributed this to inadequate hydration, so she monitored her son’s fluid intake and encouraged him to drink more water. However, she noticed that the color of the urine kept getting darker until it began to resemble cola. The boy’s medical history is significant for a sore throat approx. 2 weeks ago, which resolved without medication or treatment. The boy has also been complaining of pain in his ankles, which he first noticed shortly after soccer practice 1 week ago. He has had no pain during urination or urethral discharge, however, and does not have any history of previous episodes of cola-colored urine or passage of blood in the urine. However, the boy has been experiencing intermittent episodes of abdominal pain for the past 3 days. The boy also has wheals on his torso, legs, and buttocks, which his mother attributes to seasonal allergies. Physical examination reveals an alert child who is not in obvious distress but who has a mild conjunctival pallor. Vital signs include: respiratory rate is 22/min, temperature is 36.7°C (98.0°F), and blood pressure is 130/90 mm Hg. Examination of the musculoskeletal system reveals multiple skin lesions (see image). Which of the following laboratory findings is most likely associated with this patient’s clinical presentation?", "answer": "Elevated level of serum IgA", "options": {"A": "24-hour urinary protein of more than 4 g", "B": "Low C-reactive protein level", "C": "Elevated level of serum IgA", "D": "Elevated IgM-IgG immune complex rheumatoid factor", "E": "Elevated levels of serum IgG and C3 protein"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 7-month-old boy is brought to the ED by his mother because of abdominal pain. Two weeks ago, she noticed he had a fever and looser stools, but both resolved after a few days. One week ago, he began to experience periodic episodes during which he would curl up into a ball, scream, and cry. The episodes lasted a few minutes, and were occasionally followed by vomiting. Between events, he was completely normal. She says the episodes have become more frequent over time, and this morning, she noticed blood in his diaper. In the ED, his vitals are within normal ranges, and his physical exam is normal. After confirming the diagnosis with an abdominal ultrasound, what is the next step in management?", "answer": "Air contrast enema", "options": {"A": "Supportive care", "B": "Air contrast enema", "C": "Abdominal laparotomy", "D": "Abdominal CT scan", "E": "Broad-spectrum antibiotics"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old man visits a local clinic while volunteering abroad to rebuild homes after a natural disaster. He reports that he has been experiencing an intermittent rash on his feet for several weeks that is associated with occasional itching and burning. He states that he has been working in wet conditions in work boots and often does not get a chance to remove them until just before going to bed. On physical exam, there is diffuse erythema and maceration of the webspaces between his toes. He starts taking a medication. Two days later, he experiences severe nausea and vomiting after drinking alcohol. Which of the following is the mechanism of action of the drug most likely prescribed in this case?", "answer": "Cell arrest at metaphase", "options": {"A": "Cell arrest at metaphase", "B": "Disruption of fungal cell membrane", "C": "Inhibition of cell wall synthesis", "D": "Inhibition of DNA synthesis", "E": "Inhibition of steroid synthesis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 58-year-old male presents to his primary care doctor with the complaint of vision changes over the last several months. The patient's past medical history is notable for schizophrenia which has been well-controlled for the last 25 years on chlorpromazine. Which of the following is likely to be seen on ophthalmoscopy?", "answer": "Corneal deposits", "options": {"A": "Retinitis pigmentosa", "B": "Macular degeneration", "C": "Glaucoma", "D": "Retinal hemorrhage", "E": "Corneal deposits"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old woman presents with a ‘tingling’ feeling in the toes of both feet that started 5 days ago. She says that the feeling varies in intensity but has been there ever since she recovered from a stomach flu last week. Over the last 2 days, the tingling sensation has started to spread up her legs. She also reports feeling weak in the legs for the past 2 days. Her past medical history is unremarkable, and she currently takes no medications. Which of the following diagnostic tests would most likely be abnormal in this patient?", "answer": "Nerve conduction studies", "options": {"A": "Noncontrast CT of the head", "B": "Transthoracic echocardiography", "C": "Serum hemoglobin concentration", "D": "Nerve conduction studies", "E": "Serum calcium concentration"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "А 60-уеаr-old Ніѕраnіс mаn рrеѕеntѕ to thе offісе for а rеgulаr hеаlth сhесkuр. Не hаѕ bееn wаіtіng for his hір rерlасеmеnt ѕurgеrу for osteoarthritis, whісh he was diagnosed for the past 5 уеаrѕ. Не admits to having taken high doses of painkillers for hip pain management, but now they don’t provide any pain relief. Ніѕ vіtаl ѕigns include: blood рrеѕѕurе 110/70 mm Нg, рulѕе 78/mіn, tеmреrаturе 36.7°C (98.1°F), and rеѕріrаtorу rаtе 10/mіn. Оn physical ехаmіnаtіon, thеrе іѕ а lіmіtеd rаngе of motіon of hіѕ rіght hір.\nThe laboratory results are as follows:\nHemoglobin 12 g/dL\nRed blood cell 5.1 million cells/µL\nHematocrit 45%\nTotal leukocyte count 6,500 cells/µL\nNeutrophils 71%\nLymphocyte 14%\nMonocytes 4%\nEosinophil 11%\nBasophils 0%\nPlatelets 240,000 cells/µL\nUrinalysis shows:\npH 6.2\nColor light yellow\nRBC 7–8/ HPF\nWBC 10-12 /HPF\nProtein 1+\nCast none\nGlucose absent\nCrystal none\nKetone absent\nNitrite negative\n24-hr urine protein excretion 0.9 g\nUrine for culture No growth noted after 48 hours of inoculation at 37.0°C (98.6°F)\nWhat is the most likely diagnosis?", "answer": "Analgesic nephropathy", "options": {"A": "Chronic pyelonephritis", "B": "Diffuse cortical necrosis", "C": "Acute tubular necrosis", "D": "Membranous nephropathy", "E": "Analgesic nephropathy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman is hospitalized due to depression and suicidal ideation. She has a 5-year history of chaotic relationships that last only a few short weeks or months. Each relationship has left her feeling abandoned, empty, and extremely upset. During these periods, the patient confesses to shopping and making big purchases on impulse. She says she gets bored easily and moves on to the next adventure. The patient denies any changes in appetite, energy level, or concentration. On examination, multiple linear lacerations of varying phases of healing were noted on her forearms and trunk. Following consultation, she praises physicians to be ‘the best people on the planet’, but when the nurse came in to take her blood, she furiously stated that ‘all nurses are incompetent and cruel’. Which of the following is the most likely diagnosis?", "answer": "Borderline personality disorder", "options": {"A": "Major depressive disorder (MDD)", "B": "Bipolar I disorder", "C": "Borderline personality disorder", "D": "Histrionic personality disorder", "E": "Factitious disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 63-year-old man is brought to the emergency department by his wife because she is concerned he is having another stroke. The patient says he woke up with right-sided facial weakness and drooping. Past medical history is significant for a recent case of shingles treated with acyclovir, and a stroke, diagnosed 10 years ago, from which he recovered with no residual functional deficits. On physical examination, there is weakness and drooping of the entire right side of the face. Sensation is intact. The remainder of the physical examination is unremarkable. Which of the following additional findings would also most likely be seen in this patient?", "answer": "Decreased salivation", "options": {"A": "Decreased salivation", "B": "Partial hearing loss", "C": "Complete loss of taste to the tongue", "D": "Wrinkled forehead", "E": "Expressive aphasia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old male with diffuse large B cell lymphoma is treated with a chemotherapy regimen including 6-mercaptopurine. Administration of which of the following agents would increase this patient’s risk for mercaptopurine toxicity?", "answer": "Allopurinol", "options": {"A": "Leucovorin", "B": "Dexrazoxane", "C": "Mesna", "D": "Allopurinol", "E": "Amifostine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man comes to the physician because of weight loss and increased urinary frequency for the past month. He has also noticed blood in the urine, usually towards the end of voiding. He emigrated to the U.S. from Kenya 5 years ago. He has smoked one pack of cigarettes daily for 35 years. Physical examination shows a palpable liver edge and splenomegaly. Laboratory studies show a hemoglobin concentration of 9.5 mg/dL and a urine dipstick is strongly positive for blood. A CT scan of the abdomen shows bladder wall thickening and fibrosis. A biopsy specimen of the bladder shows squamous cell carcinoma. Which of the following additional findings is most likely in this patient?", "answer": "Elevated mean pulmonary artery pressure", "options": {"A": "Calcified cysts in the liver", "B": "Dilation of right and left ventricles", "C": "Elevated mean pulmonary artery pressure", "D": "Atrophy of the retina with sclerosing keratitis", "E": "Peripheral nonpitting edema"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old woman is brought to the emergency department because of sudden loss of vision in her right eye that occurred 50 minutes ago. She does not have eye pain. She had several episodes of loss of vision in the past, but her vision improved following treatment with glucocorticoids. She has coronary artery disease, hypertension, type 2 diabetes mellitus, and multiple sclerosis. She underwent a left carotid endarterectomy 3 years ago. She had a myocardial infarction 5 years ago. Current medications include aspirin, metoprolol, lisinopril, atorvastatin, metformin, glipizide, and weekly intramuscular beta-interferon injections. Her temperature is 36.8°C (98.2°F), pulse is 80/min, and blood pressure is 155/88 mm Hg. Examination shows 20/50 vision in the left eye and no perception of light in the right eye. The direct pupillary reflex is brisk in the left eye and absent in the right eye. The indirect pupillary reflex is brisk in the right eye but absent in the left eye. Intraocular pressure is 18 mm Hg in the right eye and 16 mm Hg in the left eye. A white, 1-mm ring is seen around the circumference of the cornea in both eyes. Fundoscopic examination of the right eye shows a pale, white retina with a bright red area within the macula. The optic disc appears normal. Fundoscopic examination of the left eye shows a few soft and hard exudates in the superior and nasal retinal quadrants. The optic disc and macula appear normal. Which of the following is the most likely diagnosis?", "answer": "Central retinal artery occlusion", "options": {"A": "Central serous retinopathy", "B": "Acute angle-closure glaucoma", "C": "Central retinal vein occlusion", "D": "Vitreous hemorrhage", "E": "Central retinal artery occlusion"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A male child is presented at the pediatric clinic for a well-child visit by his mother who reports previously normal developmental milestones. The child was born at 40 weeks with no complications during pregnancy or birth. The mother notes that the child is able to sit momentarily propped up with his hand. The infant is able to sit without support. He is able to feed himself crackers and pureed food. He is constantly shaking his toy teddy bear but is able to stop when the mother says ‘no’. Which of the following indicate the most likely language milestone the child presents with?", "answer": "Babbling", "options": {"A": "Able to say his first and last name", "B": "Babbling", "C": "Cooing", "D": "Saying words such as apple and cat, though limited to around 4 different words", "E": "Two-word combinations"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 14-year-old boy is brought to a child psychiatry office by his father, who is concerned about his grades and teachers’ comments that he has “problems focusing.” He has a B- average. The boy's teachers in math, social studies, and English say that he often appears to not be listening in class, instead talking to classmates, making jokes, and blurting out incorrect answers. He typically turns in his homework late or not at all. During other classes (band and science, which he enjoys), none of these behaviors are observed. At home, he enjoys playing chess and reads comic and fiction books for hours without pause. His father describes him as calm and organized at home. Formal testing reveals an intelligence quotient (IQ) of 102. Which of the following is the most likely explanation for this patient’s grades?", "answer": "Reduced interest", "options": {"A": "Absence seizures", "B": "Attention deficit hyperactivity disorder (ADHD)", "C": "Intellectual disability", "D": "Mood disorder", "E": "Reduced interest"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old male who is being treated for depression visits your emergency room complaining of being unable to urinate. In addition, the patient complains of tachycardia and dry mouth. He has no history of benign prostatic hyperplasia and reports of only being on one psychiatric medication. What type of psychiatric medication would cause such a side effect profile?", "answer": "Tricyclic antidepressant", "options": {"A": "Monoamine oxidase inhibitor", "B": "Serotonin norepinephrine receptor inhibitor", "C": "Aminoketone", "D": "Selective serotonin reuptake inhibitor", "E": "Tricyclic antidepressant"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 5-year-old boy is brought to the emergency department because of a 1-day history of high fever. His temperature prior to arrival was 40.0°C (104°F). There is no family history of serious illness. Development has been appropriate for his age. He is administered rectal acetaminophen. While in the waiting room, he becomes unresponsive and starts jerking his arms and legs back and forth. A fingerstick blood glucose concentration is 86 mg/dL. After 5 minutes, he continues having jerky movements and is unresponsive to verbal and painful stimuli. Which of the following is the most appropriate next step in management?", "answer": "Intravenous administration of lorazepam", "options": {"A": "Intravenous administration of valproate", "B": "Intravenous administration of lorazepam", "C": "Intravenous administration of phenobarbital", "D": "Obtain blood cultures", "E": "Intravenous administration of fosphenytoin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 21-year-old man with a recent history of traumatic right femur fracture status post open reduction and internal fixation presents for follow-up. The patient says his pain is controlled with the oxycodone but he says he has been severely constipated the past 4 days. No other past medical history. Current medications are oxycodone and ibuprofen. The patient is afebrile and vital signs are within normal limits. On physical examination, surgical incision is healing well. Which of the following is correct regarding the likely role of opiates in this patient’s constipation?", "answer": "Opiates increase fluid absorption from the lumen leading to hard stools", "options": {"A": "Opiates cause rapid gastrointestinal transit", "B": "Opiates increase the production and secretion of pancreatic digestive enzymes", "C": "Opiates increase fluid absorption from the lumen leading to hard stools", "D": "Opiates decrease the sympathetic activity of the gut wall", "E": "Opiates activate the excitatory neural pathways in the gut"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old man presents to an urgent care center with epigastric discomfort following meals and an occasional dry cough worse in the morning, both of which have increased in frequency over the past several months. He is otherwise healthy and has no additional complaints. Past medical history is significant for major depressive disease, anxiety, and hypothyroidism. Physical exam is unremarkable. Given the following options, what is the most appropriate next step in patient management?", "answer": "Lifestyle modifications", "options": {"A": "Electrocardiogram", "B": "Lifestyle modifications", "C": "Begin Omeprazole therapy", "D": "EGD with esophageal biopsy", "E": "Fluoroscopic barium swallow"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 66-year-old man comes to the physician because of a 3-month history of constipation and streaks of blood in his stool. He has had a 10-kg (22-lb) weight loss during this period. Colonoscopy shows an exophytic tumor in the sigmoid colon. A CT scan of the abdomen shows liver metastases and enlarged mesenteric and para-aortic lymph nodes. A diagnosis of stage IV colorectal cancer is made, and palliative chemotherapy is initiated. The chemotherapy regimen includes a monoclonal antibody that inhibits tumor growth by preventing ligand binding to a protein directly responsible for epithelial cell proliferation and organogenesis. Which of the following proteins is most likely inhibited by this drug?", "answer": "EGFR", "options": {"A": "ALK", "B": "EGFR", "C": "TNF-α", "D": "VEGF", "E": "CD52"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 9-year-old girl is brought to the physician because her parents are concerned about their daughter's physical changes. She recently started wearing a bra and uses a facial scrub for oily skin. The parents have also noticed increasing body odor. The patient has a history of migraine headaches controlled with propranolol. She is at the 55th percentile for height and 60th percentile for weight. Examination shows separation of areola and breast contours; the nipple and areola form a secondary mound. Coarse dark axillary hair and sparse pubic hair are present. Which of the following is the most likely cause of these findings?", "answer": "Physiological development", "options": {"A": "Tumor of the pineal gland", "B": "Hamartoma of the hypothalamus", "C": "Physiological development", "D": "Mosaic G-protein mutation", "E": "Functioning follicular ovarian cyst"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 31-year-old woman presents to her gynecologist to be evaluated for her inability to conceive. She is G1P0 who has a 28-day cycle and no menstrual abnormalities. Her single pregnancy terminated early with an elective abortion at the patient’s request. She had several sexual partners before meeting her husband 5 years ago. They have intercourse regularly without the use of contraception and have been tracking her ovulation cycle to try to become pregnant for at least 1 year. She reports a history of occasional malodorous vaginal discharge and mild lower abdominal pain after menses and sexual intercourse, but she notes no such symptoms recently. Her husband’s spermogram was normal. Her weight is 65 kg (143 lb) and the height is 160 cm (5 ft, 3 in). On examination, the patient’s vital signs are within normal limits. The physical examination is unremarkable. On pelvic examination, the adnexa are slightly tender to palpation bilaterally. Which of the following tests is the most reasonable to be performed next in this patient?", "answer": "Hysterosalpingography", "options": {"A": "Post-coital testing of cervical mucus", "B": "Test for anti-Mullerian hormone", "C": "Exploratory laparoscopy", "D": "Hysterosalpingography", "E": "Pelvic MRI"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 10-day-old male infant is brought to the emergency room for abdominal distension for the past day. His mother reports that he has been refusing feeds for about 1 day and appears more lethargic than usual. While changing his diaper today, she noticed that the baby felt warm. He has about 1-2 wet diapers a day and has 1-2 seedy stools a day. The mother reports an uncomplicated vaginal delivery. His past medical history is significant for moderate respiratory distress following birth that has since resolved. His temperature is 101°F (38.3°C), blood pressure is 98/69 mmHg, pulse is 174/min, respirations are 47/min, and oxygen saturation is 99% on room air. A physical examination demonstrates a baby in moderate distress with abdominal distension. What is the best initial step in the management of this patient?", "answer": "Urinary catheterization", "options": {"A": "Cystoscopy", "B": "Radionuclide scan", "C": "Renal ultrasound", "D": "Urinary catheterization", "E": "Voiding cystourethrogram"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 66-year-old male with a history of deep venous thrombosis is admitted to the hospital with shortness of breath and pleuritic chest pain. He is treated with an anticoagulant, but he develops significant hematochezia. His BP is now 105/60 and HR is 117; both were within normal limits on admission. The effects of the anticoagulant are virtually completely reversed with the administration of protamine. Which of the following was the anticoagulant most likely administered to this patient?", "answer": "Heparin", "options": {"A": "Warfarin", "B": "Enoxaparin", "C": "Heparin", "D": "Bivalirudin", "E": "Dabigatran"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-day-old boy is brought to the physician because of somnolence, poor feeding, and vomiting after his first few breast feedings. He appears lethargic. His respiratory rate is 73/min. Serum ammonia is markedly increased. Genetic analysis shows deficiency in N-acetylglutamate synthase. The activity of which of the following enzymes is most likely directly affected by this genetic defect?", "answer": "Carbamoyl phosphate synthetase I", "options": {"A": "Carbamoyl phosphate synthetase I", "B": "Ornithine translocase", "C": "Argininosuccinate synthetase", "D": "Argininosuccinase", "E": "Arginase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "During the selection of subjects for a study on infantile vitamin deficiencies, a child is examined by the lead investigator. She is at the 75th percentile for head circumference and the 80th percentile for length and weight. She can lift her chest and shoulders up when in a prone position, but cannot roll over from a prone position. Her eyes follow objects past the midline. She coos and makes gurgling sounds. When the investigator strokes the sole of her foot, her big toe curls upward and there is fanning of her other toes. She makes a stepping motion when she is held upright and her feet are in contact with the examination table. Which of the following additional skills or behaviors would be expected in a healthy patient of this developmental age?", "answer": "Smiles at her mother", "options": {"A": "Reaches out for objects", "B": "Responds to calling of own name", "C": "Cries when separated from her mother", "D": "Rolls over from her back", "E": "Smiles at her mother"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Two viruses, X and Y, infect the same cell and begin to reproduce within the cell. As a result of the co-infection, some viruses are produced where the genome of Y is surrounded by the nucleocapsid of X and vice versa with the genome of X and nucleocapsid of Y. When the virus containing genome X surrounded by the nucleocapsid of Y infects another cell, what is the most likely outcome?", "answer": "Virions containing genome X and nucleocapsid X will be produced", "options": {"A": "Virions containing genome X and nucleocapsid Y will be produced", "B": "Virions containing genome X and nucleocapsid X will be produced", "C": "Virions containing genome Y and nucleocapsid Y will be produced", "D": "Virions containing genome Y and nucleocapsid X will be produced", "E": "No virions will be produced"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old Caucasian male presents to the clinic to establish care. He has never seen a physician and denies any known medical problems. Physical examination is notable for central obesity, but the patient has regular heart and lung sounds. He has a blood pressure of 157/95 mm Hg and heart rate of 92/min. He follows up 2 weeks later, and his blood pressure continues to be elevated. At this time, you diagnose him with essential hypertension and decide to initiate antihypertensive therapy. Per the Joint National Committee 8 guidelines for treatment of high blood pressure, of the following combinations of drugs, which can be considered for first-line treatment of high blood pressure in the Caucasian population?", "answer": "ACE inhibitor, ARB, CCB, or thiazide", "options": {"A": "ACE inhibitor, angiotensin receptor blocker (ARB), beta-blocker (BB), or thiazide", "B": "ACE inhibitor, ARB, CCB, or thiazide", "C": "ACE inhibitor, ARB, CCB or loop diuretic", "D": "ACE inhibitor, ARB, alpha-blocker, or loop diuretic", "E": "ACE inhibitor, ARB, alpha-blocker, or direct vasodilator"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 50-year-old woman returns from a family trip to the Caribbean with three days of fever, watery diarrhea, and vomiting. She states that she tried to avoid uncooked food and unpeeled fruits on her vacation. Of note, her grandson had caught a cold from daycare prior to the trip, and she had been in close contact with the infant throughout the trip. She denies rhinorrhea or coughing. On exam, her temperature is 99.1°F (37.3°C), blood pressure is 110/68 mmHg, pulse is 113/min, and respirations are 12/min. Her stool culture is negative for bacteria. Which of the following describes the most likely cause?", "answer": "(+) ssRNA virus", "options": {"A": "Linear dsDNA virus", "B": "Linear dsRNA virus", "C": "ssDNA virus", "D": "(+) ssRNA virus", "E": "(-) ssRNA virus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-year-old high school student is brought to the emergency department after collapsing during her cheerleading practice session. She was brought to the hospital even though she regained consciousness within seconds. Her mother informs the doctor that she had a similar episode last month at a party, but they thought it was due to stress and exhaustion. Both incidents occurred in a loud and crowded environment. Her past medical history is insignificant. Her blood pressure is 120/80 mm Hg and the pulse is 77/min and regular. Physical examination findings are within normal limits. A set of tests are ordered along with a 12-lead ECG. The ECG tracing obtained is shown. What is the best treatment option for this patient?", "answer": "Nadolol", "options": {"A": "Epinephrine", "B": "Erythromycin", "C": "Furosemide", "D": "Nadolol", "E": "Quinidine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old man comes to the physician because of severe muscle aches and fatigue for 3 days. Last week he was diagnosed with atypical pneumonia and treated with clarithromycin. He has hyperlipidemia for which he takes lovastatin. Physical examination shows generalized tenderness of the proximal muscles in the upper and lower extremities. Serum studies show an elevated creatinine kinase concentration. This patient's current symptoms are most likely caused by inhibition of which of the following hepatic enzymes?", "answer": "CYP3A4", "options": {"A": "CYP2E1", "B": "CYP3A4", "C": "CYP2C9", "D": "CYP1A2", "E": "CYP2C19"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old woman presents to the physician for a routine health maintenance examination. She has a history of dyslipidemia and chronic hypertension. Her medications include atorvastatin, hydrochlorothiazide, and lisinopril. She exercises every day and follows a healthy diet. She does not smoke. There is no family history of chronic disease. Her blood pressure is 130/80 mm Hg, which is confirmed on repeat measurement. Her BMI is 22 kg/m2. The physical examination shows no abnormal findings. The laboratory test results show:\nSerum  \nTotal cholesterol 193 mg/dL\nLow-density lipoprotein (LDL-C) 124 mg/dL\nHigh-density lipoprotein (HDL-C) 40 mg/dL\nTriglycerides 148 mg/dL\nThe patient's 10-year risk of cardiovascular disease (CVD) is 4.6%. Which of the following is the most appropriate next step in pharmacotherapy?", "answer": "Ezetimibe", "options": {"A": "Ezetimibe", "B": "Fenofibrate", "C": "Niacin", "D": "Fish oils", "E": "No additional pharmacotherapy at this time"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 30-year-old woman presents to her new doctor at 27 weeks' gestation with her second pregnancy. Her blood type is B- and the father of the child is B+. Her first child had an Apgar score of 7 at 1 minute and 9 at 5 minutes and has a B+ blood type. The fetus has a heart rate of 130/min and blood pressure of 100/58 mm Hg. There is a concern that the fetus may develop erythroblastosis fetalis (EF). Which of the following statements is true about erythroblastosis fetalis?", "answer": "Can occur with an Rh-negative mother and Rh-positive father.", "options": {"A": "Can occur with an Rh-negative mother and Rh-positive father.", "B": "Rho(D) immune globulin should be administered during the first trimester.", "C": "The first child will always be affected, as well as all subsequent pregnancies.", "D": "The combination of an Rh-positive mother and an Rh-negative fetus will cause the condition.", "E": "In EF, IgM crosses the placenta and causes erythrocyte hemolysis in the fetus."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Five days after undergoing right hemicolectomy for colon cancer, a 62-year-old man has fever, abdominal pain, nausea, and urinary frequency. The surgery was uncomplicated. An indwelling urinary catheter was placed intraoperatively. His temperature is 39.4°C (102.9°F), pulse is 91/min, and blood pressure is 118/83 mm Hg. There is tenderness to palpation of the costovertebral angle. The urine collected in the catheter bag appears cloudy. Which of the following measures is most likely to have prevented this patient's current condition?", "answer": "Early removal of catheter", "options": {"A": "Urinary antiseptics", "B": "Early removal of catheter", "C": "Antimicrobial prophylaxis", "D": "Periurethral care", "E": "Daily catheter replacement"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 42-year-old man comes to the emergency room with constipation and diffuse, worsening abdominal pain for 2 days. He has no history of major medical illness. His father died in a car accident at the age of 32 years, and his mother has type 2 diabetes mellitus. A diagnosis of bowel obstruction is suspected and he is taken to the operating room for exploratory laparotomy. A partial resection of the colon is performed. The gross appearance of the patient's colonic tissue is shown. Microscopic examination shows tubular, tubulovillous, and villous adenomas. Assuming the patient's partner is not a carrier of the condition, which of the following is the likelihood that this patient’s children will develop this condition?", "answer": "50%", "options": {"A": "100%", "B": "25%", "C": "75%", "D": "50%", "E": "0%"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old man is brought to the emergency department by his wife with a 2-hour history of diarrhea and vomiting. He says that he felt fine in the morning, but noticed that he was salivating, sweating, and feeling nauseated on the way home from his work as a landscaper. The diarrhea and vomiting then started about 10 minutes after he got home. His past medical history is significant for depression and drug abuse. His wife says that he has also been more confused lately and is afraid he may have ingested something unusual. Physical exam reveals miosis, rhinorrhea, wheezing, and tongue fasciculations. Which of the following treatments would most likely be effective for this patient?", "answer": "Atropine", "options": {"A": "Ammonium chloride", "B": "Atropine", "C": "Fomepizole", "D": "Naloxone", "E": "Sodium bicarbonate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old female presents to clinic inquiring about the meaning of a previous negative test result from a new HIV screening test. The efficacy of this new screening test for HIV has been assessed by comparison against existing gold standard detection of HIV RNA via PCR. The study includes 1000 patients, with 850 HIV-negative patients (by PCR) receiving a negative test result, 30 HIV-negative patients receiving a positive test result, 100 HIV positive patients receiving a positive test result, and 20 HIV positive patients receiving a negative test result. Which of the following is most likely to increase the negative predictive value for this test?", "answer": "Decreased prevalence of HIV in the tested population", "options": {"A": "Increased prevalence of HIV in the tested population", "B": "Decreased prevalence of HIV in the tested population", "C": "Increased number of false positive test results", "D": "Increased number of false negative test results", "E": "Decreased number of false positive test results"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old woman is brought to the emergency room by her husband complaining, “I can’t see out of my right eye.” She was watching television last night when she covered her left eye due to an itch and discovered that she could not see. The patient denies any precipitating event, pain, swelling, flashes, floaters, or headaches. Her past medical history is significant for uncontrolled hypertension and angina. Her medications include hydrochlorothiazide, lisinopril, atorvastatin, and nitroglycerin as needed. Her physical examination is unremarkable. Fundus examination demonstrates generalized pallor and slight disc edema with no hemorrhages. What is the most likely explanation for this patient’s symptoms?", "answer": "Occlusion of the ophthalmic artery by embolus", "options": {"A": "Acute increase in pressure of the eye", "B": "Detachment of the retina", "C": "Inflammation of the temporal artery", "D": "Occlusion of the ophthalmic artery by embolus", "E": "Optic neuritis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old man is brought to the emergency department with shortness of breath and chest pain, 35 minutes after he was involved in a high-speed motor vehicle collision. He was the helmeted driver of a scooter hit by a truck. On arrival, he is alert and oriented with a Glasgow Coma Scale rating of 14. His temperature is 37.3°C (99.1°F), pulse is 103/min, respirations are 33/min and blood pressure is 132/88 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 94%. Examination shows multiple abrasions over his abdomen and extremities. There is a 2.5-cm (1-in) laceration on the left side of the chest. There are decreased breath sounds over the left base. Cardiac examination shows no abnormalities. The abdomen is soft and there is tenderness to palpation over the left upper quadrant. Bowel sounds are normal. His hemoglobin concentration is 13.6 g/dL, leukocyte count is 9,110/mm3, and platelet count is 190,000/mm3. A chest x-ray is shown. Which of the following is the most likely diagnosis?", "answer": "Diaphragmatic rupture", "options": {"A": "Diaphragmatic rupture", "B": "Esophageal perforation", "C": "Diaphragmatic eventration", "D": "Pneumothorax", "E": "Phrenic nerve palsy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 72-year-old man has been recently diagnosed with stage 3 squamous cell carcinoma of the oral cavity. After the necessary laboratory workup, concurrent chemoradiation therapy has been planned. Radiation therapy is planned to take place over 7 weeks and he will receive radiation doses daily, Monday–Friday, in 2.0 Gy fractions. For concurrent chemotherapy, he will receive intravenous cisplatin at a dosage of 50 mg/m2 weekly for 7 weeks. Which of the following best explains the mechanism of action of the antineoplastic drug that the patient will receive?", "answer": "Formation of interstrand DNA cross-links", "options": {"A": "Inhibition of polymerization of tubulin", "B": "Inhibition of topoisomerase 2", "C": "Formation of interstrand DNA cross-links", "D": "Inhibition of topoisomerase 1", "E": "Free radical-mediated lipid peroxidation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old woman presents to her primary care provider with shortness of breath. She reports a 3-month history of difficulty breathing with exertion that has progressed to affect her at rest. She swims 45 minutes every day but has had trouble swimming recently due to her breathing difficulties. Her past medical history is notable for well-controlled mild intermittent asthma and generalized anxiety disorder. She has a 15 pack-year smoking history but quit 15 years ago. She does not drink alcohol. Her mother died at the age of 60 from heart failure and was a lifetime non-smoker. Her temperature is 99°F (37.2°C), blood pressure is 135/85 mmHg, pulse is 85/min, and respirations are 22/min. Her BMI is 23 kg/m^2. On exam, she has slightly increased work of breathing. Cardiac auscultation reveals a normal S1 and loud P2. An echocardiogram is performed demonstrating right ventricular hypertrophy. Her pulmonary artery pressure is 24 mmHg at rest and 40 mmHg with exercise. This patient’s condition is associated with a mutation in a gene that does which of the following?", "answer": "Inhibits smooth muscle proliferation", "options": {"A": "Degrades proteases", "B": "Inhibits free radical formation", "C": "Inhibits smooth muscle proliferation", "D": "Internalizes low-density lipoprotein", "E": "Promotes intracellular chloride transport"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 20-year-old man presents to the family medicine clinic with left knee pain. He is the star running back for his college football team with a promising future in the sport. He states he injured his knee 2 days ago during the final game of the season while making a cutting move, where his foot was planted and rotated outward and his knee buckled inward. He admits to feeling a ‘pop’ and having immediate pain. He denies any locking, clicking, or giving way since the event. Physical examination reveals an antalgic gait with avoidance of active knee extension. His left knee demonstrates moderate, diffuse swelling and is very tender to palpation along the joint line. Which of the following structures is most likely damaged in this patient?", "answer": "Anterior cruciate ligament", "options": {"A": "Anterior cruciate ligament", "B": "Lateral meniscus", "C": "Medial collateral ligament", "D": "Medial meniscus", "E": "Posterior cruciate ligament"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 9-year-old girl is brought to the pediatrician by her parents because of unremitting cough, fevers, night sweats, anorexia, and weight loss for 4 weeks. Her vaccinations are up to date. When asked about recent exposure to an ill person, the parents mention that she is frequently under the care of a middle-aged woman who recently immigrated from a small rural community in north India. Her temperature is 39.0°C (102.2°F), respiratory rate is 30/min, and heart rate is 120/min. Her weight is 2 standard deviations below normal for her age. Chest auscultation shows fine crackles in both lung fields.  The patient is referred to a nearby children’s hospital where her clinical condition rapidly worsens over several weeks. A chest radiograph is shown. Microbiological evaluation of a bronchial aspirate reveals an organism with a cell wall that is impervious to Gram stain. Which of the following best describes the cell wall of the causative agent?", "answer": "High mycolic acid content", "options": {"A": "Low muramic acid content", "B": "High mycolic acid content", "C": "High ergosterol content", "D": "Absence of cellular wall", "E": "Teichoic acid-rich cellular wall"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man is brought to the emergency room with complaints of severe substernal chest pain for the last hour. The pain started suddenly, and the patient describes the pain as “going into the shoulder”. The patient took aspirin at home and has been given multiple doses of sublingual nitroglycerin, but the pain has not subsided. He has a blood pressure of 112/84 mm Hg, the pulse is 63/min, the respiratory rate is 18/min, and the temperature is 36.9°C (98.0°F). Cardiac auscultation reveals normal S1 and S2 sounds, however, an additional S4 sound is heard. The patient is sweating profusely, and the lungs are clear to auscultation. No jugular venous distension or pedal edema is observed. His initial ECG shows ST elevation in leads II, III, and aVF. Which of the following will likely have the most benefit in this patient?", "answer": "Percutaneous coronary intervention", "options": {"A": "Antiarrhythmics", "B": "Beta blockers", "C": "Clopidogrel", "D": "Thrombolytics", "E": "Percutaneous coronary intervention"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old female comes to the physician for evaluation of a delayed menstrual period and intermittent lower abdominal pain for 2 days. Menarche occurred at the age of 12 years, and menses have occurred at regular 28-day intervals. Her last menstrual period was 7 weeks ago. Two years ago, she was treated for chlamydia infection. Pelvic examination shows a soft, mildly enlarged uterus. Endometrial biopsy shows decidualization of the endometrium without chorionic villi. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Fertilized ovum outside the uterus", "options": {"A": "Benign proliferation of myometrial smooth muscle", "B": "Ectopic endometrial tissue", "C": "Fertilized ovum outside the uterus", "D": "Endometrial infiltration by plasma cells", "E": "Empty ovum fertilized by two sperm"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-year-old girl with previously diagnosed sickle cell anemia presents to the emergency room with a low-grade fever, malaise, petechiae on her arms, and a rash on her face. She regularly takes hydroxyurea and receives blood transfusions to treat her condition. Her blood tests show a hemoglobin of 4.0 g/dL, MCV of 87 fl, and 2% reticulocyte count. An attempted bone marrow biopsy was  a dry, empty tap. What is the most likely diagnosis?", "answer": "Aplastic crisis", "options": {"A": "Aplastic crisis", "B": "Gastrointestinal bleeding", "C": "Anemia of chronic disease", "D": "Reaction to the blood transfusions", "E": "Sequestration crisis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old man comes to the physician because of progressive daytime sleepiness and exertional dyspnea for the past 6 months. Physical examination shows conjunctival pallor and several subcutaneous purple spots on his legs. His hemoglobin concentration is 8.5 g/dL, leukocyte count is 3,000/mm3, and platelet count is 16,000/mm3. Which of the following laboratory values is most likely to be increased in this patient?", "answer": "Erythropoietin concentration", "options": {"A": "Haptoglobin concentration", "B": "Transferrin concentration", "C": "Reticulocyte count", "D": "Erythropoietin concentration", "E": "Lactate dehydrogenase concentration"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old man is referred to a physical therapist due to limitation of movement in the wrist and fingers of his left hand. He cannot hold objects or perform daily activities with his left hand. He broke his left arm at the humerus one month ago. The break was simple and treatment involved a cast for one month. Then he lost his health insurance and could not return for follow up. Only after removing the cast did he notice the movement issues in his left hand and wrist. His past medical history is otherwise insignificant, and vital signs are within normal limits. On examination, the patient’s left hand is pale and flexed in a claw-like position. It is firm and tender to palpation. Right radial pulse is 2+ and left radial pulse is 1+. The patient is unable to actively extend his fingers and wrist, and passive extension is difficult and painful. Which of the following is a proper treatment for the presented patient?", "answer": "Surgical release", "options": {"A": "Surgical release", "B": "Needle fasciotomy", "C": "Corticosteroid injections", "D": "Collagenase injections", "E": "Botulinum toxin injections"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old man is brought to the emergency department because of progressive left-sided scrotal pain for 4 hours. He describes the pain as throbbing in nature and 6 out of 10 in intensity. He has vomited once on the way to the hospital. He has had pain during urination for the past 4 days. He has been sexually active with 2 female partners over the past year and uses condoms inconsistently. His father was diagnosed with testicular cancer at the age of 51 years. He appears anxious. His temperature is 36.9°C (98.42°F), pulse is 94/min, and blood pressure is 124/78 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. Examination shows a tender, swollen left testicle and an erythematous left hemiscrotum. Urine dipstick shows leukocyte esterase; urinalysis shows WBCs. Which of the following is the most appropriate next step in management?", "answer": "Scrotal ultrasonography", "options": {"A": "Measurement of serum α-fetoprotein level", "B": "CT scan of the abdomen and pelvis", "C": "Surgical exploration", "D": "Scrotal ultrasonography", "E": "Measurement of serum mumps IgG titer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-month-old boy is brought to the physician because of a lesion on his right thigh. Yesterday, he was administered all scheduled childhood immunizations. His vital signs are within normal limits. Physical examination shows a 2-cm sized ulcer with surrounding induration over the right anterolateral thigh. Which of the following is the most likely cause of his symptoms?", "answer": "Immune complex deposition", "options": {"A": "Dermal mast cell activation", "B": "Immune complex deposition", "C": "Intradermal acantholysis", "D": "Infective dermal inflammation", "E": "T lymphocyte mediated hypersensitivity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old boy presents to a pediatric orthopedic surgeon for evaluation of spinal curvature. His primary care physician noticed during an annual checkup that the boy's shoulders were uneven, and radiograph revealed early onset scoliosis. His past medical history is significant for multiple fractures as well as short stature. Based on the early presentation of scoliosis and the unusual history of fractures, the surgeon orders further workup and discovers a genetic mutation in an extracellular protein. This protein exists in two different forms. The first is an insoluble dimer that is linked by disulfide bonds and links integrins to the extracellular matrix. The second is a soluble protein that assists with clotting. Based on these descriptions, which of the following proteins is most likely mutated in this patient?", "answer": "Fibronectin", "options": {"A": "Dermatan sulfate", "B": "Fibrillin", "C": "Fibronectin", "D": "Type 1 collagen", "E": "Type 3 collagen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 80-year-old woman is brought to the physician by her 2 daughters for worsening memory loss. They report that their mother is increasingly forgetful about recent conversations and events. She is unable to remember her appointments and commitments she has made. 3 years ago, the patient was moved into an elder care facility because she was often getting lost on her way home and forgetting to take her medications. The patient reports that she is very socially active at her new home and has long conversations with the other residents about her adventures as an air hostess during her youth. Which of the following cerebral pathologies is most likely present in this patient?", "answer": "Neurofibrillary tangles", "options": {"A": "Demyelination", "B": "Intracytoplasmic vacuoles", "C": "Lacunar infarcts", "D": "Lewy bodies", "E": "Neurofibrillary tangles"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An experimental new drug (SD27C) is being studied. This novel drug delivers insulin via the intranasal route. Consent is obtained from participants who are diabetic and are taking insulin as their current treatment regimen to participate in a clinical trial. 500 patients consent and are divided into 2 groups, and a double-blind clinical trial was conducted. One group received the new formulation (SD27C), while the second group received regular insulin via subcutaneous injection. The results showed that the treatment outcomes in both groups are the same. SD27C is currently under investigation in which phase of the clinical trial?", "answer": "Phase III", "options": {"A": "Phase IV", "B": "Phase III", "C": "Post-market surveillance", "D": "Phase II", "E": "Phase I"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old woman presents with progressive gait difficulty, neck pain, and bladder incontinence. She also complains of urinary urgency. Past medical history is significant for uncontrolled diabetes mellitus with a previous hemoglobin A1c of 10.8%. Physical examination reveals slightly increased muscle tone in all limbs with brisk tendon reflexes. Sensory examination reveals a decrease of all sensations in a stocking and glove distribution. Her gait is significantly impaired. She walks slowly with small steps and has difficulty turning while walking. She scores 23 out of 30 on a mini-mental state examination (MMSE). A brain MRI reveals dilated ventricles with a callosal angle of 60 degrees and mild cortical atrophy. What is the most appropriate next step in the management of this patient?", "answer": "Large-volume lumbar tap", "options": {"A": "Acetazolamide", "B": "Donepezil", "C": "Large-volume lumbar tap", "D": "Levodopa", "E": "Ventriculoperitoneal shunt"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 48-year-old woman presents to the emergency department because of increasingly severe right upper abdominal pain, fever, and non-bloody vomiting for the last 5 hours. The pain is dull, intermittent, and radiates to her right shoulder. During the past 3 months, she has had recurring abdominal discomfort after meals. The patient underwent an appendectomy more than 30 years ago. She has hypertension, diabetes mellitus type 2, and chronic back pain. She takes bisoprolol, metformin, and ibuprofen daily. She is 171 cm (5 ft 6 in) tall and weighs 99 kg (218 lb). Her BMI is 35.2 kg/m2. She appears uncomfortable and is clutching her abdomen. Her temperature is 38.5°C (101.3°F), pulse is 108/min, and blood pressure is 150/82 mm Hg. Abdominal examination shows right upper quadrant abdominal tenderness and guarding. Upon deep palpation of the right upper quadrant, the patient pauses during inspiration. Laboratory studies show the following:\nBlood\nHemoglobin 13.1 g/dL\nLeukocyte count 10,900/mm3\nPlatelet count 236,000/mm3\nMean corpuscular volume 89/µm3\nSerum\nUrea nitrogen 28 mg/dL\nGlucose 89 mg/dL\nCreatinine 0.7 mg/dL\nBilirubin  \nTotal 1.6 mg/dL\nDirect 1.1 mg/dL\nAlkaline phosphatase 79 U/L\nAlanine aminotransferase (ALT, GPT) 28 U/L\nAspartate aminotransferase (AST, GOT) 32 U/L\nAn X-ray of the abdomen shows no abnormalities. Further evaluation of the patient is most likely to reveal which of the following?", "answer": "History of multiple past pregnancies", "options": {"A": "Elevated carbohydrate-deficient transferrin", "B": "Frequent, high-pitched bowel sounds on auscultation", "C": "History of multiple past pregnancies", "D": "History of recent travel to Indonesia", "E": "History of recurrent sexually transmitted infections"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old man is running a marathon (42.2 km) on a hot summer day and collapses about halfway through the run. Emergency personnel are called and find him having a seizure. As the seizure subsides, the runner exhibits confusion, dry lips and decreased skin turgor. On the way to the emergency department, he denies taking medication or having a history of seizures. He reports that he drank water, but he admits that it was probably not enough. Which of the following would be the next best step in the management of this patient?", "answer": "3% NaCl", "options": {"A": "Indapamide", "B": "Relcovaptan", "C": "3% NaCl", "D": "0.9% NaCl", "E": "Furosemide"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-year-old woman comes to the physician for a 2-month history of chest pain and heartburn after meals. The patient reports that the pain is worse at night and especially when lying down. She has a history of Raynaud's disease treated with nifedipine. There is no family history of serious illness. She emigrated to the US from Nigeria 5 years ago. She does not smoke or drink alcohol. Vital signs are within normal limits. Cardiopulmonary examination shows no abnormalities. Thickening and hardening of the skin is seen on the hands and face. There are several firm, white nodules on the elbows and fingertips. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Anticentromere antibodies", "options": {"A": "Anti-RNA polymerase III antibodies", "B": "Anti-U1 RNP antibodies", "C": "Anticentromere antibodies", "D": "Anti-Scl-70 antibodies", "E": "Anti-dsDNA antibodies"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man is evaluated in the clinic for several episodes of diarrhea during the past 2 months. He denies having fever or abdominal pain and states that his diarrhea has been getting worse despite the use of over-the-counter loperamide and bismuth compounds. Upon further questioning, he recalls having multiple episodes of a burning sensation in his neck and upper chest, associated with redness and flushing of his face, which lasted for a few seconds. Because of his hypertension and dyslipidemia, the man is taking amlodipine and following a low-calorie diet. Physical examination shows that the blood pressure is 129/89 mm Hg, the pulse rate is 78/min, the respiratory rate is 14/min, and the temperature is 36.6°C (98.0°F). His abdomen is lax with no tenderness or rigidity, and rectal examination shows no blood in the rectal vault. Cardiac auscultation reveals a 3/6 holosystolic murmur in the tricuspid area, which increases in intensity with inspiration. Altered metabolism of which of the following amino acids is most likely the explanation for this patient’s presentation?", "answer": "Tryptophan", "options": {"A": "Phenylalanine", "B": "Tryptophan", "C": "Homocysteine", "D": "Arginine", "E": "Glycine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-month-old girl is brought to the emergency department shortly after a 2-minute episode of rhythmic eye blinking and uncontrolled shaking of all limbs. She was unresponsive during the episode. For the past few days, the girl has had a fever and mild nasal congestion. Her immunizations are up-to-date. Her temperature is 39.2°C (102.6°F), pulse is 110/min, respirations are 28/min, and blood pressure is 88/45 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 100%. She is sleepy but opens her eyes when her name is called. Examination shows moist mucous membranes. Neurologic examination shows no abnormalities. The neck is supple with normal range of motion. An oral dose of acetaminophen is administered. On re-evaluation, the girl is alert and playing with toys in the examination room. Which of the following is the most appropriate next step in management?", "answer": "Discharge the patient", "options": {"A": "Perform an EEG", "B": "Perform a CT scan of the head", "C": "Observe the patient for 24 hours", "D": "Discharge the patient", "E": "Administer lorazepam"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy presents with involuntary jerks seen in his upper extremities. The patient’s mother says that “his eyes move in different directions every now and then”. Last winter, the patient had chickenpox but otherwise has always been healthy. His vital signs are a blood pressure of 100/90 mm Hg, temperature of 36.8°C (98.2°F), and respiratory rate of 17/min. On physical examination, the patient’s eyes move chaotically in all directions. Laboratory tests are unremarkable, except for a random urinary vanillylmandelic acid (VMA) level of 18 mg/g creatinine (reference range for children aged 2–4 years: < 13 mg/g creatinine). An abdominal ultrasound shows a 2 cm x 3 cm x 5 cm mass in the left adrenal gland. A biopsy of the mass reveals neuroblasts arranged in a rosette pattern. Which of the following oncogenes is most commonly associated with this condition?", "answer": "MYCN", "options": {"A": "MYCN", "B": "KRAS", "C": "ALK", "D": "JAK2", "E": "RET"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old man undergoes surgical intervention due to a right upper quadrant stab wound. His gallbladder was found to be lacerated and is removed. It is sent for histological evaluation. The pathologist examines the slide shown in the exhibit and identifies several structures numbered the image. Which of the following statements is correct?", "answer": "This section is taken from the site which does not adjoin liver", "options": {"A": "The function of the cells in area 1 is to secrete bile", "B": "The cells in area 3 are inactivated by cholecystokinin", "C": "The cells in area 2 belong to muscularis propria", "D": "This section is taken from the site which does not adjoin liver", "E": "Normally, there should be goblet cells among the cells in area 1"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old man presents to the emergency department for a fever and abdominal pain. The patient states that his pain has been worsening over the past week in the setting of a fever. He has a past medical history of IV drug abuse and multiple admissions for septic shock. His temperature is 102°F (38.9°C), blood pressure is 94/54 mmHg, pulse is 133/min, respirations are 22/min, and oxygen saturation is 100% on room air. Physical exam is notable for a murmur over the left upper sternal border. Abdominal exam reveals left upper quadrant tenderness. Laboratory values are ordered as seen below.\n\nHemoglobin: 15 g/dL\nHematocrit: 44%\nLeukocyte count: 16,700/mm^3\nPlatelet count: 299,000/mm^3\n\nWhich of the following is the most likely diagnosis?", "answer": "Splenic abscess", "options": {"A": "Appendicitis", "B": "Diverticulitis", "C": "Hepatic abscess", "D": "Mesenteric ischemia", "E": "Splenic abscess"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old man is brought to the emergency department from a senior-care facility after he was found with a decreased level of consciousness and fever. His personal history is relevant for colorectal cancer that was managed with surgical excision of the tumor. Upon admission, he is found to have a blood pressure of 130/80 mm Hg, a pulse of 102/min, a respiratory rate of 20/min, and a body temperature 38.8°C (101.8°F). There is no rash on physical examination; he is found to have neck rigidity, confusion, and photophobia. There are no focal neurological deficits. A head CT is normal without mass or hydrocephalus. A lumbar puncture was performed and cerebrospinal fluid (CSF) is sent to analysis while ceftriaxone and vancomycin are started. Which of the following additional antimicrobials should be added in the management of this patient?", "answer": "Ampicillin", "options": {"A": "Ampicillin", "B": "Amphotericin", "C": "Clindamycin", "D": "Trimethoprim-sulfamethoxazole (TMP-SMX)", "E": "Meropenem"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 13-year-old boy re-presents to his pediatrician with a new onset rash that began a few days after his initial visit. He initially presented with complaints of sore throat but was found to have a negative strep test. His mother demanded that he be placed on antibiotics, but this was refused by his pediatrician. The boy's father, a neurologist, therefore, started him on penicillin. Shortly after starting the drug, the boy developed a fever and a rash. The patient is admitted and his symptoms worsen. His skin begins to slough off, and the rash covers over 30% of his body. His oropharynx and corneal membranes are also affected. You examine him at the bedside and note a positive Nikolsky's sign. What is the most likely diagnosis?", "answer": "Toxic Epidermal Necrolysis", "options": {"A": "Erythema Multiforme", "B": "Stevens-Johnson Syndrome", "C": "Toxic Epidermal Necrolysis", "D": "Rocky Mounted Spotted Fever", "E": "Pemphigus Vulgaris"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 16-year-old girl who recently immigrated to the United States from Bolivia presents to her primary care physician with a chief complaint of inattentiveness in school. The patient's teacher describes her as occasionally \"day-dreaming\" for periods of time during which the patient does not respond or participate in school activities. Nothing has helped the patient change her behavior, including parent-teacher conferences or punishment. The patient has no other complaints herself. The only other concern that the patient's mother has is that upon awakening she notices that sometimes the patient's arm will jerk back and forth. The patient states she is not doing this intentionally. The patient has an unknown past medical history and is currently not on any medications. On physical exam you note a young, healthy girl whose neurological exam is within normal limits. Which of the following is the best initial treatment?", "answer": "Valproic acid", "options": {"A": "Carbamazepine", "B": "Ethosuximide", "C": "Valproic acid", "D": "Lamotrigine", "E": "Cognitive behavioral therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 29-year-old man is brought to the emergency room 6 hours after the onset of severe epigastric pain and vomiting. His heart rate is 110/min and blood pressure is 98/72 mm Hg. He is diagnosed with acute pancreatitis, and fluid resuscitation with normal saline is initiated. Which of the following is the most likely immediate effect of fluid resuscitation in this patient?", "answer": "Increase in myocardial oxygen demand", "options": {"A": "Increase in cardiac afterload", "B": "Increase in volume of distribution", "C": "Increase in myocardial oxygen demand", "D": "Increase in plasma oncotic pressure", "E": "Increase in glomerular filtration fraction\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman presents with abdominal pain and discomfort for the past 3 days. She was diagnosed with irritable bowel syndrome (IBS) a couple of years ago, managed until recently with imipramine, psyllium, and loperamide. 5 days ago, because she had developed alternating diarrhea and constipation, bloating, and abdominal pain on her medication, she was started on alosetron. Her current temperature is 39.0°C (102.2°F), the heart rate is 115/min, the blood pressure is 90/60 mm Hg and the respiratory rate is 22/min. Abdominal examination shows diffuse tenderness to palpation with guarding but no rebound. Bowel sounds are hypoactive on auscultation. A fecal occult blood test is positive and laboratory tests show her white cell count to be 15,800/µL. Arterial blood gas (ABG) analysis reveals a metabolic acidosis Which of the following is the most likely diagnosis in this patient?", "answer": "Ischemic colitis", "options": {"A": "Pseudomembranous colitis", "B": "Crohn’s disease", "C": "Perforated duodenal ulcer", "D": "Appendicitis", "E": "Ischemic colitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old patient with a history of anxiety, chronic constipation, chronic headaches, and chronic hypertension presents to the emergency room with severe right flank pain radiating to his scrotum. A urinalysis with stone analysis is performed and the results are shown in figure A. Prior to discharge, it is noted that the patients BP is still 170/110 mmHg. Furthermore, his calcium and PTH levels were both found to be increased. Which of the following representative histology slides of thyroid tissue represents a potential complication of the patients condition?", "answer": "Medullary thyroid cancer", "options": {"A": "Anaplastic thyroid cancer", "B": "Medullary thyroid cancer", "C": "Papillary thyroid cancer", "D": "Lymphoma", "E": "Follicular thyroid cancer"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-year-old boy presents with a painful rash for 1 day. He says that the reddish, purple rash started on his forearm but has now spread to his abdomen. He says there is a burning pain in the area where the rash is located. He also says he has had a stuffy nose for several days. Past medical history is significant for asthma and epilepsy, medically managed. Current medications are a daily chewable multivitamin, albuterol, budesonide, and lamotrigine. On physical examination, there is a red-purple maculopapular rash present on upper extremities and torso. There are some blisters present over the rash, as shown in the image, which is also present in the oral mucosa. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Lamotrigine", "options": {"A": "Budesonide", "B": "Infection", "C": "Lamotrigine", "D": "Multivitamin", "E": "Albuterol"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old man presents to the endocrinologist with complaints of increased shoe size and headaches in the morning. These symptoms have developed gradually over the past year but have become especially concerning because he can no longer wear his normal-sized boots. He denies any other symptoms, including visual changes. He was recently started on lisinopril by his primary care physician for high blood pressure. His vital signs are within normal limits and stable. On exam, the endocrinologist notes the findings shown in Figures A and B. These facial features are especially striking when contrasted with his drivers license from 10 years prior, when his jaw was much less prominent. The endocrinologist sends a screening blood test to work-up the likely diagnosis. Which of the following organs or glands produces the molecule being tested in this screening?", "answer": "Liver", "options": {"A": "Anterior pituitary gland", "B": "Liver", "C": "Posterior pituitary gland", "D": "Pancreas", "E": "Kidney"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 64-year-old man is brought to the emergency department because of dull lower abdominal pain for 3 hours. He has not urinated for 24 hours and has not passed stool for over 3 days. He was diagnosed with herpes zoster 4 weeks ago and continues to have pain even after his rash resolved. He has hypertension, benign prostatic hyperplasia, and coronary artery disease. Physical examination shows a tender, palpable suprapubic mass. Bowel sounds are hypoactive. Abdominal ultrasound shows a large anechoic mass in the pelvis. Which of the following drugs most likely accounts for this patient's current symptoms?", "answer": "Desipramine", "options": {"A": "Simvastatin", "B": "Pregabalin", "C": "Amlodipine", "D": "Valproate", "E": "Desipramine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-year-old girl presents to the pediatric dermatologist with an expanding, but otherwise asymptomatic erythematous patch on her right shoulder, which she first noticed 3 days ago. The girl states the rash started as a small red bump but has gradually progressed to its current size. No similar lesions were observed elsewhere by her or her mother. She has felt ill and her mother has detected intermittent low-grade fevers. During the skin examination, a target-like erythematous patch, approximately 7 cm in diameter, was noted on the left shoulder (as shown in the image). Another notable finding was axillary lymphadenopathy. On further questioning it was revealed that the patient went camping with her grandfather approximately 11 days ago; however, she does not recall any insect bites or exposure to animals. The family has a pet cat living in their household. Based on the history and physical examination results, what is the most likely diagnosis?", "answer": "Lyme disease", "options": {"A": "Tinea corporis", "B": "Lyme disease", "C": "Granuloma anulare", "D": "Pityriasis rosea", "E": "Hansen’s disease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 75-year-old man with a 35-pack-year history of smoking is found to be lethargic three days being admitted with a femur fracture following a motor vehicle accident. His recovery has been progressing well thus far, though pain continued to be present. On exam, the patient minimally responsive with pinpoint pupils. Vital signs are blood pressure of 115/65 mmHg, HR 80/min, respiratory rate 6/min, and oxygen saturation of 87% on room air. Arterial blood gas (ABG) shows a pH of 7.24 (Normal: 7.35-7.45), PaCO2 of 60mm Hg (normal 35-45mm Hg), a HCO3 of 23 mEq/L (normal 21-28 mEq/L) and a Pa02 of 60 mmHg (normal 80-100 mmHg). Which of the following is the most appropriate therapy at this time?", "answer": "Naloxone", "options": {"A": "Repeat catheterization", "B": "Glucocorticoids", "C": "Heparin", "D": "Naloxone", "E": "Emergent cardiac surgery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman comes to the physician for the evaluation of infertility. She has been unable to conceive for the past 2 years. Menses occur at 45 to 80-day intervals. She is 168 cm (5 ft 6 in) tall and weighs 77 kg (170 lb); BMI is 27.4 kg/m2. Physical examination shows facial acne and pigmented hair on the upper lip. Serum studies show elevated levels of testosterone and an LH:FSH ratio of 4:1. Treatment with the appropriate drug for this patient's infertility is begun. Which of the following is the primary mechanism of action of this drug?", "answer": "Inhibition of hypothalamic estrogen receptors", "options": {"A": "Activation of pituitary dopamine receptors", "B": "Inhibition of endometrial progesterone receptors", "C": "Activation of ovarian luteinizing hormone receptors", "D": "Activation of granulosa cell aromatase", "E": "Inhibition of hypothalamic estrogen receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A six-year-old male presents to the pediatrician for a well child visit. The patient’s parents report that they are struggling to manage his temper tantrums, which happen as frequently as several times per day. They usually occur in the morning before school and during mealtimes, when his parents try to limit how much he eats. The patient often returns for second or third helpings at meals and snacks throughout the day. The patient’s parents have begun limiting the patient’s food intake because he has been gaining weight. They also report that the patient recently began first grade but still struggles with counting objects and naming letters consistently. The patient sat without support at 11 months of age and walked at 17 months of age. He is in the 99th percentile for weight and 5th percentile for height. On physical exam, he has almond-shaped eyes and a downturned mouth. He has poor muscle tone.\n\nWhich of the following additional findings would most likely be seen in this patient?", "answer": "Hypogonadism", "options": {"A": "Ataxia", "B": "Hemihyperplasia", "C": "Hypogonadism", "D": "Macroorchidism", "E": "Webbed neck"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old and his caregiver present for a follow-up after a transthoracic needle biopsy of one of the large lesions in his chest was reported as non-small cell carcinoma of the lung. Previously, a chest CT revealed numerous nodules in the lungs bilaterally. The chest CT was ordered after the patient experienced a persistent cough with hemoptysis and a history of multiple episodes of pneumonia over the past year. The patient has a history of dementia and is a poor historian. The caregiver states that the patient has no history of smoking and that he was a lawyer before he retired, 10 years ago. The caregiver can only provide a limited medical history, but states that the patient sees another doctor “to monitor his prostate”. Which of the following is true regarding the pathogenesis of the nodules seen in this patient?", "answer": "Tumors seeded via the pulmonary arteries", "options": {"A": "Aspergillus infection leading to a formation of a 'fungus ball'", "B": "Malignant transformation of neuroendocrine cells", "C": "Infection of the lung parenchyma with a gram-negative bacteria grown on charcoal yeast agar", "D": "Proliferation of cells that contain glands that produce mucin", "E": "Tumors seeded via the pulmonary arteries"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 21-year-old African American female presents to her primary care physician reporting a history of excess hair growth. She has to shave her face and chest on a regular basis. She is sexually active and uses condoms for protection. Her last period was two months ago and she reports having 5-6 menstrual periods per year at irregular intervals. She has no past medical history and takes no medications. She drinks socially and does not smoke. Her family history is notable for heart disease in her father and endometrial cancer in her mother. Her temperature is 98.6°F (37°C), blood pressure is 125/85 mmHg, pulse is 95/min, and respirations are 16/min. The physician considers starting the patient on a medication that is also indicated in the treatment of histoplasmosis. This medication primary acts by inhibiting which of the following proteins?", "answer": "Desmolase", "options": {"A": "Squalene epoxidase", "B": "Desmolase", "C": "Aromatase", "D": "5-alpha-reductase", "E": "1,3-beta-glucan synthase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 18-year-old woman comes to the emergency department for evaluation of intractable vomiting and uterine cramping. Her last menstrual period was 7 weeks ago. Serum β-human chorionic gonadotropin concentration is 170,000 mIU/mL. A transvaginal ultrasound shows a complex intrauterine mass with numerous anechoic spaces and multiple ovarian cysts. The patient undergoes dilation and curettage, which shows hydropic villi with diffuse, circumferential trophoblastic proliferation. Karyotype analysis of the specimen is most likely to show which of the following?", "answer": "46,XX of paternal origin only", "options": {"A": "46,XX of maternal origin only", "B": "69,XXY of paternal origin only", "C": "46,XX of paternal origin only", "D": "46,XY of both maternal and paternal origin", "E": "69,XYY of both maternal and paternal origin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old man presents to the emergency department for sudden pain in his foot. The patient states that when he woke up, he experienced severe pain in his right great toe. The patient’s wife immediately brought him to the emergency department. The patient has a past medical history of diabetes mellitus, obesity, and hypertension and is currently taking insulin, metformin, lisinopril, and ibuprofen. The patient is a current smoker and smokes 2 packs per day. He also drinks 3 glasses of whiskey every night. The patient is started on IV fluids and corticosteroids. His blood pressure, taken at the end of this visit, is 175/95 mmHg. As the patient’s symptoms improve, he asks how he can avoid having these symptoms again in the future. Which of the following is the best initial intervention in preventing a future episode of this patient’s condition?", "answer": "Lifestyle measures", "options": {"A": "Allopurinol", "B": "Hydrochlorothiazide", "C": "Lifestyle measures", "D": "Niacin", "E": "Probenecid"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 14-year-old girl is brought to the physician for a follow-up examination. She has had frequent falls over the past two years. During the past six months, the patient has been unable to walk or stand without assistance and she now uses a wheelchair. Her mother was diagnosed with a vestibular schwannoma at age 52. Her vital signs are within normal limits. Her speech is slow and unclear. Neurological examination shows nystagmus in both eyes. Her gait is wide-based with irregular and uneven steps. Her proprioception and vibration sense are absent. Muscle strength is decreased especially in the lower extremities. Deep tendon reflexes are 1+ bilaterally. The remainder of the examination shows kyphoscoliosis and foot inversion with hammer toes. This patient is most likely to die from which of the following complications?", "answer": "Heart failure", "options": {"A": "Posterior fossa tumors", "B": "Renal cell carcinoma", "C": "Heart failure", "D": "Leukemia", "E": "Aspiration pneumonia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A drug discovery team is conducting research to observe the characteristics of a novel drug under different experimental conditions. The drug is converted into the inactive metabolites by an action of an enzyme E. After multiple experiments, the team concludes that as compared to physiologic pH, the affinity of the enzyme E for the drug decreases markedly in acidic pH. Co-administration of an antioxidant A increases the value of Michaelis-Menten constant (Km) for the enzyme reaction, while co-administration of a drug B decreases the value of Km. Assume the metabolism of the novel drug follows Michaelis-Menten kinetics at the therapeutic dose, and that the effects of different factors on the metabolism of the drug are first-order linear. For which of the following conditions will the metabolism of the drug be the slowest?", "answer": "Acidic pH, co-administration of antioxidant A, no administration of drug B", "options": {"A": "Physiologic pH, co-administration of antioxidant A, no administration of drug B", "B": "Acidic pH, co-administration of antioxidant A, no administration of drug B", "C": "Acidic pH, co-administration of antioxidant A and of drug B", "D": "Acidic pH, co-administration of drug B, no administration of antioxidant A", "E": "Acidic pH, without administration of antioxidant A or drug B"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman is brought to the emergency department 30 minutes after the onset of severe dyspnea. On arrival, she is unresponsive. Her pulse is 160/min, respirations are 32/min, and blood pressure is 60/30 mm Hg. CT angiography of the chest shows extensive pulmonary embolism in both lungs. She is given a drug that inhibits both thrombin and factor Xa. Which of the following medications was most likely administered?", "answer": "Unfractioned heparin", "options": {"A": "Ticagrelor", "B": "Apixaban", "C": "Unfractioned heparin", "D": "Fondaparinux", "E": "Tenecteplase\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old man is brought to the emergency department because of confusion, weight loss, and anuria. He has chronic kidney disease, hypertension, and type 2 diabetes mellitus. He was diagnosed with acute lymphoblastic leukemia at the age of 8 years and was treated with an allogeneic stem cell transplantation. He is HIV-positive and has active hepatitis C virus infection. He drinks around 8 cans of beer every week. His current medications include tenofovir, emtricitabine, atazanavir, daclatasvir, sofosbuvir, insulin, amlodipine, and enalapril. He appears lethargic. His temperature is 36°C (96.8°F), pulse is 130/min, respirations are 26/min, and blood pressure is 145/90 mm Hg. Examination shows severe edema in his legs and generalized muscular weakness. Auscultation of the lung shows crepitant rales. Laboratory studies show positive HCV antibody and positive HCV RNA. His HIV viral load is undetectable and his CD4+ T-lymphocyte count is 589/μL. Six months ago, his CD4+ T-lymphocyte count was 618/μL. An ECG of the heart shows arrhythmia with frequent premature ventricular contractions. Arterial blood gas analysis on room air shows:\npH 7.23\nPCO2 31 mm Hg\nHCO3- 13 mEq/L\nBase excess -12 mEq/L\nThe patient states he would like to donate organs or tissues in the case of his death. Which of the following is an absolute contraindication for organ donation in this patient?\"", "answer": "No absolute contraindications", "options": {"A": "HIV infection", "B": "Childhood leukemia", "C": "Acute kidney injury", "D": "Alcoholism", "E": "No absolute contraindications"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old G1P0 presents to her obstetrician for her normal 30-week obstetric appointment. She reports that she feels well and has no complaints. Her past medical history is notable for intermittent asthma. Her only medications are prenatal vitamins. She has gained 10 pounds, more than expected given her current stage of pregnancy. Abdominal ultrasound reveals the presence of twins with separate amniotic sacs that share a common chorion and placenta. During which time interval following fertilization did the morula divide into two in this mother?", "answer": "Days 4-8", "options": {"A": "Days 1-3", "B": "Days 4-8", "C": "Days 9-12", "D": "Days 13-15", "E": "Day 16+"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-month-old girl is brought to the physician by her father for a routine well-child examination. She is given a vaccine that contains polyribosylribitol phosphate conjugated to a toxoid carrier. The vaccine is most likely to provide immunity against which of the following pathogens?", "answer": "Haemophilus influenzae", "options": {"A": "Streptococcus pneumoniae", "B": "Corynebacterium diphtheriae", "C": "Neisseria meningitidis", "D": "Haemophilus influenzae", "E": "Bordetella pertussis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A research group designed a study to investigate the epidemiology of syphilis in the United States. The investigators examined per capita income and rates of syphilis in New York City, Los Angeles, Chicago, and Houston. Data on city-wide syphilis rates was provided by each city's health agency. The investigators ultimately found that the number of new cases of syphilis was higher in low-income neighborhoods. This study is best described as which of the following?", "answer": "Ecological study", "options": {"A": "Prospective cohort study", "B": "Case-control study", "C": "Ecological study", "D": "Case series", "E": "Double-blind clinical trial"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-year-old girl is brought to her pediatrician complaining of painful urination over the last 5 days. She describes it as a burning and itching when she uses the bathroom and has never had a feeling like this before. She was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and is meeting all developmental milestones. Detailed history reveals that the parents have observed significant behavior changes in their daughter over the last 6 months such as social withdrawal and increased fearfulness. They have not identified a cause for these sudden behavioral changes. The pediatrician performs a complete physical examination. Upon genital examination, the girl becomes very nervous and begins to cry. After an examination of the vagina, the physician is concerned about a sexually transmitted disease. She orders testing and connects the family to child protective services for further investigation and counseling. Which of the following findings on physical examination of the vaginal region justifies the pediatrician’s suspicion?", "answer": "Yellow mucopurulent discharge", "options": {"A": "Erythematous and greasy yellowish scaling", "B": "Crusty weepy lesions accompanied by erythema and severe itching", "C": "Well-demarcated erythematous plaques with silvery-white scaling and mild pruritus", "D": "Linear pruritic rash with papules and vesicles", "E": "Yellow mucopurulent discharge"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 9-month-old girl is brought in by her father for a scheduled check-up with her pediatrician. He states that over the past 4-5 months she has had multiple ear infections. She was also hospitalized for an upper respiratory infection 2 months ago. Since then she has been well. She has started to pull herself up to walk. Additionally, the patient’s medical history is significant for eczema and allergic rhinitis. The father denies any family history of immunodeficiencies. There are no notable findings on physical exam. Labs are remarkable for low IgG levels with normal IgA, IgE, and IgM levels. Which of the following is the most likely etiology for the patient’s presentation?", "answer": "Delayed onset of normal immunoglobulins", "options": {"A": "Adenosine deaminase deficiency", "B": "Defect in Bruton tyrosine kinase", "C": "Delayed onset of normal immunoglobulins", "D": "Failure of B-cell differentiation", "E": "Impaired T cell signaling"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman is admitted to the inpatient psychiatry unit after her boyfriend reported she was “acting funny and refusing to talk.” The patient’s boyfriend states that he came home from work and found the patient sitting up in bed staring at the wall. When he said her name or waved his hand in front of her, she did not respond. When he tried to move her, she would remain in whatever position she was placed. The patient’s temperature is 99°F (37.2°C), blood pressure is 122/79 mmHg, pulse is 68/min, and respirations are 12/min with an oxygen saturation of 98% O2 on room air. During the physical exam, the patient is lying on the bed with her left arm raised and pointing at the ceiling. She resists any attempt to change her position. The patient remains mute and ignores any external stimuli. The patient’s medical history is significant for depression. She was recently switched from phenelzine to fluoxetine. Which of the following is the best initial therapy?", "answer": "Lorazepam", "options": {"A": "Benztropine", "B": "Cyproheptadine", "C": "Electroconvulsive therapy", "D": "Haloperidol", "E": "Lorazepam"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 8-year-old girl is brought to the emergency room for a 6-hour history of fever, sore throat, and difficulty swallowing. Physical examination shows pooling of oral secretions and inspiratory stridor. Lateral x-ray of the neck shows thickening of the epiglottis and aryepiglottic folds. Throat culture with chocolate agar shows small, gram-negative coccobacilli. The patient's brother is started on the recommended antibiotic for chemoprophylaxis. Which of the following is the primary mechanism of action of this drug?", "answer": "Inhibition of DNA-dependent RNA-polymerase", "options": {"A": "Inhibition of DNA-dependent RNA-polymerase", "B": "Inhibition of the 50S ribosomal subunit", "C": "Inhibition of prokaryotic topoisomerase II", "D": "Inhibition of the 30S ribosomal subunit", "E": "Inhibition of peptidoglycan crosslinking"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A group of medical students is studying bacteria and their pathogenesis. They have identified that a substantial number of bacteria cause human disease by producing exotoxins. Exotoxins are typically proteins, but they have different mechanisms of action and act at different sites. The following is a list of exotoxins together with mechanisms of action. Which of the following pairs is correctly matched?", "answer": "Cholera toxin - ADP-ribosylates Gs, keeping adenylate cyclase active and ↑ [cAMP]", "options": {"A": "Diphtheria toxin - cleaves synaptobrevin, blocking vesicle formation and the release of acetylcholine", "B": "Tetanospasmin - binds 60S ribosome subunit and inhibits protein synthesis", "C": "Cholera toxin - ADP-ribosylates Gs, keeping adenylate cyclase active and ↑ [cAMP]", "D": "Botulinum toxin - cleaves synaptobrevin, blocking vesicle formation and the release of the inhibitory neurotransmitters GABA and glycine", "E": "Anthrax toxin - ADP-ribosylates elongation factor - 2 (EF-2) and inhibits protein synthesis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 52-year-old woman comes to the physician because of a 3-month history of chest pain on exertion. She takes no medications. Cardiopulmonary examination shows no abnormalities. Cardiac stress ECG shows inducible ST-segment depressions in the precordial leads that coincide with the patient's report of chest pain and resolve upon cessation of exercise. Pharmacotherapy with verapamil is initiated. This drug is most likely to have which of the following sets of effects?\n $$$ End-diastolic volume (EDV) %%% Blood pressure (BP) %%% Contractility %%% Heart rate (HR) $$$", "answer": "↑ ↓ ↓ ↓", "options": {"A": "↓ ↓ ↓ ↑", "B": "No change no change no change no change", "C": "↓ ↓ ↓ no change", "D": "↓ ↓ no change ↑", "E": "↑ ↓ ↓ ↓"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old boy is brought to the physician by his parents who are concerned about his bizarre behavior. Over the past three months, he has become withdrawn from his friends and less interested in his classes and extracurricular activities. On several occasions, he has torn apart rooms in their home looking for “bugs” and states that the President is spying on him because aliens have told the government that he is a threat. Although he has always been quite clean in the past, his father notes that the patient’s room is now malodorous with clothes and dishes strewn about haphazardly. He also says that sometimes he can hear the devil speaking to him from inside his head. He has no medical problems, does not drink alcohol or use any drugs. Physical examination of the boy reveals no abnormalities. On mental status examination, the boy is oriented to person, place and time. He avoids eye contact and replies mostly with monosyllabic responses. He appears distracted, and confirms that he is hearing whispering voices in his head. What is the most appropriate diagnosis for this patient?", "answer": "Schizophreniform disorder", "options": {"A": "Brief psychotic disorder", "B": "Schizoid personality type", "C": "Schizoaffective disorder", "D": "Schizophreniform disorder", "E": "Schizophrenia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old female presents to the emergency department after a fall. She reports severe pain in her right hip and an inability to move her right leg. Her past medical history is notable for osteoporosis, rheumatoid arthritis, and has never undergone surgery before. The patient was adopted, and her family history is unknown. She has never smoked and drinks alcohol socially. Her temperature is 98.8°F (37.1°C), blood pressure is 150/90 mmHg, pulse is 110/min, and respirations are 22/min. Her right leg is shortened, abducted, and externally rotated. A radiograph demonstrates a displaced femoral neck fracture. She is admitted and eventually brought to the operating room to undergo right hip arthroplasty. While undergoing induction anesthesia with inhaled sevoflurane, she develops severe muscle contractions. Her temperature is 103.4°F (39.7°C). A medication with which of the following mechanisms of action is indicated in the acute management of this patient’s condition?", "answer": "Ryanodine receptor antagonist", "options": {"A": "Ryanodine receptor antagonist", "B": "GABA agonist", "C": "Serotonin 1B/1D agonist", "D": "NMDA receptor antagonist", "E": "Acetylcholine receptor agonist"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Recently, clarithromycin was found to have an increased risk of cardiac death in a Danish study. This study analyzed patients who were previously treated with clarithromycin or another antibiotic, and then they were followed over time to ascertain if cardiac death resulted. What type of study design does this represent?", "answer": "Cohort study", "options": {"A": "Randomized controlled trial", "B": "Cohort study", "C": "Cross-sectional study", "D": "Case control study", "E": "Non-inferiority trial"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 21-year-old male college student is brought to the emergency department by the campus police after he was found yelling at a bookshelf in the library. His roommate does not know of any prior episodes similar to this. His vital signs are within normal limits. The patient appears unkempt. On mental status examination, he talks very fast with occasional abrupt interruptions. He is agitated. He is disoriented to time and repeatedly tells the physician, “I hear the sun telling me that I was chosen to save the universe.” Urine toxicology screen is negative. Which of the following is the most appropriate pharmacotherapy?", "answer": "Ziprasidone", "options": {"A": "Haloperidol", "B": "Alprazolam", "C": "Dexmedetomidine", "D": "Valproic acid", "E": "Ziprasidone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old female presents to her primary care physician complaining of bloody stool. She reports several episodes of bloody stools over the past two months as well as a feeling of a mass near her anus. She has one to two non-painful bowel movements per day. She has a history of alcohol abuse and hypertension. Anoscopy reveals engorged vessels. Which of the following vessels most likely drains blood from the affected region?", "answer": "Superior rectal vein", "options": {"A": "Superior rectal vein", "B": "Inferior rectal vein", "C": "Internal pudendal vein", "D": "Middle rectal vein", "E": "Left colic vein"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Three weeks after delivering a healthy boy, a 28-year-old woman, gravida 1, para 1, comes to the physician for a postpartum check-up. Labor and delivery were uncomplicated. Two days after delivery she was diagnosed with postpartum endometritis and received intravenous clindamycin plus gentamicin for 2 days. She had painful swelling of the breasts at the beginning of lactation, but frequent breastfeeding and warm compresses prior to breastfeeding improved her symptoms. Physical examination shows no abnormalities. The patient asks about a reliable contraceptive method. Which of the following is the most appropriate recommendation?", "answer": "Progestin-only contraceptive pills", "options": {"A": "Spermicide", "B": "Basal body temperature method", "C": "Progestin-only contraceptive pills", "D": "Combined oral contraceptives", "E": "No contraception needed while lactating"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 83-year-old man is being seen in the hospital for confusion. The patient was admitted 4 days ago for pneumonia. He has been improving on ceftriaxone and azithromycin. Then 2 nights ago he had an episode of confusion. He was unsure where he was and attempted to leave. He was calmed down by nurses with redirection. He had a chest radiograph that was stable from admission, a normal EKG, and a normal urinalysis. This morning he was alert and oriented. Then this evening he became confused and agitated again. The patient has a history of benign prostatic hyperplasia, severe dementia, and osteoarthritis. He takes tamsulosin in addition to the newly started antibiotics. Upon physical examination, the patient is alert but orientated only to name. He tries to get up, falls back onto the bed, and grabs his right knee. He states, “I need to get to work. My boss is waiting, but my knee hurts.” He tries to walk again, threatens the nurse who stops him, and throws a plate at the wall. In addition to reorientation, which of the following is the next best step in management?", "answer": "Haloperidol", "options": {"A": "Haloperidol", "B": "Lorazepam", "C": "Morphine", "D": "Physical restraints", "E": "Rivastigmine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 61-year-old woman presents to her physician with foot tingling, numbness, and pain. She describes her pain as constant and burning and gives it 5 out of 10 on the visual analog pain scale. She also recalls several falls due to the numbness in her feet. She was diagnosed with diabetes mellitus and diabetic retinopathy 5 years ago. Since then, she takes metformin 1000 mg twice daily and had no follow-up visits to adjust her therapy. Her weight is 110 kg (242.5 lb), and her height is 176 cm (5 ft. 7 in). The vital signs are as follows: blood pressure is 150/90 mm Hg, heart rate is 72/min, respiratory rate is 12/min, and the temperature is 36.6°C (97.9°F). The patient has increased adiposity in the abdominal region with stretch marks. The respiratory examination is within normal limits. The cardiovascular exam is significant for a bilateral carotid bruit. The neurological examination shows bilateral decreased ankle reflex, symmetrically decreased touch sensation and absent vibration sensation in both feet up to the ankle. The gait is mildly ataxic. The Romberg test is positive with a tendency to fall to both sides, and significant worsening on eye closure. Which of the following medications should be used to manage the patient’s pain?", "answer": "Nortriptyline", "options": {"A": "Diclofenac", "B": "Morphine", "C": "Tramadol", "D": "Topiramate", "E": "Nortriptyline"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-year-old boy is brought to the pediatrician in the month of January with a one-week history of a cough and somnolence. He developed a fever and cough and stated that his legs hurt ‘really bad’ 3–4 days prior to his symptoms. He has asthma but no other significant past medical history. He takes albuterol and his mom administered acetaminophen because he was feeling ‘hot’. The blood pressure is 92/66 mm Hg, the heart rate is 118/min, the respiratory rate is 40/min, and the temperature is 39.2°C (102.6°F). On physical examination, the visualization of the pharynx shows mild erythema without purulence. Auscultation of the lungs reveals crackles over the right lung base. The rapid strep test is negative. A chest X-ray shows homogenous opacity in the lower lobe of the right lung. Which of the following best describes the vaccine that could have prevented the boy from acquiring this infection?", "answer": "Inactivated vaccine", "options": {"A": "Live attenuated vaccine", "B": "Inactivated vaccine", "C": "Subunit vaccine", "D": "Conjugate vaccine", "E": "Toxoid vaccine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3-month-old African American infant presents to the hospital with 2 days of fever, \"coke\"-colored urine, and jaundice. The pregnancy was uneventful except the infant was found to have hyperbilirubinemia that was treated with phototherapy. The mother explains that she breastfeeds her child and recently was treated herself for a UTI with trimethoprim-sulfamethoxazole (TMP-SMX). Which of the following diseases is similarly inherited as the disease experienced by the child?", "answer": "Hemophilia A", "options": {"A": "Marfan syndrome", "B": "Sickle cell anemia", "C": "Hemophilia A", "D": "Beta thalassemia", "E": "Rett syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 83-year-old male presents with dyspnea, orthopnea, and a chest radiograph demonstrating pulmonary edema. A diagnosis of congestive heart failure is considered. The following clinical measurements are obtained: 100 bpm heart rate, 0.2 mL O2/mL systemic blood arterial oxygen content, 0.1 mL O2/mL pulmonary arterial oxygen content, and 400 mL O2/min oxygen consumption. Using the above information, which of the following values represents this patient's cardiac stroke volume?", "answer": "40 mL/beat", "options": {"A": "30 mL/beat", "B": "40 mL/beat", "C": "50 mL/beat", "D": "60 mL/beat", "E": "70 mL/beat"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 67-year-old man presents with an excruciatingly painful tongue lesion. He says the lesion was preceded by an intermittent headache for the past month that localized unilaterally to the left temple and occasionally radiates to the right eye. The tongue lesion onset acutely and has been present for a few days. The pain is constant. His past medical history is relevant for hypertension and recurrent migraines. Current medications include captopril. On physical examination, multiple knot-like swellings are seen on the left temple. Findings from an inspection of the oral cavity are shown in the exhibit (see image). Laboratory findings are significant for the following:\nHemoglobin 12.9 g/dL\nHematocrit 40.7%\nLeukocyte count 5500/mm3\nNeutrophils 65%\nLymphocytes 30%\nMonocytes 5%\nMean corpuscular volume 88.2 μm3\nPlatelet count 190,000/mm3\nErythrocyte sedimentation rate 45 mm/h\nWhich of the following is the next best step in the management of this patient?", "answer": "High-dose systemic corticosteroids", "options": {"A": "Temporal artery biopsy", "B": "CT", "C": "Lysis therapy", "D": "High-dose systemic corticosteroids", "E": "Paracetamol"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old man presents to his primary care physician for a wellness checkup. The patient states he has been doing well and currently has no concerns. The patient's daughter states that she feels he is abnormally fatigued and has complained of light-headedness whenever he gardens. He also admits that he fainted once. The patient has a past medical history of type II diabetes, hypertension, and constipation. He recently had a \"throat cold\" that he recovered from with rest and fluids. His temperature is 98.9°F (37.2°C), blood pressure is 167/98 mmHg, pulse is 90/min, respirations are 12/min, and oxygen saturation is 99% on room air. Physical exam reveals a systolic murmur heard best along the right upper sternal border. An ECG is performed and demonstrates no signs of ST elevation. Cardiac troponins are negative. Which of the following is the most likely diagnosis?", "answer": "Calcification of valve leaflets", "options": {"A": "Autoimmune valve destruction", "B": "Bicuspid valve", "C": "Calcification of valve leaflets", "D": "Incompetent valve", "E": "Outflow tract obstruction"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old woman presents to the office complaining of leg ulcers for the past 6 months. She has a chronic history of severe rheumatoid arthritis controlled with methotrexate. She does not drink alcohol or smoke cigarettes. Her vitals are normal. Her lungs are clear to auscultation. The abdomen is soft and non-tender with a palpable spleen tip on inspiration. Skin examination shows scattered ulcers on the legs in various stages of healing. Additionally, metacarpophalangeal and proximal interphalangeal joints are tender. Varicose veins are not observed. Laboratory results are as follows:\nHemoglobin  10.5 g/dL\nMCV 74 fl\nPlatelets 226,000/mm3\nWhite blood cells 2500 /mm3\nNeutrophils 20%\nAlanine 36/UL\nAminotransaminase aspartate 39/UL\nAminotransaminase creatinine 1.0 mg/dL\nHIV test is negative. Which of the following is the most likely cause of this patient’s condition?", "answer": "Felty syndrome", "options": {"A": "Venous stasis and valve insufficiency", "B": "Felty syndrome", "C": "Drug toxicity", "D": "Vitamin deficiency", "E": "Caplan syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 10-day-old infant is brought to the emergency department by his mother because of episodes of weakness and spasms for the past 12 hours. His mother states that he has also had difficulty feeding and a weak suck. He has not had fever, cough, diarrhea, or vomiting. He was born at 39 weeks' gestation via uncomplicated vaginal delivery at home. Pregnancy was uncomplicated. The mother refused antenatal vaccines out of concern they would cause side effects. She is worried his symptoms may be from some raw honey his older sister maybe inadvertently fed him 5 days ago. He appears irritable. His temperature is 37.1°C (98.8°F). Examination shows generalized muscle stiffness and twitches. His fontanelles are soft and flat. The remainder of the examination shows no abnormalities. Which of the following is the most likely causal organism?", "answer": "Clostridium tetani", "options": {"A": "Clostridium botulinum", "B": "Clostridium tetani", "C": "Neisseria meningitidis", "D": "Listeria monocytogenes", "E": "Escherichia coli\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old girl is brought to the clinic by her parents, who are concerned about an abdominal swelling that they noticed 2 days ago. The family immigrated from Bangladesh to the United States recently. The mother mentions that the girl has never been as active as other children of the same age but has no medical conditions either. Her appetite has declined, and she vomited a few times last week. On physical examination, slight prominence of frontal bosses at the forehead is noticeable with malar prominence and massive splenomegaly. Slight beading at the end of her ribs is evident. She has a dusky complexion, sclerae are anicteric, and oral mucosa is pale. Laboratory results are pending. Which of the following is the most likely explanation for the findings seen in this patient?", "answer": "Extramedullary hematopoiesis due to thalassemia", "options": {"A": "Glycogen storage disease", "B": "Graves disease", "C": "Renal failure", "D": "Extramedullary hematopoiesis due to thalassemia", "E": "Lymphoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 14-year-old boy presents to his pediatrician with a 5-day history of abdominal pain and bloody stool. He denies having a fever and says that he has not experienced any other symptoms associated with the abdominal pain. He has no past medical history and does not take any medications or supplements. His family history is significant for a grandfather who developed Alzheimer disease at age 80 and a cousin who died at age 21 from colon cancer. Physical exam is unremarkable. Based on clinical suspicion a colonoscopy is obtained showing hundreds of small polyps in the colon. A mutation of a gene on which of the following chromosomes is most likely responsible for this patient's symptoms?", "answer": "5", "options": {"A": "5", "B": "7", "C": "17", "D": "19", "E": "X"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old man comes to the physician because of pain, tingling, and numbness in his right hand that started 3 months ago. It is worse at night and frequently wakes him up. The symptoms can be relieved by shaking his hands but soon recur. He reports weakness of his right hand, especially when grasping objects. He has type 2 diabetes mellitus. His current medications are metformin and sitagliptin. Four months ago he went on a camping trip. He has been working as a hardscaper for 8 years. His temperature is 37.5°C (99.5°F), pulse is 86/min, and blood pressure is 110/70 mm Hg. Examination shows reproduction of his symptoms when his right hand is held above his head for 2 minutes. Laboratory studies show:\nHemoglobin 13.2 g/dL\nLeukocyte count 7,600/mm3\nHemoglobin A1C 6.3%\nErythrocyte sedimentation rate 13 mm/h\nWhich of the following is most likely to confirm the diagnosis?\"", "answer": "Nerve conduction studies", "options": {"A": "ELISA for B. burgdorferi antibodies", "B": "CT scan of cervical spine", "C": "Nerve conduction studies", "D": "MRI of the head", "E": "Arterial Doppler ultrasonography\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 64-year-old man comes to the physician because of fatigue and decreased urinary frequency for 6 months. His pulse is 86/min and blood pressure is 150/90 mm Hg. Examination shows 1+ edema on bilateral ankles. His serum creatinine is 2 mg/dL and blood urea nitrogen is 28 mg/dL. Urinalysis shows proteinuria. A photomicrograph of a biopsy specimen from the patient's kidney is shown. Which of the following is the most likely explanation for the patient’s biopsy findings?", "answer": "Chronic hyperglycemia", "options": {"A": "HIV infection", "B": "Amyloidosis", "C": "Chronic hyperglycemia", "D": "Recurrent kidney infections", "E": "Systemic lupus erythematosus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old woman comes to the physician for a routine health maintenance examination. She has no personal or family history of serious illness. She smoked one pack of cigarettes daily for 5 years during her 20s. Her pulse is 70/min, and blood pressure is 120/78 mm Hg. Serum lipid studies and glucose concentration are within the reference ranges. Which of the following health maintenance recommendations is most appropriate at this time?", "answer": "Perform colonoscopy", "options": {"A": "Perform DEXA scan", "B": "Perform colonoscopy", "C": "Perform 24-hour ECG", "D": "Perform BRCA gene test", "E": "Perform abdominal ultrasound"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old man presents to the emergency department when he discovered a large volume of blood in his stool. He states that he was going to the bathroom when he saw a large amount of bright red blood in the toilet bowl. He was surprised because he did not feel pain and felt it was a normal bowel movement. The patient has a past medical history of diabetes, obesity, hypertension, anxiety, fibromyalgia, diabetic nephropathy, and schizotypal personality disorder. His current medications include atorvastatin, lisinopril, metformin, insulin, clonazepam, gabapentin, sodium docusate, polyethylene glycol, fiber supplements, and ibuprofen. His temperature is 99.5°F (37.5°C), blood pressure is 132/84 mmHg, pulse is 80/min, respirations are 11/min, and oxygen saturation is 96% on room air. On physical exam, the patient's cardiac exam reveals a normal rate and rhythm, and his pulmonary exam is clear to auscultation bilaterally. Abdominal exam is notable for an obese abdomen without tenderness to palpation. Which of the following is an appropriate treatment for this patient's condition?", "answer": "IV fluids and NPO", "options": {"A": "Cautery of an arteriovenous malformation", "B": "IV fluids and NPO", "C": "NPO, ciprofloxacin, and metronidazole", "D": "Surgical excision of poorly differentiated tissue", "E": "Surgical resection of a blood vessel"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A popular news outlet recently published an article that discussed the size of low-density lipoprotein (LDL) cholesterol particles: type A and type B. Type B is thought to be more harmful to arterial walls. A group of researchers wants to determine whether patients who have an elevated level of type B LDL cholesterol are more likely to develop cardiovascular events. A study is designed with 3418 adult participants. Initial levels of type B LDL are obtained and participants are separated into normal and elevated levels of type B LDL. Socio-demographics including age, gender, education level, and smoking status are also recorded. The primary outcome is incidence of cardiovascular events over 10 years. Secondary outcomes include all-cause death, death by cardiovascular events, stroke, and hospitalizations. For this study, which of the following analyses would be the most appropriate measure to determine the association between type B LDL and cardiovascular events?", "answer": "Relative risk", "options": {"A": "Analysis of covariance", "B": "Fisher’s exact test", "C": "Likelihood ratios", "D": "Odds ratio", "E": "Relative risk"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old man comes to the emergency department for the evaluation of recurrent bloody diarrhea for 4 weeks. During this time, he has also had intermittent abdominal pain. His symptoms have worsened over the past 2 days and he has also had fever and several episodes of nonbloody vomiting. He was diagnosed with ulcerative colitis three years ago but has had difficulty complying with his drug regimen. His temperature is 38.8°C (100.9°F), pulse is 112/min and regular, and blood pressure is 90/50 mm Hg. Abdominal examination shows a distended abdomen with no guarding or rebound; bowel sounds are hypoactive. Hemoglobin concentration is 10.1 g/dL, leukocyte count is 15,000/mm3, and erythrocyte sedimentation rate is 50 mm/h. Fluid resuscitation is initiated. In addition to complete bowel rest, which of the following is the most appropriate next step in the management of this patient?", "answer": "Abdominal x-ray", "options": {"A": "Topical sulfasalazine and oral prednisolone", "B": "Abdominal x-ray", "C": "IV metronidazole and rectal vancomycin", "D": "Double-contrast barium enema", "E": "Colonoscopy\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 19-year-old woman, gravida 1, para 0, at 21 weeks’ gestation comes to the physician for a follow-up prenatal visit. At her previous appointment, her serum α-fetoprotein concentration was elevated. She had smoked 1 pack of cigarettes daily for 3 years but quit at 6 weeks' gestation. Examination shows a uterus consistent in size with a 21-week gestation. Ultrasonography shows fetal viscera suspended freely into the amniotic cavity. Which of the following is the most likely diagnosis?", "answer": "Gastroschisis", "options": {"A": "Diaphragmatic hernia", "B": "Umbilical hernia", "C": "Vesicourachal diverticulum", "D": "Gastroschisis", "E": "Omphalocele"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A mother brings her 10 month-old boy to the pediatrician for a check-up. His birth was without complications and his development to-date has been progressing normally. He currently crawls, pulls himself up to standing, says 'mama' and 'dada' nonspecifically, and responds when called by his name. However, his mother is concerned, as she has noted over the past several weeks that he has periods where he stops breathing when he gets frightened or upset. These episodes last for 20-30 seconds and are accompanied by his lips and face become bluish. His breathing has always resumed normally within 45 seconds after the start of the episode, and he acts normally afterwards. One instance resulted in the child passing out for a 5-10 seconds before a spontaneous recovery. Which of the following is the most appropriate management of this patient's condition?", "answer": "Education and reassurance of the mother", "options": {"A": "Education and reassurance of the mother", "B": "Echocardiogram", "C": "Electroencephalogram", "D": "Basic metabolic panel", "E": "Lung spirometry"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "  An outbreak of diphtheria has occurred for the third time in a decade in a small village in South Africa. Diphtheria is endemic to the area with many healthy villagers colonized with different bacterial strains. Vaccine distribution in this area is difficult due to treacherous terrain. A team of doctors is sent to the region to conduct a health campaign. Toxigenic strains of C. diphtheria are isolated from symptomatic patients. Which of the following best explains the initial emergence of a pathogenic strain causing such outbreaks?", "answer": "Lysogenic conversion", "options": {"A": "Presence of naked DNA in the environment", "B": "Infection with a lytic phage", "C": "Lysogenic conversion", "D": "Suppression of lysogenic cycle", "E": "Conjugation between the toxigenic and non-toxigenic strains of C. diphtheriae"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 39-year-old man presents to the emergency department for severe abdominal pain. His pain is located in the epigastric region of his abdomen, which he describes as sharp and persistent. His symptoms began approximately 2 days prior to presentation, and he has tried acetaminophen and ibuprofen, which did not improve his symptoms. He feels nauseated and has had 2 episodes of non-bloody, non-bilious emesis. He has a medical history of hypertension and hyperlipidemia for which he is on chlorthalidone and simvastatin. He has smoked 1 pack of cigarettes per day for the last 20 years and drinks 1 pint of vodka per day. On physical exam, there is tenderness to palpation of the upper abdomen, and the patient is noted to have tender hepatomegaly. Serum studies demonstrate:\n\nAmylase: 350 U/L (25-125 U/L)\nLipase: 150 U/L (12-53 U/L)\nAST: 305 U/L (8-20 U/L)\nALT: 152 U/L (8-20 U/L)\n\nHe is admitted to the hospital and started on intravenous fluids and morphine. Approximately 18 hours after admission the patient reports to feeling anxious, tremulous, and having trouble falling asleep. His blood pressure is 165/105 mmHg and pulse is 140/min. On exam, the patient appears restless and diaphoretic. Which of the following will most likely improve this patient's symptoms?", "answer": "Lorazepam", "options": {"A": "Chlordiazepoxide", "B": "Haloperidol", "C": "Lorazepam", "D": "Risperidone", "E": "Thiamine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 41-year-old African American man presents to his primary care physician a few months after being found to have a blood pressure of 152/95 mmHg. The patient denies any current symptoms, having any past medical history, or prior hospitalizations. He does not take any medications but takes one multivitamin daily. His blood pressures on three separate occasions have been 151/93 mmHg, 150/90 mmHg, and 155/97 mmHg. In today’s visit, his blood pressure is 149/91 mmHg despite exercise and dietary modifications. Physical examination is unremarkable. After extensive work-up he is started on appropriate monotherapy for his hypertension. Which of the following laboratory abnormalities may be found on follow-up testing?", "answer": "Hypercalcemia", "options": {"A": "Hypercalcemia", "B": "Hyperkalemia", "C": "Hypermagnesemia", "D": "Hypolipidemia", "E": "Hypouricemia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 11-year-old boy presents to the emergency department with heavy drooling. The patient was being watched by his babysitter when she found him in this manner. His temperature is 99.1°F (37.3°C), blood pressure is 107/58 mmHg, pulse is 119/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam is notable for a young boy in acute distress who is drooling. The boy states he is in pain and can’t swallow. The patient’s tongue seems abnormally enlarged and erythematous. Which of the following is the most likely diagnosis?", "answer": "Caustic ingestion", "options": {"A": "Aspirin overdose", "B": "Caustic ingestion", "C": "Diphenhydramine ingestion", "D": "Insecticide exposure", "E": "Iron overdose"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 66-year-old man is brought to the emergency department because of shortness of breath and confusion. His pulse is 98/min, and blood pressure is 109/73 mm Hg. He is oriented to person but not time or place. A graph of his breathing pattern and oxygen saturation is shown. Which of the following additional findings is most likely present in this patient?", "answer": "Ventricular gallop", "options": {"A": "Ventricular gallop", "B": "Rib fracture", "C": "Miotic pupils", "D": "Barrel chest", "E": "Fruity breath odor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A patient in the neonatal intensive care unit develops severe cyanosis. Cardiac exam reveals a single loud S2 with a right ventricular heave. Echocardiography reveals an aorta lying anterior and right of the pulmonary artery. Which of the following processes failed during fetal development?", "answer": "Aorticopulmonary septum to spiral", "options": {"A": "Fusion of the membranous ventricular septum", "B": "Aorticopulmonary septum to spiral", "C": "Ectopic ductal tissue tightening", "D": "Reentry of viscera from yolk sac", "E": "Fusion of septum primum and septum secondum"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-year-old boy is brought to the emergency department late at night by his worried mother. She says he has not been feeling well since this morning after breakfast. He skipped both lunch and dinner. He complains of abdominal pain as he points towards his lower abdomen but says that the pain initially started at the center of his belly. His mother adds that he vomited once on the way to the hospital. His past medical history is noncontributory and his vaccinations are up to date. His temperature is 38.1°C (100.6°F), pulse is 98/min, respirations are 20/min, and blood pressure is 110/75 mm Hg. Physical examination reveals right lower quadrant tenderness. The patient is prepared for laparoscopic abdominal surgery. Which of the following structures is most likely to aid the surgeons in finding the source of this patient's pain and fever?", "answer": "Teniae coli", "options": {"A": "Teniae coli", "B": "McBurney's point", "C": "Transumbilical plane", "D": "Linea Semilunaris", "E": "Arcuate line"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 58-year-old woman is followed in the nephrology clinic for longstanding chronic kidney disease (CKD) secondary to uncontrolled hypertension. Her glomerular filtration rate (GFR) continues to decline, and she is approaching initiation of hemodialysis. Plans are made to obtain vascular access at the appropriate time, and the patient undergoes the requisite screening to be enrolled as an end stage renal disease (ESRD) patient. Among patients on chronic hemodialysis, which of the following is the most common cause of death?", "answer": "Cardiovascular disease", "options": {"A": "Stroke", "B": "Hyperkalemia", "C": "Infection", "D": "Cardiovascular disease", "E": "Cancer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old woman is brought to her primary care physician by her sister who is concerned about a deterioration in the patient’s general status. The patient was diagnosed with HIV 7 years ago. She says that her last T cell count was \"good enough\", so she has been been skipping every other dose of her antiretroviral medications and trimethoprim-sulfamethoxazole. Her sister has had to drive her home from work several times this month because she has become disoriented and confused about her surroundings. Motor strength is 4/5 on the right and 3/5 on the left. She is able to walk unassisted, but her gait appears mildly uncoordinated. There is diplopia when the right eye is covered. Her CD4 count is 75 cells/µL. MRI shows numerous asymmetric, hyperintense, non-enhancing lesions bilaterally without mass effect. Brain biopsy shows demyelination and atypical astrocytes. Which of the following is most likely responsible for this patient's current condition?", "answer": "John Cunningham virus (JC virus)", "options": {"A": "Autoimmune demyelination", "B": "HIV associated neurocognitive disorder (HAND)", "C": "John Cunningham virus (JC virus)", "D": "Primary CNS lymphoma (PCNSL)", "E": "Toxoplasma gondii"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old forest landscape specialist is brought to the emergency department with hematemesis and confusion. One week ago, she was diagnosed with influenza when she had fevers, severe headaches, myalgias, hip and shoulder pain, and a maculopapular rash. After a day of relative remission, she developed abdominal pain, vomiting, and diarrhea. A single episode of hematemesis occurred prior to admission. Two weeks ago she visited rainforests and caves in western Africa where she had direct contact with animals, including apes. She has no history of serious illnesses or use of medications. She is restless and her temperature is 38.0°C (100.4°F); pulse, 95/min; respirations, 20/min; and supine and upright blood pressure, 130/70 mm Hg and 100/65 mm Hg, respectively. Conjunctival suffusion is seen. Ecchymoses are observed on the lower extremities. She is bleeding from one of her intravenous lines. The peripheral blood smear is negative for organisms. The laboratory studies show the following:\nHemoglobin 10 g/dL\nLeukocyte count 1,000/mm3\nSegmented neutrophils 65%\nLymphocytes 20%\nPlatelet count 50,000/mm3\nPartial thromboplastin time (activated) 60 seconds\nProthrombin time 25 seconds\nFibrin split products positive\nSerum  \nAlanine aminotransferase (ALT) 85 U/L\nAspartate aminotransferase (AST) 120 U/L\nγ-Glutamyltransferase (GGT) 83 U/L (N = 5–50 U/L)\nCreatinine 2 mg/dL\nWhich of the following is the most likely causal pathogen?", "answer": "Ebola virus", "options": {"A": "Ebola virus", "B": "Babesia microti", "C": "Plasmodium falciparum", "D": "Yersinia pestis", "E": "Zika virus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 10-year-old child is sent to the school psychologist in May because he refuses to comply with the class rules. His teacher says this has been going on since school started back in August. He gets upset at the teacher regularly when he is told to complete a homework assignment in class. Sometimes he refuses to complete them altogether. Several of his teachers have reported that he intentionally creates noises in class to interrupt the class. He tells the psychologist that the teacher and his classmates are at fault. What is the most appropriate treatment?", "answer": "Cognitive-behavioral therapy", "options": {"A": "Administration of clozapine", "B": "Administration of lithium", "C": "Cognitive-behavioral therapy", "D": "Interpersonal therapy", "E": "Motivational interviewing"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to the physician by his parents for the evaluation of an episode of loss of consciousness while he was playing soccer earlier that morning. He was unconscious for about 15 seconds and did not shake, bite his tongue, or lose bowel or bladder control. He has been healthy except for 1 episode of simple febrile seizure. His father died suddenly at the age of 34 of an unknown heart condition. The patient does not take any medications. He is alert and oriented. His temperature is 37°C (98.6°F), pulse is 95/min and regular, and blood pressure is 90/60 mm Hg. Physical examination shows no abnormalities. Laboratory studies are within normal limits. An ECG shows sinus rhythm and a QT interval corrected for heart rate (QTc) of 470 milliseconds. Which of the following is the most appropriate next step in treatment?", "answer": "Propranolol", "options": {"A": "Propranolol", "B": "Implantable cardioverter defibrillator", "C": "Procainamide", "D": "Magnesium sulfate", "E": "Amiodarone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 9-year-old boy is brought to the emergency department by his mother because of painful swelling in his right knee that started after he collided with another player during a soccer game. He has no history of serious illness except for an episode of prolonged bleeding following a tooth extraction a few months ago. Physical examination shows marked tenderness and swelling of the right knee joint. There are multiple bruises on the lower extremities in various stages of healing. Laboratory studies show a platelet count of 235,000/mm3, partial thromboplastin time of 78 seconds, prothrombin time of 14 seconds, and bleeding time of 4 minutes. The plasma concentration of which of the following is most likely to be decreased in this patient?", "answer": "Thrombin", "options": {"A": "Protein C", "B": "Plasmin", "C": "Thrombin", "D": "Von Willebrand factor", "E": "Factor VII"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old woman presents with dysphagia. She says the dysphagia is worse for solids than liquids and is progressive. She also complains of associated weakness, fatigue, and dyspnea. The patient denies any recent history of weight loss. Laboratory findings are significant for a hemoglobin of 8.7 g/dL. A peripheral blood smear shows evidence of microcytic hypochromic anemia. Which of the following is the most likely cause of her dysphagia?", "answer": "Upper esophageal web", "options": {"A": "Lower esophageal ring", "B": "Failure of the relaxation of lower esophageal sphincter", "C": "Upper esophageal web", "D": "Lower esophageal spasm", "E": "Esophageal carcinoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 16-year-old girl is brought to the physician because of a 1-month history of fever, headaches, and profound fatigue. Her temperature is 38.2°C (100.8°F). Examination shows splenomegaly. Laboratory studies show:\nLeukocyte count 13,000/mm3 (15% atypical lymphocytes)\nSerum\nAlanine aminotransferase (ALT) 60 U/L\nAspartate aminotransferase (AST) 40 U/L\nHeterophile antibody assay negative\nEBV viral capsid antigen (VCA) antibodies negative\nHIV antibody negative\nIn an immunocompromised host, the causal organism of this patient's symptoms would most likely cause which of the following conditions?\"", "answer": "Linear ulcers near the lower esophageal sphincter", "options": {"A": "Multiple cerebral abscesses with surrounding edema", "B": "Diffuse pulmonary infiltrates with pneumatoceles", "C": "Purplish skin nodules on the distal extremities", "D": "Non-scrapable white patches on the lateral tongue", "E": "Linear ulcers near the lower esophageal sphincter"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old African American woman presents to her primary care physician for a wellness checkup. She states that she has lost 20 pounds over the past 2 months yet has experienced an increased appetite during this period. She endorses hyperhidrosis and increased urinary volume and frequency. Physical exam is notable for an anxious woman and a regular and tachycardic pulse. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nCa2+: 12.2 mg/dL\n\nThe patient's urine calcium level is elevated. Which of the following is the most likely diagnosis?", "answer": "Hyperthyroidism", "options": {"A": "Familial hypercalcemic hypocalciuria", "B": "Hyperparathyroidism", "C": "Hyperthyroidism", "D": "Malignancy", "E": "Sarcoidosis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 57-year-old woman comes to the emergency department because of dizziness, nausea, and vomiting for 4 days. Her temperature is 37.3°C (99.1°F), pulse is 100/min, respirations are 20/min, and blood pressure is 110/70 mm Hg. Physical examination shows no abnormalities. Arterial blood gas analysis on room air shows:\npH 7.58\nPCO2 43 mm Hg\nPO2 96 mm Hg\nHCO3- 32 mEq/L\nThe most appropriate next step in diagnosis is measurement of which of the following?\"", "answer": "Urine chloride", "options": {"A": "Urine albumin to creatinine ratio", "B": "Serum osmolal gap", "C": "Urine chloride", "D": "Urine anion gap", "E": "Serum anion gap"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old man comes to the physician because of low-grade fever and progressive painful lumps in his right groin for 6 days. The lumps have been discharging purulent fluid since the evening of the previous day. He had a shallow, painless lesion on his penis 3 weeks ago, but was too embarrassed to seek medical attention; it has resolved in the meantime. There is no personal or family history of serious illness. He has smoked one pack of cigarettes daily for 12 years. He is sexually active with multiple male partners and uses condoms inconsistently. His temperature is 38.0°C (100.4°F). Examination of his groin shows multiple masses discharging pus. The remainder of the examination shows no abnormalities. Which of the following is the most likely causal organism?", "answer": "Chlamydia trachomatis", "options": {"A": "Haemophilus ducreyi", "B": "Yersinia pestis", "C": "Herpes simplex virus 2", "D": "Klebsiella granulomatis", "E": "Chlamydia trachomatis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old woman comes to the physician for the evaluation of persistent headaches for the last 2 months. The symptoms started insidiously. Menses had previously occurred at regular 28-day intervals with moderate flow. Her last menstrual period was 12 weeks ago. She is sexually active with her husband but reports decreased interest in sexual intercourse over the past few months. The patient does not smoke or drink alcohol. She is 168 cm (5 ft 6 in) tall and weighs 68 kg (150 lb); BMI is 24 kg/m2. She appears uncomfortable. Vital signs are within normal limits. A urine pregnancy test is negative. A pelvic ultrasound shows atrophic endometrium. A cranial MRI with contrast shows a 2-cm intrasellar mass. A hormone assay is performed and is positive. Which of the following is the most appropriate next step in the management?", "answer": "Cabergoline therapy", "options": {"A": "Cabergoline therapy", "B": "Radiotherapy", "C": "Observation and outpatient follow-up", "D": "Biopsy of intrasellar mass", "E": "Temozolomide therapy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 69-year-old man presents to his primary care physician after 2 episodes of dizziness while watching television. On further questioning, he admits to progressive fatigue and shortness of breath on exertion for the past few weeks. His medical history is significant for hypertension for the past 25 years and congestive heart failure for the past 2 years, for which he is on multiple medications. His blood pressure is 100/50 mm Hg, the heart rate is 50/min, and the temperature is 36.6°C (97.8°F). The physical examination is within normal limits. A 12-lead ECG is obtained and the results are shown in the picture. Which of the following is the best initial step for the management of this patient?", "answer": "Check the patient's medication profile", "options": {"A": "Observation and repeat ECG if symptoms recur", "B": "Temporary cardiac pacing", "C": "External defibrillation", "D": "Check the patient's medication profile", "E": "Glucagon"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old woman comes to the physician because of increasingly frequent episodes of double vision for 2 days. She was seen in the emergency department for an episode of imbalance and decreased sensation in her right arm 3 months ago. Examination shows impaired adduction of the right eye with left lateral gaze but normal convergence of both eyes. Deep tendon reflexes are 4+ in all extremities. The Romberg test is positive. An MRI of the brain shows hyperintense oval plaques in the periventricular region and a plaque in the midbrain on T2-weighted images. Microscopic examination of material from the midbrain plaque would most likely show which of the following?", "answer": "Demyelination with partial preservation of axons\n\"", "options": {"A": "Eosinophilic intracytoplasmic inclusion bodies", "B": "Loss of axons and atrophy of oligodendrocytes", "C": "Lymphocytic infiltration of the endoneurium", "D": "Extracellular deposits of amyloid peptides", "E": "Demyelination with partial preservation of axons\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old woman is brought to the emergency department by police after being found naked outside a government building. She is accompanied by her husband who reports that she has been having “crazy” ideas. The patient’s speech is pressured and she switches topics quickly from how she is going to be president one day to how she is going to learn 20 languages fluently by the end of the year. Upon further questioning, it is revealed that she has struggled with at least 2 depressive episodes in the past year. Her medical history is significant for hypertension, hyperlipidemia, gout, and chronic migraines. She was recently diagnosed with a urinary tract infection and given nitrofurantoin. She has also been taking indomethacin for an acute gout flare. Her other medications include atorvastatin, allopurinol, metoprolol, and acetazolamide. She is prescribed lithium and instructed to follow-up with a primary care physician. At a follow-up appointment, she complains of nausea, vomiting, and increased urinary frequency. On examination, she has a coarse tremor and diffuse hyperreflexia. Which of the following medications is most likely is responsible for the patient’s current presentation?", "answer": "Indomethacin", "options": {"A": "Acetazolamide", "B": "Atorvastatin", "C": "Indomethacin", "D": "Metoprolol", "E": "Nitrofurantoin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old Caucasian woman visits her primary care physician for an annual check-up. She has a history of type 2 diabetes mellitus and stage 3A chronic kidney disease. Her estimated glomerular filtration rate has not changed since her last visit. Today, her parathyroid levels are moderately elevated. She lives at home with her husband and 2 children and works as a bank clerk. Her vitals are normal, and her physical examination is unremarkable. Which of the following explains this new finding?", "answer": "Phosphate retention", "options": {"A": "Phosphate retention", "B": "Hyperuricemia", "C": "Acidemia", "D": "Hypercalcemia", "E": "Uremia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old woman presents with a severe headache and neck pain for the past 60 minutes. She says the headache was severe and onset suddenly like a ‘thunderclap’. She reports associated nausea, vomiting, neck pain, and stiffness. She denies any recent head trauma, loss of consciousness, visual disturbances, or focal neurologic deficits. Her past medical history is significant for hypertension, managed with hydrochlorothiazide. She denies any history of smoking, alcohol use, or recreational drug use. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 165/95 mm Hg, pulse 92/min, and respiratory rate 15/min. On physical examination, there is mild nuchal rigidity noted with limited flexion at the neck. An ophthalmic examination of the retina shows mild papilledema. A noncontrast computed tomography (CT) scan of the head is performed and shown in the exhibit (see image). Which of the following is the next best step in the management of this patient?", "answer": "Labetalol", "options": {"A": "Mannitol", "B": "Lumbar puncture", "C": "Nitroprusside", "D": "Dexamethasone", "E": "Labetalol"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old primigravida presents to her physician’s office at 35 weeks gestation with new onset lower leg edema. The course of her pregnancy was uneventful up to the time of presentation and she has been compliant with the recommended  prenatal care. She reports a 4 pack-year history of smoking prior to her pregnancy. She also used oral contraceptives for birth control before considering the pregnancy. Prior to pregnancy, she weighed 52 kg (114.6 lb). She gained 11 kg (24.3 lb) during the pregnancy thus far, and  2 kg (4.4 lb) during the last 2 weeks. Her height is 169 cm (5 ft 7 in). She has a family history of hypertension in her mother (diagnosed at 46 years of age) and aunt (diagnosed at 51 years of age). The blood pressure is 145/90 mm Hg, the heart rate is 91/min, the respiratory rate is 15/min, and the temperature is 36.6℃ (97.9℉). The blood pressure is unchanged 15 minutes and 4 hours after the initial measurement. The fetal heart rate is 144/min. The examination is remarkable for 2+ pitting lower leg edema. The neurologic examination shows no focality. A urine dipstick test shows 2+ proteinuria. Which of the following factors is a risk factor for her condition?", "answer": "Primigravida", "options": {"A": "Smoking prior to pregnancy", "B": "Oral contraceptives intake", "C": "Primigravida", "D": "BMI < 18.5 kg/m2 prior to pregnancy", "E": "Family history of hypertension"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old African American woman presents to her primary care doctor complaining of muscle aches and weakness. She reports a 3 month history of gradually worsening upper and lower extremity pain. She is having trouble keeping up with her children and feels tired for most of the day. A review of systems reveals mild constipation. Her past medical history is notable for hypertension, diabetes, rheumatoid arthritis, and obesity. She takes lisinopril, metformin, and methotrexate. Her family history is notable for chronic lymphocytic leukemia in her mother and prostate cancer in her father. Her temperature is 99°F (37.2°C), blood pressure is 145/95 mmHg, pulse is 80/min, and respirations are 17/min. On exam, she appears well and in no acute distress. Muscle strength is 4/5 in her upper and lower extremities bilaterally. Patellar and brachioradialis reflexes are 2+ bilaterally. A serum analysis in this patient would most likely reveal which of the following?", "answer": "Increased PTH, decreased phosphate, and increased calcium", "options": {"A": "Decreased PTH, decreased phosphate, and increased calcium", "B": "Decreased PTH, increased phosphate, and decreased calcium", "C": "Increased PTH, decreased phosphate, and increased calcium", "D": "Increased PTH, increased phosphate, and decreased calcium", "E": "Increased PTH, increased phosphate, and increased calcium"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old girl presents to her pediatrician with complaints of repeated jerking of her neck for the past 2 years. Initially, her parents considered it a sign of discomfort in her neck, but later they noticed that the jerking was more frequent when she was under emotional stress or when she was fatigued. The patient says she can voluntarily control the jerking in some social situations, but when she is under stress, she feels the urge to jerk her neck and she feels better after that. The parents also report that during the past year, there have even been a few weeks when the frequency of the neck jerking had decreased drastically, only to increase again afterwards. On physical examination, she is a physically healthy female with normal vital signs. Her neurologic examination is normal. The pediatrician also notes that when he makes certain movements, the patient partially imitates these movements. The parents are very much concerned about her abnormal movements and insist on a complete diagnostic work-up. After a detailed history, physical examination, and laboratory investigations, the pediatrician confirms the diagnosis of Tourette syndrome. The presence of which of the following findings is most likely to confirm the pediatrician’s diagnosis?", "answer": "History of repeated bouts of unprovoked obscene speech over the past year", "options": {"A": "History of repeated bouts of unprovoked obscene speech over the past year", "B": "Rigidity and bradykinesia", "C": "Low serum ceruloplasmin level", "D": "Decreased caudate volumes in magnetic resonance imaging (MRI) of the brain", "E": "Increased activity in frontal subcortical regions in positron-emission tomography (PET) study"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "The division chief of general internal medicine at an academic medical center is interested in reducing 30-day readmissions for diabetic ketoacidosis (DKA) in elderly patients. Her research team decided to follow 587 patients over the age of 65 who have recently been admitted to the hospital for DKA for a 30-day period. At the end of 30 days, she identified 100 patients who were readmitted to the hospital and examined risk factors associated with readmission. The main results of her study are summarized in the table below.\nRR (95% CI) P-value\nEpisodes of DKA in the past 3 years < 0.001\nNone Reference\n1–2\n1.23 (1.04–1.36)\n3–4 1.48 (1.38–1.59)\n5+ 2.20 (1.83–2.51)\nWhich of the following aspects of the results would support a causal relationship between a history of DKA and 30-day readmission risk for DKA?\"", "answer": "Dose-response relationship", "options": {"A": "Low p-value", "B": "Confidence intervals that do not cross 1.0", "C": "Case-control study design", "D": "High odds ratio", "E": "Dose-response relationship"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 74-year-old man is brought from a nursing home to the emergency room for progressive confusion. The patient has a history of stroke 3 years ago, which rendered him wheelchair-bound. He was recently started on clozapine for schizothymia disorder. Vital signs reveal a temperature of 38.7°C (101.66°F), a blood pressure of 100/72 mm Hg, and a pulse of 105/minute. On physical examination, he is disoriented to place and time. Initial lab work-up results are shown:\nSerum glucose: 945 mg/dL\nSerum sodium: 120 mEq/L\nSerum urea: 58 mg/dL\nSerum creatinine: 2.2 mg/dL\nSerum osmolality: 338 mOsm/kg\nSerum beta-hydroxybutyrate: negative\nUrinalysis reveals: numerous white blood cells and trace ketones\nWhich of the following manifestations is more likely to be present in this patient?", "answer": "Seizures", "options": {"A": "Fruity odor of the breath", "B": "Abdominal pain", "C": "Seizures", "D": "Nausea or vomiting", "E": "Rapid deep breathing"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 54-year-old male presents to the emergency department with nasal congestion and sore throat. He also endorses ten days of fatigue, rhinorrhea and cough, which he reports are getting worse. For the last four days, he has also had facial pain and thicker nasal drainage. The patient’s past medical history includes obesity, type II diabetes mellitus, and mild intermittent asthma. His home medications include metformin and an albuterol inhaler as needed. The patient has a 40 pack-year smoking history and drinks 6-12 beers per week. His temperature is 102.8°F (39.3°C), blood pressure is 145/96 mmHg, pulse is 105/min, and respirations are 16/min. On physical exam, he has poor dentition. Purulent mucus is draining from his nares, and his oropharynx is erythematous. His maxillary sinuses are tender to palpation.\n\nWhich one of the following is the most common risk factor for this condition?", "answer": "Viral infection", "options": {"A": "Asthma", "B": "Diabetes mellitus", "C": "Poor dentition", "D": "Tobacco use", "E": "Viral infection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 72-year-old man presents to the emergency department with severe respiratory distress. He was diagnosed with metastatic pancreatic cancer 6 months ago and underwent 2 rounds of chemotherapy. He says that he has had a cough and flu-like symptoms for the past week. During the interview, he is having progressive difficulty answering questions and suddenly becomes obtunded with decreased motor reflexes. His temperature is 38.8°C (102.0°F), blood pressure is 90/60 mm Hg, pulse is 94/min, and respirations are 22/min. Pulse oximetry is 82% on room air. The patient’s medical record contains an advanced directive stating that he would like all interventions except for cardiopulmonary resuscitation. Which of the following is the most appropriate next step in management?", "answer": "Intubate and administer intravenous antibiotics.", "options": {"A": "Observe and monitor vital signs for improvement.", "B": "Administer intravenous fluids.", "C": "Intubate and administer intravenous antibiotics.", "D": "Administer intravenous antibiotics and draw blood for testing.", "E": "Intubate only."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old woman presents to clinic complaining of pelvic pain and heavy menstrual bleeding for the past 2 years. The patient reports that her last menstrual period was 1 week ago and she soaked through 1 tampon every 1-2 hours during that time. She does not take any medications and denies alcohol and cigarette use. She is currently trying to have a child with her husband. She works as a school teacher and exercises regularly. Her temperature is 97.0°F (36.1°C), blood pressure is 122/80 mmHg, pulse is 93/min, respirations are 16/min, and oxygen saturation is 99% on room air. Physical examination reveals an enlarged, irregularly-shaped uterus palpable at the level of the umbilicus. Laboratory studies are ordered as seen below.\n\nHemoglobin: 9.0 g/dL\nHematocrit: 29%\nMCV: 70 fL\nLeukocyte count: 4,500/mm^3 with normal differential\nPlatelet count: 188,000/mm^3\n\nUrine:\nhCG: Negative\nBlood: Negative\nLeukocytes: Negative\nBacteria: Negative\n\nWhich of the following is the most effective treatment for this patient?", "answer": "Myomectomy", "options": {"A": "Folate", "B": "Hysterectomy", "C": "Iron", "D": "Myomectomy", "E": "Oral contraceptive pills"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old man is brought to the emergency department by ambulance after a motor vehicle accident. His car was rear-ended by a drunk driver while he was stopped at a traffic light. At the scene, he was noted to have multiple small lacerations over his upper extremities from broken glass. He has otherwise been healthy, does not smoke, and drinks 5 beers per night. He notes that he recently started trying out a vegan diet and moved to an apartment located in a historic neighborhood that was built in the 1870s. Physical exam reveals several small lacerations on his arms bilaterally but is otherwise unremarkable. A complete blood workup is sent and some of the notable findings are shown below:\n\nHemoglobin: 12.1 g/dL (normal: 13.5-17.5 g/dL)\nPlatelet count: 261,000/mm^3 (normal: 150,000-400,000/mm^3)\nMean corpuscular volume: 74 µm^3 (normal: 80-100 µm^3)\n\nFurther testing using serum hemoglobin electrophoresis reveals:\nHemoglobin A1 92% (normal 95-98%)\nHemoglobin A2: 6% (normal: 1.5-3.1%)\n\nWhich of the following cell morphologies would most likely be seen on blood smear in this patient?", "answer": "Codocytes", "options": {"A": "All cells appear normal", "B": "Codocytes", "C": "Megaloblasts", "D": "Sideroblasts", "E": "Schistocytes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman comes to the physician because of a 3-month history of worsening fatigue. She has difficulty concentrating at work despite sleeping well most nights. Three years ago, she was diagnosed with Crohn disease. She has about 7 non-bloody, mildly painful bowel movements daily. Her current medications include 5-aminosalicylic acid and topical budesonide. She does not smoke or drink alcohol. She appears pale. Her temperature is 37.9°C (100.2°F), pulse is 92/min, and blood pressure is 110/65 mmHg. The abdomen is diffusely tender to palpation, with no guarding. Laboratory results show:\nHemoglobin 10.5 g/dL\nMean corpuscular volume 83 μm3\nReticulocytes 0.2 %\nPlatelets 189,000/mm3\nSerum\nIron 21 μg/dL\nTotal iron binding capacity 176 μg/dL (N=240–450)\nA blood smear shows anisocytosis. Which of the following is the most appropriate next step in treatment?\"", "answer": "Oral prednisone therapy", "options": {"A": "Oral prednisone therapy", "B": "Subcutaneous erythropoietin injection", "C": "Red blood cell transfusion", "D": "Intravenous metronidazole therapy", "E": "Oral vitamin B12 supplementation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 10-year-old girl with a rash is brought to the clinic by her mother. The patient’s mother says that the onset of the rash occurred 2 days ago. The rash was itchy, red, and initially localized to the cheeks with circumoral pallor, and it gradually spread to the arms and trunk. The patient’s mother also says her daughter had been reporting a high fever of 39.4°C (102.9°F), headaches, myalgia, and flu-like symptoms about a week ago, which resolved in 2 days with acetaminophen. The patient has no significant past medical history. Her vital signs include: temperature 37.0°C (98.6°F), pulse 90/min, blood pressure 125/85 mm Hg, respiratory rate 20/min. Physical examination shows a symmetric erythematous maculopapular rash on both cheeks with circumoral pallor, which extends to the patient’s trunk, arms, and buttocks. The remainder of the exam is unremarkable. Laboratory findings are significant for a leukocyte count of 7,100/mm3 and platelet count of 325,000/mm3. Which of the following is the next best step in the management of this patient?", "answer": "Discharge home, saying that the patient may immediately return to school", "options": {"A": "Administer intravenous immunoglobulin (IVIG)", "B": "Transfuse with whole blood", "C": "Discharge home, saying that the patient may immediately return to school", "D": "Discharge home, saying that the patient may return to school after the disappearance of the rash", "E": "Discharge home with instructions for strict isolation from pregnant women until disappearance of the rash"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 54-year-old male presents to the emergency department after an episode of bloody vomiting. He is a chronic alcoholic with a history of cirrhosis, and this is the third time he is presenting with this complaint. His first two episodes of hematemesis required endoscopic management of bleeding esophageal varices. His hemoglobin on admission laboratory evaluation was 11.2 g/dL. The patient is stabilized, and upper endoscopy is performed with successful banding of bleeding varices. Follow-up lab-work shows hemoglobin levels of 10.9 g/dL and 11.1 g/dL on days 1 and 2 after admission. Which of the following is the best next step in the management of this patient?", "answer": "Discuss with the patient the option of a transjugular intrahepatic portosystemic stent (TIPS)", "options": {"A": "Monitor stability and discharge with continuation of endoscopic surveillance at regular 3 month intervals", "B": "Discuss with the patient the option of a transjugular intrahepatic portosystemic stent (TIPS)", "C": "Balloon tamponade of bleeding varices", "D": "Begin long-term octreotide and a 4-week course of prophylactic antibiotics", "E": "Give 2 units packed RBCs"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man is brought into the emergency department after he was hit by a car. The patient was intoxicated and walked into oncoming traffic. He is currently unconscious and has a Glasgow coma scale score of 3. The patient has been admitted multiple times for alcohol intoxication and pancreatitis. The patient is resuscitated with fluid and blood products. An initial trauma survey reveals minor scrapes and abrasions and pelvic instability. The patient’s pelvis is placed in a binder. After further resuscitation the patient becomes responsive and states he is in pain. He is given medications and further resuscitation ensues. One hour later, the patient complains of numbness surrounding his mouth and in his extremities. Which of the following is the most likely explanation of this patient’s current symptoms?", "answer": "Transfusion complication", "options": {"A": "Hypokalemia", "B": "Late-onset edema surrounding the spinal cord", "C": "Medication complication", "D": "Transfusion complication", "E": "Trauma to the spinal cord"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 57-year-old woman is admitted to the intensive care unit for management of shock. Her pulse is feeble and blood pressure is 86/45 mm Hg. The patient undergoes pulmonary artery catheterization which shows an elevated pulmonary capillary wedge pressure and increased systemic vascular resistance. Which of the following additional findings is most likely in this patient?", "answer": "Confusion due to decreased stroke volume", "options": {"A": "Cold skin due to loss of intravascular fluid volume", "B": "Bradycardia due to neurologic dysfunction", "C": "Bronchospasm due to excessive histamine release", "D": "Mottled skin due to release of endotoxins", "E": "Confusion due to decreased stroke volume"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old Caucasian man presents to the emergency room with chest pain. Coronary angiography reveals significant stenosis of the left anterior descending (LAD) artery. Which of the following represents a plausible clinical predictor of myocardial necrosis in this patient?", "answer": "Rate of plaque formation", "options": {"A": "Cholesterol crystal presence", "B": "Rate of plaque formation", "C": "Calcium content", "D": "Presence of cytokines", "E": "Amount of foam cells"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old woman comes to the physician because of a 1-month history of intermittent abdominal pain, flatulence, and watery diarrhea. The episodes typically occur 2–3 hours after meals, particularly following ingestion of ice cream, cheese, and pizza. She is administered 50 g of lactose orally. Which of the following changes is most likely to be observed in this patient?", "answer": "Increased stool osmotic gap", "options": {"A": "Decreased urinary D-xylose concentration", "B": "Increased serum glucose concentration", "C": "Increased stool osmotic gap", "D": "Decreased fecal fat content", "E": "Decreased breath hydrogen content"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old male with a 10-year history of COPD visits his pulmonologist for a checkup. Physical examination reveals cyanosis, digital clubbing, and bilateral lung wheezes are heard upon auscultation. The patient has a cough productive of thick yellow sputum. Which of the following findings is most likely present in this patient?", "answer": "Increased pulmonary arterial resistance", "options": {"A": "Decreased arterial carbon dioxide content", "B": "Increased pulmonary arterial resistance", "C": "Increased pH of the arterial blood", "D": "Increased cerebral vascular resistance", "E": "Increased right ventricle compliance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Background and Methods:\nAldosterone is important in the pathophysiology of heart failure. In a double-blind study, we enrolled 1,663 patients who had severe heart failure, a left ventricular ejection fraction of no more than 35 percent, and were being treated with an angiotensin-converting-enzyme inhibitor, a loop diuretic, and in most cases digoxin. A total of 822 patients were randomly assigned to receive 25 mg of spironolactone daily and 841 to receive placebo. The primary endpoint was death from all causes.\nResults:\nThe trial was discontinued early, after a mean follow-up period of 24 months, because an interim analysis determined that spironolactone was efficacious. There were 386 deaths in the placebo group (46%) and 284 in the spironolactone group (35%; relative risk of death, 0.70; 95% confidence interval, 0.60 to 0.82; p<0.001). This 30 percent reduction in the risk of death among patients in the spironolactone group was attributed to a lower risk of both death from progressive heart failure and sudden death from cardiac causes. The frequency of hospitalization for worsening heart failure was 35% lower in the spironolactone group than in the placebo group (relative risk of hospitalization, 0.65; 95% confidence interval, 0.54 to 0.77; p<0.001). In addition, patients who received spironolactone had a significant improvement in the symptoms of heart failure, as assessed on the basis of the New York Heart Association functional class (p<0.001). Gynecomastia was reported in 10% of men who were treated with spironolactone, as compared with 1% of men in the placebo group (p<0.001). The incidence of serious hyperkalemia was minimal in both groups of patients.\nWhich of the following statements represents the most accurate interpretation of the results from the aforementioned clinical trial?", "answer": "Spironolactone, in addition to standard therapy, substantially reduces the risk of morbidity and death in patients with severe heart failure", "options": {"A": "Spironolactone, in addition to standard therapy, substantially reduces the risk of morbidity and death in patients with severe heart failure", "B": "The addition of spironolactone significant improved symptoms of heart failure, but not overall mortality", "C": "Spironolactone did not improve all-cause morbidity and mortality in patients with severe heart failure", "D": "The incidence of both gynecomastia and hyperkalemia was elevated in patients treated with spironolactone", "E": "Given the large sample size of this clinical trial, the results are likelily generalizable to all patient with heart failure"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "During an experiment, an investigator attempts to determine the rates of apoptosis in various tissue samples. Injecting cytotoxic T cells into the cell culture of one of the samples causes the tissue cells to undergo apoptosis. Apoptosis is most likely due to secretion of which of the following substances in this case?", "answer": "Granzyme B", "options": {"A": "Cytochrome C", "B": "Bcl-2", "C": "TNF-α", "D": "Granzyme B", "E": "Caspases"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Which of the following situations calls for treatment with alprazolam?", "answer": "A 35-year-old male that gets tachycardic, tachypnic, and diaphoretic every time he rides a plane", "options": {"A": "A 28-year-old female that gets irritated or worried about everyday things out of proportion to the actual source of worry", "B": "A 35-year-old male that gets tachycardic, tachypnic, and diaphoretic every time he rides a plane", "C": "A 42-year-old female with extreme mood changes ranging from mania to severe depression", "D": "A 19-year-old male that saw his sibling murdered, and has had flashbacks and hypervigilance for more than one month", "E": "A 65-year-old male with narrow angle glaucoma that complains of excessive worry, rumination, and uneasiness about future uncertainties"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old woman is brought to the clinic at her husband's insistence for sleep disturbances. Most nights of the week she repeatedly gets out of bed to pace around their apartment before returning to bed. The woman says that while she's lying in bed, she becomes overwhelmed by a \"creepy-crawly\" feeling in her legs that she can only relieve by getting out of bed. Past medical history is noncontributory and physical exam is unremarkable. Which of the following laboratory studies is most likely abnormal in this patient?", "answer": "Complete blood count", "options": {"A": "Complete blood count", "B": "Hemoglobin A1c", "C": "Liver function tests", "D": "Lumbar puncture", "E": "Nerve conduction studies"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 40-year-old woman presents with ongoing heartburn despite being on treatment for the last few months. She describes a burning sensation in her chest even after small meals. She has stopped eating fatty and spicy foods as they aggravate her heartburn significantly. She has also stopped drinking alcohol but is unable to quit smoking. Her attempts to lose weight have failed. Three months ago, she was started on omeprazole and ranitidine, but she still is having symptoms. She had previously used oral antacids but had to stop because of intolerable constipation. Past medical history is significant for a mild cough for the past several years. Her vital signs are pulse 90/min, blood pressure 120/67 mm Hg, respiratory rate 14/min, and temperature of 36.7°C (98.0°F). Her current BMI is 26 kg/m2. Her teeth are yellow-stained, but the physical examination is otherwise unremarkable. What is the next best step in her management?", "answer": "Start metoclopramide.", "options": {"A": "Prescribe a nicotine patch.", "B": "Abdominal radiographs", "C": "Start metoclopramide.", "D": "Endoscopic evaluation", "E": "Refer for bariatric surgery."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old girl presents to the emergency department with a severe headache. The patient has had headaches in the past, but she describes this as the worst headache of her life. Her symptoms started yesterday and have been getting progressively worse. The patient states that the pain is mostly on one side of her head. There has been a recent outbreak of measles at the patient’s school, and the patient’s mother has been trying to give her daughter medicine to prevent her from getting sick, but the mother fears that her daughter may have caught the measles. On physical exam, you note an obese young girl who is clutching her head with the light in the room turned off. Her neurological exam is within normal limits. Fundoscopic exam reveals mild bilateral papilledema. A MRI of the head is obtained and reveals cerebral edema. A lumbar puncture reveals an increased opening pressure with a normal glucose level. Which of the following is the most likely diagnosis?", "answer": "Fat-soluble vitamin overuse", "options": {"A": "Viral meningitis", "B": "Bacterial meningitis", "C": "Subarachnoid hemorrhage", "D": "Migraine headache", "E": "Fat-soluble vitamin overuse"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A previously healthy 1-year-old boy is brought to the emergency department because of irritability and fever for 2 days. His symptoms began shortly after returning from a family trip to Canada. He was born at term. His immunizations are up-to-date. His 6-year-old brother is healthy and there is no family history of serious illness. The boy appears weak and lethargic. He is at the 50th percentile for height and 75th percentile for weight. His temperature is 39.2°C (102.5°F), pulse is 110/min, respirations are 28/min, and blood pressure is 92/55 mm Hg. Physical examination shows several purple spots over the trunk and extremities that are 1 mm in diameter. Capillary refill time is 4 seconds. The remainder of the examination shows no abnormalities. His hemoglobin concentration is 12 g/dL, leukocyte count is 19,000/mm3, and platelet count is 225,000/mm3. A lumbar puncture is done; cerebrospinal fluid (CSF) analysis shows abundant segmented neutrophils, decreased glucose concentration, and an increased protein concentration. Which of the following is the most appropriate next step in management?", "answer": "Ceftriaxone and vancomycin therapy for the patient and rifampin prophylaxis for close contacts", "options": {"A": "Ampicillin therapy for the patient and ciprofloxacin prophylaxis for close contacts", "B": "Cefotaxime and vancomycin therapy for the patient and doxycycline prophylaxis for close contacts", "C": "Vancomycin therapy for the patient and rifampin prophylaxis for close contacts", "D": "Ceftriaxone and vancomycin therapy for the patient and rifampin prophylaxis for close contacts", "E": "Cefotaxime and vancomycin therapy for the patient and no prophylaxis for close contacts\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old woman is brought to the emergency room at a nearby hospital after being involved in a roadside accident in which she sustained severe chest trauma. Enroute to the hospital, morphine is administered for pain control. Upon arrival, the patient rapidly develops respiratory failure and requires intubation and mechanical ventilation. She is administered pancuronium in preparation for intubation but suddenly develops severe bronchospasm and wheezing. Her blood pressure also quickly falls from 120/80 mm Hg to 100/60 mm Hg. Which of the following best explains the most likely etiology of this complication?", "answer": "Histamine release", "options": {"A": "Autonomic stimulation", "B": "Drug interaction", "C": "Histamine release", "D": "Skeletal muscle paralysis", "E": "Underlying neuromuscular disease"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is studying intracellular processes in muscle tissue after denervation. A biopsy specimen is obtained from the biceps femoris muscle of an 82-year-old woman who sustained sciatic nerve injury. Investigation of the tissue specimen shows shrunken cells with dense eosinophilic cytoplasm, nuclear shrinkage, and plasma membrane blebbing. Which of the following best explains the muscle biopsy findings?", "answer": "Release of mitochondrial cytochrome c", "options": {"A": "Release of mitochondrial cytochrome c", "B": "Degradation of Bcl-2-associated X protein", "C": "Denaturation of cytoplasmic proteins", "D": "Deactivation of caspases", "E": "Inhibition of Fas/FasL interaction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 15-year-old girl is brought to the physician by her mother because of lower abdominal pain for the past 5 days. The pain is constant and she describes it as 7 out of 10 in intensity. Over the past 7 months, she has had multiple similar episodes of abdominal pain, each lasting for 4–5 days. She has not yet attained menarche. Examination shows suprapubic tenderness to palpation. Pubic hair and breast development are Tanner stage 4. Examination of the external genitalia shows no abnormalities. Pelvic examination shows bulging, bluish vaginal tissue. Rectal examination shows an anterior tender mass. Which of the following is the most effective intervention for this patient's condition?", "answer": "Perform hymenotomy", "options": {"A": "Administer oral contraceptives pills", "B": "Perform vaginal dilation", "C": "Administer ibuprofen", "D": "Perform hymenotomy", "E": "Administer gonadotropin-releasing hormone agonist therapy\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 46-year-old woman comes to the physician for a cognitive evaluation. She is an office manager. She has had increasing difficulties with multitasking and reports that her job performance has declined over the past 1 year. On mental status examination, short-term memory is impaired and long-term memory is intact. Laboratory studies, including thyroid-stimulating hormone and vitamin B12, are within the reference range. An MRI of the brain shows generalized atrophy, most pronounced in the bilateral medial temporal lobes and hippocampi. If this patient's condition has a genetic etiology, which of the following alterations is most likely to be found on genetic testing?", "answer": "Mutation in presenilin 1", "options": {"A": "Noncoding hexanucleotide repeats", "B": "Deletion of chromosome 21q", "C": "Mutation in presenilin 1", "D": "Expansion of CAG trinucleotide repeat", "E": "Presence of ApoE ε4 allele"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator, studying learning in primates, gives an experimental chimpanzee a series of puzzles to solve. The chimpanzee solves the puzzle when he is able to place a set of wooden blocks sequentially inside the next biggest block. When a puzzle is solved successfully, a 30-second audio clip of a pop song plays. 15 seconds after that, a tangerine drops into the chimpanzee's room. After 2 days of this regimen, the chimpanzee undergoes functional magnetic resonance imaging (fMRI) of his brain while hearing the audio clip, which shows markedly elevated neurotransmission in the ventral tegmental area and substantia nigra. Which of the following best explains the finding on fMRI?", "answer": "Classical conditioning", "options": {"A": "Positive reinforcement", "B": "Negative reinforcement", "C": "Displacement", "D": "Classical conditioning", "E": "Extinction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-year-old male adolescent presents to the pediatrician with his parents complaining that he is shorter than his peers. His past medical history does not suggest any specific recurrent or chronic disease. There is no history of weight gain, weight loss, constipation, dry skin, headache. Both his parents are of normal height. On physical examination, he is a well-fed, well-developed male and his vital signs are within normal range. His physical examination is completely normal. His sexual development corresponds to Tanner stage 2. Analysis of his growth charts suggests that his height and weight at birth were within normal range. After the age of six months, his height and weight curves drifted further from average and approached the 5th percentile. An X-ray of the patient’s left hand reveals delayed bone age. Which of the following is the most likely cause of short stature in the boy?", "answer": "Constitutional growth delay", "options": {"A": "Constitutional growth delay", "B": "Familial short stature", "C": "Congenital adrenal hyperplasia", "D": "Growth hormone deficiency", "E": "Hypothyroidism"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 53-year-old female visits her physician with watery diarrhea and episodic flushing. The patient reports that she is often short of breath, and a pulmonary exam reveals bilateral wheezing. A CT scan shows a mass in the terminal ileum. 24-hour urine collection shows abnormally elevated 5-hydroxyindoleacetic acid (HIAA) levels. Ultrasound demonstrates a tricuspid valve with signs of fibrosis with a normal mitral valve. A metastatic disease to which organ is most commonly associated with the patient's syndrome?", "answer": "Liver", "options": {"A": "Lung", "B": "Kidney", "C": "Brain", "D": "Liver", "E": "Pancreas"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A patient weighing 70 kg (154 lb) requires intravenous antibiotics for a calcified abscess. The desired target plasma concentration of the antibiotic is 4.5 mg/L. The patient is estimated to have a volume of distribution of 30 L and a clearance rate of 60 mL/min. How many milligrams of the drug should be administered for the initial dose to reach the desired target plasma concentration?", "answer": "135 mg", "options": {"A": "135 mg", "B": "270 mg", "C": "35 mg", "D": "200 mg", "E": "70 mg"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 82-year-old man with alcohol use disorder is brought to the emergency department from his assisted living facility because of fever and cough for 1 week. The cough is productive of thick, mucoid, blood-tinged sputum. His temperature is 38.5°C (101.3°F) and respirations are 20/min. Physical examination shows coarse inspiratory crackles over the right lung field. Sputum cultures grow gram-negative, encapsulated bacilli that are resistant to amoxicillin, ceftriaxone, and aztreonam. Which of the following infection control measures is most appropriate for preventing transmission of this organism to other patients in the hospital?", "answer": "Isolate patient to a single-occupancy room", "options": {"A": "Require all staff and visitors to wear droplet masks", "B": "Transfer patient to a positive pressure room", "C": "Require autoclave sterilization of all medical instruments", "D": "Isolate patient to a single-occupancy room", "E": "Transfer patient to a negative pressure room"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old boy presents to the Emergency Department with wheezing and shortness of breath after playing with the new family pet. Which of the following immunological factors is most involved in generating the antibodies necessary for mast cell Fc-receptor cross-linking and degranulation?", "answer": "IL-4", "options": {"A": "IL-2", "B": "IL-4", "C": "IL-5", "D": "IL-10", "E": "IL-13"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old man is brought to his psychiatrist by his wife. The patient’s wife says his last visit was 3 years ago for an episode of depression. At that time, he was prescribed fluoxetine, which he did not take because he believed that his symptoms would subside on their own. A few months later, his wife says that he suddenly came out of his feelings of ‘depression’ and began to be more excitable and show pressured speech. She observed that he slept very little but had a heightened interest in sexual activity. This lasted for a few weeks, and he went back to his depressed state. He has continued to experience feelings of sadness and shows a lack of concentration at work. She often finds him crying, and he also expresses feelings of guilt for all the wrongs he allegedly did to her and to the family. There was a week where he had a brief time of excitability and was considering donating all their savings to a local charity. She is highly perturbed by his behavior and often finds it hard to predict what his mood will be like next. The patient denies any suicidal or homicidal ideations. A urine toxicology screen is negative. All laboratory tests, including thyroid hormone levels, are normal. Which of the following is the most appropriate diagnosis in this patient?", "answer": "Cyclothymia", "options": {"A": "Major depressive disorder", "B": "Dysthymia", "C": "Cyclothymia", "D": "Bipolar disorder, type I", "E": "Schizoaffective disorder"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A previously healthy 56-year-old woman comes to the family physician for a 1-month history of sleep disturbance and sadness. The symptoms have been occurring since her husband died in a car accident. Before eventually falling asleep, she stays awake for multiple hours and has crying spells. Several times she has been woken up by the sound of her husband calling her name. She has lost 3 kg (6.6 lb) over the past month. She has 3 children with whom she still keeps regular contact and regularly attends church services with her friends. She expresses feeling a great feeling of loss over the death of her husband. She has no suicidal ideation. She is alert and oriented. Neurological exam shows no abnormalities. Which of the following is the most likely diagnosis for this patient's symptoms?", "answer": "Normal bereavement", "options": {"A": "Schizoaffective disorder", "B": "Normal bereavement", "C": "Acute stress disorder", "D": "Major depressive disorder", "E": "Adjustment disorder with depressed mood"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 75-year-old man comes to the physician because of a 2-month history of intermittent bright red blood in his stool, progressive fatigue, and a 5-kg (11-lb) weight loss. He appears thin and fatigued. Physical examination shows conjunctival pallor. Hemoglobin concentration is 7.5 g/dL and MCV is 77 μm3. Results of fecal occult blood testing are positive. A colonoscopy shows a large, friable mass in the anal canal proximal to the pectinate line. Primary metastasis to which of the following lymph nodes is most likely in this patient?", "answer": "Internal iliac", "options": {"A": "Inferior mesenteric", "B": "Internal iliac", "C": "External iliac", "D": "Para-aortic", "E": "Deep inguinal"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old woman presents with weight gain and marks on her abdomen (as seen in the image below). She does not have any significant past medical history. She is a nonsmoker and denies any alcohol use. Her blood pressure is 160/110 mm Hg and pulse is 77/min. A T1/T2 MRI of the head shows evidence of a pituitary adenoma, and she undergoes surgical resection of the tumor. Which of the following therapies is indicated in this patient to ensure normal functioning of her hypothalamic-pituitary-adrenal (HPA) axis?", "answer": "Hydrocortisone", "options": {"A": "Bilateral adrenalectomy", "B": "Fludrocortisone", "C": "Hydrocortisone", "D": "Mometasone", "E": "Methotrexate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old man presents with a sudden-onset severe headache and vomiting for the past 2 hours. Past medical history is significant for poorly controlled hypertension, managed with multiple medications. His blood pressure is 188/87 mm Hg and pulse is 110/min. A non-contrast CT of the head is unremarkable and cerebrospinal fluid analysis is within normal limits, except for an RBC count of 5.58 x 106/mm3. Labetalol IV is administered. Which of the following medications should also be added to this patient’s management?", "answer": "Nimodipine", "options": {"A": "Nifedipine", "B": "Verapamil", "C": "Furosemide", "D": "Nimodipine", "E": "Ecosprin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old patient comes to the physician with complaints of dysuria and white urethral discharge. He is sexually active with 4 partners and does not use condoms. The physician is concerned for a sexually transmitted infection and decides to analyze the nucleic acid sequences present in the discharge to aid in diagnosis via DNA amplification. Which of the following is responsible for the creation of the nucleic acid copies during the elongation phase of the technique most likely used in this case?", "answer": "Heat-resistant DNA polymerase", "options": {"A": "DNA primers", "B": "Nucleotide sequence of the target gene", "C": "Amino acid sequence of the target gene", "D": "Heat-sensitive DNA polymerase", "E": "Heat-resistant DNA polymerase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 61-year-old man is brought to the emergency department by his wife because of increasing confusion over the past 12 hours. His wife reports that he has a history of type 1 diabetes mellitus. His temperature is 38.8°C (101.8°F). He is confused and oriented only to person. Examination shows left periorbital swelling that is tender to palpation, mucopurulent rhinorrhea, and a black necrotic spot over the nose. There is discharge of the left eye with associated proptosis. A photomicrograph of a specimen obtained on biopsy of the left maxillary sinus is shown. Which of the following is the most likely causal organism?", "answer": "Rhizopus microsporus", "options": {"A": "Pseudomonas aeruginosa", "B": "Rhizopus microsporus", "C": "Aspergillus fumigatus", "D": "Blastomyces dermatitidis", "E": "Pneumocystis jirovecii"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 57-year-old woman comes to the physician because of a 6-month history of tinnitus and progressive hearing loss in the left ear. She has type 2 diabetes mellitus and Raynaud syndrome. Her current medications include metformin, nifedipine, and a multivitamin. She appears well. Vital signs are within normal limits. Physical examination shows no abnormalities. A vibrating tuning fork is placed on the left mastoid process. Immediately after the patient does not hear a tone, the tuning fork is held over the left ear and she reports hearing the tuning fork again. The same test is repeated on the right side and shows the same pattern. The vibration tuning fork is then placed on the middle of the forehead and the patient hears the sound louder in the right ear. Which of the following is the most likely diagnosis?", "answer": "Acoustic neuroma", "options": {"A": "Meningioma", "B": "Presbycusis", "C": "Acoustic neuroma", "D": "Cerumen impaction", "E": "Ménière disease\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-week-old boy is brought to the emergency department with a 2-day history of projectile vomiting after feeding. His parents state that he is their firstborn child and that he was born healthy. He developed normally for several weeks but started to eat less 1 week ago. Physical exam reveals a small, round mass in the right upper quadrant of the abdomen close to the midline. The infant throws up in the emergency department, and the vomitus is observed to be watery with no traces of bile. Which of the following is associated with the most likely cause of this patient's symptoms?", "answer": "Nitric oxide synthase deficiency", "options": {"A": "Chloride transport defect", "B": "Failure of neural crest migration", "C": "Nitric oxide synthase deficiency", "D": "Recanalization defect", "E": "Vascular accident"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 49-year-old woman is brought in to the emergency department by ambulance after developing crushing chest pain and palpitations. Past medical history is significant for hypertension, hyperlipidemia, and obesity. She takes chlorthalidone, lisinopril, atorvastatin, metformin, and an oral contraceptive every day. She works as a lawyer and her job is stressful. She drinks wine with dinner every night and smokes 10 cigarettes a day. Emergency personnel stabilized her and administered oxygen while on the way to the hospital. Upon arrival, the vital signs include: blood pressure 120/80 mm Hg, heart rate 120/min, respiratory rate 22/min, and temperature 37.7°C (99.9°F). On physical exam, she is an obese woman in acute distress. She is diaphoretic and has difficulty catching her breath. A bedside electrocardiogram (ECG) is performed which reveals ST-segment elevation in leads II, III, and aVF. Which of the following is the most probable diagnosis?", "answer": "Inferior wall myocardial infarction ", "options": {"A": "Inferior wall myocardial infarction ", "B": "Lateral wall myocardial infarction", "C": "Posterior wall myocardial infarction", "D": "Anteroseptal myocardial infarction", "E": "Right ventricular myocardial infarction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old woman presents for an evaluation for snoring. According to her husband, her snoring has increased over the last year, and he can’t tolerate it anymore. He has also noticed that she wakes up at night regularly for a few seconds but then falls back asleep. During the day, the patient says she is sleepy most of the time and complains of headaches and poor concentration. Past medical history is significant for hypertension and hyperlipidemia. Her temperature is 36.6°C (97.9°F), blood pressure is 156/98 mm Hg, pulse is 90/min and respirations are 20/min. Her body mass index (BMI) is 38 kg/m2. A polysomnographic study is ordered, and the result is shown below. While counseling the patient about her condition and available treatment options, she is asked if she wants to try a new therapy in which a device stimulates one of her cranial nerves. Which of the following muscles would most likely be stimulated by this method?", "answer": "Genioglossus muscle", "options": {"A": "Genioglossus muscle", "B": "Digastric muscle", "C": "Hyoglossus muscle", "D": "Palatoglossus muscle", "E": "Intercostal muscles"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-week-old male infant is brought to the physician because of a 1-week history of refusing to finish all his bottle feeds and becoming irritable shortly after feeding. He has also spit up sour-smelling milk after most feeds. Pregnancy and delivery were uncomplicated, with the exception of a positive vaginal swab for group B streptococci 6 weeks ago, for which the mother received one dose of intravenous penicillin. The baby is at the 70th percentile for length and 50th percentile for weight. His temperature is 36.6°C (98°F), pulse is 180/min, respirations are 30/min, and blood pressure is 85/55 mm Hg. He appears lethargic. Examination shows sunken fontanelles and a strong rooting reflex. The abdomen is soft with a 1.5-cm (0.6-inch) nontender epigastric mass. Examination of the genitals shows a normally pigmented scrotum, retractile testicles that can be pulled into the scrotum, a normal-appearing penis, and a patent anus. Which of the following interventions would have been most likely to decrease the patient's risk of developing his condition?", "answer": "Breastfeeding only", "options": {"A": "Feeding of soy milk formula", "B": "Breastfeeding only", "C": "Avoiding penicillin administration to the mother", "D": "Treating the infant with glucocorticoids", "E": "Performing cesarean section\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old woman status-post liver transplant presents to her transplant surgeon because she has noticed increased urination over the last 3 weeks. Six months ago she received a liver transplant because of fulminant liver failure after viral hepatitis. Since then, she has noticed that she has been drinking more water and urinating more. Her husband has also noticed that she has been eating a lot more. She says that she never had these symptoms prior to her transplant and has been taking her medications on time. After confirmatory tests, she is started on a medication that binds to an ATP-gated potassium channel. The drug that increases the risk of the complication experienced by this patient most likely has which of the following mechanisms of action?", "answer": "Binding to FKBP-12 to inhibit calcineurin", "options": {"A": "Binding to cyclophilin D to inhibit calcineurin", "B": "Binding to FKBP-12 to inhibit calcineurin", "C": "Inosine monophosphate dehydrogenase inhibitor", "D": "Conversion into 6-mecaptopurine", "E": "Targeting the a-chain of the IL-2 receptor"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old woman with a history of recent gastric bypass surgery presents for a follow-up visit. 8 months ago, she underwent gastric bypass surgery because she was struggling with maintaining her BMI below 42 kg/m². She previously weighed 120 kg (265 lb), and now she weighs 74.8 kg (165 lb). She says that she has low energy and is easily fatigued. These symptoms have become progressively worse over the past month. She is struggling to get through the day and sometimes has to nap before she can continue with her work. She has also recently noticed that she gets cramps in her legs, especially after a long day. The patient is afebrile and vital signs are within normal limits. Physical examination is unremarkable. Her hemoglobin is 9.5 mg/dL with an MCV of 75 fl. Her peripheral smear is shown in the exhibit. Which of the following supplements would most likely improve this patient’s symptoms?", "answer": "Iron", "options": {"A": "Calcium", "B": "Pyridoxine", "C": "Retinoids", "D": "Methylcobalamin", "E": "Iron"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 19-year-old woman comes to the physician for a routine health maintenance examination. She appears well. Her vital signs are within normal limits. Cardiac auscultation shows a mid-systolic click and a grade 3/6, late-systolic, crescendo murmur that is best heard at the cardiac apex in the left lateral recumbent position. After the patient stands up suddenly, the click is heard during early systole and the intensity of the murmur increases. Which of the following is the most likely underlying cause of this patient's examination findings?", "answer": "Dermatan sulfate deposition", "options": {"A": "Myosin heavy chain defect", "B": "Dermatan sulfate deposition", "C": "Congenital valvular fusion", "D": "Congenital interventricular communication", "E": "Dystrophic valvular calcification\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old woman with ovarian cancer comes to the physician with a 5-day history of fever, chills, and dyspnea. She has a right subclavian chemoport in which she last received chemotherapy 2 weeks ago. Her temperature is 39.5°C (103.1°F), blood pressure is 110/80 mm Hg, and pulse is 115/min. Cardiopulmonary examination shows jugular venous distention and a new, soft holosystolic murmur heard best in the left parasternal region. Crackles are heard at both lung bases. Echocardiography shows a vegetation on the tricuspid valve. Peripheral blood cultures taken from this patient is most likely to show which of the following findings?", "answer": "Gram-positive, catalase-positive, coagulase-positive cocci in clusters", "options": {"A": "Gram-positive, catalase-negative, α-hemolytic, optochin-resistant cocci in chains", "B": "Gram-positive, catalase-positive, coagulase-negative, novobiocin-resistant cocci in clusters", "C": "Gram-positive, catalase-positive, coagulase-positive cocci in clusters", "D": "Gram-positive, catalase-negative, nonhemolytic, salt-sensitive cocci in chains", "E": "Gram-positive, catalase-negative, β-hemolytic, bacitracin-resistant cocci in chains"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman at 28 weeks gestation seeks evaluation at her obstetrician’s office with complaints of a severe headache, blurred vision, and vomiting for the past 2 days. Her pregnancy has been otherwise uneventful. The past medical history is unremarkable. The blood pressure is 195/150 mm Hg and the pulse is 88/min. On examination, moderate pitting edema is present in her ankles. The urinalysis is normal except for 3+ proteinuria. The obstetrician orders a complete blood count (CBC), liver function tests (LFTs), creatinine, and a coagulation profile. The obstetrician transfers her to the hospital by ambulance for expectant management. Which of the following medications would be most helpful for this patient?", "answer": "Nifedipine", "options": {"A": "Hydrochlorothiazide", "B": "Lisinopril", "C": "Metoprolol", "D": "Olmesartan", "E": "Nifedipine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old G0P0000 presents to her gynecologist with complaints of irregular menstruation. She has had only two periods in the last year. She also endorses feeling flushed without provocation and experiencing occasional dyspareunia with post-coital spotting. In addition, she has also had more frequent headaches than usual. The patient has a past medical history of Hashimoto’s thyroiditis and takes levothyroxine daily. Her mother has type I diabetes mellitus. At this visit, the patient’s temperature is 98.5°F (36.9°C), pulse is 70/min, blood pressure is 118/76 mmHg, and respirations are 13/min. Cardiopulmonary and abdominal exams are unremarkable. The patient has Tanner V breasts and pubic hair. Pelvic exam reveals a normal cervix, anteverted uterus without tenderness, and no adnexal masses. The following laboratory studies are performed:\n\nSerum:\nThyroid stimulating hormone (TSH): 28 µIU/mL (9-30 µIU/mL)\nCycle day 3 follicle stimulating hormone (FSH): 49 mIU/mL (4.7-21.5 mIU/mL)\nCycle day 3 estradiol: 8 pg/mL (27-123 pg/mL)\nProlactin: 14 ng/mL (4-23 ng/mL)\nTestosterone: 42 ng/dL (15-70 ng/dL)\n\nWhich of the following is the best next step in management?", "answer": "Estradiol patch with oral medroxyprogesterone", "options": {"A": "Vaginal estradiol gel", "B": "Increase levothyroxine dose", "C": "Estradiol patch with oral medroxyprogesterone", "D": "Brain MRI", "E": "Combined oral contraceptive"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old man comes to the clinic complaining of yellow skin and eyes, loss of appetite, and severe nausea over the last month or so. He drinks 2–3 beers everyday and about 5–6 on the weekend. He does not take any over-the-counter medications. He has smoked one pack of cigarettes every day for the last 20 years but does not use illicit drugs. Additionally, he reports no history of vomiting, abdominal pain, altered bowel habits, or unintentional weight loss. His temperature is 37°C (98.6°F), blood pressure is 135/85 mm Hg, pulse is 78/ min, respiratory rate is 14/ min, and BMI is 19 kg/m2. On physical examination his skin and sclera are icteric, and his abdomen is tender with a mildly enlarged liver. On laboratory investigations:\nComplete blood count\nHemoglobin 11 g/dL\nMCV 105 µm3\nWhite blood cell 14,000/mm3\nPlatelets 110,000/mm3\nWhich of the following liver function analyses is expected in this patient?", "answer": "Alanine aminotransferase (ALT): 120 / Aspartate aminotransferase (AST): 256 / AST/ALT: 2.1", "options": {"A": "Alanine aminotransferase (ALT): 38/ Aspartate aminotransferase (AST): 30 / AST/ALT: 0.79", "B": "Alanine aminotransferase (ALT): 1,500 / Aspartate aminotransferase (AST): 1,089 / AST/ALT: 0.73", "C": "Alanine aminotransferase (ALT): 120 / Aspartate aminotransferase (AST): 256 / AST/ALT: 2.1", "D": "Alanine aminotransferase (ALT): 83 / Aspartate aminotransferase (AST): 72 / AST/ALT: 0.87", "E": "Alanine aminotransferase (ALT): 2,521 / Aspartate aminotransferase (AST): 2,222 / AST/ALT: 0.88"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old man comes to the physician because of 2 episodes of bleeding from the rectum over the past month. The patient’s father died of colon cancer at the age of 42. The patient has no history of any serious illness and takes no medications. He does not smoke. His vital signs are within normal limits. Physical examination shows a small hard mass over the right mandible that is nontender and fixed to the underlying bone. A similarly hard and painless 5 × 5 mass is palpated over the rectus abdominis muscle. On examination of the rectum, a polypoid mass is palpated at fingertip. Proctosigmoidoscopy shows numerous polyps. Which of the following best explains these findings?", "answer": "Gardner’s syndrome", "options": {"A": "Familial polyposis of the colon", "B": "Gardner’s syndrome", "C": "Lynch’s syndrome", "D": "Peutz-Jeghers syndrome", "E": "Turcot’s syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 56-year-old man is brought to the emergency department after falling 16 feet from a ladder. He has severe pain in both his legs and his right arm. He appears pale and diaphoretic. His temperature is 37.5°C (99.5°F), pulse is 120/min and weak, respirations are 26/min, and blood pressure is 80/50 mm Hg. He opens his eyes and withdraws in response to painful stimuli and makes incomprehensible sounds. The abdomen is soft and nontender. All extremities are cold, with 1+ pulses distally. Arterial blood gas analysis on room air shows:\npH 7.29\nPCO2 33 mm Hg\nPO2 65 mm Hg\nHCO3- 15 mEq/L\nA CT scan shows displaced fractures of the pelvic ring, as well as fractures of both tibiae, the right distal radius, and right proximal humerus. The patient undergoes emergent open reduction and is admitted to the intensive care unit. Which of the following best indicates inadequate fluid resuscitation?\"", "answer": "Urine output of 25 mL in 3 hours", "options": {"A": "High pulse pressure", "B": "Urine output of 25 mL in 3 hours", "C": "Glasgow coma score of 8", "D": "Capillary refill time of 3 seconds", "E": "Base deficit of 1 mmol/L\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the pediatrician for recurrent nosebleeds. The boy was adopted two months ago and the parents have no record of his medical or family history. They report that the child has had frequent prolonged nosebleeds several times per week. Despite them applying pressure on the distal aspect of the nares and keeping his head elevated, the bleeding generally continues for hours. On exam, the boy appears pale and lethargic. A blood sample is obtained but the child bleeds through multiple pieces of gauze. No agglutination is observed when ristocetin is added to the patient’s blood. The addition of normal plasma to the sample still does not lead to agglutination. This patient has a condition that is most consistent with which of the following modes of transmission?", "answer": "Autosomal recessive", "options": {"A": "Autosomal dominant", "B": "Autosomal recessive", "C": "Mitochondrial", "D": "X-linked dominant", "E": "X-linked recessive"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old man comes to the physician with his son for a follow-up examination. The son reports that his father's mental status has declined since the previous visit when he was diagnosed with Alzheimer dementia. The patient often begins tasks and forgets what he was doing. He has increased trouble remembering events that occurred the day before and sometimes forgets names of common household objects. He has hypertension and hyperlipidemia. His current medications include lisinopril, hydrochlorothiazide, atorvastatin, and donepezil. He is confused and oriented only to person. He is unable to count serial sevens backward from 100. He is able to register 3 items but unable to recall them 5 minutes later. Which of the following is the most appropriate pharmacotherapy?", "answer": "Memantine", "options": {"A": "Risperidone", "B": "Ginkgo biloba", "C": "Citalopram", "D": "Memantine", "E": "Vitamin E"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old female presents to her gynecologist complaining of vaginal discomfort. She reports that over the past two weeks, she has developed dyspareunia and feels as if there is a mass on the external aspect of her vagina. She is sexually active in a monogamous relationship. On physical examination, there is a 2 cm unilateral erythematous swelling on the right side of the posterolateral labia minora. Which of the following embryologic precursors gives rise to the affected tissue in this patient?", "answer": "Urogenital sinus", "options": {"A": "Paramesonephric duct", "B": "Genital tubercle", "C": "Urogenital sinus", "D": "Urogenital fold", "E": "Labioscrotal swelling"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 34-year-old woman comes to the emergency department complaining of severe headache and anxiety, diaphoresis, and palpitations for the last 30 minutes. She has had several similar episodes over the past few weeks. She has no significant past medical history and has a 10 pack-year smoking history. She takes no illicit drugs. Her blood pressure on arrival is 181/80 mmHg and her pulse is 134/min. If this patient was given metoprolol, how would her blood pressure respond?", "answer": "Hypertension due to alpha-1-adrenergic receptor stimulation", "options": {"A": "Hypotension due to beta-adrenergic receptor blockade", "B": "Hypotension due to alpha-1-adrenergic receptor blockade", "C": "Hypertension due to alpha-1-adrenergic receptor blockade", "D": "Hypertension due to alpha-1-adrenergic receptor stimulation", "E": "Hypertension due to alpha- and beta-adrenergic receptor blockade"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old woman comes to the physician with a 2-week history of new pruritic plaques on the scalp and extensor surfaces of the elbows and knees. Ten years ago, she was diagnosed with psoriasis. Her only medication is topical calcipotriene. Physical examination shows well-demarcated, symmetrical, erythematous plaques with silvery scale. There is pitting of the nails on all fingers. Therapy with a high-potency topical medication that inhibits NF-κB and phospholipase A2 is begun. Long-term use of this agent is most likely to result in which of the following?", "answer": "Dermal collagen loss", "options": {"A": "Dysplastic nevi", "B": "Nonblanchable pinpoint macules", "C": "Decreased sebum production", "D": "Dermal collagen loss", "E": "Hair growth on upper lip"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman is brought to a psychiatrist’s office by her husband who states that he is worried about her recent behavior, as it has become more violent. The patient’s husband states that his family drove across the country to visit them and that his wife ‘threatened his parents with a knife’ at dinner last night. Police had to be called to calm her down. He states that she has been acting ‘really crazy’ for the last 9 months, and the initial behavior that caused him alarm was her admission that his deceased sister was talking to her through a decorative piece of ceramic art in the living room. Initially, he thought she was joking, but soon realized her complaints of ‘hearing ghosts’ talking to her throughout the house were persisting and ‘getting worse’. There was also a 4-week period where she experienced insomnia and an unintentional weight loss of 12 pounds. She seemed sad throughout these episodes, and, according to her husband, was complaining of feeling ‘worthless’. Her general hygiene has also suffered from her recent lack of motivation and she insists that the ‘ghosts’ are asking her to kill as many people as she can so they won’t be alone in the house. Her husband is extremely concerned that she may harm herself or someone else. He states that she currently does not take any medications or illicit drugs as far as he knows. She does not smoke or drink alcohol. The patient herself does not make eye contact or want to speak to the psychiatrist, allowing her husband to speak on her behalf. Which of the following is the most likely diagnosis in this patient?", "answer": "Schizoaffective disorder", "options": {"A": "Schizoaffective disorder", "B": "Brief psychotic disorder", "C": "Schizophreniform disorder", "D": "Schizophrenia", "E": "Delusional disorder"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old previously healthy man presents to the clinic complaining of bloody diarrhea and abdominal pain. Sexual history reveals that he has sex with men and women and uses protection most of the time. He is febrile with all other vital signs within normal limits. Physical exam demonstrates tenderness to palpation of the right upper quadrant. Subsequent ultrasound shows a uniform cyst in the liver. In addition to draining the potential abscess and sending it for culture, appropriate medical therapy would involve which of the following?", "answer": "Metronidazole and iodoquinol", "options": {"A": "Amphotericin", "B": "Nifurtimox", "C": "Supportive therapy", "D": "Sulfadiazine and pyrimethamine", "E": "Metronidazole and iodoquinol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 81-year-old man is brought to the physician by his daughter after being found wandering on the street. His daughter says that over the past several months he has been more aggressive towards friends and family. She also reports several episodes in which he claimed to see two strangers in her apartment. He sometimes stares blankly for several minutes and does not react when addressed. He has hypertension, hyperlipidemia, and was diagnosed with Parkinson disease 10 months ago. His current medications include carbidopa-levodopa, hydrochlorothiazide, and atorvastatin. His temperature is 37°C (98.6°F), pulse is 99/min, and blood pressure is 150/85 mm Hg. He is confused and oriented to person and place but not to time. There is a resting tremor in his right upper extremities. There is muscle rigidity in the upper and lower extremities. He is able to walk without assistance but has a slow gait with short steps. Mental status examination shows short-term memory deficits. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Lewy body deposition", "options": {"A": "Lewy body deposition", "B": "Vascular infarcts", "C": "Frontotemporal lobe atrophy", "D": "Thiamine deficiency", "E": "Impaired CSF absorption"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old woman comes to the physician because of fever, chills, headache, and nausea over the past 3 days. Nine months ago, she returned from a vacation in Indonesia where she had experienced similar symptoms and episodic fever. She was treated with chloroquine and recovered uneventfully. Her temperature is 39.1°C (102.4°F), pulse is 97/min, and blood pressure is 123/85 mm Hg. Physical examination shows scleral icterus. The abdomen is soft; bowel sounds are active. Neurologic examination is unremarkable. Her hemoglobin concentration is 10 g/dL. A photomicrograph of a peripheral blood smear is shown. Which of the following is the most likely cause of the recurrence of symptoms in this patient?", "answer": "Reactivation of dormant liver stage", "options": {"A": "Decline in circulating antibodies", "B": "Reinfection by Anopheles mosquito", "C": "Natural drug resistance", "D": "Reactivation of dormant liver stage", "E": "Dissemination within macrophages"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 6-month-old child is brought to the pediatrician by his parents for difficulty feeding and poor motor function. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones until 2 months ago. He started having trouble latching onto his bottle. He has also become extremely lethargic. Examination reveals diminished muscle tone in all four limbs, areflexia, and hepatosplenomegaly. A ophthalmoscopic exam reveals macular cherry red spots. Which of the following is most likely deficient in this child?", "answer": "Sphingomyelinase", "options": {"A": "ß-Glucosidase", "B": "Hexosaminidase A", "C": "Arylsulfatase A", "D": "Ceramidase", "E": "Sphingomyelinase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old G1P0 woman, at 12 weeks estimated gestational age, presents for her first prenatal visit. Past medical history reveals the patient has type O+ blood and that her husband has type A+ blood. The patient is worried about the risk of her baby having hemolytic disease. Which of the following is correct regarding fetomaternal incompatibility in this patient?", "answer": "It is a rare cause of newborn hemolytic disease", "options": {"A": "It cannot affect first borns", "B": "It is more severe than RhO (D) alloimmunization", "C": "Prenatal detection is very important because fetomaternal incompatibility is associated with severe fetal anemia", "D": "A direct Coombs test is strongly positive", "E": "It is a rare cause of newborn hemolytic disease"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 80-year-old male is found dead at home and brought in for an autopsy. The patient's heart shows a diminished ventricular chamber volume and the interventricular septum appears sigmoid shaped. The left atrium appears enlarged as well. A few calcifications are seen on the undamaged aortic valves. Microscopic examination reveals increased connective tissue in the myocardium and brown perinuclear cytoplasmic granules in numerous myocardial cells as shown in the exhibit. Which of the following most likely explains this patient's cardiac findings?", "answer": "Expected age related changes", "options": {"A": "Chronic hemolytic anemia", "B": "Dilated cardiomyopathy", "C": "Expected age related changes", "D": "Hypertrophic cardiomyopathy", "E": "Uncontrolled hypertension"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 39-year-old man comes to the physician because of a 4-month history of fatigue. During this period, he has also had a 7.7-kg (17-lb) weight loss, despite having a normal appetite. He is sexually active with 3 female partners and uses condoms inconsistently. An HIV screening test and confirmatory test are both positive. CD4+ T-lymphocyte count is 570/mm3 (N ≥ 500) and the viral load is 104 copies/mL. Treatment with lamivudine, zidovudine, and indinavir is begun. The patient is most likely to experience which of the following adverse effects?", "answer": "Urolithiasis", "options": {"A": "Hyperpigmentation of palms and soles", "B": "Hepatotoxicity", "C": "Urolithiasis", "D": "Pancreatitis", "E": "Stevens-Johnson syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 49-year-old obese woman presents with a chronic non-healing ulcer on the right medial malleolus. Past medical history is significant for type 2 diabetes mellitus, diagnosed 10 years ago, poorly managed with metformin. Review of systems is significant for a recurrent white vaginal discharge. The patient is afebrile, and her vital signs are within normal limits. Her BMI is 31 kg/m2. On physical examination, there is a 2 cm by 2 cm nontender, erythematous shallow ulcer present over the right medial malleolus. Sensation is decreased symmetrically in the lower extremities below the level of the midcalf. Which of the following histopathological findings would most likely be seen in the peripheral nerves in this patient?", "answer": "Reduced axonal fiber diameter and fiber density", "options": {"A": "Wallerian degeneration", "B": "Reduced axonal fiber diameter and fiber density", "C": "Acute perivascular inflammation", "D": "Lymphocytic infiltration of the endoneurium", "E": "Accumulation of beta-pleated sheets of amyloid protein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old woman is brought to the emergency department by her daughter because of left-sided weakness for 1 hour. She does not have headache or blurring of vision. She has hypertension, hypercholesterolemia, type 2 diabetes, and coronary artery disease. She has smoked one half-pack of cigarettes daily for 45 years. Her medications include atorvastatin, amlodipine, metformin, and aspirin. Her temperature is 37°C (98.6°F), pulse is 92/min, and blood pressure is 168/90 mm Hg. Examination shows a left facial droop. Muscle strength is decreased on the left side. Deep tendon reflexes are 3+ on the left. Sensation to pinprick, light touch, and vibration as well as two-point discrimination are normal. Which of the following is the most likely cause of these findings?", "answer": "Lipohyalinosis of lenticulostriate arteries", "options": {"A": "Atherosclerosis of the internal carotid artery", "B": "Rupture of an intracranial aneurysm", "C": "Lipohyalinosis of lenticulostriate arteries", "D": "Dissection of the vertebral artery", "E": "Embolism from the left atrium"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old male is brought to the emergency room following a violent assault in which he was stabbed in the chest. The knife penetrated both the left lung and the left ventricle. Where did the knife most likely enter his chest?", "answer": "Left fifth intercostal space in the midclavicular line", "options": {"A": "Left seventh intercostal space in the midaxillary line", "B": "Left seventh intercostal space in the midclavicular line", "C": "Left fifth intercostal space just lateral to the sternum", "D": "Left fifth intercostal space in the midaxillary line", "E": "Left fifth intercostal space in the midclavicular line"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 69-year-old man is brought to the emergency department for severe tearing lower back pain for 12 hours. The pain radiates to the flank and he describes it as 8 out of 10 in intensity. He has nausea and has vomited several times. He has no fever, diarrhea, or urinary symptoms. When he stands up suddenly, he becomes light-headed and has to steady himself for approximately 1 to 2 minutes before he is able to walk. He has hypertension and hyperlipidemia. Two years ago, he had a myocardial infarction and underwent coronary artery bypass grafting of his right coronary artery. He has smoked one and a half packs of cigarettes daily for 40 years and drinks 1 to 2 beers daily. His current medications include chlorthalidone, atorvastatin, lisinopril, and aspirin. He appears acutely ill. His temperature is 37.2°C (98.9°F), pulse is 130/min and regular, respirations are 35/min, and blood pressure is 80/55 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 85%. Examination shows a pulsatile mass in the abdomen. Intravenous fluids and high-flow oxygen are started. Thirty minutes later, the patient dies. Which of the following was the strongest predisposing factor for the condition leading to this patient's death?", "answer": "Smoking", "options": {"A": "Advanced age", "B": "Hyperlipidemia", "C": "Male sex", "D": "Hypertension", "E": "Smoking"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 48-year-old African American male presents to his primary care provider complaining of facial swelling. He reports a three-day history of worsening swelling primarily around his eyes. The patient’s medical history is notable for sickle cell disease and poorly controlled hypertension. The patient currently takes enalapril, hydrochlorothiazide, and amlodipine but has a history of medication non-adherence. He has a 15 pack-year smoking history. His temperature is 99.1°F (37.3°C), blood pressure is 155/100 mmHg, pulse is 90/min, and respirations are 20/min. Physical examination is notable for periorbital swelling and 1+ bilateral lower extremity edema. Multiple serum and urine labs are ordered. A kidney biopsy in this patient would most likely yield which of the following sets of findings on light and electron microscopy?", "answer": "Segmental sclerosis and negative immunofluorescence and foot process effacement", "options": {"A": "Wire looping capillaries and subendothelial immune complex deposition", "B": "Hypercellular glomeruli with neutrophils and subepithelial immune complex deposition", "C": "Increased mesangial cellularity and mesangial immune complex deposition", "D": "Diffusely thickened capillaries and subepithelial immune complex deposition", "E": "Segmental sclerosis and negative immunofluorescence and foot process effacement"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old man comes to the physician because of a 9-month history of sleep disturbances, restlessness, and difficulty acquiring erections. He has difficulty falling asleep and wakes up at least 3 times per night. He worries about paying his bills, failing law school, and disappointing his parents. He can no longer concentrate in class and failed the last exam. He feels on edge most days and avoids socializing with his classmates. He worries that he has an underlying medical condition that is causing his symptoms. Previous diagnostic evaluations were unremarkable. There is no personal or family history of serious illness. He is sexually active with his girlfriend. He has a history of drinking alcohol excessively during his early 20s, but he has not consumed alcohol for the past 3 years. He appears anxious. Vital signs are within normal limits. On mental status examination, he is oriented to person, place, and time. Physical examination shows no abnormalities. In addition to psychotherapy, treatment with which of the following drugs is most appropriate in this patient?", "answer": "Buspirone", "options": {"A": "Buspirone", "B": "Doxepin", "C": "Propranolol", "D": "Lorazepam", "E": "Valerian\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old woman presents for a checkup. She is 20 weeks pregnant and has been admitted to the hospital multiple times during her pregnancy for seizures. She has a known seizure disorder but discontinued her valproic acid when she became pregnant. The patient's past medical history is otherwise unremarkable. She does not smoke, drink alcohol, or use any drugs. She generally prefers not to take medications and sees a shaman for her care typically. Given her recent hospitalization, the patient agrees to start carbamazepine. Which of the following is the most appropriate treatment for this patient at this time?", "answer": "Folate", "options": {"A": "Folate", "B": "Iron", "C": "Magnesium", "D": "Vitamin B12", "E": "Vitamin D"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 4-year-old boy is brought to the physician because of blisters and redness on his neck and chest for 2 days. He has also had a fever. He is lethargic and has not eaten well since the rash appeared. He has not had coughing, wheezing, or dysuria. He is an only child and there is no family history of serious illness. His immunizations are up-to-date. His temperature is 38.9°C (102°F), pulse is 90/min, and blood pressure is 80/40 mm Hg. Examination shows flaccid blisters over his neck and trunk that rupture easily. Areas of erythematous moist skin are also noted. Twirling an eraser over the trunk results in a blister. Oropharyngeal examination is normal. Laboratory studies show:\nHemoglobin 12 g/dL\nLeukocyte count 22,000/mm3\nSegmented neutrophils 77%\nEosinophils 3%\nLymphocytes 18%\nMonocytes 2%\nErythrocyte sedimentation rate 60 mm/h\nUrinalysis is normal. Which of the following is the most likely diagnosis?\"", "answer": "Staphylococcal scalded skin syndrome", "options": {"A": "Staphylococcal scalded skin syndrome", "B": "Pemphigus vulgaris", "C": "Scarlet fever", "D": "Bullous pemphigoid", "E": "Toxic epidermal necrolysis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 56-year-old woman comes to the emergency department because of a 3-day history of malaise, dysuria, blurred vision, and a painful, itchy rash. The rash began on her chest and face and spread to her limbs, palms, and soles. One week ago, she was diagnosed with trigeminal neuralgia and started on a new medicine. She appears ill. Her temperature is 38°C (100.4°F) and pulse is 110/min. Physical examination shows conjunctival injection and ulceration on the tongue and palate. There is no lymphadenopathy. Examination of the skin shows confluent annular, erythematous macules, bullae, and desquamation of the palms and soles. The epidermis separates when the skin is lightly stroked. Which of the following is the most likely diagnosis?", "answer": "Stevens-Johnson syndrome", "options": {"A": "Bullous pemphigoid", "B": "Stevens-Johnson syndrome", "C": "Pemphigus vulgaris", "D": "Drug-induced lupus erythematosus", "E": "DRESS syndrome"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman presents to her primary care physician for knee pain. The pain started yesterday and has not improved since then. The patient is generally in good health. She attends college and plays soccer for her school's team. Three days ago, she was slide tackled during a game and her leg was struck from the outside. She fell to the ground and sat out for the rest of the game. It was not until yesterday that she noticed swelling in her knee. She also feels as if her knee is unstable and does not feel confident bearing weight on her leg during athletic activities. Her past medical history is notable for asthma, which is currently treated with an albuterol inhaler. On physical exam, you note bruising over her leg, knee, and lateral thigh, and edema of her knee. Passive range of motion of the knee is notable only for minor clicking and catching of the joint. The patient's gait appears normal, though the patient states that her injured knee does not feel stable. Further physical exam is performed and imaging is ordered. Which of the following is the most likely diagnosis?", "answer": "Medial meniscal tear", "options": {"A": "Anterior cruciate ligament tear", "B": "Posterior cruciate ligament tear", "C": "Medial collateral ligament tear", "D": "Medial meniscal tear", "E": "Iliotibial band syndrome"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old man presents to the emergency department with abdominal pain that started 1 hour ago. The patient has a past medical history of diabetes and hypertension as well as a 40 pack-year smoking history. His blood pressure is 107/58 mmHg, pulse is 130/min, respirations are 23/min, and oxygen saturation is 98% on room air. An abdominal ultrasound demonstrates focal dilation of the aorta with peri-aortic fluid. Which of the following is the best next step in management?", "answer": "Emergent surgical intervention", "options": {"A": "Administer labetalol", "B": "Counsel the patient in smoking cessation", "C": "Emergent surgical intervention", "D": "Serial annual abdominal ultrasounds", "E": "Urgent surgery within the next day"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 15-year-old boy comes to the physician because of severe muscle cramps and pain for 3 months. He first noticed these symptoms while attending tryouts for the high school football team. Since then, he becomes easily fatigued and has severe muscle pain and swelling after 10 minutes of playing. However, after a brief period of rest, the symptoms improve, and he is able to return to the game. Two days ago, he had an episode of reddish-brown urine after playing football. There is no family history of serious illness. He appears healthy. Vital signs are within normal limits. Physical and neurological examinations show no abnormalities. Serum creatine kinase concentration is 333 U/L. Urinalysis shows:\nBlood 2+\nProtein negative\nGlucose negative\nRBC negative\nWBC 1–2/hpf\nWhich of the following is the most likely cause of this patient's symptoms?\"", "answer": "Myophosphorylase deficiency", "options": {"A": "Thyroid hormone deficiency", "B": "Dystrophin gene mutation", "C": "Myophosphorylase deficiency", "D": "Acid maltase deficiency", "E": "CTG repeat in the DMPK gene"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 82-year-old man who is currently being managed by the internal medicine service agrees to be examined by medical students as part of their training in physical examination. He is visited by a small group of medical students under the instruction of a preceptor and allows the students to make observations. They find that he has bibasilar crackles that are most prominent during inspiration as well as some wheezing. Furthermore, he coughs up some sputum during the exam, and this sputum is found to have a rust color. He does not report any pain and no skin findings are seen. Which of the following is most closely associated with the cause of this patient's physical exam findings?", "answer": "Left heart failure", "options": {"A": "Left heart failure", "B": "Long bone fractures", "C": "Protein C/S deficiency", "D": "Smoking", "E": "Tall, thin males"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2500-g (5.5-lb) male newborn is delivered at 35 weeks' gestation to a 25-year-old woman, gravida 2, para 1. The pregnancy was complicated by oligohydramnios. Pulse oximetry on room air shows an oxygen saturation of 78%. Examination in the delivery room shows that the newborn's skin appears blue with weak cry and irregular breathing and gasping. The nose is flat with bilateral epicanthal folds. The ears are low-set with broad auricles. The lower jaw is abnormally displaced backwards. The right lower limb appears shorter than the left lower limb with displaced right great toe. Breath sounds are decreased bilaterally. Renal ultrasound shows bilateral dilatation of the renal pelvis and ureters. Which of the following is most likely to confirm the underlying cause of this patient's condition?", "answer": "Voiding cystourethrogram", "options": {"A": "Voiding cystourethrogram", "B": "Echocardiography", "C": "Karyotyping", "D": "Blood cultures", "E": "X-ray of the chest\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 5-year-old girl presents to the physician with increased muscle cramping in her lower extremities after walking extended distances. The young girl is in the 10th percentile for height. Her past medical history is notable only for a cystic hygroma detected shortly after birth. Which of the following findings is most likely in this patient?", "answer": "Inferior erosion of the ribs", "options": {"A": "Decreased blood pressure in the upper and lower extremities", "B": "Barr bodies on buccal smear", "C": "Endocardial cushion defect", "D": "Inferior erosion of the ribs", "E": "Apparent hypertrophy of the calves"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old African American man comes to the doctor's office for an annual checkup. He feels healthy and his only concern is an occasional headache after work. Past medical history is significant for an appendectomy 10 years ago and a fractured arm playing football in high school. His mother has type 2 diabetes mellitus, while his father and grandfather both have hypertension. He does not drink alcohol, smoke cigarettes, or use drugs. His vital signs include: pulse 78/min and regular, respiratory rate 16/min, and temperature 36.8°C (98.2°F). Physical examination reveals an overweight African American man 167 cm (5 ft 6 in) tall and weighing 80 kg (176 lb) with a protuberant belly. BMI is 28.7 kg/m2. The remainder of the examination is unremarkable. During his last 2 visits, his blood pressure readings have been 140/86 mm Hg and 136/82 mm Hg. Today his blood pressure is 136/86 mm Hg and his laboratory tests show:\nSerum Glucose (fasting) 90.0 mg/dL\nSerum Electrolytes: \nSodium 142.0 mEq/L\nPotassium 3.9 mEq/L\nChloride 101.0 mEq/L\nSerum Creatinine 0.8 mg/dL\nBlood urea nitrogen 9.0 mg/dL\nUrinalysis:\nGlucose Negative\nKetones Negative\nLeukocytes Negative\nNitrite Negative\nRBCs Negative\nCasts Negative\nWhich of the following is the next best step in the management of this patient?", "answer": "Recommend weight loss, more exercise, and a salt-restricted diet.", "options": {"A": "Start him on lisinopril.", "B": "Start him on hydrochlorothiazide.", "C": "Order a glycosylated hemoglobin test (HbA1c).", "D": "Start him on hydrochlorothiazide and lisinopril together.", "E": "Recommend weight loss, more exercise, and a salt-restricted diet."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-year-old girl is brought to the physician with a 3-month history of progressive intermittent pain and swelling involving both knees, right ankle, and right wrist. The patient has been undergoing treatment with acetaminophen and ice packs, both of which relieved her symptoms. The affected joints feel \"stuck” and are difficult to move immediately upon waking up in the morning. However, the patient can move her joints freely after a few minutes. She also complains of occasional mild eye pain that resolves spontaneously. Five months ago, she was diagnosed with an upper respiratory tract infection that resolved without treatment. Vital signs are within normal limits. Physical examination shows swollen and erythematous joints, which are tender to touch. Slit-lamp examination shows an anterior chamber flare with signs of iris inflammation bilaterally. Laboratory studies show:\nBlood parameters\nHemoglobin 12.6 g/dL\nLeukocyte count 8,000/mm3\nSegmented neutrophils 76%\nEosinophils 1%\nLymphocytes 20%\nMonocytes 3%\nPlatelet count 360,000/mm3\nErythrocyte sedimentation rate 36 mm/hr\nSerum parameters\nAntinuclear antibodies 1:320\nRheumatoid factor negative\nWhich of the following is the most likely diagnosis?", "answer": "Oligoarticular juvenile idiopathic arthritis", "options": {"A": "Acute lymphocytic leukemia", "B": "Enthesitis-related arthritis", "C": "Oligoarticular juvenile idiopathic arthritis", "D": "Postinfectious arthritis", "E": "Seronegative polyarticular juvenile idiopathic arthritis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old woman with a past history of type 1 diabetes presents to your office with a 2-week history of vaginal itching and soreness accompanied by a white, clumpy vaginal discharge which she says resembles cheese curds. Her last HbA1c from a month ago was 7.8%, and her last cervical cytology from 10 months ago was reported as normal. She has a blood pressure of 118/76 mmHg, respiratory rate of 14/min, and heart rate of 74/min. Pelvic examination reveals multiple small erythematous lesions in the inguinal and perineal area, vulvar erythema, and excoriations. Inspection demonstrates a normal cervix and a white, adherent, thick, non-malodorous vaginal discharge. Which of the following is most likely to be present in a saline wet mount from the vaginal discharge of this patient?", "answer": "Hyphae", "options": {"A": "Motile flagellates", "B": "Clue cells on saline smear", "C": "Hyphae", "D": "Multinucleated giant cells", "E": "Gram-negative diplococci"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 33-year-old woman comes to the physician for the evaluation of bleeding from her gums for 2 weeks. These episodes occur spontaneously and are self-limiting. She has also had purplish skin lesions over her legs for 2 months. Last week, she had one episode of hematuria and watery diarrhea, both of which resolved without treatment. She has mild asthma. Her brother has hemophilia. Her only medication is a fenoterol inhaler. She appears healthy. Her temperature is 37.1°C (99.3°F), pulse is 88/min, respirations are 14/min, and blood pressure is 122/74 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender; there is no organomegaly. Oropharyngeal examination shows gingival bleeding. There are petechiae over the neck and the right upper extremity and purpuric spots over both lower extremities. Laboratory studies show:\nHemoglobin 13.3 mg/dL\nMean corpuscular volume 94 μm3\nLeukocyte count 8,800/mm3\nPlatelet count 18,000/mm3\nBleeding time 9 minutes\nProthrombin time 14 seconds (INR=0.9)\nPartial thromboplastin time 35 seconds\nSerum\nGlucose 88 mg/dL\nCreatinine 0.9 mg/dL\nWhich of the following is the most likely underlying mechanism of this patient's symptoms?\"", "answer": "IgG antibodies against platelets", "options": {"A": "Deficient Von Willebrand factor", "B": "Shiga-like toxin", "C": "Consumptive coagulopathy", "D": "IgG antibodies against platelets", "E": "Decrease in ADAMTS13 activity"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy is brought to the physician by his mother because of left-sided neck swelling that has slowly progressed over the past 4 weeks. He has no history of serious illness. Temperature is 38°C (100.4°F). Physical examination shows a non-tender, mobile mass in the left submandibular region with overlying erythema. A biopsy of the mass shows caseating granulomas. Pharmacotherapy with azithromycin and ethambutol is initiated. This patient is most likely to experience which of the following adverse effects related to ethambutol use?", "answer": "Color blindness", "options": {"A": "Orange urine", "B": "Acute kidney injury", "C": "Color blindness", "D": "Methemoglobinemia", "E": "Peripheral neuropathy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old boy is brought to the pediatrician by his parents with complaints of extra teeth in his lower and upper jaws. He was born by cesarean section at full term and his birth weight was 3.6 kg (7.9 lb). Until 6 months of age, he was breastfed and after that, solid foods were started. He did not cry immediately after birth, for which he was admitted to the intensive care unit where he also developed jaundice. There is a family history of intellectual disability. His motor milestones were delayed. His intelligence quotient (IQ) is 56. His temperature is 37.0ºC (98.6ºF), pulse is 88/min, and respiratory rate is 20/min. On physical examination, he has behavior disorders with autistic features, elongated face with large forehead, and prominent chin. His intraoral examination shows the presence of multiple teeth with crowding in both the upper and lower jaws, along with high arch palate and macroglossia. Genital examination reveals enlarged testicles. Panoramic radiographic examination shows teeth crowding in the maxillary and mandibular dental arches and congenital absence of some teeth. Which of the following is the most likely trinucleotide repeat that explains these findings?", "answer": "CGG", "options": {"A": "CGG", "B": "CAG", "C": "GAA", "D": "CTG", "E": "GCC"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old woman visits her physician with complaints of inability to become pregnant despite frequent unprotected sexual intercourse with her husband for over a year. She breastfed her only child until about 13 months ago, when the couple decided to have a second child. Over the past year, the patient has had only 4 episodes of menstrual bleeding. She reports occasional milk discharge from both breasts. Her only medication currently is daily pantoprazole, which she takes for dyspepsia. Her BMI is 29 kg/m2. Physical examination and vitals are normal. Pelvic examination indicates no abnormalities. The patient’s breast examination reveals full breasts and a few drops of milk can be expressed from both nipples. Estradiol, serum follicle-stimulating hormone (FSH), testosterone, and thyroid-stimulating hormone (TSH) levels are within the normal range. Which of the following best explains these findings?", "answer": "Prolactinoma", "options": {"A": "Pantoprazole", "B": "Primary ovarian insufficiency", "C": "Prolactinoma", "D": "Sheehan’s syndrome", "E": "Normal findings"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 53-year-old man is admitted to the intensive care unit from the emergency department with severe pancreatitis. Overnight, he starts to develop severe hypoxemia, and he is evaluated by a rapid response team. On exam the patient is breathing very quickly and has rales and decreased breath sounds bilaterally. He is placed on 50% FiO2, and an arterial blood gas is collected with the following results:\n\npH: 7.43\npCO2: 32 mmHg\npO2: 78 mmHg\n\nThe oxygen status of the patient continues to deteriorate, and he is placed on ventilator support. Which of the following would most likely be seen in this patient?", "answer": "Intra-alveolar hyaline membrane formation", "options": {"A": "Decreased lecithin to sphingomyelin ratio", "B": "Diffuse lipid droplets and globules", "C": "Hemosiderin-laden alveolar macrophages", "D": "Intra-alveolar hyaline membrane formation", "E": "Large clot in pulmonary artery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Several weeks after starting a new medication for rheumatoid arthritis, a 44-year-old woman comes to the physician because of painful ulcers in her mouth. Oral examination shows inflammation and swelling of the tongue and oropharynx and ulcers on the buccal mucosa bilaterally. Skin examination shows soft tissue swelling over her proximal interphalangeal joints and subcutaneous nodules over her elbows. Serum studies show an alanine aminotransferase level of 220 U/L, aspartate aminotransferase level of 214 U/L, and creatinine level of 1.7 mg/dL. Which of the following is the most likely primary mechanism of action of the drug she is taking?", "answer": "Inhibition of dihydrofolate reductase", "options": {"A": "Inhibition of thymidylate synthase", "B": "Inhibition of dihydrofolate reductase", "C": "Inhibition of inosine monophosphate dehydrogenase", "D": "Inhibition of cyclooxygenase", "E": "Inhibition of NF-κB"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old man comes to the physician for a routine health maintenance examination. His wife has noticed that his left eye looks smaller than his right eye. He has had left shoulder and arm pain for 3 months. He has hypertension and coronary artery disease. Current medications include enalapril, metoprolol, aspirin, and atorvastatin. His medical history is significant for gonorrhea, for which he was treated in his 30's. He has smoked two packs of cigarettes daily for 35 years. He does not drink alcohol. His temperature is 37°C (98.6°F), pulse is 71/min, and blood pressure is 126/84 mm Hg. The pupils are unequal; when measured in dim light, the left pupil is 3 mm and the right pupil is 5 mm. There is drooping of the left eyelid. The remainder of the examination shows no abnormalities. Application of apraclonidine drops in both eyes results in a left pupil size of 5 mm and a right pupil size of 4 mm. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the chest", "options": {"A": "Applanation tonometry", "B": "Erythrocyte sedimentation rate", "C": "Rapid plasma reagin", "D": "CT scan of the chest", "E": "Anti-acetylcholine receptor antibodies"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old man is brought to the emergency department after his girlfriend found him twitching and jerking in the yard while gardening. Shortly after he became obtunded, emergency medical services reported 1 episode of emesis during transport. His blood pressure is 85/50 mmHg, pulse is 55/min, and respirations are irregular. Physical examination demonstrates marks on his left forearm, pinpoint pupils, diaphoresis, and fasciculations of his left calf. Following initial stabilization and respiratory support, what is the best next step?", "answer": "Atropine and pralidoxime", "options": {"A": "Atropine", "B": "Atropine and pralidoxime", "C": "Lamotrigine", "D": "Naloxone", "E": "Naltrexone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 73-year-old female presents to you for an office visit with complaints of getting lost. The patient states that over the last several years, the patient has started getting lost in places that she is familiar with, like in her neighborhood while driving to her church. She has also has difficulty remembering to pay her bills. She denies any other complaints. Her vitals are normal, and her physical exam does not reveal any focal neurological deficits. Her mini-mental status exam is scored 19/30. Work up for secondary causes of cognitive decline is negative. Which of the following should be included in the patient's medication regimen to slow the progression of disease?", "answer": "Memantine", "options": {"A": "Ropinirole", "B": "Memantine", "C": "Bromocriptine", "D": "Pramipexole", "E": "Pergolide"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old man comes to the physician because of a 10-month history of progressive shortness of breath and a cough productive of a small amount of white phlegm. Bilateral end-expiratory wheezing is heard on auscultation of the chest. Pulmonary function tests show total lung capacity that is 108% of predicted, an FEV1 that is 56% of predicted, and an FEV1:FVC ratio of 62%. Which of the following interventions is most likely to slow the decline in FEV1 in this patient?", "answer": "Smoking cessation", "options": {"A": "Smoking cessation", "B": "Breathing exercises", "C": "Salmeterol therapy", "D": "Fluticasone therapy", "E": "Alpha-1 antitrypsin therapy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman survives a plane crash in the Arctic region of Alaska. She is unable to recover any food from the crash site but is able to melt snow into drinking water using a kettle and a lighter. A rescue helicopter finally finds her after 12 days, and she is flown to a hospital. At this time, which of the following substances is mostly responsible for supplying her brain with energy?", "answer": "Acetoacetate", "options": {"A": "Acetoacetate", "B": "Amino acids", "C": "Cholesterol", "D": "Free fatty acids", "E": "Glucose"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old woman presents to the emergency department with a 2-week history of dry cough and shortness of breath on exertion. She says that she has also been feeling joint pain that has been increasing over time and is worst in the mornings. Finally, she has noticed painful swellings that have been appearing on her body over the last month. Her past medical history is significant for childhood asthma that does not require any current medications. She drinks socially and has smoked 2 packs per day since she was 16 years old. Physical exam reveals erythematous nodular lesions on her trunk and upper extremities. Serum protein electrophoresis shows polyclonal gammopathy. Which of the following would most likely also be seen in this patient?", "answer": "Noncaseating granulomas", "options": {"A": "Acid-fast rods", "B": "Antibodies to small nuclear ribonucleoproteins", "C": "Golden-brown fusiform rods", "D": "Macrophages with black phagocytosed particles", "E": "Noncaseating granulomas"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old man comes to the emergency department because of progressive abdominal swelling and shortness of breath for 1 week. He drinks 12 to 13 alcoholic beverages daily. He appears emaciated. Examination shows pallor, jaundice, hepatomegaly, gynecomastia, and a protuberant abdomen with a fluid wave and shifting dullness. Periodic monitoring of which of the following markers is most appropriate for this patient?", "answer": "Alpha-fetoprotein", "options": {"A": "S-100 protein", "B": "Alpha-fetoprotein", "C": "Carcinoembryonic antigen", "D": "Cancer antigen 19-9", "E": "Beta-human chorionic gonadotropin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 7-month-old boy is brought to the pediatrician by his parents due to progressively worsening weakness for the last three months. The parents also describe the boy as having an exaggerated response when startled as well as diminishing response to visual stimuli. At birth, the boy was healthy and remained as such for the first few months of life. The mother says pregnancy was unremarkable, and the boy was born at 39 weeks with no complications during delivery. He is up to date on his vaccinations. The boy's grandparents immigrated from an eastern European country. Physical examination reveals hyperreflexia. Abdominal examination reveals no abnormalities. On fundoscopy, the following is seen. Which of the following is most likely deficient in this patient?", "answer": "Hexosaminidase A", "options": {"A": "α-Galactosidase", "B": "ß-Glucosidase", "C": "Hexosaminidase A", "D": "Hexosaminidase B", "E": "Arylsulfatase A"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old man presents to the clinic for a regular health checkup. He is hypertensive and was diagnosed with congestive heart failure last year. He has hyperlipidemia but does not take any medication for it. Although he takes his antihypertensive medications regularly, his blood pressure recordings at home tend to range between 150/98 and 160/90 mm Hg. Today, his blood pressure is 147/96 mm Hg. The doctor decides to add indapamide to his medication list and asks the patient to follow up within 2 weeks. The patient is compliant with the medication. He comes back to the physician in just one week complaining of muscle cramping and weakness. Which of the following is the most likely cause of his symptoms?", "answer": "Hypokalemia", "options": {"A": "Hypocalcemia", "B": "Hypoglycemia", "C": "Hyperlipidemia", "D": "Hyperuricemia", "E": "Hypokalemia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old female presents to her PCP at the request of her husband after 3 weeks of erratic behavior. The patient has been staying up all night online shopping on eBay. Despite a lack of sleep, she is \"full of energy\" during the day at her teaching job, which she believes is \"beneath [her], anyway.\" She has not sought psychiatric treatment in the past, but reports an episode of self-diagnosed depression 2 years ago. The patient denies thoughts of suicide. Pregnancy test is negative. Which of the following is the best initial treatment?", "answer": "Valproate and olanzapine", "options": {"A": "Valproate", "B": "Valproate and venlafaxine", "C": "Valproate and olanzapine", "D": "Haloperidol", "E": "Electroconvulsive therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 10-day-old newborn is undergoing surgery for the removal of a branchial cleft cyst. Histopathology of the cyst shows squamous cells with lymphoid infiltrate and keratinaceous cellular debris embedded in adipose tissue with a high concentration of mitochondria. Which of the following substances is most likely to be found within these mitochondria?", "answer": "Thermogenin", "options": {"A": "Thermogenin", "B": "Leptin", "C": "Kinesin", "D": "Ubiquitin", "E": "Clathrin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old physician is cleaning his pool when he splashes the hydrochloric acid in his left eye. He feels immediate pain and burning. His eye starts to tear profusely, and he can barely open it. His medical history is significant for psoriasis. He is farsighted and has glasses for reading and computer work. He uses topical calcipotriene and topical triamcinolone as needed. His only surgery was a tonsillectomy as a child. He is married and has one son who is healthy. His mother has Graves disease. He drinks a glass of wine with dinner but denies tobacco or recreational drug use. Which of the following is the best initial step in management?", "answer": "Irrigate with tap water", "options": {"A": "Apply topical bacitracin", "B": "Call the patient’s ophthalmologist", "C": "Go to the emergency department immediately", "D": "Irrigate with alkali solution", "E": "Irrigate with tap water"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A previously healthy 31-year-old woman comes to the emergency department because of sudden, severe epigastric pain and vomiting for the past 4 hours. She reports that the pain radiates to the back and began when she was having dinner and drinks at a local brewpub. Her temperature is 37.9°C (100.2°F), pulse is 98/min, respirations are 19/min, and blood pressure is 110/60 mm Hg. Abdominal examination shows epigastric tenderness and guarding but no rebound. Bowel sounds are decreased. Laboratory studies show:\nHematocrit 43%\nLeukocyte count 9000/mm3\nSerum\nNa+ 140 mEq/L\nK+ 4.5 mEq/L\nCa2+ 9.0 mg/dL\nLipase 170 U/L (N = < 50 U/L)\nAmylase 152 U/L\nAlanine aminotransferase (ALT, GPT) 140 U/L\nIntravenous fluid resuscitation is begun. Which of the following is the most appropriate next step in management?\"", "answer": "Right upper quadrant abdominal ultrasound", "options": {"A": "Contrast-enhanced abdominal CT scan", "B": "Right upper quadrant abdominal ultrasound", "C": "Plain x-ray of the abdomen", "D": "Measure serum triglycerides", "E": "Blood alcohol level assay"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 54-year-old man with a history of hyperlipidemia presents to the emergency department complaining of left sided chest pain. He says the pain began 3 hours ago while he was cooking dinner in his kitchen. The pain radiates to his left arm and stomach. He also complains of feeling anxious and heart palpitations. Temperature is 98.7°F (37.1°C), blood pressure is 130/80 mmHg, pulse is 101/min, and respirations are 22/min. Inspection demonstrates a diffuse diaphoresis, and cardiac auscultation reveals an S4 gallop. Cardiac catheterization reveals occlusion of the left anterior descending artery, and a vascular stent is placed. The patient is discharged on aspirin, atorvastatin, and an antiplatelet medication. Which of the following is the mechanism of action of the most likely prescribed antiplatelet medication?", "answer": "Irreversible ADP receptor antagonism", "options": {"A": "Antithrombin III activation", "B": "Direct factor Xa inhibition", "C": "GPIIb/IIIa inhibition", "D": "Irreversible ADP receptor antagonism", "E": "Reversible ADP receptor antagonism"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old Caucasian female with a long history of uncontrolled migraines presents to general medical clinic with painless hematuria. She is quite concerned because she has never had symptoms like this before. Vital signs are stable, and her physical examination is benign. She denies any groin pain, flank pain, or costovertebral angle tenderness. She denies any recent urinary tract infections or dysuria. Urinary analysis confirms hematuria and a serum creatinine returns at 3.0. A renal biopsy reveals papillary necrosis and a tubulointerstitial infiltrate. What is the most likely diagnosis?", "answer": "Analgesic nephropathy", "options": {"A": "Analgesic nephropathy", "B": "Kidney stone", "C": "Bladder cancer", "D": "Kidney cancer", "E": "Sickle cell disease"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 38-year-old man comes to the physician because of a 2-week history of abdominal pain and an itchy rash on his buttocks. He also has fever, nausea, and diarrhea with mucoid stools. One week ago, the patient returned from Indonesia, where he went for vacation. Physical examination shows erythematous, serpiginous lesions located in the perianal region and the posterior thighs. His leukocyte count is 9,000/mm3 with 25% eosinophils. Further evaluation is most likely to show which of the following findings?", "answer": "Rhabditiform larvae on stool microscopy", "options": {"A": "Rhabditiform larvae on stool microscopy", "B": "Oocysts on acid-fast stool stain", "C": "Giardia lamblia antibodies on stool immunoassay", "D": "Branching septate hyphae on KOH preparation", "E": "Entamoaeba histolytica antibodies on stool immunoassay"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman comes to the physician because of headaches, irregular menses, and nipple discharge for the past 4 months. Breast examination shows milky white discharge from both nipples. Her thyroid function tests and morning cortisol concentrations are within the reference ranges. A urine pregnancy test is negative. An MRI of the brain is shown. Which of the following sets of changes is most likely in this patient?\n $$$ Serum estrogen %%% Serum progesterone %%% Dopamine synthesis $$$", "answer": "↓ ↓ ↑", "options": {"A": "↔ ↔ ↔", "B": "↑ ↔ ↔", "C": "↓ ↓ ↓", "D": "↓ ↓ ↑", "E": "↑ ↑ ↔"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old woman visits her local walk-in clinic and reports more than one week of progressive shortness of breath, dyspnea on effort, fatigue, lightheadedness, and lower limb edema. She claims she has been healthy all year round except for last week when she had a low-grade fever, malaise, and myalgias. Upon examination, her blood pressure is 94/58 mm Hg, heart rate is 125/min, respiratory rate is 26/min, and body temperature is 36.4°C (97.5°F). Her other symptoms include fine rattles in the base of both lungs, a laterally displaced pulse of maximum intensity, and regular, rhythmic heart sounds with an S3 gallop. She is referred to the nearest hospital for stabilization and further support. Which of the following best explains this patient’s condition?", "answer": "Disruption of the dystrophin-glycoprotein complex", "options": {"A": "Disruption of the dystrophin-glycoprotein complex", "B": "Cardiomyocyte hypertrophy", "C": "Fibrofatty replacement of the myocardium", "D": "IgA antiendomysial antibodies", "E": "Eosinophilic infiltration"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 46-year-old woman comes to the physician for a routine health maintenance examination. She feels well. She has a history of seizures controlled with levetiracetam. She has needed glasses for the past 13 years. Her father died of pancreatic cancer. She is 175 cm (5 ft 9 in) tall and weighs 79 kg (174 lbs); BMI is 25.8 kg/m2. Vital signs are within normal limits. A photograph of the face is shown. This patient is most likely to be at increased risk for which of the following conditions?", "answer": "Coronary artery disease", "options": {"A": "Optic glioma", "B": "Squamous cell carcinoma", "C": "Gastric cancer", "D": "Coronary artery disease", "E": "Renal angiomyolipoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old man presents to his physician with the complaint of bilateral lower back pain. The pain is 5/10, constant, aching, aggravated by bending forward and lying supine, and is alleviated by resting in a neutral position. The pain appeared 3 days ago after the patient overstrained at the gym. He does not report changes in sensation or limb weakness. The patient works as a business analyst. The patient’s weight is 88 kg (194 lb), and the height is 186 cm (6 ft 1 in). The vital signs are within normal limits. The neurological examination shows equally normal lower limb reflexes, and preserved muscle tone and power. The paravertebral palpation of the lumbar region increases the pain. Which of the following non-pharmacological interventions is the most appropriate in the presented case?", "answer": "Maintaining usual activity as tolerated", "options": {"A": "Bed rest for 3 days", "B": "Manual traction", "C": "Maintaining usual activity as tolerated", "D": "Therapeutic ultrasonography", "E": "Electromyographic biofeedback"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 16-year-old boy comes to the physician with a 4-day history of sore throat and mild fever. He is on the varsity soccer team at his high school, but has been unable to go to practice for the last few days because he has been very tired and is easily exhausted. He has no history of serious illness and takes no medications. His mother has type 2 diabetes mellitus. He appears weak and lethargic. His temperature is 38.7°C (101.7°F), pulse is 84/min, and blood pressure is 116/78 mm Hg. Examination shows enlarged, erythematous, and exudative tonsils; posterior cervical lymphadenopathy is present. Abdominal examination shows no abnormalities. His hemoglobin concentration is 14.5 g/dL and leukocyte count is 11,200/mm3 with 48% lymphocytes. A heterophile antibody test is positive. In addition to supportive therapy, which of the following is the most appropriate next step in management?", "answer": "Write a medical note that excuses from soccer events", "options": {"A": "Write a medical note that excuses from soccer events", "B": "Oral amoxicillin therapy", "C": "Oral corticosteroid therapy", "D": "Intravenous acyclovir therapy", "E": "Intravenous foscarnet therapy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 54-year-old woman presents to her primary care physician complaining of watery diarrhea for the last 3 weeks. She reports now having over 10 bowel movements per day. She denies abdominal pain or rash. A basic metabolic profile is notable for the following: Na: 127 mEq/L; K 2.1 mEq/L; Glucose 98 mg/dL. Following additional work-up, octreotide was started with significant improvement in symptoms and laboratory values. Which of the following is the most likely diagnosis?", "answer": "VIPoma", "options": {"A": "VIPoma", "B": "Glucagonoma", "C": "Somatostatinoma", "D": "Insulinoma", "E": "Gastrinoma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 16-year-old girl is brought to the physician by her mother because she has not attained menarche. She has no history of serious illness. She is at 50th percentile for height and weight. Examination shows no breast glandular tissue and no pubic hair development. The remainder of the examination shows no abnormalities. A urine pregnancy test is negative. An ultrasound of the pelvis shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Serum FSH level", "options": {"A": "GnRH stimulation test", "B": "Reassurance", "C": "Progesterone challenge test", "D": "Serum FSH level", "E": "Serum testosterone level"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old Caucasian male presents to your office with an 8 mm dark lesion on his back. The lesion, as seen below, has irregular borders and marked internal color variation. Upon excisional biopsy, the presence of which of the following would best estimate the risk of metastasis in this patient’s lesion:", "answer": "Vertical tumor growth", "options": {"A": "Palisading nuclei", "B": "Keratin pearls", "C": "Vertical tumor growth", "D": "Cellular atypia", "E": "Increased production of melanosomes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old child is brought to a pediatric clinic by his mother for a rash that started a few days ago. The mother adds that her son has also had a fever and sore throat since last week. His immunizations are up to date. On examination, a rash is present over the trunk and upper extremities and feels like sandpaper to touch. An oropharyngeal examination is suggestive of exudative pharyngitis with a white coat over the tongue. The physician swabs the throat and uses the swab in a rapid antigen detection test kit. He also sends the sample for microbiological culture. The physician then recommends empiric antibiotic therapy and tells the mother that if the boy is left untreated, the likelihood of developing a complication later in life is very high. Which of the following best explains the mechanism underlying the development of the complication the physician is talking about?", "answer": "Molecular mimicry", "options": {"A": "Antigenic shift", "B": "Bacterial tissue invasion", "C": "Molecular mimicry", "D": "Toxin-mediated cellular damage", "E": "Genetic drift"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 19-year-old man with unknown medical history is found down on a subway platform and is brought to the hospital by ambulance. He experiences two episodes of emesis en route. In the emergency department, he appears confused and is complaining of abdominal pain. His temperature is 37.0° C (98.6° F), pulse is 94/min, blood pressure is 110/80 mmHg, respirations are 24/min, oxygen saturation is 99% on room air. His mucus membranes are dry and he is taking rapid, deep breathes. Laboratory work is presented below:\n\nSerum:\nNa+: 130 mEq/L\nK+: 4.3 mEq/L\nCl-: 102 mEq/L\nHCO3-: 12 mEq/L\nBUN: 15 mg/dL\nGlucose: 362 mg/dL\nCreatinine: 1.2 mg/dL\nUrine ketones: Positive\n\n\nThe patient is given a bolus of isotonic saline and started on intravenous insulin drip. Which of the following is the most appropriate next step in management?", "answer": "Intravenous potassium chloride", "options": {"A": "Subcutaneous insulin glargine", "B": "Intravenous isotonic saline", "C": "Intravenous sodium bicarbonate", "D": "Intravenous potassium chloride", "E": "Intravenous 5% dextrose and 1/2 isotonic saline"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A physiologist is studying various mediators that modulate coronary circulation. He is particularly looking at mediators that are activated via the clotting cascade, primarily activated factor XII. He finds that when the clotting cascade starts, it leads to the activation of factor XII, which in turn activates the enzyme kallikrein. This enzyme activates high and low-molecular-weight precursors of certain mediators, which work by contracting the visceral smooth muscle while relaxing the vascular smooth muscle. They are primarily associated with hypersensitivity and can cause an increase in capillary permeability, pain, and mobilize leukocytes. Which of the following is the precursor protein for the mediators the physiologist is studying?", "answer": "Kininogen", "options": {"A": "L-Arginine", "B": "Arachidonic acid", "C": "Hydroxytryptophan", "D": "Kininogen", "E": "Prothrombin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 61-year-old man presents with gradually increasing shortness of breath. For the last 2 years, he has had a productive cough on most days. Past medical history is significant for hypertension and a recent admission to the hospital for pneumonia. He uses a triamcinolone inhaler and uses an albuterol inhaler as a rescue inhaler. He also takes lisinopril and a multivitamin daily. He has smoked a pack a day for the last 32 years and has no intention to quit now. Today, his blood pressure is 142/97 mm Hg, heart rate is 97/min, respiratory rate is 22/min, and temperature is 37.4°C (99.3°F). On physical exam, he has tachypnea and has some difficulty finishing his sentences. His heart has a regular rate and rhythm. Auscultation of his lungs reveals wheezing and rhonchi that improves after a deep cough. Fremitus is absent. Pulmonary function tests show FEV1/FVC of 55% with no change in FEV1 after albuterol treatment. Which of the following is the most likely pathology associated with this patients disease?", "answer": "Inflamed bronchus with hypertrophy and hyperplasia of mucous glands", "options": {"A": "Permanent bronchial dilation", "B": "Chronic granulomatous inflammation with bilateral hilar lymphadenopathy", "C": "Airway hypersensitivity", "D": "Inflamed bronchus with hypertrophy and hyperplasia of mucous glands", "E": "Consolidation and red hepatization"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old boy is brought to the physician for presurgical evaluation before undergoing splenectomy. One year ago, he was diagnosed with hereditary spherocytosis and has received 6 blood transfusions for severe anemia since then. His only medication is a folate supplement. Immunizations are up-to-date. His temperature is 36.7°C (98°F), pulse is 115/min, respirations are 24/min, and blood pressure is 110/60 mm Hg. Examination shows conjunctival pallor and jaundice. The spleen tip is palpated 5 cm below the left costal margin. Which of the following is the most appropriate recommendation to prevent future morbidity and mortality in this patient?", "answer": "Daily penicillin prophylaxis", "options": {"A": "Subcutaneous injection of deferoxamine", "B": "Vaccination against hepatitis B virus", "C": "Daily penicillin prophylaxis", "D": "Daily warfarin prophylaxis", "E": "Administration of hydroxyurea"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old boy presents with a history of recurrent bacterial infections, including several episodes of pneumococcal sepsis. His 2 maternal uncles died after having had similar complaints. Lab investigations reveal an undetectable level of all serum immunoglobulins. Which of the following is the most likely diagnosis of this patient?", "answer": "Bruton agammaglobulinemia", "options": {"A": "Common variable immunodeficiency", "B": "Hereditary angioedema", "C": "Chediak-Higashi syndrome", "D": "Bruton agammaglobulinemia", "E": "DiGeorge syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 63-year-old man is brought to the emergency department for evaluation of abdominal pain. The pain started four days ago and is now a diffuse crampy pain with an intensity of 6/10. The patient has nausea and has vomited twice today. His last bowel movement was three days ago. He has a history of hypertension and recurrent constipation. Five years ago, he underwent emergency laparotomy for a perforated duodenal ulcer. His father died of colorectal cancer at the age of 65 years. The patient has been smoking one pack of cigarettes daily for the past 40 years. Current medications include lisinopril and lactulose. His temperature is 37.6°C (99.7°F), pulse is 89/min, and blood pressure is 120/80 mm Hg. Abdominal examination shows distention and mild tenderness to palpation. There is no guarding or rebound tenderness. The bowel sounds are high-pitched. Digital rectal examination shows no abnormalities. An x-ray of the abdomen is shown. In addition to fluid resuscitation, which of the following is the most appropriate next step in the management of this patient?", "answer": "Nasogastric tube placement and bowel rest", "options": {"A": "Ciprofloxacin and metronidazole", "B": "PEG placement and enteral feeding", "C": "Colonoscopy", "D": "Nasogastric tube placement and bowel rest", "E": "Surgical bowel decompression"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old man comes to the emergency department because of a painful rash for 2 days. The rash initially appeared on his left lower abdomen and has spread to the rest of the abdomen and left upper thigh over the last 24 hours. Pain is exacerbated with movement. He initially thought the skin rash was an allergic reaction to a new laundry detergent, but it did not respond to over-the-counter antihistamines. Six weeks ago, the patient was diagnosed with Hodgkin's lymphoma and was started on doxorubicin, bleomycin, vinblastine, and dacarbazine. He is sexually active with one female partner and uses condoms for contraception. His temperature is 37.9°C (100.2°F), pulse is 80/min, and blood pressure is 117/72 mm Hg. Examination shows two markedly enlarged cervical lymph nodes. A photograph of the rash is shown. Which of the following is the most appropriate next step in management?", "answer": "Inpatient treatment with intravenous acyclovir", "options": {"A": "Outpatient treatment with oral penicillin V", "B": "Inpatient treatment with oral ivermectin", "C": "Outpatient treatment with topical permethrin", "D": "Inpatient treatment with intravenous acyclovir", "E": "Inpatient treatment with intravenous ceftriaxone\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old man with seizure disorder is brought to the emergency department by his girlfriend after falling while climbing a building. The girlfriend reports that he was started on a new medication for treatment of depressed mood, low energy, and difficulty sleeping 2 weeks ago by his physician. She says that he has had unstable emotions for several months. Over the past 3 days, he has not slept and has spent all his time “training to climb Everest.” He has never climbed before this period. He also spent all of his savings buying mountain climbing gear. Physical examination shows ecchymoses over his right upper extremity, pressured speech, and easy distractibility. He is alert but not oriented to place. Which of the following drugs is the most likely cause of this patient's current behavior?", "answer": "Venlafaxine", "options": {"A": "Lithium", "B": "Quetiapine", "C": "Bupropion", "D": "Venlafaxine", "E": "Selegiline"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 16-year-old boy is brought to the emergency department 20 minutes after collapsing while playing basketball. There is no personal or family history of serious illness. On arrival, there is no palpable pulse and no respiratory effort is seen. He is declared dead. The family agrees to an autopsy. Which of the following is most likely to be found in this patient?", "answer": "Interventricular septal hypertrophy", "options": {"A": "Defect in the atrial septum", "B": "Postductal narrowing of the aorta", "C": "Atheromatous plaque rupture", "D": "Interventricular septal hypertrophy", "E": "Pericardial fluid collection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old man comes to the physician because of worsening lower back pain for 6 weeks. He reports that the pain is most intense with movement and that it sometimes occurs at night. Over the past 3 months, he has noticed a weakened urinary stream. He has not seen any blood in his urine. His only daily medication is ibuprofen. Examination shows no spinal deformities. Palpation of the lumbar spinal process elicits tenderness. Muscle strength is normal. Which of the following is the most likely cause of this patient’s back pain?", "answer": "Malignancy", "options": {"A": "Malignancy", "B": "Lumbar spinal stenosis", "C": "Osteoporosis", "D": "Disc herniation", "E": "Lumbar strain"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 47-year-old woman presents to her primary care physician for a wellness checkup. The patient states that she currently feels well and has no complaints. She has failed multiple times at attempting to quit smoking and has a 40 pack-year smoking history. She drinks 4 alcoholic beverages every night. The patient is currently taking a multivitamin and vitamin D supplements. She has also attempted to eat more salmon given that she has heard of its health benefits. Physical exam is notable for back stiffness on mobility testing. The patient states that she frequently has back pain when sitting. Laboratory values are obtained as seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 12.2 mg/dL\nPTH: 75 pg/mL (normal 10 - 65 pg/mL)\n\nUrine:\nColor: Yellow\npH: 7.0\nBlood: 1+\nProtein: Negative\nNitrite: Positive\nBacteria: Positive\nCa2+: Low\nBenzodiazepines: Positive\n\nWhich of the following is the best explanation for this patient’s electrolyte abnormalities?", "answer": "Familial hypocalciuric hypercalcemia", "options": {"A": "Familial hypocalciuric hypercalcemia", "B": "Hyperparathyroidism", "C": "Hypervitaminosis D", "D": "Multiple myeloma", "E": "Renal cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 73-year-old man comes to the physician at his wife's insistence because of a skin lesion on his back. He lives with his wife and works for a high-profile law firm where he represents several major clients. Physical examination shows a 7-mm, brownish-black papule with irregular borders. When the doctor starts to mention possible diagnoses, the patient interrupts her and says that he does not want to know the diagnosis and that she should just do whatever she thinks is right. A biopsy of the skin lesion is performed and histological examination shows clusters of infiltrative melanocytes. Upon repeat questioning, the patient reaffirms his wish to not know the diagnosis. Which of the following is the most appropriate response from the physician?", "answer": "\"\"\"I would like to know more about why you don't want to hear your test results.\"\"\"", "options": {"A": "\"\"\"I have a moral obligation as a physician to inform you about the diagnosis.\"\"\"", "B": "\"\"\"I would like to do further testing to investigate how far this cancer has spread.\"\"\"", "C": "\"\"\"I don't have to tell you, but I will have to tell your wife so we can plan your therapy.\"\"\"", "D": "\"\"\"I'll have to consult with the ethics committee to determine further steps.\"\"\"", "E": "\"\"\"I would like to know more about why you don't want to hear your test results.\"\"\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man comes to the physician for a follow-up examination. He feels well. He has hyperlipidemia and type 2 diabetes mellitus. He takes medium-dose simvastatin and metformin. Four months ago, fasting serum studies showed a LDL-cholesterol of 136 mg/dL and his medications were adjusted. Vital signs are within normal limits. On physical examination, there is generalized weakness of the proximal muscles. Deep tendon reflexes are 2+ bilaterally. Fasting serum studies show:\nTotal cholesterol 154 mg/dL\nHDL-cholesterol 35 mg/dL\nLDL-cholesterol 63 mg/dL\nTriglycerides 138 mg/dL\nGlucose 98 mg/dL\nCreatinine 1.1 mg/dL\nCreatine kinase 260 mg/dL\nWhich of the following is the most appropriate next step in management of this patient's hyperlipidemia?\"", "answer": "Discontinue simvastatin, start pravastatin in 3 weeks", "options": {"A": "Discontinue simvastatin, start pravastatin in 3 weeks", "B": "Continue simvastatin, add niacin", "C": "Discontinue simvastatin, start fenofibrate now", "D": "Increase the dose of simvastatin", "E": "Discontinue simvastatin, start niacin in 3 weeks"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-year-old girl presents with four days of malaise, painful joints, nodular swelling over her elbows, low-grade fever, and a rash on her chest and left shoulder. Two weeks ago, she complained of a sore throat that gradually improved but was not worked up. She was seen for a follow-up approximately one week later. At this visit her cardiac exam was notable for a late diastolic murmur heard best at the apex in the left lateral decubitus position with no radiation. Which of the following is the best step in the management of this patient?", "answer": "Penicillin therapy", "options": {"A": "Penicillin therapy", "B": "NSAIDS for symptomatic relief", "C": "Aortic valve replacement", "D": "Mitral valve repair", "E": "Reassurance that this is a benign murmur and send home"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old girl is brought to the pediatrician by her parents who are concerned that she is not developing normally. They say she does not talk and avoids eye contact. She prefers to sit and play with blocks by herself rather than engaging with other children. They also note that she will occasionally have violent outbursts in inappropriate situations. She is otherwise healthy. In the office, the patient sits quietly in the corner of the room stacking and unstacking blocks. Examination of the patient shows a well-developed female with no physical abnormalities. Which of the following is the most likely diagnosis in this patient?", "answer": "Autism spectrum disorder", "options": {"A": "Autism spectrum disorder", "B": "Cri-du-chat syndrome", "C": "Fragile X syndrome", "D": "Oppositional defiant disorder", "E": "Rett syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 82-year-old man—a retired physics professor—presents with progressive difficulty walking. He has bilateral knee osteoarthritis and has used a walker for the past several years. For the past 6 months, he has experienced problems walking and maintaining balance and has been wheelchair-bound. He has fallen several times, hitting his head a few times but never losing consciousness. He complains of occasional difficulty remembering names and phone numbers, but his memory is otherwise fine. He also complains of occasional incontinence. Physical examination reveals a slow wide-based gait with small steps and intermittent hesitation. He scores 22 out of 30 on the Mini-Mental State Examination (MMSE). A brain MRI demonstrates dilated ventricles with high periventricular fluid-attenuated inversion recovery (FLAIR) signal. A large-volume lumbar puncture improves his gait. Which of the following is the most likely risk factor for the development of this condition?", "answer": "Subarachnoid hemorrhage", "options": {"A": "Alzheimer’s disease", "B": "Diabetes mellitus", "C": "Epilepsy", "D": "Hypertension", "E": "Subarachnoid hemorrhage"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 44-year-old man presents to his primary care physician for muscle pain and weakness. He says that his muscle pain mainly affects his legs. He also experiences difficulty with chewing gum and has poor finger dexterity. Medical history is significant for infertility and cataracts. On physical exam, the patient's face is long and narrow with a high arched palate and mild frontal balding. There is bilateral ptosis and temporalis muscle and sternocleidomastoid muscle wasting. Creatine kinase level is mildly elevated. Which of the following is most likely to be found on genetic testing?", "answer": "DMPK gene CTG expansion", "options": {"A": "DMPK gene CTG expansion", "B": "DYSF gene missense mutation", "C": "Dystrophin gene nonsense mutation", "D": "Dystrophin gene non-frameshift mutation", "E": "No genetic abnormality"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 10-year-old boy is brought to the pediatric clinic because of a sore throat of 1-week duration. He also has a cough and fever. He has pain when swallowing and sometimes water regurgitates from his nose when drinking. He was diagnosed with acute tonsillitis by his primary care physician 1 month ago, for which he received a week-long course of amoxicillin. His immunization status is unknown as he recently moved to the US from Asia. On examination, he is alert and oriented to time, place, and person. On inspection of his oral cavity, an edematous tongue with a grey-white membrane on the soft palate and tonsils is noted. The neck is diffusely swollen with bilateral tender cervical lymphadenopathy. Which of the following is the cause of this patient’s condition and could have been prevented through vaccinations in childhood?", "answer": "Corynebacterium diphtheriae", "options": {"A": "Streptococcus pyogenes", "B": "Corynebacterium diphtheriae", "C": "Haemophilus influenzae b", "D": "Agranulocytosis", "E": "Epstein Barr virus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old woman comes to the emergency room with chest pain. She describes the pain as a squeezing sensation in her chest with radiation to the left shoulder. The episode began about 15 minutes ago when she was sitting reading a book. She has had this pain before, typically in the evenings, though prior episodes usually resolved after a couple of minutes. Her pulse is 112/min, blood pressure is 121/87 mmHg, and respiratory rate is 21/min. An ECG shows ST-segment elevations in the inferior leads. Serum troponins are negative on two successive blood draws and the ECG shows no abnormalities 30 minutes later. Which of the following is the best long-term treatment for this patient's symptoms?", "answer": "Diltiazem", "options": {"A": "Clopidogrel", "B": "Diltiazem", "C": "Aspirin", "D": "Enalapril", "E": "Metoprolol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old man is brought to the emergency department because of progressive weakness of his lower extremities and urinary incontinence for the past 2 weeks. Over the past 2 months, he has had increasing back pain. His temperature is 37.1°C (98.8°F), pulse is 88/min, and blood pressure is 106/60 mm Hg. Examination shows an ataxic gait. Muscle strength is decreased in bilateral lower extremities. Sensation to pain, temperature, and position sense is absent in the buttocks, perineum, and lower extremities. Ankle clonus is present. Digital rectal examination is unremarkable. An x-ray of the spine shows multiple sclerotic lesions in the thoracic and lumbar vertebrae. Further evaluation of this patient is most likely to show which of the following?", "answer": "Elevated prostate-specific antigen", "options": {"A": "Left testicular mass", "B": "Irregular, asymmetric mole", "C": "Enlarged left thyroid lobe", "D": "Bence Jones protein in the urine", "E": "Elevated prostate-specific antigen"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 51-year-old African American man with a history of poorly controlled hypertension presents to the emergency room with blurry vision and dyspnea. He reports rapid-onset blurred vision and difficulty breathing 4 hours prior to presentation. He takes lisinopril, hydrochlorothiazide, and spironolactone but has a history of poor medication compliance. He has a 50 pack-year smoking history and drinks 4-6 shots of vodka per day. His temperature is 99.2°F (37.3°C), blood pressure is 195/115 mmHg, pulse is 85/min, and respirations are 20/min. On exam, he is ill-appearing and pale. He is intermittently responsive and oriented to person but not place or time. Fundoscopic examination reveals swelling of the optic disc with blurred margins. A biopsy of this patient’s kidney would most likely reveal which of the following?", "answer": "Concentrically thickened arteriolar tunica media with abundant nuclei", "options": {"A": "Anuclear arteriolar thickening", "B": "Calcific deposits in the arterial media without luminal narrowing", "C": "Concentrically thickened arteriolar tunica media with abundant nuclei", "D": "Endothelial proliferation and luminal narrowing with a chronic inflammatory infiltrate", "E": "Fibrous atheromatous plaques in the arteriolar intima"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A pharmaceutical company is studying the effect of a novel compound that they have discovered to treat osteoporosis. They perform a randomized controlled clinical trial to study if this compound has an effect on the incidence of hip fractures among osteoporotic patients. They find that there is no statistical difference between the experimental and control groups so they do not pursue the compound further. Two years later, a second team tests the same compound and finds that the compound is effective, and follow up studies confirm that the compound has a statistically significant effect on fracture risk. Which of the following most likely describes what occurred in the first study?", "answer": "Type II error", "options": {"A": "Design bias", "B": "Selection bias", "C": "Type I error", "D": "Type II error", "E": "Type III error"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old woman comes to the physician because of constipation, loss of appetite, and increased urinary frequency for the past 8 weeks. She has a history of hypertension and underwent mastectomy for breast cancer 9 months ago. Her sister has hyperthyroidism and her mother died of complications from breast cancer at the age of 52 years. She does not smoke or drink alcohol. Current medications include chlorthalidone. Her temperature is 36.2°C (97.2°F), pulse is 102/min, and blood pressure is 142/88 mm Hg. Physical examination shows dry mucous membranes. Abdominal examination shows mild, diffuse abdominal tenderness to palpation with decreased bowel sounds. Her serum creatinine concentration is 1.2 mg/dL and serum calcium concentration is 12 mg/dL. Serum parathyroid hormone levels are decreased. Which of the following is the most appropriate long-term pharmacotherapy?", "answer": "Zoledronic acid", "options": {"A": "Magnesium oxide", "B": "Denosumab", "C": "Furosemide", "D": "Zoledronic acid", "E": "Prednisone\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 61-year-old man is brought to the emergency department because of a 2-day history of fever, chills, and headache. He frequently has headaches, for which he takes aspirin, but says that this headache is more intense. His wife claims that he has also not been responding right away to her. He has a 20-year history of hypertension and poorly controlled type 2 diabetes mellitus. His current medications include metformin and lisinopril. He has received all recommended childhood vaccines. His temperature is 39°C (102.2F°), pulse is 100/min, and blood pressure is 150/80 mm Hg. He is lethargic but oriented to person, place, and time. Examination shows severe neck rigidity with limited active and passive range of motion. Blood cultures are obtained and a lumbar puncture is performed. Which of the following is the most likely causal organism?", "answer": "Streptococcus pneumoniae", "options": {"A": "Streptococcus agalactiae", "B": "Staphylococcus aureus", "C": "Neisseria meningitidis", "D": "Streptococcus pneumoniae", "E": "Escherichia coli"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old female comes to the ED complaining of epigastric pain and intractable nausea and vomiting for the last 24 hours. Her vitals are as follows: Temperature 38.1 C, HR 97 beats/minute, BP 90/63 mm Hg, RR 12 breaths/minute. Arterial blood gas and labs are drawn. Which of the following sets of lab values is consistent with her presentation?", "answer": "pH 7.51, PaCO2 50 , serum chloride 81 mEq/L, serum bicarbonate 38 mEq/L", "options": {"A": "pH 7.39, PaCO2 37 , serum chloride 102 mEq/L, serum bicarbonate 27 mEq/L", "B": "pH 7.36, PaCO2 75 , serum chloride 119 mEq/L, serum bicarbonate 42 mEq/L", "C": "pH 7.46, PaCO2 26 , serum chloride 102 mEq/L, serum bicarbonate 16 mEq/L", "D": "pH 7.51, PaCO2 50 , serum chloride 81 mEq/L, serum bicarbonate 38 mEq/L", "E": "pH 7.31, PaCO2 30 , serum chloride 92 mEq/L, serum bicarbonate 15 mEq/L"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old man comes to the physician because of worsening shortness of breath and nocturnal cough for the past 2 weeks. On two occasions, his cough was bloody. He had a heart condition as a child that was treated with antibiotics. He emigrated to the US from Kazakhstan 15 years ago. Pulmonary examination shows crackles at both lung bases. Cardiac examination is shown. Which of the following is the most likely diagnosis?", "answer": "Mitral valve stenosis", "options": {"A": "Aortic valve regurgitation", "B": "Mitral valve prolapse", "C": "Mitral valve stenosis", "D": "Mitral valve regurgitation", "E": "Tricuspid valve stenosis\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman comes to the emergency department because of a 12-hour history of a severe headache. She does not smoke or use illicit drugs. Her blood pressure at admission is 180/125 mm Hg. Physical examination shows a bruit in the epigastric region. Fundoscopy shows bilateral optic disc swelling. Which of the following investigations is most likely to confirm the diagnosis?", "answer": "CT angiography", "options": {"A": "Urinary catecholamine metabolites", "B": "Echocardiography", "C": "Serum 17-hydroxyprogesterone level", "D": "Oral sodium loading test", "E": "CT angiography"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A grant reviewer at the National Institutes of Health is determining which of two studies investigating the effects of gastric bypass surgery on fasting blood sugar to fund. Study A is spearheaded by a world renowned surgeon, is a multi-center study planning to enroll 50 patients at each of 5 different sites, and is single-blinded. Study B plans to enroll 300 patients from a single site and will be double-blinded by virtue of a sham surgery for the control group. The studies both plan to use a t-test, and they both report identical expected treatment effect sizes and variance. If the reviewer were interested only in which trial has the higher power, which proposal should he fund?", "answer": "Study B, because it has a larger sample size", "options": {"A": "Study A, because it has a superior surgeon", "B": "Study A, because it is a multi-center trial", "C": "Study B, because it has a larger sample size", "D": "Study B, because it is double blinded", "E": "Both studies have the same power"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old woman presents to the physician because of facial flushing and weakness for 3 months, abdominal discomfort and bloating for 6 months, and profuse watery diarrhea for 1 year. She reports that her diarrhea was episodic initially, but it has been continuous for the past 3 months. The frequency ranges from 10 to 12 bowel movements per day, and the diarrhea persists even if she is fasting. She describes the stools as odorless, watery in consistency, and tea-colored, without blood or mucus. She has not been diagnosed with any specific medical conditions, and there is no history of substance use. Her temperature is 36.9°C (98.4°F), heart rate is 88/min, respiratory rate is 18/min, and blood pressure is 110/74 mm Hg. Her physical exam shows decreased skin turgor, and the abdominal exam does not reveal any significant abnormality. Laboratory studies show:\nSerum glucose 216 mg/dL (12.0 mmol/L)\nSerum sodium 142 mEq/L (142 mmol/L)\nSerum potassium 3.1 mEq/L (3.1 mmol/L)\nSerum chloride 100 mEq/L (100 mmol/L)\nSerum calcium 11.1 mg/dL (2.77 mmol/L)\nHer 24-hour stool volume is 4 liters. Which of the following tests is most likely to yield an accurate diagnosis?", "answer": "Plasma vasoactive intestinal peptide", "options": {"A": "Urinary 5-hydroxyindoleacetic acid excretion", "B": "Plasma gastrin level", "C": "Plasma vasoactive intestinal peptide", "D": "Plasma glucagon level", "E": "Plasma somatostatin level"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to the physician by his parents because of a 4-day history of arthralgias, abdominal pain, and lesions on his arms and legs. Ten days ago, he had an upper respiratory tract infection. A photograph of one of his legs is shown. Further evaluation is most likely to show which of the following?", "answer": "Hematuria", "options": {"A": "Genital ulcers", "B": "Hematuria", "C": "Tick bite", "D": "Conjunctivitis", "E": "Thrombocytopenia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 61-year-old man comes to the physician because of a 3-month history of intermittent fever, easy fatiguability, and a 4.4-kg (9.7-lb) weight loss. Physical examination shows conjunctival pallor. The spleen is palpated 5 cm below the left costal margin. Laboratory studies show a leukocyte count of 75,300/mm3 with increased basophils, a platelet count of 455,000/mm3, and a decreased leukocyte alkaline phosphatase score. A peripheral blood smear shows increased numbers of promyelocytes, myelocytes, and metamyelocytes. Which of the following is the most likely diagnosis?", "answer": "Chronic myeloid leukemia", "options": {"A": "Leukemoid reaction", "B": "Chronic lymphocytic leukemia", "C": "Essential thrombocythemia", "D": "Chronic myeloid leukemia", "E": "Acute promyelocytic leukemia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old woman presents to the emergency department with progressive nausea and vomiting. She reports that approximately one day prior to presentation she experienced abdominal discomfort that subsequently worsened to severe nausea, vomiting, and two episodes of watery diarrhea. She recently noticed that her vision has become blurry along with mild alterations in color perception. Medical history is significant for congestive heart failure with a low ejection fraction. She cannot recall which medications she is currently taking but believes she is taking them as prescribed. Which of the following is a characteristic of the likely offending drug that led to this patient’s clinical presentation?", "answer": "Ratio of toxic dose to effective dose close to 1", "options": {"A": "High potency", "B": "Low potency", "C": "Ratio of toxic dose to effective dose much greater than 1", "D": "Ratio of toxic dose to effective dose close to 1", "E": "Low bioavailability"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old man who lives in a beach house in Florida visits his twin brother who lives in the Rocky Mountains. They are out hiking and the visitor struggles to keep up with his brother. Which of the following adaptations is most likely present in the mountain-dwelling brother relative to his twin?", "answer": "Decreased oxygen binding ability of hemoglobin", "options": {"A": "Decreased mean corpuscular hemoglobin concentration", "B": "Decreased red blood cell 2,3-diphosphoglycerate", "C": "Decreased oxygen binding ability of hemoglobin", "D": "Decreased pulmonary vascular resistance", "E": "Decreased renal erythropoietin production"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old G1P0000 presents to her obstetrician’s office for a routine prenatal visit at 32 weeks gestation. At this visit, she feels well and has no complaints. Her pregnancy has been uncomplicated, aside from her Rh negative status, for which she received Rhogam at 28 weeks gestation. The patient has a past medical history of mild intermittent asthma and migraine headaches. She currently uses her albuterol inhaler once a week and takes a prenatal vitamin. Her temperature is 98.6°F (37.0°C), pulse is 70/min, blood pressure is 117/68 mmHg, and respirations are 13/min. Cardiopulmonary exam is unremarkable, and abdominal exam reveals a gravid uterus with fundal height at 30 centimeters. Bedside ultrasound reveals that the fetus is in transverse lie. The patient states that she prefers to have a vaginal delivery. Which of the following is the best next step in management?", "answer": "Expectant management", "options": {"A": "Expectant management", "B": "Weekly ultrasound", "C": "External cephalic version", "D": "Internal cephalic version", "E": "Caesarean section at 38 weeks"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 54-year-old man with a past medical history significant for hypertension, type 2 diabetes, and chronic obstructive pulmonary disease presents with complaints of nausea and abdominal pain for the past month. The pain is located in the epigastric region and is described as “burning” in quality, often following food intake. The patient denies any changes in bowel movements, fever, or significant weight loss. Medications include metformin, lisinopril, hydrochlorothiazide, albuterol inhaler, and fluconazole for a recent fungal infection. Physical examination was unremarkable except for a mildly distended abdomen that is diffusely tender to palpation and decreased sensation at lower extremities bilaterally. A medication was started for the symptoms. Two days later, the patient reports heart palpitations. An EKG is shown below. Which of the following is the medication most likely prescribed?", "answer": "Erythromycin", "options": {"A": "Aspirin", "B": "Erythromycin", "C": "Metformin", "D": "Omeprazole", "E": "Ranitidine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying the affinity of hemoglobin for oxygen in different clinical settings. An illustration of an oxygen-hemoglobin dissociation curve is shown. Curve A shows the test results of one of the research participants and curve B shows a normal oxygen-hemoglobin dissociation curve. Which of the following is most likely present in this research participant?", "answer": "Polycythemia", "options": {"A": "Temperature of 39.1°C (102.4°F)", "B": "Sickled red blood cells", "C": "Neutrophilia", "D": "Serum pH of 7.1", "E": "Polycythemia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old obese woman presents with a severe right-sided frontotemporal headache that started 2 days ago. There is no improvement with over-the-counter pain medications. Yesterday, the pain was so intense that she stayed in bed all day in a dark, quiet room instead of going to work. This morning she decided to come in after an episode of vomiting. She says she has experienced 5–6 similar types of headaches each lasting 12–24 hours over the last 6 months but never this severe. She denies any seizures, visual disturbances, meningismus, sick contacts or focal neurologic deficits. Her past medical history is significant for moderate persistent asthma, which is managed with ipratropium bromide and an albuterol inhaler. She is currently sexually active with 2 men, uses condoms consistently, and regularly takes estrogen-containing oral contraceptive pills (OCPs). Her vital signs include: blood pressure 122/84 mm Hg, pulse 86/min, respiratory rate 19/min, and blood oxygen saturation (SpO2) 98% on room air. Physical examination, including a complete neurologic exam, is unremarkable. A magnetic resonance image (MRI) of the brain appears normal. Which of the following is the best prophylactic treatment for this patient’s most likely condition?", "answer": "Amitriptyline", "options": {"A": "Sumatriptan", "B": "Methysergide", "C": "Gabapentin", "D": "Amitriptyline", "E": "Ibuprofen"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "In a community of 5,000 people, 40 people from 40 different households develop an infection with a new strain of influenza virus with an incubation period of 7 days. The total number of people in these households is 150. Ten days later, 90 new cases of the same disease are reported from these same households. Twenty-five more cases are reported from these households after a month. The total number of cases reported after a month from this community is 1,024. What is the secondary attack rate for this infection?", "answer": "(90/110) × 100", "options": {"A": "(115/150) × 100", "B": "(115/1024) × 100", "C": "(90/110) × 100", "D": "(90/150) × 100", "E": "(90/5000) × 100"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 22-year-old woman is brought to the emergency department by campus police for bizarre behavior. She was arrested while trying to break into her university's supercomputer center and was found crying and claiming she needs access to the high-powered processors immediately. Her boyfriend arrived at the hospital and reports that, over the past week, she has been staying up all night working on ‘various projects’. A review of her electronic medical record reveals that she was seen at student health 1 week ago for low energy and depressed mood, for which treatment was started. In the emergency department, she continues to appear agitated, pacing around the room and scolding staff for stopping her from her important work. Her speech is pressured, but she exhibits no evidence of visual or auditory hallucinations. The physical exam is otherwise unremarkable. Which of the following medications most likely precipitated this patient’s event?", "answer": "Sertraline", "options": {"A": "Alprazolam", "B": "Haloperidol", "C": "Lithium", "D": "Sertraline", "E": "Valproate"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "You would like to conduct a study investigating potential risk factors that predispose patients to develop cirrhosis. Using a registry of admitted patients over the last 10 years at your local hospital, you isolate all patients who have been diagnosed with cirrhosis. Subsequently, you contact this group of patients, asking them to complete a survey assessing their prior exposure to alcohol use, intravenous drug abuse, blood transfusions, personal history of cancer, and other medical comorbidities. An identical survey is given to an equal number of patients in the registry who do not carry a prior diagnosis of cirrhosis. Which of the following best describes the type of study you are attempting to conduct?", "answer": "Case-control study", "options": {"A": "Cohort study", "B": "Meta-analysis", "C": "Case-control study", "D": "Cross-sectional study", "E": "Randomized controlled trial"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 18-year-old female presents to general medical clinic with the report of a rape on her college campus. The patient was visiting a local fraternity, and after having a few drinks, awakened to find another student having intercourse with her. Aside from the risk of unintended pregnancy and sexually transmitted infections, this patient is also at higher risk of developing which of the following?", "answer": "Suicidality", "options": {"A": "Attention Deficit Hyperactivity Disorder", "B": "Bipolar Disorder", "C": "Suicidality", "D": "Schizoaffective Disorder", "E": "Schizophrenia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old man complains of ascending weakness, palpitations, and abdominal pain. He has a history of hypertension, type II diabetes mellitus, diabetic retinopathy, and end-stage renal disease requiring dialysis. He denies any recent infection. Physical examination is notable for decreased motor strength in both his upper and lower extremities, intact cranial nerves, as well as decreased bowel sounds. On further questioning, the patient shares that he has been depressed, as he feels he may not be able to see his grandchildren grow due to his complicated medical course. This caused him to miss two of his dialysis appointments. Which of the following will mostly likely be found on electrocardiography?", "answer": "Peaked T-waves and shortened QT interval", "options": {"A": "Progressive PR prolongation, followed by a 'drop' in QRS", "B": "S wave in lead I, Q wave in lead III, and inverted T wave in lead III", "C": "ST-segment elevation in leads II, III, and aVF", "D": "Peaked T-waves and shortened QT interval", "E": "Diffuse PR segment depression and ST-segment deviations"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "After learning in a lecture that cesarean section rates vary from < 0.5% to over 30% across countries, a medical student wants to investigate if national cesarean section rates correlate with national maternal mortality rates worldwide. For his investigation, the student obtains population data from an international registry that contains tabulated cesarean section rates and maternal mortality rates from the last 10 years for a total of 119 countries. Which of the following best describes this study design?", "answer": "Ecological study", "options": {"A": "Case series", "B": "Meta-analysis", "C": "Retrospective cohort study", "D": "Ecological study", "E": "Prospective cohort study\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old woman presents to the fertility clinic with her husband for infertility workup. The patient reports that they have been having unprotected intercourse for 14 months without any successful pregnancy. She is G1P1, with 1 child from a previous marriage. Her menstrual cycle is regular and without pain. Physical and pelvic examinations are unremarkable. The husband denies erectile dysfunction, decrease in libido, or other concerns. A physical examination of the husband demonstrates tall long extremities and bilateral hard nodules behind the areola. What abnormality would you most likely find in the husband?", "answer": "Elevated aromatase levels", "options": {"A": "Decreased luteinizing hormone (LH) levels", "B": "Defective fibrillin", "C": "Elevated aromatase levels", "D": "Elevated homocysteine levels", "E": "Elevated testosterone levels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man comes to the physician because of a 10-day history of episodic retrosternal pain, shortness of breath, and palpitations. The episodes occur when he climbs stairs or tries to walk briskly on his treadmill. The symptoms resolve when he stops walking. The previous evening he felt dizzy and weak during such an episode. He also reports that he had a cold 2 weeks ago. He was diagnosed with type 2 diabetes mellitus four years ago but is otherwise healthy. His only medication is glyburide. He appears well. His pulse is 62/min and is weak, respirations are 20/min, and blood pressure is 134/90 mmHg. Cardiovascular examination shows a late systolic ejection murmur that is best heard in the second right intercostal space. The lungs are clear to auscultation. Which of the following mechanisms is the most likely cause of this patient's current condition?", "answer": "Increased left ventricular oxygen demand", "options": {"A": "Increased left ventricular oxygen demand", "B": "Lymphocytic infiltration of the myocardium", "C": "Critical transmural hypoperfusion of the myocardium", "D": "Catecholamine-induced transient regional systolic dysfunction", "E": "Increased release of endogenous insulin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old male is rushed to the emergency department (ED) for what he believes is his second myocardial infarction (MI). His medical history is significant for severe chronic obstructive pulmonary disease (COPD) and a prior MI at the age of 58. After receiving aspirin, morphine, and face mask oxygen in the field, the patient arrives to the ED tachycardic (105 bpm), diaphoretic, and normotensive (126/86). A 12 lead electrocardiogram shows ST-elevation in I, aVL, and V5-V6. The attending physician suspects a lateral wall infarction. Which of following beta-blockers should be given to this patient and why?", "answer": "Metoprolol, because it is a selective ß1 > ß2 blocker", "options": {"A": "Propranolol, because it is a non-selective ß-blocker", "B": "Metoprolol, because it is a selective ß1 > ß2 blocker", "C": "Atenolol, because it is a selective ß2 > ß1 blocker", "D": "Labetalol, because it is a selective ß1 > ß2 blocker", "E": "Nadolol, because it is a selective ß1 > ß2 blocker"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old woman presents to a primary care clinic for a physical evaluation. She works as a software engineer, travels frequently, is married with 2 kids, and drinks alcohol occasionally. She does not exercise regularly. She currently does not take any medications except for occasional ibuprofen or acetaminophen. She is currently undergoing menopause. Her initial vital signs reveal that her blood pressure is 140/95 mmHg and heart rate is 75/min. She weighs 65 kg (143 lb) and is 160 cm (63 in) tall. Her physical exam is unremarkable. A repeat measurement of her blood pressure is the same as before. Among various laboratory tests for hypertension evaluation, the physician requests fasting glucose and hemoglobin A1c levels. Which of the following is the greatest risk factor for type 2 diabetes mellitus?", "answer": "Body mass index", "options": {"A": "Age", "B": "Body mass index", "C": "Hypertension", "D": "Menopause", "E": "Occupation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 8-month-old boy is brought to the emergency department by his mother and father due to decreasing activity and excessive sleepiness. The patient was born at full-term in the hospital with no complications. The patient's parents appear incredibly worried as their son has had no medical issues in the past. They show you videos of the child happily playing with his parents the day before. The patient’s mother states that the patient hit his head while crawling this morning and since then has been difficult to arouse. His mother is worried because she thinks he had a fever earlier in the day and he was clutching his head and neck in pain. Physical examination shows a barely arousable boy with a large, full anterior fontanelle. The boy grimaces on palpation of his chest, and a radiograph show posterior rib fractures. Retinal examination shows bilateral retinal hemorrhages. Which of the following is the most likely cause for this patient’s presentation?", "answer": "Child abuse", "options": {"A": "Child abuse", "B": "Unintentional head injury", "C": "Vitamin K deficiency", "D": "Osteogenesis imperfecta", "E": "Bacterial meningitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman comes to the physician because of a 2-month history of generalized itching and worsening fatigue. There is no personal or family history of serious illness. She takes eye drops for dry eyes. She occasionally takes acetaminophen for recurrent headaches. She drinks one alcoholic beverage daily. Vital signs are within normal limits. Examination shows jaundice and a nontender abdomen. The liver is palpated 3 cm below the right costal margin and the spleen is palpated 2 cm below the left costal margin. Laboratory studies show:\nHemoglobin 15.3 g/dL\nLeukocyte count 8,400/mm3\nProthrombin time 13 seconds\nSerum\nBilirubin\nTotal 3.5 mg/dL\nDirect 2.4 mg/dL\nAlkaline phosphatase 396 U/L\nAspartate aminotransferase (AST, GOT) 79 U/L\nAlanine aminotransferase (ALT, GPT) 73 U/L\nA liver biopsy specimen shows inflammation and destruction of small- and medium-sized intrahepatic bile ducts. Magnetic resonance cholangiopancreatography (MRCP) shows multiple small stones within the gallbladder and a normal appearance of extrahepatic bile ducts. Which of the following is the most appropriate next step in management?\"", "answer": "Dual-energy x-ray absorptiometry", "options": {"A": "Extracorporeal shock wave lithotripsy", "B": "Dual-energy x-ray absorptiometry", "C": "Administer N-acetylcysteine", "D": "Serum electrophoresis", "E": "Chest x-ray"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 75-year-old man presents to the physician with difficulty breathing for the last 2 months. He denies any cough, fever, or chest pain. His past medical history is significant for hypertension for which he takes chlorothiazide. He has worked in the construction industry, applying insulation to roofs for over 20 years. He denies smoking, drinking, and illicit drug use. His pulse rate is 74/min, respiratory rate is 14/min, blood pressure is 130/76 mm Hg, and temperature is 36.8°C (98.2°F). Physical examination reveals some end-inspiratory crackles at the lung bases. No other examination findings are significant. The lung inflation curve is obtained for the patient and is shown in the image. Which of the following most likely accounts for this patient’s symptoms?", "answer": "Pulmonary fibrosis", "options": {"A": "Normal aging", "B": "Alpha-1 antitrypsin deficiency", "C": "Asthma", "D": "Idiopathic pulmonary hypertension", "E": "Pulmonary fibrosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 14-year-old boy presents to an urgent care clinic complaining of a runny nose that has lasted for a few weeks. He also reports sneezing attacks that last up to an hour, nasal obstruction, and generalized itching. He has similar episodes each year during the springtime that prevent him from going out with his friends or trying out for sports. His younger brother has a history of asthma. Which of the following diseases has a similar pathophysiology?", "answer": "Atopic dermatitis", "options": {"A": "Allergic contact dermatitis", "B": "Atopic dermatitis", "C": "Irritant contact dermatitis", "D": "Systemic lupus erythematosus", "E": "Dermatitis herpetiformis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old G2P1 undergoes labor induction at 40 weeks gestation. The estimated fetal weight was 3890 g. The pregnancy was complicated by gestational diabetes treated with insulin. The vital signs were as follows: blood pressure 125/80 mm Hg, heart rate 91/min, respiratory rate 21/min, and temperature 36.8℃ (98.2℉). The blood workup yields the following results:\nFasting glucose 92 mg/dL\nHbA1c  7.8%\nErythrocyte count 3.3 million/mm3\nHb 11.6 mg/dL\nHt 46%\nThrombocyte count 240,000/mm3\nSerum creatinine 0.71 mg/dL\nALT 12 IU/L\nAST 9 IU/L\nWhich of the following should be administered during labor?", "answer": "5% dextrose", "options": {"A": "5% dextrose", "B": "Intravenous regular insulin", "C": "25% magnesium sulphate", "D": "Erythrocyte mass", "E": "Subcutaneous insulin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 33-year-old man is brought to the emergency department by his partner for 24 hours of fever, severe headache, and neck stiffness. His companion also comments that he has been vomiting several times in the past 8 hours and looks confused. His personal medical history is unremarkable. Upon examination, his blood pressure is 125/82 mm Hg, heart rate 110/mine, and temperature is 38.9 C (102F). There is no rash or any other skin lesions, his lung sounds are clear and symmetrical. There is nuchal rigidity, jolt accentuation of a headache, and photophobia. A lumbar puncture is taken, and cerebrospinal fluid is sent for analysis and a Gram stain (shown in the picture). The patient is put on empirical antimicrobial therapy with ceftriaxone and vancomycin. According to the clinical manifestations and Gram stain, which of the following should be considered in the management of this case?", "answer": "Prophylaxis with rifampin for close contacts", "options": {"A": "Addition of ampicillin", "B": "Prophylaxis with rifampin for close contacts", "C": "Switch to meropenem", "D": "Initiation of amphotericin", "E": "Initiation rifampin, isoniazid, pyrazinamide, and ethambutol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old male presents to a clinic for routine follow-up. He was diagnosed with hepatitis B several months ago. He does not have any complaints about his health, except for poor appetite. The general physical examination is normal. The laboratory investigation reveals mildly elevated aminotransferases. Which of the following findings indicate that the patient has developed a chronic form of his viral infection?", "answer": "HbsAg +, Anti-HbsAg -, Anti-HbcAg IgM -, Anti-HbcAg IgG +, HbeAg +, Anti-HbeAg -", "options": {"A": "HbsAg -, Anti-HbsAg -, Anti-HbcAg IgM +, Anti-HbcAg IgG -, HbeAg -, Anti-HbeAg +", "B": "HbsAg +, Anti-HbsAg -, Anti-HbcAg IgM +, Anti-HbcAg IgG -, HbeAg +, Anti-HbeAg -", "C": "HbsAg +, Anti-HbsAg -, Anti-HbcAg IgM -, Anti-HbcAg IgG +, HbeAg +, Anti-HbeAg -", "D": "HbsAg -, Anti-HbsAg +, Anti-HbcAg IgM -, Anti-HbcAg IgG -, HbeAg -, Anti-HbeAg -", "E": "HbsAg -, Anti-HbsAg +, Anti-HbcAg IgM -, Anti-HbcAg IgG +, HbeAg -, Anti-HbeAg +"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old man comes to the physician with involuntary lip smacking and hand and leg movements for the past two weeks. The movements are causing him difficulty walking and functioning at work. He has bipolar disorder treated with fluphenazine. Three months ago, he was hospitalized because of a manic episode, and his dosage was adjusted. Since then, he has not experienced a depressed mood, increased energy, irritability, or a change in his eating or sleeping patterns. He does not have suicidal or homicidal ideation. His temperature is 37.2°C (99°F), pulse is 75/min, and blood pressure is 126/78 mmHg. Examination shows repetitive lip smacking and dance-like hand and leg movements. His speech is not pressured, and his affect is appropriate. He is switched from fluphenazine to risperidone and his symptoms improve. Which of the following mechanisms explains this patient's improvement?", "answer": "Weaker dopamine antagonism", "options": {"A": "Weaker acetylcholine antagonism", "B": "Weaker histamine antagonism", "C": "Weaker acetylcholine agonism", "D": "Weaker dopamine antagonism", "E": "Weaker histamine agonism"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old-woman presents to the emergency room with complaints of fever and abdominal pain. Her blood pressure is 130/74 mmHg, pulse is 98/min, temperature is 101.5°F (38.6°C), and respirations are 23/min. The patient reports that she had a laparoscopic cholecystectomy 4 days ago but has otherwise been healthy. She is visiting her family from Nebraska and just arrived this morning from a 12-hour drive. Physical examination revealed erythema and white discharge from abdominal incisions and tenderness upon palpations at the right upper quadrant. What is the most probable cause of the patient’s fever?", "answer": "Wound infection", "options": {"A": "Pulmonary atelectasis", "B": "Pulmonary embolism", "C": "Residual gallstones", "D": "Urinary tract infection", "E": "Wound infection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 16-year-old girl comes to the physician because she is worried about gaining weight. She reports that at least twice a week, she eats excessive amounts of food but feels ashamed about losing control soon after. She is very active in her high school's tennis team and goes running daily to lose weight. She has a history of cutting her forearms with the metal tab from a soda can. Her last menstrual period was 3 weeks ago. She is 165 cm (5 ft 5 in) tall and weighs 57 kg (125 lb); BMI is 21 kg/m2. Physical examination shows enlarged, firm parotid glands bilaterally. There are erosions of the enamel on the lingual surfaces of the teeth. Which of the following is the most likely diagnosis?", "answer": "Bulimia nervosa", "options": {"A": "Obsessive-compulsive disorder", "B": "Borderline personality disorder", "C": "Bulimia nervosa", "D": "Anorexia nervosa", "E": "Body dysmorphic disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 37-year-old woman presents to the emergency department with a chief complaint of severe pain in her face. She states that over the past week she has experienced episodic and intense pain in her face that comes on suddenly and resolves on its own. She states she feels the pain over her cheek and near her eye. The pain is so severe it causes her eyes to tear up, and she is very self conscious about the episodes. She fears going out in public as a result and sometimes feels her symptoms come on when she thinks about an episode occurring while in public. While she is waiting in the emergency room her symptoms resolve. The patient has a past medical history of diabetes, constipation, irritable bowel syndrome, and anxiety. She is well known to the emergency department for coming in with chief complaints that often do not have an organic etiology. Her temperature is 99.5°F (37.5°C), blood pressure is 177/108 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Cardiopulmonary and abdominal exams are within normal limits. Neurological exam reveals cranial nerves II-XII are grossly intact. The patient's pupils are equal and reactive to light. Pain is not elicited with palpation of the patient's face. Which of the following is the best initial step in management?", "answer": "Carbamazepine", "options": {"A": "Alprazolam", "B": "Carbamazepine", "C": "High flow oxygen", "D": "Ibuprofen", "E": "Regular outpatient follow up"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man with type 2 diabetes mellitus presents to his family physician for a follow-up appointment. He is currently using a 3-drug regimen consisting of metformin, sitagliptin, and glipizide. Despite this therapeutic regimen, his most recent hemoglobin A1c level is 8.1%. Which of the following is the next best step for this patient?", "answer": "Discontinue glipizide; initiate insulin glargine 10 units at bedtime", "options": {"A": "Discontinue glipizide; initiate insulin glargine 10 units at bedtime", "B": "Discontinue metformin; initiate basal-bolus insulin", "C": "Discontinue metformin; initiate insulin aspart at mealtimes", "D": "Discontinue sitagliptin; initiate basal-bolus insulin", "E": "Discontinue metformin; initiate insulin glargine 10 units at bedtime"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 35-year-old woman has been trying to conceive with her 37-year-old husband for the past 4 years. After repeated visits to a fertility clinic, she finally gets pregnant. Although she missed most of her antenatal visits, her pregnancy was uneventful. A baby girl is born at the 38th week of gestation with some abnormalities. She has a flat face with upward-slanting eyes and a short neck. The tongue seems to be protruding from a small mouth. She has poor muscle tone and excessive joint laxity. The pediatrician orders an analysis of the infant’s chromosomes, also known as a karyotype (see image). The infant is most likely to suffer from which of the following conditions in the future?", "answer": "Acute lymphoblastic leukemia", "options": {"A": "Acute lymphoblastic leukemia", "B": "Chronic myelogenous leukemia", "C": "Immotile cilia syndrome", "D": "Macroorchidism", "E": "Red blood cell sickling"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 64-year-old gentleman with hypertension is started on a new diuretic medication by his primary care physician because of poor blood pressure control on his previous regimen. Before starting, he is warned by his physician that the new medication may have side effects including hypokalemia and metabolic alkalosis. Furthermore it may cause alterations in his metabolites such as hyperglycemia, hyperlipidemia, hyperuricemia, and hypercalcemia. What is the mechanism of the class of diuretic most likely being recommended by the physician?", "answer": "NCC inhibitor in distal tubule", "options": {"A": "Osmotic diuresis", "B": "NKCC inhibitor in loop of Henle", "C": "NCC inhibitor in distal tubule", "D": "ENaC inhibitor in collecting duct", "E": "Aldosterone receptor inhibitor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 66-year-old man presents to the outpatient department complaining of a rash similar to the ones in the image. The skin lesions have been present for about 2 weeks. It is present in the buttocks and both inferior limbs. There is no association of skin lesions with exposure to sunlight or medication use. The patient also reports joint pain affecting the distal and proximal joints in both the upper and lower limbs. The joint pain has been present for about a week and seems to improve with Tylenol use. The patient is a retired armed force personnel with an extensive tour of overseas duty. He received blood transfusion following a career-ending injury about 30 years ago. He denies alcohol and tobacco use. He is currently in a monogamous relationship with his wife for 40 years. His past medical history is significant for hypertension controlled on Enalapril. Physical examination shows mild pallor, multiple palpable purpuric lesions with occasional ulcerations bilaterally in the upper and lower limbs. Pulse rate is 88/min and blood pressure is 128/82 mm Hg. Laboratory test findings are:\nHIV I and II antibodies negative\nRheumatoid factor positive\nHepatitis C antigen positive\nHepatitis B surface antigen positive\nHepatitis B antibody positive\nAnti-neutrophil antibody positive\nHematocrit 38%\nWhich of the following mechanisms is most likely responsible for his clinical presentation?", "answer": "Virus-induced clonal expansion of autoreactive B lymphocytes", "options": {"A": "Cyto-proliferative effect of HCV on hepatocytes", "B": "Excessive uroporphyrinogen caused by HCV induced decarboxylase deficiency", "C": "Defective hepatic removal of IgA caused by chronic HCV", "D": "Monoclonal expansion of IgM caused by benign neoplasia", "E": "Virus-induced clonal expansion of autoreactive B lymphocytes"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old man is brought to the emergency department because of fever, progressive weakness, and cough for the past five days. He experienced a similar episode 2 months ago, for which he was hospitalized for 10 days while visiting his son in Russia. He states that he has never fully recovered from that episode. He felt much better after being treated with antibiotics, but he still coughs often during meals. He sometimes also coughs up undigested food after eating. For the last 5 days, his coughing has become more frequent and productive of yellowish-green sputum. He takes hydrochlorothiazide for hypertension and pantoprazole for the retrosternal discomfort that he often experiences while eating. He has smoked half a pack of cigarettes daily for the last 30 years and drinks one shot of vodka every day. The patient appears thin. His temperature is 40.1°C (104.2°F), pulse is 118/min, respirations are 22/min, and blood pressure is 125/90 mm Hg. Auscultation of the lungs shows right basal crackles. There is dullness on percussion at the right lung base. The remainder of the physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 15.4 g/dL\nLeukocyte count 17,000/mm3\nPlatelet count 350,000/mm3\nNa+ 139 mEq/L\nK+\n4.6 mEq/L\nCl- 102 mEq/L\nHCO3- 25 mEq/L\nUrea Nitrogen 16 mg/dL\nCreatinine 1.3 mg/dL\nAn x-ray of the chest shows a right lower lobe infiltrate. Which of the following is the most likely explanation for this patient's symptoms?\"", "answer": "Outpouching of the hypopharynx\n\"", "options": {"A": "Weak tone of the lower esophageal sphincter", "B": "Formation of a tissue cavity containing necrotic debris", "C": "Uncoordinated contractions of the esophagus", "D": "Unrestricted growth of pneumocytes with invasion of the surrounding tissue", "E": "Outpouching of the hypopharynx\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Benzodiazepines are clinically useful because of their inhibitory effects on the central nervous system. Which of the following correctly pairs the site of action of benzodiazepines with the molecular mechanism by which a they exerts their effects?", "answer": "GABA-A receptors; increasing the frequency of activation of a chloride ion channel", "options": {"A": "GABA-A receptors; blocking action of GABA", "B": "GABA-B receptors; activating potassium channels", "C": "GABA-B receptors; activating a G-protein coupled receptor", "D": "GABA-A receptors; increasing the duration of activation of a chloride ion channel", "E": "GABA-A receptors; increasing the frequency of activation of a chloride ion channel"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 57-year-old male with diabetes mellitus type II presents for a routine check-up. His blood glucose levels have been inconsistently controlled with medications and diet since his diagnosis 3 years ago. At this current visit, urinalysis demonstrates albumin levels of 250 mg/day. All prior urinalyses have shown albumin levels below 20 mg/day. At this point in the progression of the patient’s disease, which of the following is the most likely finding seen on kidney biopsy?", "answer": "Glomerular basement membrane thickening and mesangial expansion", "options": {"A": "Normal kidney biopsy, no pathological finding is evident at this time", "B": "Glomerular hypertrophy with slight glomerular basement membrane thickening", "C": "Glomerular basement membrane thickening and mesangial expansion", "D": "Kimmelstiel-Wilson nodules and tubulointerstitial fibrosis", "E": "Significant global glomerulosclerosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 26-year-old man comes to the physician for evaluation of fatigue, facial rash, hair loss, and tingling of his hands and feet. He has followed a vegetarian diet for the past 3 years and has eaten 8 raw egg whites daily for the past year in preparation for a bodybuilding competition. Physical examination shows conjunctival injections and a scaly, erythematous rash around the eyes and mouth. Laboratory studies show decreased activity of propionyl-coenzyme A carboxylase in peripheral blood lymphocytes. Which of the following substances is most likely to be decreased in this patient?", "answer": "Oxaloacetate", "options": {"A": "Cystathionine", "B": "Ribulose-5-phosphate", "C": "Adenine", "D": "Lactate", "E": "Oxaloacetate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A full-term and healthy infant girl presents to the office for a newborn visit. The baby was born at 40 weeks to a 35-year-old G2P1 mother via cesarean section for breech presentation. She had an unremarkable delivery and hospital course, but family history is significant for a sister with developmental dysplasia of the hip (DDH). A physical exam is normal. During a discussion with the mother about the possibility of screening imaging for DDH she becomes very anxious and would like something done as soon as possible. What would be the imaging of choice in this scenario?", "answer": "Hip ultrasound at 6 weeks of age", "options": {"A": "Hip MRI at 6 weeks of age", "B": "Hip ultrasound at 6 weeks of age", "C": "Hip ultrasound within the next week", "D": "Hip radiograph at 6 weeks of age", "E": "Hip radiograph at 5 months of age"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old man comes to the emergency department for evaluation of burning with urination and purulent urethral discharge for the past 3 days. He is sexually active with multiple female partners. Several months ago he was diagnosed with urethritis caused by gram-negative diplococci and received antibiotic treatment with complete resolution of his symptoms. A Gram stain of the patient's urethral discharge shows gram-negative intracellular diplococci. Which of the following properties of the infecting organism most contributed to the pathogenesis of this patient's recurrent infection?", "answer": "Variation of expressed pilus proteins", "options": {"A": "Expression of beta-lactamase genes", "B": "Synthesis of capsular polysaccharides", "C": "Absence of immunogenic proteins", "D": "Production of enzymes that hydrolyze urea", "E": "Variation of expressed pilus proteins"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 54-year-old woman comes to the emergency department because of a 5-hour history of diffuse, severe abdominal pain, nausea, and vomiting. She reports that there is no blood or bile in the vomitus. Two weeks ago, she started having mild aching epigastric pain, which improved with eating. Since then, she has gained 1.4 kg (3 lb). She has a 2-year history of osteoarthritis of both knees, for which she takes ibuprofen. She drinks 1–2 glasses of wine daily. She is lying supine with her knees drawn up and avoids any movement. Her temperature is 38.5°C (101.3°F), pulse is 112/min, respirations are 20/min, and blood pressure is 115/70 mm Hg. Physical examination shows abdominal tenderness and guarding; bowel sounds are decreased. An x-ray of the chest is shown. Which of the following is the most likely cause of this patient's current symptoms?", "answer": "Perforated peptic ulcer", "options": {"A": "Perforated peptic ulcer", "B": "Acute pancreatitis", "C": "Acute mesenteric ischemia", "D": "Gastroesophageal reflux disease", "E": "Cholecystolithiasis\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old-woman presents to an urgent care clinic with right upper quadrant pain for the past few hours. She admits to having similar episodes of pain in the past but milder than today. Past medical history is insignificant. She took an antacid, but it did not help. Her temperature is 37°C (98.6°F ), respirations are 16/min, pulse is 78/min, and blood pressure is 122/98 mm Hg. Physical examination is normal, and she says that her pain has subsided. The urgent care provider suspects she has cholecystitis, so she undergoes a limited abdominal ultrasound to confirm it. However, no evidence of cholecystitis is seen with ultrasound, but adenomyomatosis of the gallbladder is incidentally noted. The patient has no clinical features suspicious for malignancy. What is the next best step in the management of this patient?", "answer": "No further treatment required", "options": {"A": "Cholecystectomy", "B": "Barium swallow study", "C": "Endoscopic retrograde cholangiopancreatography", "D": "Magnetic resonance cholangiopancreatography", "E": "No further treatment required"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 67-year-old man presents to your office with a chief complaint of constipation and many other perturbing minor medical concerns. He reports tiring easily, which he attributes to old age and years of persistent pain in his back and ribs. A complete blood count shows low hemoglobin and elevated serum creatinine. A peripheral blood smear shows stacks of red blood cells among other findings, and serum electropheresis reveals an abnormal concentration of protein resulting in a spike. Which of the following additional findings would you expect to see in this patient?", "answer": "Bence-Jones proteins in the urine", "options": {"A": "Early satiety and splenomegaly", "B": "Smudge cells on peripheral smear", "C": "An elevated PSA and a nodular prostate", "D": "Bence-Jones proteins in the urine", "E": "No additional findings - normal aging explains symptoms"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 16-year-old girl presents with episodes of sharp pain in her left upper limb. She says her symptoms gradually onset a few months ago and have progressively worsened. She describes her pain as severe and feeling like “someone stabbing me in my arm and then the pain moves down to my hand”. She says the pain is worse after physical activity and improves with rest. She also says she has some vision problems in her left eye. The patient is afebrile, and her vital signs are within normal limits. On physical examination, there are no visible deformities in the shoulders or upper extremities. Palpation of her left upper limb reveals tenderness mainly near her neck. Mild left-sided ptosis is present. There is anisocoria of her left pupil which measures 1 mm smaller than the right. The right upper limb is normal. A plain radiograph and an MRI are ordered (shown in the image). Which of the following focal neurologic deficits would most likely be seen on the left hand of this patient?", "answer": "Numbness over her left little finger", "options": {"A": "Numbness over her left thumb", "B": "Crutch palsy", "C": "Numbness over her left index finger", "D": "Numbness over her left little finger", "E": "Numbness over the thenar area of her left hand"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man presents with worsening joint pain and stiffness. Past medical history is significant for rheumatoid arthritis, diagnosed 3 months ago and managed with celecoxib and methotrexate, and occasional gastric reflux, managed with omeprazole. His vitals are a pulse of 80/min, a respiratory rate of 16/min, and blood pressure of 122/80 mm Hg. On physical examination, the left wrist is swollen, stiff, and warm to touch, and the right wrist is red and warm. There is limited active and passive range of motion at the proximal interphalangeal and metacarpophalangeal joints of both hands. The remainder of the examination is unremarkable. A plain radiograph of the hands shows progressive degeneration of multiple joints. Another drug, etanercept, is added to help control progressive arthritis. Which of the following diagnostic tests should be ordered before starting this new medication in this patient?", "answer": "Tuberculosis screening", "options": {"A": "Tuberculosis screening", "B": "Antinuclear antibody (ANA) level", "C": "Endoscopy", "D": "Bleeding time", "E": "Malignancy screening"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 78-year-old male comes to the physician’s office for a routine check-up. He complains of increased lower extremity swelling, inability to climb the one flight of stairs in his home, and waking up in the middle of the night 2-3 times gasping for breath. He has had to increase the number of pillows on which he sleeps at night. These symptoms started 9 months ago and have been progressing. The doctor starts him on a medication regimen, one of which changes his Starling curve from A to B as shown in the Figure. Which of the following medications is most consistent with this mechanism of action?", "answer": "Digoxin", "options": {"A": "Metoprolol", "B": "Furosemide", "C": "Hydrochlorothiazide", "D": "Aspirin", "E": "Digoxin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old woman comes to the physician because of lower back pain that began suddenly 2 weeks ago after getting up from her chair. She has hypertension, chronic bilateral knee pain, and a history of breast cancer 15 years ago that was treated with lumpectomy. Her mother has rheumatoid arthritis. Medications include hydrochlorothiazide and acetaminophen. She appears well. Her vital signs are within normal limits. Physical examination shows tenderness to palpation of the lower spine. Both knees are enlarged and swollen. Neurologic examination shows sensorineural hearing impairment of the left ear. Her gamma-glutamyl transferase (GGT) is 30 U/L (N: 0–30 U/L), alkaline phosphatase (ALP) is 310 U/L, and serum calcium is 10.2 mg/dL. A spinal x-ray shows a fracture in the L4 vertebra. Which of the following is the most likely diagnosis?", "answer": "Paget disease of bone", "options": {"A": "Type 1 osteopetrosis", "B": "Primary biliary cholangitis", "C": "Rheumatoid arthritis", "D": "Paget disease of bone", "E": "Bone metastases"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy is brought in to his pediatrician by his mother because of several days of fever, irritability, and ear pain. His mother says that she was particularly concerned about his complaints of difficulty hearing and dizziness. Physical exam reveals a bulging tympanic membrane. As the pediatrician does the examination, she explains to the medical student accompanying her that the lining of the infected area is derived from the endodermal component of a certain embryological structure. The mesodermal component at the same level is most likely responsible for the development of which of the following structures?", "answer": "Mylohyoid muscle", "options": {"A": "Cricothyroid muscle", "B": "Mylohyoid muscle", "C": "Stylohyoid muscle", "D": "Stylopharyngeus muscle", "E": "Thyroarytenoid muscle"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman comes to the physician because of right-sided blurry vision and eye pain for 4 days. She has a 6-day history of low-grade fever, headache, and malaise. One year ago, she was diagnosed with Crohn disease. Her only medication is prednisone. Her temperature is 38°C (100.4°F), pulse is 84/min, and blood pressure is 112/75 mm Hg. The right eyelid is erythematous and tender; there are multiple vesicles over the right forehead and the tip of the nose. Visual acuity is 20/20 in the left eye and 20/80 in the right eye. Extraocular movements are normal. The right eye shows conjunctival injection and reduced corneal sensitivity. Fluorescein staining shows a corneal lesion with a tree-like pattern. Which of the following is the most likely diagnosis?", "answer": "Herpes zoster keratitis", "options": {"A": "Pseudomonas keratitis", "B": "Anterior uveitis", "C": "Herpes zoster keratitis", "D": "Angle-closure glaucoma", "E": "Herpes simplex keratitis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A pathologist examines a tissue specimen in which cells are grouped together in acini with visible ducts between them. He finds a patch of pale cells with a rich blood supply among the highly basophilic and granular cells. A representative micrograph is shown in the image. Which statement is correct about these cells?", "answer": "There are several different types of cells within the patch that cannot be differentiated by light microscopy.", "options": {"A": "These cells should be separated from the basophils by a dense capsule.", "B": "These cells are often found to be damaged in acute pancreatitis with a subsequent increase in serum amylase levels.", "C": "Some of these cells undergo transformation and begin to secrete insulin to compensate for the loss of pancreatic beta cells.", "D": "There are several different types of cells within the patch that cannot be differentiated by light microscopy.", "E": "Some of these cells are capable of producing leptin, a hormone which regulates satiety."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old woman presents to the emergency department with prominent hypotension and tachycardia. On examination, she has a low central venous pressure and high cardiac output. Her temperature is 38.9°C (102.0°F). The physician suspects a bacterial infection with a gram-negative bacterium. Samples are sent to the lab. Meanwhile, high volumes of fluids were given, but the blood pressure did not improve. She was started on noradrenaline. At the biochemical level, a major reaction was induced as part of this patient’s presentation. Of the following vitamins, which one is related to the coenzyme that participates in this induced biochemical reaction?", "answer": "Vitamin B3 (niacin)", "options": {"A": "Vitamin B1 (thiamine)", "B": "Vitamin B2 (riboflavin)", "C": "Vitamin B3 (niacin)", "D": "Vitamin B5 (pantothenic acid)", "E": "Vitamin B6 (pyridoxal phosphate)"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A public health researcher is invited to participate in a government meeting on immunization policies. Other participants in the meeting include physicians, pediatricians, representatives of vaccine manufacturers, persons from the health ministry, etc. For a specific viral disease, there are 2 vaccines - one is a live attenuated vaccine (LAV) and the other is a subunit vaccine. Manufacturers of both the vaccines promote their own vaccines in the meeting. Non-medical people in the meeting ask the public health researcher to compare the 2 types of vaccines objectively. The public health researcher clearly explains the pros and cons of the 2 types of vaccines. Which of the following statements is most likely to have been made by the public health researcher in his presentation?", "answer": "LAV requires stricter requirements for cold chain maintenance as compared to a subunit vaccine", "options": {"A": "LAV has a less potential for immunization errors as compared to a subunit vaccine", "B": "LAV cannot cause symptomatic infection in a immunocompetent person and, therefore, is as safe as a subunit vaccine", "C": "LAV is equally safe as a subunit vaccine for administration to a pregnant woman", "D": "LAV requires stricter requirements for cold chain maintenance as compared to a subunit vaccine", "E": "LAV produces poorer immunological memory than a subunit vaccine as the later contains only specific immunogenic antigens"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old man presents to his primary care physician for a decline in his hearing that he noticed over the past week. The patient has a past medical history of hypertension and diabetes mellitus and was recently diagnosed with bladder cancer which is currently appropriately being treated. The patient is a hunter and often goes shooting in his spare time. His recent sick contacts include his grandson who is being treated with amoxicillin for ear pain. Physical exam is notable for decreased hearing bilaterally. The Weber test does not localize to either ear, and the Rinne test demonstrates air conduction is louder than bone conduction. Which of the following is the most likely etiology for this patient's hearing loss?", "answer": "Medication regimen", "options": {"A": "Medication regimen", "B": "Otitis externa", "C": "Otitis media", "D": "Otosclerosis", "E": "Presbycusis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old man is rushed to the emergency department by ambulance after being found on the floor gasping for air with severe shortness of breath by his partner. Past medical history is significant for congestive heart failure, hypertension, and hyperlipidemia. He normally takes chlorthalidone, atorvastatin, metoprolol, and valsartan, but he recently lost his job and insurance and has not been able to afford his medication in 2 months. Upon arrival at the hospital, his blood pressure is 85/50 mm Hg, heart rate is 110/min, respiratory rate is 24/min, oxygen saturation 90% on 100% oxygen, and temperature is 37.7°C (99.9°F). On physical exam, he appears obese and can only answer questions in short gasps as he struggles to breathe. His heart rate is tachycardic with a mildly irregular rhythm and auscultation of his lungs reveal crackles in the lower lobes, bilaterally. Which of the following physiologic changes is currently seen in this patient?", "answer": "↑ Plasma renin and angiotensin II activity, ↓ blood pressure, ↓ renal perfusion pressure, ↑ serum pH", "options": {"A": "↓ Plasma renin and angiotensin II activity, ↑ blood pressure, normal renal perfusion pressure, ↑ serum pH", "B": "↑ Plasma renin and angiotensin II activity, ↑ blood pressure, normal renal perfusion pressure, ↓ serum pH", "C": "Normal plasma renin and angiotensin II activity, ↓ blood pressure, ↓ renal perfusion pressure, ↓ serum pH", "D": "↑ Plasma renin and angiotensin II activity, ↓ blood pressure, ↓ renal perfusion pressure, ↑ serum pH", "E": "↑ Plasma renin and angiotensin II activity, ↑ blood pressure,↓ renal perfusion pressure, ↑ serum pH"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old man presents to the emergency room following a stab wound to the back. He was in a bar when he got into an argument with another man who proceeded to stab him slightly right of the midline of his back. He is otherwise healthy and does not take any medications. He has one previous admission to the hospital for a stab wound to the leg from another bar fight 2 years ago. His temperature is 99°F (37.2°C), blood pressure is 115/80 mmHg, pulse is 100/min, and pulse oximetry is 99% on room air. Cardiopulmonary and abdominal exams are unremarkable; however, he has an abnormal neurologic exam. If this wound entered his spinal cord but did not cross the midline, which of the following would most likely be seen in this patient?", "answer": "Ipsilateral flaccid paralysis at the level of the lesion", "options": {"A": "Ipsilateral loss of pain and temperature sensation below the lesion", "B": "Contralateral loss of tactile, vibration, and proprioception below the lesion", "C": "Contralateral spasticity below the level of the lesion", "D": "Ipsilateral flaccid paralysis at the level of the lesion", "E": "Contralateral loss of sensation at the level of the lesion"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old man presents to the emergency department with 1-month of progressive dyspnea, decreased exercise tolerance, and inability to sleep flat on his back. He says that he been getting increasingly short of breath over the past few years; however, he attributed these changes to getting older. He started becoming very concerned when he was unable to climb the stairs to his apartment about 3 weeks ago. Since then, he has been experiencing shortness of breath even during activities of daily living. His past medical history is significant for heroin and cocaine use as well as periods of homelessness. Physical exam reveals a gallop that occurs just after the end of systole. Which of the following could lead to the same pathology that is seen in this patient?", "answer": "Vitamin B1 deficiency", "options": {"A": "Amyloid production", "B": "Myosin mutation", "C": "Radiation therapy", "D": "Turner syndrome", "E": "Vitamin B1 deficiency"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman presents to her gynecologist as part of her follow-up for her abnormal pap test a year ago. She has a normal menstrual cycle and has never been pregnant. She does not take oral contraceptive pills, as she is sexually inactive. She denies the use of any illicit drugs. Conventional cytology from her cervix uteri is done, which reveals pathological findings suggestive of a low-grade squamous intraepithelial lesion as shown in the photograph below. The same test last year revealed normal histological findings. What is the most likely process leading to these pathological findings in this patient’s pap smear?", "answer": "Dysplasia", "options": {"A": "Hyperplasia", "B": "Hypertrophy", "C": "Atrophy", "D": "Dysplasia", "E": "Anaplasia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old man presents with unremitting diarrhea that has lasted for 2 weeks. He describes his bowel movements as watery, non-bloody, foul-smelling, and greasy. He also has cramping abdominal pain associated with the diarrhea. He says that his symptoms started right after he returned from a father-son camping trip to the mountains. His son has similar symptoms. His vital signs include: pulse 78/min, respiratory rate 15/min, temperature 37.2°C (99.0°F), and blood pressure 120/70 mm Hg. A stool sample is obtained and microscopic analysis is significant for the findings shown in the image below. Which of the following pathogens is most likely responsible for this patient’s condition?", "answer": "Giardia lamblia", "options": {"A": "Bacillus cereus", "B": "Campylobacter jejuni", "C": "Clostridium difficile", "D": "Giardia lamblia", "E": "Yersinia enterocolitica"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old woman presents to the emergency department with swelling of her face and abdominal pain. She states she was outside doing yard work when her symptoms began. The patient has a past medical history of recently diagnosed diabetes and hypertension. Her current medications include lisinopril, metformin, and glipizide. Her temperature is 99.5°F (37.5°C), blood pressure is 149/95 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 99% on room air. On physical exam, the patient's cardiac and pulmonary exam are within normal limits. Dermatologic exam reveals edema of her hands, lips, and eyelids. There is mild laryngeal edema; however, the patient is speaking clearly and maintaining her airway. Which of the following is appropriate long-term management of this patient?", "answer": "Danazol", "options": {"A": "Fresh frozen plasma", "B": "Ecallantide", "C": "Danazol", "D": "Discontinue metformin", "E": "Prednisone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 40-year-old man comes to the physician because of a 5-month history of watery diarrhea and episodic crampy abdominal pain. He has no fever, nausea, or vomiting. Over the past 6 months, he has had a 1.8-kg (4-lb) weight loss, despite experiencing no decrease in appetite. His wife has noticed that sometimes his face and neck become red after meals or when he is in distress. A year ago, he was diagnosed with asthma. He has hypertension. Current medications include an albuterol inhaler and enalapril. He drinks one beer daily. His temperature is 36.7°C (98°F), pulse is 85/min, and blood pressure is 130/85 mm Hg. The lungs are clear to auscultation. A grade 2/6 systolic murmur is heard best at the left sternal border and fourth intercostal space. The abdomen is soft, and there is mild tenderness to palpation with no guarding or rebound. The remainder of the physical examination shows no abnormalities. A complete blood count is within the reference range. Without treatment, this patient is at greatest risk for which of the following conditions?", "answer": "Dementia", "options": {"A": "Asphyxia", "B": "Achlorhydria", "C": "Megaloblastic anemia", "D": "Dementia", "E": "Intestinal fistula"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old boy is brought to the emergency department by his parents because of crushing chest pain, nausea, and vomiting for the past 2 hours. The pain is constant and radiates to his left shoulder. Over the past year, he has been admitted to the hospital twice for deep vein thrombosis. He has a history of learning disability and has been held back three grades. The patient is at the 99th percentile for length and the 45th percentile for weight. His pulse is 110/min, respirations are 21/min, and blood pressure is 128/84 mm Hg. His fingers are long and slender, and his arm span exceeds his body height. Electrocardiography shows ST-segment elevation in leads V1 and V2. His serum troponin I concentration is 2.0 ng/mL (N ≤ 0.04). Coronary angiography shows 90% occlusion of the proximal left anterior descending artery. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Downward lens subluxation", "options": {"A": "Bilateral gynecomastia", "B": "Downward lens subluxation", "C": "Macroorchidism", "D": "Saccular cerebral aneurysms", "E": "Ascending aortic aneurysm"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-year-old Caucasian male presents with a temperature of 38°C. During the physical exam, the patient complains of pain when his femur is palpated. The patient's parents state that the fever started a few days after they noticed a honey-colored crusting on the left upper lip of the child's face. Culture of the bacteria reveals a catalase-positive, gram-positive cocci. Which of the following bacteria is most likely to be found in a biopsy of the child's left femur?", "answer": "Staphylococcus aureus", "options": {"A": "Staphylococcus aureus", "B": "Staphylococcus saprophyticus", "C": "Streptococcus pyogenes", "D": "Clostridium perfingens", "E": "Escherichia coli"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 46-year-old woman complains of chronic cough for the past 3 weeks. She was recently diagnosed with hypertension and placed on an angiotensin receptor blocker therapy (ARBs). Chest X-ray shows large nodular densities bilaterally. Bronchial biopsy showed granulomatous inflammation of the pulmonary artery. Lab investigations showed a positive cANCA with a serum creatinine of 3.6 mg/dL. Urine analysis shows RBC casts and hematuria. Which is the most likely cause of this presentation?", "answer": "Granulomatosis with polyangiitis", "options": {"A": "Microscopic polyangitis", "B": "Churg-Strauss syndrome", "C": "Polyarteritis nodosa", "D": "Hypertensive medication", "E": "Granulomatosis with polyangiitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old man comes to the physician because of recurrent episodes of palpitations, chest pain, shortness of breath, sweating, and dizziness over the past 4 months. These episodes are accompanied by intense fear of “losing control” over himself. Most of the episodes have occurred at work in situations when it would have been unacceptable to leave, such as during team meetings. The last episode occurred at home right before this visit, after he noticed that he was running late. He has been otherwise healthy. He occasionally drinks a beer or a glass of wine. Vital signs are within normal limits. Cardiopulmonary examination shows no abnormalities. Thyroid function studies and an ECG show no abnormalities. Given his symptoms, this patient is at greatest risk of developing which of the following?", "answer": "Depressed mood and feeling of guilt", "options": {"A": "Preoccupation with an observed flaw in physical appearance", "B": "Abnormally elevated mood and flight of ideas", "C": "Depressed mood and feeling of guilt", "D": "Fear of spiders and heights", "E": "Disorganized speech and delusions"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old woman presents with shortness of breath and left-sided chest pain for a week. She says that her breathlessness is getting worse, and the chest pain is especially severe when she takes a deep breath. The patient denies any similar symptoms in the past. Her past medical history is insignificant except for occasional heartburn. She currently does not take any medication. She is a nonsmoker and drinks alcohol occasionally. She denies the use of any illicit drugs including marijuana. Vital signs are: blood pressure 122/78 mm Hg, pulse 67/min, respiratory rate 20/min, temperature 37.2°C (99.0°F). Her physical examination is remarkable for diminished chest expansion on the left side, absence of breath sounds at the left lung base, and dullness to percussion and decreased tactile fremitus on the left. A plain radiograph of the chest reveals a large left-sided pleural effusion occupying almost two-thirds of the left lung field. Thoracentesis is performed, and 2 L of fluid is drained from the thorax under ultrasound guidance. Which of the following patient positions and points of entry is the safest for performing a thoracentesis in this patient?", "answer": "With the patient in the sitting position, below the tip of the scapula midway between the spine and the posterior axillary line on the superior margin of the eighth rib", "options": {"A": "With the patient in the sitting position, below the tip of the scapula midway between the spine and the posterior axillary line on the superior margin of the eighth rib", "B": "With the patient in the sitting position, just above the fifth rib in the anterior axillary line", "C": "With the patient in the sitting position, at the midclavicular line on the second intercostal space", "D": "With the patient in the supine position, just above the fifth rib in the midaxillary line", "E": "With the patient in the supine position, in the fifth intercostal space right below the nipple"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman presents to the clinic with complaints of occasional low-grade fever and joint pain for 1 month. She also complains of morning stiffness in the proximal interphalangeal joints of both hands, which lasts for 5 to 10 minutes. She recently noticed a pink rash on her nose and cheekbones. Her family history is significant for similar complaints in her mother. She is not taking any medications. On examination, her temperature is 37.6°C (99.6°F), pulse is 74/min, blood pressure is 110/70 mm Hg, and respirations are 18/min. Aphthous ulcers are noted on her oral mucosa. Which of the following tests would be most specific for confirming the diagnosis in this patient?", "answer": "Anti-double stranded DNA (dsDNA) antibodies", "options": {"A": "Anti-double stranded DNA (dsDNA) antibodies", "B": "Anti-histone antibodies", "C": "Anti-topoisomerase (anti-Scl 70) antibodies", "D": "Anti-Ro antibodies", "E": "Antinuclear antibodies (ANA)"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 50-year-old man presents to a physician with recurrent episodes of coughing over the last 3 years. He mentions that his cough has been accompanied by expectoration during 5–6 consecutive months every year for the last 3 years and he experiences breathing difficulty on exertion. He has been a smoker for the last 10 years. There is no family history of allergy. He was prescribed inhaled corticosteroids and an inhaled bronchodilator 1 month previously, but there has been no improvement. There is no history of fever or breathing difficulty at present. On physical examination his temperature is 37.0°C (98.6°F), the pulse is 84/min, the blood pressure 126/84 mm Hg, and the respiratory rate is 20/min. Auscultation of his chest reveals coarse rhonchi and wheezing bilaterally. His sputum is mucoid and microscopic examination shows predominant macrophages. His chest radiogram (posteroanterior view) shows flattening of the diaphragm, increased bronchovascular markings, and mild cardiomegaly. If lung biopsy is carried out, which of the following microscopic findings is most likely to be present in this patient?", "answer": "Hyperplasia of the mucus glands in the airways", "options": {"A": "Destruction of the pulmonary capillary bed", "B": "Variable-sized cysts against a background of densely scarred lung tissue", "C": "Hyperplasia of the mucus glands in the airways", "D": "Eosinophilic infiltration of the airways", "E": "Ossification of bronchial cartilage"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old woman comes to the physician for a routine health maintenance examination. Her last visit was 3 years ago. She feels well. One year ago, she underwent a tubectomy after the delivery of her third child. She does not take any medications. Physical examination shows no abnormalities. A Pap smear shows a high-grade squamous intraepithelial lesion. Which of the following is the most appropriate next step in management?", "answer": "Loop electrosurgical excision procedure", "options": {"A": "Repeat cytology in 3 months", "B": "Laser ablative therapy", "C": "Loop electrosurgical excision procedure", "D": "Repeat cytology at 12 months", "E": "Colposcopy with endometrial sampling"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 36-year-old man presents to his physician with an acute burning retrosternal sensation with radiation to his jaw. This sensation began 20 minutes ago when the patient was exercising at the gym. It does not change with position or with a cough. The patient’s vital signs include: blood pressure is 140/90 mm Hg, heart rate is 84/min, respiratory rate is 14/min, and temperature is 36.6℃ (97.9℉). Physical examination is only remarkable for paleness and perspiration. The patient is given sublingual nitroglycerin, the blood is drawn for an express troponin test, and an ECG is going to be performed. At the moment of performing ECG, the patient’s symptoms are gone. ECG shows increased R amplitude in I, II V3-V6, and ST depression measuring for 0.5 mm in the same leads. The express test for troponin is negative. Which of the following tests would be reasonable to perform next to confirm a diagnosis in this patient?", "answer": "Exercise stress testing", "options": {"A": "Blood test for CPK-MB", "B": "Echocardiography", "C": "Chest radiography", "D": "CT angiography", "E": "Exercise stress testing"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 58-year-old woman with a past medical history significant for major depressive disorder and generalized anxiety syndrome presents after having undergone menopause 3 years earlier. Today, she complains of intolerable hot flashes and irritability at work and at home. The remainder of the review of systems is negative. Physical examination reveals a grade 2/6 holosystolic murmur best heard at the apex, clear breath sounds, and normal abdominal findings. Her vital signs are all within normal limits. She requests hormonal replacement therapy (HRT) for the relief of her symptoms. Which of the following additional pieces of past medical history would make HRT contraindicated in this patient?", "answer": "Known or suspected personal history of breast cancer", "options": {"A": "Family history of breast cancer", "B": "Known or suspected personal history of breast cancer", "C": "Family history of endometrial cancer", "D": "Osteoporosis", "E": "Failure of symptomatic control with SSRI/SNRI"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old man comes to the physician for a 1-week history of fever and generalized fatigue. Yesterday, he developed a rash all over his body. Two months ago, he had a painless lesion on his penis that resolved a few weeks later without treatment. He has asthma. Current medications include an albuterol inhaler. He is currently sexually active with 3 different partners. He uses condoms inconsistently. Vital signs are within normal limits. He has a diffuse maculopapular rash involving the trunk, extremities, palms, and soles. An HIV test is negative. Rapid plasma reagin (RPR) and fluorescent treponemal antibody absorption test (FTA-ABS) are positive. The patient receives a dose of intramuscular benzathine penicillin G. Two hours later, he complains of headache, myalgias, and chills. His temperature is 38.8°C (101.8°F) , pulse is 105/min, respirations are 24/min, and blood pressure is 98/67 mm Hg. Which of the following is the most appropriate pharmacotherapy?", "answer": "Ibuprofen", "options": {"A": "Ceftriaxone", "B": "Ibuprofen", "C": "Epinephrine", "D": "Methylprednisolone", "E": "Phenylephrine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A pharmaceutical company is testing a new antidepressant. During phase I of the drug trial, healthy volunteers are recruited, and the effects of the drug on the cardiovascular system are studied. A graphical representation of the volume-pressure relationship of the left ventricle of the heart is given below with the dashed line representing post medication changes. Which of the following is the most likely mechanism of the drug being studied?", "answer": "Gq-coupled receptor activation", "options": {"A": "Selective AT1 receptor blockade", "B": "Gs-coupled receptor activation", "C": "Gq-coupled receptor activation", "D": "M2 receptor activation", "E": "Delaying phase 0 of the pacemaker action potential"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A baby is delivered at 39 weeks without complications. Upon delivery, there are obvious craniofacial abnormalities, including micrognathia, cleft lip, and cleft palate. On further inspection, downward slanting eyes and malformed ears are seen. The child has an APGAR score of 9 and 9 at 1 and 5 minutes respectively. There are no signs of cyanosis or evidence of a heart murmur. Which of the following is the most likely underlying cause of this patient’s presentation at birth?", "answer": "Mutation in the TCOF1 gene", "options": {"A": "Retinoic acid use during gestation", "B": "Trisomy 18", "C": "Mutation of the SOX9 gene", "D": "Microdeletion at chromosome 22q14", "E": "Mutation in the TCOF1 gene"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 46-year-old woman with a history of type II diabetes mellitus is started on lisinopril for newly diagnosed hypertension by her primary care physician. At a follow-up appointment several weeks later, she reports decreased urine output, and she is noted to have generalized edema. Her creatinine is elevated compared to baseline. Given her presentation, which of the following changes in renal arteriolar blood flow and glomerular filtration rate (GFR) have likely occurred?", "answer": "Renal efferent arteriole vasodilation; decreased GFR", "options": {"A": "Renal afferent arteriole vasoconstriction; decreased GFR", "B": "Renal afferent arteriole vasodilation; increased GFR", "C": "Renal efferent arteriole vasoconstriction; increased GFR", "D": "Renal efferent arteriole vasodilation; decreased GFR", "E": "Renal efferent arteriole vasodilation; no change in GFR"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 20-year-old female with type I diabetes mellitus presents to the emergency department with altered mental status. Her friend said that she has been out late either studying for upcoming tests or attending prayer group meetings. As far as the friend can recollect, the patient appeared to be in her usual state of health until only two days ago, when she was prescribed trimethoprim-sulfamethoxazole for a urinary tract infection. The patient complained that the medication was making her feel nauseous and bloated. The patient also relies on glargine and lispro for glycemic control. Her temperature is 100.5°F (38.1°C), blood pressure is 95/55 mmHg, pulse is 130/min, and respirations are 30/min. Her pupils are equal and reactive to light bilaterally. The remainder of the physical exam is unremarkable. Her basic metabolic panel is displayed below:\n\nSerum:\nNa+: 116 mEq/L\nCl-: 90 mEq/L\nK+: 5.0 mEq/L\nHCO3-: 2 mEq/L\nBUN: 50 mg/dL\nGlucose: 1,200 mg/dL\nCreatinine: 1.5 mg/dL\n\nWhich of the following is true regarding this patient's presentation?", "answer": "Hyperkalemia is independent of the patient's total body potassium stores", "options": {"A": "Hyponatremia is independently associated with a poor prognosis", "B": "Hyperkalemia is independent of the patient's total body potassium stores", "C": "Hyperglycemia to this magnitude supports hyperglycemic hyperosmolar nonketotic syndrome", "D": "Azotemia independently contributes to the patient's encephalopathy", "E": "Hypochloremia to this magnitude supports a pure anion-gap metabolic acidosis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old woman visits the physician with complaints of difficulty swallowing and recurrent vomiting for the past 6 months. She even noticed food particles in her vomit a few hours after eating her meals. She has lost about 3.0 kg (6.6 lb) over the past 4 months. Her history is significant for a trip to Argentina last year. Her past medical history is insignificant. She is a non-smoker. On examination, her blood pressure is 118/75 mm Hg, respirations are 17/min, pulse is 78/min, temperature is 36.7°C (98.1°F), and her BMI is 24 kg/m². There is no abdominal tenderness, distension, or evidence of jaundice. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Barium XR", "options": {"A": "Biopsy", "B": "Surgery", "C": "Barium XR", "D": "Antibiotic therapy", "E": "Routine blood tests"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old woman presents to the emergency room with severe right lower quadrant abdominal pain. She has a history of tubal ligation 3 years ago and a history of chlamydia treated 15 years ago. She usually has very regular periods, but her last menstrual period was 10 weeks ago. On exam, she is afebrile, HR 117, blood pressure of 88/56 mmHg, and she has peritoneal signs including rebound tenderness. Urine Beta-hCG is positive. Hgb is 9.9 g/dL. What is the appropriate treatment?", "answer": "Laparotomy", "options": {"A": "Serial beta-hCG levels", "B": "Azithromycin", "C": "Methotrexate", "D": "Laparotomy", "E": "Blood transfusion"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 47-year-old female comes to the emergency department because of increasing back pain for the past 2 weeks. She is unable to perform her daily chores. One month ago, she fell and hurt her back while working outside in the garden. The pain subsided with over-the-counter acetaminophen. She underwent a left mastectomy 1 year ago for breast cancer. She has type 2 diabetes mellitus. Current medications include metformin, sitagliptin, and a multivitamin. She appears uncomfortable. Her temperature is 38.9°C (102.0°F), pulse is 101/min, and blood pressure is 110/80 mm Hg. Examination of the back shows thoracic vertebral tenderness. She has mild stiffness on neck flexion. Muscle strength is decreased in the lower extremities. Deep tendon reflexes are 2+ bilaterally. Sensation to pain, fine touch, temperature, and proprioception is intact. Her hemoglobin concentration is 13.1 g/dL and leukocyte count is 19,300/mm3. Which of the following is the most appropriate next step in management?", "answer": "MRI of the spine", "options": {"A": "Serum protein electrophoresis", "B": "X-rays of the spine", "C": "Methylprednisone therapy", "D": "Vancomycin and nafcillin therapy", "E": "MRI of the spine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 67-year-old woman comes to the clinic complaining of progressive fatigue over the past 4 months. She noticed that she is feeling increasingly short of breath after walking the same distance from the bus stop to her home. She denies chest pain, syncope, lower extremity edema, or a cough. She denies difficulty breathing while sitting comfortably, but she has increased dyspnea upon walking or other mildly strenuous activity. Her past medical history includes mild osteoporosis and occasional gastric reflux disease. She takes oral omeprazole as needed and a daily baby aspirin. The patient is a retired accountant and denies smoking history, but she does admit to 1 small glass of red wine daily for the past 5 years. Her diet consists of a Mediterranean diet that includes fruits, vegetables, and fish. She states that she has been very healthy previously, and managed her own health without a physician for the past 20 years. On physical examination, she has a blood pressure of 128/72 mm Hg, a pulse of 87/min, and an oxygen saturation of 94% on room air. HEENT examination demonstrates mild conjunctival pallor. Lung and abdominal examinations are within normal limits. Heart examination reveals a 2/6 systolic murmur at the right upper sternal border.\nThe following laboratory values are obtained:\nHematocrit 29%\nHemoglobin 9.8 mg/dL\nMean red blood cell volume 78 fL\nPlatelets 240,000/mm3\nWhite blood cells 6,000/mm3\nWhat is the most likely reticulocyte range for this patient?", "answer": "< 1%", "options": {"A": "< 1%", "B": "0%", "C": "> 1.5%", "D": ">5%", "E": ">7%"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old man comes to the emergency department because of worsening shortness of breath, bilateral leg swelling, and constant chest pain which is not related to exertion for the last 2 weeks. The patient underwent an aortic valve replacement surgery for chronic aortic regurgitation 1 year ago, and his postoperative course was uncomplicated. He denies smoking or alcohol use. His blood pressure is 80/50 mm Hg, temperature is 36.6°C (97.9°F), and pulse is regular at 110/min. On physical examination, jugular veins are distended, +1 pitting edema is present on both ankles, and heart sounds are distant. Chest X-ray is shown in the exhibit. Transthoracic echocardiography shows large pericardial effusion, chamber collapse, and respiratory variation of ventricular filling. ECG of this patient will most likely show which of the following?", "answer": "Low voltage and beat-to-beat variations in the height of QRS complexes", "options": {"A": "Diffuse concave ST elevation and PR depression", "B": "S wave in lead I, Q wave with T-wave inversion in lead III", "C": "Right atrial enlargement, right ventricular enlargement, and right axis deviation", "D": "Low voltage and beat-to-beat variations in the height of QRS complexes", "E": "Tachycardia with discrete P waves with at least three different morphologies"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man presents to his primary care physician for a follow-up appointment. The patient was the front seat driver in a head-on collision which resulted in a femur and pelvic fracture which was treated appropriately. The patient spent 3 weeks in the hospital and was then discharged 2 weeks ago. The patient has a past medical history of diabetes, hypertension, and dyslipidemia. He smokes 3 packs of cigarettes per day and drinks 4 alcoholic beverages every night. The patient says that he has been attempting to engage in sexual activities with his wife but has been unable to do so. He states this has never been a problem for him before. He also reports new-onset minor headaches and trouble sleeping for which he is taking trazodone. Which of the following is the most likely diagnosis?", "answer": "Neurologic damage", "options": {"A": "Atherosclerotic change", "B": "Increased prolactin", "C": "Medication changes", "D": "Neurologic damage", "E": "Psychologic"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old woman, gravida 2 para 1, at 31 weeks' gestation is brought to the emergency department because of confusion. Three days ago, she developed diffuse abdominal pain, malaise, nausea, and vomiting. She has a 2-year history of gastroesophageal reflux disease. Four months ago, she spent 2 weeks in Belize for her honeymoon. Her previous pregnancy was complicated by preeclampsia, which was terminated by induction of labor at 37 weeks' gestation. Her only medication is esomeprazole. She appears tired. Her temperature is 38°C (100°F), pulse is 82/min, respirations are 19/min, and blood pressure is 118/79 mm Hg. She responds to sound and communicates in short sentences. Examination shows yellowish discoloration of the sclera and abdominal distention. There is tenderness to palpation of the right upper quadrant. When she is asked to hold her hands in extension, there is a notable flapping tremor. Her uterus is consistent in size with a 31-week gestation. Laboratory studies show:\nHematocrit 26%\nPlatelet count 90,000/mm3\nLeukocyte count 10,500/mm3\nProthrombin time (PT) 34 seconds\nPartial thromboplastin time (PTT) 48 seconds\nSerum\nTotal protein 5.0 g/dL\nAlbumin 2.6 g/dL\nGlucose 62 mg/dL\nCreatinine 2.1 mg/dL\nBilirubin, total 9.2 mg/dL\nIndirect 4.2 mg/dL\nAspartate aminotransferase 445 U/L\nAlanine aminotransferase 485 U/L\nAlkaline phosphatase 36 U/L\nAnti-HAV IgM antibody negative\nAnti-HAV IgG antibody positive\nHBsAG negative\nAnti-HBs antibody positive\nAnti-HBc antibody negative\nAnti-HCV antibody negative\nUrine studies show no abnormalities. Which of the following is the most likely diagnosis?\"", "answer": "Acute fatty liver of pregnancy", "options": {"A": "Preeclampsia", "B": "Acute fatty liver of pregnancy", "C": "HELLP syndrome", "D": "Intrahepatic cholestasis of pregnancy", "E": "Acute viral hepatitis B"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 38-year-old woman presents with worsening fatigue and difficulty talking for the last few hours. Past medical history is significant for type 2 diabetes mellitus, managed with metformin and insulin. Additional current medications are a pill to ''calm her nerves'' that she takes when she has to perform live on stage for work. On physical examination, the patient is lethargic, easily confused, and has difficulty responding to questions or commands. There is also significant diaphoresis of the face and trunk present. Which of the following is the most likely etiology of this patient’s current symptoms?", "answer": "Masking of sympathetic nervous system dependent symptoms", "options": {"A": "Masking of sympathetic nervous system dependent symptoms", "B": "Increased GABAergic activity", "C": "Anticholinergic side effect", "D": "Direct opiate mu receptor stimulation", "E": "Hyperosmolar nonketotic coma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 15-year-old boy is brought to the emergency room for evaluation of malaise, dyspnea, and yellow skin and sclera. On examination, he is tachycardic, tachypneic, and the O2 saturation is less than 90%. The levels of unconjugated bilirubin and hemoglobinemia are increased, and there is an increased number of reticulocytes in the peripheral blood. What is the most likely diagnosis?", "answer": "Hemolytic anemia", "options": {"A": "Anemia of chronic disease", "B": "Acute leukemia", "C": "Sideropenic anemia", "D": "Hemolytic anemia", "E": "Aplastic anemia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 12-year-old boy presents to the emergency department with severe abdominal pain and nausea. He first began to have diffuse abdominal pain 15 hours prior to presentation. Since then, the pain has moved to the right lower quadrant. On physical exam he has tenderness to light palpation with rebound tenderness. Lifting his right leg causes severe right lower quadrant pain. Which of the following nerves roots was most likely responsible for the initial diffuse pain felt by this patient?", "answer": "T10", "options": {"A": "C6", "B": "T4", "C": "T7", "D": "T10", "E": "L1"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old woman is admitted to the hospital with sepsis and treated with gentamicin. One week after her admission, she develops oliguria and her urine shows muddy brown casts on light microscopy. Days later, her renal function begins to recover, but she complains of weakness and develops U waves on EKG as shown in Image A. Which laboratory abnormality would you most expect to see in this patient?", "answer": "Hypokalemia", "options": {"A": "Hypocalcemia", "B": "Hypokalemia", "C": "Hyponatremia", "D": "Hypoglycemia", "E": "Hypermagnesemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A plain CT scan of the patient's head is performed immediately and the result is shown. His temperature is 37.1°C (98.8°F), pulse is 101/min and blood pressure is 174/102 mm Hg. Which of the following is the most appropriate next step in management?", "answer": "Intravenous alteplase therapy", "options": {"A": "Decompressive surgery", "B": "Intravenous labetalol therapy", "C": "Oral aspirin therapy", "D": "Intravenous alteplase therapy", "E": "Surgical clipping"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old Caucasian male is being treated for atrial fibrillation and angina complains of dyspnea on exertion. On exam, his heart rate 104-115/min and irregularly irregular at rest. He has no chest pain. You believe his rate control for atrial fibrillation is suboptimal and the likely cause of his dyspnea. You are considering adding verapamil to his current metoprolol for additional rate control of his atrial fibrillation. Which of the following side effects should you be most concerned about with this additional medication?", "answer": "Hypotension", "options": {"A": "Diarrhea", "B": "Shortening of action potential length at the AV node", "C": "Tachycardia", "D": "Hypotension", "E": "Torsades de pointes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-month-old male presents to the pediatrician with his mother for a well child visit. The patient drinks 4 ounces of conventional cow’s milk formula every three hours. He usually stools once per day, and urinates up to six times per day. His mother reports that he regurgitates a moderate amount of formula through his nose and mouth after most feeds. He does not seem interested in additional feeding after these episodes of regurgitation, and he has become progressively more irritable around meal times. The patient is starting to refuse some feeds. His mother denies ever seeing blood or streaks of red in his stool, and she denies any family history of food allergies or dermatological problems. The patient’s weight was in the 75th percentile for weight throughout the first month of life. Four weeks ago, he was in the 62nd percentile, and he is now in the 48th percentile. His height and head circumference have followed similar trends. On physical exam, the patient smiles reciprocally and can lift his head and chest when in the prone position. His abdomen is soft, non-tender, and non-distended.\n\nWhich of the following is the best next step in management?", "answer": "Counsel on positioning and thickening feeds", "options": {"A": "Obtain abdominal ultrasound", "B": "Counsel on positioning and thickening feeds", "C": "Initiate proton pump inhibitor", "D": "Provide reassurance", "E": "Switch to hydrolyzed formula"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 18-month-old boy is brought to the emergency department after losing consciousness. His mother states that he was running with other kids in the park when he suddenly fell down and became unresponsive for less than 1 minute. He has not had any immunizations due to their religious beliefs. The parents report that he plays with other children, but tires easily. He has had difficulty feeding, but there was no follow-up with a pediatrician. The heart rate was 120/min and the oxygen saturation was 91%. The height is in the 40th percentile and the weight is in the 50th percentile. On examination, the boy is crying with perioral cyanosis. The lung sounds are clear. S-1 is normal and there is a single S-2. A grade 2/6 systolic ejection murmur is appreciated at the left upper sternal border. When the child squats, the murmur is intensified and the cyanosis improves. What is the most appropriate next step in the management of this patient?", "answer": "Morphine, oxygen, IV fluids, and beta blockers", "options": {"A": "Diazepam", "B": "Morphine, oxygen, nitroglycerin, and aspirin", "C": "Morphine, oxygen, IV fluids, and beta blockers", "D": "Observation and reassurance", "E": "Antibiotics and supportive care"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old man is admitted to the emergency department with a gunshot wound to the abdomen. He complains of weakness and diffuse abdominal pain. Morphine is administered and IV fluids are started by paramedics at the scene. On admission, the patient’s blood pressure is 90/60 mm Hg, heart rate is 103/min, respiratory rate is 17/min, the temperature is 36.2℃ (97.1℉), and oxygen saturation is 94% on room air. The patient is responsive but lethargic. The patient is diaphoretic and extremities are pale and cool. Lungs are clear to auscultation. Cardiac sounds are diminished. Abdominal examination shows a visible bullet entry wound in the left upper quadrant (LUQ) with no corresponding exit wound on the flanks or back. The abdomen is distended and diffusely tender with a rebound. Aspiration of the nasogastric tube reveals bloody contents. Rectal examination shows no blood. Stool guaiac is negative. Which of the following is the next best step in management?", "answer": "Exploratory laparotomy", "options": {"A": "Exploratory laparotomy", "B": "Focused assessment with sonography for trauma (FAST)", "C": "Abdominal X-ray", "D": "Abdominal CT", "E": "Diagnostic peritoneal lavage"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old woman presents with fatigue, depressed mood, weight gain, and constipation. She gradually developed these symptoms over the past 6 months. She is G2P2 with the last pregnancy 9 months ago. She had a complicated delivery with significant blood loss requiring blood transfusions. She used to have a regular 28-day cycle but notes that recently it became irregular with duration lasting up to 40 days, more pain, and greater blood loss. She does not report any chronic conditions, and she is not on any medications. She is a current smoker with a 10-pack-year history. Her blood pressure is 130/80 mm Hg, heart rate is 54/min, respiratory rate is 11/min, and temperature is 35.8°C (96.4°F). Her skin is dry and pale with a fine scaling over the forearms and shins. There is a mild, non-pitting edema of the lower legs. Her lungs are clear to auscultation. Cardiac auscultation does not reveal any pathological sounds or murmurs although S1 and S2 are dulled at all points of auscultation. The abdomen is mildly distended and nontender on palpation. Neurological examination is significant for decreased deep tendon reflexes. Her blood tests show the following results:\nErythrocytes count 3.4 million/mm3\nHb 12.2 mg/dL\nMCV 90 μm3\nReticulocyte count 0.3%\nLeukocyte count 5,600/mm3\nSerum vitamin B12 210 ng/mL\nT4 total 1.01 μU/mL\nT4 free 0.6 μU/mL\nTSH 0.2 μU/mL\nWhich of the following lab values should be used to monitor treatment in this patient?", "answer": "Free T4", "options": {"A": "Free T4", "B": "Vitamin B12", "C": "Total T3", "D": "MCV", "E": "TSH"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 74-year-old right-handed woman was referred to the hospital due to concerns of a stroke. In the emergency department, the initial vital signs included blood pressure of 159/98 mm Hg, heart rate of 88/min, and respiratory rate of 20/min. She exhibited paucity of speech and apathy to her condition, although she complied with her physical examination. The initial neurologic evaluation included the following results:\nAwake, alert, and oriented to person, place, and time\nNo visual field deficits\nRight-sided gaze deviation with full range of motion with doll’s head maneuver\nNo facial asymmetry\nGrossly intact hearing\nNo tongue deviation, equal palatal elevation, and good guttural sound production\nAbsent pronator or lower extremity drift\nDecreased sensation to light touch on the right leg\nNormal appreciation of light touch, pressure, and pain\nNormal proprioception and kinesthesia\nManual muscle testing:\n5+ right and left upper extremities\n5+ right hip, thigh, leg, and foot\n3+ left hip and thigh\n2+ left leg and foot\nA head computed tomography (CT) scan and a head magnetic resonance imaging (MRI) confirmed areas of ischemia. Which artery is the most likely site of occlusion?", "answer": "Right anterior cerebral artery", "options": {"A": "Right anterior cerebral artery", "B": "Right middle cerebral artery stem (M1)", "C": "Superior division of the right middle cerebral artery", "D": "Inferior division of the right middle cerebral artery", "E": "Inferior division of the left middle cerebral artery"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old woman, with end-stage renal disease (ESRD) on hemodialysis, presents with pain, swelling and discoloration of her right leg and foot. She says that she started twice-weekly hemodialysis 2 weeks ago and has had no issues until 1 week ago when she noticed a warm, painful swelling of the back of her right leg and right foot after finishing her dialysis session. Over the week, she says these symptoms have steadily worsened and, in the last few days, her right foot has become discolored. Past medical history is significant for ESRD secondary to long-standing hypertension. Current medications are verapamil 200 mg orally daily and unfractionated heparin that is given during hemodialysis. Her vital signs include: temperature 37.0°C (98.6°F), blood pressure 145/75 mm Hg, pulse 88/min, respirations 15/min, and oxygen saturation 99% on room air. On physical examination, the patient is alert and cooperative. The cardiac exam is normal. Lungs are clear to auscultation. The abdomen is soft and nontender with no hepatosplenomegaly. The right calf is swollen, warm, and erythematous. Physical findings of the patient’s right foot are shown in the exhibit. Laboratory findings are significant for the following:\nSodium 141 mEq/L\nPotassium 4.9 mEq/L\nChloride 104 mEq/L\nBicarbonate 25 mEq/L\nBUN 32 mg/dL\nCreatinine 3.1 mg/dL\nGlucose (fasting) 75 mg/dL\n  Bilirubin, conjugated 0.5 mg/dL       \nBilirubin, total 1.0 mg/dL\nAST (SGOT) 22 U/L       \nALT (SGPT) 23 U/L       \nAlkaline phosphatase 56 U/L\n  Bleeding time 19 min      \nProthrombin time (PT) 11 s   \nPartial thromboplastin time (PTT) 30 s\n        WBC 8,500/mm3       \nRBC 4.10 x 106/mm3\nHematocrit 41.5%\nHemoglobin 13.5 g/dL       \nPlatelet count 100,000/mm3 (previously 200,000/mm3)\nWhich of the following is the next best diagnostic step in this patient?", "answer": "Heparin/PF4 enzyme-linked immunosorbent assay (ELISA)", "options": {"A": "Heparin/PF4 enzyme-linked immunosorbent assay (ELISA)", "B": "Functional assay for factor VIII", "C": "Serotonin release assay", "D": "Peripheral blood smear", "E": "Flow cytometry for CD55"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old man is brought to the emergency room because of pain in his right hip. He was found lying on the floor several hours after falling onto his right side. Ten years ago, he received a renal transplant from a living related donor. He has a 4-year history of type 2 diabetes. Current medications include prednisone, cyclosporine, and metformin. Examination shows a shortened and externally rotated right leg. There is extensive bruising over the right buttock and thigh. X-ray of the right hip shows a displaced femoral neck fracture. The patient is resuscitated in the emergency room and taken to surgery for a right total hip replacement. Post-operative laboratory studies show:\nHemoglobin 11.2 g/dL\nSerum\nNa+ 148 mmol/L\nK+ 7.1 mmol/L\nCl- 119 mmol/L\nHCO3- 18 mmol/L\nUrea nitrogen 22 mg/dL\nCreatinine 1.6 mg/dL\nGlucose 200 mg/dL\nCreatine kinase 1,562 U/L\nHis urine appears brown. Urine dipstick is strongly positive for blood. ECG shows peaked T waves. Intravenous calcium gluconate is administered. What is the most appropriate next step in management?\"", "answer": "Administer intravenous insulin and glucose", "options": {"A": "Administer nebulized albuterol", "B": "Administer intravenous insulin and glucose", "C": "Initiate hemodialysis", "D": "Administer intravenous furosemide and normal saline", "E": "Administer intravenous sodium bicarbonate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "After an initial assessment in the emergency department, the patient is sent for an urgent CT scan of the head. CT scan reveals a mild hypodensity in the left cerebellum. What is the most likely etiology/cause?", "answer": "Arterial dissection", "options": {"A": "Arterial blood leakage", "B": "Arterial dissection", "C": "Cardiac emboli", "D": "Carotid stenosis", "E": "Lacunar infarction"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 56-year-old female presents for initial evaluation by a rheumatologist with a chief complaint of back and joint pain. She says that she has been having mild pain for years, but that the pain has become worse over the course of the last 6 months. She clarifies that the pain is most severe in the mornings just after waking up but seems to improve throughout the day. She also notices that her mouth feels dry and she has difficulty eating dry food such as crackers. Finally, she has the sensation of having bits of sand in her eyes. She denies any past medical history or medication use. Serology for which of the following would most likely be positive in this patient?", "answer": "Anti-Ro and anti-La antibodies", "options": {"A": "Anti-smooth muscle antibody", "B": "Anti-centromere antibody", "C": "Anti-cyclic citrullinated peptide (CCP) antibody", "D": "Anti-Jo1 and anti-Mi2 antibodies", "E": "Anti-Ro and anti-La antibodies"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 50-year-old man presents with a rapid onset of severe, right periorbital pain, an ipsilateral throbbing headache, and blurred vision for the past hour. The patient says he was out walking with his friend when he felt short of breath. His friend gave him a puff of his rescue inhaler because it often relives his breathlessness, but, soon after that, the patient's eye symptoms started. No significant past medical history. His pulse is 100/min and regular, respirations are 18/min, temperature is 36.7°C (98.0°F), and blood pressure 130/86 mm Hg. On physical examination, his right pupil is fixed and dilated. Fundoscopic examination of the right eye is difficult due to 'clouding' of the cornea, and tonometry reveals increased intraocular pressure (IOP). Ibuprofen, acetazolamide, timolol, pilocarpine, and topical prednisolone are administered, but the patient's symptoms are only slightly reduced. Which of the following is the next best step in the management of this patient?", "answer": "Get an urgent ophthalmology consultation.", "options": {"A": "Administer systemic steroids.", "B": "Get an urgent ophthalmology consultation.", "C": "Anesthetize the eye and perform corneal indentation.", "D": "Add latanoprost.", "E": "Perform emergency iridotomy."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old woman comes to the physician for a follow-up examination. She has type 1 diabetes mellitus, end-stage renal disease, and was recently started on erythropoietin for anemia. Her last hemodialysis session was yesterday. Current medications also include insulin, calcitriol, and sevelamer. She appears well. Her pulse is 68/min and regular, respirations are 12/min, and blood pressure is 169/108 mm Hg. Her blood pressure was normal at previous visits. Examination shows normal heart sounds. There are no carotid, femoral, or abdominal bruits. The lungs are clear to auscultation. Laboratory studies show a hemoglobin concentration of 12 g/dL, a serum creatinine concentration of 3.4 mg/dL, and BUN of 20 mg/dL. Which of the following is the most likely cause of this patient's hypertension?", "answer": "Erythropoietin therapy", "options": {"A": "Calcitriol therapy", "B": "Erythropoietin therapy", "C": "Autonomic neuropathy", "D": "Hypervolemia", "E": "Hypoglycemia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old man with alcohol use disorder is brought to the physician by his sister for frequent falls and an unsteady gait over the past 2 months. He has not seen a physician in 10 years. He appears emaciated and inattentive. He is oriented to person only. Physical examination shows a wide-based gait with slow, short steps. Eye examination shows lateral gaze paralysis and horizontal nystagmus. One month later, he dies. Which of the following is the most likely finding on autopsy?", "answer": "Small vessel hemorrhage in mammillary bodies", "options": {"A": "Small vessel hemorrhage in mammillary bodies", "B": "Degeneration of the frontotemporal lobe", "C": "Depigmentation of the substantia nigra", "D": "Widespread atrophy of cerebral cortex", "E": "Atrophy of the caudate and putamen"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 57-year-old woman comes to the physician because of increasing wrinkles on her face and sagging skin. She says that her skin used to be smooth and firm. Examination shows diffuse xerosis and mild atrophy, laxity, and fine wrinkles on the periorbital skin. Which of the following processes is most likely involved in the development of this patient's skin findings?", "answer": "Decrease in elastin fiber assembly", "options": {"A": "Decrease in lysyl oxidase activity", "B": "Decrease in elastin fiber assembly", "C": "Increase in fibroblast activity", "D": "Increase in lipofuscin deposition", "E": "Decreased crosslinking of collagen fibrils"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman presents with an inability to move her right arm or leg. She states that symptoms onset acutely 2 hours ago. Past medical history is significant for long-standing type 1 diabetes mellitus, well-managed with insulin. The patient reports a 15-pack-year smoking history. Family history is significant for breast cancer in her mother at age 66 and her father dying of a myocardial infarction at age 57. Review of systems is significant for excessive fatigue for the past week, and her last menstrual period that was heavier than normal. Her vitals signs include: temperature 38.8°C (101.8°F), blood pressure 105/75 mm Hg, pulse 98/min, respirations 15/min, and oxygen saturation 99% on room air. On physical examination, the patient appears pale and tired. The cardiac exam is normal. Lungs are clear to auscultation. The abdominal exam is significant for splenomegaly. There is a non-palpable purpura present on the lower extremities bilaterally. Conjunctiva and skin are pale. Laboratory results are pending. A peripheral blood smear is shown in the exhibit. Which of the following laboratory findings would least likely be seen in this patient?", "answer": "Elevated creatinine", "options": {"A": "Decreased platelets", "B": "Normal PTT and PT", "C": "Elevated creatinine", "D": "Elevated reticulocyte count", "E": "Elevated bilirubin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 77-year-old male presents to the emergency department because of shortness of breath and chest discomfort. The patient states his ability to withstand activity has steadily declined, and most recently he has been unable to climb more than one flight of stairs without having to stop to catch his breath. On physical exam, the patient has a harsh crescendo-decrescendo systolic murmur heard over the right sternal boarder, with radiation to his carotids. Which of the following additional findings are most likely in this patient?", "answer": "A paradoxically split S2", "options": {"A": "A wide and fixed split S2", "B": "A constant, machine-like murmur heard between the scapulae", "C": "A paradoxically split S2", "D": "A diastolic murmur heard at the cardiac apex", "E": "A high-bitched, blowing, holosystolic murmur"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 3-year-old boy is brought to the family physician by his parents. They are concerned that he has had multiple nosebleeds in the last 6 months and is always sick compared to other children. During this time period they have also noticed the formation of multiple bruises on his extremities and dry-itching skin on his hands, feet and elbow. On physical exam the physician notes moderate splenomegaly. What is the most likely diagnosis in this child?", "answer": "Wiskott-Aldrich Syndrome", "options": {"A": "X-linked Agammaglobulinemia", "B": "Severe Combined Immunodefiency", "C": "Wiskott-Aldrich Syndrome", "D": "Primary Eczema", "E": "Hyperimmunoglobulin E syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old, gravida 1, para 1 woman develops lower abdominal pain and fevers 4 days after undergoing a cesarean delivery under general anesthesia for prolonged labor. Since delivery, she has had malodorous lochia and difficulty breastfeeding due to breast pain. She has not had any shortness of breath or chest pain. She received intravenous intrapartum penicillin for group B streptococcus prophylaxis, but does not take any other medications on a regular basis. She appears ill. Her temperature is 38.8°C (102°F), pulse is 120/min, respirations are 22/min, and blood pressure is 110/70 mm Hg. Examination shows a urinary catheter in place. Breasts are engorged and tender. Nipples are cracked with mild erythema. There is erythema surrounding a mildly tender, dry, low transverse, 12-cm incision in the lower abdomen. Pelvic examination shows dark-red, foul-smelling lochia and uterine tenderness. Her hemoglobin concentration is 9 g/dL, leukocyte count is 16,000/mm3, and platelet count is 300,000/mm3. Which of the following is the most likely cause of this patient's fever?", "answer": "Endometritis", "options": {"A": "Endometritis", "B": "Pyelonephritis", "C": "Normal postpartum fever", "D": "Chorioamnionitis", "E": "Mastitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 67-year-old woman is brought to the emergency department by her caretakers for a change in behavior. The patient lives in a nursing home and was noted to have abnormal behavior, urinary incontinence, and trouble walking. The patient has been admitted to the hospital before for what seems to be negligence from her caretakers. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 120 mEq/L\nCl-: 98 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\n\nUrinalysis is notable for bacteruria without pyuria or nitrates. Physical exam is notable for a confused woman who is unable to answer questions appropriately. She states she has no pain or symptoms and is not sure why she is here. She thinks the year is 1982. Which of the following complications could be seen with treatment of this patient?", "answer": "Osmotic demyelination", "options": {"A": "Autoimmune pontine demyelination", "B": "Central nervous system infection", "C": "Cerebral edema", "D": "Diarrhea and flora destruction", "E": "Osmotic demyelination"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to the emergency department because of increasing shortness of breath for 2 days. He is at 30th percentile for height and at 25th percentile for weight. His temperature is 37.1°C (98.8°F), pulse is 144/min, respirations are 40/min, and blood pressure is 80/44 mm Hg. Bilateral crackles are heard at the lung bases. A grade 3/6 holosystolic murmur is heard over the left lower sternal border. A grade 2/6 mid-diastolic murmur is heard best in the left fourth intercostal space. Without treatment, this patient is at risk of developing which of the following?", "answer": "Polycythemia", "options": {"A": "Cerebral aneurysm", "B": "Polycythemia", "C": "Secondary hypertension", "D": "Thrombocytosis", "E": "Myocardial ischemia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 33-year-old man presents to the emergency room for diarrhea. He states it is profuse and watery and has not been improving over the past week. He is generally healthy; however, he was recently hospitalized during spring break and treated for alcohol intoxication and an aspiration pneumonia. While on spring break, the patient also went camping and admits eating undercooked chicken and drinking from mountain streams. His temperature is 100.5°F (38.1°C), blood pressure is 111/74 mmHg, pulse is 110/min, respirations are 16/min, and oxygen saturation is 98% on room air. Physical exam is notable for a fatigued appearing man. His abdomen is non-tender. Which of the following is the best management of this patient?", "answer": "Vancomycin", "options": {"A": "Ciprofloxacin", "B": "Ciprofloxacin and metronidazole", "C": "Metronidazole", "D": "No treatment indicated", "E": "Vancomycin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old woman, gravida 1, para 0, at 30 weeks' gestation is brought to the emergency department because of progressive upper abdominal pain for the past hour. The patient vomited once on her way to the hospital. She states that she initially had dull stomach pain about 6 hours ago, but now the pain is located in the upper abdomen and is more severe. There is no personal or family history of serious illness. She is sexually active with her husband. She does not smoke or drink alcohol. Medications include folic acid and a multivitamin. Her temperature is 38.5°C (101.3°F), pulse is 100/min, and blood pressure is 130/80 mm Hg. Physical examination shows right upper quadrant tenderness. The remainder of the examination shows no abnormalities. Laboratory studies show a leukocyte count of 12,000/mm3. Urinalysis shows mild pyuria. Which of the following is the most likely diagnosis?", "answer": "Appendicitis", "options": {"A": "HELLP syndrome", "B": "Nephrolithiasis", "C": "Acute cholangitis", "D": "Appendicitis", "E": "Pyelonephritis\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year-old female is given omalizumab for the treatment of bronchial asthma. Omalizumab treats asthma through which mechanism?", "answer": "Inhibition of IgE binding to mast cells", "options": {"A": "Inhibition of IgE binding to mast cells", "B": "Binding to nuclear receptors", "C": "Inhibition of leukotriene binding to receptor", "D": "Inhibition of phosphodiesterase breakdown of cAMP", "E": "Mediating type IV hypersensitivity reaction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old man seeks evaluation at an urgent care clinic with a complaint of palpitations for the past few hours. He denies any chest pain, shortness of breath, or sweating. He is anxious and appears worried. His medical history is unremarkable with the exception of mild bronchial asthma. He only uses medications during an asthma attack and has not used medications since last week. He is a former smoker and drinks a couple of beers on weekends. His heart rate is 146/min, respiratory rate is 16/min, temperature is 37.6°C (99.68°F), and blood pressure is 120/80 mm Hg. The physical examination is unremarkable, and an electrocardiogram is ordered. Which of the following groups of drugs should be given to treat his symptoms?", "answer": "Selective β1-receptor antagonist", "options": {"A": "α1-receptor antagonist", "B": "Selective β1-receptor antagonist", "C": "Non-selective β-receptor antagonist", "D": "α-receptor agonist", "E": "β-receptor agonist"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old female college student is brought back into the university clinic for acting uncharacteristically. The patient presented to the same clinic 6 weeks ago with complaints of depressed mood, insomnia, and weightloss. She had been feeling guilty for wasting her parent’s money by doing so poorly at the university. She felt drained for at least 2 weeks before presenting to the clinic for the first time. She was placed on an antidepressant and was improving but now presents with elevated mood. She is more talkative with a flight of ideas and is easily distractible. Which of the following statements is most likely true regarding this patient’s condition?", "answer": "Her diagnosis of unipolar depression is incorrect.", "options": {"A": "Her diagnosis of unipolar depression is incorrect.", "B": "Her new symptoms need to last at least 7 days.", "C": "The patient may have a history of mania.", "D": "The patient may have psychotic features.", "E": "Antidepressants are inappropriate."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 13-year-old boy has been suspended 5 times this year for arguing with teachers. He has presented a pattern of negativism and hostility that has lasted for about 8 months. When asked about the suspensions, he admits that he loses his temper easily and often blames the principal for not being fair to him. He usually finds an argument before finishing his homework. At home, he goes out of his way to annoy his siblings. He gets furious if his legal guardian finds out about it and confiscates his smartphone. Which of the following is an additional behavior characteristic of this patient’s most likely diagnosis?", "answer": "Hostile and disobedient behavior towards authority", "options": {"A": "Destruction of property and theft", "B": "Hostile and disobedient behavior towards authority", "C": "Killing and/or harming small animals", "D": "Physical aggression", "E": "Violating the rights of others"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old woman patient presents to her family physician with recurrent retrosternal chest pain. She has had similar episodes for the past 7 months along with difficulty swallowing solid as well as liquid food. She recently completed an 8-week course of a proton pump inhibitor, but she is still bothered by the feeling that food gets stuck down her 'food pipe'. Her pain is not related to exertion. She denies any history of acid reflux disease. Her blood pressure is 125/81 mm Hg, respirations are 21/min, pulse is 78/min, and temperature is 36.7°C (98.1°F). She currently does not have pain. A barium swallow X-ray image is normal. Which of the following test would aid in the diagnosis of this patient's condition?", "answer": "Manometry", "options": {"A": "Electrocardiogram", "B": "Upper GI endoscopy", "C": "Manometry", "D": "Additional therapy with proton pump inhibitors", "E": "Injection of botulinum toxin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 49-year-old sexually active woman presents with dysuria and urinary frequency. She denies any previous urinary tract infections (UTIs), but she says that her mother has had frequent UTIs. Her medical history includes type 2 diabetes mellitus, hypertension, cervical cancer, and hypercholesterolemia. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and denies any illicit drug use. Her vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 17/min. On physical examination, her lung sounds are clear. She has a grade 2/6 holosystolic murmur heard best over the left upper sternal border. She also has tenderness in the suprapubic area. A urinalysis shows the presence of numerous leukocytes, leukocyte esterase, and nitrites. Which of the following factors would not classify a UTI as complicated?", "answer": "The causative organism is Pseudomonas aeruginosa", "options": {"A": "The patient has diabetes", "B": "The causative organism is Candida albicans", "C": "The causative organism is Pseudomonas aeruginosa", "D": "The patient has an indwelling catheter", "E": "The patient has nephrolithiasis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old woman with a history of nephrolithiasis presents with fever and acute-onset right flank pain. The patient says that 2 days ago she developed sudden-onset right flank pain and nausea which has progressively worsened. She describes the pain as severe, colicky, localized to the right flank, and radiating to the groin. This morning she woke with a fever and foul-smelling urine. She has no significant past medical history. Vital signs are temperature 40.0°C (104.0°F), blood pressure 110/70 mm Hg, pulse 92/min, and respiratory rate 21/min. Physical examination shows severe right costovertebral angle tenderness. Her laboratory findings are significant for the following:\nWBC 12,500/mm3\nRBC 4.20 x 106/mm3\nHematocrit 41.5%\nHemoglobin 14.0 g/dL\nPlatelet count 225,000/mm3\nUrinalysis:\nColor Dark yellow\nClarity Clarity Turbid\npH 5.9\nSpecific gravity 1.026\nGlucose None\nKetones None\nNitrites Positive\nLeukocyte esterase Positive\nBilirubin Negative\nUrobilirubin 0.6 mg/dL\nProtein Trace\nRBC 325/hpf\nWBC 8,200/hpf\nBacteria Many\nA non-contrast CT of the abdomen and pelvis shows an obstructing 7-mm diameter stone lodged at the ureteropelvic junction. There is also evidence of hydronephrosis of the right kidney. Which of the following is the best course of treatment for this patient?", "answer": "Admit to hospital for percutaneous nephrostomy and IV antibiotics", "options": {"A": "Discharge home with oral antibiotics", "B": "Administer hydrochlorothiazide", "C": "Admit to hospital for IV antibiotics", "D": "Administer potassium citrate", "E": "Admit to hospital for percutaneous nephrostomy and IV antibiotics"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An investigator is developing a new vaccine. After injecting the agent, the immune response is recorded by measuring vaccine-specific antibodies at subsequent timed intervals. To induce the maximum immunogenic response, this vaccine should have which of the following properties?", "answer": "Weakened live microorganisms", "options": {"A": "Foreign intact polysaccharide bound to protein", "B": "Chemically inactivated microorganism", "C": "Foreign intact polysaccharide", "D": "Foreign denaturated protein", "E": "Weakened live microorganisms"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old woman with a seizure disorder comes to the physician because of fever, fatigue, and a productive cough with foul-smelling sputum for 2 weeks. Her temperature is 38.3°C (100.9°F). Physical examination shows dullness to percussion over the right lung fields. An x-ray of the chest shows a cavitary infiltrate with an air-fluid level in the right lower lobe of the lung. Cultures of an aspirate of the infiltrate grow Peptostreptococcus and Prevotella species. Which of the following is the most likely predisposing factor for this patient's condition?", "answer": "Periodontal infection", "options": {"A": "Recent hospitalization", "B": "Intravenous drug use", "C": "Crowded housing situation", "D": "Periodontal infection", "E": "Contaminated air conditioning system"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man presents to the clinic for his annual health check-up. He currently complains of fatigue for the past few months. He has no significant past medical history. He admits to being sexually active with men and also is an intravenous drug user. He has never received a hepatitis B vaccine. His blood pressure is 122/98 mm Hg, the respiratory rate is 16/min, the pulse is 68/min, and the temperature is 37.0°C (98.6°F). On physical examination, he appears fatigued and unkempt. His tongue and buccal mucosa appear moist and without ulcerations or lesions. There are no murmurs or gallops on cardiac auscultation. His lungs are clear bilaterally. No lesions are present on the surface of the skin nor skin discoloration. The physician proceeds to order a hepatitis B panel to assess the patient’s serologic status:\nHBV DNA positive\nHBsAg negative\nHBeAg  negative\nHBsAb negative\nHBcAb positive\nHBeAb negative\nWhich of the following disease states is the patient exhibiting?", "answer": "Convalescent (window) period", "options": {"A": "Acute infection", "B": "Chronic infection", "C": "Immune from vaccine", "D": "Immune from natural infection", "E": "Convalescent (window) period"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old construction worker presents to his primary care physician with a painful and swollen wrist joint. A joint aspiration shows crystals, which are shown in the accompanying picture. Which of the following is the most likely diagnosis?", "answer": "Monosodium urate crystals", "options": {"A": "Monosodium urate crystals", "B": "Hydroxyapatite crystals", "C": "Calcium pyrophosphate crystals", "D": "Cholesterol crystals", "E": "Charcot Leyden crystals"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old man presents with epigastric pain over the last 6 months. He says the pain gets worse with food, especially coffee. He also complains of excessive belching. He says he has tried omeprazole recently, but it has not helped. No significant past medical history or current medications. On physical examination, there is epigastric tenderness present on deep palpation. An upper endoscopy is performed which reveals gastric mucosa with signs of mild inflammation and a small hemorrhagic ulcer in the antrum. A gastric biopsy shows active inflammation, and the specimen stains positive with Warthin–Starry stain, revealing Helicobacter pylori. Which of the following is the next, best step in the management of this patient’s condition?", "answer": "Give amoxicillin, clarithromycin, and omeprazole", "options": {"A": "Start famotidine and erythromycin", "B": "Observation", "C": "Perform colonoscopy", "D": "Give amoxicillin, clarithromycin, and omeprazole", "E": "Give amoxicillin, erythromycin and omeprazole"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old man comes to the emergency room with difficulty in breathing. He was diagnosed with severe obstructive lung disease a few years back. He uses his medication but often has to come to the emergency room for intravenous therapy to help him breathe. He was a smoker for 40 years smoking two packs of cigarettes every day. Which of the following best represents the expected changes in his ventilation, perfusion and V/Q ratio?", "answer": "Low ventilation, normal perfusion and low V/Q ratio", "options": {"A": "Higher ventilation and perfusion with lower V/Q ratio", "B": "Low ventilation, normal perfusion and low V/Q ratio", "C": "Lower ventilation and perfusion, but higher V/Q ratio", "D": "Medium ventilation and perfusion, V/Q that equals 0.8", "E": "Normal ventilation, low or nonexistent perfusion and infinite V/Q ratio"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 67-year-old African American male presents to the emergency room complaining of nausea and right flank pain. He reports that these symptoms have worsened over the past two days. His past medical history is notable for congestive heart failure, hypertension, hyperlipidemia, and diabetes mellitus. He currently takes aspirin, losartan, metoprolol, atorvastatin, hydrochlorothiazide, furosemide, and metformin. He is allergic to fluoroquinolones. His temperature is 102.9°F (39.4°C), blood pressure is 100/50 mmHg, pulse is 120/min, and respirations are 28/min. On exam, he demonstrates right costovertebral angle tenderness. Urinalysis reveals 30 WBCs/hpf and positive leukocyte esterase. He is admitted and started on a broad-spectrum combination intravenous antibiotic. He recovers well and is discharged with plans to follow up in 2 weeks. At his follow-up, he reports that he has developed transient visual blurring whenever he turns his head to the right or left. He also reports that he has fallen at home multiple times. What is the mechanism of action of the drug that is most likely responsible for this patient’s current symptoms?", "answer": "Inhibition of ribosomal 30S subunit", "options": {"A": "Inhibition of ribosomal 30S subunit", "B": "Inhibition of ribosomal 50S subunit", "C": "Inhibition of dihydropteroate synthase", "D": "Inhibition of transpeptidase", "E": "Inhibition of DNA gyrase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old woman comes to the physician because of a 1-week history of shortness of breath and dry cough. Eight weeks ago, she received a lung transplant from an unrelated donor. Current medications include prednisone, cyclosporine, and azathioprine. Her temperature is 37.8°C (100.1°F). Physical examination is unremarkable other than a well-healed surgical scar. Pulmonary function tests show a decline in FEV1 and FVC compared to values from several weeks ago. Histological examination of a lung biopsy specimen shows perivascular and interstitial lymphocytic infiltrates with bronchiolar inflammation. This patient's condition is most likely caused by T cell sensitization against which of the following?", "answer": "Donor MHC class II antigen", "options": {"A": "Donor ABO antigen", "B": "Donor MHC class II antigen", "C": "Recipient MHC class I antigen", "D": "Streptococcal C polysaccharide antigen", "E": "CMV glycoprotein B antigen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is developing a new intravenous medication that acts as a selective agonist at β-2 receptors. In addition to causing bronchodilation, this drug is most likely to have which of the following effects?", "answer": "Bladder detrusor relaxation", "options": {"A": "Decreased skeletal glycogenolysis", "B": "Increased gastrointestinal peristalsis", "C": "Peripheral vasoconstriction", "D": "Bladder detrusor relaxation", "E": "Increased uterine tone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old female with a history of systemic lupus erythematous (SLE) has a 3-year history of daily prednisone (20 mg) use. Due to long-term prednisone use, she is at increased risk for which of the following?", "answer": "Pathologic fractures", "options": {"A": "Hair loss", "B": "Weight loss", "C": "Pancreatic insufficiency", "D": "Systolic hypertension", "E": "Pathologic fractures"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old girl comes to the physician for an annual health maintenance examination. She feels well. She has no history of serious illness and her only medication is an oral contraceptive. Her mother was diagnosed with breast cancer at the age of 42 years. She is currently sexually active with 1 male partner and uses condoms inconsistently. Her immunizations are up-to-date. Her vital signs are within normal limits. Physical and pelvic examinations shows no abnormalities. An HIV test is negative. Which of the following is the most appropriate next step in management?", "answer": "Nucleic acid amplification testing", "options": {"A": "Complete blood count", "B": "Nucleic acid amplification testing", "C": "PAP smear", "D": "Rapid plasma reagin test", "E": "Herpes simplex virus 2 serology"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 74-year-old man presents to the emergency department with sudden-onset abdominal pain that is most painful around the umbilicus. The pain began 16 hours ago and has no association with meals. He has not been vomiting, but he has had several episodes of bloody loose bowel movements. He was hospitalized 1 week ago for an acute myocardial infarction. He has had diabetes mellitus for 35 years and hypertension for 20 years. He has smoked 15–20 cigarettes per day for the past 40 years. His temperature is 36.9°C (98.42°F), blood pressure is 95/65 mm Hg, and pulse is 95/min. On physical examination, the patient is in severe pain, there is mild periumbilical tenderness, and a bruit is heard over the epigastric area. Which of the following is the definitive test to assess the patient condition?", "answer": "Mesenteric angiography", "options": {"A": "Mesenteric angiography", "B": "CT scanning", "C": "Plain abdominal X-rays", "D": "Colonoscopy", "E": "Complete blood count"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 24-year-old male is brought to the emergency department because of fevers, congestion, and chest pain for 3 days. The chest pain is exacerbated by deep inspiration. He takes no medications. His temperature is 37.5°C (99.5°F), blood pressure is 118/75 mm Hg, pulse is 130/min, and respirations are 12/min. He appears weak and lethargic. Cardiac examination shows a scratchy sound best heard along the left sternal border when the patient leans forward. There are crackles in both lung bases. Examination of the lower extremities shows pitting edema. Results of a rapid influenza test are negative. EKG shows diffuse ST-elevations with depressed PR interval. An echocardiogram shows left ventricular chamber enlargement with contractile dysfunction. Infection with which of the following pathogens is the most likely cause of this patient's symptoms?", "answer": "Picornavirus", "options": {"A": "Togavirus", "B": "Paramyxovirus", "C": "Flavivirus", "D": "Orthomyxovirus", "E": "Picornavirus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 56-year-old man comes to the physician because of chest pain and shortness of breath for 3 days. The pain is present at rest and worsens with deep inspiration. His temperature is 37.2°C (99°F), pulse is 102/min, respirations are 23/min, and blood pressure is 135/88 mm Hg. Examination shows decreased breath sounds at the left lower lobe. Laboratory studies show:\nHematocrit 42%\nLeukocyte count 6,500/μL\nSerum\nFasting glucose 90 mg/dL\nLactate dehydrogenase 75 U/L\nTotal protein 7.2 g/dL\nAn x-ray of the chest shows a small left-sided pleural effusion but no other abnormalities. A diagnostic thoracentesis is performed and 100 mL of bloody fluid are aspirated from the left pleural space. Pleural fluid analysis shows a lactate dehydrogenase of 65 U/L and a total protein of 5.1 g/dL. Pleural fluid cytology shows normal cell morphology. Further evaluation of this patient is most likely to show a history of which of the following?\"", "answer": "Prolonged immobilization", "options": {"A": "Oropharyngeal dysphagia", "B": "Infliximab use", "C": "Prolonged immobilization", "D": "Congestive heart failure", "E": "Asbestos exposure"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A concerned father brings his 2 year-old son to the clinic for evaluation. In the past 24 hours, the child has had multiple episodes of painless bloody stools. On physical examination, the child's vital signs are within normal limits. There is mild generalized discomfort on palpation of the abdomen but no rebound or guarding. A technetium-99m (99mTc) pertechnetate scan indicates increased activity in two locations within the abdomen. Cells originating in which organ account for the increased radionucleotide activity?", "answer": "Stomach", "options": {"A": "Stomach", "B": "Pancreas", "C": "Small intestine", "D": "Gallbladder", "E": "Liver"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 5-year-old boy is brought to the emergency department because of abdominal pain and vomiting for 6 hours. His mother immediately brought him after noticing that he had gotten into the medicine cabinet. The mother is 5 months' pregnant. He appears uncomfortable. His temperature is 37.2°C (99°F), pulse is 133/min and blood pressure is 80/50 mm Hg. Examination shows diffuse abdominal tenderness; there is no guarding or rigidity. Digital rectal examination shows dark-colored stools. Laboratory studies show:\nHemoglobin 13.2 g/dL\nLeukocyte count 14,100/mm3\nSerum\nNa+ 136 mEq/L\nK+ 3.3 mEq/L\nCl- 105 mEq/L\nUrea nitrogen 26 mg/dL\nGlucose 98 mg/dL\nCreatinine 1.1 mg/dL\nArterial blood gas analysis on room air shows:\npH 7.31\npCO2 32 mm Hg\nHCO3- 16 mEq/L\nIntravenous fluids are administered. Which of the following is the most appropriate next step in management?\"", "answer": "Deferoxamine", "options": {"A": "Syrup of ipecac", "B": "Deferoxamine", "C": "Sodium bicarbonate", "D": "Activated charcoal", "E": "Calcium EDTA"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man is brought to the emergency department by a social worker from the homeless shelter. The man was acting strangely and then found unresponsive in his room. The social worker says she noticed many empty pill bottles near his bed. The patient has a past medical history of multiple hospital admissions for acute pancreatitis, dehydration, and suicide attempts. He is not currently taking any medications and is a known IV drug user. His temperature is 99.2°F (37.3°C), blood pressure is 107/48 mmHg, pulse is 140/min, respirations are 22/min, and oxygen saturation is 98% on room air. Physical exam is notable for a man with a Glasgow coma scale of 6. Laboratory values are ordered as seen below.\n\nHemoglobin: 10 g/dL\nHematocrit: 30%\nLeukocyte count: 5,500/mm^3 with normal differential\nPlatelet count: 147,000/mm^3\n\nSerum:\nAlbumin: 1.9 g/dL\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 29 mg/dL\nGlucose: 65 mg/dL\nCreatinine: 1.5 mg/dL\nCa2+: 10.2 mg/dL\nProthrombin time: 27 seconds\nPartial thromboplastin time: 67 seconds\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following is the most effective therapy for this patient's underlying pathology?", "answer": "Liver transplant", "options": {"A": "Colloid-containing fluids", "B": "Factor 2, 7, 9, and 10 concentrate", "C": "Fresh frozen plasma", "D": "Liver transplant", "E": "Supportive therapy, thiamine, dextrose, naloxone, and NPO"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 75-year-old man presents to the physician because of bloody urine, which has occurred several times over the past month. He has no dysuria, flank pain, nausea, or vomiting. He has no history of serious illness and takes no medications. He is a 40-pack-year smoker. The vital signs are within normal limits. Physical exam shows no abnormalities except generalized lung wheezing. The laboratory test results are as follows:\nUrine\nBlood 3+\nRBC > 100/hpf\nWBC 1–2/hpf\nRBC casts Negative\nBacteria Not seen\nWhich of the following is the most appropriate diagnostic study at this time?", "answer": "Cystoscopy", "options": {"A": "Chest X-ray", "B": "Computed tomography (CT) urogram", "C": "Cystoscopy", "D": "Intravenous (IV) pyelography", "E": "Ureteroscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman with a past medical history significant for cardiac palpitations and hypothyroidism presents with cyclical lower abdominal pain and pelvic pain. Upon further questioning, she endorses difficulty conceiving over the last 12 months. On a review of systems, she endorses occasional pain with intercourse, which has become more frequent over the last 6 months. On physical examination, her heart and lungs are clear to auscultation, her abdomen has mild tenderness in the lower quadrants, and she shows normal range of motion in her extremities. Given the patient’s desire to conceive, what is the most definitive treatment for her presumed condition?", "answer": "Laparoscopy and lesion ablation", "options": {"A": "Oral contraceptive pills (OCPs)", "B": "NSAIDS", "C": "Leuprolide", "D": "Total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAH-BSO)", "E": "Laparoscopy and lesion ablation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 10-year-old girl is brought to the neurologist for management of recently diagnosed seizures. Based on her clinical presentation, the neurologist decides to start a medication that works by blocking thalamic T-type calcium channels. Her parents are cautioned that the medication has a number of side effects including itching, headache, and GI distress. Specifically, they are warned to stop the medication immediately and seek medical attention if they notice skin bullae or sloughing. Which of the following conditions is most likely being treated in this patient?", "answer": "Absence seizures", "options": {"A": "Absence seizures", "B": "Complex seizures", "C": "Simple seizures", "D": "Status epilepticus", "E": "Tonic-clonic seizures"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A scientist performed an experiment to produce hybrid viruses by mixing two different serotypes of influenza virus, H1N1 and H2N2, in a respiratory epithelium cell line. Several days later, the scientist collected the media and analyzed the viral progeny. She found the following serotypes of virus: H1N1, H2N2, H1N2, and H2N1. Which of the following terms best explains the appearance of new serotypes?", "answer": "Reassortment", "options": {"A": "Recombination", "B": "Reassortment", "C": "Complementation", "D": "Phenotypic mixing", "E": "Transformation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old woman comes to the physician because of a 3-month history of progressive weakness. She has no history of serious illness and takes no medications. Her vital signs are within normal limits. Physical examination shows a violaceous rash over her eyelids and flat-topped erythematous papules over the dorsal surface of interphalangeal joints. Muscle strength is 4/5 at the shoulders and hips but normal elsewhere. This patient is at greatest risk for which of the following conditions?", "answer": "Ovarian adenocarcinoma", "options": {"A": "Pheochromocytoma", "B": "Hodgkin lymphoma", "C": "Renal clear cell carcinoma", "D": "Oat cell lung cancer", "E": "Ovarian adenocarcinoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old man comes to the physician because of a 5-month history of progressive lethargy, shortness of breath, and difficulty concentrating. His friends have told him that he appears pale. He has smoked half a pack of cigarettes daily for the past 20 years. Neurological examination shows reduced sensation to light touch and pinprick in the toes bilaterally. Laboratory studies show:\nHemoglobin 8.2 g/dL\nMean corpuscular volume 108 μm3\nSerum\nVitamin B12 (cyanocobalamin) 51 ng/L (N = 170–900)\nFolic acid 13 ng/mL (N = 5.4–18)\nAn oral dose of radiolabeled vitamin B12 is administered, followed by an intramuscular injection of nonradioactive vitamin B12. A 24-hour urine sample is collected and urine vitamin B12 levels are unchanged. The procedure is repeated with the addition of oral intrinsic factor, and 24-hour urine vitamin B12 levels increase. This patient's findings indicate an increased risk for which of the following conditions?\"", "answer": "Gastric carcinoma", "options": {"A": "Colorectal carcinoma", "B": "Gastric carcinoma", "C": "De Quervain thyroiditis", "D": "Type 2 diabetes mellitus", "E": "Celiac disease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man comes to the physician for the evaluation of an 8-week history of blood in his stool. Two months ago, he had an episode of bronchitis and was treated with amoxicillin. Since then, he has noticed blood in his stool and on the toilet paper occasionally. The patient has had intermittent constipation for the past 5 years. Six months ago, he had severe left lower quadrant pain and fever that resolved with antibiotic therapy. He underwent a colonoscopy 3 years ago, which did not show any evidence of malignancy. He takes levothyroxine for hypothyroidism. He had smoked one pack of cigarettes daily for 45 years, but quit smoking 10 years ago. He drinks one glass of red wine every night. He appears pale. He is 180 cm (5 ft 11 in) tall and weighs 98 kg (216 lb); BMI is 32 kg/m2. His temperature is 36°C (96.8°F), pulse is 85/min, and blood pressure is 135/80 mm Hg. Physical examination shows pale conjunctivae. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender with no organomegaly. Digital rectal examination shows no masses. Test of the stool for occult blood is positive. Laboratory studies show:\nHemoglobin 11 g/dL\nMean corpuscular volume 76 μm3\nRed cell distribution width 17% (N = 13–15)\nLeukocyte count 5,000/mm3\nWhich of the following is the most likely diagnosis?\"", "answer": "Diverticulosis", "options": {"A": "Colorectal carcinoma", "B": "Diverticulosis", "C": "Ischemic colitis", "D": "Hemorrhoids", "E": "Pseudomembranous colitis\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An overweight 57-year-old woman comes to her primary care physician for a routine checkup. She has no current complaints and takes no medications. Her mother and brother have type 2 diabetes mellitus and hypertension. Vital signs show a blood pressure of 145/95 mmHg, temperature of 37°C (98.6°F), and a pulse of 85/minute. Her lab results are shown:\nFasting blood glucose 158 mg/dL\n HbA1c  8.6%\n Low-density lipoprotein  210 mg/dL\n High-density lipoprotein  27 mg/dL\n Triglycerides  300 mg/dL\nWhich of the following tests is recommended for this patient?", "answer": "Digital fundus photography now, then yearly follow-up", "options": {"A": "Albumin-to-creatinine ratio after 5 years, then yearly follow-up", "B": "Monofilament test after 5 years, then yearly follow-up", "C": "Fasting lipid profile every 5 years", "D": "Digital fundus photography after 5 years, then yearly follow-up", "E": "Digital fundus photography now, then yearly follow-up"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old man comes to the physician because of a 4-month history of unintentional weight gain, fatigue, and decreased sexual desire. There is no personal or family history of serious illness. His blood pressure is 149/88 mm Hg. Physical examination shows central obesity and abdominal striae. He has a prominent soft tissue bulge at the dorsum of his neck. Laboratory studies show a 24-hour urinary free cortisol of 200 μg (N < 50) and a morning serum ACTH of 1 pg/mL (N = 7–50). Which of the following tests is most likely to confirm the underlying etiology of this patient's symptoms?", "answer": "Abdominal CT", "options": {"A": "CRH stimulation test", "B": "ACTH stimulation test", "C": "Chest CT", "D": "Abdominal CT", "E": "Brain MRI"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old woman comes to the physician because of worsening shortness of breath for the past two weeks. Physical examination shows decreased breath sounds at both lung bases. The abdomen is distended and there is shifting dullness with a positive fluid wave. Ultrasound of the abdomen shows a large collection of peritoneal fluid and a hypoechoic mass involving the left ovary. Microscopic examination of a biopsy specimen from the ovarian mass shows clusters of spindle-shaped cells. Which of the following is the most likely diagnosis?", "answer": "Ovarian fibroma", "options": {"A": "Serous cystadenoma", "B": "Endometrioma", "C": "Ovarian thecoma", "D": "Dermoid cyst", "E": "Ovarian fibroma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 39-year-old woman presents to her primary care physician because she has been experiencing intermittent abdominal pain for the last 2 weeks. She says that the pain is squeezing in nature, is located in the right upper quadrant, and is particularly severe after eating a meal. After a diagnosis is made, the patient asks why the pain gets worse after eating. The physician explains that food is detected by the gastrointestinal tract through numerous receptors and that this information is transmitted to other parts of the body to cause compensatory changes. The neurons responsible for transmitting this information are most likely located in a layer of the intestine that has which of the following characteristics?", "answer": "Contains large blood vessels and large lymphatic vessels", "options": {"A": "Connective tissue that envelops the other layers", "B": "Contains cells that primarily absorb nutrients", "C": "Contains large blood vessels and large lymphatic vessels", "D": "Contracts to generate peristaltic waves", "E": "Contracts to generate local movement in mucosa"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 41-year-old man comes to the physician because of a 7-month history of sleep disturbances, restlessness, and difficulty acquiring erections. He started a new job as a project coordinator 8 months ago. He has difficulty falling asleep and lies awake worrying about his family, next day's meetings, and finances. He can no longer concentrate on his tasks at work. He feels tense most days and avoids socializing with his friends. He worries that he has an underlying medical condition that is causing his symptoms. Previous diagnostic evaluations were unremarkable. He has a history of drinking alcohol excessively during his early 20s, but he has not consumed alcohol for the past 10 years. He appears anxious. Physical examination shows no abnormalities. In addition to psychotherapy, treatment with which of the following drugs is most appropriate in this patient?", "answer": "Buspirone", "options": {"A": "Escitalopram", "B": "Propranolol", "C": "Clonazepam", "D": "Amitriptyline", "E": "Buspirone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A new study shows a significant association between patients with a BMI >40 and a diagnosis of diabetes (odds ratio: 7.37; 95% CI 6.39-8.50) compared to non-diabetic patients. Which of the following hypothetical studies most likely yielded these results.", "answer": "A study consisting of 500 patients with diabetes and 500 patients without diabetes comparing BMI of subjects in both groups", "options": {"A": "A study consisting of 1000 non-diabetic subjects; 500 patients with a BMI > 40 and 500 patients with normal BMI, followed for diagnosis of diabetes over their life time", "B": "A study consisting of 500 patients with diabetes and 500 patients without diabetes comparing BMI of subjects in both groups", "C": "A study consisting of 1000 genetically similar mice; 500 randomized to diet to maintain normal weight and 500 randomized to high caloric intake with the outcome of diabetes rates in both groups after 1 year", "D": "A study of 1000 patients with BMI > 40 with diabetes; 500 randomized to inpatient diet and exercise with goal BMI <25, and 500 randomized to no treatment with an outcome of glycemic control without medication after 1 year", "E": "A study of 1000 patients comparing rates of diabetes diagnoses and BMIs of diabetic and non-diabetic patients"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 14-year-old girl is brought to the physician because of a 1-week history of fever, malaise, and chest pain. She describes the pain as 6 out of 10 in intensity and that it is more severe if she takes a deep breath. The pain is centrally located in the chest and does not radiate. Three weeks ago, she had a sore throat that resolved without treatment. She has no personal history of serious illness. She appears ill. Her temperature is 38.7°C (101.7°F). Examination shows several subcutaneous nodules on the elbows and wrist bilaterally. Breath sounds are normal. A soft early systolic murmur is heard best at the apex in the left lateral position. Abdominal examination is unremarkable. Laboratory studies show:\nHemoglobin 12.6 g/dL\nLeukocyte count 12,300/mm3\nPlatelet count 230,000/mm3\nErythrocyte sedimentation rate 40 mm/hr\nSerum\nAntistreptolysin O titer 327 U/mL (N < 200 U/mL)\nShe is treated with aspirin and penicillin and her symptoms resolve. An echocardiography of the heart done 14 days later shows no abnormalities. Which of the following is the most appropriate next step in management?\"", "answer": "Intramuscular benzathine penicillin every 4 weeks for 10 years", "options": {"A": "Intramuscular benzathine penicillin every 4 weeks for 10 years", "B": "Low-dose prednisone therapy for a month", "C": "Intramuscular benzathine penicillin every 4 weeks until the age of 40", "D": "Intramuscular benzathine penicillin every 4 weeks until the age of 21", "E": "Intramuscular benzathine penicillin every 4 weeks for 5 years"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 58-year-old woman presents to her primary care physician for a wellness checkup. She recently had a DEXA scan that placed her at 2 standard deviations below the mean for bone density. She is following up today to discuss her results. The patient has a past medical history of asthma, breast cancer, COPD, anxiety, irritable bowel syndrome, endometrial cancer, and depression. She is currently taking clonazepam, albuterol, and fluoxetine. Her temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 95% on room air. The patient is treated appropriately and sent home. She returns 1 month later for a follow up visit. She has been taking her medications as prescribed. She endorses episodes of feeling febrile/warm which resolve shortly thereafter. Otherwise she is doing well. Which of the following is true of the medication she was most likely started on?", "answer": "Estrogen receptor antagonist in the uterus", "options": {"A": "Estrogen receptor agonist in the uterus", "B": "Estrogen receptor antagonist in the uterus", "C": "Induces osteoclast apoptosis", "D": "Mineral replacement", "E": "Parathyroid hormone analogue"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old man with a history notable for alpha-thalassemia now presents to an urgent care clinic with complaints of increased thirst and urinary frequency. The physical exam is unremarkable, although there is a bronze discoloration of his skin. The laboratory analysis reveals a fasting blood glucose of 192 mg/dL, and a HbA1c of 8.7. Given the following options, what is the best treatment for the patient’s underlying disease?", "answer": "Recurrent phlebotomy", "options": {"A": "Metformin", "B": "Basal insulin", "C": "Basal and bolus insulin", "D": "Recurrent phlebotomy", "E": "Deferoxamine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old woman presents with convulsions. The patient’s brother says that he found her like that an hour ago and immediately called an ambulance. He also says that she has been extremely distraught and receiving supportive care from a social worker following a sexual assault by a coworker a few days ago. He says that the patient has no history of seizures. She has no significant past medical history and takes no medications. The patient’s vital signs include: temperature 37.0°C (98.6°F), pulse 101/min, blood pressure 135/99 mm Hg, and respiratory rate 25/min. On physical examination, the patient is rolling from side to side, arrhythmically thrashing around, and muttering strangely. Her eyes are closed, and there is resistance to opening them. Which of the following is the most likely diagnosis in this patient?", "answer": "Conversion disorder", "options": {"A": "Somatization disorder", "B": "Somatoform pain disorder", "C": "Conversion disorder", "D": "Hypochondriasis", "E": "Body dysmorphic disorder"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old man comes to the physician because of difficulty walking for 2 months. He has been falling to his left side when he walks more than a few feet. His speech has also changed in the past few months, and he now pauses between each syllable. He has never had similar symptoms before. He has hypertension and cirrhosis as a result of alcoholic liver disease. He does not smoke and he no longer drinks alcohol. His current medications include lisinopril and hydrochlorothiazide daily. His vital signs are within normal limits. Physical examination shows discrete scleral icterus and jaundice. There is ascites and gynecomastia present. Neurological examination shows nystagmus with fast beats toward the left. He has dysmetria and tremor when performing left-sided finger-nose-finger testing, and dysdiadochokinesia with rapid alternating movements. He has a wide-based gait and a pronator drift of the left arm. He has full range of motion in his arms and legs without rigidity. He has full muscle strength, and sensation to light touch is intact. Further evaluation is most likely to show which of the following?", "answer": "Left-sided cerebellar tumor", "options": {"A": "Increased number of trinucleotide CAG repeats", "B": "Decreased serum thiamine levels", "C": "Periventricular plaques", "D": "Left-sided cerebellar tumor", "E": "Left-sided posterior capsular infarct"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old man comes to the physician with a 1-week history of sharp, substernal chest pain that is worse with inspiration and relieved with leaning forward. He has also had nausea and myalgias. His father has coronary artery disease. His temperature is 37.3°C (99.1°F), pulse is 110/min, and blood pressure is 130/84 mm Hg. Cardiac examination shows a high-pitched rubbing sound between S1 and S2 that is best heard at the left sternal border. An ECG shows depressed PR interval and diffuse ST elevations. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Acute viral infection", "options": {"A": "Dressler syndrome", "B": "Acute myocardial infarction", "C": "Mycobacterium tuberculosis infection", "D": "Systemic lupus erythematosus", "E": "Acute viral infection"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 73-year-old man presents to a dermatology clinic after his family physician finds an ulcerated plaque on the dorsal surface of his nose. This lesion has changed in size and form and has bled on multiple occasions even after the patient adopted sun-protection measures. The patient’s medical history is relevant for cigarette smoking and hypertension. Physical examination reveals a poorly defined, erythematous, ulcerated plaque on the surface of the nose (see image). The lesion is diagnosed as squamous cell carcinoma, and the patient undergoes standard excision. However, the pathology report indicates an incomplete excision. Which of the following should be the next step in the management of this case?", "answer": "Mohs surgery", "options": {"A": "Mohs surgery", "B": "Photodynamic therapy", "C": "Cryotherapy", "D": "Radiation therapy", "E": "Imiquimod"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old woman presents to your office after three days of fever and productive cough. She is taking Tylenol for her fever and her last dose was yesterday morning. She reports reddish brown sputum. She has a history of hypertension and hypercholesterolemia for which she takes lisinopril and a statin. She has never smoked and drinks 1-2 glasses of wine a week. She recently returned from Italy and denies having any sick contacts. On physical exam, her temperature is 102.2°F (39°C), blood pressure is 130/78 mmHg, pulse is 90/min, respirations are 21/min, and pulse oximetry is 95% on room air. She has decreased breath sounds in the left lower lobe. Chest x-ray is shown. The causative organism would most likely show which of the following?", "answer": "Optochin sensitivity", "options": {"A": "Beta hemolysis", "B": "Gamma hemolysis", "C": "Optochin resistance", "D": "Optochin sensitivity", "E": "Novobiocin sensitivity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 53-year-old woman presents for a follow-up. She took some blood tests recently for her yearly physical, and her random blood sugar level was found to be 251 mg/dL. She was asked to repeat her blood sugar and come back with the new reports. At that time, her fasting blood sugar level was 130 mg/dL and the postprandial glucose level was 245 mg/dL. Her HbA1c is 8.9%. She has had occasions where she felt light-headed and felt better only after she had something to eat. Her physician starts her on a drug to help her control her sugar levels. He also advised that she should get her liver enzymes checked with a repeat HbA1c in 3 months. Which of the following is the mechanism of action of the drug that she was most likely prescribed?", "answer": "Acts as an agonist at the peroxisome proliferator-activated receptor-Ƴ.", "options": {"A": "Stimulates the release of insulin from the pancreas.", "B": "Increases the uptake of glucose and reduces peripheral insulin resistance.", "C": "Acts as an agonist at the peroxisome proliferator-activated receptor-Ƴ.", "D": "Inhibit alpha-glucosidase in the intestines.", "E": "Decreases the secretion of glucagon."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "You are conducting a study on hypertension for which you have recruited 60 African-American adults. If the biostatistician for your study informs you that the sample population of your study is approximately normal, the mean systolic blood pressure is 140 mmHg, and the standard deviation is 7 mmHg, how many participants would you expect to have a systolic blood pressure between 126 and 154 mmHg?", "answer": "57 participants", "options": {"A": "10 participants", "B": "41 participants", "C": "57 participants", "D": "68 participants", "E": "Not enough information provided."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old male is brought to the emergency room after he was found to have a blood pressure of 180/100 mm Hg during a routine health check-up with his family physician. Past medical history is insignificant and both of his parents are healthy. He currently does not take any medication. The patient’s blood pressure normalizes before the emergency department physician can evaluate him. During the physical examination, his blood pressure is 148/80 mm Hg, heart rate is 65/min, temperature is 36.8°C (98.2°F), and respirations are 14/min. He has a round face, centripetal obesity, and striae on the skin with atrophy over the abdomen and thighs. On visual field examination, he is found to have loss of vision in the lateral visual fields bilaterally  You order a low dose dexamethasone suppression test, which is positive, and you proceed to measure ACTH and obtain a high-dose dexamethasone suppression test. If this is a pituitary gland disorder, which of the following lab abnormalities is most likely present in this patient?", "answer": "Before test: ACTH high, after test: cortisol suppression", "options": {"A": "Before test: ACTH high, after test: aldosterone suppression", "B": "Before test: ACTH low, after test: cortisol elevation", "C": "Before test: ACTH high, after test: cortisol suppression", "D": "Before test: ACTH low, after test: aldosterone normalizes", "E": "Before test: ACTH high, after test: cortisol elevation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old man presents to his primary care physician for a wellness checkup. He states that he feels fatigued at times but feels near his baseline. The patient smokes 1 pack of cigarettes per day, drinks alcohol occasionally, and has a past medical history of poorly controlled diabetes. His temperature is 98.6°F (37.0°C), blood pressure is 167/108 mmHg, pulse is 80/min, respirations are 10/min, and oxygen saturation is 98% on room air. Physical exam reveals an overweight man with a ruddy complexion. Bilateral gynecomastia is noted for which the patient inquires about cosmetic surgery as a treatment. Laboratory values are ordered as seen below.\n\nHemoglobin: 14 g/dL\nHematocrit: 42%\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 185,000/mm^3\n\nSerum:\nNa+: 142 mEq/L\nCl-: 102 mEq/L\nK+: 3.2 mEq/L\nHCO3-: 31 mEq/L\nBUN: 27 mg/dL\nGlucose: 173 mg/dL\nCreatinine: 1.5 mg/dL\nCa2+: 9.8 mg/dL\n\nA CT scan demonstrates bilateral abnormal abdominal masses. Which of the following is the best next step in management?", "answer": "Eplerenone", "options": {"A": "Eplerenone", "B": "Hydrochlorothiazide", "C": "Lisinopril", "D": "Spironolactone", "E": "Surgical excision"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 39-year-old woman comes to the physician because of an 8-month history of progressive fatigue, shortness of breath, and palpitations. She has a history of recurrent episodes of joint pain and fever during childhood. She emigrated from India with her parents when she was 10 years old. Cardiac examination shows an opening snap followed by a late diastolic rumble, which is best heard at the fifth intercostal space in the left midclavicular line. This patient is at greatest risk for compression of which of the following structures?", "answer": "Esophagus", "options": {"A": "Trachea", "B": "Thoracic duct", "C": "Vagus nerve", "D": "Hemiazygos vein", "E": "Esophagus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 5-week-old male infant is rushed to the emergency department due to severe vomiting and lethargy for the past 3 days. His mother describes the vomiting as forceful and projectile and contains undigested breast milk, but she did not notice any green fluids. He has not gained much weight in the past 3 weeks and looks very thin. He has a pulse of 144/min, temperature of 37.5°C (99.5°F), and respiratory rate of 18/min. Mucous membranes are dry and the boy is lethargic. Abdominal examination reveals a palpable mass in the epigastrium that becomes more prominent after vomiting with visible peristaltic movements over the epigastrium. Barium-contrast studies show a double channel appearance of the pylorus. What is the best immediate step in the management of this patient’s condition?", "answer": "Correct electrolyte imbalances", "options": {"A": "Reassurance and observation", "B": "Pyloromyotomy", "C": "Whipple procedure", "D": "Correct electrolyte imbalances", "E": "Nasogastric tube feeding"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Thirty minutes after delivery, a 3400-g (7.5-lb) female newborn develops cyanosis of her lips and oral mucosa. She was born at 36 weeks of gestation to a 30-year-old woman, gravida 1, para 0. Apgar scores are 7 and 8 at 1 and 5 minutes, respectively. Pregnancy was complicated by polyhydramnios. The patient's temperature is 37°C (98.6°F), pulse is 144/min, respirations are 52/min, and blood pressure is 70/40 mm Hg. Examination shows foaming and drooling at the mouth. Bilateral crackles are heard at the lung bases. There is a harsh 3/6 systolic murmur along the left sternal border. The abdomen is soft and mildly distended. There is an anterior ectopic anus. Insertion of a nasogastric tube is attempted. An x-ray of the chest and abdomen is shown. Which of the following is the most likely diagnosis?", "answer": "Esophageal atresia with tracheoesophageal fistula to the distal esophageal segment", "options": {"A": "Esophageal atresia with tracheoesophageal fistula to the proximal esophageal segment", "B": "H‑type tracheoesophageal fistula without esophageal atresia", "C": "Esophageal atresia with tracheoesophageal fistula to the distal esophageal segment", "D": "Esophageal atresia with tracheoesophageal fistula to the proximal and distal esophageal segments", "E": "Esophageal atresia without tracheoesophageal fistula"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Following a gastric surgery, a 45-year-old woman complains of severe nausea and vomiting on the second post-operative day. On physical examination, her vitals are stable and examination of the abdomen reveals no significant abnormality. As she is already receiving an appropriate dosage of ondansetron, the surgeon adds metoclopramide to her treatment orders. Following addition of the drug, she experiences significant relief from nausea and vomiting. Which of the following mechanisms best explains the action of this drug?", "answer": "Inhibition of dopamine receptors in the area postrema", "options": {"A": "Enhancement of small intestinal and colonic motility by dopamine antagonism", "B": "Inhibition of dopamine receptors in the area postrema", "C": "Decreased esophageal peristaltic amplitude", "D": "Stimulation of motilin receptors in gastrointestinal smooth muscle", "E": "Inhibition of serotonin receptors on the nucleus tractus solitarius"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 19-year-old boy presents to the emergency department with difficulty breathing, which began 1 hour ago. He has had persistent bronchial asthma since 3 years of age and has been prescribed inhaled fluticasone (400 μg/day) by his pediatrician. He has not taken the preventer inhaler for the last 2 weeks and visited an old house today that had a lot of dust accumulated on the floor. On physical examination, his temperature is 36.8°C (98.4°F), the pulse is 110/min, and the respiratory rate is 24/min. There are no signs of respiratory distress, and chest auscultation reveals bilateral wheezing. Which of the following medications is most likely to provide quick relief?", "answer": "Inhaled albuterol", "options": {"A": "Inhaled albuterol", "B": "Inhaled salmeterol", "C": "Inhaled fluticasone", "D": "Inhaled cromolyn", "E": "Oral montelukast"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Six days after being admitted to the hospital for a cholecystectomy, a 56-year-old woman has high-grade fevers, chills, malaise, and generalized weakness. She has been hospitalized twice in the last year for acute cholecystitis. She had a molar extraction around 2 weeks ago. Her last colonoscopy was 8 months ago and showed a benign polyp that was removed. She has mitral valve prolapse, hypertension, rheumatoid arthritis, and hypothyroidism. Current medications include metformin, rituximab, levothyroxine, and enalapril. Her temperature is 38.3°C (101°F), pulse is 112/min, and blood pressure is 138/90 mm Hg. Examination shows painless macules over her palms and soles and linear hemorrhages under her nail beds. The lungs are clear to auscultation. There is a grade 3/6 systolic murmur heard best at the apex. Blood is drawn and she is started on intravenous antibiotic therapy. Two sets of blood cultures grow coagulase-negative staphylococci. An echocardiography shows a large oscillating vegetation on the mitral valve and moderate mitral regurgitation. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Infected peripheral venous catheter", "options": {"A": "Predamaged heart valve", "B": "Colonic polyp", "C": "Recent dental procedure", "D": "Immunosuppression", "E": "Infected peripheral venous catheter"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-year-old right-handed boy is brought to the emergency department because of difficulty speaking and inability to raise his right arm. The patient’s mother says his symptoms started suddenly 1 hour ago and have not improved. She says he has never had these symptoms before. No other significant past medical history. The patient was born full-term via spontaneous transvaginal delivery and has met all developmental goals. The family immigrated from Nigeria 3 months ago, and the patient is currently following a vaccination catch-up schedule. His vital signs include: temperature 36.8°C (98.2°F), blood pressure 111/65 mm Hg, pulse 105/min. Height is at the 30th percentile and weight is at the 25th percentile for age and sex. Physical examination is remarkable for generalized pallor, pale conjunctiva, jaundice, and complete loss of strength in the right arm (0/5). His peripheral blood smear is shown in the picture. Which of the following is the most effective preventive measure for this patient’s condition?", "answer": "Regular blood transfusion", "options": {"A": "Warfarin", "B": "Aspirin", "C": "Carotid endarterectomy", "D": "Regular blood transfusion", "E": "Oral penicillin VK"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old woman comes to the physician because of progressive headache and fatigue for the past 2 months. One year ago, she was diagnosed with Cushing disease, which was ultimately treated with bilateral adrenalectomy. Current medications are hydrocortisone and fludrocortisone. Examination shows generalized hyperpigmentation of the skin and bitemporal visual field defects. Serum studies show an ACTH concentration of 1250 pg/mL (N = 20–100). Which of the following is the most appropriate next step in management?", "answer": "Perform radiotherapy of the pituitary", "options": {"A": "Administer bromocriptine", "B": "Administer metyrapone", "C": "Perform radiotherapy of the pituitary", "D": "Reduce dosage of glucocorticoids", "E": "Resect small cell lung carcinoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old woman presents to her family doctor worried that she might have a heart condition. For the past 7 months, she has been having short panic attacks where she feels short of breath, sweaty, and feels like her heart wants to jump out her chest. During these attacks, she feels like she ‘is going crazy’. She has now mapped out all of the places she has had an attack such as the subway, the crowded pharmacy near her house, and an elevator at her work that is especially slow and poorly lit. She actively avoids these areas to prevent an additional episode. She is afraid that during these attacks she may not be able to get the help she needs or escape if needed. No significant past medical history. The patient takes no current medications. Her grandfather died of a heart attack at the age of 70 and she is worried that it might run in the family. The patient is afebrile and vital signs are within normal limits. Laboratory results are unremarkable. Which of the following is the most likely diagnosis for this patient’s condition?", "answer": "Panic disorder and agoraphobia", "options": {"A": "Panic disorder and agoraphobia", "B": "Panic disorder", "C": "Social anxiety disorder", "D": "Agoraphobia", "E": "Generalized anxiety disorder"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old woman comes to the emergency department because of a mild headache, dizziness, fatigue, and nausea over the past several hours. She has no history of serious illness and takes no medications. She lives in a basement apartment and uses a wood stove for heating. Her temperature is 36°C (96.8°F) and pulse is 120/min. Arterial blood gas analysis shows a carboxyhemoglobin level of 11% (N = < 1.5). Which of the following mechanisms is the underlying cause of this patient's symptoms?", "answer": "Inhibition of mitochondrial cytochrome c oxidase", "options": {"A": "Inhibition of mitochondrial succinate dehydrogenase", "B": "Inhibition of mitochondrial ATP synthase", "C": "Increased oxygen binding capacity", "D": "Inhibition of mitochondrial cytochrome c oxidase", "E": "Increased mitochondrial membrane permeability"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old woman with a history of anorexia nervosa diagnosed 2 years ago presents for follow up. She says that, although she feels some improvement with cognitive-behavioral therapy (CBT), she is still struggling with her body image and fears gaining weight. She says that for the past 3 weeks she has noticed her ankles are uncomfortably swollen in the mornings. She also mentions that she still is having intermittent menstruation; her last menstrual cycle was 4 months ago. The patient denies any suicidal ideations. She has no other significant past medical history. She denies any history of smoking, alcohol consumption, or recreational drug use. The patient’s vital signs include: temperature 37.0°C (98.6°F), pulse 55/min, blood pressure 100/69 mm Hg, and respiratory rate 18/min. Her body mass index (BMI) is 17.1 kg/m2, improved from 16.9 kg/m2, 6 months ago. Her physical examination is significant for an irregular heart rhythm on cardiopulmonary auscultation. There is also significant 3+ pitting edema in the lower extremities bilaterally. An ECG reveals multiple isolated premature ventricular contractions (PVCs) with 1 10-sec episode of bigeminy. Which of the following aspects of this patient’s history and physical examination would be the strongest indication for inpatient hospitalization?", "answer": "Lower extremity edema", "options": {"A": "BMI of 17.1 kg/m2", "B": "Amenorrhea", "C": "Bigeminy", "D": "Pulse 55/min", "E": "Lower extremity edema"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 54-year-old man with a long-standing history of chronic obstructive pulmonary disease (COPD) presents to the clinic for progressive shortness of breath. The patient reports generalized fatigue, distress, and difficulty breathing that is exacerbated with exertion. Physical examination demonstrates clubbing of the fingers, and an echocardiogram shows right ventricular hypertrophy. The patient is placed on a medication for symptom control. One month later, the patient returns for follow up with some improvement in symptoms. Laboratory tests are drawn and shown below:\n\nSerum:\nNa+: 137 mEq/L\nCl-: 101 mEq/L\nK+: 4.8 mEq/L\nHCO3-: 25 mEq/L\nBUN: 8.5 mg/dL\nGlucose: 117 mg/dL\nCreatinine: 1.4 mg/dL\nThyroid-stimulating hormone: 1.8 µU/mL\nCa2+: 9.6 mg/dL\nAST: 159 U/L\nALT: 201 U/L\n\nWhat is the mechanism of action of the likely medication given?", "answer": "Competitive inhibition of endothelin-1 receptors", "options": {"A": "Beta-2 agonist", "B": "Competitive inhibition of endothelin-1 receptors", "C": "Competitive inhibition of muscarinic receptors", "D": "Inhibition of phosphodiesterase-5", "E": "Prostacylin with direct vasodilatory effects"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old woman, gravida 4, para 0, at 8 weeks' gestation comes to the physician for a prenatal visit. The previous pregnancies ended in spontaneous abortion between the 8th and 10th week of gestation. She feels well but is worried about having another miscarriage. She has no history of serious illness. Previous gynecologic evaluations showed no abnormalities. The patient takes a daily prenatal multivitamin. Her temperature is 36.5°C (97.7°F), pulse is 85/min, and blood pressure is 125/85 mm Hg. Examination shows a violaceous, reticular rash on the lower extremities.\nHemoglobin 10.5 g/dL\nLeukocyte count 5,200/mm3\nPlatelet count 120,000/mm3\nProthrombin time 13 seconds\nPartial thromboplastin time 49 seconds\nSerum\nNa+ 140 mEq/L\nK+ 4.4 mEq/L\nCl- 101 mEq/L\nUrea nitrogen 12 mg/dL\nCreatinine 1.1 mg/dL\nAST 20 U/L\nALT 15 U/L\nAnti-beta 2 glycoprotein-1 antibody positive\nWhich of the following is the most appropriate next step in management?\"", "answer": "Aspirin and enoxaparin", "options": {"A": "Heparin bridged to warfarin", "B": "Glucocorticoids and plasmapharesis", "C": "Aspirin and enoxaparin", "D": "Enoxaparin", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old Caucasian woman presents to her primary care physician’s office with a chief complaint of excessive facial and arm hair. On further questioning, she reveals that in the past year, she has often gone more than 3 months without menstruating. On exam she is well-appearing; her temperature is 98.6°F (37°C), blood pressure is 120/80 mmHg, pulse is 60/min, and BMI is 30 kg/m^2. Labwork confirms the suspected diagnosis. What is the best initial treatment (Rx) for this disease AND what other comorbid conditions (CC) should be tested for at this time?", "answer": "Rx: Weight loss, CC: Insulin resistance and lipid dysfunction", "options": {"A": "Rx: Combined oral contraceptives, CC: Infertility and insulin resistance", "B": "Rx: Weight loss, CC: Infertility and insulin resistance", "C": "Rx: Weight loss, CC: Infertility and lipid dysfunction", "D": "Rx: Combined oral contraceptives, CC: Insulin resistance and lipid dysfunction", "E": "Rx: Weight loss, CC: Insulin resistance and lipid dysfunction"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old man is brought to the emergency department 20 minutes after sustaining a gunshot wound to the abdomen. On arrival, he is awake and oriented to person, place, and time. He appears agitated. His pulse is 102/min, respirations are 20/min, and blood pressure is 115/70 mm Hg. The pupils are equal and reactive to light. Abdominal examination shows an entrance wound in the right upper quadrant above the umbilicus. There is an exit wound on the right lower back next to the lumbar spine. Breath sounds are normal bilaterally. There is diffuse mild tenderness to palpation with no guarding or rebound. Cardiac examination shows no abnormalities. Intravenous fluid therapy is begun. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the abdomen", "options": {"A": "CT scan of the abdomen", "B": "Close observation", "C": "Diagnostic laparoscopy", "D": "Immediate laparotomy", "E": "Diagnostic peritoneal lavage"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 42-year-old woman presents with fatigue. She says that her symptoms have gradually onset after she recently had a total thyroidectomy due to Graves’ disease. Past medical history is otherwise unremarkable. The patient is afebrile, and her vital signs are within normal limits. Physical examination is unremarkable. Laboratory findings are significant for the following:\n  Potassium 4.2 mEq/L\n  Calcium 7.8 mg/dL\n  Chloride 102 mEg/L\n  Vitamin D3 8 ng/mL (ref range: 25–80 ng/mL)\nA deficiency of which of the following is the most likely cause of this patient’s symptoms?", "answer": "Parathyroid hormone (PTH)", "options": {"A": "1-alpha-hydroxylase", "B": "Thyroid-stimulating hormone (TSH)", "C": "25-hydroxycholecalciferol", "D": "Calcitonin", "E": "Parathyroid hormone (PTH)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old female presents to her gynecologist for a check-up. She has had normal Pap smears as recommended every 3 years since she turned 30 years old. The physician conducts a pelvic examination that is without abnormality and obtains a cervical Pap smear. The results of the patient's Pap smear from the visit return as high grade squamous intraepithelial lesion (HGSIL). Which of the following is the best next step in the management of this patient?", "answer": "Perform colposcopy", "options": {"A": "Repeat Pap smear in 12 months", "B": "Repeat Pap smear in 3 years", "C": "Obtain HPV DNA test", "D": "Perform colposcopy", "E": "Radical hysterectomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 88-year-old man is brought to his primary care physician by his son. The patient has been in excellent health his entire life, but in the last few years appears to have grown steadily confused. He frequently calls his son about things that they have already discussed, forgets where he has placed his keys, and recently the patient's son noticed several unpaid bills on the patient's desk at home. The patient is upset at being \"dragged\" into see the physician and claims that everything is fine--he is just \"getting older\". A complete neurologic exam is normal except for significant difficulty with recall tasks. In the course of the medical work-up, you obtain a CT scan and see the findings in figure A. What is the most likely cause of this patient's CT findings?", "answer": "Cortical atrophy", "options": {"A": "Blockage of the cerebral aqueduct", "B": "Cortical atrophy", "C": "Increased CSF production", "D": "Congenital malformation", "E": "Infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 39-year-old woman presents to the family medicine clinic to be evaluated by her physician for weight gain. She reports feeling fatigued most of the day despite eating a healthy diet and exercising regularly. The patient smokes a half-pack of cigarettes daily and has done so for the last 23 years. She is employed as a phlebotomist by the Red Cross. She has a history of hyperlipidemia for which she takes atorvastatin. She is unaware of her vaccination history, and there is no documented record of her receiving any vaccinations. Her heart rate is 76/min, respiratory rate is 14/min, temperature is 37.3°C (99.1°F), body mass index (BMI) is 33 kg/m2, and blood pressure is 128/78 mm Hg. The patient appears alert and oriented. Lung and heart auscultation are without audible abnormalities. The physician orders a thyroid panel to determine if that patient has hypothyroidism. Which of the following recommendations may be appropriate for the patient at this time?", "answer": "Hepatitis B vaccination", "options": {"A": "Hepatitis B vaccination", "B": "Low-dose chest CT", "C": "Hepatitis C vaccination", "D": "Mammogram", "E": "Shingles vaccination"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 75-year-old man comes to the physician because of a 4-month history of progressive shortness of breath and chest pressure with exertion. Cardiac examination shows a crescendo-decrescendo systolic murmur that is heard best in the second right intercostal space. Radial pulses are decreased and delayed bilaterally. Transesophageal echocardiography shows hypertrophy of the left ventricle and a thick, calcified aortic valve. The area of the left ventricular outflow tract is 30.6 mm2. Using continuous-wave Doppler measurements, the left ventricular outflow tract velocity is 1.0 m/s, and the peak aortic valve velocity is 3.0 m/s. Which of the following values most closely represents the area of the stenotic aortic valve?", "answer": "10.2 mm2", "options": {"A": "16.0 mm2", "B": "10.2 mm2", "C": "23 mm2", "D": "6.2 mm2", "E": "2.0 mm2"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A newborn male born prematurely at 33 weeks is noted to have mild dyspnea and difficulty with feeding. Examination reveals bounding peripheral radial pulses and a continuous 'machine-like' murmur. The patient is subsequently started on indomethacin. Which of the following is the embryologic origin of the structure most likely responsible for this patient's presentation?", "answer": "6th aortic arch", "options": {"A": "1st branchial cleft", "B": "4th branchial arch", "C": "4th branchial pouch", "D": "6th aortic arch", "E": "6th branchial pouch"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-year-old female visits your obstetrics clinic for her first prenatal check up. It's her first month of pregnancy and other than morning sickness, she is feeling well. Upon inquiring about her past medical history, the patient admits that she used to be very fearful of weight gain and often used laxatives to lose weight. After getting therapy for this condition, she regained her normal body weight but continues to struggle with the disease occasionally. Given this history, how could her past condition affect the pregnancy?", "answer": "Postpartum depression for mother", "options": {"A": "Down syndrome in newborn", "B": "Postpartum depression for mother", "C": "Bradycardia in newborn", "D": "Anemia in newborn", "E": "Seizure for mother"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old boy presents to the pediatrician's office for a well child checkup. He does not speak during the visit and will not make eye contact. The father explains that the child has always been shy with strangers. However, the child speaks a lot at home and with friends. He can speak in 4 word sentences, tells stories, and parents understand 100% of what he says. He names colors and is starting to recognize letters. However, his pre-kindergarten teachers are concerned that even after 5 months in their class, he does not speak during school at all. The father notes that he is equally as shy in church, which he has been going to his entire life. Which of the following is most likely?", "answer": "Selective mutism", "options": {"A": "Autism spectrum disorder", "B": "Child abuse at school", "C": "Expressive speech delay", "D": "Normal development", "E": "Selective mutism"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old man with Alzheimer disease is brought to the emergency department 20 minutes after ingesting an unknown amount of his medications in a suicide attempt. He reports abdominal cramps, diarrhea, diaphoresis, and muscular weakness and spasms in his extremities. His temperature is 38.4°C (101.1°F), pulse is 51/min, respirations are 12/min and labored, and blood pressure is 88/56 mm Hg. Physical examination shows excessive salivation and tearing, and small pupils bilaterally. Treatment with atropine is initiated. Shortly after, most of his symptoms have resolved, but he continues to have muscular spasms. Administration of which of the following is the most appropriate next step in management of this patient?", "answer": "Pralidoxime", "options": {"A": "Carbachol", "B": "Physostigmine", "C": "Pancuronium", "D": "Benztropine", "E": "Pralidoxime"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 46-year-old woman comes to the physician because of a 3-day history of diarrhea and abdominal pain. She returned from a trip to Egypt 4 weeks ago. Her vital signs are within normal limits. There is mild tenderness in the right lower quadrant. Stool studies show occult blood and unicellular organisms with engulfed erythrocytes. Which of the following is the most appropriate initial pharmacotherapy for this patient?", "answer": "Metronidazole", "options": {"A": "Doxycycline", "B": "Metronidazole", "C": "Albendazole", "D": "Paromomycin", "E": "Ciprofloxacin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old woman is brought to the emergency department after being involved in a motor vehicle collision. She is alert, awake, and oriented. There is no family history of serious illness and her only medication is an oral contraceptive. Her temperature is 37.3°C (99°F), pulse is 100/min, respirations are 20/min, and blood pressure is 102/80 mm Hg. Physical examination shows ecchymoses over the trunk and abdomen. A FAST scan of the abdomen is negative. An x-ray of the chest shows no fractures. A contrast-enhanced CT scan of the chest and abdomen is performed that shows a 4-cm sharply defined liver mass with a hypoattenuated central scar. Which of the following is the most appropriate next step in management?", "answer": "Reassurance and observation", "options": {"A": "Reassurance and observation", "B": "Biopsy of the mass", "C": "Discontinue the oral contraceptive", "D": "Percutaneous aspiration of the mass", "E": "Surgical resection of the mass"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Two hours after a 2280-g male newborn is born at 38 weeks' gestation to a 22-year-old primigravid woman, he has 2 episodes of vomiting and jitteriness. The mother has noticed that the baby is not feeding adequately. She received adequate prenatal care and admits to smoking one pack of cigarettes daily while pregnant. His temperature is 36.3°C (97.3°F), pulse is 171/min and respirations are 60/min. Pulse oximetry on room air shows an oxygen saturation of 92%. Examination shows pale extremities. There is facial plethora. Capillary refill time is 3 seconds. Laboratory studies show:\nHematocrit 70%\nLeukocyte count 7800/mm3\nPlatelet count 220,000/mm3\nSerum\nGlucose 38 mg/dL\nCalcium 8.3 mg/dL\nWhich of the following is the most likely cause of these findings?\"", "answer": "Intrauterine hypoxia\n\"", "options": {"A": "Transient tachypnea of the newborn", "B": "Intraventricular hemorrhage", "C": "Hyperinsulinism", "D": "Congenital heart disease", "E": "Intrauterine hypoxia\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 20-year-old man comes to the physician because of dark urine and decreased urine output for 2 days. He had a skin infection that required antibiotic treatment 3 weeks ago but stopped the antibiotics early because the infection had resolved. His blood pressure is 140/90 mm Hg. Physical examination shows periorbital edema bilaterally. A photomicrograph of a renal biopsy specimen is shown. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Elevated Anti-DNase B titer", "options": {"A": "Mutation in type IV collagen", "B": "Impaired glutathione regeneration", "C": "Mesangial IgA deposition", "D": "Decreased platelet count", "E": "Elevated Anti-DNase B titer"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 7-year-old boy with a history of fetal alcohol syndrome is brought by his mother to the emergency room for malaise and lethargy. His mother reports that the family was on vacation in a cabin in the mountains for the past 10 days. Five days ago, the child developed a fever with a max temperature of 102.6°F (39.2°F). She also reports that he was given multiple medications to try to bring down his fever. Although his fever resolved two days ago, the child has become increasingly lethargic. He started having non-bilious, non-bloody emesis one day prior to presentation. His current temperature is 100°F (37.8°C), blood pressure is 95/55 mmHg, pulse is 110/min, and respirations are 22/min. On exam, the child is lethargic and minimally reactive. Mild hepatomegaly is noted. A biopsy of this patient’s liver would likely reveal which of the following?", "answer": "Microvesicular steatosis", "options": {"A": "Microvesicular steatosis", "B": "Macrovesicular steatosis", "C": "Hepatocyte necrosis with ballooning degeneration", "D": "Macronodular cirrhosis", "E": "Micronodular cirrhosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old woman presents to the ED with a diffuse, erythematous rash in the setting of nausea, vomiting, and fever for 2 days. Physical exam reveals a soaked tampon in her vagina. Blood cultures are negative. The likely cause of this patient's disease binds to which molecule on T cells?", "answer": "Variable beta portion of the T-cell receptor", "options": {"A": "CD3", "B": "Gamma chain of the IL-2 receptor", "C": "CD40 ligand", "D": "Variable beta portion of the T-cell receptor", "E": "Fas ligand"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old woman comes to the physician because of pain and swelling of her left foot. Three days ago, she cut her foot on an exposed rock at the beach. Her temperature is 37.7°C (100°F). Examination of the left foot shows edema around a fluctuant erythematous lesion on the lateral foot. Which of the following is most likely the primary mechanism for the development of edema in this patient?", "answer": "Separation of endothelial junctions", "options": {"A": "Fluid production by bacteria", "B": "Increased capillary hydrostatic pressure", "C": "Decreased plasma oncotic pressure", "D": "Systemic cytokine release", "E": "Separation of endothelial junctions"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old woman with a history of atrial arrhythmia arrives in the emergency department with complaints of tinnitus, headache, visual disturbances, and severe diarrhea. The patient is given oxygen by nasal cannula. ECG leads, pulse oximeter and an automated blood pressure cuff are applied. The patient suddenly faints. Her ECG indicates the presence of a multifocal ventricular tachycardia with continuous change in the QRS electrical axis. Which of the following drugs is most likely responsible for this patient's symptoms?", "answer": "Quinidine", "options": {"A": "Digoxin", "B": "Quinidine", "C": "Lidocaine", "D": "Amiodarone", "E": "Verapamil"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old soldier is rescued from a helicopter crash in the Arctic Circle and brought back to a treatment facility at a nearby military base. On arrival, the patient's wet clothes are removed. He appears pale and is not shivering. He is unresponsive to verbal and painful stimuli. His temperature is 27.4°C (81.3°F), pulse is 30/min and irregular, respirations are 7/min, and blood pressure is 83/52 mm Hg. Examination shows fixed, dilated pupils and diffuse rigidity. The fingers and toes are white in color and hard to the touch. An ECG shows atrial fibrillation. In addition to emergent intubation, which of the following is the most appropriate next step in management?", "answer": "Intravenous administration of warmed normal saline", "options": {"A": "Intravenous administration of tissue plasminogen activator", "B": "Intravenous administration of diltiazem", "C": "Application of heating pads to the extremities", "D": "Intravenous administration of warmed normal saline", "E": "Emergent electrical cardioversion"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 44-year-old woman comes to the physician for the evaluation of right knee pain for 1 week. The pain began after the patient twisted her knee during basketball practice. At the time of the injury, she felt a popping sensation and her knee became swollen over the next few hours. The pain is exacerbated by walking up or down stairs and worsens throughout the day. She also reports occasional locking of the knee. She has been taking acetaminophen during the past week, but the pain is worse today. Her mother has rheumatoid arthritis. The patient is 155 cm (4 ft 11 in) tall and weighs 75 kg (165 lb); BMI is 33 kg/m2. Vital signs are within normal limits. Examination shows effusion of the right knee; range of motion is limited by pain. There is medial joint line tenderness. Knee extension with rotation results in an audible snap. Further evaluation is most likely to show which of the following?", "answer": "Hyperintense line in the meniscus on MRI", "options": {"A": "Hyperintense line in the meniscus on MRI", "B": "Anterior tibial translation on examination", "C": "Trabecular loss in the proximal femur on x-ray", "D": "Erosions and synovial hyperplasia on MRI", "E": "Posterior tibial translation on examination"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 31-year-old man living in a remote tropical village presents with a swollen left leg and scrotum (see image). He says that his symptoms started more than 2 years ago with several small swollen areas near his groin and have gradually and progressively worsened. He has also noticed that over time, there has been a progressive coarsening and fissuring of the skin overlying the swollen areas. Blood samples drawn at night show worm-like organisms under microscopy. Which of the following arthropods is the vector for the organism most likely responsible for this patient’s condition?", "answer": "Mosquito", "options": {"A": "Mosquito", "B": "Tick", "C": "Tsetse fly", "D": "Sandfly", "E": "Human louse"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old female is found to have an inherited deficiency of alpha-galactosidase A. Skin biopsy shows accumulation of ceramide trihexose in the tissue. Which of the following abnormalities would be expected in this patient?", "answer": "Angiokeratomas", "options": {"A": "Cherry red spots on macula", "B": "Histiocytes with a wrinkled tissue paper appearance", "C": "Gargoyle-like facies", "D": "Corneal clouding", "E": "Angiokeratomas"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 39-year-old woman presents to your office with 4 days of fever, sore throat, generalized aching, arthralgias, and tender nodules on both of her shins that arose in the last 48 hours. Her medical history is negative for disease and she does not take oral contraceptives or any other medication regularly. The physical examination reveals the vital signs that include body temperature 38.5°C (101.3°F), heart rate 85/min, blood pressure 120/65 mm Hg, tender and enlarged submandibular lymph nodes, and an erythematous, edematous, and swollen pharynx with enlarged tonsils and a patchy white exudate on the surface. She is not pregnant. Examination of the lower limbs reveals erythematous, tender, immobile nodules on both shins. You do not identify ulcers or similar lesions on other areas of her body. What is the most likely diagnosis in this patient?", "answer": "Erythema nodosum", "options": {"A": "Alpha-1 antitrypsin deficiency", "B": "Erythema induratum", "C": "Cutaneous polyarteritis nodosa", "D": "Henoch-Schönlein purpura", "E": "Erythema nodosum"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 66-year-old man is brought to the emergency department because of weakness of his left leg for the past 30 minutes. His pants are soaked with urine. He has hypertension and atrial fibrillation. His temperature is 37°C (98.6°F), pulse is 98/min, and blood pressure is 160/90 mm Hg. Examination shows equal pupils that are reactive to light. Muscle strength is 2/5 in the left lower extremity. Plantar reflex shows an extensor response on the left. Within one minute of the onset of this patient's symptoms, the cells in his right anteromedial cortical surface enlarge significantly. Which of the following is the most likely explanation of the described cellular change?", "answer": "Intracellular depletion of ATP", "options": {"A": "Rupture of lysosomes", "B": "Influx of extracellular calcium", "C": "Intracellular depletion of ATP", "D": "Release of pro-apoptotic proteins", "E": "Breakdown of the cell membrane"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old male presents to his primary care physician after an injury during a rugby game. The patient states that he was tackled and ever since then has had pain in his knee. The patient has tried NSAIDs and ice to no avail. The patient has no past medical history and is currently taking a multivitamin, fish oil, and a whey protein supplement. On physical exam you note a knee that is heavily bruised. It is painful for the patient to bear weight on the knee, and passive motion of the knee elicits some pain. There is laxity at the knee to varus stress. The patient is wondering when he can return to athletics. Which of the following is the most likely diagnosis?", "answer": "Lateral collateral ligament tear", "options": {"A": "Medial collateral ligament tear", "B": "Lateral collateral ligament tear", "C": "Anterior cruciate ligament tear", "D": "Posterior cruciate ligament tear", "E": "Meniscal tear"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 80-year-old woman is brought to the emergency department due to the gradual worsening of confusion and lethargy for the past 5 days. Her son reports that she had recovered from a severe stomach bug with vomiting and diarrhea 3 days ago without seeing a physician or going to the hospital. The patient’s past medical history is notable for type 2 diabetes mellitus and hypertension. She takes hydrochlorothiazide, metformin, a children’s aspirin, and a multivitamin. The patient is not compliant with her medication regimen. Physical examination reveals dry oral mucous membranes and the patient appears extremely lethargic but arousable. She refuses to answer questions and has extreme difficulty following the conversation. Laboratory results are as follows:\nSodium 126 mEq/L\nPotassium 3.9 mEq/L\nChloride 94 mEq/L\nBicarbonate 25 mEq/L\nCalcium 8.1 mg/dL\nGlucose 910 mg/dL\nUrine ketones Trace\nWhich of the following may also be found in this patient?", "answer": "Increased BUN/creatinine ratio", "options": {"A": "Characteristic breath odor", "B": "Flapping hand tremor", "C": "Increased BUN/creatinine ratio", "D": "Diffuse abdominal pain", "E": "Rapid and deep respiration"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 73-year-old man presents to the emergency department complaining of abdominal pain with nausea and vomiting, stating that he “can’t keep anything down”. He states that the pain has been gradually getting worse over the past 2 months, saying that, at first, it was present only an hour after he ate but now is constant. He also says that he has been constipated for the last 2 weeks, which has also been getting progressively worse. His last bowel movement was 4 days ago which was normal. He states that he cannot pass flatus. The patient’s past medical history is significant for hypertension and an episode of pneumonia last year. The patient is afebrile and his pulse is 105/min. On physical examination, the patient is uncomfortable. His lungs are clear to auscultation bilaterally. His abdomen is visibly distended and diffusely tender with tympany on percussion. A contrast CT scan of the abdomen shows dilated loops of small bowel with collapsed large bowel. Which of the following is the most likely cause of this patient’s condition?", "answer": "Mass effect from a tumor", "options": {"A": "Incarcerated hernia", "B": "Mass effect from a tumor", "C": "Crohn's disease", "D": "Adhesions", "E": "Diverticulitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 20-year-old college student has elevated stress levels due to her rigorous academic schedule, social commitments, and family pressures. She complains of never having enough time for all her responsibilities. Which of the following hormones acts by intracellular receptors to exert the physiologic effects of her stress?", "answer": "Cortisol", "options": {"A": "Cortisol", "B": "Glucagon", "C": "Growth hormone", "D": "Norepinephrine", "E": "Prolactin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 61-year-old female is referred to an oncologist for evaluation of a breast lump that she noticed two weeks ago while doing a breast self-examination. Her past medical history is notable for essential hypertension and major depressive disorder for which she takes lisinopril and escitalopram, respectively. Her temperature is 98.6°F (37°C), blood pressure is 120/65 mmHg, pulse is 82/min, and respirations are 18/min. Biopsy of the lesion confirms a diagnosis of invasive ductal carcinoma with metastatic disease in the ipsilateral axillary lymph nodes. The physician starts the patient on a multi-drug chemotherapeutic regimen. The patient successfully undergoes mastectomy and axillary dissection and completes the chemotherapeutic regimen. However, several months after completion of the regimen, the patient presents to the emergency department with dyspnea, chest pain, and palpitations. A chest radiograph demonstrates an enlarged cardiac silhouette. This patient’s current symptoms could have been prevented by administration of which of the following medications?", "answer": "Dexrazoxane", "options": {"A": "Vincristine", "B": "Dexrazoxane", "C": "Aspirin", "D": "Rosuvastatin", "E": "Cyclophosphamide"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old woman presents with frequent headaches for the past few months. She says the pain starts randomly and is unrelated to any stimulus. She also says that has difficulty falling asleep and has had problems concentrating at work for several months. While she occasionally thinks about committing suicide, she denies any suicidal plans. Her appetite is diminished. No significant past medical history. No current medications. There is no family history of depression or psychiatric illness. The physical exam is unremarkable. The thyroid-stimulating hormone (TSH) level is 3.5 uU/mL. The patient is started on amitriptyline and asked to follow-up in 2 weeks. At her follow-up visit, the patient reports slight improvement in her mood and has no more headaches, but she complains of lightheadedness when she rises out of bed in the morning or stands up from her desk at work. Which of the following pharmacological effects of amitriptyline is most likely responsible for her lightheadedness?", "answer": "Blockage of α1 adrenergic receptors", "options": {"A": "Blockage of muscarinic receptors", "B": "Decreased reuptake of norepinephrine", "C": "Blockage of α1 adrenergic receptors", "D": "Decreased reuptake of serotonin", "E": "Blockage of H1 histamine receptors"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A new real time-PCR test for the hepatitis C virus is approved for medical use. The manufacturer sets the threshold number of DNA copies required to achieve a positive result such that the sensitivity is 98% and the specificity is 80%. The tested population has a hepatitis C prevalence of 0.7%. Which of the following changes in the prevalence, incidence, or threshold concentration will increase the positive predictive value of the test, if the other two values are held constant?", "answer": "An increase in prevalence", "options": {"A": "An increase in incidence", "B": "An increase in prevalence", "C": "A decrease in incidence", "D": "A decrease in prevalence", "E": "Lowering the threshold concentration required for a positive test."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4080-g (9-lb) male newborn is delivered at term to a 32-year-old woman, gravida 2, para 1. Apgar scores are 8 and 9 at 1- and 5-minutes, respectively. Examination in the delivery room shows both feet pointing downwards and inwards. Both the forefeet are twisted medially in adduction, with the hindfeet elevated and the midfeet appearing concave. Both Achilles tendons are taut on palpation. There are skin creases on the medial side of both feet. The deformity persists despite attempts to passively straighten the foot. X-rays of both feet confirm the suspected diagnosis. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Repositioning and serial casting", "options": {"A": "Foot abduction brace", "B": "Surgery", "C": "Reassurance", "D": "Repositioning and serial casting", "E": "Physiotherapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4390-g (9-lb 11-oz) male newborn is delivered at term to a 28-year-old primigravid woman. Pregnancy was complicated by gestational diabetes mellitus. Labor was prolonged by the impaction of the fetal shoulder and required hyperabduction of the left upper extremity. Apgar scores were 7 and 8 at 1 and 5 minutes, respectively. Vital signs are within normal limits. Examination in the delivery room shows a constricted left pupil. There is drooping of the left eyelid. Active movement of the left upper extremity is reduced. Further evaluation of this newborn is most likely to show which of the following?", "answer": "Absent unilateral grasp reflex", "options": {"A": "Generalized hypotonia", "B": "Absent nasolabial fold", "C": "Absent unilateral grasp reflex", "D": "Lower back mass", "E": "Decreased movement of unilateral rib cage\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old girl presents to the emergency department after persistent vomiting and complaints that her abdomen hurts. Her parents came home to their daughter like this while she was at home being watched by the babysitter. The child is otherwise healthy. Family history is notable for depression, suicide, neuropathic pain, diabetes, hypertension, cancer, and angina. The child is now minimally responsive and confused. Her temperature is 100°F (37.8°C), blood pressure is 100/60 mmHg, pulse is 140/min, respirations are 22/min, and oxygen saturation is 100% on room air. Physical exam is notable for a confused girl who is vomiting bloody emesis into a basin. Laboratory studies are ordered as seen below.\n\nSerum:\nNa+: 140 mEq/L\nCl-: 101 mEq/L\nK+: 3.9 mEq/L\nHCO3-: 11 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.0 mg/dL\n\nRadiography is notable for a few radiopaque objects in the stomach. Urine and serum toxicology are pending. Which of the following is the most likely intoxication?", "answer": "Iron", "options": {"A": "Acetaminophen", "B": "Aspirin", "C": "Iron", "D": "Lead", "E": "Nortriptyline"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70-year-old woman comes to the physician because of a 4-month history of fatigue, worsening swelling of her ankles, and a 5-kg (11-lb) weight gain. Neurologic examination shows diminished two-point discrimination in her fingers. Laboratory studies show a hemoglobin A1c concentration of 9.2% and a creatinine concentration of 1.3 mg/dL. Urine dipstick shows heavy proteinuria. A biopsy specimen of this patient's kidney is most likely to show which of the following?", "answer": "Nodular glomerulosclerosis", "options": {"A": "Split glomerular basement membrane", "B": "Immune complex deposition", "C": "Interstitial inflammation", "D": "Wire looping of capillaries", "E": "Nodular glomerulosclerosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 11-year-old male with light purple eyes presents with gradual loss of bilateral visual acuity. Over the past several years, vision has worsened from 20/20 to 20/100 in both eyes. He also has mild nystagmus when focusing on objects such as when he is trying to do his homework. He is diagnosed with a disease affecting melanin production in the iris. If both of his parents are unaffected, which of the following represents the most likely probabilities that another male or female child from this family would be affected by this disorder?", "answer": "Male: 50% Female: 0%", "options": {"A": "Same as general population", "B": "Male: 25% Female: 25%", "C": "Male: 50% Female: 50%", "D": "Male: 50% Female: 0%", "E": "Male: 100% Female: 0%"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 75-year-old man comes to his primary care physician because he has been having diarrhea and difficulty breathing. The diarrhea has been intermittent with frequent watery stools that occur along with abdominal cramps. Furthermore, the skin on his face and upper chest feels hot and changes color in episodes lasting from a few minutes to hours. Finally, the patient complains of loss of appetite and says that he has unexpectedly lost 20 pounds over the last two months. Based on clinical suspicion, magnetic resonance imaging is obtained showing a small mass in this patient's lungs. Which of the following is associated with the most likely cause of this patient's symptoms?", "answer": "It also arises in the GI tract", "options": {"A": "Contains psammoma bodies", "B": "It also arises in the GI tract", "C": "Has keratin pearls and intercellular bridges", "D": "Most common lung cancer in non-smokers and females", "E": "Stains positive for vimentin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 8-year-old boy is brought to the physician by his foster mother because of complaints from his teachers regarding poor performance at school for the past 8 months. He does not listen to their instructions, often talks during class, and rarely completes his school assignments. He does not sit in his seat in the classroom and often cuts in line at the cafeteria. His foster mother reports that he runs around a lot inside the house and refuses to help his sister with chores and errands. He frequently interrupts his foster mother's conversations with others and talks excessively. She has found him trying to climb on the roof on multiple occasions. He was placed in foster care because of neglect by his biological parents 3 years ago. Physical examination shows no abnormalities. Neurologic examination shows no focal findings. Mental status examination shows a neutral affect. Which of the following is the most likely diagnosis?", "answer": "Attention-deficit/hyperactivity disorder", "options": {"A": "Age-appropriate behavior", "B": "Conduct disorder", "C": "Oppositional defiant disorder", "D": "Attention-deficit/hyperactivity disorder", "E": "Hearing impairment"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old Caucasian male is brought to the emergency room for recurrent diarrhea. He has had multiple upper respiratory infections since birth and does not take any medications at home. It is determined that Giardia lamblia is responsible for the recurrent diarrhea. The physician performs a serum analysis and finds normal levels of mature B lymphocytes. What other finding on serum analysis predisposes the patient to recurrent diarrheal infections?", "answer": "Deficiency in IgA", "options": {"A": "Deficiency in CD8+ T cells", "B": "Deficiency in neutrophils", "C": "Deficiency in IgA", "D": "Deficiency in NK cells", "E": "Deficiency in IgG"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Paramedics are called to a 35-year-old man who had accidentally amputated his left index finger tip with a knife. He has no significant past medical history. His temperature is 37.2°C (99°F), pulse is 96/min, and blood pressure is 112/72 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 99%. His left index finger is amputated distal to the distal interphalangeal joint at the level of the nail bed, and exposed bone is visible. There is profuse bleeding from the wound site. His ability to flex, extend, abduct, and adduct the joints is preserved and sensation is intact. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step prior to transporting this patient to the emergency department?", "answer": "Wrap finger tip in gauze damp with saline in a sealed plastic bag placed on ice water", "options": {"A": "Wrap finger in gauze wet with iodine in a sealed plastic bag placed on ice", "B": "Preserve finger tip in cooled saline water", "C": "Preserve finger tip in warm saline water", "D": "Wrap finger tip in gauze damp with saline in a sealed plastic bag placed on ice water", "E": "Place finger tip on ice in a sealed plastic bag"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old medical student presents to a community health center due to an episode of loss of consciousness 3 days ago. She also has a history of multiple episodes of dizziness in the last year. These episodes almost always occur when she is observing surgery in the operating room. She describes her dizziness as a feeling of lightheadedness, warmth, excessive sweating, and palpitations. She feels that she will fall down if she stood longer and usually sits on the floor or leaves the room until the feeling subsides. Three days ago, she collapsed while observing an open cholecystectomy but regained consciousness after a few seconds. Once she regained consciousness, she was pale and sweating excessively. Her medical history is significant for migraines, but she is not on prophylactic therapy. Her younger brother has cerebral palsy, and her uncle had a sudden death at the age of 25. Her blood pressure is 120/80 mm Hg when lying down and 118/80 mm Hg when in a standing position. The rest of the physical examination is within normal limits. What is the next best step in the management of this patient?", "answer": "Electrocardiogram (ECG)", "options": {"A": "Echocardiogram", "B": "Electrocardiogram (ECG)", "C": "Electroencephalogram (EEG)", "D": "MRI of the brain", "E": "Psychiatric evaluation for anxiety"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 51-year-old Caucasian female presents to her primary care provider complaining of intermittent chest pain. She reports that over the past 6 months, she has developed burning chest pain that occurs whenever she exerts herself. The pain decreases when she rests. Her past medical history is notable for type II diabetes mellitus. Her family history is notable for multiple myocardial infarctions in her father and paternal grandmother. She currently takes aspirin and metformin. Her primary care provider starts her on a medication which is indicated given her medical history and current symptoms. However, 10 days later, she presents to the emergency room complaining of weakness and muscle pain. Her plasma creatine kinase level is 250,000 IU/L. This patient was most likely started on a medication that inhibits an enzyme that produces which of the following?", "answer": "Mevalonic acid", "options": {"A": "Farnesyl pyrophosphate", "B": "HMG-CoA", "C": "Lanosterol", "D": "Mevalonic acid", "E": "Squalene"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 26-year-old man presents to his primary care physician complaining of impotence. He reports that he has a healthy, long-term relationship with a woman whom he hopes to marry, but he is embarrassed that he is unable to have an erection. Which of the following is the next best step?", "answer": "Evaluate nocturnal tumescence", "options": {"A": "Obtain a sperm sample", "B": "Evaluate nocturnal tumescence", "C": "Duplex penile ultrasound", "D": "Prescribe sildenafil", "E": "Prescribe vardenafil"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A cohort study was done to assess the differential incidence of diabetes in patients consuming a typical western diet, versus those consuming a Mediterranean diet. A total of 600 subjects were included with 300 in each arm. Results are as follows:\n  Diabetes development No-diabetes development\nWestern diet 36 264\nMediterranean diet 9 291\nWhat is the odds ratio of developing diabetes for a given subject consuming the western diet as compared to a subject who consumes the Mediterranean diet?", "answer": "4.4", "options": {"A": "1.0", "B": "3.2", "C": "4.4", "D": "5.6", "E": "6.7"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Researchers are investigating the effects of an Amazonian plant extract as a novel therapy for certain types of tumors. When applied to tumor cells in culture, the extract causes widespread endoplasmic reticulum stress and subsequent cell death. Further experiments show that the extract acts on an important member of a protein complex that transduces proliferation signals. When this protein alone is exposed to the plant extract, its function is not recovered by the addition of chaperones. Which type of bond is the extract most likely targeting?", "answer": "Covalent bonds between carboxyl and amino groups", "options": {"A": "Hydrogen bonds", "B": "Ionic bonds", "C": "Hydrophobic interactions", "D": "Covalent bond between two sulfide groups", "E": "Covalent bonds between carboxyl and amino groups"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old woman accompanied by her husband presents to the emergency department after loss of consciousness 30 minutes ago. The husband reports that she was sitting in a chair at home and began having sustained rhythmic contractions of all 4 extremities for approximately 1 minute. During transport via ambulance she appeared confused but arousable. Her husband reports she has no medical conditions, but for the past 2 months she has occasionally complained of episodes of sweating, palpitations, and anxiety. Her brother has epilepsy and her mother has type 1 diabetes mellitus. Laboratory studies obtained in the emergency department demonstrate the following:\n\nSerum:\nNa+: 136 mEq/L\nK+: 3.8 mEq/L\nCl-: 100 mEq/L\nHCO3-: 19 mEq/L\nBUN: 16 mg/dL\nCreatinine: 0.9 mg/dL\nGlucose: 54 mg/dL\nC-peptide: Low\n\nWhich of the following is the most likely diagnosis?", "answer": "Surreptitious insulin use", "options": {"A": "Alpha cell tumor", "B": "Beta cell tumor", "C": "Diabetic ketoacidosis", "D": "Surreptitious insulin use", "E": "Surreptitious sulfonylurea use"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A healthy 36-year-old Caucasian man takes part in an experimental drug trial. The drug is designed to lower glomerular filtration rate (GFR) while simultaneously raising the filtration fraction. Which of the following effects on the glomerulus would you expect the drug to have?", "answer": "Afferent arteriole constriction and efferent arteriole constriction", "options": {"A": "Afferent arteriole constriction and efferent arteriole vasodilation", "B": "Afferent arteriole constriction and efferent arteriole constriction", "C": "Afferent arteriole dilation and efferent arteriole vasodilation", "D": "Afferent arteriole dilation and efferent arteriole constriction", "E": "Increased oncotic pressure in Bowman's space"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A pathologist is investigating the cytology of cells that have been infected with a particularly virulent strain of the influenza virus. The physician suspects that the virus results in cell death after viral replication in order to expedite the spread of the virus. She recalls that there are three known biochemical mechanisms of initiating programmed cellular death: 1) transmembrane receptor-mediated interaction, 2) stimuli producing intracellular signals leading to mitochondrial-initiated events, and 3) release of cytoplasmic granules into a cell via a perforin molecule. Which of the following biochemical components plays a common role in all of these 3 processes?", "answer": "Caspase-3", "options": {"A": "FAS ligand", "B": "Caspase-3", "C": "Bax", "D": "Bcl-2", "E": "CD-95 protein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old girl is hospitalized because of increased fatigue and weight loss over the past 2 months. The patient has no personal or family history of a serious illness. She takes no medications, currently. Her blood pressure is 175/74 mm Hg on the left arm and 90/45 on the right. The radial pulse is 84/min but weaker on the right side. The femoral blood pressure and pulses show no abnormalities. Temperature is 38.1℃ (100.6℉). The muscles over the right upper arm are slightly atrophic. The remainder of the examination reveals no abnormalities. Laboratory studies show the following results:\nHemoglobin 10.4 g/dL\nLeukocyte count 5,000/mm3\nErythrocyte sedimentation rate 58 mm/h\nMagnetic resonance arteriography reveals irregularity, stenosis, and poststenotic dilation involving the proximal right subclavian artery. Prednisone is initiated with improvement of her symptoms. Which of the following is the most appropriate next step in the patient management?", "answer": "Carvedilol + hydrochlorothiazide", "options": {"A": "Carvedilol + hydrochlorothiazide", "B": "Cyclophosphamide", "C": "Plasmapheresis", "D": "Rituximab", "E": "Surgery"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A neonate appears irritable and refuses to feed. The patient is febrile and physical examination reveals a bulge at the anterior fontanelle. A CSF culture yields Gram-negative bacilli that form a metallic green sheen on eosin methylene blue (EMB) agar. The virulence factor most important to the development of infection in this patient is:", "answer": "K capsule", "options": {"A": "Exotoxin A", "B": "LPS endotoxin", "C": "Fimbrial antigen", "D": "IgA protease", "E": "K capsule"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old female is brought to the primary care clinic by her mother. The mother is concerned about her daughter’s grades, which have been recently slipping. Per the mother, the patient usually earns a mix of As and Bs in her classes, but this past semester she has been getting Cs and a few Ds. Her mother is also frustrated because she feels like her daughter is acting out more and “hanging out with some no-good friends.” Upon questioning the patient with her mother in the room, the patient does not say much and makes no eye contact. The mother is asked to leave the room and the patient is questioned again about any stressors. After rapport is established, the patient breaks down and tearfully admits to trying various drugs in order to “fit in with her friends.” She says that she knows the drugs “are not good for me” but has been very stressed out about telling her friends she’s not interested. Detailed questioning reveals that the patient has been using alcohol, cocaine, and marijuana 2-3 times per week. The patient becomes agitated at the end of the interview and pleads for you to not tell her mother. She says that she knows they’re illegal but is very afraid of what her parents would say. What is the best action in response to the adolescent’s request?", "answer": "Reassure the patient that there is confidentiality in this situation but encourage her to tell her mother", "options": {"A": "Apologize and say that you must inform her mother because the use of these drugs is illegal", "B": "Apologize and say that you must inform legal authorities because the use of these drugs is illegal", "C": "Apologize and say that you must inform her mother because these drugs pose a danger to her health", "D": "Agree to the patient’s request and do not inform the patient’s mother", "E": "Reassure the patient that there is confidentiality in this situation but encourage her to tell her mother"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old woman comes to the physician because of a 2-week history of severe, retrosternal chest pain. She also has pain when swallowing solid food and medications. She has hypertension, type 2 diabetes mellitus, poorly-controlled asthma, and osteoporosis. She was recently admitted to the hospital for an acute asthma exacerbation that was treated with bronchodilators and a 7-day course of oral corticosteroids. Her current medications include aspirin, amlodipine, metformin, insulin, beclomethasone and albuterol inhalers, and alendronate. Vital signs are within normal limits. Examination of the oral pharynx appears normal. The lungs are clear to auscultation. An upper endoscopy shows a single punched-out ulcer with normal surrounding mucosa at the gastroesophageal junction. Biopsies of the ulcer are taken. Which of the following is the most appropriate next step in management?", "answer": "Discontinue alendronate", "options": {"A": "Start ganciclovir", "B": "Discontinue alendronate", "C": "Start pantoprazole", "D": "Discontinue amlodipine", "E": "Start fluconazole"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 36-year-old woman is admitted to the hospital because of irritability, nausea, and diarrhea. She has a history of recreational oxycodone use and last took a dose 48 hours ago. Physical examination shows mydriasis, rhinorrhea, and piloerection. A drug is administered that provides an effect similar to oxycodone but does not cause euphoria. Which of the following best explains the difference in effect?", "answer": "Lower efficacy", "options": {"A": "Lower bioavailability", "B": "Lower potency", "C": "Lower efficacy", "D": "Lower affinity", "E": "Lower tolerance"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-year-old girl is brought to a clinic with complaints of fever and sore throat for 2 days. This morning, she developed a rash on her face and neck which is progressing towards the trunk. The teachers in her school report that none of her classmates has similar symptoms. She has a normal birth history. On physical examination, the child looks healthy. The heart rate is 90/min, respiratory rate is 20/min, temperature is 39.0°C (102.2°F), and blood pressure is 90/50 mm Hg. An oropharyngeal examination reveals circumoral pallor with a red tongue, as shown in the photograph below. The chest and cardiac examinations are within normal limits. No hepatosplenomegaly is noted. What is the most likely diagnosis?", "answer": "Scarlet fever", "options": {"A": "Scarlet fever", "B": "Erythema Infectiosum", "C": "Kawasaki disease", "D": "Roseola", "E": "Measles"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-day-old healthy male infant is born with normal internal and external male reproductive organs. Karyotype analysis reveals a 46XY genotype. Production of what substance by which cell type is responsible for the development of the normal male seminal vesicles, epididymides, ejaculatory ducts, and ductus deferens?", "answer": "Testosterone; Leydig cells", "options": {"A": "Testis-determining factor; Sertoli cells", "B": "Testis-determining factor; Leydig cells", "C": "Testosterone; Sertoli cells", "D": "Testosterone; Leydig cells", "E": "Mullerian inhibitory factor; Sertoli cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old man presents to his primary care physician with 3 months of increasing fatigue. He says that he has been feeling short of breath while walking to his office from the parking lot and is no longer able to participate in recreational activities that he enjoys such as hiking. His wife also comments that he has been looking very pale even though they spend a lot of time outdoors. His past medical history is significant for acute kidney injury after losing blood during a car accident as well as alcoholic hepatitis. Physical exam reveals conjunctival pallor, and a peripheral blood smear is obtained with the finding demonstrate in figure A. Which of the following is associated with the most likely cause of this patient's symptoms?", "answer": "Increased production of platelet derived growth factor", "options": {"A": "Abnormal triglyceride handling", "B": "Increased production of platelet derived growth factor", "C": "Inhibition of metalloproteinase activity", "D": "Mutation in cytoskeletal proteins", "E": "Mutation in glycolysis pathway protein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old man is referred to the outpatient psychiatry clinic for depressed mood. He was diagnosed with pancreatic cancer recently. Since then, he has not been able to go to work. Over the past several weeks, he has had significant unintentional weight loss and several bouts of epigastric pain. He lost his father to cancer when he was 10 years old. After a complete history and physical examination, the patient is diagnosed with major depressive disorder, provisional. Which of the following statements regarding this patient’s psychiatric condition is true?", "answer": "This patient must have anhedonia or depressed mood.", "options": {"A": "This patient must have anhedonia or depressed mood.", "B": "This patient may have a history of elated mood.", "C": "This patient has preserved social and occupational functioning.", "D": "This patient may have pressured speech.", "E": "This patient’s symptoms must have been present for at least 1 month."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old man is admitted to the intensive care unit after open abdominal aortic aneurysm repair. The patient has received 4 units of packed red blood cells during the surgery. During the first 24 hours following the procedure, he has only passed 200 mL of urine. He has congestive heart failure and hypertension. Current medications include atenolol, enalapril, and spironolactone. He appears ill. His temperature is 37.1°C (98.8°F), pulse is 110/min, respirations are 18/min, and blood pressure is 110/78 mm Hg. Examination shows dry mucous membranes and flat neck veins. The remainder of the examination shows no abnormalities. Laboratory studies show a serum creatinine level of 2.0 mg/dL and a BUN of 48 mg/dL. His serum creatinine and BUN on admission were 1.2 mg/dL and 18 mg/dL, respectively. Further evaluation of this patient is most likely to reveal which of the following findings?", "answer": "Low urine sodium", "options": {"A": "Decreased urine osmolarity", "B": "Leukocyte casts", "C": "Hematuria", "D": "Low urine sodium", "E": "Proteinuria"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought to the physician by his parents because of 2 episodes of screaming in the night over the past week. The parents report that their son woke up suddenly screaming, crying, and aggressively kicking his legs around both times. The episodes lasted several minutes and were accompanied by sweating and fast breathing. The parents state that they were unable to stop the episodes and that their son simply went back to sleep when the episodes were over. The patient cannot recall any details of these incidents. He has a history of obstructive sleep apnea. He takes no medications. His vital signs are within normal limits. Physical examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Sleep terror disorder", "options": {"A": "Insomnia disorder", "B": "Restless legs syndrome", "C": "Sleep terror disorder", "D": "Nightmare disorder", "E": "Sleepwalking disorder"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old boy is brought to the pediatrician by his mother for fatigue. The patient reports that he was supposed to try out for winter track this year, but he had to quit because his “legs just give up.” He also reports increased difficulty breathing with exercise but denies chest pain or palpitations. He has no chronic medical conditions and takes no medications. He has had no surgeries in the past. The mother reports that he met all his pediatric milestones and is an “average” student. He is up-to-date on all childhood vaccinations, including a recent flu vaccine. On physical examination, there is mild lumbar lordosis. The patient’s thighs appear thin in diameter compared to his lower leg muscles, and he walks on his toes. An electrocardiogram shows 1st degree atrioventricular nodal block. Which of the following is the most likely cause of the patient’s condition?", "answer": "Abnormal dystrophin", "options": {"A": "Abnormal dystrophin", "B": "Absent dystrophin", "C": "Peripheral nerve demyelination", "D": "Sarcomere protein dysfunction", "E": "Trinucleotide repeats"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An otherwise healthy 1-month-old girl is brought to the physician because of a 1-day history of multiple episodes of bilious vomiting. She is diagnosed with intestinal malrotation and volvulus and undergoes emergency laparotomy. During surgery, a 3 x 3 cm cystic mass is excised from behind the umbilicus. Microscopic examination of the mass shows mature nonciliated columnar epithelium with some goblet cells lining the inner cyst wall. Dilation of which of the following structures is the most likely cause of this patient's mass?", "answer": "Vitelline duct", "options": {"A": "Urachus", "B": "Umbilical ring", "C": "Vitelline duct", "D": "Ovarian follicle", "E": "Common bile duct"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 34-year-old woman comes to the emergency department because of right flank pain and vomiting for 5 hours. She has had fever and chills for the past 2 days. She attended a barbecue 3 days ago, where she ate egg salad. She underwent surgery for left ovarian torsion a year ago. Menses occur at regular 28-day intervals and last 5 days. She is sexually active with 2 male partners and uses condoms inconsistently. Her only medication is an oral contraceptive pill. She is 163 cm (5 ft 4 in) tall and weighs 72.5 kg (160 lb); BMI is 27.5 kg/m2. She appears uncomfortable. Her temperature is 38.9°C (102°F), pulse is 101/min, and blood pressure is 118/76 mm Hg. The lungs are clear to auscultation. The right lower quadrant and right flank show severe tenderness to palpation. Pelvic examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12.8 g/dL\nLeukocyte count 14,200/mm3\nPlatelet count 230,000/mm3\nSerum\nNa+ 136 mEq/L\nK+ 3.8 mEq/L\nCl- 103 mEq/L\nUrea nitrogen 23 mg/dL\nCreatinine 1.2 mg/dL\nUrine\nBlood 1+\nProtein 1+\nGlucose negative\nLeukocyte esterase positive\nNitrites negative\nRBC 6–8/hpf\nWBC 80–85/hpf\nWhich of the following is the most likely diagnosis?\"", "answer": "Pyelonephritis", "options": {"A": "Ovarian torsion", "B": "Gastroenteritis", "C": "Urethritis", "D": "Pelvic inflammatory disease", "E": "Pyelonephritis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 5-year-old boy is brought to the pediatrician by his mother for a recurring cough and difficult breathing. He was tentatively diagnosed with asthma last year, and the mother was advised to administer albuterol nebulizers at home when symptoms occur. The boy has only required nebulizers once every 10 days. The mother says his cough is usually accompanied by a prominent wheeze and nebulizers have not been of much help. On examination, the child appears lethargic. His trachea is slightly deviated to the right, and auscultation of the chest reveals diminished breath sounds with a unilateral wheeze on the right. Which of the following pulmonary flow-volume loops best represents this patient’s most likely condition?", "answer": "Chart C", "options": {"A": "Chart A", "B": "Chart B", "C": "Chart C", "D": "Chart D", "E": "Chart E"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 74-year-old African-American woman is brought to the emergency department by her home health aid. The patient was eating breakfast this morning when she suddenly was unable to lift her spoon with her right hand. She attempted to get up from the table, but her right leg felt weak. One hour later in the emergency department, her strength is 0/5 in the right upper and right lower extremities. Strength is normal in her left upper and lower extremities. Sensation is normal bilaterally. An emergency CT of the head does not show signs of hemorrhage. Subsequent brain MRI shows an infarct involving the internal capsule. Which of the following is true about her disease process?", "answer": "The most important risk factors are hypertension and diabetes", "options": {"A": "The most important risk factors are hypertension and diabetes", "B": "The most common cause is embolism originating from the left atrium", "C": "It is caused by ischemia to watershed areas", "D": "IV thrombolysis cannot be used", "E": "The most important risk factors are ethnicity and sex"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old male presents to your office for follow-up after an upper gastrointestinal (GI) endoscopy revealed the presence of esophageal varices. His medical history is significant for cirrhosis caused by heavy alcohol abuse for the past 20 years. He was instructed to follow-up with his primary care physician for management of his condition. Which of the following is the most appropriate next step for prevention of future variceal bleeding?", "answer": "Nadolol", "options": {"A": "Careful observation", "B": "Octreotide", "C": "Nadolol", "D": "Isosorbide mononitrate", "E": "Transjugular intrahepatic portosystemic shunt"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3-year-old boy is taken to the ER by his parents due to his elevated temperature. He has had a fever (>101.1 deg F) for a little over a week, and over that time, his parents noticed his eyes had gotten a little pink, and his palms and soles were red and swollen. His lips and tongue are also peeling. His parents note he has not taken any new medications, and they did not notice any runny nose, sore throat, cough, or changes in his bowel or bladder habits. In the ER, his vitals are as follows: temperature is 101.3 deg F (38.5 deg C), blood pressure is 90/60 mmHg, pulse is 125/min, and respirations are 20/min. His exam is notable for bilateral injected conjunctivae, right-sided cervical lymphadenopathy, erythematous and edematous palms and soles, and erythema multiforme-like rash over his trunk. Appropriate lab tests and imaging were performed. Which of the following is the most worrisome complication of this boy's disease process?", "answer": "Coronary artery aneurysms", "options": {"A": "Digital gangrene", "B": "Coronary artery aneurysms", "C": "Glomerulonephritis", "D": "Endocardial valve damage", "E": "Toxic endodermal necrolysis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old woman seeks evaluation at a local walk-in clinic for severe lower abdominal pain, vaginal discharge, and painful intercourse for the last couple of weeks. Her last day of menstruation was 1 week ago, and since then the pain has worsened. She is an out-of-town college student engaged in an open relationship with a fellow classmate and another partner from her hometown. Additional concerns include painful micturition and a low-grade fever for the same duration. The physical examination reveals a heart rate of 120/min, respiratory rate of 24/min, and temperature of 38.6°C (101.5°F). The pelvic examination shows an erythematous cervix with a mucopurulent exudate. The cervix bleeds when manipulated with a swab and is extremely tender with movement. Based on the clinical findings, which of the following agents is the most likely cause of her condition?", "answer": "Neisseria gonorrhoeae", "options": {"A": "Neisseria gonorrhoeae", "B": "Mycobacterium tuberculosis", "C": "Mycoplasma genitalium", "D": "Streptococcus agalactiae", "E": "Chlamydia trachomatis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old man comes to the physician because of a rash on the thigh for 10 days. He reports that the rash has been enlarging and is intensely itchy. Two weeks ago, he adopted a stray dog from an animal shelter. Vital signs are within normal limits. A photograph of the examination findings is shown. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Dermatophyte infection", "options": {"A": "Psoriasis", "B": "Erythrasma", "C": "Pityriasis rosea", "D": "Dermatophyte infection", "E": "Tinea versicolor"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old man with hypertension comes to the physician for a routine follow-up evaluation. His blood pressure is 146/98 mm Hg. The physician wishes to prescribe lisinopril. The patient says that his blood pressure is high when he is “anxious” and requests alprazolam instead of lisinopril. Which of the following is the most appropriate initial response by the physician?", "answer": "“What have you heard about the use of alprazolam to treat high blood pressure?”", "options": {"A": "“I would recommend fluoxetine because alprazolam can cause dependence.”", "B": "“I would recommend consultation with a psychiatrist.”", "C": "“Anxiety can cause temporary spikes in blood pressure, but it does not cause a long-term increase in blood pressure.”", "D": "“What have you heard about the use of alprazolam to treat high blood pressure?”", "E": "“Lisinopril is more effective to treat hypertension. If you do not control your high blood pressure, you may develop a stroke.”"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 78-year-old right-handed male is brought in by ambulance after being found down in his home. After being aroused, the patient has difficulty answering questions and appears to be frustrated by his inability to communicate. He is able to speak his name and a few other words but his speech is not fluent. Subsequent neurologic exam finds that the patient is able to comprehend both one and two step instructions; however, he is unable to repeat phrases despite being able to understand them. He also has difficulty writing despite retaining fine motor control. CT reveals an acute stroke to his left hemisphere. Damage to which of the following sets of structures would be most likely to result in this pattern of deficits?", "answer": "Inferior frontal gyrus", "options": {"A": "Inferior frontal gyrus", "B": "Superior temporal gyrus", "C": "Arcuate fasciculus", "D": "Watershed zone", "E": "Precentral gyrus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 66-year-old man presents to the emergency department for a 1-hour history of right arm weakness. He was having breakfast this morning when his right arm suddenly became weak, causing him to drop his coffee mug. He also noticed that he was slurring his speech and had some additional weakness in his right leg. He had no symptoms prior to the onset of the weakness and noted no other unusual phenomena. These symptoms lasted for about 30 minutes, but they resolved completely by the time he arrived at the emergency department. His medical history is notable for hypertension and hyperlipidemia, but he does not receive close follow-up from a primary care physician for these conditions. The patient currently is not taking any medications. His pulse is 75/min, the blood pressure is 160/95 mm Hg, and the respiratory rate is 14/min. Physical exam is remarkable for a high-pitched sound heard on auscultation of the neck, the remainder of the exam, including a complete neurological exam, is entirely unremarkable. CT angiography of the head and neck shows no active hemorrhage and 80% stenosis of the left internal carotid artery. Which of the following is the next best step in the long-term management of this patient?", "answer": "Carotid endarterectomy", "options": {"A": "Carotid endarterectomy", "B": "Administration of tissue plasminogen activator (tPA)", "C": "Brain MRI", "D": "Initiation of aspirin and atorvastatinInitiation of aspirin and atorvastatin", "E": "Initiation of lisinopril"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old woman is seen in the hospital for neutropenic fever. She was admitted 1 week ago for newly diagnosed acute myeloid leukemia. Due to her chemotherapy, she became pancytopenic. Last night, during a packed red blood cell transfusion, she became febrile to 102.6°F (39.3°C), her blood pressure was 92/55, pulse was 112/min, respirations were 16/min, and oxygen saturation was 94% on room air. The transfusion was stopped, intravenous fluids were started, and blood cultures were drawn. The patient also complained of chest pain and shortness of breath. A chest radiograph was obtained and was normal. This morning, she reports “dark urine” but denies dysuria or abnormal vaginal discharge. Her prophylactic antimicrobials started at the time of her chemotherapy include acyclovir, levofloxacin, and fluconazole. The patient’s temperature this morning is 98.7°F (37.1°C), blood pressure is 110/72 mmHg, pulse is 88/min, and respirations are 17/min with an oxygen saturation of 95% on room air. On physical examination, she has 1+ pitting peripheral edema of bilateral lower extremities to the mid-shin. Her jugular venous pressure is 6 cm. Her labs show neutropenia, normocytic anemia, thrombocytopenia, elevated lactose dehydrogenase, elevated total bilirubin, and decreased haptoglobin. Coagulation studies show an increase in bleeding time with normal D-dimer levels. Which of the following is the most likely cause of the patient’s symptoms?", "answer": "ABO incompatibility", "options": {"A": "ABO incompatibility", "B": "Disseminated intravascular coagulation", "C": "Severe urosepsis", "D": "Transfusion associated circulatory overload", "E": "Transfusion related acute lung injury"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old African-American boy presents with a rapid onset of severe abdominal pain. He has a palpably enlarged mass in the left upper quadrant of his abdomen. Complete blood count is notable for a hemoglobin of 7.2 g/dL. Serum haptoglobin level returns normal. Serum unconjugated bilirubin is elevated. The corrected reticulocyte count is elevated. Which of the following is the most likely explanation for the findings above?", "answer": "Extravascular hemolysis", "options": {"A": "Aplastic crisis", "B": "Acute chest syndrome", "C": "Renal infarction", "D": "Intravascular hemolysis", "E": "Extravascular hemolysis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old man comes to the physician because of a persistent cough for the past 2 weeks. During this time, he has also had occasional discomfort in his chest. Three weeks ago, he had a sore throat, headache, and a low-grade fever, which were treated with acetaminophen and rest. He has a history of hypertension and hyperlipidemia. His father died of myocardial infarction at the age of 57 years. He has smoked a pack of cigarettes daily for the past 40 years. Current medications include enalapril and atorvastatin. His temperature is 37°C (98.6°F), pulse is 70/min, and blood pressure is 145/90 mm Hg. Physical examination shows no abnormalities. An x-ray of the chest is shown. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the chest", "options": {"A": "Esophageal manometry", "B": "CT scan of the chest", "C": "Arteriography", "D": "Genetic testing", "E": "Endovascular repair"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 31-year-old male with cirrhosis, dementia, and Parkinson-like symptoms is diagnosed with a hereditary metabolic disease resulting from the accumulation of a certain metal in various tissues. Impairment of which of the following elimination pathways is most likely responsible?", "answer": "Secretion into bile", "options": {"A": "Secretion into bile", "B": "Loop of Henle secretion into lumen of kidney", "C": "Glomerular filtration", "D": "Bleeding", "E": "Duodenal secretion"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An x-ray of the chest shows an extensive consolidation within the right lower lobe consistent with lobar pneumonia. Sputum and blood cultures are sent to the laboratory for analysis, and empiric antibiotic treatment with intravenous cefotaxime is begun. Which of the following is most likely to have prevented this patient's pneumonia?", "answer": "Incentive spirometry", "options": {"A": "Incentive spirometry", "B": "Rapid sequence induction", "C": "Prolonged bed rest", "D": "Perioperative antibiotic prophylaxis", "E": "Smoking cessation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 58-year-old man with history of diabetes and hypertension suffers a cardiac arrest at home. The family calls 911, yet no one performs CPR. Five minutes after the arrest, EMS arrives to begin resuscitation. At this point, which region of the CNS is most likely to suffer ischemic damage?", "answer": "Hippocampus", "options": {"A": "Thalamus", "B": "Spinal cord", "C": "Pons", "D": "Medulla", "E": "Hippocampus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 77-year-old man with type 2 diabetes mellitus is admitted to the hospital because of chest pain and dyspnea. Serum troponin levels are elevated and an ECG shows ST-segment depressions in the lateral leads. Percutaneous coronary angiography is performed and occlusion of the distal left anterior descending coronary artery is identified. Pharmacotherapy with eptifibatide is initiated and a drug-eluting stent is placed in the left anterior descending coronary artery. The mechanism by which eptifibatide acts is similar to the underlying pathophysiology of which of the following conditions?", "answer": "Glanzmann thrombasthenia", "options": {"A": "Von Willebrand disease", "B": "Vitamin K deficiency", "C": "Protein C deficiency", "D": "Thrombotic thrombocytopenic purpura", "E": "Glanzmann thrombasthenia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 66-year-old man comes to the physician for a follow-up examination after a below-knee amputation of the right lower leg. Three weeks ago, he had an acute arterial embolism that could not be revascularized in time to save the leg. He now reports episodic hot, shooting, and tingling pain in the right lower leg that began shortly after the amputation. He has type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for the past 30 years. His current medications are metformin and prophylactic subcutaneous heparin. His temperature is 37.1°C (98.8°F), pulse is 78/min, and blood pressure is 135/88 mm Hg. Physical examination shows a slightly erythematous stump with clean sutures. The skin overlying the stump is warm and well-perfused. Muscle strength and sensation are normal throughout the remaining extremity and the left lower extremity. Which of the following is the most likely diagnosis?", "answer": "Phantom limb pain", "options": {"A": "Phantom limb pain", "B": "Foreign body reaction", "C": "Reinfarction", "D": "Diabetic neuropathy", "E": "Osteomyelitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Four days after undergoing liver transplantation, a 47-year-old man develops fever, chills, malaise, and confusion while in the intensive care unit. His temperature is 39.1°C (102.4°F). Blood cultures grow an organism. Microscopic examination of this organism after incubation at 25°C (77°F) for 3 hours is shown. Which of the following is the most likely causal organism of this patient's symptoms?", "answer": "Candida albicans", "options": {"A": "Aspergillus fumigatus", "B": "Candida albicans", "C": "Cryptococcus neoformans", "D": "Histoplasma capsulatum", "E": "Malassezia furfur"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 18-year-old man presents to his primary care provider for a routine checkup. He feels well and has no complaints. He is the captain of his high school football team and will be attending college on a football scholarship the following year. His past medical history is unremarkable. He underwent a laparoscopic appendectomy at age 13. He takes no medications and has no allergies. His temperature is 99.1°F (37.3°C), blood pressure is 155/85 mmHg, pulse is 96/min, and respirations are 16/min. On examination, he has severe nodulocystic acne. He has gained 15 pounds and 1/2 inch in height since his last visit one year ago. Mild gynecomastia and testicular shrinkage are noted. This patient is at the greatest risk of developing which of the following?", "answer": "Hepatic adenoma", "options": {"A": "Hepatic adenoma", "B": "Hepatocellular carcinoma", "C": "Renal cyst", "D": "Testicular enlargement", "E": "Type 1 diabetes mellitus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man with a 4-year history of Parkinson disease comes to the physician for evaluation of his medication. Since his last visit one year ago, he has had increased tremor and bradykinesia up to an hour before his next scheduled dose and sometimes feels like he does not respond to some doses at all. One week ago, he was entirely unable to move for about a minute when he wanted to exit an elevator. The physician prescribes a drug that increases the bioavailability of levodopa by preferentially preventing its peripheral methylation. This patient was most likely prescribed which of the following drugs by the physician?", "answer": "Entacapone", "options": {"A": "Carbidopa", "B": "Entacapone", "C": "Ropinirole", "D": "Amantadine", "E": "Rasagiline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 31-year-old woman has a follow-up visit with her psychiatrist. She was recently diagnosed with major depressive disorder and was started on citalopram 3 months ago. Her dosage was increased one time 6 weeks ago. She has come in to discuss her progress and notes that she feels “normal again” and “happier” and has not experienced her usual feelings of depression, crying spells, or insomnia. Her appetite has also improved and she is performing better at work, stating that she has more focus and motivation to complete her assignments. During the beginning of her treatment, she states that she had occasional headaches and diarrhea, but that she no longer has those side effects. Which of the following is the most appropriate next step in this patient’s management?", "answer": "Maintain the current dose of citalopram for several months", "options": {"A": "Lower the dose of citalopram", "B": "Maintain the current dose of citalopram for several months", "C": "Increase the dose of citalopram", "D": "Discontinue the citalopram", "E": "Discontinue the citalopram and switch to amitriptyline"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old construction worker presents to the emergency department two hours after sustaining a deep laceration to his left forearm by a piece of soiled and rusted sheet metal. His vital signs are stable, there is no active bleeding, his pain is well controlled, and a hand surgeon has been notified about damage to his forearm tendons. He does not recall receiving any vaccinations in the last 30 years and does not know if he was vaccinated as a child. What is the appropriate post-exposure prophylaxis?", "answer": "Tetanus vaccine + immunoglobulin", "options": {"A": "IV metronidazole only", "B": "Anthrax vaccine", "C": "Tetanus vaccine booster only", "D": "Tetanus immunglobulin only", "E": "Tetanus vaccine + immunoglobulin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 53-year-old woman presents with a feeling of pelvic pressure which worsens with prolonged standing, pain on sexual intercourse, and lower back pain. She reports no urinary or fecal incontinence. She is G3P3 with no history of any gynecological disease and is premenopausal. All pregnancies were without complication and resolved with full-term vaginal deliveries. The patient has sex with her husband who is her single sexual partner and uses oral contraceptives. Her vital signs are within normal limits and physical examination is unremarkable. A gynecological examination reveals bulging of the posterior vaginal wall in the lower portion of the vagina which increases in the upright position and Valsalva maneuver. The cervix is in its normal position. The uterus is not enlarged, ovaries are nonpalpable. Damage to which of the following structures might contribute to the patient’s condition?", "answer": "Rectovaginal fascia", "options": {"A": "Rectovaginal fascia", "B": "Cardinal ligaments", "C": "Round ligaments", "D": "Pubocervical fascia", "E": "Uterosacral ligaments"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 64-year-old woman presents to the emergency department with a 1-hour history of shortness of breath and chest pain. She said that the symptoms came on suddenly and that the chest pain is worse when she tries to take a deep breath. Her past medical history is significant for a previous deep venous thrombosis for which she was taking a blood thinner. She also has diabetes, hypertension, hyperlipidemia, and partial seizures which are treated with metformin, lisinopril, atorvastatin, and carbamazepine and valproic acid, respectively. Which of these drugs is most likely responsible for causing this patient's blood thinner medications to fail?", "answer": "Carbamazepine", "options": {"A": "Atorvastatin", "B": "Carbamazepine", "C": "Lisinopril", "D": "Metformin", "E": "Valproic acid"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "5 days after receiving chemotherapy for ovarian cancer, a 74-year-old woman comes to the physician for a follow-up examination. She feels well and has no complaints. Her leukocyte count is 3,500/mm3 (11% neutrophils and 89% lymphocytes). This patient's profound granulocytopenia is most likely to predispose her to infection with which of the following organisms?", "answer": "Enterococcus faecalis", "options": {"A": "Enterococcus faecalis", "B": "Gardnerella vaginalis", "C": "Giardia lamblia", "D": "Cytomegalovirus infection", "E": "Pneumocystis jirovecii"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old man presents to your office because he noticed a \"weird patch\" on the floor of his mouth. He states that he noticed it a few months ago, but did not report it because it did not hurt. However, he is concerned because it has not regressed and seems to have changed in shape. On examination, you notice the patient has poor dentition and he admits to using chewing tobacco daily. The patch on the floor of his mouth is red with irregular borders. Which of the following would be an appropriate way to counsel this patient on his current condition?", "answer": "This lesion necessitates biopsy.", "options": {"A": "This lesion is due to an infection.", "B": "This lesion is closely associated with chronic Hepatitis C infection.", "C": "This lesion necessitates biopsy.", "D": "This lesion carries no increased risk of cancer.", "E": "Tobacco use is not a risk factor."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old woman comes to the physician for evaluation of worsening fatigue for 1 week. She also has a 1-year history of hand pain and stiffness. Four months ago, she started a new medication for these symptoms. Medications used prior to that included ibuprofen, prednisone, and hydroxychloroquine. Examination shows a subcutaneous nodule on her left elbow and old joint destruction with Boutonniere deformity. Her hemoglobin concentration is 10.1 g/dL, leukocyte count is 3400/mm3, and platelet count is 101,000/mm3. Methylmalonic acid levels are normal. Which of the following could have prevented this patient's laboratory abnormalities?", "answer": "Leucovorin", "options": {"A": "Vitamin B6", "B": "Vitamin B12", "C": "Amifostine", "D": "2-Mercaptoethanesulfonate", "E": "Leucovorin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old previously healthy female presents to her primary care physician with double vision. She first noted the double vision yesterday and saw no improvement this morning. She does not think it is worsening. She has not had any changes in her normal routine though she recalls one episode of right arm weakness 2 months ago. She did not seek treatment and the weakness subsided after several days. She does not have a history of head trauma. She denies headache, fever, chills, nausea, vomiting, paresthesias, extremity pain, or weakness. On exam she has right adduction palsy on leftward gaze. She has no focal weakness. Which of the following additional physical exam findings is associated with the lesion responsible for her ocular findings?", "answer": "Horizontal nystagmus in the left eye on leftward gaze", "options": {"A": "Horizontal nystagmus in the left eye on leftward gaze", "B": "Ptosis on the right", "C": "Proptosis of the right eye", "D": "Left abduction palsy on leftward gaze", "E": "Afferent pupillary defect in the left eye"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A team of researchers is investigating different mechanisms of transmitting sensory information in the body. They are particularly interested in the different types of sensory receptors. From a sample of tissue, they isolate a receptor that is encased in deep skin layers and joints. The receptor adapts quickly and they discover its role is to sense vibration and pressure. Which of the following types of nerve fibers is most likely used by this receptor to transmit sensory information?", "answer": "Large, myelinated fibers", "options": {"A": "Small, unmyelinated fibers", "B": "Small, myelinated fibers", "C": "Large, unmyelinated fibers", "D": "Large, myelinated fibers", "E": "Dendritic endings"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old African American woman comes to the emergency department with intermittent and progressively worsening dizziness with near-fainting incidents for the last 3 weeks. She denies fever, weight loss, nausea, vomiting, or chest pain. Her medical history is significant for a chronic cough and intermittent skin rashes that spontaneously resolved after a few weeks. She does not smoke tobacco but drinks alcohol socially. The patient lives alone with no pets. Her temperature is 37°C (98.6°F), blood pressure is 122/80 mm Hg, pulse is 43/min, and respirations are 12/min. On physical examination, cervical lymphadenopathy is noted. No heart murmurs are heard. ECG shows sinus rhythm with 2:1 atrioventricular block and left bundle branch block. Chest X-ray shows prominent hilar lymphadenopathy. Which of the following is the most likely diagnosis?", "answer": "Sarcoidosis", "options": {"A": "Carotid artery stenosis", "B": "Cardiac myxoma", "C": "Non-Hodgkin’s lymphoma", "D": "Small cell lung cancer", "E": "Sarcoidosis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 36-year-old woman comes to the physician for evaluation of unintentional weight gain of 5.5 kg (12.2 lb) and irregular menstrual cycles over the past 2 months. She does not take any medications. Her blood pressure is 155/85 mm Hg. Physical examination shows central obesity, hyperpigmentation of the palmar creases, and violaceous scarring of the abdomen. Early morning serum cortisol levels are elevated and serum adrenocorticotropic hormone (ACTH) is within the reference range after a low-dose dexamethasone suppression test. A high-dose dexamethasone suppression test shows suppression of ACTH. Further evaluation is most likely to show which of the following findings?", "answer": "Bilateral hyperplasia of the zona fasciculata", "options": {"A": "Atrophy of the pituitary gland", "B": "Benign adenoma of the adrenal medulla", "C": "Nodular hypertrophy of the zona reticularis", "D": "Bilateral hyperplasia of the zona fasciculata", "E": "Unilateral carcinoma of the adrenal cortex"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old gentleman with a history of poorly controlled diabetes mellitus is referred to a nephrologist for evaluation of the possibility of early stage kidney failure. Upon evaluation, the nephrologist decides to assess the patient's renal plasma flow by performing a laboratory test. Which of the following substances would be the best for estimating this value?", "answer": "Para-aminohippurate (PAH)", "options": {"A": "Creatinine", "B": "Inulin", "C": "Glucose", "D": "Para-aminohippurate (PAH)", "E": "Urea"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old woman comes to the physician because of a 2-week history of malaise, nausea, and a 3-kg (6.6-lb) weight loss. She has been drinking 8–9 alcoholic beverages daily for the past 20 years. Her temperature is 37.8°C (100°F) and pulse is 105/min. Examination shows jaundice and hepatosplenomegaly. A photomicrograph of a section of a biopsy specimen of the liver is shown. Which of the following mechanisms best explains the findings shown?", "answer": "Increased glycerol 3-phosphate formation", "options": {"A": "Excessive interstitial TGF-β activity", "B": "Decreased clearance of N-acetyl-p-benzoquinone imine", "C": "Intracellular accumulation of lactate", "D": "Increased glycerol 3-phosphate formation", "E": "Estrogen-mediated glandular hyperplasia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old female with a history of hypertension, type II diabetes mellitus, hypothyroidism, and asthma undergoes a scheduled total abdominal hysterectomy for symptomatic fibroids. She is given a dose of preoperative prophylactic antibiotics. Her urinary catheter is removed on post-operative day one. She is on low-molecular-weight heparin for deep vein thrombosis prophylaxis. On post-operative day four, the patient complains of abdominal pain. She denies cough, nausea, vomiting, or dysuria, but has had 3-4 loose stools over her hospitalization. Her temperature is 101.0°F (38.3°C), blood pressure is 97/59 mmHg, pulse is 106/min, and respirations are 16/min. The surgical wound has new erythema with dusky patches and abundant cloudy discharge. The patient reports new decreased sensation around her wound site. Her lungs are clear to auscultation and abdomen is soft with hypoactive bowel sounds. She has no costovertebral angle tenderness. Urinalysis is within normal limits and urine culture grows >100,000 CFU/mL of Escherichia coli.\n\nWhich of the following is the best next step in management?", "answer": "Vancomycin/piperacillin-tazobactam/clindamycin and debridement of the surgical wound", "options": {"A": "Discontinue low-molecular-weight heparin", "B": "Oral levofloxacin for 3 days", "C": "Oral vancomycin for 10-14 days", "D": "Vancomycin/piperacillin-tazobactam/clindamycin and observation", "E": "Vancomycin/piperacillin-tazobactam/clindamycin and debridement of the surgical wound"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 1-month-old boy is brought to the emergency department 25 minutes after having a seizure. His mother reports that he has become lethargic and does not cry as vigorously anymore. Examination shows muscular hypotonia and hepatomegaly. Arterial blood gas on room air shows metabolic acidosis. Serum studies show elevated levels of methylmalonic acid. A deficiency of which of the following types of enzymes is the most likely cause of this patient's condition?", "answer": "Mutase", "options": {"A": "Phosphorylase", "B": "Phosphatase", "C": "Carboxylase", "D": "Hydroxylase", "E": "Mutase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 22-year-old patient presents to the rural medicine clinic for a physical examination. She has a past medical history of major depressive disorder. The patient has a history of smoking 1 pack of cigarettes daily for 5 years. She states that she is not currently sexually active, but had sexual intercourse in the past. Her paternal grandfather died of a heart attack at the age of 60. She takes citalopram by mouth once every morning. The blood pressure is 110/70 mm Hg, the heart rate is 76/min, and the respiratory rate is 12/min. Her physical examination reveals a well-nourished, alert, and oriented female. While auscultating the heart, a 2/6 holosystolic murmur at the left upper sternal border is present. Which of the following would be the most appropriate next step for this patient?", "answer": "Pap smear", "options": {"A": "Pap smear", "B": "Pap smear and HPV testing", "C": "Colposcopy and biopsy", "D": "Education on breast self-examinations", "E": "Screening for hyperlipidemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 66-year-old homeless HIV-positive male presents with numbness in his hands and feet. The patient says that his symptoms started gradually a couple weeks ago and have slowly worsened. He describes numbness initially in just his fingertips and toes but it has now spread to involve his entire hands and feet. Past medical history is significant for HIV diagnosed many years ago, for which the patient has never sought treatment. The patient also has a long history of various illnesses, especially chronic diarrhea, but he is unable to remember any details. He currently takes no medications. The patient has been homeless for years, and he denies any alcohol or drug use. Review of systems is significant for a sore tongue. His temperature is 37°C (98.6°F), blood pressure is 100/65 mm Hg, pulse is 102/min, respiratory rate is 25/min, and oxygen saturation is 97% on room air. On physical exam, the patient is alert and oriented, his body habitus is cachectic, and his BMI is 17 kg/m2. His tongue appears erythematous and smooth with loss of papillae, but no lesions or evidence of infection is noted. Cardiac exam is normal apart from tachycardia. Lungs are clear to auscultation. His abdomen is soft and nontender with no hepatosplenomegaly. There is decreased 2-point discrimination in the hands and feet bilaterally. Strength in the hands and feet is 4/5 bilaterally. Reflexes are absent in the ankles. Gait is slightly wide-based and ataxic, and there is a positive Romberg sign. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Elevated levels of methylmalonic acid (MMA)", "options": {"A": "Elevated levels of methylmalonic acid (MMA)", "B": "Poorly controlled, undiagnosed diabetes", "C": "Autoimmune reaction", "D": "Disseminated bacterial infection", "E": "Deposition of an insoluble protein"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old woman presents to the emergency department in a frantic state and demands immediate treatment for an allergic reaction, which started soon after she had lunch (approximately 1 hour ago). She had her usual meal consisting of homemade salad and lemonade. She was recently started on niacin because she could not tolerate statins. The only other medication she takes is captopril for hypertension. She has no respiratory difficulty and denies rhinorrhea, epiphora, and diarrhea. She is complaining of a stinging sensation on her face. She has no history of allergies and no family history of allergies. The vital signs include: pulse 90/min, respirations 16/min, blood pressure 120/80 mm Hg, and oxygen saturation, 98% on room air. On physical examination, the face and trunk have a flushed appearance. The rest of the physical examination is unremarkable. The attending physician reassures her that she is not in any immediate danger, and in fact, her symptoms subsided over the next hour. She is advised to take aspirin 30 minutes before her other medications and sent home. Which of the following is the etiology of her symptoms?", "answer": "Prostaglandin release", "options": {"A": "Anxiety", "B": "Drug overdose", "C": "A mild allergic reaction", "D": "Prostaglandin release", "E": "Serotonin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old man comes to the physician for 2 months of intermittent low-grade fever, malaise, and joint pain. He has a history of recurrent dental abscesses requiring drainage but has otherwise been healthy. His temperature is 38.3°C (100.9°F) and pulse is 112/min. Physical examination shows a new holosystolic murmur in the left midclavicular line that radiates to the axilla. There are linear reddish-brown lesions underneath the nail beds and tender violaceous nodules on the bilateral thenar eminences. Two sets of blood cultures grow Streptococcus mutans. A transthoracic echocardiogram shows moderate regurgitation of the mitral valve. Which of the following mechanisms is most likely directly involved in the pathogenesis of this patient's valvular condition?", "answer": "Fibrin clot formation", "options": {"A": "Antibody cross-reaction", "B": "Sterile platelet thrombi deposition", "C": "Leaflet calcification and fibrosis", "D": "Coagulative necrosis", "E": "Fibrin clot formation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-year-old boy is brought to the physician by his mother because of painless lesions on his face that he has had since shortly after birth. They recently moved to the USA from Indonesia where they had limited access to healthcare. A photograph of the lesions is shown. Which of the following is the most likely diagnosis?", "answer": "Infantile hemangioma", "options": {"A": "Infantile hemangioma", "B": "Verruca vulgaris", "C": "Neurofibromas", "D": "Spider angioma", "E": "Molluscum contagiosum"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 30-year-old man is diagnosed with multi-drug resistant tuberculosis after a recent trip to Eastern Europe. After drug susceptibility testing is completed, he is given a regimen of antibiotics as treatment. He returns two weeks later complaining of decreased visual acuity and color-blindness. Which drug of the following is the mechanism of action of the drug that is most likely to cause this side effect?", "answer": "Inhibition of arabinogalactan synthesis", "options": {"A": "Inhibition of mycolic acid synthesis", "B": "Inhibition of arabinogalactan synthesis", "C": "Binding to ergosterol and formation of a transmembrane channel", "D": "Inhibition of RNA synthesis", "E": "Inhibition of RNA translation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old boy is brought to the physician because of intermittent abdominal cramps and recurrent episodes of foul-smelling greasy diarrhea for 3 months. He has a history of recurrent upper respiratory infection. The abdomen is diffusely tender to palpation and resonant to percussion. A photomicrograph of a stool sample is shown. This patient is at increased risk for which of the following?", "answer": "Hypersensitivity reaction to transfusion", "options": {"A": "Hypersensitivity reaction to transfusion", "B": "Gastric adenocarcinoma", "C": "Progressive peripheral neuropathy", "D": "Cutaneous granulomas", "E": "Disseminated tuberculosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 23-year-old man comes to the emergency department for 2 days of severe headaches. The pain is most intense on his left forehead and eye. He had similar symptoms last summer. He has been taking indomethacin every 6 hours for the last 24 hours but has not had any relief. He has smoked 1 pack of cigarettes daily for the past 5 years. He works as an accountant and describes his work as very stressful. Physical examination shows drooping of the left eyelid, tearing of the left eye, and rhinorrhea. The left pupil is 2 mm and the right pupil is 4 mm. There is localized tenderness along the right supraspinatus muscle. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Cluster headache", "options": {"A": "Giant cell arteritis", "B": "Medication overuse headache", "C": "Cluster headache", "D": "Trigeminal neuralgia", "E": "Tension headache"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A research group wants to assess the relationship between childhood diet and cardiovascular disease in adulthood. A prospective cohort study of 500 children between 10 to 15 years of age is conducted in which the participants' diets are recorded for 1 year and then the patients are assessed 20 years later for the presence of cardiovascular disease. A statistically significant association is found between childhood consumption of vegetables and decreased risk of hyperlipidemia and exercise tolerance. When these findings are submitted to a scientific journal, a peer reviewer comments that the researchers did not discuss the study's validity. Which of the following additional analyses would most likely address the concerns about this study's design?", "answer": "Stratification", "options": {"A": "Blinding", "B": "Crossover", "C": "Matching", "D": "Stratification", "E": "Randomization"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old male with Down syndrome is brought to your clinic by his mother. She reports that over the past few months he has started having difficulty managing his daily routine at his assisted-living facility and no longer seems like himself. She says that last week he wandered away from the facility and was brought back by police. Additionally, he has stopped taking his regular antiepileptic medication, and she is concerned that he might have a seizure. TSH is checked and is normal. Which of the following is most likely to be responsible for this man's current presentation?", "answer": "Abnormal protein metabolism", "options": {"A": "Expansion of trinucleotide repeats", "B": "Abnormal protein metabolism", "C": "Hormone deficiency", "D": "Premature degradation of a protein", "E": "Nutritional deficiency"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 14-year-old Caucasian male patient found to have low serum copper, high urine copper, and low serum ceruloplasmin is placed on penicillamine for management of his genetic disorder. Which of the following is LEAST consistent with this patient's clinical picture?", "answer": "Kinky, easily breakable hair", "options": {"A": "Kinky, easily breakable hair", "B": "Cirrhosis", "C": "Hemiballismus", "D": "Corneal deposits", "E": "Parkinson-like symptoms"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 59-year-old man is brought to the emergency department 30 minutes after having a seizure. His wife reports that the patient has been having recurrent headaches and has become increasingly irritable over the past 3 months. Physical examination shows a spastic paresis of the right lower extremity. The Babinski sign is present on the right side. An MRI of the brain is shown. Which of the following is the most likely diagnosis?", "answer": "Meningioma", "options": {"A": "Pituitary adenoma", "B": "Metastatic brain tumor", "C": "Ependymoma", "D": "Oligodendroglioma", "E": "Meningioma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A high-throughput screen to identify new sympathomimetic compounds was developed such that a transgenic line of cells was created that contained the alpha-1 (red), alpha-2 (yellow), beta-1 (green) and beta-2 (blue) receptors. When each of the receptors was activated a different fluorescent protein was expressed and new compounds with different properties could be identified by the fluorescence that they induced. Compound 7583 selectively induced the expression of the blue fluorescent protein. Which of the following known sympathomimetic medications if administered would similarly result in expression of only the blue fluorescent protein?", "answer": "Albuterol", "options": {"A": "Albuterol", "B": "Midrodrine", "C": "Epinephrine", "D": "Isoproterenol", "E": "Fenoldopam"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 53-year-old man is brought by his daughter to the clinic. She lives a town away but visits often. She reports that on recent visits, his mood has been volatile, ranging from aggressive at some moments to depressed at others. She has noticed some new jerky movements which she has never seen before and has been quite forgetful. She is concerned that he might be abusing alcohol and drugs. What changes would you expect in the brain of this patient?", "answer": "Decreased GABA at the caudate", "options": {"A": "Increased norepinephrine at the locus ceruleus", "B": "Increased acetylcholine at the caudate", "C": "Decreased seratonin at the raphe nucleus", "D": "Decreased GABA at the caudate", "E": "Decreased dopamine at the ventral tegmentum and substantia nigra pars compacta"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A male newborn is delivered at term to a 30-year-old woman. Pregnancy and delivery were uncomplicated. At birth, the umbilical cord is noted to be large. When the newborn cries, straw-colored fluid leaks from the umbilicus. The external genitalia appear normal. Which of the following is the most likely cause of this newborn's symptoms?", "answer": "Failed obliteration of an allantoic remnant", "options": {"A": "Abnormal fusion of the urethral folds", "B": "Failed closure of the vitelline duct", "C": "Failed obliteration of an allantoic remnant", "D": "Infection of the umbilical cord stump", "E": "Malformation of the medial umbilical ligament"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A medical student is performing research on the properties of viruses in order to determine the transmission patterns of various organisms. He accidentally drops a rack of tubes and spills various virus samples on the benchtop. Upon seeing this, the laboratory technician wipes down the workbench with alcohol in order to clean up the spill. Which of the following organisms would most likely still be alive after this cleaning?", "answer": "Adenovirus and rhinovirus", "options": {"A": "Adenovirus and coronavirus", "B": "Adenovirus and herpesvirus", "C": "Adenovirus and rhinovirus", "D": "Coronavirus and herpesvirus", "E": "Coronavirus and rhinovirus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 3-year-old boy is brought in to his pediatrician by his mother after she noticed that the child was starting to turn yellow. She has not noticed any behavioral changes. On exam, the boy is icteric but is behaving normally. His temperature is 98.8°F (37.1°C), blood pressure is 108/78 mmHg, pulse is 78/min, and respirations are 14/min. His labs are drawn, and he is found to have an unconjugated hyperbilirubinemia with a serum bilirubin of 15 mg/dL. The mother is counseled that this boy’s condition may require phenobarbital as a treatment to reduce his bilirubin levels. Which of the following is the most likely defect in this child?", "answer": "Reduced UDP-glucuronosyltransferase activity", "options": {"A": "Absent UDP-glucuronosyltransferase activity", "B": "Defective liver excretion of bilirubin due to ABCC2 mutation", "C": "Defective liver excretion of bilirubin due to SLCO1B1 and SLCO1B3 mutations", "D": "Impaired bilirubin uptake", "E": "Reduced UDP-glucuronosyltransferase activity"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old woman presents to the emergency department after developing a widespread rash when she was playing in the park. She states she feels somewhat light-headed. She is otherwise healthy and has no significant past medical history. Her temperature is 97.0°F (36.1°C), blood pressure is 84/54 mmHg, pulse is 130/min, respirations are 22/min, and oxygen saturation is 95% on room air. Physical exam is notable for bilateral wheezing and a diffuse urticarial rash. Which of the following is the next best step in management?", "answer": "Epinephrine", "options": {"A": "Albuterol", "B": "Continuous monitoring", "C": "Diphenhydramine", "D": "Epinephrine", "E": "Normal saline"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old woman with rheumatoid arthritis comes to the physician because of a 3-month history of worsening fatigue and dyspnea. She has felt short-of-breath when walking up the stairs to her apartment. Menopause occurred 5 years ago. Her medications are methotrexate and folic acid supplementation. Physical examination shows conjunctival pallor, tenderness of bilateral wrists and knees, and ulnar deviation of the fingers. Her hematocrit is 27%, mean corpuscular volume is 84 μm3, and serum ferritin is 375 ng/mL. Which of the following has most likely contributed to the patient's current symptoms?", "answer": "Increased release of hepcidin by hepatocytes", "options": {"A": "Increased activity of ferroportin-1 in enterocytes", "B": "Increased release of iron from macrophages", "C": "Increased release of hepcidin by hepatocytes", "D": "Increased production of reticulocytes in bone marrow", "E": "Increased concentration of transferrin in serum"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man presents with complaints of weakness and swollen gums for the past 3 weeks. He also says he cut his finger while cooking, and the bleeding took more than 10 minutes to stop. He has a family history of diabetes mellitus type 2 and prostate cancer. Current medications are multivitamin. His blood pressure is 122/67 mm Hg, the respiratory rate is 13/min, and the temperature is 36.7°C (98.0°F). On physical examination, the patient seems pale and lethargic. On cardiac exam, a pulmonary valve flow murmur is heard. There is significant hepatosplenomegaly present, and several oral mucosal petechiae in the oral cavity are noted. Gum hypertrophy is also present. A peripheral blood smear reveals myeloperoxidase-positive cells and Auer Rods. A bone marrow biopsy shows > 30% of blast cells. Which of the following chromosomal abnormalities is associated with this patient’s most likely diagnosis?", "answer": "t(15;17)", "options": {"A": "JAK2 mutation", "B": "t(9;22)", "C": "t(15;17)", "D": "t(11;14)", "E": "t(8;14)"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An otherwise healthy 16-year-old girl comes to the physician because she has not had a menstrual period. Examination shows normal breast development. There is coarse pubic and axillary hair. Pelvic examination shows a blind vaginal pouch. Ultrasonography shows normal ovaries and an atretic uterus. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Agenesis of the paramesonephric duct", "options": {"A": "Deficiency of 5-alpha reductase", "B": "End-organ insensitivity to androgens", "C": "Monosomy of sex chromosomes", "D": "Agenesis of the paramesonephric duct", "E": "Deficiency of 17-alpha-hydroxylase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 75-year-old woman is being treated for atrial fibrillation. She presents to the clinic with complaints of nausea, vomiting, photophobia, and yellow-green vision with yellow halos around the lights. She has a heart rate of 64/min, blood pressure is 118/76 mm Hg, and respiratory rate is 15/min. Physical examination reveals regular heart sounds with clear lung sounds bilaterally. Liver function tests are normal. Toxicity of which of the following anti-arrhythmic drugs would best fit this clinical picture?", "answer": "Digoxin", "options": {"A": "Digoxin", "B": "Amiodarone", "C": "Propafenone", "D": "Sotalol", "E": "Atenolol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 40-year-old man is rushed to the emergency department after being involved in a motor vehicle accident. He has lacerations on his right arm and some minor abrasions on his face and lower limbs. The resident on call quickly manages the patient with proper care of his open wounds in the emergency department. The patient is admitted to the surgery unit for the daily care of his wounds. His lacerations begin to heal with proper dressing and occasional debridement. Which of the following best describes the healing process in this patient?", "answer": "Healing by secondary intention will occur along with the deposition of large amount of granulation tissue.", "options": {"A": "Abundant lymphocytes accumulate during the healing process, forming a granuloma.", "B": "The formation of granulation tissue is not affected by factors such as blood sugar and decreased circulation of blood.", "C": "Healing by secondary intention will occur along with the deposition of large amount of granulation tissue.", "D": "Healing involves abscess formation, which should be drained.", "E": "Healing by primary intention will occur without granulation tissue formation."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Hormone balance is essential for maintaining a normal pregnancy. Early on, elevated progesterone levels are needed to maintain pregnancy and progesterone is produced in excess by the corpus luteum. In the normal menstrual cycle the corpus luteum involutes, but this process is impeded during pregnancy because of the presence of which hormone?", "answer": "Human chorionic gonadotropin", "options": {"A": "Cortisol", "B": "Human chorionic gonadotropin", "C": "Estrogen", "D": "Progesterone", "E": "Inhibin A"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old man comes to the emergency department because of worsening shortness of breath and a productive cough for 3 days. He sustained trauma to the right hemithorax during a fight 3 weeks ago. He had significant pain and mild shortness of breath following the incident but did not seek medical care. He does not smoke or drink alcohol. He is a construction worker. His temperature is 38.4°C (101.1°F), pulse is 95/min, respirations are 18/min, and blood pressure is 120/75 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Pulmonary examination shows decreased breath sounds over the right lower lung fields. CT scan of the chest shows fractures of the right 7th and 8th ribs, right pleural splitting and thickening, and a dense fluid collection in the pleural space. Which of the following is the most likely diagnosis?", "answer": "Pleural empyema", "options": {"A": "Viral pleurisy", "B": "Lung abscess", "C": "Chylothorax", "D": "Pleural empyema", "E": "Mesothelioma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A cross-sectional oral health survey was designed to assess both functional and psychosocial effects of dental disease on the elderly population of Buda, Texas (US). Printed surveys that consisted of 50 open-ended questions on dental disease history and dental hygiene were mailed to the selected members of a target population. However, the response rate was not satisfactory, as a large percentage of the selected study participants either did not return the survey or failed to answer all of the questions posed. The researchers opted for 2 strategies: prompt those who did not respond with a second letter that guaranteed complete confidentiality and broaden the pool of selected participants. Depending on the final response rate and the researchers’ statistical skills, the bias in the final publication will be more pronounced if...?", "answer": "...the difference between the observed and nonrespondent answers is increased.", "options": {"A": "....the proportion of nonrespondents from the targeted sample is decreased.", "B": "...the specific weighting-class adjustments are used on the final data.", "C": "...the difference between the observed and nonrespondent answers is increased.", "D": "...the auxiliary population variables are introduced by means of a calibration method.", "E": "...the imputation techniques for data correction are employed."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 16-year-old boy is brought to the physician for a follow-up examination. He has a 6-year history of type 1 diabetes mellitus and his only medication is insulin. Seven months ago, he was treated for an episode of diabetic ketoacidosis. He has previously been compliant with his diet and insulin regimen. He wants to join the high school soccer team. Vital signs are within normal limits. His hemoglobin A1C is 6.3%. Which of the following is the most appropriate recommendation at this time?", "answer": "Lower insulin dosage on days of exercise", "options": {"A": "Advise against physical activity", "B": "Lower insulin dosage on days of exercise", "C": "Switch from insulin to metformin", "D": "Increase insulin dosage on days of exercise", "E": "Limit activity to 20 minutes per day"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old woman comes to the physician because of headaches for 1 month. She describes them as 7 out of 10 in intensity. She has no nausea. Two years ago, she was treated for invasive lobular carcinoma of the left breast. She underwent a left mastectomy and multiple cycles of chemotherapy. She has been in good health since this treatment. Her temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 118/72 mm Hg. There is a well-healed scar on the left side of the chest. There is no lymphadenopathy. The abdomen is soft and nontender; there is no organomegaly. Neurologic examination shows no focal findings. An MRI of the brain shows a 4-cm temporal hyperintense mass near the surface of the brain. Which of the following is the most appropriate next step in management?", "answer": "Surgical resection", "options": {"A": "Whole brain radiation therapy", "B": "Surgical resection", "C": "Chemotherapy", "D": "Antibiotic therapy", "E": "Palliative care"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 44-year-old man presents to his primary care physician due to a shock-like pain in his left leg. He describes the pain as sharp and lasting a few minutes at a time. He has noticed being \"clumsy\" when walking in a dark room. Approximately 2 weeks ago, he was helping his daughter move and this required him to lift heavy boxes. He denies any trauma to the back or lower back pain. Medical history is significant for hypertension, hyperlipidemia, and type 2 diabetes mellitus. He is currently sexually active and is in a monogamous relationship with his wife. Approximately 15 years ago, he noted a painless genital lesion. On physical exam, there is a miotic pupil that does not constrict with light but constricts with convergence and accommodation. Strength, reflex, and sensory exam of the lower extremity is unremarkable. The patient has a positive Romberg test. Which of the following is most likely the cause of this patient's symptoms?", "answer": "Sexually transmitted infection", "options": {"A": "Acute ischemic cerebellar stroke", "B": "Diabetic peripheral neuropathy", "C": "Lumbar disc herniation", "D": "Lumbar spinal stenosis", "E": "Sexually transmitted infection"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "The VALIANT trial compared the effect of captopril and valsartan on mortality in patients with myocardial infarction complicated by heart failure. Subjects were randomly assigned to treatment with either captopril or valsartan and subsequently followed for 2 years. The primary endpoint was death from any cause. The study concluded that valsartan was as effective as captopril in patients who are at high risk for cardiac events after an MI. Which of the following describes this type of study?", "answer": "Randomized controlled trial", "options": {"A": "Randomized controlled trial", "B": "Cohort study", "C": "Cross-sectional study", "D": "Case-control study", "E": "Crossover study"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the physician because of a 3-month history of mild right upper abdominal pain. She has not had any fevers, chills, or weight loss. There is no personal or family history of serious illness. Medications include transdermal estrogen, which she recently started taking for symptoms related to menopause. Abdominal examination shows no abnormalities. Ultrasonography of the liver shows a well-demarcated, homogeneous, hyperechoic mass surrounded by normal liver tissue. A biopsy of the lesion would put this patient at greatest risk for which of the following complications?", "answer": "Intraperitoneal hemorrhage", "options": {"A": "Intraperitoneal hemorrhage", "B": "Biliary peritonitis", "C": "Bacteremia", "D": "Metastatic spread", "E": "Anaphylactic shock"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old Honduran woman presents to your clinic with shortness of breath. She reports that her symptoms have progressed over the past several months and are now impacting her quality of life because she cannot complete her usual exercise routine. She recalls \"normal\" childhood illnesses, including sore throats and fevers, but never required hospitalization. Vital signs are temperature 37 degrees Celsius, blood pressure 110/70 mm Hg, heart rate 109/min, respiratory rate 22/min, and oxygen saturation 98% on room air. Physical exam reveals a holosystolic, high-pitched, blowing murmur at the cardiac apex. One would expect that this murmur would also:", "answer": "Increase with squatting or handgrip", "options": {"A": "Radiate to the neck", "B": "Increase with squatting or handgrip", "C": "Increase with inspiration", "D": "Also have a mid-systolic click loudest at S2", "E": "Have a characteristic machine-like sound"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 73-year-old man dies 4 months after being diagnosed with advanced adenocarcinoma of the colon. Examination of the heart at autopsy shows vegetations lining the mitral valve margins. The vegetations are loosely attached and can be easily scraped off. Microscopic examination shows the vegetations to be composed of interwoven fibrin strands with mononuclear cells. The mitral valve endothelium is intact. Which of the following is the most likely underlying cause of these autopsy findings?", "answer": "Procoagulant release", "options": {"A": "Procoagulant release", "B": "Dystrophic calcifications", "C": "Antibody cross-reactivity", "D": "Bacterial colonization", "E": "Metastatic infiltration"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 22-year-old primigravid woman comes to the physician for her first prenatal visit at 10 weeks' gestation. She has no history of serious illness. She has been using cocaine for the past two years. Without cessation of cocaine use, which of the following complications is most likely to occur?", "answer": "Premature delivery", "options": {"A": "Premature delivery", "B": "Obstructed labor", "C": "Congenital heart defect", "D": "Neural tube defects", "E": "Polyhydramnios"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 18-year-old man comes to the physician because of severe left shoulder pain after a basketball match. During the game, the patient sustained an injury to the posterior part of his outstretched arm after being blocked by a defender. Examination shows no gross deformity of the left shoulder. Palpation of the shoulder elicits mild tenderness. Internal rotation of the arm against resistance shows weakness. These findings are most specific for injury to which of the following muscles?", "answer": "Subscapularis", "options": {"A": "Supraspinatus", "B": "Deltoid", "C": "Subscapularis", "D": "Infraspinatus", "E": "Teres minor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A six-month-old male presents to the pediatrician for a well-child visit. His mother reports that the patient has just started eating solids and sleeps well throughout the night. She notes that she often puts the patient to sleep on his stomach because he seems to breathe more easily in that position. The patient’s mother has noticed that the patient’s breathing becomes more “strained” when lying on his back. She cannot remember when this problem began, but she believes it has gotten worse in recent weeks. The patient was born at 40 weeks gestation and has no other past medical history. The patient’s temperature is 98.0°F (36.7°C), blood pressure is 75/55 mmHg, pulse is 115/min, and respirations are 24/min. His oxygen saturation is 98% on room air. On physical exam, the patient appears comfortable and has inspiratory stridor that improves while leaning forward. His lungs are otherwise clear to auscultation bilaterally. Which of the following is the most likely cause of this patient’s respiratory symptoms?", "answer": "Laryngomalacia", "options": {"A": "Epiglottitis", "B": "Foreign body aspiration", "C": "Laryngomalacia", "D": "Laryngotracheitis", "E": "Vascular ring"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 36-year-old woman comes to the physician because of blurred vision and difficulty keeping her eyes open. She also has occasional difficulty chewing, especially when eating meat or other foods that require prolonged chewing. The symptoms are worse at the end of the day. Physical examination shows bilateral drooping of the eyelids, which becomes more pronounced when she is asked to look upwards for 30 seconds. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Decreased generation of end plate potential", "options": {"A": "Inhibition of calcium release from the sarcoplasmic reticulum", "B": "Interrupted transmission of T-tubule depolarization", "C": "Sustained blockade of actin myosin-binding sites", "D": "Decreased generation of end plate potential", "E": "Impaired flow of calcium ions between gap junctions"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man presents to the emergency room for a generalized tonic-clonic seizure. After stabilizing the patient, a full radiologic evaluation reveals multiple contrast-enhancing lesions in the brain, lungs, and liver. According to his wife, he lost several pounds in the last few months. The medical history is relevant for cryptorchidism, with abdominal testes that were surgically transferred to the scrotum just before he turned 1-year old. His lab investigation reveals:\nα-fetoprotein: \n9 ng/mL (normal values < 10 ng/mL)\nHuman chorionic gonadotropin: \n1,895 IU/L (normal values < 0.5 IU/L)\nWhich of the following microscopic features best describes the lesions seen in this patient's imaging study?", "answer": "Intimate association of syncytiotrophoblast and cytotrophoblast cells", "options": {"A": "Glomerulus-like structure with a mesoderm core, a central capillary, and lined with germ cells", "B": "Germ cells with well-defined borders, central nuclei, prominent nucleoli, and clear cytoplasm", "C": "Cells with hyaline-like globules", "D": "Mixture of primitive neuroectoderm, loose mesenchyme, and primitive glandular structures", "E": "Intimate association of syncytiotrophoblast and cytotrophoblast cells"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old woman with type 2 diabetes mellitus comes to the physician because of a 1-year history of progressively worsening paresthesias in her upper limbs. She has accidentally burned her fingers on hot dishes several times. She was involved in a motor vehicle collision 3 years ago. Neurologic examination shows absent temperature sensation with normal fine touch sensation over the upper extremities and chest. Without treatment, this patient is at increased risk of developing which of the following?", "answer": "Drooping of the eyelid", "options": {"A": "Exaggerated biceps reflex", "B": "Decreased Mini-Mental State Examination score", "C": "Absent anal wink reflex", "D": "Drooping of the eyelid", "E": "Absent knee-jerk reflex"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old woman, gravida 2, para 1, at 38 weeks' gestation is admitted to the hospital 30 minutes after spontaneous rupture of membranes. Her pregnancy has been complicated by gestational diabetes treated with insulin. Her first child was delivered vaginally. Her immunizations are up-to-date. She delivers the child via cesarean section without complications after failure to progress for 16 hours. Fourteen hours after birth, she reports having body aches and feeling warm. She has to change her perineal pad every 2–3 hours. She has abdominal cramping, especially when breastfeeding. She has voided her bladder four times since the birth. She appears uncomfortable. Her temperature is 37.9°C (100.2°F), pulse is 85/min, respirations are 18/min, and blood pressure is 115/60 mm Hg. The abdomen is soft, distended, and nontender. There is a healing transverse suprapubic incision without erythema or discharge. A firm, nontender uterine fundus is palpated at the level of the umbilicus. There is bright red blood on the perineal pad. The breasts are engorged and tender, without redness or palpable masses. Which of the following is the most appropriate next step in management?", "answer": "Observation\n\"", "options": {"A": "Dilation and curettage", "B": "Pelvic ultrasound", "C": "Hysterectomy", "D": "Administration of intravenous clindamycin and gentamycin", "E": "Observation\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old chronic smoker presents to the physician with a complaint of worsening left shoulder pain for several months which has become acutely worse the past 2 weeks and now radiates down his left arm. Physical examination reveals a palpable 2 x 1.5 cm supraclavicular lymph node along with decreased grip strength in his left hand. Examination of the face reveals partial ptosis of the left eyelid and miosis of the left eye. Laboratory testing shows the following values:\nSodium (Na+) 135 mEq/L\nPotassium (K+) 3.6 mEq/L\nChloride (Cl-) 100 mEq/L\nBUN 12 mg/dL\nCreatinine (Cr) 0.6 mg/dL\nMagnesium (Mg2+) 1.5 mg/dL\nPhosphate 3 mg/dL\nCalcium (Ca2+) 8.5 mg/dL\nAn X-ray of the chest reveals a soft tissue mass at the apex of the left lung with possible involvement of the first rib. What is the most likely diagnosis?", "answer": "Pancoast tumor", "options": {"A": "Pulmonary hamartoma", "B": "Mesothelioma", "C": "Pancoast tumor", "D": "Subclavian aneurysm", "E": "Osteophyte"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old 70 kilogram African-American man with epilepsy refractory to valproic acid, phenytoin, and levetiracetam undergoes magnetic resonance imaging of his brain under monitored anesthetic care. He wakes up screaming in pain due to an electrocardiogram lead having caused a significant thermal burn circumferentially around his left leg. He is admitted to the medical intensive care unit for continuous electroencephalogram monitoring while on a midazolam infusion for seizure suppression and supportive care for his burn. Overnight, the nurse continues to increase the patient's midazolam infusion rate, but she also notices that his left toes are cold to touch with significant edema. His temperature is 100°F (37.8°C), blood pressure is 110/75 mmHg, pulse is 80/min, respirations are 10/min and oxygen saturation is 95% on 2 liters nasal cannula. No dorsalis pedis or posterior tibial pulses are detected on the left lower extremity. A delta pressure of 25 mmHg is obtained in the left leg. What is the best next step in management?", "answer": "Escharotomy", "options": {"A": "Amputation", "B": "Escharotomy", "C": "Fasciotomy", "D": "Intravenous fluid infusion based on Parkland formula", "E": "Transfer to burn center"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 60-year-old African American woman presents to her ophthalmologist with blurry vision. She reports a 2-month history of decreased vision primarily affecting her right eye. Her past medical history is notable for type 1 diabetes and hypertension. She takes insulin and enalapril. She has a 40-pack-year smoking history and drinks a glass of wine at dinner each night. Her family history is notable for glaucoma in her mother and severe diabetes complicated by nephropathy and retinopathy in her father. Her temperature is 99°F (37.2°C), blood pressure is 134/82 mmHg, pulse is 88/min, and respirations are 18/min. On exam, she is well-appearing and in no acute distress. The physician asks the patient to look forward and shines a penlight first in one eye, then the other, alternating quickly to observe the pupillary response to the light. When the light is shined in the right eye, both pupils partially constrict. When the light is shined in the left eye, both pupils constrict further. When the light is moved back to the right eye, both eyes dilate slightly to a partially constricted state. Where is the most likely site of this patient’s lesion?", "answer": "Optic nerve", "options": {"A": "Ciliary ganglion", "B": "Lateral geniculate nucleus", "C": "Lens", "D": "Oculomotor nerve", "E": "Optic nerve"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old man with a history of diabetes mellitus presents for a primary care visit. His diabetes is well controlled on metformin, with fasting glucose concentrations between 110–150 mg/dl. His blood pressure on multiple office visits are between 115-130/75-85 mmHg. Today his temperature is 98°F (36.7 °C), blood pressure is 125/80 mmHg, pulse is 86/min, and respirations are 15/min. Labs are obtained with the following results:\n\nHemoglobin A1c: 6.7%\nGlucose: 120 mg/dl\nCholesterol (plasma): 190 mg/dL\nUrine albumin: 60mg/24hr\n\nWhich of the following treatments is effective in slowing the progression of the most likely cause of this patient's abnormal albumin result?", "answer": "Enalapril", "options": {"A": "No effective treatments", "B": "Enalapril", "C": "Metformin", "D": "Simvastatin", "E": "Aspirin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old woman with a missed menstrual cycle has a positive pregnancy test. The estimated gestational age is 4 weeks. The patient questions the pregnancy test results and mentions that a urinary pregnancy test she took 3 weeks ago was negative. What is the explanation for the patient’s first negative pregnancy test result?", "answer": "The syncytiotrophoblast had not yet developed to produce human chorionic gonadotropin at that term.", "options": {"A": "The embryonic liver has not yet developed to produce human chorionic gonadotropin at that term.", "B": "The syncytiotrophoblast had not yet developed to produce human chorionic gonadotropin at that term.", "C": "Pregnancy test becomes positive during organogenesis so should be expected positive no earlier than at week 4.", "D": "Human chorionic gonadotropin starts to be produced by the uterus only after the embryonic implantation which has not yet occurred.", "E": "Human chorionic gonadotropin can only be found in the urine after its placental production is started."}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old man is brought to the emergency department by ambulance after he fainted in the supermarket. He recently had 2 days of gastroenteritis, but did not come to the hospital for treatment. He also recently arrived in Denver for a vacation, but normally lives in Florida. His past medical history is significant for morbid obesity and heavy alcohol use. Arterial blood gas and serum chemistry results are shown below:\n\nSodium: 138 mEq/L\nChloride: 121 mEq/L\nBicarbonate: 8 mEq/L\npH: 7.25\nPaCO2: 20 mmHg\n\nWhich of the following etiologies is most likely responsible for this patient's findings?", "answer": "Diarrhea", "options": {"A": "Altitude sickness", "B": "Diarrhea", "C": "Ethanol consumption", "D": "Hypoventilation", "E": "Vomiting"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old boy is brought to the emergency department by his mother because of a 5-hour history of right lower quadrant pain, vomiting, and abdominal distention. Examination shows a palpable mass in the right lower quadrant of the abdomen. An x-ray of the abdomen shows a dilated ascending colon with an air-fluid level in the small intestine. A test is performed in which electrodes are placed on the nasal epithelium and the nose is perfused with several different solutions. When a chloride-free solution is administered, hyperpolarization across the nasal epithelium is absent. Which of the following is the most common cause of mortality in patients with the condition described here?", "answer": "Pulmonary infection", "options": {"A": "Liver cirrhosis", "B": "Pulmonary embolism", "C": "Diabetes mellitus", "D": "Pulmonary infection", "E": "Nephrolithiasis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 8-year-old boy is brought by his mother to his pediatrician because his urine is tea-colored and his face has appeared puffy for the past 2 days. He suffered a fever and sore throat several weeks ago that was treated with ibuprofen. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Today, his heart rate is 100/min, the respiratory rate is 22/min, the blood pressure is 130/80 mm Hg, and the temperature is 36.8°C (98.2°F). On physical exam the boy has mild periorbital swelling. A urine dipstick reveals 1+ proteinuria and urinalysis reveals 10–15 red cells/high power field and dysmorphic red cells. The pediatrician is concerned with the child’s hypertension, facial edema, and abnormal urine analysis results. Which of the following best represents the mechanism of this patient’s condition?", "answer": "Immune complex deposition", "options": {"A": "Diffuse mesangial IgA deposition", "B": "Immune complex deposition", "C": "Complement-dependent antibody reaction", "D": "Complement-independent reaction", "E": "Podocyte injury"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 39-year-old man presents to his primary care physician with new onset lower extremity edema, fatigue, and hematuria. His symptoms began approximately 2 weeks prior to presentation and have progressively worsened. Medical history is significant for opioid-use disorder with heroin treated with methadone. He is in a monogamous relationship with a female partner of 4 years and does not use condoms. He denies cigarette smoking, alcohol use, and last used heroin approximately 1 month ago. His temperature is 99°F (37.2°C), blood pressure is 152/98 mmHg, pulse is 83/min, and respirations are 17/min. On physical exam, there is conjunctival pallor, scleral icterus, a 14 cm liver span, acrocyanosis, and lower extremity 2+ pitting edema. Urinalysis demonstrates proteinuria and dysmorphic red blood cells. Laboratory testing reveals a mildly decreased C3 and decreased C4 serum concentration. Which of the following will most likely be present on renal biopsy in this patient?", "answer": "Diffuse mesangial cell proliferation with capillary wall thickening", "options": {"A": "Apple-green birefringence on Congo red stain", "B": "Diffuse mesangial cell proliferation with capillary wall thickening", "C": "Enlarged and hypercellular glomeruli", "D": "Glomerular basement membrane thinning and splitting", "E": "Normal appearing glomerulus"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 16-year-old boy presents after suffering a tonic-clonic seizure. He says it had a duration of 2 minutes and a postictal period of 10 minutes. Patient denies any similar episodes in the past. Past medical history is unremarkable. Family history is significant for his mother and older brother who died of colorectal cancer at ages 40 and 20, respectively. On physical examination, the patient is drowsy but arousable and responsive to commands. Both pupils are symmetrical and responsive to light. An MRI of the brain reveals an infratentorial hypointense cerebellar mass with a small cystic area. Which of the following is the most likely diagnosis in this patient?", "answer": "Turcot syndrome", "options": {"A": "Peutz-Jeghers syndrome", "B": "Lynch syndrome", "C": "Gardner syndrome", "D": "Turcot syndrome", "E": "Cowden syndrome"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2-day-old boy fails to pass meconium for the first 48 hours of life. He was born at term to a healthy 19-year-old woman after an uncomplicated pregnancy. At birth, his weight was 3.9 kg (8.6 lb); at the time of presentation, he weighs 3.8 kg (8.4 lb). His vital signs are as follows: blood pressure 70/50 mm Hg, heart rate 130/min, respiratory rate 33/min, and temperature 37.0℃ (98.6℉). On physical examination, he is fussy and appears mildly dehydrated. Bowel sounds are active on auscultation. His abdomen is mildly distended and no masses can be identified on palpation. The patient’s anus is patent. An upper gastrointestinal study with oral contrast demonstrates normal anatomy. A lower gastrointestinal series with barium enema reveals a large amount of retained barium contrast within a dilated sigmoid colon and a normal appearing rectum. The barium solution retention persisted beyond 24 hours after administration. Which of the following best describes the cause of the patient’s symptoms?", "answer": "Failure of neural crest cells to migrate caudally to intestinal wall during embryogenesis", "options": {"A": "Failure of neural crest cells to migrate caudally to intestinal wall during embryogenesis", "B": "Disruption of apoptosis of intestinal cells", "C": "Hypertrophy of the muscular layer of the lower sigmoid colon", "D": "Propelling of a polyp distally by peristalsis", "E": "Decreased blood supply to developing intestine in the embryonic period"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old woman with a past medical history of obesity and longstanding GERD presents to the emergency room with chest pain. She describes the pain as central with a sensation of something being stuck in her chest, and this is the third episode in the last month. The prior two incidents occurred at the gym while she was drinking a sport drink and resolved after resting for 3-4 minutes. This episode started after she received news that her father had just had a heart attack at age 69 and has lasted for 15 minutes. The patient also notes several months of intermittent difficulty swallowing but denies palpitations, diaphoresis, or shortness of breath. The patient has a family history of scleroderma in her mother. In the emergency room, her temperature is 98.4°F (36.8°C), blood pressure is 143/82 mmHg, pulse is 89/min, and respirations are 16/min. The patient appears mildly uncomfortable but exam is otherwise unremarkable. Which of the following is the most appropriate confirmatory test for this patient’s condition?", "answer": "Esophageal manometry", "options": {"A": "Endoscopy", "B": "Esophageal manometry", "C": "Barium swallow", "D": "EKG", "E": "Troponin I"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old man comes to the physician because of several episodes of crushing substernal chest pain on exertion over the past 6 weeks. The pain occurs when he goes for his morning run and disappears if he slows down to a walk. The patient is concerned because two of his uncles died of myocardial infarction in their early 50s. Physical examination shows yellow plaques on both the palms. An ECG shows no abnormalities. Serum lipid studies show:\nTotal cholesterol 650 mg/dL\nHDL cholesterol 30 mg/dL\nVLDL cholesterol 185 mg/dL\nTriglycerides 800 mg/dL\nChylomicron remnants elevated\nWhich of the following is the most likely cause of this patient's symptoms?\"", "answer": "Defective apolipoprotein E\n\"", "options": {"A": "Hepatic overproduction of VLDL", "B": "Defective apolipoprotein B-100", "C": "Decreased apolipoprotein B-48", "D": "Decreased apolipoprotein C-II", "E": "Defective apolipoprotein E\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old woman comes to the physician because of a 2-month history of vaginal bleeding after intercourse. Menarche occurred at the age of 13 years and menses occur at regular 28-day intervals. Gynecologic examination shows an irregular lesion at the cervical os. Histological evaluation of a cervical biopsy specimen obtained on colposcopy confirms a diagnosis of in-situ cervical cancer. This cancer is most likely derived from which of the following types of cells?", "answer": "Non-keratinized stratified squamous epithelium", "options": {"A": "Simple columnar epithelium with tubular glands", "B": "Ciliated simple columnar epithelium", "C": "Non-keratinized stratified squamous epithelium", "D": "Simple cuboidal epithelium", "E": "Keratinized stratified squamous epithelium"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old college professor with a long-standing history of neuropathic pain presents to a medical clinic with weight loss and early morning awakening for the past several months. She feels as if she has no energy to go about her work. She complains that she is not as focused at work or home as she used to be and finds both her life and work unfulfilling. She has had these symptoms for the past 2 months. She was started on antidepressants in the past, but the antidepressants did not provide any significant improvement. She eventually improved and has been in remission for almost 1 year now. She would really like a simple treatment option to address both her neuropathic pain and her depression, and she is started on a tricyclic antidepressant. What safety advice is most important for this patient’s treatment plan?", "answer": "The medication can cause serotonin syndrome.", "options": {"A": "The medication can cause serotonin syndrome.", "B": "The medication can cause agranulocytosis.", "C": "The medication can lower the seizure threshold.", "D": "The medication has a very short half-life.", "E": "This medication is rarely lethal at high doses."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 8-month-old girl is brought to the emergency department because of fever, vomiting, and diarrhea for 3 days. Her parents report at least 10 watery stools daily. She has had three upper respiratory tract infections since she started daycare 2 months ago, but has otherwise been developing normally. Her mother has a history of celiac disease. The patient is at the 57th percentile for height and the 65th percentile for weight. Her immunizations are incomplete. Her temperature is 38.5°C (101.3°F), pulse is 145/min, and blood pressure is 92/54 mm Hg. Examination shows dry mucous membranes and decreased skin turgor. Bowel sounds are hyperactive. A complete blood count and serum concentrations of glucose, urea nitrogen, and creatinine are within the reference range; there is hypokalemia. In addition to intravenous fluid resuscitation, which of the following is the most appropriate next step in management?", "answer": "Enzyme immunoassay of stool", "options": {"A": "Sonography of the abdomen", "B": "Administration of antidiarrheal medication", "C": "Blood cultures", "D": "Examination of the stool for ova and parasites", "E": "Enzyme immunoassay of stool"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 5-year-old girl is brought to her pediatrician for vaccinations and a physical. She is a generally healthy child with no thumb on her right hand and a shortened and deformed left thumb. She was born at 39 weeks gestation via spontaneous vaginal delivery and is up to date on all vaccines and meeting all developmental milestones. On physical examination her vital signs are stable. On auscultation of the heart, the pediatrician notes a wide fixed split in the second heart sound (S2) and a medium-pitched systolic ejection murmur at the left sternal border. The murmur is not harsh in quality and is not accompanied by a thrill. Her echocardiogram confirms the diagnosis of acyanotic congenital heart defect with left-to-right shunt. Which of the following genetic syndromes is most consistent d with this girl’s congenital defects?", "answer": "Holt-Oram syndrome", "options": {"A": "Alagille syndrome", "B": "DiGeorge syndrome", "C": "Holt-Oram syndrome", "D": "Marfan syndrome", "E": "Williams-Beuren syndrome"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman presents to the emergency department with pain and frequent urination. She states she has felt uncomfortable with frequent small-volume urinary voids for the past 3 days, which have progressively worsened. The patient has no past medical history. She currently smokes 1 pack of cigarettes per day and engages in unprotected sex with 2 male partners. Her temperature is 103°F (39.4°C), blood pressure is 127/68 mmHg, pulse is 97/min, respirations are 17/min, and oxygen saturation is 98% on room air. Cardiac, pulmonary, and abdominal exams are within normal limits. There is tenderness upon palpation of the left costovertebral angle and the left flank. Urine is collected and a pregnancy test is negative. Which of the following is the best next step in management?", "answer": "Levofloxacin and outpatient followup", "options": {"A": "Abscess drainage and IV antibiotics", "B": "Analgesics, encourage oral fluid intake, and discharge", "C": "Ceftriaxone and hospital admission", "D": "Levofloxacin and outpatient followup", "E": "Nitrofurantoin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old woman presents to the occupational health clinic for a new employee health screening. She has limited medical records prior to her immigration to the United States several years ago. She denies any current illness or significant medical history. Purified protein derivative (PPD) is injected on the inside of her left forearm for tuberculosis (TB) screening. Approximately 36 hours later, the patient comes back to the occupational health clinic and has an indurated lesion with bordering erythema measuring 15 mm in diameter at the site of PPD injection. Of the following options, which is the mechanism of her reaction?", "answer": "Type IV–cell-mediated (delayed) hypersensitivity reaction", "options": {"A": "Type I–anaphylactic hypersensitivity reaction", "B": "Type II–cytotoxic hypersensitivity reaction", "C": "Type III–immune complex-mediated hypersensitivity reaction", "D": "Type IV–cell-mediated (delayed) hypersensitivity reaction", "E": "Type III and IV–mixed immune complex and cell-mediated hypersensitivity reactions"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old HIV positive female known to be non-adherent to her treatment regimen, presents to the hospital with the complaint of new-onset headaches. Her vital signs are only significant for a low-grade fever. Neurological examination reveals right-sided upper motor neuron signs, as well as a inattention and difficulty with concentration. The patient currently does not have a primary medical provider. A CT of the patients head is shown in the image below. What is the next best step in management for this patient?", "answer": "Begin treatment with pyrimethamine-sulfadiazine", "options": {"A": "Perform a biopsy of the lesion", "B": "Perform an analysis for 14-3-3 protein levels", "C": "Begin treatment with pyrimethamine-sulfadiazine", "D": "Begin treatment with albendazole and corticosteroids", "E": "Begin treatment with acyclovir"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 29-year-old woman, gravida 1, para 1, comes to the physician because of difficulty conceiving for one year. She is sexually active with her husband 4–5 times a week. Pregnancy and delivery of her first child 3 years ago were uncomplicated. She returned to work as an event coordinator 12 months ago and has found the transition stressful. Menses previously occurred at 30-day intervals and lasted for 3–4 days with moderate flow. Her last menstrual period was three months ago. She has occasional vaginal dryness. The patient runs 5 to 10 miles every day. Her BMI is 19.0 kg/m2. Her pulse is 73/min and blood pressure is 125/70 mm Hg. Abdominal examination shows no abnormalities. Pelvic examination shows dry vaginal mucosa. A serum pregnancy test is negative. Serum studies show:\nProlactin 18 μg/L\nThyroid-stimulating hormone 2.5 mU/L\nFollicle-stimulating hormone 3.6 U/L\nLuteinizing hormone 2.3 U/L\nUltrasound of the pelvis shows no abnormalities. In addition to dietary and exercise counseling, which of the following is the most appropriate next step in management?\"", "answer": "Offer pulsatile gonadotropin-releasing hormone therapy", "options": {"A": "Offer clomiphene citrate therapy", "B": "Offer in vitro fertilization", "C": "Offer pulsatile gonadotropin-releasing hormone therapy", "D": "Offer human chorionic gonadotropin therapy", "E": "Obtain MRI of the pituitary gland"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A neonate is noted to have very light skin, light blue eyes, and sparse blonde-white hair. The family states that the baby is much lighter in appearance than anyone else in the family. Both parents are Fitzpatrick skin type III with dark brown hair. On further exam, the baby's temperature is 98.4°F (36.9°C), blood pressure is 110/70 mmHg, pulse is 88/min, and respirations are 14/min. The patient is oxygenating well at SpO2 of 97% on room air with no respiratory distress. All reflexes are appropriate, and the APGAR score is 10. A referral is placed with Ophthalmology for a comprehensive eye exam. The condition is believed to be due to an enzyme deficiency, and a hair bulb assay is performed. Which of the following substrates should be incubated with the specimen in order to determine the activity of the enzyme in question for this disease?", "answer": "Dihydroxyphenylalanine", "options": {"A": "Dihydroxyphenylalanine", "B": "Dopamine", "C": "Homogentisic Acid", "D": "Pyridoxine", "E": "Tetrahydrobiopterin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-year-old girl is brought to the emergency room by her parents for seizure-like activity earlier today. Her mother describes that she was napping when both of her arms began to twitch and she started foaming at the mouth. She was unresponsive during this time and the episode lasted a total of 30 seconds. The mother denies any fever, pain, recent trauma, changes in feeding, or gastrointestinal changes in her daughter. She states her daughter has recently been lethargic and is currently receiving antibiotics for an ear infection. The patient was born vaginally at home via a midwife without any complications. A physical examination is unremarkable. Results of her laboratory studies are shown below.\n\nHemoglobin: 13 g/dL\nHematocrit: 38%\nLeukocyte count: 7,600/mm^3 with normal differential\nPlatelet count: 170,000/mm^3\n\nSerum:\nNa+: 136 mEq/L\nCl-: 101 mEq/L\nK+: 3.9 mEq/L\nHCO3-: 20 mEq/L\nBUN: 25 mg/dL\nGlucose: 34 mmol/L\nCreatinine: 0.8 mg/dL\nThyroid-stimulating hormone: 3.2 µU/mL\nCa2+: 9.3 mg/dL\nAST: 183 U/L\nALT: 220 U/L\n\nWhat is the most likely explanation for this patient’s symptoms?", "answer": "Medium-chain acyl-CoA dehydrogenase deficiency", "options": {"A": "Accumulation of sphingomyelin", "B": "Defieincy of myophosphorylase", "C": "Infection with Streptococcus pneumoniae", "D": "Medium-chain acyl-CoA dehydrogenase deficiency", "E": "Primary carnitine deficiency"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A first-year medical student is analyzing data in a nationwide cancer registry. She identified a group of patients who had recently undergone surgery for epithelial ovarian cancer and achieved a complete clinical response to chemotherapy. Some of these patients had been scheduled to receive annual abdominal CTs while other patients had not been scheduled for such routine imaging surveillance. The medical student then identified a subgroup of patients who have developed recurrent metastatic disease despite their previous complete clinical response to chemotherapy and surgery. She compared patients who were diagnosed with metastatic cancer during routine follow-up imaging with patients who were diagnosed with metastatic cancer based on clinical symptoms at routine follow-up history and physical exams. She found that the average survival of patients who underwent routine imaging was four months longer than the survival of their peers who were diagnosed based on history and physical exam. Which of the following is a reason why these results should be interpreted with caution?", "answer": "Lead-time bias", "options": {"A": "Observer bias", "B": "Lead-time bias", "C": "Confounding bias", "D": "Length-time bias", "E": "Surveillance bias"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old man is brought to the physician for a follow-up examination. He has a history of epilepsy that has been treated with a stable dose of phenytoin for 15 years. He was recently seen by another physician who added a drug to his medications, but he cannot recall the name. Shortly after, he started noticing occasional double vision. Physical examination shows slight vertical nystagmus and gait ataxia. Which of the following drugs was most likely added to this patient's medication regimen?", "answer": "Cimetidine", "options": {"A": "Modafinil", "B": "Nafcillin", "C": "Cimetidine", "D": "St. John's wort", "E": "Rifampin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old man presents to his psychiatrist for continuing cognitive behavioral therapy for bipolar disorder. At this session, he reveals that he has had fantasies of killing his boss because he feels he is not treated fairly at work. He says that he has been stalking his boss and has made detailed plans for how to kill him in about a week. He then asks his psychiatrist not to reveal this information and says that he shared it only because he knew these therapy sessions would remain confidential. Which of the following actions should the psychiatrist take in this scenario?", "answer": "Contact the police to warn them about this threat against the patient's wishes", "options": {"A": "Ask for the patient's permission to share this information and share only if granted", "B": "Contact the police to warn them about this threat against the patient's wishes", "C": "Refer the patient to the ethics board of the hospital that meets in 1 week", "D": "Respect patient confidentiality and do not write down this information", "E": "Write the information in the note but do not contact the police"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old woman is admitted to the hospital with headache, photophobia, vomiting without nausea, and fever, which have evolved over the last 12 hours. She was diagnosed with systemic lupus erythematosus at 30 years of age and is on immunosuppressive therapy, which includes oral methylprednisolone. She has received vaccinations—meningococcal and pneumococcal vaccination, as well as BCG. Her vital signs are as follows: blood pressure 125/70 mm Hg, heart rate 82/min, respiratory rate 15/min, and temperature 38.7°C (101.7°F). On examination, her GCS score is 15. Pulmonary, cardiac, and abdominal examinations are within normal limits. A neurologic examination does not reveal focal symptoms. Moderate neck stiffness and a positive Brudzinski’s sign are noted. Which of the following would you expect to note in a CSF sample?", "answer": "Listeria monocytogenes growth in the CSF culture", "options": {"A": "Lymphocytic pleocytosis", "B": "Formation of a spiderweb clot in the collected CSF", "C": "Haemophilus influenzae growth is the CSF culture", "D": "Decrease in CSF protein level", "E": "Listeria monocytogenes growth in the CSF culture"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old female presents to the emergency room as a trauma after a motor vehicle accident. The patient was a restrained passenger who collided with a drunk driver traveling approximately 45 mph. Upon impact, the passenger was able to extricate herself from the crushed car and was sitting on the ground at the scene of the accident. Her vitals are all stable. On physical exam, she is alert and oriented, speaking in complete sentences with a GCS of 15. She has a cervical spine collar in place and endorses exquisite cervical spine tenderness on palpation. Aside from her superficial abrasions on her right lower extremity, the rest of her examination including FAST exam is normal. Rapid hemoglobin testing is within normal limits. What is the next best step in management of this trauma patient?", "answer": "CT cervical spine", "options": {"A": "CT cervical spine", "B": "Remove the patient’s cervical collar immediately", "C": "Discharge home and start physical therapy", "D": "Consult neurosurgery immediately", "E": "Initiate rapid sequence intubation."}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 41-year-old man presents to the emergency department with several days of hand tremor, vomiting, and persistent diarrhea. His wife, who accompanies him, notes that he seems very “out of it.” He was in his usual state of health last week and is now having difficulties at work. He has tried several over-the-counter medications without success. His past medical history is significant for bipolar disorder and both type 1 and type 2 diabetes. He takes lithium, metformin, and a multivitamin every day. At the hospital, his heart rate is 90/min, respiratory rate is 17/min, blood pressure is 130/85 mm Hg, and temperature is 37.0°C (98.6°F). The man appears uncomfortable. His cardiac and respiratory exams are normal and his bowel sounds are hyperactive. His lithium level is 1.8 mEq/L (therapeutic range, 0.6–1.2 mEq/L). Which of the following may have contributed to this patient’s elevated lithium level?", "answer": "Decreased salt intake", "options": {"A": "Decreased salt intake", "B": "Weight loss", "C": "Large amounts of caffeine intake", "D": "Addition of fluoxetine to lithium therapy", "E": "Addition of lurasidone to lithium therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man presents for a routine checkup. He says he has arthralgia in his hands and wrists. No significant past medical history. The patient takes no current medications. Family history is significant for his grandfather who died of liver cirrhosis from an unknown disease. He denies any alcohol use or alcoholism in the family. The patient is afebrile and vital signs are within normal limits. On physical examination, there is bronze hyperpigmentation of the skin and significant hepatomegaly is noted. The remainder of the exam is unremarkable. Which of the following is true about this patient’s most likely diagnosis?", "answer": "A triad of cirrhosis, diabetes mellitus, and skin pigmentation is characteristic", "options": {"A": "The associated dilated cardiomyopathy is irreversible", "B": "The arthropathy is due to iron deposition in the joints.", "C": "A hypersensitivity reaction to blood transfusions causes the iron to accumulate", "D": "Increased ferritin activity results in excess iron accumulation", "E": "A triad of cirrhosis, diabetes mellitus, and skin pigmentation is characteristic"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old man comes to the physician because of a 2-month history of upper abdominal pain that occurs immediately after eating. The pain is sharp, localized to the epigastrium, and does not radiate. He reports that he has been eating less frequently to avoid the pain and has had a 4-kg (8.8-lb) weight loss during this time. He has smoked a pack of cigarettes daily for 20 years and drinks 3 beers daily. His vital signs are within normal limits. He is 165 cm (5 ft 5 in) tall and weighs 76.6 kg (169 lb); BMI is 28 kg/m2. Physical examination shows mild upper abdominal tenderness with no guarding or rebound. Bowel sounds are normal. Laboratory studies are within the reference range. This patient is at greatest risk for which of the following conditions?", "answer": "Gastrointestinal hemorrhage", "options": {"A": "Malignant transformation", "B": "Biliary tract infection", "C": "Pyloric scarring", "D": "Gastrointestinal hemorrhage", "E": "Subhepatic abscess formation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 47-year-old female with a history of poorly controlled type I diabetes mellitus and end-stage renal disease undergoes an allogeneic renal transplant. Her immediate post-operative period is unremarkable and she is discharged from the hospital on post-operative day 4. Her past medical history is also notable for major depressive disorder, obesity, and gout. She takes sertraline, allopurinol, and insulin. She does not smoke or drink alcohol. To decrease the risk of transplant rejection, her nephrologist adds a medication known to serve as a precursor to 6-mercaptopurine. Following initiation of this medication, which of the following toxicities should this patient be monitored for?", "answer": "Pancytopenia", "options": {"A": "Hyperlipidemia", "B": "Osteoporosis", "C": "Hirsutism", "D": "Cytokine storm", "E": "Pancytopenia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2-year-old boy is brought to the physician because of coughing and difficulty breathing that started shortly after his mother found him in the living room playing with his older brother's toys. He appears anxious. Respirations are 33/min and pulse oximetry on room air shows an oxygen saturation of 88%. Physical examination shows nasal flaring and intercostal retractions. Auscultation of the lungs shows a high-pitched inspiratory wheeze and absent breath sounds on the right side. There is no improvement in his oxygen saturation after applying a non-rebreather mask with 100% FiO2. Which of the following terms best describes the most likely underlying mechanism of the right lung's impaired ventilation?", "answer": "Right-to-left shunt", "options": {"A": "Alveolar hyperventilation", "B": "Alveolar dead space", "C": "Diffusion limitation", "D": "Alveolar hypoventilation", "E": "Right-to-left shunt"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man undergoing surgical correction of his deviated septum experiences excessive bleeding on the operating room table. Preoperative prothrombin time and platelet count were normal. The patient’s past medical history is significant for frequent blue blemishes on his skin along with easy bruising since he was a child. He indicated that he has some sort of genetic blood disorder running in his family but could not recall any details. Which of the following is the most appropriate treatment for this patient’s most likely condition?", "answer": "Desmopressin and tranexamic acid", "options": {"A": "Desmopressin and tranexamic acid", "B": "Cryoprecipitate", "C": "Fresh frozen plasma", "D": "Recombinant factor IX", "E": "Red blood cell transfusion"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old woman comes to the physician for a routine examination. She has no history of serious medical illness. She appears well. Physical examination shows several hundred pigmented lesions on the back and upper extremities. A photograph of the lesions is shown. The remainder of the examination shows no abnormalities. This patient is at increased risk of developing a tumor with which of the following findings?", "answer": "S100-positive epithelioid cells with fine granules", "options": {"A": "Atypical keratinocytes forming keratin pearls", "B": "S100-positive epithelioid cells with fine granules", "C": "Spindle endothelial cells forming slit-like spaces", "D": "Mucin-filled cells with peripheral nuclei", "E": "Pale, round cells with palisading nuclei"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old man comes to the physician because of progressive shortness of breath, exercise intolerance, and cough for the past 6 months. He is no longer able to climb a full flight of stairs without resting and uses 3 pillows to sleep at night. He has a history of using cocaine in his 30s but has not used any illicit drugs for the past 20 years. His pulse is 99/min, respiratory rate is 21/min, and blood pressure is 95/60 mm Hg. Crackles are heard in both lower lung fields. An x-ray of the chest shows an enlarged cardiac silhouette with bilateral fluffy infiltrates and thickening of the interlobar fissures. Which of the following findings is most likely in this patient?", "answer": "Decreased lung compliance", "options": {"A": "Decreased pulmonary vascular resistance", "B": "Decreased lung compliance", "C": "Decreased forced expiratory volume", "D": "Increased carbon dioxide production", "E": "Increased residual volume\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old teenager presents for a sports physical. His blood pressure is 110/70 mm Hg, temperature is 36.5°C (97.7°F), and heart rate is 100/min. On cardiac auscultation, an early diastolic heart sound is heard over the cardiac apex while the patient is in the left lateral decubitus position. A transthoracic echocardiogram is performed which shows an ejection fraction of 60% without any other abnormalities. Which of the following is the end-systolic volume in this patient if his cardiac output is 6 L/min?", "answer": "40 mL", "options": {"A": "50 mL", "B": "60 mL", "C": "100 mL", "D": "40 mL", "E": "120 mL"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 41-year-old woman presents to her primary care provider reporting abdominal pain. She reports a three-hour history of right upper quadrant sharp pain that started an hour after her last meal. She denies nausea, vomiting, or changes in her bowel habits. She notes a history of multiple similar episodes of pain over the past two years. Her past medical history is notable for type II diabetes mellitus, major depressive disorder, and obesity. She takes glyburide and sertraline. Her temperature is 98.6°F (37°C), blood pressure is 140/85 mmHg, pulse is 98/min, and respirations are 18/min. On examination, she is tender to palpation in her right upper quadrant. She has no rebound or guarding. Murphy’s sign is negative. No jaundice is noted. The hormone responsible for this patient’s pain has which of the following functions?", "answer": "Promote relaxation of the sphincter of Oddi", "options": {"A": "Increase growth hormone secretion before meals", "B": "Increase pancreatic bicarbonate secretion", "C": "Promote gallbladder relaxation", "D": "Promote migrating motor complexes", "E": "Promote relaxation of the sphincter of Oddi"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 1-year-old boy brought in by his mother presents to his physician for a routine checkup. On examination, the child is happy and playful and meets normal cognitive development markers. However, the child’s arms and legs are not meeting development goals, while his head and torso are. The mother states that the boy gets this from his father. Which of the following is the mutation associated with this presentation?", "answer": "Overactivation of FGFR3", "options": {"A": "FBN1 gene mutation", "B": "Underactivation of FGFR3", "C": "GAA repeat", "D": "Deletion of DMD", "E": "Overactivation of FGFR3"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old man is being evaluated for malaise and fatigability. He says that he hasn’t been able to perform at work, can’t exercise like before, and is constantly tired. He also says that his clothes have ‘become larger’ in the past few months. Past medical history is significant for gastroesophageal reflux disease, which is under control with lifestyle changes. His blood pressure is 110/70 mm Hg, the temperature is 37.0°C (98.6°F), the respiratory rate is 17/min, and the pulse is 82/min. On physical examination, an enlarged, painless, mobile, cervical lymph node is palpable. A complete blood count is performed.\nHemoglobin 9.0 g/dL\nHematocrit 37.7%\nLeukocyte count 5,500/mm3\n Neutrophils 65%\n Lymphocytes 30%\n Monocytes 5%\nMean corpuscular volume 82.2 μm3\nPlatelet count 190,000 mm3\nErythrocyte sedimentation rate 35 mm/h\nC-reactive protein 8 mg/dL\nA biopsy of the lymph node is performed which reveals both multinucleated and bilobed cells. The patient is started on a regimen of drugs for his condition. Echocardiography is performed before treatment is started and shows normal ejection fraction, ventricle function, and wall motion. After 2 rounds of chemotherapy, another echocardiography is performed by protocol, but this time all heart chambers are enlarged, and the patient is suffering from severe exertion dyspnea. Which of the drugs below is most likely responsible for these side effects?", "answer": "Adriamycin", "options": {"A": "Adriamycin", "B": "Bleomycin", "C": "Vinblastine", "D": "Dacarbazine", "E": "Rituximab"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old man presents to the emergency department with severe substernal pain at rest, which radiates to his left arm and jaw. He reports that he has had similar but milder pain several times in the past during strenuous exercise. He had heart transplantation due to dilatory cardiomyopathy 5 years ago with an acute rejection reaction that was successfully treated with corticosteroids. He had been taking 1 mg tacrolimus twice a day for 3.5 years but then discontinued it and had no regular follow-ups. The man does not have a family history of premature coronary artery disease. His blood pressure is 110/60 mm Hg, heart rate is 97/min, respiratory rate is 22/min, and temperature is 37.3°C (99.1°F). On physical examination, the patient is alert, responsive, and agitated. Cardiac auscultation reveals a fourth heart sound (S4) and an irregularly irregular heart rhythm. His ECG shows ST elevation in leads I, II, V5, and V6, and ST depression in leads III and aVF. His complete blood count and lipidogram are within normal limits. The patient’s cardiac troponin I and T levels are elevated. A coronary angiogram reveals diffuse concentric narrowing of all branches of the left coronary artery. What is the most likely causative mechanism of this patient’s cardiac ischemia?", "answer": "Obliterative arteriopathy", "options": {"A": "Vasospasm of distal coronary arteries branches", "B": "Left ventricular hypertrophy", "C": "Obliterative arteriopathy", "D": "Increased oxygen demand due to tachycardia", "E": "Granulomatous vasculitis of coronary arteries"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-hour-old neonate girl is brought to the clinic by her mother because of a blue-spotted skin rash. Her mother says she is from a rural area. She did not receive any prenatal care including vaccinations and prenatal counseling. The neonate does not react to sounds or movements, and on physical examination, a continuous murmur is heard over the left upper sternal border on auscultation. Which of the following cardiac findings is most likely in this patient?", "answer": "Patent ductus arteriosus", "options": {"A": "Coarctation of the aorta", "B": "Mitral valve prolapse", "C": "Patent ductus arteriosus", "D": "Tetralogy of Fallot", "E": "Ventricular septal defect"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man comes to the physician because his wife has noticed that his left eye looks smaller than his right. He has had worsening left shoulder and arm pain for 3 months. He has smoked two packs of cigarettes daily for 35 years. Examination shows left-sided ptosis. The pupils are unequal but reactive to light; when measured in dim light, the left pupil is 3 mm and the right pupil is 5 mm. Which of the following is the most likely cause of this patient's ophthalmologic symptoms?", "answer": "Compression of the stellate ganglion", "options": {"A": "Thrombosis of the cavernous sinus", "B": "Aneurysm of the posterior cerebral artery", "C": "Dissection of the carotid artery", "D": "Compression of the stellate ganglion", "E": "Infiltration of the cervical plexus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old male presents to the emergency department after a motor vehicle accident. The patient is conscious and communicating with hospital personnel. He is in pain and covered in bruises and scrapes. The patient was the driver in a head-on motor vehicle collision. The patient's temperature is 99.5°F (37.5°C), pulse is 112/min, blood pressure is 120/70 mmHg, respirations are 18/min, and oxygen saturation is 99% on room air. A full trauma assessment is being performed and is notable for 0/5 strength in the right upper extremity for extension of the wrist. The patient is started on IV fluids and morphine, and radiography is ordered. The patient has bilateral breath sounds, a normal S1 and S2, and no signs of JVD. His blood pressure 30 minutes later is 122/70 mmHg. Which of the following fractures is most likely in this patient?", "answer": "Midshaft humerus", "options": {"A": "Humeral neck", "B": "Midshaft humerus", "C": "Supracondylar", "D": "Ulnar", "E": "Radial"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old man comes to the physician because of a 3-month history of diffuse muscle pain, malaise, pain in both knees, recurrent episodes of abdominal and chest pain. He has also had a 5-kg (11-lb) weight loss over the past 4 months. Four years ago, he was diagnosed with chronic hepatitis B infection and was started on tenofovir. There are several ulcerations around the ankle and calves bilaterally. Perinuclear anti-neutrophil cytoplasmic antibodies are negative. Urinalysis shows proteinuria and hematuria. Muscle biopsy shows a transmural inflammation of the arterial wall with leukocytic infiltration and fibrinoid necrosis. Which of the following is the most likely diagnosis?", "answer": "Polyarteritis nodosa", "options": {"A": "Giant cell arteritis", "B": "Polyarteritis nodosa", "C": "Granulomatosis with polyangiitis", "D": "Thromboangiitis obliterans", "E": "Microscopic polyangiitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 28-year-old woman presents to a physician with complaints of fever, cough, and cold for the last 2 days. She does not have any other symptoms and she has no significant medical history. She has recently started using combined oral contraceptive pills (OCPs) for birth control. On physical examination, the temperature is 38.3°C (101.0°F), the pulse is 98/min, the blood pressure is 122/80 mm Hg, and the respiratory rate is 14/min. The nasal mucosa and pharynx are inflamed, but there is no purulent discharge. Auscultation of the chest does not reveal any abnormalities. She mentions that she has been a heavy smoker for the last 5 years, smoking about 15–20 cigarettes per day. The physician suggests she should discontinue using combined OCPs and choose an alternative contraception method. Which of the following best explains the rationale behind the physician's suggestion?", "answer": "Smoking is likely to increase the risk of developing deep vein thrombosis and pulmonary embolism in women taking OCPs", "options": {"A": "Smoking inhibits CYP1A2, therefore there is an increased risk of estrogen-related side effects of OCPs", "B": "Smoking induces CYP3A4, therefore OCPs would be ineffective", "C": "Smoking induces CYP1A2, therefore OCPs would be ineffective", "D": "Smoking inhibits CYP3A4, therefore there is an increased risk of progestin-related side effects of OCPs", "E": "Smoking is likely to increase the risk of developing deep vein thrombosis and pulmonary embolism in women taking OCPs"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old man is brought to the emergency department shortly after sustaining injuries in a building fire. On arrival, he appears agitated and has shortness of breath. Examination shows multiple second-degree burns over the chest and abdomen and third-degree burns over the upper extremities. Treatment with intravenous fluids and analgesics is begun. Two days later, the patient is confused. His temperature is 36°C (96.8°F), pulse is 125/min, and blood pressure is 100/58 mm Hg. Examination shows violaceous discoloration and edema of the burn wounds. His leukocyte count is 16,000/mm3. Blood cultures grow gram-negative, oxidase-positive, non-lactose fermenting rods. The causal organism actively secretes a virulence factor that acts primarily via which of the following mechanisms?", "answer": "Inhibition of protein synthesis", "options": {"A": "Inhibition of phagocytosis", "B": "Overwhelming release of cytokines", "C": "Increase in fluid secretion", "D": "Inhibition of protein synthesis", "E": "Inhibition of neurotransmitter release\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-day-old boy is brought to the emergency department because he is found to be febrile and listless. He was born at home to a G1P1 mother without complications, and his mother has no past medical history. On presentation he is found to be febrile with a bulging tympanic membrane on otoscopic examination. Furthermore, he is found to have an abscess around his rectum that discharges a serosanguinous fluid. Finally, the remnants of the umbilical cord are found to be attached and necrotic. Which of the following processes is most likely abnormal in this patient?", "answer": "Neutrophil migration", "options": {"A": "Actin remodeling", "B": "Antibody class switching", "C": "Microtubule organization", "D": "Neutrophil migration", "E": "Reactive oxygen species production"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old woman, G1P0, visits her gynecologist’s office for a routine prenatal checkup. During her quadruple screening test, her alpha-fetoprotein levels were increased while the β-hCG and pregnancy-associated plasma protein were decreased. There is also evidence of increased nuchal translucency on the scanning of the male fetus. A confirmatory test indicates signs of a genetic syndrome. The woman is counseled that her child will most likely have a severe intellectual disability. Physical features of this condition include polydactyly, cleft palate, micrognathia and clenched fists. This genetic condition also affects the formation of the brain and can lead to stillbirth. Most babies do not survive beyond the first year of life. Which of the following is responsible for this type of genetic syndrome?", "answer": "Nondisjunction of chromosomes", "options": {"A": "In utero infections", "B": "Error in metabolism", "C": "Genomic imprinting", "D": "Nondisjunction of chromosomes", "E": "Autosomal dominant genes"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old boy comes to the emergency department because of painful urination and urethral discharge for 3 days. He has multiple sexual partners and only occasionally uses condoms. His vital signs are within normal limits. The result of nucleic acid amplification testing for Neisseria gonorrhoeae is positive. The patient requests that his parents not be informed of the diagnosis. Which of the following initial actions by the physician is most appropriate?", "answer": "Administer intramuscular and oral antibiotics", "options": {"A": "Order urinary PCR testing in two weeks", "B": "Perform urethral swab culture for antibiotic sensitivities", "C": "Request parental consent prior to prescribing antibiotics", "D": "Discuss results with patient's primary care physician", "E": "Administer intramuscular and oral antibiotics"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 30-year-old man comes to the emergency department because of fever and productive cough for the past 4 days. During this period, he has had shortness of breath and chest pain that is worse on inspiration. He also reports fatigue and nausea. He has refractory schizophrenia and recurrent asthma attacks. He used to attend college but was expelled after threatening to harm one of his professors 2 months ago. His temperature is 38.5°C (101.3°F), pulse is 90/min, respirations are 20/min, and blood pressure is 120/80 mm Hg. Crackles and bronchial breath sounds are heard on auscultation of the left lung. Laboratory studies show:\nHemoglobin 13.5 g/dL\nLeukocyte count 1,100/mm3\nSegmented neutrophils 5%\nEosinophils 0%\nLymphocytes 93%\nMonocytes 2%\nPlatelet count 260,000/mm3\nWhich of the following medications is this patient most likely taking?\"", "answer": "Clozapine", "options": {"A": "Clozapine", "B": "Olanzapine", "C": "Haloperidol", "D": "Risperidone", "E": "Chlorpromazine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old woman comes to the clinic for blisters on both hands. The patient has a past medical history of asthma, eczema, and a car accident 2 years ago where she sustained a concussion. She also reports frequent transient episodes of blurred vision that clear with artificial tears. When asked about her blisters, the patient claims she was baking yesterday and forgot to take the pan out with oven gloves. Physical examination demonstrates weeping blisters bilaterally concentrated along the palmar surfaces of both hands and decreased pinprick sensation along the arms bilaterally. What is the most likely explanation of this patient’s symptoms?", "answer": "Syringomyelia at the cervico-thoracic region", "options": {"A": "Brain contusion", "B": "Multiple sclerosis", "C": "Sjogren syndrome", "D": "Syringomyelia at the cervico-thoracic region", "E": "Syringomyelia at the lumbar region"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old man presents with heartburn for the past couple of weeks. He says he feels a burning sensation in his chest, at times reaching his throat, usually worse after eating spicy foods. He is overweight and actively trying to lose weight. He also has tried other lifestyle modifications for the past couple of months, but symptoms have not improved. He denies any history of cough, difficulty swallowing, hematemesis, or melena. The patient says he often drinks a can of beer in the evening after work and does not smoke. His blood pressure is 124/82 mm Hg, pulse is 72/min and regular, and respiratory rate is 14/min. Abdominal tenderness is absent. Which of the following is the next best step in the management of this patient?", "answer": "Start omeprazole.", "options": {"A": "Start omeprazole.", "B": "Start sucralfate.", "C": "Start famotidine.", "D": "Start oral antacids.", "E": "H. pylori screening"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old man is brought to his primary care physician by his wife because she is concerned that he has become more confused over the past month. Specifically, he has been having difficulty finding words and recently started forgetting the names of their friends. She became particularly worried when he got lost in their neighborhood during a morning walk. Finally, he has had several episodes of incontinence and has tripped over objects because he \"does not lift his feet off the ground\" while walking. He has a history of hypertension and diabetes but has otherwise been healthy. His family history is significant for many family members with early onset dementia. Which of the following treatments would most likely be effective for this patient?", "answer": "Placement of shunt", "options": {"A": "Better control of diabetes and hypertension", "B": "Galantamine", "C": "Placement of shunt", "D": "Selegiline", "E": "Tetrabenazine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old veteran with a history of hypertension, diabetes, and end-stage renal disease presents with nausea, vomiting, and abdominal pain. The patient was found to have a small bowel obstruction on CT imaging. He is managed conservatively with a nasogastric tube placed for decompression. After several days in the hospital, the patient’s symptoms are gradually improving. Today, he complains of left leg swelling. On physical exam, the patient has a swollen left lower extremity with calf tenderness on forced dorsiflexion of the ankle. An ultrasound confirms a deep vein thrombus. An unfractionated heparin drip is started. What should be monitored to adjust heparin dosing?", "answer": "Activated partial thromboplastin time", "options": {"A": "Prothrombin time", "B": "Activated partial thromboplastin time", "C": "Internationalized Normal Ratio (INR)", "D": "Creatinine level", "E": "Liver transaminase levels"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old gravida 2 para 2 presents to a medical clinic to discuss contraception options. She had a normal vaginal delivery of a healthy baby boy with no complications 2 weeks ago. She is currently doing well and is breastfeeding exclusively. She would like to initiate a contraceptive method other than an intrauterine device, which she tried a few years ago, but the intrauterine device made her uncomfortable. The medical history includes migraine headaches without aura, abnormal liver function with mild fibrosis, and epilepsy as a teenager. She sees multiple specialists due to her complicated history, but is stable and takes no medications. There is a history of breast cancer on the maternal side. On physical examination, the temperature is 36.5°C (97.7°F), the blood pressure is 150/95 mm Hg, the pulse is 89/min, and the respiratory rate is 16/min. After discussing the various contraceptive methods available, the patient decides to try combination oral contraceptive pills. Which of the following is an absolute contraindication to start the patient on combination oral contraceptive pills?", "answer": "Breastfeeding", "options": {"A": "Breastfeeding", "B": "History of epilepsy", "C": "Elevated blood pressure", "D": "Mild liver fibrosis", "E": "Migraine headaches"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old African American woman with a history of Addison's disease presents with widespread, symmetric hypopigmented patches and macules overlying her face and shoulders. After a thorough interview and using a Wood’s lamp to exclude fungal etiology, vitiligo is suspected. Complete blood count shows leukocytes 6,300, Hct 48.3%, Hgb 16.2 g/dL, mean corpuscular volume (MCV) 90 fL, and platelets 292. Which of the statements below about this patient’s suspected disease is correct?", "answer": "The course usually is slowly progressive with spontaneous repigmentation in 15% of patients.", "options": {"A": "The course usually is slowly progressive with spontaneous repigmentation in 15% of patients.", "B": "The disease is relapsing and remitting with complete interval repigmentation.", "C": "Keloid formation is associated with regions of depigmentation.", "D": "Vitiligo is self-limited and will resolve in 8-14 weeks.", "E": "Topical corticosteroids are inappropriate for patients with limited disease."}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 46-year-old woman comes to the physician for a follow-up examination after a Pap smear showed atypical squamous cells. A colposcopy-directed biopsy of the cervix shows evidence of squamous cell carcinoma. The malignant cells from this lesion are most likely to drain into which of the following group of lymph nodes?", "answer": "Internal iliac", "options": {"A": "Internal iliac", "B": "Right supraclavicular", "C": "Inferior mesenteric", "D": "Superficial inguinal", "E": "Left supraclavicular"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 29-year-old G2P1001 presents to her obstetrician’s office complaining of dyspareunia. She endorses ongoing vaginal dryness resulting in uncomfortable intercourse over the last month. In addition, she has noticed a gritty sensation in her eyes as well as difficulty tasting food and halitosis. She denies pain with urination and defecation. Her medications include a daily multivitamin, folic acid, and over-the-counter eye drops. The patient’s temperature is 98.6°F (37.0°C), pulse is 70/min, blood pressure is 121/80 mmHg, and respirations are 13/min. Physical exam is notable for a well-appearing female with fullness in the bilateral cheeks and reduced salivary pool. For which of the following is the patient’s fetus at increased risk?", "answer": "Heart block", "options": {"A": "Macrosomia", "B": "Neonatal hypoglycemia", "C": "Heart block", "D": "Pulmonary hypertension", "E": "Meconium aspiration"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A healthy mother gives birth to a child at 40 weeks of gestation. On examination, the child has ambiguous genitalia. A karyotype analysis reveals the presence of a Y chromosome. Additional workup reveals the presence of testes and a normal level of serum luteinizing hormone (LH) and testosterone. Which of the following is the most likely cause of this patient’s condition?", "answer": "5-alpha reductase deficiency", "options": {"A": "Androgen receptor deficiency", "B": "Failed migration of neurons producing gonadotropin releasing hormone (GnRH)", "C": "Presence of two X chromosomes", "D": "5-alpha reductase deficiency", "E": "Aromatase deficiency"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old man who was recently placed on TMP-SMX for a urinary tract infection presents to urgent care with a new rash. The vital signs include: blood pressure 121/80 mm Hg, pulse 91/min, respiratory rate 18/min, and temperature 36.7°C (98.2°F). Physical examination reveals a desquamative skin covering both of his lower extremities. A basic chemistry panel reveal sodium 139 mmol/L, potassium 3.8 mmol/L, chloride 110 mmol/L, carbon dioxide 47, blood urea nitrogen 23 mg/dL, creatinine 0.9 mg/dL, and glucose 103 mg/dL. Which of the following is the most likely diagnosis?", "answer": "Toxic epidermal necrolysis (TEN)", "options": {"A": "Dermatitis herpetiformis", "B": "Steven-Johnson syndrome (SJS)", "C": "Seborrheic dermatitis", "D": "Atopic dermatitis", "E": "Toxic epidermal necrolysis (TEN)"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old man with a history of type I diabetes presents to the emergency room in respiratory distress. His respirations are labored and deep, and his breath odor is notably fruity. Which of the following laboratory results would you most expect to find in this patient?", "answer": "Increased urine H2PO4-", "options": {"A": "Increased serum HCO3-", "B": "Decreased serum H+", "C": "Decreased urine H+", "D": "Increased urine HCO3-", "E": "Increased urine H2PO4-"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-year-old boy presents to the ED with a one day history of severe right eye pain accompanied by nausea, vomiting, and headache. He is afebrile and he appears to be alert despite being irritable. Three days ago an ophthalmologist prescribed eye drops for his right eye but his parents do not know the name of the medication. On exam, his right eye is hard to palpation and moderately dilated. His left eye is unremarkable. What is the mechanism of action of the medication that most likely provoked this acute presentation?", "answer": "Muscarinic antagonist inhibiting pupillary sphincter muscle contraction", "options": {"A": "Muscarinic antagonist inhibiting pupillary sphincter muscle contraction", "B": "Iris neovascularization", "C": "M3 agonist causing ciliary muscle contraction", "D": "Agonist of prostaglandin F receptor increasing aqueous fluid production", "E": "Alpha-adrenergic agonist increasing aqueous fluid production"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old woman presents to the clinic complaining of a 9-month history of weight loss, fatigue, and a general sense of malaise. She additionally complains of an unusual sensation in her chest upon rapidly rising from a supine to a standing position. Current vitals include a temperature of 36.8°C (98.2°F), pulse of 72/min, blood pressure of 118/63 mm Hg, and a respiratory rate of 15/min. Her BMI is 21 kg/m2. Auscultation demonstrates an early-mid diastole low-pitched sound at the apex of the heart. A chest X-ray reveals a poorly demarcated abnormality in the heart and requires CT imaging for further analysis. What would most likely be seen on CT imaging?", "answer": "Tumor within the left atria", "options": {"A": "Tumor within the right atria", "B": "Fistula between the right and left atria", "C": "Normal cardiac imaging", "D": "Tumor within the left atria", "E": "Connection between the pulmonary artery and aorta"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old man presents to the physician with fever and malaise for 4 days. He has headaches and joint pain. A pruritic rash appeared on the trunk yesterday. He had blood in his ejaculate twice. His hearing has become partially impaired. There is no history of serious illnesses or the use of medications. Ten days ago, he traveled to Brazil where he spent most of the time outdoors in the evenings. He did not use any control measures for mosquito bites. His temperature is 38.2℃ (100.8℉); the pulse is 88/min; the respiratory rate is 13/min, and the blood pressure is 125/60 mm Hg. Conjunctival suffusion is noted. A maculopapular rash is present over the trunk and proximal extremities without the involvement of the palms or soles. Several joints of the hands are tender to palpation. The abdomen is soft with no organomegaly. A peripheral blood smear shows no pathogenic organisms. Which of the following is the most likely diagnosis?", "answer": "Zika virus disease", "options": {"A": "Chagas disease", "B": "Malaria", "C": "Rocky Mountain spotted fever", "D": "Whipple’s disease", "E": "Zika virus disease"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old Japanese female presents with flu-like symptoms and weak pulses in her upper extremities. An angiogram reveals granulomatous inflammation of the aortic arch. Which of the following disease processes is most similar to this patient's disease?", "answer": "Temporal arteritis", "options": {"A": "Temporal arteritis", "B": "Polyarteritis nodosa", "C": "Kawasaki disease", "D": "Buerger's disease", "E": "Infectious vasculitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-month-old girl is brought to the emergency department in respiratory distress after her parents noticed that she was having difficulty breathing. They say that she developed a fever 2 days ago and subsequently developed increasing respiratory difficulty, lethargy, and productive cough. On presentation, her temperature is 103°F (39.5°C), blood pressure is 84/58 mmHg, pulse is 141/min, and respirations are 48/min. Physical exam reveals subcostal retractions and consolidation in the right lower lung field. She is also found to have coarse facial features and restricted joint movement. Serum laboratory tests reveal abnormally elevated levels of lysosomal enzymes circulating in the blood. The enzyme that is most likely defective in this patient has which of the following substrates?", "answer": "Mannose", "options": {"A": "Ceremide", "B": "Dermatan sulfate", "C": "Galactocerebroside", "D": "Mannose", "E": "Sphingomyelin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old woman comes to the physician because of a 4-month history of intermittent lower abdominal cramps associated with diarrhea, bloating, and mild nausea. During this period, she has had a 5-kg (11-lb) weight loss. She feels like she cannot fully empty her bowels. She has no history of serious illness. She has a high-fiber diet. Her father is of Ashkenazi Jewish descent. She appears well. Her temperature is 36.9°C (98.5°F), pulse is 90/min, and blood pressure is 130/90 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no murmurs, rubs, or gallops. Abdominal examination shows mild tenderness to palpation in the right lower quadrant without guarding or rebound. Bowel sounds are normal. Test of the stool for occult blood is negative. Her hemoglobin concentration is 10.5 g/dL, leukocyte count is 12,000 mm3, platelet count is 480,000 mm3, and erythrocyte sedimentation rate is 129 mm/h. A barium enema shows ulceration and narrowing of the right colon. Which of the following is the most likely diagnosis?", "answer": "Crohn disease", "options": {"A": "Ulcerative colitis", "B": "Celiac disease", "C": "Intestinal carcinoid tumor", "D": "Crohn disease", "E": "Diverticulitis\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old man with dilated cardiomyopathy is admitted to the cardiac care unit (CCU) because of congestive heart failure exacerbation. A medical student wants to determine the flow velocity across the aortic valve. She estimates the cross-sectional area of the valve is 5 cm2and the volumetric flow rate is 55 cm3/s. Which of the following best represents this patient's flow velocity across the aortic valve?", "answer": "0.11 m/s", "options": {"A": "0.009 m/s", "B": "0.0009 m/s", "C": "2.75 m/s", "D": "0.11 m/s", "E": "0.09 m/s"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old woman, gravida 2, para 1, at 10 weeks' gestation comes to the emergency department for vaginal bleeding, cramping lower abdominal pain, and dizziness. She also has had fevers, chills, and foul-smelling vaginal discharge for the past 2 days. She is sexually active with one male partner, and they use condoms inconsistently. Pregnancy and delivery of her first child were uncomplicated. She appears acutely ill. Her temperature is 38.9°C (102°F), pulse is 120/min, respirations are 22/min, and blood pressure is 88/50 mm Hg. Abdominal examination shows moderate tenderness to palpation over the lower quadrants. Pelvic examination shows a tender cervix that is dilated with clots and a solid bloody mass within the cervical canal. Her serum β-human chorionic gonadotropin concentration is 15,000 mIU/mL. Pelvic ultrasound shows an intrauterine gestational sac with absent fetal heart tones. Which of the following is the most appropriate next step in management?", "answer": "Intravenous clindamycin and gentamicin followed by suction and curettage", "options": {"A": "Intravenous clindamycin and gentamicin followed by oral misoprostol", "B": "Oral clindamycin followed by outpatient follow-up in 2 weeks", "C": "Intravenous clindamycin and gentamicin followed by suction and curettage", "D": "Intravenous clindamycin and gentamycin followed by close observation", "E": "Oral clindamycin followed by suction curettage"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl presents to the family doctor with fever, headache, sore throat, dry cough, myalgias, and weakness. Her symptoms began acutely 2 days ago. On presentation, her blood pressure is 110/80 mm Hg, heart rate is 86/min, respiratory rate is 18/min, and temperature is 39.0°C (102.2°F). Physical examination reveals conjunctival injection and posterior pharyngeal wall erythema. Rapid diagnostic testing of a throat swab for influenza A+B shows positive results. Which of the following statements is true regarding the process of B cell clonal selection and the formation of specific IgG antibodies against influenza virus antigens in this patient?", "answer": "After somatic hypermutation, only a small amount of B cells antigen receptors have increased affinity for the antigen.", "options": {"A": "The first event that occurs after B lymphocyte activation is V(D)J recombination.", "B": "During antibody class switching, variable region of antibody heavy chain changes, and the constant one stays the same.", "C": "Deletions are the most common form of mutations that occur during somatic hypermutation in this patient’s B cells.", "D": "V(D)J recombination results in the formation of a B cell clone, which produces specific antibodies against influenza virus antigens.", "E": "After somatic hypermutation, only a small amount of B cells antigen receptors have increased affinity for the antigen."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old man comes to the physician because of a whistling sound during respiration for the past 3 weeks. He reports that the whistling is becoming louder, and is especially loud when he exercises. He says the noise is frustrating for him. Six months ago, the patient underwent outpatient treatment for an uncomplicated nasal fracture after being hit in the nose by a high-velocity stray baseball. Since the accident, the patient has been taking aspirin for pain. He has a history of asymptomatic nasal polyps. His temperature is 37°C (98.6°F), pulse is 70/min, respirations are 12/min, and blood pressure is 110/70 mm Hg. Physical examination shows no abnormalities. Which of the following would have prevented the whistling during respiration?", "answer": "Nasal septal hematoma drainage", "options": {"A": "Nasal septal hematoma drainage", "B": "Nasal polyp removal", "C": "Antibiotic therapy", "D": "Rhinoplasty", "E": "Septoplasty"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old boy with behavioral changes is brought in by his concerned parents. The patient’s parents say that he has been acting very odd and having difficulty academically for the past 4 months. The patient says that he has been worried and distracted because he is certain the government is secretly recording him although he cannot provide a reason why. He mentions that he does feel depressed sometimes and no longer gets joy out of playing the guitar and his other previous activities. He has no significant past medical history. The patient denies any history of smoking, alcohol consumption, or recreational drug use. He is afebrile, and his vital signs are within normal limits. Physical examination is unremarkable. On mental status examination, the patient is slightly disheveled and unkempt. He has a disorganized monotonous speech pattern. He expresses tangential thinking and has a flat affect. During the exam, it is clear that he suffers from auditory hallucinations. Which of the following is the most likely diagnosis in this patient?", "answer": "Schizophreniform disorder", "options": {"A": "Brief psychotic disorder", "B": "Schizophreniform disorder", "C": "Schizophrenia", "D": "Schizoaffective disorder", "E": "Schizotypal personality disorder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 1-month-old boy is brought to the emergency department by his parents for recent episodes of non-bilious projectile vomiting and refusal to eat. The boy had no problem with passing meconium or eating at birth; he only started having these episodes at 3 weeks old. Further history reveals that the patient is a first born male and that the boy’s mother was treated with erythromycin for an infection late in the third trimester. Physical exam reveals a palpable mass in the epigastrum. Which of the following mechanisms is likely responsible for this patient’s disorder?", "answer": "Hypertrophy of smooth muscle", "options": {"A": "Defect of lumen recanalization", "B": "Hypertrophy of smooth muscle", "C": "Intestinal vascular accident", "D": "Neural crest cell migration failure", "E": "Pancreatic fusion abnormality"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old man presents with difficulty breathing and blurred vision in the left eye. No significant past medical history or current medications. He has had more than 6 sexual partners (both men and women) and did not use any form of protection during sexual intercourse. No significant family history. Upon physical examination, the patient has crackles in all lobes bilaterally. Ophthalmologic exam reveals a single white lesion in the left eye with an irregular, feathery border, as well as evidence of retinal edema and necrosis. A rapid HIV test is positive. What is the mechanism of action of the drug that can be given to treat the ocular symptoms in this patient?", "answer": "Guanosine analog that preferably inhibits viral DNA polymerase", "options": {"A": "Blocks CCR5 receptor preventing viral entry", "B": "Guanosine analog that preferably inhibits viral DNA polymerase", "C": "A neuraminidase inhibitor preventing release of viral progeny", "D": "Prevents viral uncoating", "E": "Inhibits A-site tRNA binding during translation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 9-year-old boy is brought to the emergency department by ambulance due to difficulty breathing. On presentation he is found to be straining to breathe. Physical exam reveals bilateral prolonged expiratory wheezing, difficulty speaking, and belly breathing. Radiographs also reveal hyperinflation of the lungs. He is given oxygen as well as albuterol, which begins to reverse the flow limitation in the airway segments of this patient. The airway segment that is most susceptible to this type of flow limitation has which of the following characteristics?", "answer": "Distal most extent of smooth muscle", "options": {"A": "Contains c-shaped hyaline cartilage rings", "B": "Contains mucous producing goblet cells", "C": "Distal most extent of smooth muscle", "D": "Lined by only simple cuboidal cells", "E": "Lined by type I and type II pneumocytes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old man comes to the physician because of a 3-month history of fatigue, polyuria, and blurry vision. His BMI is 33 kg/m2 and his blood pressure is 147/95 mm Hg. Laboratory studies show a serum glucose concentration of 192 mg/dL and hemoglobin A1c concentration of 7.2%. Urinalysis shows 1+ glucose, 1+ protein, and no ketones. Which of the following is the most appropriate pharmacotherapy to prevent cardiovascular disease in this patient?", "answer": "Lisinopril therapy", "options": {"A": "Lisinopril therapy", "B": "Sleeve gastrectomy", "C": "Aspirin therapy", "D": "Insulin therapy", "E": "Gemfibrozil therapy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Background and Methods:\nAldosterone is important in the pathophysiology of heart failure. In a double-blind study, we enrolled 1,663 patients who had NYHA class III or IV heart failure, a left ventricular ejection fraction of no more than 35%, and who were being treated with an angiotensin-converting-enzyme inhibitor, a loop diuretic, and in most cases digoxin. A total of 822 patients were randomly assigned to receive 25 mg of spironolactone daily and 841 to receive placebo. The primary endpoint was death from all causes.\nResults:\nThe trial was discontinued early, after a mean follow-up period of 24 months, because an interim analysis determined that spironolactone was efficacious. There were 386 deaths in the placebo group (46%) and 284 in the spironolactone group (35%; relative risk of death, 0.70; 95% confidence interval, 0.60 to 0.82; P<0.001). This 30% reduction in the risk of death among patients in the spironolactone group was attributed to a lower risk of both death from progressive heart failure and sudden death from cardiac causes. The frequency of hospitalization for worsening heart failure was 35% lower in the spironolactone group than in the placebo group (relative risk of hospitalization, 0.65; 95% confidence interval, 0.54 to 0.77; P<0.001). In addition, patients who received spironolactone had a significant improvement in the symptoms of heart failure, as assessed on the basis of the New York Heart Association functional class (P<0.001). Gynecomastia or breast pain was reported in 10% of men who were treated with spironolactone, as compared with 1 percent of men in the placebo group (P<0.001). The incidence of serious hyperkalemia was minimal in both groups of patients.\nTo which of the following patients are the results of this clinical trial applicable?", "answer": "A 56-year-old male with NYHA class III heart failure with an LVEF of 32%, current taking lisinopril, furosemide, and digoxin", "options": {"A": "An 82-year-old female with NYHA class II heart failure with an LVEF of 22%, taking lisinopril, furosemide, and digoxin", "B": "A 65-year-old male with newly diagnosed NYHA class IV heart failure and a LVEF of 21%, about to begin medical therapy", "C": "A 56-year-old male with NYHA class III heart failure with an LVEF of 32%, current taking lisinopril, furosemide, and digoxin", "D": "An 86-year-old female recently found to have an LVEF of 34%, currently taking furosemide and carvedilol", "E": "A 78-year-old male with NYHA class II heart failure and LVEF 36%"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 56-year-old man presents for an annual checkup. He has no complaints at the moment of presentation. He was diagnosed with diabetes mellitus a year ago and takes metformin 1000 mg per day. The patient also has a history of postinfectious myocarditis that occurred 15 years ago with no apparent residual heart failure. His family history is unremarkable. He has a 15-pack-year history of smoking, but he currently does not smoke. He is a retired weightlifting athlete who at the present works as a coach and continues to work out. His BMI is 29 kg/m2. The blood pressure is 120/85 mm Hg, heart rate is 85/min, respiratory rate is 14/min, and temperature is 36.6℃ (97.9℉). Physical examination is only remarkable for an increased adiposity. The ECG is significant for increased R amplitude in leads I, II, and V3-6 and an incomplete left bundle branch block. Which of the following is most likely included in the treatment regimen of this patient?", "answer": "Fosinopril", "options": {"A": "No management is required since the patient is asymptomatic", "B": "Diltiazem", "C": "Amlodipine", "D": "Furosemide", "E": "Fosinopril"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-year-old male presents to the emergency department after falling from his scooter. The patient reports that he fell sideways off the scooter as he rounded a curve in the road, and he describes dull, aching pain along his left side where he hit the ground. The patient’s parents report that he has never had any serious injury but that he has always seemed to bruise easily, especially after he started playing youth soccer this fall. His parents deny that he has ever had nosebleeds or bleeding from the gums, and they have never seen blood in his stool or urine. His mother notes that her brother has had similar problems. On physical exam, the patient has extensive bruising of the lateral left thigh and tenderness to palpation. Laboratory tests are performed and reveal the following:\n\nHemoglobin: 14 g/dL\nHematocrit: 41%\nMean corpuscular volume: 89 µm3\nReticulocyte count: 0.8%\nLeukocyte count: 4,700/mm3\nProthrombin time (PT): 13 seconds\nPartial thromboplastin time (PTT): 56 seconds\nBleeding time (BT): 4 minutes\n\nWhich of the following is the most likely underlying pathophysiology of this patient's presentation?", "answer": "Factor VIII deficiency", "options": {"A": "Factor VIII deficiency", "B": "Factor IX deficiency", "C": "Factor VIII antigen deficiency", "D": "GP1b deficiency", "E": "Anti-platelet antibodies"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 38-year-old man comes to the physician because of fever, malaise, cough, and shortness of breath for 2 months. He has had a 4-kg (9-lb) weight loss during the same period. He works at a flour mill and does not smoke cigarettes. His temperature is 38.1°C (100.6°F) and pulse oximetry shows 95% on room air. Diffuse fine crackles are heard over both lung fields. A chest x-ray shows patchy reticulonodular infiltrates in the mid and apical lung fields bilaterally. A photomicrograph of a lung biopsy specimen is shown. Which of the following cytokines have the greatest involvement in the pathogenesis of the lesion indicated by the arrow?", "answer": "Interferon gamma and interleukin-2", "options": {"A": "Tumor necrosis factor alpha and interleukin-4", "B": "Interferon gamma and interleukin-2", "C": "Interferon alpha and interleukin-1", "D": "Interleukin-4 and interleukin-10", "E": "Transforming growth factor beta and interleukin-12"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A group of investigators is examining the effect of the drug orlistat as an adjunct therapy to lifestyle modification on weight loss in obese volunteers. 800 obese participants were randomized to receive orlistat in addition to counseling on lifestyle modification and 800 obese participants were randomized to receive counseling on lifestyle modification alone. At the conclusion of the study, the investigators found that patients who underwent combined therapy lost a mean of 8.2 kg (18.1 lb), whereas patients counseled on lifestyle modification alone lost a mean of 4.3 kg (9.5 lb) (p < 0.001). The investigators also observed that of the 120 participants who did not complete the study, 97 participants were in the lifestyle modification group and 23 participants were in the combination group. Based on this information, the investigators should be most concerned about which of the following?", "answer": "Attrition bias", "options": {"A": "Error in randomization", "B": "Lead-time bias", "C": "Attrition bias", "D": "Nonresponse bias", "E": "Confounding bias"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old girl is brought to the physician because of a 1-week history of malaise and chest pain. Three weeks ago, she had a sore throat that resolved without treatment. Her temperature is 38.7°C (101.7°F). Examination shows several subcutaneous nodules on her elbows and wrist bilaterally and a new-onset early systolic murmur best heard at the apex in the left lateral position. An endomysial biopsy is most likely to show which of the following?", "answer": "Fibrinoid necrosis with histiocytic infiltrate", "options": {"A": "Coagulative necrosis with neutrophilic infiltrate", "B": "Fibrinoid necrosis with histiocytic infiltrate", "C": "Deposits of misfolded protein aggregates", "D": "Myocardial infiltration with eosinophilic proteins", "E": "Fibrosis with myofibrillar disarray"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A study of a new antihypertensive drug that affects glomerular filtration rate is being conducted. Infusion of drug X causes constriction of the efferent arteriole. After infusion of the drug, the following glomerular values are obtained from an experimental subject: hydrostatic pressure of the glomerular capillary (PGC) of 48 mm Hg, oncotic pressure of the glomerular capillary (πGC) of 23 mm Hg, hydrostatic pressure of Bowman’s space (PBS) of 10 mm Hg, and oncotic pressure of Bowman’s space (πBS) of 0 mm Hg. Which of the following best measures net filtration pressure in this participant?", "answer": "15 mm Hg", "options": {"A": "15 mm Hg", "B": "35 mm Hg", "C": "61 mm Hg", "D": "0 mm Hg", "E": "81 mm Hg"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old woman comes to the physician because of worsening mental status over the past month. Her husband reports that she was initially experiencing lapses in memory but has recently started having difficulties performing activities of daily living. She appears withdrawn and avoids eye contact. Examination shows diffuse involuntary muscle jerking that can be provoked by loud noises. A cerebrospinal fluid analysis shows elevated concentration of 14-3-3 protein. Four months later, the patient dies. Pathologic examination of the brain on autopsy is most likely to show which of the following findings?", "answer": "Spongiform vacuolation of the cortex", "options": {"A": "Degeneration of the substantia nigra pars compacta", "B": "Marked atrophy of caudate and putamen", "C": "Focal inflammatory demyelination and gliosis", "D": "Deposits of amyloid beta peptides", "E": "Spongiform vacuolation of the cortex"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man comes to the physician because of fatigue and nausea for 1 week. Over the past six months, he has had to get up twice every night to urinate. Occasionally, he has had discomfort during urination. He has arterial hypertension. His father died of renal cell carcinoma. Current medications include ramipril. His temperature is 37.3°C (99.1°F), pulse is 88/min, and blood pressure is 124/78 mm Hg. The abdomen is soft and nontender. Cardiac and pulmonary examinations show no abnormalities. Rectal examination shows a symmetrically enlarged and smooth prostate. Serum studies show:\nHemoglobin 14.9 g/dL\nLeukocyte count 7500/mm3\nPlatelet count 215,000/mm3\nSerum\nNa+ 136 mEq/L\nCl- 101 mEq/L\nK+ 4.9 mEq/L\nHCO3- 23 mEq/L\nGlucose 95 mg/dL\nUrea nitrogen 25 mg/dL\nCreatinine 1.9 mg/dL\nPSA 2.1 ng/mL (normal <4 ng/mL)\nUrine\nBlood negative\nProtein 1+\nGlucose negative\nRBC casts negative\nWhich of the following is the most appropriate next step in management?\"", "answer": "Renal ultrasonography", "options": {"A": "Four-glass test", "B": "CT scan of the abdomen and pelvis", "C": "Transrectal ultrasonography", "D": "Renal ultrasonography", "E": "Ureteral stenting"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old man comes to the physician because of right-sided painless scrotal swelling that he noticed yesterday while taking a shower. He is currently sexually active with two female partners and uses condoms inconsistently. He immigrated to the US from Argentina 2 years ago. His immunization records are unavailable. He has smoked one pack of cigarettes daily for the last 5 years. He is 170 cm (5 ft 7 in) tall and weighs 70 kg (154 lb); BMI is 24.2 kg/m2. He appears healthy and well nourished. His temperature is 37°C (98.6°F), pulse is 72/min, and blood pressure is 125/75 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft with dull lower abdominal discomfort. Testicular examination shows a solid mass in the right testis that is firm and nontender. A light held behind the scrotum does not shine through. The mass is not reduced when the patient is in a supine position. The remainder of the physical examination shows no abnormalities. Which of the following is the most likely diagnosis in this patient?", "answer": "Testicular tumor", "options": {"A": "Orchitis", "B": "Hydrocele testis", "C": "Scrotal hernia", "D": "Testicular torsion", "E": "Testicular tumor"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Two days after undergoing an emergency laparotomy following a motor vehicle collision, a 37-year-old man has increased thirst. Examination shows dry mucous membranes and decreased skin turgor. A review of his chart shows his urine output to be in excess of his fluid intake. Laboratory studies show a serum sodium concentration of 151 mEq/L and urine osmolality of 110 mOsmol/kg H2O. One hour after the administration of desmopressin, the serum sodium concentration is 146 mEq/L and urine osmolality is 400 mOsmol/kg H2O. One week later, his laboratory values are within normal limits. This patient's condition was most likely caused by damage to which of the following structures?", "answer": "Posterior pituitary", "options": {"A": "Posterior pituitary", "B": "Adrenal cortex", "C": "Proximal renal tubule", "D": "Collecting duct", "E": "Supraoptic nucleus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 10-year-old girl is brought to the emergency department because of lower abdominal pain for the past 12 hours. The pain has progressively worsened and was accompanied by occasional episodes of diarrhea. She has vomited twice. Her mother has Crohn disease. Her temperature is 38.1°C (100.6°F), pulse is 95/min, respirations are 20/min, and blood pressure is 110/70 mm Hg. The abdomen is soft, and there is mild tenderness to palpation in the right lower quadrant without rebound or guarding. Bowel sounds are normal. Her hemoglobin concentration is 13.0 g/dL, leukocyte count is 12,800/mm3, and platelet count is 345,000/mm3. Urine dipstick is negative for nitrites and leukocyte esterase. Urinalysis shows 3 WBC/hpf and no RBCs. Which of the following is the most appropriate next step in management?", "answer": "Ultrasound of the abdomen", "options": {"A": "Ultrasound of the abdomen", "B": "Colonoscopy", "C": "CT scan of the abdomen", "D": "X-ray of the abdomen", "E": "MRI of the abdomen"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old man comes to the emergency department with fatigue and palpitations for several weeks. An ECG shows atrial fibrillation. Echocardiography shows thrombus formation in the left atrium. Which of the following organs is most likely to continue to function in the case of an embolic event?", "answer": "Liver", "options": {"A": "Spleen", "B": "Brain", "C": "Kidney", "D": "Liver", "E": "Colon"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old female patient with a history of schizophrenia, type 2 diabetes mellitus, and hypothyroidism comes to clinic stating she would like to be put back on a medication. She recently stopped taking her haloperidol as it made it hard for her to \"sit still.\" She requests to be put on olanzapine as a friend from a support group said it was helpful. Why should this medication be avoided in this patient?", "answer": "The patient has type 2 diabetes", "options": {"A": "The patient is at a high risk for torsades de pointes", "B": "There is a high risk for retinopathy", "C": "The patient has type 2 diabetes", "D": "The patient may develop galactorrhea", "E": "Tardive dyskinesia will likely result from the prolonged use of olanzapine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 16-year-old girl presents to her physician with itching, soreness, and irritation in the vulvar region. She reports that these episodes have occurred 6–7 times a year since the age of 5. She used to treat these symptoms with topical ketoconazole cream, but this time it failed to help. She also has had several episodes of oral candidiasis in the past. She is not sexually active and does not take any medication. Her vital signs are as follows: the blood pressure is 115/80 mm Hg, the heart rate is 78/min, the respiratory rate is 15/min, and the temperature is 35.5°C (97.7°F). Examination shows vulvovaginal erythema with cottage cheese-like plaques and an intact hymen. Wet mount microscopy is positive for yeast. Along with a swab culture, the physician orders a dihydrorhodamine test and myelin peroxidase staining for a suspected primary immunodeficiency. The dihydrorhodamine test is positive, and the myeloperoxidase staining reveals diminished staining. Which of the following best describes this patient’s condition?", "answer": "The patient is likely to have another immune impairment besides the one for which she was tested.", "options": {"A": "The patient’s phagocytes are unable to generate an oxidative burst to kill intracellular bacteria.", "B": "The patient is likely to have another immune impairment besides the one for which she was tested.", "C": "The patient should receive prophylactic courses of wide spectrum antibiotics to prevent infections.", "D": "The patient’s phagocytes can only perform extracellular killing.", "E": "The patient is susceptible to all mycotic infections."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old man comes to the physician with chronic abdominal pain. He has a 3-year history of severe peptic ulcer disease and esophagitis. Two months ago, he took omeprazole, clarithromycin, and amoxicillin for 14 days. His medical history is otherwise unremarkable. Currently, he takes omeprazole 60 mg/day. He is a 10 pack-year smoker and consumes alcohol regularly. Vital signs are within normal limits. Mild epigastric tenderness is noted on deep palpation of the epigastrium. Laboratory studies show:\nSerum\nCalcium 9.5 mg/dL\nPhosphorus 4 mg/dL\nAn upper endoscopy shows several large ulcers in the antrum and 2nd and 3rd parts of the duodenum. The rapid urease test is negative. Fasting gastrin levels are elevated. PET-CT with Ga-Dotatate shows a single mass in the wall of the duodenum. No other mass is detected. Pituitary MRI shows no abnormality. Which of the following is the most appropriate next step in management?", "answer": "Surgical resection", "options": {"A": "Adjuvant therapy with octreotide", "B": "Biological therapy with interferon-alpha", "C": "Quadruple therapy for Helicobacter pylori", "D": "Smoking cessation", "E": "Surgical resection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 16-day-old male newborn is brought to the emergency department because of fever and poor feeding for 2 days. He became very fussy the previous evening and cried for most of the night. He was born at 36 weeks' gestation and weighed 2430 g (5 lb 3 oz). The pregnancy and delivery were uncomplicated. The mother does not recall any sick contacts at home. He currently weighs 2776 g (6 lb 2 oz). He appears irritable. His temperature is 38.6°C (101.5°F), pulse is 180/min, and blood pressure is 82/51 mm Hg. Examination shows scleral icterus. He becomes more agitated when picked up. There is full range of motion of his neck and extremities. The anterior fontanelle feels soft and flat. Neurologic examination shows no abnormalities. Blood cultures are drawn and fluid resuscitation is initiated. A urinalysis obtained by catheterization shows no abnormalities. Which of the following is the most appropriate next step in diagnosis?", "answer": "Lumbar puncture", "options": {"A": "MRI of the head", "B": "Reassurance", "C": "Urine culture", "D": "CT scan of the head", "E": "Lumbar puncture"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old man comes to the emergency department because of left shoulder pain hours after suffering a fall from a height of approximately 10 feet while rock climbing about 5 hours ago. He initially thought the pain would resolve with rest but it became more severe over the last 2 hours. Last year while rock climbing he fell onto his right shoulder and “needed a sling to fix it”. He has psoriasis. His only medication is topical clobetasol. His pulse is 95/min, respiratory rate is 16/minute, and blood pressure is 114/70 mm Hg. Examination shows full passive and active range of motion at the left shoulder. There is no tenderness to palpation at the acromioclavicular joint. There are silvery plaques over both knees and elbows. Abdominal exam shows 7/10 left upper quadrant tenderness with voluntary guarding. A complete blood count and serum concentrations of electrolytes are within the reference range. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the abdomen", "options": {"A": "Serial vital signs for at least nine hours", "B": "CT scan of the abdomen", "C": "Abdominal ultrasound", "D": "Radiographs of the left shoulder", "E": "MRI of the left shoulder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3-year-old boy is brought to the emergency department because of persistent fever and cough. Three days ago, he was diagnosed with pneumonia and acute otitis media. He was started on ampicillin-sulbactam and clarithromycin, but his symptoms did not improve. The mother reports that her son has been hospitalized 3 times due to pneumonia. He was first diagnosed with pneumonia at the age of 10 months. She also reports several episodes of bilateral otitis media and recurrent respiratory tract infections. His immunizations are up-to-date. He is at the 50th percentile for height and 20th percentile for weight. He appears fatigued. His temperature is 38°C (100.4°F). Pneumatic otoscopy shows purulent otorrhea bilaterally. Pulmonary examination shows decreased breath sounds over both lung fields. The palatine tonsils and adenoids are hypoplastic. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Tyrosine kinase gene mutation", "options": {"A": "Defective NADPH oxidase", "B": "Defective IL-2R gamma chain", "C": "Defect in the ATM gene", "D": "WAS gene mutation", "E": "Tyrosine kinase gene mutation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 70-year-old woman is brought to her physician by her daughter who reports that the patient has been increasingly confused and forgetful over the past year. The daughter reports that the patient has difficulty finding words, remembering names, and maintaining a conversation. She has gotten lost twice while driving. Her past medical history is known for obesity, diabetes, and atrial fibrillation. She takes metformin, glyburide, and warfarin. She drinks socially and has a 30 pack-year smoking history. Her family history is notable for Parkinson’s disease in her father and stroke in her mother. A head CT demonstrates sulcal widening and narrowing of the gyri. The physician decides to start the patient on a medication known to inhibit a cell surface glutamate receptor. Which of the following is a downstream effect of this medication?", "answer": "Decreased intracellular calcium", "options": {"A": "Decreased intracellular calcium", "B": "Increased intracellular calcium", "C": "Increased intracellular sodium", "D": "Increased intracellular acetylcholine", "E": "Decreased intracellular acetylcholine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old farmer presents to the emergency department with a chief complaint of unusual behavior. His wife states that since this morning he has experienced dryness and flushing of his skin while working outside. As the day went on, the patient found it exceedingly difficult to urinate and had to create significant abdominal pressure for a weak stream of urine to be produced. Currently, the patient seems confused and responds incoherently. The patient has a past medical history of Parkinson's disease, alcohol abuse, irritable bowel syndrome, anxiety, diabetes mellitus, hypertension, constipation and a suicide attempt when he was 23 years old. He is currently taking lisinopril, hydrochlorothiazie, metformin, insulin, benztropine, levodopa/carbidopa, and vitamin C. The only other notable symptoms this patient has experienced are recent severe seasonal allergies. On physical exam you note dry, flushed skin, and a confused gentleman. His temperature is 99.5°F (37.5°C), pulse is 112/min, blood pressure is 130/90 mmHg, respirations are 18/min, and oxygen saturation is 96% on room air. Lab values are ordered. Which of the following is the most likely cause of this patient's presentation?", "answer": "Medication", "options": {"A": "Medication", "B": "Insecticide exposure", "C": "Alcohol", "D": "Infection", "E": "Heat stroke"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old man is brought to the emergency department by his wife because of progressive lethargy and confusion during the past 2 days. His wife reports that he has been complaining of nausea and increased urination for the past 5 days. He also developed a cough 1 week ago. He has a history of a cerebrovascular accident 3 years ago and was diagnosed with hypertension 10 years ago. Current medications include lisinopril and aspirin. His temperature is 38.5°C (101.3°F), pulse is 114/min, respirations are 15/min, and blood pressure is 108/75 mm Hg. He is somnolent and oriented only to person. Examination shows dry mucous membranes and decreased skin turgor. Crackles are heard at the left lung base. The remainder of the physical examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Blood glucose measurement", "options": {"A": "Chest x-ray", "B": "Serum calcium measurement", "C": "Broad-spectrum antibiotics", "D": "Blood glucose measurement", "E": "Arterial blood gas analysis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 59-year-old man comes to the emergency department because of progressively worsening chest pain and nausea that started while visiting a local bar 30 minutes ago. The pain radiates to the epigastric area. He has a 10-year history of untreated hypertension. He has smoked 1 pack of cigarettes daily for 35 years. The patient is diaphoretic and in marked distress. His pulse is 94/min, respirations are 28/min, and blood pressure is 161/92 mm Hg. Pulse oximetry on 2 L/min of oxygen via nasal cannula shows an oxygen saturation of 97%. Cardiac examination shows a regular heartbeat and a systolic ejection murmur heard best over the upper right sternal border. The lungs are clear to auscultation bilaterally. Pedal pulses are intact. An ECG shows inverted T waves in leads I, avL, and V5-6. Urine toxicology screening is positive for cocaine. Which of the following drugs is contraindicated in the management of this patient's condition?", "answer": "Propranolol", "options": {"A": "Propranolol", "B": "Diazepam", "C": "Prasugrel", "D": "Diltiazem", "E": "Aspirin\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old female presents with recent muscle weakness, fatigue, and constipation. Physical examination reveals a bradycardic patient with cool, dry skin. Which of the following lab values would be most likely to be present with this patient's presentation?", "answer": "Elevated serum CK", "options": {"A": "Elevated serum calcitonin", "B": "Elevated serum CK", "C": "Low serum TSH", "D": "Activating TSH-receptor immunoglobulins", "E": "Hypocalcemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old gravida 2 para 1 presents to her physician at 12 weeks gestation. She has no complaints. Her previous pregnancy 5 years ago had an uncomplicated course with vaginal delivery of a healthy boy at 39 + 1 weeks gestation. Her weight is 75 kg (165 lb) and the height is 168 cm (5 ft 6 in). On presentation, the blood pressure is 110/70 mm Hg, the heart rate is 83/min, the respiratory rate is 14/min, and the temperature is 36.6℃ (97.9℉). The physical examination is within normal limits. The gynecologic examination demonstrates a fetal heart rate of 180/min. The uterus cannot be palpated and the ultrasound exam is benign. Blood testing showed the following:\nRBC count 3.9 million/mm3\nLeukocyte count 11,100/mm3\nHb 11.6 g/dL\nHct 32%\nMCV 87 fl\nReticulocyte count 0.4%\nThe patient’s blood type is A neg. Which testing is indicated in this patient?", "answer": "Indirect Coombs test", "options": {"A": "Measurement of serum iron", "B": "Direct Coombs test", "C": "White blood cell differential", "D": "Indirect Coombs test", "E": "Measurement of serum vitamin B12"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old man presents to his primary care physician with frequent urination. He was recently hospitalized following a severe motorcycle accident in which he suffered multiple injuries to his head and extremities. He reports that he has been constantly thirsty and has been urinating four to five times per night since being discharged from the hospital one week prior to presentation. His past medical history is notable for type II diabetes mellitus, which is well controlled on metformin. He has a 10 pack-year smoking history and drinks 3-4 alcoholic beverages per day. His temperature is 98.8°F (37.1°C), blood pressure is 110/70 mmHg, pulse is 95/min, and respirations are 18/min. Physical examination reveals delayed capillary refill and decreased skin turgor. Notable laboratory results are shown below:\n\nSerum:\nNa+: 148 mEq/L\nCl-: 101 mEq/L\nK+: 3.7 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 110 mg/dL\nHemoglobin A1c: 5.7%\n\nThis patient’s condition is most likely caused by defective production in which of the following locations?", "answer": "Supraoptic nucleus of the hypothalamus", "options": {"A": "Supraoptic nucleus of the hypothalamus", "B": "Lateral nucleus of the hypothalamus", "C": "Posterior pituitary", "D": "Anterior pituitary", "E": "Posterior nucleus of the hypothalamus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 88-year-old man presents to his primary care physician due to insomnia. The patient’s wife states that she often sees him sitting awake at night, seemed visibly irritated. This has persisted for years but worsened recently when the patient attended a funeral for one of his friends in the military. The patient states that he has trouble sleeping and finds that any slight sound causes him to feel very alarmed. Recently, the patient has been having what he describes as strong memories of events that occurred with his fellow soldiers while at war. At times he awakes in a cold sweat and has not been able to get quality sleep in weeks. The patient has a past medical history of anxiety, obesity, and type II diabetes mellitus. His current medications include insulin, metformin, lisinopril, sodium docusate, and fish oil. Which of the following is the best initial medical therapy for this patient?", "answer": "Escitalopram", "options": {"A": "Bupropion", "B": "Buspirone", "C": "Clonazepam", "D": "Escitalopram", "E": "Trazodone"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 66-year-old man presents to the office complaining of abdominal pain. He reports that the pain is mid-epigastric and “gnawing.” It worsens after meals but improves “somewhat” with antacids. The patient’s medical history is significant for hypertension, hyperlipidemia, and gout. He takes aspirin, lisinopril, atorvastatin, and allopurinol. He uses ibuprofen during acute gout attacks and takes over the counter multivitamins. He also started drinking ginkgo tea once a week after his wife saw a news story on its potential benefits. The patient has a glass of whiskey after work 2 nights a week but denies tobacco or illicit drug use. An upper endoscopy is performed that reveals a gastric ulcer. A urease breath test is positive for Heliobacter pylori. The patient is prescribed bismuth subsalicylate, omeprazole, metronidazole, and tetracycline for 2 weeks. At follow-up, the patient continues to complain of abdominal pain. He has taken all his medications as prescribed along with 10-12 tablets of antacids a day. He denies hematemesis, hematochezia, or melena. Biopsy from the previous upper endoscopy was negative for malignancy. A repeat urease breath test is positive. Which of the following is the most likely cause for the patient’s poor treatment response?", "answer": "Antacid use", "options": {"A": "Alcohol use", "B": "Allopurinol", "C": "Antacid use", "D": "Ginkgo tea", "E": "Ibuprofen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old boy is brought to the emergency department by his brother after losing consciousness 1 hour ago. The brother reports that the patient was skateboarding outside when he fell on the ground and started to have generalized contractions. There was also some blood coming from his mouth. The contractions stopped after about 1 minute, but he remained unconscious for a few minutes afterward. He has never had a similar episode before. There is no personal or family history of serious illness. He does not smoke or drink alcohol. He does not use illicit drugs. He takes no medications. On arrival, he is confused and oriented only to person and place. He cannot recall what happened and reports diffuse muscle ache, headache, and fatigue. He appears pale. His temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 130/80 mm Hg. There is a small wound on the left side of the tongue. A complete blood count and serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference ranges. Toxicology screening is negative. An ECG shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the head", "options": {"A": "Lorazepam therapy", "B": "Reassurance and follow-up", "C": "Lumbar puncture", "D": "CT scan of the head", "E": "Electroencephalography\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 59-year-old man comes to the physician because of urinary frequency and perineal pain for the past 3 days. During this time, he has also had pain with defecation. He is sexually active with his wife only. His temperature is 39.1°C (102.3°F). His penis and scrotum appear normal. Digital rectal examination shows a swollen, exquisitely tender prostate. His leukocyte count is 13,400/mm3. A urine culture obtained prior to initiating treatment is most likely to show which of the following?", "answer": "Gram-negative, lactose-fermenting rods in pink colonies", "options": {"A": "Gram-negative, lactose-fermenting rods in pink colonies", "B": "Gram-negative, oxidase-positive rods in green colonies", "C": "Gram-negative, encapsulated rods in mucoid colonies", "D": "Weakly staining, obligate intracellular bacilli", "E": "Gram-negative, aerobic, intracellular diplococci"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman is brought to the emergency department for the evaluation of burn injuries that she sustained after stumbling into a bonfire 1 hour ago. The patient has severe pain in her left leg and torso, and minimal pain in her right arm. She does not smoke cigarettes. She takes no medications. She is tearful and in moderate distress. Her temperature is 37.2°C (99.0°F), pulse is 88/min, respirations are 19/min, and blood pressure is 118/65 mm Hg. Her pulse oximetry is 98% on room air. Cardiopulmonary examination shows no abnormalities. There are two tender, blanchable erythemas without blisters over a 5 x 6 -cm area of the left abdomen and a 3 x 2-cm area of the left anterior thigh. There is also an area of white, leathery skin and tissue necrosis encircling the right upper extremity just proximal to the elbow, which is dry and nontender. An ECG shows normal sinus rhythm with no ST or T wave changes. She is started on intravenous fluids. Which of the following is the most appropriate next step in management?", "answer": "Monitoring of peripheral pulses and capillary filling", "options": {"A": "Serial arterial blood gas analysis", "B": "Soft-tissue ultrasound", "C": "Intravenous ampicillin therapy", "D": "Monitoring of peripheral pulses and capillary filling", "E": "X-ray of the chest"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year-old boy is brought to the emergency department after falling from a trampoline and landing on his left arm. On presentation, he is found to be holding his left arm against his chest and says that his arm is extremely painful just above the elbow. Radiographs are obtained showing the finding in figure A. The boy's arm is reduced and placed into a splint pending surgical fixation. If this patient's fracture is associated with a nerve injury, which of the following actions would he most likely be unable to perform in the emergency department?", "answer": "Thumb flexion", "options": {"A": "Elbow flexion", "B": "Finger crossing", "C": "Finger extension", "D": "Shoulder abduction", "E": "Thumb flexion"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 30-year-old woman came to her OBGYN for an infertility consultation. The patient reports having intercourse with her husband at least 3 times per week with increasing frequency during the periods. The lab reports of her husband revealed an adequate sperm count. After the work-ups was complete, her OBGYN prescribed a medication similar to GnRH to be administered in a pulsatile manner. Which drug is prescribed to the patient?", "answer": "Leuprolide", "options": {"A": "Danazol", "B": "Leuprolide", "C": "Anastrazole", "D": "Clomiphene", "E": "Mestranol"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old man presents to his primary care provider for recurrent epigastric pain. He reports a 3-month history of gnawing epigastric and chest pain that is worse after meals and after lying down. His past medical history is notable for obesity, hypertension, and hyperlipidemia. He takes lisinopril and rosuvastatin. He has a 30 pack-year smoking history and drinks 4-5 beers per day. On exam, he is well-appearing and in no acute distress. He has no epigastric tenderness. He is prescribed an appropriate medication for his symptoms and is told to follow up in 2 weeks. He returns 2 weeks later with improvement in his symptoms, and a decision is made to continue the medication. However, he returns to clinic 3 months later complaining of decreased libido and enlarged breast tissue. Which of the following medications was this patient most likely taking?", "answer": "Cimetidine", "options": {"A": "Cimetidine", "B": "Famotidine", "C": "Lansoprazole", "D": "Nizatidine", "E": "Calcium carbonate"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 22-year-old Caucasian G1 presents to her physician at 29 weeks gestation for a checkup. The  medical history is unremarkable and the current pregnancy has been uncomplicated. Her weight is 81 kg (178.6 lb) and the height is 169 cm (5 ft 6 in). She has gained 13 kg (28.6 lb) during the pregnancy. She has no abnormalities on physical examination. Which of the following screening tests should be obtained ?", "answer": "Non-fasting oral glucose tolerance test with 50 g of glucose", "options": {"A": "Fasting glucose level", "B": "Non-fasting oral glucose tolerance test with 50 g of glucose", "C": "Fasting oral glucose test with 50 g of glucose", "D": "Non-fasting oral glucose load test with 75 g of glucose", "E": "Measurement of HbA1c"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man is brought to the emergency department 30 minutes after falling off a staircase and hitting his head on the handrail. He was unconscious for 10 minutes and vomited twice. On arrival, he is drowsy. Examination shows a fixed, dilated left pupil and right-sided flaccid paralysis. A CT scan of the head shows a skull fracture in the region of the pterion and a biconvex hyperdensity overlying the left frontotemporal lobe. This patient's condition is most likely caused by damage to a vessel that enters the skull through which of the following foramina?", "answer": "Foramen spinosum", "options": {"A": "Foramen lacerum", "B": "Jugular foramen", "C": "Foramen rotundum", "D": "Foramen magnum", "E": "Foramen spinosum"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 5-day-old male newborn is brought to the physician by his mother for the evaluation of progressive yellowing of his skin for 2 days. The mother reports that the yellowing started on the face and on the forehead before affecting the trunk and the limbs. She states that she breastfeeds every 2–3 hours and that the newborn feeds well. He has not vomited and there have been no changes in his bowel habits or urination. The patient was born at 38 weeks' gestation via vaginal delivery and has been healthy. His newborn screening was normal. His vital signs are within normal limits. Physical examination shows scleral icterus and widespread jaundice. The remainder of the examination shows no abnormalities. Serum studies show:\nBilirubin\nTotal 8 mg/dL\nDirect 0.5 mg/dL\nAST 16 U/L\nALT 16 U/L\nWhich of the following is the most appropriate next step in management?\"", "answer": "Reassurance", "options": {"A": "Phototherapy", "B": "Exchange transfusion", "C": "Abdominal sonography", "D": "Intravenous immunoglobulin", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A previously healthy 32-year-old man is brought to the emergency department by his girlfriend after having a seizure. Earlier that day, he also experienced a nosebleed that took 30 minutes to stop when applying pressure. He has had no sick contacts or history of epilepsy or other seizure disorder. He does not take any medications. His temperature is 39.1 °C (102.4 °F), pulse is 106/min, respirations are 26/min, and blood pressure is 128/70 mm Hg. He is confused and disoriented. Examination shows pallor and scattered petechiae over the trunk and arms. The neck is supple, and neurological examination is otherwise within normal limits. Laboratory studies show:\nHemoglobin 9 g/dL\nLeukocyte count 8,200/mm3\nPlatelet count 34,000/mm3\nProthrombin time 13 seconds\nPartial thromboplastin time 30 seconds\nFibrin split products negative\nSerum\nCreatinine 2.9 mg/dL\nBilirubin\nTotal 3.2 mg/dL\nDirect 0.4 mg/dL\nLactate dehydrogenase 559 U/L\nA peripheral blood smear shows numerous schistocytes. Which of the following is the most appropriate next step in management?\"", "answer": "Plasma exchange therapy", "options": {"A": "Transfusion of packed red blood cells", "B": "Plasma exchange therapy", "C": "Fresh frozen plasma transfusion", "D": "Platelet transfusion", "E": "Intravenous tranexamic acid\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old girl is brought to the physician because of a nonpruritic, painless rash that has been on her face for 5 days. She was born at term and has been healthy throughout childhood. Her 62-year-old maternal grandmother has bullous pemphigoid. Her development is adequate for her age and immunizations are up-to-date. She appears healthy and well-nourished. Her temperature is 37.0°C (98.6°F) pulse is 90/min, and respiratory rate is 18/min. Examination shows a crusted rash on the right side of the patient's face. An image of the patient's lower face is shown. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Topical mupirocin therapy", "options": {"A": "Oral acyclovir therapy", "B": "Oral cephalexin therapy", "C": "Oral clindamycin therapy", "D": "Topical miconazole therapy", "E": "Topical mupirocin therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old female medical student presents to the emergency department after she develops sudden difficulty breathing and vague chest pain while preparing for exams. The chest pain is non-pleuritic without radiation. She denies any recent travel. She denies any hemoptysis, nausea, vomiting, or leg pain. She only takes oral contraceptives; she denies smoking or alcohol use. Her vitals reveal a heart rate of 120 beats per minute, blood pressure of 100/80 mm Hg, and respiratory rate of 30 per minute. She is afebrile. Otherwise, her physical exam is unremarkable. A CT scan of her chest with IV contrast reveals filling defects along her left pulmonary artery. Which of the following is the most likely mechanism of this finding?", "answer": "Hypercoagulability", "options": {"A": "Venous stasis", "B": "Endothelial injury", "C": "Dehydration", "D": "Hypercoagulability", "E": "Anxiety"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 1-year-old immigrant girl has not received any recommended vaccines since birth. She attends daycare and remains healthy despite her daily association with several other children for the past 3 months at a home day-care facility. Which of the following phenomena explains why she has not contracted any vaccine-preventable diseases such as measles, diphtheria, or pertussis?", "answer": "Herd immunity", "options": {"A": "Genetic drift", "B": "Genetic shift", "C": "Tolerance", "D": "Immune evasion", "E": "Herd immunity"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old woman presents to her physician with a decreased interest in her daily activities. She says that she has noticed a decreased motivation to participate in her daily routine.  She says she feels sad and depressed on most days of the week. She reports her symptoms have been there for about two months but have been more severe for the past 3 weeks. She also says she is unable to sleep well at night and feels tired most of the day, which is affecting her job performance. The patient reports a 10-pack-year smoking history which has increased in frequency lately and she would like to quit. Lately, she has observed an inability to reach orgasm during intercourse and has also lost all interest in sex. Which of the following is the most appropriate pharmacotherapy for this patient?", "answer": "Bupropion", "options": {"A": "Venlafaxine", "B": "Mirtazapine", "C": "Bupropion", "D": "Fluoxetine", "E": "Trazodone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Two 19-year-old men are referred by their professor and mentor to a psychiatrist for substance abuse management. The two friends have both used different stimulants for 3 years—Drug A and Drug B, respectively. Both use these substances cyclically. Use of Drug A usually lasts for about 12 hours. The cycle for Drug B lasts several days. A month ago, both men visited the emergency room (ER) due to acute intoxication. Clinical features in the emergency department included hypotension, bradycardia, sweating, chills, mydriasis, nausea, and psychomotor agitation. After a urine drug screen, the psychiatrist identifies both the drugs and informs the professor that although both Drug A and Drug B are stimulants, their mechanisms of action are different. Drug A is an alkaloid that is naturally present in the leaves of the coca plant, while it is possible to make Drug B from over-the-counter nasal decongestant products. Which of the following options best describes the mechanism of action of both drugs?", "answer": "Drug A predominantly acts by inhibiting the reuptake of monoamine neurotransmitters (dopamine, serotonin, and norepinephrine) at the synapse, while Drug B does not.", "options": {"A": "Drug A transiently increases the extracellular concentration of dopamine in the reward circuit, while Drug B does not.", "B": "Drug A predominantly acts by inhibiting the reuptake of monoamine neurotransmitters (dopamine, serotonin, and norepinephrine) at the synapse, while Drug B does not.", "C": "Drug A predominantly acts by increasing the release of monoamine neurotransmitters (dopamine, serotonin, and norepinephrine) into the synapse, while Drug B does not.", "D": "Drug A increases serotonin activity, while Drug B does not.", "E": "Drug A increases norepinephrine activity, while Drug B does not."}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old woman presents to the clinic for a routine examination. She has a chronic history of systemic lupus erythematosus, diagnosed at age 27. Medications include hydroxychloroquine and low-dose prednisone. She has had no recent flare-ups and is compliant with her medication. Anticardiolipin and anti-beta-2 glycoprotein-1 antibodies are negative, and she has had no history of thrombi or emboli. Physical examination is normal except for mild bilateral tenderness and swelling of the knees. Creatinine and GFR are normal. Which of the following is the next best step in management to monitor disease activity?", "answer": "Anti-dsDNA antibody levels", "options": {"A": "Urinalysis and renal biopsy", "B": "Anti-dsDNA antibody levels", "C": "Anti-Smith antibody levels", "D": "Reduce dosage and taper off hydroxychloroquine", "E": "Arthrocentesis and synovial fluid analysis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-year-old boy is brought to a pediatrician by his mother for evaluation of fever, malaise, and rash with severe itching all over his body for the past 5 days. His immunization history is unavailable. His vital signs include: pulse 110/min, temperature 37.8°C (100.0°F), and respiratory rate 26/min. On examination of the skin, diffuse peeling vesicular lesions involving the arms and chest are observed. The pediatrician diagnosis the boy with chickenpox and reassures the mother. A few days later the boy returns to the clinic for a follow-up with his mother. The skin lesions have healed and there are scars. The formation of these scars is best described by which of the following statements?", "answer": "It is a part of the healing process of acute inflammation.", "options": {"A": "The scars represent complete resolution of acute inflammation.", "B": "It is a part of the healing process of acute inflammation.", "C": "The scars are permanent and remain for life in all cases.", "D": "Neutrophils, plasma cells, and macrophages are the predominant cells in these lesions.", "E": "The lesions now have progressed on to chronic inflammation."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old girl is brought to her pediatrician's office complaining of frequent diarrhea, fatigue, and inability to gain weight. Her vital signs are within normal limits, and her BMI is 17. She describes her stools as pale, malodorous, and bulky. She often has abdominal bloating. Her symptoms are most prominent after breakfast when she typically consumes cereal. After several weeks of careful evaluation and symptomatic treatment, the pediatrician recommends an esophagogastroduodenoscopy. A diagnostic biopsy shows blunting of intestinal villi and flat mucosa with multiple intraepithelial lymphocytes. Which of the following is the patient likely deficient in?", "answer": "IgA", "options": {"A": "IgA", "B": "IgM", "C": "IgG", "D": "IgE", "E": "IgD"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 23-year-old man is brought to the emergency department by a coworker for an injury sustained at work. He works in construction and accidentally shot himself in the chest with a nail gun. Physical examination shows a bleeding wound in the left hemithorax at the level of the 4th intercostal space at the midclavicular line. Which of the following structures is most likely injured in this patient?", "answer": "Left upper lobe of the lung", "options": {"A": "Right atrium of the heart", "B": "Superior vena cava", "C": "Inferior vena cava", "D": "Left atrium of the heart", "E": "Left upper lobe of the lung"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old woman presents to her primary care physician due to amenorrhea. The patient states that historically she has her period once every three months but recently has not had it at all. Otherwise, she has no other complaints. The patient recently started college and is a varsity athlete for the track team. She works part time in a coffee shop and is doing well in school. The patient is not sexually active and does not drink alcohol, use illicit drugs, or smoke. She has no significant past medical history and occasionally takes ibuprofen for headaches. Her temperature is 99.5°F (37.5°C), blood pressure is 100/55 mmHg, pulse is 50/min, respirations are 10/min, and oxygen saturation is 98% on room air. On physical exam, you note a young, lean, muscular woman in no acute distress. Which of the following is the most likely long-term outcome in this patient?", "answer": "Osteoporosis", "options": {"A": "Endometrial cancer", "B": "Infertility", "C": "Osteoarthritis", "D": "Osteoporosis", "E": "Anorexia nervosa"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old man who was previously antisocial, low energy at work, and not keen to attend office parties was arrested and brought to the emergency department after he showed up to the office Christmas party out of control. He was noted to be very energetic and irritable. He spent the entire evening hijacking conversations and sharing his plans for the company that will save it from inevitable ruin. What other finding are you most likely to find in this patient’s current condition?", "answer": "Irresponsibility", "options": {"A": "Irresponsibility", "B": "Hypersomnia after days of not sleeping", "C": "Patient completing numerous outstanding projects", "D": "Rapid but interruptible speech pattern", "E": "Patient is unlikely to have a major depressive episode"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 70-year-old man is at his dermatologist’s office for the treatment of a severely pruritic erythroderma with scaling on his buttocks that has been slowly progressing over the past two weeks. The patient works as a truck driver and has a history of hypertension treated with enalapril. The patient reports having tried an over-the-counter cream on the rash without improvement. The vital signs are within normal range. On physical exam, he has multiple confluent and well-demarcated pink patches on his buttocks and legs with some scaling and enlarged inguinal lymph nodes. The dermatologist orders a skin biopsy that reveals Pautrier microabscesses. What is the most likely diagnosis?", "answer": "Mycosis fungoides", "options": {"A": "Psoriasis", "B": "Linchen planus", "C": "Atopic dermatitis", "D": "Mycosis fungoides", "E": "Kaposi sarcoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old G6P6 woman with a history of fibroids gives birth to twins via vaginal delivery. Her pregnancy was uneventful, and she reported having good prenatal care. Both placentas are delivered immediately after the birth. The patient continues to bleed significantly over the next 20 minutes. Her temperature is 97.0°F (36.1°C), blood pressure is 124/84 mmHg, pulse is 95/min, respirations are 16/min, and oxygen saturation is 98% on room air. Continued vaginal bleeding is noted. Which of the following is the most appropriate initial step in management?", "answer": "Bimanual massage", "options": {"A": "Bimanual massage", "B": "Blood product transfusion", "C": "Hysterectomy", "D": "Oxytocin", "E": "Uterine artery embolization"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 13-year-old boy is brought to the pediatrician by his parents who are concerned about his short stature. He also has had recurrent episodes of diarrhea. Past medical history is significant for iron deficiency anemia diagnosed 6 months ago. Physical examination is unremarkable except that he is in the 9th percentile for height. Serum anti-tissue transglutaminase (anti-tTG) antibodies are positive. An upper endoscopy along with small bowel luminal biopsy is performed. Which of the following histopathologic changes would most likely be present in the mucosa of the duodenal biopsy in this patient?", "answer": "Blunting of the intestinal villi", "options": {"A": "Neutrophilic infiltration", "B": "Blunting of the intestinal villi", "C": "Granulomas extending through the layers of the intestinal wall", "D": "Crypt aplasia", "E": "Cuboidal appearance of basal epithelial cells"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 11-year-old girl is brought into the clinic by her parents, who are distraught over her behavior. They state that over the past several months she has started to act oddly, combing the hair of her toy dolls for hours without stopping and repetitively counting her steps in the house. She is often brought to tears when confronted about these behaviors. The patient has no past medical history. When questioned about family history, the mother states she has needed close medical follow-up in the past, but declines to elaborate. The patient's vital signs are all within normal limits. On physical exam the patient is a well nourished 11-year-old girl in no acute distress. She has occasional motor tics, but the remainder of the exam is benign. What is the diagnosis in this patient?", "answer": "Obsessive compulsive disorder (OCD)", "options": {"A": "Autism spectrum disorder (ASD)", "B": "Generalized anxiety disorder (GAD)", "C": "Obsessive compulsive disorder (OCD)", "D": "Tourette's syndrome", "E": "Major depressive disorder (MDD)"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old man accountant is admitted to the emergency department with complaints of retrosternal crushing pain that radiates to his left arm and jaw. The medical history is significant for hyperlipidemia and arterial hypertension, for which he is prescribed a statin and ACE inhibitor, respectively. An ECG is obtained and shows an ST-segment elevation in leads avF and V2-V4. The blood pressure is 100/50 mm Hg, the pulse is 120/min, and the respiratory rate is 20/min. His BMI is 33 kg/m2 and he has a 20-year history of smoking cigarettes. Troponin I is elevated. The patient undergoes percutaneous coronary intervention immediately after admission. Angioplasty and stenting were successfully performed. On follow-up the next day, the ECG shows decreased left ventricular function and local hypokinesia. The patient is re-evaluated 14 days later. The echocardiography reveals a normal ejection fraction and no hypokinesis. Which of the phenomena below explains the patient’s clinical course?", "answer": "Myocardial stunning", "options": {"A": "Coronary steal syndrome", "B": "Reperfusion injury", "C": "Myocardial hibernation", "D": "Myocardial stunning", "E": "Coronary collateral circulation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman, primigravida, gave birth to a boy 3 months ago and now presents the newborn to your clinic for evaluation. She did not receive prenatal care. She reports that she was taking a medication for her mood swings, but cannot remember the medication’s name. The baby was born cyanotic, with a congenital malformation of the heart that is characterized by apical displacement of the septa and posterior tricuspid valve leaflets. A chest radiograph is shown in the image. Which of the following medications was the mother most likely taking?", "answer": "Lithium", "options": {"A": "Buspirone", "B": "Clozapine", "C": "Losartan", "D": "Lithium", "E": "Enalapril"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is studying gene expression in a mouse model. She inactivates the assembly of small nuclear ribonucleoproteins (snRNPs) in motor nerve cells. Which of the following processes is most likely to be affected as a result?", "answer": "Removal of introns", "options": {"A": "Folding of proteins", "B": "Aminoacylation of tRNA", "C": "Activity of 3′ to 5′ proofreading", "D": "Unwinding of DNA strands", "E": "Removal of introns"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman comes to the physician for evaluation of a mass in the left breast that she first noticed 2 weeks ago. During this period, the mass has not increased in size and the patient has had no pain. Three months ago, she hit her left chest against the closet door, which was painful for a day. Menses occurs at regular 28-day intervals and last for 5 days with moderate flow. Her last menstrual period was 3 weeks ago. Physical examination shows dense breasts and a 2.5-cm well-defined, rubbery, mobile mass that is nontender in the upper outer quadrant of the left breast. There is no axillary adenopathy. Which of the following is the most likely diagnosis?", "answer": "Fibroadenoma", "options": {"A": "Phyllodes tumor", "B": "Fibrocystic changes of the breast", "C": "Fibroadenoma", "D": "Lobular carcinoma", "E": "Fat necrosis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70 year-old man comes to the physician for difficulty swallowing for 6 months. During this time, he has occasionally coughed up undigested food. He did not have weight loss or fever. Four weeks ago, he had an episode of sore throat, that resolved spontaneously. He has smoked one pack of cigarettes daily for 5 years. He has gastroesophageal reflux disease and osteoporosis. Current medications include alendronate and omeprazole. His temperature is 37.0°C (98.6°F), pulse is 84/min, and blood pressure is 130/90 mmHg. On examination, he has foul-smelling breath and a fluctuant mass on the right neck. Which of the following is most likely involved in the pathogenesis of this patient's symptoms?", "answer": "Abnormal esophageal motor function", "options": {"A": "Deep neck space infection", "B": "Degeneration of neurons in the esophageal wall", "C": "Cellular dysplasia", "D": "Abnormal esophageal motor function", "E": "Adverse effect of medication\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A bacterial isolate obtained from a hospitalized patient is found to be resistant to amikacin. The isolated bacteria most likely has which of the following characteristics?", "answer": "Enhanced ability to transfer acetyl groups", "options": {"A": "D-Ala to D-Lac mutation", "B": "DNA topoisomerase II mutation", "C": "Low-affinity penicillin binding protein", "D": "Increased drug influx capacity", "E": "Enhanced ability to transfer acetyl groups"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 10-year-old boy is brought to the pediatrician by his parents with complaints of short stature with small hands and skin hypopigmentation. A detailed development history reveals that he was born by normal vaginal delivery at full term and his neonatal period was uneventful. Until he was 6 months of age, he was breast-fed and then solid foods were started. At the age of 3 years, his parents noted that he had difficulty in sucking and swallowing. They also noted a weak cry. His motor milestones were delayed. His intelligence quotient (IQ) is 65. His temperature is 37.0ºC (98.6°F), pulse is 88/min, and respirations are 20/min. He has a short stature and falls in the obese category according to his body mass index. His neurologic examination shows the presence of hypotonia. Panoramic radiographic examination shows anterior teeth crowding and the presence of residual roots in some teeth. Which of the following is the most likely cause of this condition?", "answer": "Paternal inheritance", "options": {"A": "Maternal inheritance", "B": "Paternal inheritance", "C": "Both paternal inheritance and maternal inheritance", "D": "Infectious in origin", "E": "Nutritional and metabolic in origin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old woman is brought to the physician for worsening depressive mood and irritability. Her mood changes began several months ago. Her husband has also noticed shaky movements of her limbs and trunk for the past year. The patient has no suicidal ideation. She has no history of serious illness and takes no medications. Her father died by suicide at the age of 45 years. Her temperature is 37°C (98.6°F), pulse is 76/min, and blood pressure is 128/72 mm Hg. She speaks slowly and quietly and only looks at the floor. She registers 3/3 words but can recall only one word 5 minutes later. Examination shows irregular movements of the arms and legs at rest. Extraocular eye movements are normal. Muscle strength is 5/5 throughout, and deep tendon reflexes are 2+ bilaterally. Further evaluation is most likely to show which of the following?", "answer": "Caudate nucleus atrophy on MRI", "options": {"A": "Mitral vegetations on echocardiogram", "B": "Positive Babinski sign on physical examination", "C": "Oligoclonal bands on lumbar puncture", "D": "Poor performance on an IQ test", "E": "Caudate nucleus atrophy on MRI"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old man presents to his primary care physician for a regular check-up. The patient was born in Germany in 1960 in with shortened limbs, underdeveloped digits, absent external ears, and a cleft palate. He is currently in a wheelchair. His past medical history is also notable for hypertension and allergies. He takes lisinopril daily and loratadine as needed. His mother had a complicated past medical history and took multiple medications during her pregnancy. His temperature is 98.6°F (37°C), blood pressure is 120/80 mmHg, pulse is 90/min, and respirations are 20/min. The drug that most likely caused this patient's condition is also indicated for which of the following?", "answer": "Multiple myeloma", "options": {"A": "Acne vulgaris", "B": "Deep venous thrombosis", "C": "Multiple myeloma", "D": "Bipolar disease", "E": "Recurrent miscarriage"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 29-year-old woman presents to her gynecologist because of chronic pelvic pain that she has been experiencing for the last 6 months. Specifically, she says that she has severe pain during menstruation that is localized primarily to her lower abdomen and pelvis. In addition, she has been having pain while defecating and during intercourse. She has no past surgical history and her past medical history is significant for asthma. She uses protection while having intercourse with her long time boyfriend and has never been pregnant. Physical exam reveals adnexal tenderness and the presence of an adnexal mass. Laparoscopic examination is conducted showing several cysts filled with dark brown fluid on her ovaries and powder burn marks along her peritoneal surfaces. Which of the following markers would most likely be elevated in this patient?", "answer": "CA-125", "options": {"A": "Alpha-fetoprotein", "B": "Beta-hCG", "C": "Bombesin", "D": "CA-125", "E": "CA-19-9"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 70-year-old man presented to the emergency department complaining of left-sided weakness for the past 5 hours. Past medical history is significant for a previous ischemic stroke involving the right posterior cerebral artery and left-sided homonymous hemianopia. He also has a history of type-II diabetes mellitus and hypertension. He takes an 81 mg aspirin, amlodipine, atorvastatin, and a vitamin supplement with calcium and vitamin D. A brain MRI reveals a small atrophic area of the left occipital lobe and a new acute infarct involving the territory of the right middle cerebral artery. Electrocardiogram (ECG) shows normal sinus rhythm. An echocardiogram reveals mild left ventricular hypertrophy with an ejection fraction of 55%. Doppler ultrasound of the carotid arteries reveals no significant narrowing. What is the next step in the management to prevent future risks of stroke?", "answer": "Add dipyridamole", "options": {"A": "Add dipyridamole", "B": "Add warfarin", "C": "Increase aspirin to 325 mg", "D": "Administer tPA", "E": "Stop aspirin and start warfarin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old primigravid woman comes to the physician for a prenatal visit at 37-weeks' gestation because of worsening back pain for 3 weeks. The pain is worse with extended periods of walking, standing, and sitting. She has not had any changes in bowel movements or urination. Her mother has rheumatoid arthritis. Examination of the back shows bilateral pain along the sacroiliac joint area as a posterior force is applied through the femurs while the knees are flexed. She has difficulty actively raising either leg while the knee is extended. Motor and sensory function are normal bilaterally. Deep tendon reflexes are 2+. Babinski sign is absent. Pelvic examination shows a uterus consistent in size with a 37-weeks' gestation. There is no tenderness during abdominal palpation. Which of the following is the most likely explanation for this patient's symptoms?", "answer": "Relaxation of the pelvic girdle ligaments", "options": {"A": "Spinal cord compression", "B": "Vertebral bone compression fracture", "C": "Placental abruption", "D": "Relaxation of the pelvic girdle ligaments", "E": "Rheumatoid arthritis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator studying immune response administers a 0.5 mL intradermal injection of an autoclaved microorganism to a study volunteer. Four weeks later, there is a 12-mm, indurated, hypopigmented patch over the site of injection. Which of the following is the most likely explanation for the observed skin finding?", "answer": "Increased activity of CD4+ Th1 cells", "options": {"A": "Increased lipid uptake by macrophages", "B": "Increased antibody production by B cells", "C": "Increased activity of neutrophils", "D": "Increased activity of CD4+ Th1 cells", "E": "Increased release of transforming growth factor beta"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old woman comes to the physician because of oligomenorrhea and intermittent vaginal spotting for 5 months. Menses previously occurred at regular 28-day intervals and lasted for 5 days with normal flow. She has also noted increased hair growth on her chin. She is not sexually active. She takes no medications. Physical examination shows temporal hair recession and nodulocystic acne on her cheeks and forehead. There is coarse hair on the chin and the upper lip. Pelvic examination shows clitoral enlargement and a right adnexal mass. Laboratory studies show increased serum testosterone concentration; serum concentrations of androstenedione and dehydroepiandrosterone are within the reference ranges. Ultrasonography of the pelvis shows a 10-cm right ovarian tumor. Which of the following is the most likely diagnosis?", "answer": "Sertoli-Leydig cell tumor", "options": {"A": "Ovarian thecoma", "B": "Dermoid cyst", "C": "Ovarian dysgerminoma", "D": "Serous cystadenoma", "E": "Sertoli-Leydig cell tumor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 9-year-old girl presents to the emergency department with a fever and a change in her behavior. She presented with similar symptoms 6 weeks ago and was treated for an Escherchia coli infection. She also was treated for a urinary tract infection 10 weeks ago. Her mother says that last night her daughter felt ill and her condition has been worsening. Her daughter experienced a severe headache and had a stiff neck. This morning she was minimally responsive, vomited several times, and produced a small amount of dark cloudy urine. The patient was born at 39 weeks and met all her developmental milestones. She is currently up to date on her vaccinations. Her temperature is 99.5°F (37.5°C), blood pressure is 60/35 mmHg, pulse is 190/min, respirations are 33/min, and oxygen saturation is 98% on room air. The patient is started on intravenous fluids, vasopressors, and broad-spectrum antibiotics. Which of the following is the best underlying explanation for this patient's presentation?", "answer": "Intentional contamination", "options": {"A": "Gastroenteritis", "B": "Intentional contamination", "C": "Meningitis", "D": "Sepsis", "E": "Urinary tract infection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old woman comes to your office with a variety of complaints. As part of her evaluation, she undergoes laboratory testing which reveals the presence of anti-centromere antibodies. All of the following symptoms and signs would be expected to be present EXCEPT:", "answer": "Hypercoagulable state", "options": {"A": "Pallor, cyanosis, and erythema of the hands", "B": "Calcium deposits on digits", "C": "Blanching vascular abnormalities", "D": "Hypercoagulable state", "E": "Heartburn and regurgitation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 46-year-old woman comes to the physician for a 6-month history of worsening bronchial asthma control. Before this issue began, she only used her salbutamol inhaler once a day. Now, she has to use it multiple times daily and also reports frequent nighttime awakening. Seven months ago, she moved to an apartment that is damp and has mold on some of the walls. The physician injects 0.1 mL of Candida albicans extract on the mid-volar surface of the right arm intradermally. After 48 hours there is a palpable induration of 17 mm. This reaction is most likely a result of release of which of the following substances?", "answer": "Interferon-γ", "options": {"A": "Tryptase", "B": "Interleukin-10", "C": "Lysozyme", "D": "Interferon-γ", "E": "Superoxide anion\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old, G1P0 woman at 35 weeks of gestation comes to the emergency room for a severe headache. She reports that she was washing the dishes 2 hours ago when a dull headache came on and progressively worsened. She also reports 2 episodes of intermittent blurred vision over the past hour that has since cleared. Nothing similar has ever happened before. She denies any precipitating events, trauma, mental status changes, abdominal pain, lightheadedness, fever, ulcers, or urinary changes. Her temperature is 98.9°F (37.1°C), blood pressure is 160/110 mmHg, pulse is 98/min, respirations are 12/min, and oxygen saturation is 98%. A physical examination demonstrates a rash on her face that she attributes to a recent change in cosmetics. A urine test demonstrates the presence of protein. What is the most likely explanation for this patient’s symptoms?", "answer": "Abnormal placental spiral arteries", "options": {"A": "Abnormal placental spiral arteries", "B": "Neoplasm of meningeal tissue", "C": "Premature separation of the placenta from the uterine wall", "D": "Production of pathogenic autoantibodies and tissue injury", "E": "Rupture of an aneurysm"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old man is brought to the emergency department 25 minutes after being involved in a high-speed motor vehicle collision in which he was a restrained passenger. On arrival, he has shortness of breath and is in severe pain. His pulse is 130/min, respirations are 35/min, and blood pressure is 90/40 mm Hg. Examination shows superficial abrasions and diffuse crepitus at the left shoulder level. Cardiac examination shows tachycardia with no murmurs, rubs, or gallops. The upper part of the left chest wall moves inward during inspiration. Breath sounds are absent on the left. He is intubated and mechanically ventilated. Two large bore intravenous catheters are placed and infusion of 0.9% saline is begun. Which of the following is the most likely cause of his symptoms?", "answer": "Flail chest", "options": {"A": "Diaphragmatic rupture", "B": "Phrenic nerve paralysis", "C": "Cardiac tamponade", "D": "Sternal fracture", "E": "Flail chest"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old man presents to the emergency room with blurred vision, lightheadedness, and chest pain that started 30 minutes ago. The patient is awake and alert. His history is significant for uncontrolled hypertension, coronary artery disease, and he previously underwent percutaneous coronary intervention. He is afebrile. The heart rate is 102/min, the blood pressure is 240/135 mm Hg, and the O2 saturation is 100% on room air. An ECG is performed and shows no acute changes. A rapid intravenous infusion of a drug that increases peripheral venous capacitance is started. This drug has an onset of action that is less than 1 minute with rapid serum clearance than necessitates a continuous infusion. What is the most severe side effect of this medication?", "answer": "Cyanide poisoning", "options": {"A": "Cyanide poisoning", "B": "Lupus-like syndrome", "C": "Status asthmaticus", "D": "Intractable headache", "E": "Increased intraocular pressure"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 75-year-old man is brought to the emergency department because of a 5-hour history of worsening chest pain and dyspnea. Six days ago, he fell in the shower and since then has had mild pain in his left chest. He appears pale and anxious. His temperature is 36.5°C (97.7°F), pulse is 108/min, respirations are 30/min, and blood pressure is 115/58 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 88%. Examination shows decreased breath sounds and dullness to percussion over the left lung base. There is a 3-cm (1.2-in) hematoma over the left lower chest. An x-ray of the chest shows fractures of the left 8th and 9th rib, increased opacity of the left lung, and mild tracheal deviation to the right. Which of the following is the most appropriate next step in management?", "answer": "Chest tube insertion in the fifth intercostal space at the midaxillary line\n\"", "options": {"A": "Admission to the ICU and observation", "B": "Needle thoracentesis in the eighth intercostal space at the posterior axillary line", "C": "Emergency thoracotomy", "D": "Pericardiocentesis", "E": "Chest tube insertion in the fifth intercostal space at the midaxillary line\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 36-year-old woman comes to the physician because of growths around her anus that developed over the past 4 weeks. They are not painful and she does not have blood in her stool. She is sexually active with two male partners and uses condoms inconsistently. She appears healthy. Vital signs are within normal limits. Examination shows nontender, irregular, hyperkeratotic sessile lesions in the perianal area around 4–7 mm in diameter. There is no lymphadenopathy. The application of a dilute solution of acetic acid turns the lesions white. Which of the following is the most likely cause of the lesions?", "answer": "Human papilloma virus", "options": {"A": "Poxvirus", "B": "Treponema pallidum", "C": "Malignant transformation", "D": "Benign fibroepithelial growth", "E": "Human papilloma virus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old woman comes to the physician because of intermittent episodes of cramping lower abdominal pain and bloating over the past 3 months. These episodes are often associated with non-bloody, watery, frothy stools, and excessive flatulence. The cramping does not subside after defecation. She reports that her symptoms typically begin an hour or two after eating ice cream, cheese, or pudding. She is otherwise healthy. Her only medication is an iron supplement and an oral contraceptive pill. The patient's height is 158 cm (5 ft 2 in) and her weight is 59 kg (130 lb); her BMI is 23.6 kg/m2. Abdominal examination is normal. Which of the following is the most appropriate next step in management?", "answer": "Hydrogen breath test", "options": {"A": "Fecal fat test", "B": "D-xylose absorption test", "C": "Jejunal biopsy", "D": "Hydrogen breath test", "E": "Serum IgE levels"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 56-year-old woman presents with 5-day history of progressively worsening shortness of breath and bilateral pleuritic chest pain. She also has been having associated fatigue, low grade fever, and night sweats. Her temperature is 38.1°C (100.6°F), pulse is 106/min, respiratory rate is 26/min, and blood pressure is 136/88 mm Hg. On physical examination, she is diaphoretic and in mild respiratory distress. Cardiac auscultation reveals a faint 2/6 systolic murmur best heard over the lower left sternal border. Her neck veins are distended, and abdominal examination shows significant hepatomegaly. Echocardiography is performed and results are shown below. Which of the following is the most likely underlying cause of this patient’s clinical presentation?", "answer": "Infective endocarditis", "options": {"A": "Fat embolism", "B": "Infective endocarditis", "C": "Myocardial infarction", "D": "Rheumatic fever", "E": "Small cell lung cancer"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 78-year-old female presents to her primary care provider complaining of shaking of her hands. She reports that her hands shake when she is pouring her coffee in the morning and when she is buttoning her shirt. She has noticed that her tremor improves with the several beers she has every night with dinner. She has a past medical history of hypertension, atrial fibrillation, moderate persistent asthma, acute intermittent porphyria, and urinary retention. Her home medications include hydrochlorothiazide, warfarin, bethanechol, low-dose inhaled fluticasone, and an albuterol inhaler as needed. On physical exam, she has an irregularly irregular heart rhythm without S3/S4. She has mild wheezing on pulmonary exam. She has no tremor when her hands are in her lap. A low-amplitude tremor is present during finger-to-nose testing. Her neurological exam is otherwise unremarkable.\n\nWhich of the following is a contraindication to the first-line treatment of this condition?", "answer": "Asthma", "options": {"A": "Acute intermittent porphyria", "B": "Asthma", "C": "Heavy alcohol use", "D": "Urinary retention", "E": "Warfarin use"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old woman, gravida 1, para 0, at 16 weeks' gestation comes to the physician for a routine prenatal visit. She feels well. She has no history of serious illness. She has smoked one pack of cigarettes daily for 10 years but quit when she learned she was pregnant. She does not drink alcohol or use illicit drugs. Her mother has type 1 diabetes mellitus, and her father has asthma. Current medications include a prenatal multivitamin. She appears well. Her vital signs are within normal limits. Physical examination shows no abnormalities. Serum studies show:\nAlpha-fetoprotein decreased\nUnconjugated estriol decreased\nHuman chorionic gonadotropin increased\nInhibin A increased\nDuring counseling regarding the potential for fetal abnormalities, the patient says that she would like a definitive diagnosis as quickly as possible. Which of the following is the most appropriate next step in management?\"", "answer": "Amniocentesis", "options": {"A": "Reassurance", "B": "Cell-free fetal DNA testing", "C": "Amniocentesis", "D": "Chorionic villus sampling", "E": "Pelvic ultrasound"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old black male otherwise healthy presents for a yearly physical. No significant past medical history. Current medications are a multivitamin and rosuvastatin 20 mg orally daily. Vitals are temperature 37°C (98.6°F), blood pressure 155/75 mm Hg, pulse 95/min, respirations 16/min, and oxygen saturation 99% on room air. On physical examination, the patient is alert and cooperative. The cardiac exam is significant for a high-pitched diastolic murmur loudest at the left sternal border. Peripheral pulses are bounding and prominent followed by a quick collapse on palpation. Lungs are clear to auscultation. The abdomen is soft and nontender. Chest X-ray is normal. ECG is significant for left axis deviation and broad bifid P-waves in lead II. Transthoracic echocardiography shows a bicuspid aortic valve, severe aortic regurgitation, left atrial enlargement and left ventricular dilatation and hypertrophy. Left ventricular ejection fraction is 45%. Which of the following is the best course of treatment for this patient?", "answer": "Admit to hospital for aortic valve replacement", "options": {"A": "Reassurance and recommend long-term follow-up with outpatient cardiology for clinical surveillance with regular echocardiography", "B": "Outpatient management on nifedipine 45 mg orally daily", "C": "Outpatient management on enalapril 10 mg orally twice daily", "D": "Administer dobutamine and nitroprusside", "E": "Admit to hospital for aortic valve replacement"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 44-year-old woman presents to the outpatient infectious disease clinic. She has a known history of HIV, well-controlled on HAART for the past 8 years. She currently has no additional significant medical conditions. She feels well and a physical examination is within normal limits. She denies any current tobacco use, alcohol use, or illicit drug use, although she has a history of heroin use (injection). Her vital signs include: temperature, 36.7°C (98.0°F); blood pressure, 126/74 mm Hg; heart rate, 87/min; and respiratory rate, 17/min. She has no complaints and is up to date on all of her vaccinations and preventative care. Which of the following malignancies can be seen and is often associated with AIDS?", "answer": "Kaposi’s sarcoma", "options": {"A": "Colonic adenocarcinoma", "B": "Kaposi’s sarcoma", "C": "Secondary osteosarcoma", "D": "Thymomas", "E": "Malignant melanoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 13-year-old boy presents to the emergency department with severe right-lower-quadrant abdominal pain. Workup reveals acute appendicitis, and he subsequently undergoes laparoscopic appendectomy. The appendix is sent for histological examination. A pathologist reviews the slide shown in the image below. Which statement about the structures marked within the yellow circles is correct?", "answer": "In children, appendicitis can frequently arise from certain changes in these structures.", "options": {"A": "In children, appendicitis can frequently arise from certain changes in these structures.", "B": "The only part of the digestive system in which this structure can be found is the appendix.", "C": "Neutrophils are the major components of these structures.", "D": "These structures are not normally present within the appendix.", "E": "These structures belong to the primary lymphatic system."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old female college student is brought to the university clinic by her roommates. They became worried because they noted long strands of hair all over the dormitory room floor. This has progressively worsened, with the midterms approaching. During discussions with the physician, the roommates also mention that she aggressively manipulates her scalp when she becomes upset or stressed. Physical examination reveals an otherwise well but anxious female with patches of missing and varying lengths of hair. A dermal biopsy is consistent with traumatic alopecia. What is the single most appropriate treatment for this patient?", "answer": "Cognitive-behavior therapy or behavior modification", "options": {"A": "Cognitive-behavior therapy or behavior modification", "B": "Clomipramine", "C": "Venlafaxine", "D": "Phenelzine", "E": "Electroconvulsive therapy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 47-year-old Hispanic man presents with complaints of recent heat intolerance and rapid heart rate. The patient has also experienced recent unintentional weight loss of 15 pounds. Physical exam reveals tachycardia and skin that is warm to the touch. A radioactive iodine uptake scan of the thyroid reveals several focal nodules of increased iodine uptake. Prior to this study, the physician had also ordered a serum analysis that will most likely show which of the following?", "answer": "Low TSH and high T4", "options": {"A": "High TSH and low T4", "B": "Low TSH and high T4", "C": "High TSH and normal T4", "D": "High TSH and high T4", "E": "Low TSH and low T4"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 74-year-old man is brought to the emergency department because of increasing abdominal pain and distention for 3 days. The pain is diffuse and colicky, and he describes it as 4 out of 10 in intensity. His last bowel movement was 5 days ago. He has not undergone any previous abdominal surgeries. He has hypertension, chronic lower back pain, coronary artery disease, and hypercholesterolemia. Prior to admission, his medications were enalapril, gabapentin, oxycodone, metoprolol, aspirin, and simvastatin. He appears uncomfortable. His temperature is 37.3°C (99.1°F), pulse is 93/min, and blood pressure is 118/76 mm Hg. Examination shows a distended and tympanitic abdomen; bowel sounds are reduced. There is mild tenderness to palpation in the lower abdomen with no guarding or rebound. Rectal examination shows an empty rectum. Laboratory studies show:\nHemoglobin 13.1 g/dL\nSerum\nNa+ 134 mEq/L\nK+ 2.7 mEq/L\nCl- 98 mEq/L\nUrea nitrogen 32 mg/dL\nCreatinine 1 mg/dL\nAn x-ray of the abdomen shows a dilated cecum and right colon and preservation of the haustrae. A CT scan of the abdomen and pelvis with contrast shows a cecal diameter of 11 cm. The patient is kept NPO and intravenous fluids with electrolytes are administered. A nasogastric tube and rectal tube are inserted. Thirty-six hours later, he still has abdominal pain. Examination shows a distended and tympanitic abdomen. Serum concentrations of electrolytes are within the reference range. Which of the following is the most appropriate next step in management?\"", "answer": "Neostigmine therapy", "options": {"A": "Percutaneous cecostomy", "B": "Neostigmine therapy", "C": "Laparotomy", "D": "Metronidazole therapy", "E": "Colonoscopy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old man comes to the physician because of a 2-day history of a rash across his trunk and extremities. For the past 3 months, he has had persistent pruritus in these areas. He started hiking in the woods with his grandson last week to try to lose weight. His grandson, who often spends the weekends with him, recently had impetigo. He has hypertension, hyperlipidemia, and osteoarthritis of his thumbs. Five months ago, he was treated for a gout attack of his left hallux. Current medications include captopril, hydrochlorothiazide, simvastatin, allopurinol, and ibuprofen. Vital signs are within normal limits. There are diffuse vesicles and tense blisters involving the chest, flexures of the arms, and shoulders. Rubbing the skin on his chest does not produce blisters. Oral examination shows no abnormalities. This patient's condition is most likely associated with which of the following findings?", "answer": "Linear deposits of IgG and C3 along the basement membrane on direct immunofluorescence studies", "options": {"A": "Growth of Gram-positive bacteria on blood culture", "B": "Antibodies to tissue transglutaminase on serologic testing", "C": "Linear deposits of IgG and C3 along the basement membrane on direct immunofluorescence studies", "D": "Spongiotic dermatitis on skin biopsy", "E": "Subepidermal separation with full thickness epidermal necrosis on skin biopsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old man is undergoing chemotherapy treatment for a rapidly progressive newly-diagnosed acute myelogenous leukemia. On day 4 of his hospitalization, the patient is noted to be obtunded. Other than the chemotherapy, he is receiving lansoprazole, acetaminophen, and an infusion of D5–0.9% normal saline at 50 mL/h. On examination, the patient’s blood pressure is 94/50 mm Hg, heart rate is 52/min, and respiratory rate is 14/min. The patient appears weak but is in no acute distress. Chest auscultation reveals bibasilar crackles and scattered wheezing. His abdomen is soft, non-distended, and with a palpable liver and spleen. His ECG shows peaked T waves and widened QRS complexes. What is the best next step in the management of this patient?", "answer": "Calcium chloride", "options": {"A": "Glucagon", "B": "Subcutaneous regular insulin", "C": "Polystyrene sulfonate", "D": "Calcium chloride", "E": "Atropine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy is brought to the pediatrician’s office for a flu-like episode. His father tells the physician that his child has fallen ill several times over the past few months. He also has occasional bouts of night sweats and loss of appetite. He has lost 5 lbs (2.3 kg) in the last 6 months. At the pediatrician’s office, his temperature is 38.9°C (102°F), pulse is 105/min and respiration rate is 18/min. On physical examination, the pediatrician observes a flattened facial profile, prominent epicanthal folds, and a single palmar crease. There are petechiae on the arms and legs. Blood count shows pancytopenia. Bone marrow aspiration is diagnostic for ALL (acute lymphoblastic leukemia), but all cells also show a trisomy. Children with similar genetic anomalies are at an increased risk of developing which of the following neurological conditions as they grow older?", "answer": "Alzheimer’s disease", "options": {"A": "Lewy body dementia", "B": "Alzheimer’s disease", "C": "Amyotrophic lateral sclerosis", "D": "Pick’s disease", "E": "Parkinson’s dementia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 21-year-old man comes to the military base physician for evaluation of progressive discomfort in his right shoulder for the past 4 months. He joined the military 6 months ago and is part of a drill team. In anticipation of an upcoming competition, he has been practicing rifle drills and firing exercises 8 hours a day. Physical examination shows tenderness to palpation and a firm mass in the superior part of the right deltopectoral groove. Range of motion is limited by pain and stiffness. Which of the following is the most likely diagnosis?", "answer": "Myositis ossificans", "options": {"A": "Osteoid osteoma", "B": "Lipoma", "C": "Acromioclavicular joint separation", "D": "Myositis ossificans", "E": "Arteriovenous fistula"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old girl is brought to the physician by her mother because of a 3-week history of a foul-smelling discharge from the left nostril. There was one episode of blood-tinged fluid draining from the nostril during this period. She has been mouth-breathing in her sleep for the past 4 days. She was born at term. Her 1-year-old brother was treated for viral gastroenteritis 3 weeks ago. She is at 60th percentile for height and at 70th percentile for weight. Her temperature is 37°C (98.6°F), pulse is 96/min, respirations are 23/min, and blood pressure is 96/54 mm Hg. Examination shows mucopurulent discharge in the left nasal cavity. Oral and otoscopic examination is unremarkable. Endoscopic examination of the nose confirms the diagnosis. Which of the following is the most appropriate next step in management?", "answer": "Foreign body extraction", "options": {"A": "Transnasal puncture and stenting", "B": "Foreign body extraction", "C": "Perform septoplasty", "D": "Adenoidectomy", "E": "Intranasal glucocorticoid therapy\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 57-year-old man is brought to the emergency department because of a 3-day history of fever and headache. He also has nausea and vomited twice in the past 24 hours. His temperature is 39.1°C (102.4°F). He is lethargic but oriented to person, place, and time. Examination shows severe neck rigidity with limited active and passive range of motion. A lumbar puncture is performed; cerebrospinal fluid analysis shows a neutrophilic pleocytosis and a decreased glucose concentration. A Gram stain of the patient's cerebrospinal fluid is most likely to show which of the following?", "answer": "Encapsulated, gram-positive cocci in pairs", "options": {"A": "Non-encapsulated, gram-negative cocci in pairs", "B": "Gram-positive cocci in clusters", "C": "Gram-negative bacilli", "D": "Encapsulated, gram-positive cocci in pairs", "E": "Gram-positive bacilli"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old G2P0 presents to her physician to discuss the results of her 16-week obstetric screening tests. She has no complaints. Her previous pregnancy at 28 years of age was a spontaneous abortion in the first trimester. She has no history of gynecologic diseases. Her quadruple test shows the following findings:\nAlpha-fetoprotein\nLow\nBeta-hCG\nHigh\nUnconjugated estriol\nLow\nInhibin A\nHigh\nWhich of the following statements regarding the presented results is correct?\n ", "answer": "Maternal age is a significant risk factor for the condition of the patient, the increased risk of which is indicated by the results of the study.", "options": {"A": "Such results are associated with a 100% lethal fetal condition.", "B": "Maternal age is a significant risk factor for the condition of the patient, the increased risk of which is indicated by the results of the study.", "C": "Such results are a strong indicator of a monogenic disease.", "D": "The obtained results can be normal for women aged 35 and older.", "E": "The results show increased chances of aneuploidies associated with the sex chromosomes."}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old man comes to the clinic complaining of yellow discoloration of his skin and eyes for the past week. He also complains about loss of appetite, nausea, malaise, and severe tiredness. He has no known past medical history and takes over-the-counter acetaminophen for headache. He has smoked a half pack of cigarettes every day for the last 15 years and drinks alcohol occasionally. He has been sexually active with a new partner for a month and uses condoms inconsistently. His father and mother live in China, and he visited them last year. Temperature is 37°C (98.7°F), blood pressure is 130/90 mm Hg, pulse is 90/min, respirations are 12/min, and BMI is 25 kg/m2. On physical examination, his sclera and skin are icteric. Cardiopulmonary examination is negative, no lymphadenopathy is noted, and his abdomen is tender in the right upper quadrant (RUQ). His liver is palpated 3 cm below the costal margin. On laboratory investigations:\nLaboratory test\nComplete blood count \nHemoglobin 15 g/dL\nLeucocytes 13,000/mm3\nPlatelets 170,000/mm3\nBasic metabolic panel \nSerum Na+ 133 mEq/L\nSerum K+ 3.6 mEq/L\nSerum Cl- 107 mEq/L\nSerum HCO3- 26 mEq/L\nBUN 12 mg/dL\nLiver function test \nSerum bilirubin 3.4 mg/dL\nDirect bilirubin 2.5 mg/dL\nAST 2,100 U/L\nALT 2,435 U/L\nALP 130 U/L\nWhat is the next best step to do in this patient?", "answer": "HbsAg and Anti-IgM Hbc", "options": {"A": "USG of the abdomen", "B": "CT scan of the abdomen", "C": "Reassurance and counselling", "D": "HbsAg and Anti-IgM Hbc", "E": "ERCP"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old woman presents with loss of sensation in her left arm and hand. A rapid evaluation is performed to rule out stroke. No other focal neurologic deficits are found except for a loss of fine touch sensation in a C6 dermatome pattern. Further evaluation reveals that the patient was recently sick with an upper respiratory infection. A biopsy is performed and shows destruction of the cell bodies of sensory nerves. Which of the following structures is most likely been damaged?", "answer": "Dorsal root ganglion", "options": {"A": "Meissner's corpuscles", "B": "Dorsal root ganglion", "C": "Ventral root ganglion", "D": "Dorsal column", "E": "Lateral corticospinal tract"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Lipidator is a nonionic surfactant that is used to disrupt the lipid membranes of cells. This disruption of the lipid membrane results in the release of all of its cytoplasmic contents. Which of the following viruses would not be disrupted if treated with this detergent?", "answer": "Picornavirus", "options": {"A": "Herpesvirus", "B": "Hepadnavirus", "C": "Flavivirus", "D": "Picornavirus", "E": "HIV"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old woman presents to her primary care physician with a 1-week history of facial drooping. Specifically, she has noticed that the left side of her face does not move when she tries to smile. Furthermore, she has been having difficulty closing her left eye. Her past medical history is significant for hypertension but she does not have any known prior neurological deficits. Imaging reveals a cranial mass that is compressing an adjacent nerve. Which tumor location would most likely be associated with this patient's symptoms?", "answer": "Internal auditory meatus", "options": {"A": "Foramen ovale", "B": "Internal auditory meatus", "C": "Jugular foramen", "D": "Optic canal", "E": "Superior orbital fissure"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old woman comes to the physician because of a 5-month history of insomnia. She frequently experiences leg discomfort when trying to fall asleep that is relieved temporarily by movement. Her husband tells her that she frequently flexes her ankles upward when she sleeps. She appears fatigued and anxious. Physical examination shows no abnormalities. Laboratory studies including a complete blood count and iron studies are within the reference range. Which of the following is the most appropriate pharmacotherapy?", "answer": "Ropinirole", "options": {"A": "Ropinirole", "B": "Zolpidem", "C": "Nortriptyline", "D": "Atenolol", "E": "Sertraline"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man comes to the emergency department for progressively worsening abdominal pain. The pain began 2 weeks ago and is localized to the right upper quadrant. He feels sick and fatigued. He also reports breathlessness when climbing the stairs to his first-floor apartment. He is a retired painter. He has hypertension and type 2 diabetes mellitus. He is sexually active with one female partner and does not use condoms consistently. He began having sexual relations with his most recent partner 2 months ago. He smoked 1 pack of cigarettes daily for 40 years but quit 10 years ago. He does not drink alcohol. Current medications include insulin and enalapril. He is 181 cm (5 ft 11 in) tall and weighs 110 kg (264 lb); BMI is 33.5 kg/m2. His vital signs are within normal limits. Physical examination shows jaundice, a distended abdomen, and tender hepatomegaly. There is no jugular venous distention. A grade 2/6 systolic ejection murmur is heard along the right upper sternal border. Laboratory studies show:\nHemoglobin 18.9 g/dL\nAspartate aminotransferase 450 U/L\nAlanine aminotransferase 335 U/L\nTotal bilirubin 2.1 mg/dL\nWhich of the following is the most likely cause of his symptoms?\"", "answer": "Hepatic vein obstruction", "options": {"A": "Hepatotropic viral infection", "B": "Increased iron absorption", "C": "Hepatic vein obstruction", "D": "Thickened pericaridium", "E": "Hepatic steatosis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 59-year-old man is brought to the emergency department because of a 2-hour history of abdominal pain and severe vomiting after ingesting an unknown medication in a suicide attempt. On the way to the hospital, he had a generalized tonic-clonic seizure. He has chronic obstructive pulmonary disease, coronary artery disease, and chronic back pain. His pulse is 130/min, respirations are 16/min, and blood pressure is 110/60 mm Hg. Serum studies show a glucose concentration of 180 mg/dL and a potassium concentration of 2.8 mEq/L. An ECG shows ventricular tachycardia. This patient's current findings are most likely caused by an overdose of which of the following drugs?", "answer": "Theophylline", "options": {"A": "Albuterol", "B": "Theophylline", "C": "Metoprolol", "D": "Amitriptyline", "E": "Acetaminophen\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old woman presents to the clinic today complaining of weakness and fatigue. She is a vegetarian and often struggles to maintain an adequate intake of non-animal based protein. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and she currently denies any illicit drug use. Her past medical history is non-contributory. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 16/min. On physical examination, her pulses are bounding, the complexion is pale, the breath sounds are clear, and the heart sounds are normal. The spleen is mildly enlarged. Oxygen saturation was initially 81% on room air, with a new oxygen requirement of 8 L by face mask. She is at a healthy body mass index (BMI) of 22 kg/m2. The laboratory results indicate: mean corpuscular volume MCV: 71 fL, Hgb: 11.0, total iron-binding capacity (TIBC): 412 mcg/dL, transferrin saturation (TSAT): 11%. What is the most appropriate treatment for this patient?", "answer": "Iron replacement for 4–6 months", "options": {"A": "Iron replacement for 4–6 months", "B": "Lifelong Vitamin B6 supplementation", "C": "Lifelong Vitamin B1 supplementation", "D": "Folic acid supplementation", "E": "Obtain a bone-marrow biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An autopsy was performed on a 2-year-old male child. The clinical report stated that the child's parents were first cousins, and that he had deteriorated physically and mentally over the past year, becoming deaf, unable to eat, and paralyzed. A brain biopsy demonstrated the accumulation of GM2-gangliosides in the neurons. Which of the following enzymes was missing from this child?", "answer": "Hexosaminidase A", "options": {"A": "Sphingomyelinase", "B": "a-galactosidase A", "C": "ß-galactocerebrosidase", "D": "Hexosaminidase A", "E": "a-L-iduronidase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 70-year-old woman comes to the physician for a follow-up examination 2 months after undergoing a total hip replacement surgery. She reports that she has persistent difficulty in walking since the surgery despite regular physiotherapy. Examination of her gait shows sagging of the left pelvis when her right leg is weight-bearing. Which of the following nerves is most likely to have been injured in this patient?", "answer": "Right superior gluteal nerve", "options": {"A": "Left superior gluteal nerve", "B": "Right femoral nerve", "C": "Left inferior gluteal nerve", "D": "Left femoral nerve", "E": "Right superior gluteal nerve"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old man seeks evaluation at a clinic with a 2-week history of pain during urination and a yellow-white discharge from the urethra. He has a history of multiple sexual partners and inconsistent use of condoms. He admits to having similar symptoms in the past and being treated with antibiotics. On genital examination, solitary erythematous nodules are present on the penile shaft with a yellow-white urethral discharge. The urinalysis was leukocyte esterase-positive, but the urine culture report is pending. Gram staining of the urethral discharge showed kidney bean-shaped diplococci within neutrophils. Urethral swabs were collected for cultures. Which of the following best explains why this patient lacks immunity against the organism causing his recurrent infections?", "answer": "Protein pili", "options": {"A": "Lipooligosaccharide", "B": "Protein pili", "C": "Exotoxin", "D": "Lack of vaccine", "E": "Complement deficiency"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman is diagnosed with schizophrenia after nine months of experiencing auditory hallucinations and persecutory delusions. Over the next year, she fails to experience symptom relief from separate and appropriately dosed trials of olanzapine, quetiapine, and risperidone. At this point, which of the following treatment options is most likely to be effective?", "answer": "Clozapine", "options": {"A": "Aripiprazole", "B": "Haloperidol", "C": "Clozapine", "D": "Clonidine", "E": "Cognitive behavioral therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 54-year-old woman comes to the physician because of an ulcer on her left ankle for 6 years. She has had multiple ulcers over her left lower extremity during this period that have subsided with wound care and dressing. She has type 2 diabetes mellitus and gastroesophageal reflux disease. Current medications include metformin, sitagliptin, and omeprazole. She appears anxious. She is 162 cm (5 ft 4 in) tall and weighs 89 kg (196 lb); BMI is 34 kg/m2. Vital signs are within normal limits. Examination shows a 7.5-cm (3-in) ulcer with elevated, indurated margins and a necrotic floor above the left medial malleolus. There are multiple dilated, tortuous veins along the left lower extremity. There is 2+ pretibial edema of the lower extremities bilaterally. The skin around the left ankle appears darker than the right and there are multiple excoriation marks. Cardiopulmonary examination shows no abnormalities. Which of the following is the most appropriate next step in management of this patient's current condition?", "answer": "Punch biopsy\n\"", "options": {"A": "Digital subtraction angiography", "B": "CT scan of the left leg", "C": "Perthes test", "D": "Trendelenburg test", "E": "Punch biopsy\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 60-year-old woman presents to you with vision problems. Objects appear clear, but she just can't see as well as before. She says she first noticed this when she went to the movies with her grandkids, and she could not see the whole screen. She denies any complaints of redness, itchiness, or excessive tearing of her eyes. Current medications are captopril for her hypertension, acetaminophen for occasional headaches, and a daily multivitamin. Her vital signs are a blood pressure 130/80 mm Hg, pulse 80/min and regular, respiratory rate 14/min, and a temperature of 36.7°C (98.0°F). Eye examination reveals that her visual acuity is normal but the visual field is reduced with enlarged blind spots. Tonometry reveals mildly increased IOP. The patient is started on brimonidine. Which of the following statements best describes the therapeutic mechanism of action of this medication in this patient?", "answer": "Brimonidine causes release of prostaglandins that relax the ciliary muscle and increases uveoscleral outflow.", "options": {"A": "Brimonidine causes an increase in cAMP, leading to increased aqueous humor formation by the ciliary body.", "B": "Brimonidine causes immediate contraction of the ciliary body, leading to decreased uveoscleral outflow.", "C": "Brimonidine blocks the beta-receptors on the ciliary body to reduce aqueous humor production.", "D": "Peripheral vasoconstriction by brimonidine leads to better control of her hypertension.", "E": "Brimonidine causes release of prostaglandins that relax the ciliary muscle and increases uveoscleral outflow."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old woman presents to the office because she has noticed yellowish bumps and patches on her elbows and knees that seem to come and go. Recently she noticed the same yellow bumps on her eyelids. She is a new patient and reports that she is otherwise healthy but did not have insurance until recently so she has not been to the doctor in over 8 years. Past medical history is significant for occasional headaches that she treats with aspirin. She used to smoke a pack a day for the last 20 years but recently quit. Her father died of a heart attack at the age of 55 years and her mother had a stroke at 64 and lives in a nursing home. Her blood pressure is 135/87 mm Hg, the heart rate is 95/min, the respiratory rate is 12/min, and the temperature is 37.0°C (98.6°F). On physical exam, she has multiple tan-yellow, firm papules on her knees and elbows. The papules around her eyes are smaller and soft. You discuss the likely cause of the bumps and explain that you will need to order additional tests. What test should you perform?", "answer": "Lipid panel", "options": {"A": "Biopsy", "B": "PET scan", "C": "Celiac panel", "D": "Lipid panel", "E": "Erythrocyte sedimentation rate (ESR)"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 47-year-old woman comes to the emergency department because of a 2-week history of fatigue, abdominal distention, and vomiting. She drinks 6 beers daily. Physical examination shows pallor and scleral icterus. A fluid wave and shifting dullness are present on abdominal examination. The intravascular pressure in which of the following vessels is most likely to be increased?", "answer": "Short gastric vein", "options": {"A": "Short gastric vein", "B": "Splenic artery", "C": "Inferior epigastric vein", "D": "Azygos vein", "E": "Gastroduodenal artery"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "One month after undergoing surgical spinal fusion because of a traumatic spinal cord injury, a 68-year-old man comes to the physician because of lower abdominal pain. He last voided yesterday. Physical examination shows a suprapubic mass and decreased sensation below the umbilicus. Urodynamic studies show simultaneous contractions of the detrusor muscle and the internal urethral sphincter. Urinary catheterization drains 900 mL of urine from the bladder. Which of the following is the most appropriate pharmacotherapy for this patient’s urinary symptoms?", "answer": "Prazosin", "options": {"A": "Neostigmine", "B": "Finasteride", "C": "Phenylephrine", "D": "Bethanechol", "E": "Prazosin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old African American male with sickle cell disease has been followed by a hematologist since infancy. Two years ago, he was started on hydroxyurea for frequent pain crises but has not achieved good control. The addition of a Gardos channel blocking agent is being considered. What is the mechanism of action of this class of medications?", "answer": "Prevents RBC dehydration by inhibiting K+ efflux", "options": {"A": "Prevents RBC dehydration by inhibiting K+ efflux", "B": "Increases production of hemoglobin F", "C": "Prevents dehydration of RBCs by inhibiting Ca2+ efflux", "D": "Encourages alkalinization of the blood by facilitating H+/K+ antiporter activity", "E": "Increases water diffusion by increasing activity of aquaporin-1 receptors"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 5-year-old boy is brought to the physician by his parents because of a 2-day history of poor balance and difficulty walking. He has fallen multiple times and is unable to walk up the stairs unassisted. He has also had difficulty tying his shoes and dressing himself. His family adheres to a vegetarian diet. He has not yet received any routine childhood vaccinations. His mother has a history of anxiety. He is at the 70th percentile for height and 30th percentile for weight. Vital signs are within normal limits. He is alert and oriented to person, place, and time. Physical examination shows a broad-based, staggering gait. He has difficulty touching his nose and cannot perform rapidly-alternating palm movements. Strength is 5/5 in the upper and lower extremities. Deep tendon reflexes are 1+ bilaterally. Skin examination shows several faint hyperpigmented macules on the chest. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Varicella zoster infection", "options": {"A": "Vitamin B1 deficiency", "B": "Varicella zoster infection", "C": "Accidental medication ingestion", "D": "Posterior fossa malignancy", "E": "Peripheral nerve demyelination"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old female presents to her primary care physician with a 1-month history of facial and chest flushing, as well as intermittent diarrhea and occasional difficulty breathing. On physical exam, a new-onset systolic ejection murmur is auscultated and is loudest at the left second intercostal space. Subsequent echocardiography reveals leaflet thickening secondary to fibrous plaque deposition on both the pulmonic and tricuspid valves. Which of the following laboratory abnormalities would most likely in this patient?", "answer": "Elevated urinary 5-hydroxyindoleacetic acid", "options": {"A": "Decreased serum chromogranin A", "B": "Elevated serum bicarbonate", "C": "Elevated urinary vanillylmandelic acid", "D": "Elevated serum potassium", "E": "Elevated urinary 5-hydroxyindoleacetic acid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 53-year-old man is brought to the clinic by his son for the evaluation of unusual behavior. He is a shopkeeper by profession and sometimes behaves very rudely to the customers. Recently, he accused one of the customers of using black magic over his shop. He has been increasingly irritable, forgetting things, and having problems managing his finances over the past 8 months. He is also having difficulty finding words and recalling the names of objects during the conversation. There is no history of recent head trauma, fever, hallucinations, or abnormal limb movements. Past medical history is significant for a well-controlled type 2 diabetes mellitus. Family history is unremarkable. He does not smoke or use illicit drugs. Vital signs are stable with a blood pressure of 134/76 mm Hg, a heart rate of 88/min, and a temperature of 37.0°C (98.6°F). On physical examination, he has problems naming objects and planning tasks. Mini-mental state examination (MMSE) score is 26/30. Cranial nerve examination is normal. Muscle strength is normal in all 4 limbs with normal muscle tone and deep tendon reflexes. Sensory examination is also normal. What is the most likely diagnosis?", "answer": "Pick’s disease", "options": {"A": "Alzheimer’s disease", "B": "Creutzfeldt–Jakob disease", "C": "Huntington’s disease", "D": "Lewy body dementia", "E": "Pick’s disease"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old G0P0 African American woman presents to the physician with complaints of heavy menstrual bleeding as well as menstrual bleeding in between her periods. She also reports feeling fatigued and having bizarre cravings for ice and chalk. Despite heavy bleeding, she does not report any pain with menstruation. Physical examination is notable for an enlarged, asymmetrical, firm uterus with multiple palpable, non-tender masses. Biopsy confirms the diagnosis of a benign condition. Which of the following histological characteristics would most likely be seen on biopsy in this patient?", "answer": "Whorled pattern of smooth muscle bundles with well-defined borders", "options": {"A": "Clustered pleomorphic, hyperchromatic smooth muscle cells with extensive mitosis", "B": "Granulosa cells scattered around collections of eosinophilic fluid", "C": "Laminated, concentric spherules with dystrophic calcification", "D": "Presence of endometrial glands and stroma in the myometrium", "E": "Whorled pattern of smooth muscle bundles with well-defined borders"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A young immigrant girl presents with low-grade fever, sore throat, painful swallowing, and difficulty in breathing. Her voice is unusually nasal and her swollen neck gives the impression of “bull's neck”. On examination, a large gray membrane is noticed on the oropharynx as shown in the picture. Removal of the membrane reveals a bleeding edematous mucosa. Culture on potassium tellurite medium reveals several black colonies. What is the mechanism of action of the bacterial toxin responsible for this condition?", "answer": "ADP ribosylates EF-2 and prevents protein synthesis (ADP = adenosine diphosphate; EF-2 = elongation factor-2)", "options": {"A": "Travels retrogradely on axons of peripheral motor neurons and blocks the release of inhibitory neurotransmitters", "B": "Spreads to peripheral cholinergic nerve terminals and blocks the release of acetylcholine ", "C": "Cytotoxic to cells", "D": "ADP ribosylates EF-2 and prevents protein synthesis (ADP = adenosine diphosphate; EF-2 = elongation factor-2)", "E": "Causes muscle cell necrosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old man is brought to the emergency department by ambulance after he was found to be altered at home. Specifically, his wife says that he fell and was unable to get back up while walking to bed. When she approached him, she found that he was unable to move his left leg. His past medical history is significant for hypertension, atrial fibrillation, and diabetes. In addition, he has a 20-pack-year smoking history. On presentation, he is found to still have difficulty moving his left leg though motor function in his left arm is completely intact. The cause of this patient's symptoms most likely occurred in an artery supplying which of the following brain regions?", "answer": "Cingulate gyrus", "options": {"A": "Cingulate gyrus", "B": "Globus pallidus", "C": "Lateral medulla", "D": "Lingual gyrus", "E": "Superior temporal gyrus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 9-year-old boy is brought to the emergency room by his mother for weakness, diaphoresis, and syncope. His mother says that he has never been diagnosed with any medical conditions but has been having “fainting spells” over the past month. Routine lab work reveals a glucose level of 25 mg/dL. The patient is promptly given glucagon and intravenous dextrose and admitted to the hospital for observation. The patient’s mother stays with him during his hospitalization. The patient is successfully watched overnight and his blood glucose levels normalize on his morning levels. The care team discusses a possible discharge during morning rounds. One hour later the nurse is called in for a repeat fainting episode. A c-peptide level is drawn and shown to be low. The patient appears ill, diaphoretic, and is barely arousable. Which of the following is the most likely diagnosis in this child?", "answer": "Munchausen syndrome by proxy", "options": {"A": "Munchausen syndrome", "B": "Munchausen syndrome by proxy", "C": "Somatic symptom disorder", "D": "Conversion disorder", "E": "Insulinoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman comes to the physician because of progressive left flank pain and increased urinary frequency for the past two weeks. Her appetite is normal and she has not had any nausea or vomiting. She has a history of type 1 diabetes mellitus that is poorly controlled with insulin. She is sexually active with her boyfriend, and they use condoms inconsistently. Her temperature is 38° C (100.4° F), pulse is 90/min, and blood pressure is 120/80 mm Hg. The abdomen is soft and there is tenderness to palpation in the left lower quadrant; there is no guarding or rebound. There is tenderness to percussion along the left flank. She complains of pain when her left hip is passively extended. Her leukocyte count is 16,000/mm3 and urine pregnancy test is negative. Urinalysis shows 3+ glucose. An ultrasound of the abdomen shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Psoas muscle abscess", "options": {"A": "Urinary tract infection", "B": "Ectopic pregnancy", "C": "Nephrolithiasis", "D": "Psoas muscle abscess", "E": "Uterine leiomyoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old woman, gravida 3, para 2, delivers twins via an uncomplicated vaginal delivery. Both placentas are delivered shortly afterward. The patient received regular prenatal care and experienced no issues during her pregnancy. Over the next hour, she continues to experience vaginal bleeding, with an estimated blood loss of 1150 mL. Vital signs are within normal limits. Physical exam shows an enlarged, soft uterus. Which of the following is the most appropriate next step in management?", "answer": "Bimanual uterine massage", "options": {"A": "Methylergometrine", "B": "Hysterectomy", "C": "Curettage with suctioning", "D": "Tranexamic acid", "E": "Bimanual uterine massage"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An otherwise healthy 78-year-old man is brought to the emergency department by his daughter because of a 1-day history of a diffuse headache and an inability to understand speech. There is no history of head trauma. He drinks one to two beers daily and occasionally more on weekends. His vital signs are within normal limits. Mental status examination shows fluent but meaningless speech and an inability to repeat sentences. A noncontrast CT scan of the head shows an acute hemorrhage in the left temporal lobe and several small old hemorrhages in bilateral occipital lobes. Which of the following is the most likely underlying cause of this patient's neurological symptoms?", "answer": "Amyloid angiopathy", "options": {"A": "Vascular lipohyalinosis", "B": "Ruptured vascular malformation", "C": "Hypertensive encephalopathy", "D": "Cardiac embolism", "E": "Amyloid angiopathy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old woman presents to her primary care physician complaining of a several-month history of episodic sweating and heart racing. Her husband noticed that she becomes pale during these episodes. She also has progressive episodic pounding headaches which are not relieved by paracetamol. Her family history is negative for hypertension, endocrinopathies, or tumors. Vital signs reveal a blood pressure of 220/120 mm Hg, temperature (normal) and pulse of 110/min. Fundus examination reveals hypertensive retinal changes. This patient condition is most likely due to neoplasm arising from which of the following?", "answer": "Adrenal chromaffin cells", "options": {"A": "Zona glomerulosa", "B": "Zona fasciculata", "C": "Zonta reticularis", "D": "Adrenal chromaffin cells", "E": "Extra-adrenal chromaffin cells"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 13-year-old boy is brought to the physician because of swelling around his eyes for the past 2 days. His mother also notes that his urine became gradually darker during this time. Three weeks ago, he was treated for bacterial tonsillitis. His temperature is 37.6°C (99.7°F), pulse is 79/min, and blood pressure is 158/87 mm Hg. Examination shows periorbital swelling. Laboratory studies show:\nSerum\nUrea nitrogen 9 mg/dL\nCreatinine 1.7 mg/dL\nUrine\nProtein 2+\nRBC 12/hpf\nRBC casts numerous\nA renal biopsy would most likely show which of the following findings?\"", "answer": "Granular deposits of IgG, IgM, and C3 on immunofluorescence", "options": {"A": "\"\"\"Spike-and-dome\"\" appearance of subepithelial deposits on electron microscopy\"", "B": "Splitting and alternating thickening and thinning of the glomerular basement membrane on light microscopy", "C": "Mesangial IgA deposits on immunofluorescence", "D": "Effacement of podocyte foot processes on electron microscopy", "E": "Granular deposits of IgG, IgM, and C3 on immunofluorescence"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 71 year-old female is brought to the emergency room by her husband. The husband reports that they were taking a walk together one hour ago, when his wife experienced sudden, right arm and leg weakness. He noticed that she had slurred speech, and that she was not able to tell him where she was. The patient underwent an emergent CT scan, which was unremarkable, and was treated with tissue plasminogen activator (tPA). Which of the following EKG findings increases a patient's risk for this acute presentation?", "answer": "Atrial fibrillation", "options": {"A": "Supraventricular tachycardia", "B": "Atrial bigeminy", "C": "Normal sinus rhythm", "D": "Prolonged QT", "E": "Atrial fibrillation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old man presents with increasing neck pain for several months that does not improve with nonsteroidal anti-inflammatory drugs. The patient says he has had neck pain ever since he was involved in a motor vehicle accident 10 months ago. For the last 2 weeks, he says he has also noticed weakness and numbness in his hands and has difficulty gripping objects. Physical examination reveals a thermal injury that he says he got while holding a hot cup of coffee a week ago when he could not feel the warmth of the coffee mug. Strength is 4/5 bilaterally during elbow flexion and extension and wrist extension. He also has exaggerated deep tendon reflexes bilaterally and decreased sensation symmetrically on the dorsal and ventral surface of both forearms and hands. Which of the following additional findings would you expect to find in this patient?", "answer": "A cavitation in the cervical spinal cord", "options": {"A": "Fusion of cervical vertebrae", "B": "Hypoplasia of the cerebellar vermis", "C": "Bilateral carpal tunnel syndrome", "D": "A cavitation in the cervical spinal cord", "E": "Cervical spinal epidural abscess"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man presents to the emergency department because of fever and scrotal pain for 2 days. Medical history includes diabetes mellitus and morbid obesity. His temperature is 40.0°C (104.0°F), the pulse is 130/min, the respirations are 35/min, and the blood pressure is 90/68 mm Hg. Physical examination shows a large area of ecchymosis, edema, and crepitus in his perineal area. Fournier gangrene is suspected. A right internal jugular central venous catheter is placed without complication under ultrasound guidance for vascular access in preparation for the administration of vasopressors. Which of the following is the most appropriate next step?", "answer": "Obtain an immediate portable chest radiograph to evaluate line placement", "options": {"A": "Begin infusion of norepinephrine to maintain systolic blood pressure over 90 mm Hg", "B": "Begin infusion of normal saline through a central line", "C": "Begin to use the line after documenting the return of dark, non-pulsatile blood from all ports", "D": "Confirm line placement by ultrasound", "E": "Obtain an immediate portable chest radiograph to evaluate line placement"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old man of Asian descent presents with a skin rash after being started on prophylactic doses of trimethoprim/sulfamethoxazole 3 weeks earlier. He was diagnosed with acquired immunodeficiency syndrome (AIDS) 2 months ago which prompted the initiation of prophylactic antibiotics. The vital signs include: blood pressure 112/72 mm Hg, temperature 40.0°C (104.0°F), respiratory rate 22/min, and heart rate 95/min. He has 20% total body surface area (TBSA) skin slough with scattered vesicles and erosions throughout his face and extremities, as shown in the image. He does have erosions on his lips, but he does not have any other mucosal involvement. Which of the following is most consistent with this patient’s findings?", "answer": "Stevens-Johnson syndrome", "options": {"A": "Erythema multiforme", "B": "Staphylococcal scalded skin syndrome", "C": "Stevens-Johnson syndrome", "D": "Drug rash with eosinophilia and systemic symptoms", "E": "Toxic shock syndrome"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 43-year-old woman comes to the physician because of a 2-month history of chest pain. She describes the pain as intermittent and burning-like. She states that she has tried using proton pump inhibitors but has had no relief of her symptoms. She has had a 5-kg (11-lb) weight loss over the past 2 months. Her temperature is 36.7°C (98.1°F), pulse is 75/min, and blood pressure is 150/80 mm Hg. Examination shows tightness of the skin of the fingers; there are small nonhealing, nonpurulent ulcers over thickened skin on the fingertips. Fine inspiratory crackles are heard at both lung bases. There is mild tenderness to palpation of the epigastrium. Which of the following is most likely associated with her diagnosis?", "answer": "Anti-topoisomerase antibodies", "options": {"A": "c-ANCA", "B": "Anti-topoisomerase antibodies", "C": "Anti-mitochondrial antibodies", "D": "Anti-histone antibodies", "E": "Anti-Ro/SSA and anti-La/SSB antibodies"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old man presents to the emergency department with general weakness and fatigue. He states that he has not felt well for several days and can't take care of himself anymore due to fatigue. The patient has a past medical history of IV drug abuse, alcohol abuse, and multiple minor traumas associated with intoxication. His temperature is 104°F (40°C), blood pressure is 127/68 mmHg, pulse is 120/min, respirations are 19/min, and oxygen saturation is 98% on room air. A murmur is heard on cardiac exam. The patient is treated appropriately and transferred to the inpatient floor and recovers over the next several days. The patient has been unable to eat solids, though he has been drinking large amounts of juice. On day 5 of his stay, the patient states he feels much better. He is no longer febrile. His only concern is profuse and watery diarrhea and severe abdominal pain which he has been experiencing since yesterday. The patient is started on IV fluids and given oral fluid replacement as well. Which of the following is associated with the most likely underlying diagnosis?", "answer": "Pseudomembranes of fibrin", "options": {"A": "Anti-Saccharomyces cerevisiae antibody positivity (ASCA)", "B": "Ascitic fluid infection", "C": "Pseudomembranes of fibrin", "D": "Increased osmotic load", "E": "Schistocytes on peripheral smear"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 9-year-old boy is brought to the physician for evaluation of a 3-day history of fever, sore throat, and itchy, red eyes. His symptoms began while he was away at summer camp. His immunizations are not up-to-date. He appears ill. His temperature is 39.1°C (102.3°F). Physical examination shows erythema and edema of the conjunctivae and posterior pharyngeal wall. There is bilateral, tender, preauricular lymphadenopathy. Further evaluation shows infection with a DNA virus. Which of the following is the most likely causal pathogen?", "answer": "Adenovirus", "options": {"A": "Adenovirus", "B": "Parvovirus", "C": "Picornavirus", "D": "Paramyxovirus", "E": "Human herpes virus 4"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 70-year-old man presents to the emergency department with severe substernal chest pain of one hour’s duration. The patient was taking a morning walk when the onset of pain led him to seek care. His past medical history includes coronary artery disease, hyperlipidemia, and hypertension. Medications include aspirin, losartan, and atorvastatin. An electrocardiogram reveals ST elevations in the inferior leads II, III, and avF as well as in leads V5 and V6. The ST elevations found in leads V5-V6 are most indicative of pathology in which of the following areas of the heart?", "answer": "Lateral wall of left ventricle, left circumflex coronary artery", "options": {"A": "Inferior wall, right coronary artery", "B": "Interventricular septum, left anterior descending coronary artery", "C": "Lateral wall of left ventricle, left circumflex coronary artery", "D": "Left atrium, left main coronary artery", "E": "Right ventricle, left main coronary artery"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old male visits his primary care physician after an episode of syncope during a tennis match. He reports exertional dyspnea with mild substernal chest pain. On physical exam a systolic crescendo-decrescendo murmur is heard best at the right 2nd intercostal space. This murmur was not heard at the patient's last appointment six months ago. Which of the following would most support a diagnosis of aortic stenosis?", "answer": "Murmur radiates to carotid arteries bilaterally", "options": {"A": "Presence of S3", "B": "Murmur radiates to carotid arteries bilaterally", "C": "Murmur radiates to axilla", "D": "Asymmetric ventricular hypertrophy", "E": "Double pulsation of the carotid pulse"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 37-year-old man presents to the physician. He has been overweight since childhood. He has not succeeded in losing weight despite following different diet and exercise programs over the past several years. He has had diabetes mellitus for 2 years and severe gastroesophageal reflux disease for 9 years. His medications include metformin, aspirin, and pantoprazole. His blood pressure is 142/94 mm Hg, pulse is 76/min, and respiratory rate is 14/min. His BMI is 36.5 kg/m2. Laboratory studies show:\nHemoglobin A1C 6.6%\nSerum  \nFasting glucose 132 mg/dL\nWhich of the following is the most appropriate surgical management?", "answer": "Laparoscopic Roux-en-Y gastric bypass", "options": {"A": "Biliopancreatic diversion and duodenal switch (BPD-DS)", "B": "Laparoscopic adjustable gastric banding", "C": "Laparoscopic Roux-en-Y gastric bypass", "D": "Laparoscopic sleeve gastrectomy", "E": "No surgical management at this time"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 8-year-old girl is brought to the emergency department because of a 2-day history of an intermittent, diffuse abdominal pain. She has also had a nonpruritic rash on her legs and swelling of her ankles for 1 week. Two weeks ago, she had a sore throat, which was treated with oral amoxicillin. Examination of the lower extremities shows non-blanching, raised erythematous papules. The ankle joints are swollen and warm, and their range of motion is limited by pain. Laboratory studies show a platelet count of 450,000/mm3. Test of the stool for occult blood is positive. Which of the following is the most likely diagnosis?", "answer": "Leukocytoclastic vasculitis", "options": {"A": "Immune thrombocytopenic purpura", "B": "Acute rheumatic fever", "C": "Juvenile idiopathic arthritis", "D": "Familial Mediterranean fever", "E": "Leukocytoclastic vasculitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old physician notices that her senior colleague has been arriving late for work for the past 2 weeks. The colleague recently lost his wife to cancer and has been taking care of his four young children. Following the death of his wife, the department chair offered him extended time off but he declined. There have been some recent changes noted in this colleague that have been discussed among the resident physicians, such as missed clinic appointments, two intra-operative errors, and the smell of alcohol on his breath on three different occasions. Which of the following is the most appropriate action by the physician regarding her colleague?", "answer": "Inform the local Physician Health Program", "options": {"A": "Contact the colleague's friends and family", "B": "Confront the colleague in private", "C": "Inform the local Physician Health Program", "D": "Inform the colleague's patients about the potential hazard", "E": "Alert the State Licensing Board"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old man presents for a follow-up appointment. He recently was found to have a history of stage 2 chronic kidney disease secondary to benign prostatic hyperplasia leading to urinary tract obstruction. He has no other medical conditions. His father died at age 86 from a stroke, and his mother lives in an assisted living facility. He smokes a pack of cigarettes a day and occasionally drinks alcohol. His vital signs include: blood pressure 130/75 mm Hg, pulse 75/min, respiratory rate 17/min, and temperature 36.5°C (97.7°F). His physical examination is unremarkable. A 24-hour urine specimen reveals the following findings:\nSpecific gravity 1,050\npH 5.6\nNitrites (-)\nGlucose (-)\nProteins 250 mg/24hrs\nWhich of the following should be prescribed to this patient to decrease his cardiovascular risk?", "answer": "Enalapril", "options": {"A": "Ezetimibe", "B": "Enalapril", "C": "Carvedilol", "D": "Aspirin", "E": "Amlodipine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old man comes to the physician because he and his wife have been unable to conceive despite regular unprotected sex for the past 15 months without using contraception. His wife has been tested and is fertile. The patient began puberty at the age of 14 years. He was treated for Chlamydia trachomatis 6 years ago. He is a professional cyclist and trains every day for 3–4 hours. He feels stressed because of an upcoming race. His blood pressure is 148/92 mm Hg. Physical examination of the husband shows a tall, athletic stature with uniform inflammatory papular eruptions of the face, back, and chest. Genital examination shows small testes. Which of the following is the most likely underlying cause of this patient's infertility?", "answer": "Anabolic steroid use", "options": {"A": "Psychogenic erectile dysfunction", "B": "Kallmann syndrome", "C": "Anabolic steroid use", "D": "Scrotal hyperthermia", "E": "Klinefelter syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-year-old male with a history of rhinitis presents to the emergency department with complaints of shortness of breath and wheezing over the past 2 days. He reports bilateral knee pain over the past month for which he recently began taking naproxen 1 week ago. Physical examination is significant for a nasal polyp and disappearance of bilateral radial pulses on deep inspiration. Which of the following is the most likely cause of this patient's physical examination findings?", "answer": "Asthma", "options": {"A": "Pulmonary hypertension", "B": "Interstitial lung fibrosis", "C": "Asthma", "D": "Pulmonary embolism", "E": "Cardiac tamponade"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old lifeguard develops squamous cell carcinoma of the skin on his forehead. Which of the following most likely preceded the development of this carcinoma?", "answer": "Dry, scaly, hyperkeratotic papule", "options": {"A": "Hamartomatous lesion of sebaceous glands", "B": "Dry, scaly, hyperkeratotic papule", "C": "A single, large pink patch", "D": "Dermatophyte infection", "E": "UVC exposure"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 29-year-old man is brought to the emergency department by his wife due to unusual behavior for the past week. She has noted several incidents when he spoke to her so fast that she could not understand what he was saying. She also says that one evening, he drove home naked after a night where he said he was ‘painting the town red’. She also says he has also been sleeping for about 2 hours a night and has barely had any sleep in the past 2 weeks. She says that he goes ‘to work’ in the morning every day, but she suspects that he has been doing other things. She denies any knowledge of similar symptoms in the past. On physical examination, the patient appears agitated and is pacing the exam room. He compliments the cleanliness of the floors, recommends the hospital change to the metric system, and asks if anyone else can hear ‘that ringing’. Laboratory results are unremarkable. The patient denies any suicidal or homicidal ideations. Which of the following is the most likely diagnosis in this patient?", "answer": "Bipolar disorder, type I", "options": {"A": "Major depressive disorder", "B": "Brief psychotic disorder", "C": "Schizoaffective disorder", "D": "Bipolar disorder, type I", "E": "Bipolar disorder, type II"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old man presents with a small painless ulcer with a raised border on his right forearm which has persisted for the last 3 weeks. His past history is significant for 3 occurrences of basal cell carcinoma on different areas of the body during the last 4 years, which have all been surgically excised. The morphology of the present lesion is also highly suggestive of basal cell carcinoma. The patient says that, if the lesion is a basal cell carcinoma, he does not want to undergo biopsy and surgery if it can be avoided. The patient is prescribed a cream, which is FDA-approved for the treatment of small superficial basal cell carcinomas in low-risk areas. The cream contains a chemotherapeutic agent, which is an antimetabolite and an S-phase-specific anticancer drug. Which of the following best explains the mechanism of action of this cream?", "answer": "Inhibition of thymidylate synthase", "options": {"A": "Inhibition of ribonucleotide reductase", "B": "Inhibition of DNA repair", "C": "Inhibition of thymidylate synthase", "D": "Inhibition of dihydrofolate reductase", "E": "Inhibition of de novo purine nucleotide synthesis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 29-year-old woman presents for a follow-up visit after an emergency appendectomy. The laparoscopic procedure went well with no complications. Physical examination reveals the surgical site is slightly tender but is healing appropriately. She is delighted that the operation went well and offers you a cake and VIP tickets to a musical concert. Which of the following is the most appropriate response?", "answer": "\"Thank you, but I cannot accept the tickets you offered. Accepting such a generous gift is against our policy. However, I will gladly accept your cake and distribute it among the staff.\"", "options": {"A": "\"Thank you, I will enjoy these gifts immensely.\"", "B": "\"No, I cannot accept these gifts, please take them with you as you leave.\"", "C": "\"May I pay you for them?\"", "D": "\"Thank you, but I cannot accept the tickets you offered. Accepting such a generous gift is against our policy. However, I will gladly accept your cake and distribute it among the staff.\"", "E": "\"Can you get another ticket for my friend?\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 62-year-old man presents to the emergency department with increased fatigue and changes in his vision. The patient states that for the past month he has felt abnormally tired, and today he noticed his vision was blurry. The patient also endorses increased sweating at night and new onset headaches. He states that he currently feels dizzy. The patient has a past medical history of diabetes and hypertension. His current medications include insulin, metformin, and lisinopril. His temperature is 99.5°F (37.5°C), blood pressure is 157/98 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Cardiopulmonary exam is within normal limits. HEENT exam reveals non-tender posterior and anterior chain lymphadenopathy. Abdominal exam reveals splenomegaly and hepatomegaly. There are large, non-tender palpable lymph nodes in the patient's inguinal region. Neurological exam is notable for decreased sensation in the patients hands and feet. He also complains of a numb/tingling pain in his extremities that has been persistent during this time. Dermatologic exam is notable for multiple bruises on his upper and lower extremities. Which of the following is most likely to be abnormal in this patient?", "answer": "IgM", "options": {"A": "Calcium", "B": "IgA and IgG", "C": "IgM", "D": "Natural killer cells", "E": "T-cells"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 42-year-old man presents to his primary care provider for a follow-up appointment after a new diagnosis of hypertension follow-up. The doctor mentions that a recent study where the effect of a healthy lifestyle education program on blood pressure was studied in 2 matched rural communities. One community received health education program and the other did not. What is the type of study most likely being described here?", "answer": "Community trial", "options": {"A": "Crossover study", "B": "Case-control trial", "C": "Explanatory study", "D": "Community trial", "E": "Cross-sectional study"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old female radiologist who is interviewing for a night shift position states that she was fired from her past 3 previous positions because she had difficulty working with others. She states that she is perfect for this job however, as she likes to work on her own and be left alone. She emphasizes that she does not have any distractions or meaningful relationships, and therefore she is always punctual and never calls in sick. She is not an emotional individual. Which of the following personality disorders best fits this female?", "answer": "Schizoid", "options": {"A": "Schizotypal", "B": "Schizoid", "C": "Antisocial", "D": "Borderline", "E": "Obsessive-compulsive disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 67-year-old female presents to her primary care physician complaining of headaches in her left temple and scalp area, neck stiffness, occasional blurred vision, and pain in her jaw when chewing. The appropriate medical therapy is initiated, and a subsequent biopsy of the temporal artery reveals arteritis. Five months later, the patient returns to her physician with a complaint of weakness, leading to difficulty climbing stairs, rising from a chair, and combing her hair. The patient states that this weakness has worsened gradually over the last 2 months. She reports that her headaches, jaw pain, and visual disturbances have resolved. Physical examination is significant for 4/5 strength for both hip flexion/extension as well as shoulder flexion/extension/abduction. Initial laboratory work-up reveals ESR and creatine kinase levels within normal limits. Which of the following is the most likely diagnosis in this patient's current presentation?", "answer": "Drug-induced myopathy", "options": {"A": "Mononeuritis multiplex", "B": "Polymyalgia rheumatica", "C": "Drug-induced myopathy", "D": "Polymyositis", "E": "Dermatomyositis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old man presents to the office complaining of abdominal pain. He was started on a trial of proton pump inhibitors 5 weeks ago but the pain has not improved. He describes the pain as dull, cramping, and worse during meals. Medical history is unremarkable. Physical examination is normal except for tenderness in the epigastric region. Endoscopy reveals an eroding gastric ulcer in the proximal part of the greater curvature of the stomach overlying a large pulsing artery. Which of the following arteries is most likely visible?", "answer": "Left gastro-omental artery", "options": {"A": "Common hepatic artery", "B": "Left gastric artery", "C": "Right gastro-omental artery", "D": "Left gastro-omental artery", "E": "Cystic artery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A mother brings her 2-year-old son to the pediatrician following an episode of abdominal pain and bloody stool. The child has otherwise been healthy and growing normally. On physical exam, the patient is irritable with guarding of the right lower quadrant of the abdomen. Based on clinical suspicion, pertechnetate scintigraphy demonstrates increased uptake in the right lower abdomen. Which of the following embryologic structures is associated with this patient’s condition?", "answer": "Vitelline duct", "options": {"A": "Metanephric mesenchyme", "B": "Ductus arteriosus", "C": "Vitelline duct", "D": "Paramesonephric duct", "E": "Allantois"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 59-year-old patient comes to the emergency department accompanied by his wife because of severe right leg pain and numbness. His condition suddenly started an hour ago. His wife says that he has a heart rhythm problem for which he takes a blood thinner, but he is not compliant with his medications. He has smoked 10–15 cigarettes daily for the past 15 years. His temperature is 36.9°C (98.42°F), blood pressure is 140/90 mm Hg, and pulse is 85/min and irregular. On physical examination, the patient is anxious and his right leg is cool and pale. Palpation of the popliteal fossa shows a weaker popliteal pulse on the right side compared to the left side. Which of the following is the best initial step in the management of this patient's condition?", "answer": "Urgent assessment for amputation or revascularization", "options": {"A": "Cilostazol", "B": "Decompressive laminectomy", "C": "Urgent assessment for amputation or revascularization", "D": "Oral acetaminophen and topical capsaicin", "E": "Arthroscopic synovectomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 12-year-old girl is brought to the pediatrician by her father who is concerned about the child’s ability to sit in a moving vehicle. She frequently develops nausea and dizziness when riding in a car for more than 10 minutes. The child has vomited twice over the past month while riding in the car. Her symptoms are significantly impairing her ability to make it to school on time without having to stop and get out of the car. The child does well in school and has several close friends. On examination, the child is well-appearing and appropriately interactive. Dix-Hallpike maneuver is negative. Her gait is normal. Strength and range of motion are full and symmetric bilaterally in the upper and lower extremities. The father would like to know if there is anything his daughter can take to be able to sit in a moving vehicle without feeling ill. A medication with which of the following mechanisms of action is indicated to manage this patient’s symptoms?", "answer": "Muscarinic acetylcholine receptor antagonist", "options": {"A": "Alpha-2 adrenergic receptor agonist", "B": "Beta-1 adrenergic receptor agonist", "C": "Muscarinic acetylcholine receptor agonist", "D": "Muscarinic acetylcholine receptor antagonist", "E": "Nicotinic acetylcholine receptor agonist"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old female suffering from a urinary tract infection is given trimethoprim-sulfamethoxazole (TMP-SMX) by her physician. Several days later, she begins to experience itchiness and joint pain. Laboratory and histologic analysis reveals vasculitis and antibody complexes deposited near the basement membrane of the glomerulus. What other serological finding is expected with this presentation?", "answer": "Lowered serum levels of complement protein C3", "options": {"A": "Decreased levels of IgE", "B": "Increased levels of IgE", "C": "Decreased neutrophil count", "D": "Increased serum levels of complement protein C3", "E": "Lowered serum levels of complement protein C3"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old woman presents to your office complaining of difficulty swallowing, and she describes that \"there is something in the back of her throat\". Furthermore, she also feels an \"achy\" chest pain that has been getting progressively worse over the last few weeks. She denies having any fever, shortness of breath, cough, abdominal pain, heartburn, nausea, or vomiting. The patient has a history of wrist fracture as a child, migraines, and a recent diagnosis of myasthenia gravis. Which of the following is the most likely diagnosis?", "answer": "Benign tumor of the thymus", "options": {"A": "Benign tumor of the thymus", "B": "Superior vena cava syndrome", "C": "Anaplastic thyroid cancer", "D": "Mediastinitis", "E": "Thyroglossal duct cyst"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old woman comes to the physician for a follow-up appointment because of a blood pressure of 148/98 mm Hg at her last health maintenance examination four weeks ago. She feels well. She has a 20-year history of migraine with aura of moderate to severe intensity. For the past year, the headaches have been occurring 1–2 times per week. Her only medication is sumatriptan. She runs two to three times a week and does yoga once a week. She is sexually active with her husband and uses condoms inconsistently. Her father has type 2 diabetes mellitus and hypertension. Her temperature is 37.2°C (99.0°F), pulse is 76/min, respirations are 12/min, and blood pressure is 143/92 mm Hg. A repeat sitting blood pressure 20 minutes later is 145/94 mm Hg. Physical examination is unremarkable. Which of the following is the most appropriate pharmacotherapy for this patient?", "answer": "Propranolol", "options": {"A": "Hydrochlorothiazide", "B": "Lisinopril", "C": "Propranolol", "D": "Losartan", "E": "Prazosin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A mother brings her 25-month-old son to the pediatrician’s office for a well child visit. She reports he had an ear infection 3 months ago for which he took a short course of antibiotics but has otherwise been well. He is now in daycare where he likes to play with the other children. She says he can stack multiple cubes and enjoys playing with objects. He goes outside frequently to play with a ball and is able to kick it. While talking to the mother, the patient and his sister draw on paper quietly side by side. His mother says he knows about 200 words and he frequently likes to use “I” sentences, like “I read” and “I drink”. His mother does complain that he throws more tantrums than he used to and she has found it harder to get him to follow instructions, although he appears to understand them. Which of the following milestones is delayed in this child?", "answer": "None", "options": {"A": "Gross motor", "B": "Fine motor", "C": "Language", "D": "Social development", "E": "None"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old man is brought to the emergency department 25 minutes after he was found shaking violently on the bathroom floor. His wife reports that he has become increasingly confused over the past 2 days and that he has been sleeping more than usual. He was started on chemotherapy 4 months ago for chronic lymphocytic leukemia. He is confused and oriented to person only. Neurological examination shows right-sided ptosis and diffuse hyperreflexia. An MRI of the brain shows disseminated, nonenhancing white matter lesions with no mass effect. A polymerase chain reaction assay of the cerebrospinal fluid confirms infection with a virus that has double-stranded, circular DNA. An antineoplastic drug with which of the following mechanisms of action is most likely responsible for this patient's current condition?", "answer": "Monoclonal antibody against CD20+", "options": {"A": "Free radical formation", "B": "Tyrosine kinase inhibitor", "C": "Topoisomerase II inhibitor", "D": "Monoclonal antibody against EGFR", "E": "Monoclonal antibody against CD20+"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman presents to her primary care provider complaining of lower back pain. She reports a 3 day history of extreme right lower back pain. She also reports mild dysuria. Her past medical history is notable for recurrent urinary tract infections leading to 3 emergency room visits over the past year. Her family history is notable for renal cell carcinoma in her paternal grandfather and diabetes in her father. Her temperature is 99.5°F (37.5°C), blood pressure is 125/75 mmHg, pulse is 82/min, and respirations are 18/min. On exam, she has mild right costovertebral angle tenderness. Radiography demonstrates a vague radiopaque structure in the right lower abdomen. Results of a urinalysis are shown below:\n\nAppearance: Hazy, yellow\nProtein: Negative\nSpecific gravity: 1.029\nWBC: 2+\nCasts: None\nBacteria: None\npH: 8.9\nBlood: Negative\nBilirubin: Negative\nUrobilinogen: < 2.0\n\nA urine culture is pending. Which of the following pathogens is most likely responsible for this patient’s condition?", "answer": "Proteus mirabilis", "options": {"A": "Escherichia coli", "B": "Enterococcus", "C": "Citrobacter freundii", "D": "Proteus mirabilis", "E": "Staphylococcus epidermidis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 8-month-old boy is brought to the emergency room by his mother who notes that the child has not been passing stool regularly. Palpation and radiographic imaging of the umbilical region reveal the presence of fecal material in an abnormal out-pocketing of bowel. Which of the following is a common complication seen in this condition?", "answer": "Ulceration", "options": {"A": "Enlarged rugal folds", "B": "Dysplasia", "C": "Ulceration", "D": "Megacolon", "E": "Paneth cell metaplasia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 69-year-old woman is brought to the clinic for difficulty breathing over the past 2 months. She denies any clear precipitating factor but reports that her breathing has become progressively labored and she feels like she can’t breathe. Her past medical history is significant for heart failure, diabetes mellitus, and hypertension. Her medications include lisinopril, metoprolol, and metformin. She is allergic to sulfa drugs and peanuts. A physical examination demonstrates bilateral rales at the lung bases, pitting edema of the lower extremities, and a laterally displaced point of maximal impulse (PMI). She is subsequently given a medication that will reduce her volume status by competitively binding to aldosterone receptors. What is the most likely drug prescribed to this patient?", "answer": "Spironolactone", "options": {"A": "Amiloride", "B": "Atorvastatin", "C": "Furosemide", "D": "Hydrochlorothiazide", "E": "Spironolactone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 80-year-old woman presents with general malaise and low-grade fever. Physical examination reveals several retinal hemorrhages with pale centers, erythematous nodules on palms that are not painful, and splinter hemorrhages under her fingernails. Echocardiogram shows vegetations on the mitral valve. Blood culture indicates gram-positive bacteria which are catalase negative and able to grow in 40% bile; however, not in 6.5% NaCl. In addition to endocarditis, the doctor is concerned that the patient may also be suffering from which of the following medical conditions?", "answer": "Colon cancer", "options": {"A": "Subacute sclerosing panencephalitis", "B": "Sickle cell disease", "C": "Dental caries", "D": "HIV/AIDS", "E": "Colon cancer"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 63-year-old man presents to the physician with fever for 5 days. He has had increasing fatigue and dyspnea for the past 2 months. During this time, he has lost 3 kg (6.6 lb). He received outpatient treatment for pneumonia last month. He had urinary tract infection 2 weeks ago. He takes no other medications other than daily low dose aspirin and recent oral antibiotics. He does not smoke or drink alcohol. The vital signs include: temperature 38.5°C (101.3°F), pulse 93/min, respiration rate 18/min, and blood pressure 110/65 mm Hg. On physical examination, he has petechiae distally on the lower extremities and several purpura on the trunk and extremities. Several enlarged lymph nodes are detected in the axillary and cervical regions on both sides. The examination of the lungs, heart, and abdomen shows no abnormalities. The laboratory test results are as follows:\nHemoglobin 10 g/dL\nMean corpuscular volume 90 μm3\nLeukocyte count 18,000/mm3\nPlatelet count 40,000/mm3\nA Giemsa-stained peripheral blood smear is shown by the image. Which of the following is the most likely diagnosis?", "answer": "Acute myeloblastic leukemia", "options": {"A": "Acute myeloblastic leukemia", "B": "Burkitt lymphoma", "C": "Hairy cell leukemia", "D": "Hodgkin’s lymphoma", "E": "MALT lymphoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 9-year-old girl is brought to her pediatrician by her mother for the evaluation of recent-onset seizures. She has had 2 episodes of generalized tonic-clonic seizures in the past 3 days. Each episode lasted for 1–2 minutes and aborted spontaneously. There is no history of fever, headache, altered behavior, diarrhea, vomiting, or previous seizure episodes. Past medical history is unremarkable. Physical examination reveals: blood pressure 102/64 mm Hg, heart rate 89/min, respiratory rate 16/min, and temperature 37.0°C (98.6°F). She looks anxious but oriented to time and space. Multiple flat hyperpigmented spots are present over her body, each more than 5 mm in diameter. Axillary freckling is present. Cranial nerves are intact. Muscle strength is normal in all 4 limbs with a normal sensory examination. Gait is normal. An eye examination is shown in the exhibit. What is the most likely diagnosis?", "answer": "Von Recklinghausen disease", "options": {"A": "Neurofibromatosis type 2", "B": "Sturge-Weber disease", "C": "Tuberous sclerosis", "D": "Von Recklinghausen disease", "E": "Wilson disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to the emergency department by his parents. They state that he has had trouble walking the past day and this morning refuses to walk at all. The child has a past medical history of asthma, which is treated with albuterol. His temperature is 102°F (38.9°C), blood pressure is 77/48 mmHg, pulse is 150/min, respirations are 17/min, and oxygen saturation is 98% on room air. Laboratory tests are drawn and shown below.\n\nHemoglobin: 10 g/dL\nHematocrit: 36%\nLeukocyte count: 13,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\n\nAn MRI of the the thigh and knee is performed and demonstrates edema and cortical destruction of the distal femur. Which of the following is the most likely infectious agent in this patient?", "answer": "Staphylococcus aureus", "options": {"A": "Bacteroides species", "B": "Pseudomonas aeruginosa", "C": "Salmonella species", "D": "Staphylococcus aureus", "E": "Staphylococcus epidermidis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old man presents to his family practitioner for routine follow-up of asthma. He is currently on albuterol, corticosteroids, and salmeterol, all via inhalation. The patient is compliant with his medications, but he still complains of episodic shortness of breath and wheezing. The peak expiratory flow (PEF) has improved since the last visit, but it is still less than the ideal predicted values based on age, gender, and height. Montelukast is added to his treatment regimen. What is the mechanism of action of this drug?", "answer": "Montelukast blocks receptors of some arachidonic acid metabolites.", "options": {"A": "Montelukast inhibits the release of inflammatory substances from mast cells.", "B": "Montelukast binds to IgE.", "C": "Montelukast activates adrenal receptors on the bronchial smooth muscles.", "D": "Montelukast blocks receptors of some arachidonic acid metabolites.", "E": "Montelukast inhibits lipoxygenase, thus decreasing the production of inflammatory leukotrienes."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old medical student is doing an international health elective in the Amazon River basin studying tropical disease epidemiology. As part of his pre-trip preparation, he wants to be protected from malaria and is researching options for prophylaxis. Which of the following agents should be avoided for malarial prophylaxis in this patient?", "answer": "Chloroquine", "options": {"A": "Chloroquine", "B": "Mefloquine", "C": "Atovaquone-proguanil", "D": "Doxycycline", "E": "Quinine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old woman presents complaining of nightmares. She reports that these “nightmares” happen when she is asleep and also sometimes when she is awake, but she cannot come up with another description for them. The episodes have been happening for at least 3 weeks now. She states that when it happens she feels “outside of her body,” like she’s “watching myself.” She also reports some chronic fatigue. The patient denies headaches, vision changes, dizziness, or loss in sensation or motor function. She has no notable medical or surgical history. She takes a multivitamin every day. She smokes 1 pack of cigarettes a day but denies alcohol or illicit drug use. The patient appears slightly anxious but is in no acute distress. A physical and neurological exam is normal. She denies suicidal or homicidal ideation. Which of the following is the most likely diagnosis for the patient’s symptoms?", "answer": "Depersonalization disorder", "options": {"A": "Brief psychotic disorder", "B": "Delusional disorder", "C": "Depersonalization disorder", "D": "Dissociative fugue disorder", "E": "Dissociative identity disorder"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old woman comes to the physician for a 6-week history of sleeping difficulties because she thinks that someone is watching her through security cameras. Her anxiety started 6 weeks ago when a security camera was installed outside her house by the police. Ever since, she has felt that she is being monitored by security cameras throughout the city. She avoids going outside whenever possible and refuses to take the subway. Whenever she needs to leave the house she wears large hats or hooded sweaters so that she cannot be recognized by the cameras. As soon as she arrives at her office or at home she feels safer. She was recently promoted to the team manager of a small advertising agency. She takes no medications. On mental status examination, she is alert, oriented, and shows normal range of affect. Urine toxicology screening is negative. The patient's symptoms are best described as which of the following?", "answer": "Delusions", "options": {"A": "Agoraphobia", "B": "Delusions", "C": "Derealization", "D": "Disorganized thoughts", "E": "Hallucinations"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 49-year-old man with alcohol use disorder is brought to the emergency department immediately after two episodes of coffee-ground emesis. His pulse is 116/min and blood pressure is 92/54 mm Hg. Physical examination shows a distended abdomen with shifting dullness. Skin examination shows jaundice, erythematous palms, and dilated veins in the anterior abdominal wall. After fluid resuscitation, he is given a drug that decreases portal venous pressure. The drug works by inhibiting the secretion of splanchnic vasodilatory hormones as well as blocking glucagon and insulin release. This drug is a synthetic analog of a substance normally produced in which of the following cells?", "answer": "D cells", "options": {"A": "S cells", "B": "G cells", "C": "K cells", "D": "D cells", "E": "I cells\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old college student is brought to the emergency department by his roommates after being found unconscious on their dorm room floor. His temperature is 102.0°F (38.9°C) and blood pressure is 85/64 mmHg. On physical examination, he has multiple rose-colored spots on the skin covering his abdomen and lower limbs. Lab tests reveal hyperkalemia and an arterial blood gas test that reads pH: 7.04, pCO2: 30.1 mmHg, pO2: 23.4 mmHg. What is the most likely diagnosis for this patient’s condition?", "answer": "Waterhouse-Friderichsen syndrome", "options": {"A": "Addison disease", "B": "Dengue hemorrhagic fever", "C": "Diabetic ketoacidosis", "D": "Typhoid fever", "E": "Waterhouse-Friderichsen syndrome"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 39-year-old man with a history of major depression is brought into the emergency department by his concerned daughter. She reports that he was recently let go from work because of his sudden and erratic behavior at work. He was noted to be making inappropriate sexual advances to his female co-workers which is very out of his character. He seemed to be full of energy, running on little to no sleep, trying to fix all the companies problems and at times arguing with some of the senior managers. During admission, he was uninterpretable as he boasted about how he was right and that the managers were fools for not listening to his great ideas. What treatment options are available for this patient?", "answer": "Mood stabilizers, antipsychotics, benzodiazepines, ECT", "options": {"A": "Mood stabilizers, antipsychotics, benzodiazepines, ECT", "B": "Mood stabilizers, antipsychotics", "C": "Antipsychotics", "D": "Benzodiazepines", "E": "ECT"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman, gravida 2, para 1, at 33 weeks’ gestation, is admitted to the hospital for treatment of preterm labor. She has no history of serious illness and her only medication is a multivitamin. Her temperature is 37.2°C (99.0°F), pulse is 100/min, respirations are 20/min, and blood pressure is 100/75 mm Hg. Therapy with nifedipine and betamethasone is begun. The patient continues to have contractions; nifedipine is discontinued and treatment with high-dose terbutaline is initiated. Her contractions resolve. Three hours later, the patient reports fatigue and weakness. Neurologic examination shows proximal muscle weakness of the lower extremities. Deep tendon reflexes are 1+ bilaterally. Which of the following is most likely to confirm the diagnosis?", "answer": "Serum electrolytes", "options": {"A": "Serum electrolytes", "B": "Complete blood count", "C": "Serologic antibody testing", "D": "Amniotic fluid culture", "E": "Thyroid function tests"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 70-year-old male patient comes into your office because of leg pain. The patient states that his calves have been hurting more and more over the last two months. The pain isn't present at rest, but the pain develops as the patient starts walking and exerting himself. He states that stopping to rest is the only thing that relieves the pain. Of note, the patient's medical history is significant for 30-pack-years of smoking, hypertension, hyperlipidemia, and a previous myocardial infarction status-post angioplasty and stent. On exam, the patient's lower legs (below knee) have glossy skin with loss of hair. The dorsalis pedis pulses are barely palpable bilaterally. Which of the following is the best initial therapy for this patient?", "answer": "Lifestyle modifications", "options": {"A": "Lifestyle modifications", "B": "Cilostazol", "C": "Clopidogrel", "D": "Angioplasty and stenting", "E": "Arterial bypass surgery"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old man comes to the physician because of a 1-week history of muscle ache, fatigue, and fever that occurs every 2 days. He recently returned from a trip to Myanmar. A peripheral blood smear shows erythrocytes with brick-red granules. The physician recommends a combination of two antimicrobial drugs after confirming normal glucose-6-phosphate dehydrogenase activity. Which of the following is the most appropriate rationale for dual therapy?", "answer": "Prevention of infection relapse", "options": {"A": "Prevention of infection relapse", "B": "Therapy against polymicrobial infections", "C": "Prevention of drug resistance", "D": "Decrease in renal drug secretion", "E": "Decrease in enzymatic drug deactivation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old woman is brought to the emergency department by her parents after finding her seizing in her room at home. She has no known medical condition and this is her first witnessed seizure. She is stabilized in the emergency department. A detailed history reveals that the patient has been progressively calorie restricting for the past few years. Based on her last known height and weight, her body mass index (BMI) is 16.5 kg/m2. Which of the following electrolyte abnormalities would be of the most concern when this patient is reintroduced to food?", "answer": "Hypophosphatemia", "options": {"A": "Hypophosphatemia", "B": "Hypercalcemia", "C": "Hypermagnesemia", "D": "Hyponatremia", "E": "Hypokalemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old woman, gravida 3, para 1, at 22 weeks gestation visits her physician for a prenatal visit. She feels well. Her current pregnancy has been uncomplicated. She has attended many prenatal appointments and followed the physician's advice about screening for diseases, laboratory testing, diet, and exercise. The patient’s previous pregnancies were complicated by preterm labor at 24 weeks gestation in one pregnancy and spontanious abortion at 22 weeks in the other. She takes a multivitamin with folate every day. At the physician’s office, her temperature is 37.2°C (99.0°F), and blood pressure is 109/61 mm Hg. Pelvic examination shows a uterus consistent in size with a 20-week gestation. Fetal heart sounds are normal. An ultrasound shows a short cervix, measured at 20 mm. Which of the following is the most appropriate next step in management?", "answer": "Cerclage", "options": {"A": "Cerclage", "B": "Cervical pessary", "C": "Intramuscular progesterone", "D": "Intravenous betamethasone", "E": "Vaginal progesterone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old female presents to the emergency department complaining of a worsening headache. The patient reports that the headache started one month ago. It is constant and “all over” but gets worse when she is lying down or in the setting of bright lights. Review of systems is significant for low-grade fever, night sweats, cough, malaise, poor appetite, and unintentional weight loss of 12 pounds in the last two months. The patient is sexually active with multiple male partners and reports inconsistent condom use. She has a history of intravenous drug use, and has not been to a doctor in the last two years. The patient’s temperature is 100.4°F (38.0°C), blood pressure is 110/78 mmHg, pulse is 88/min, and respirations are 14/min with an oxygen saturation of 98% O2 on room air. On physical exam, pain is elicited upon passive flexion of the patient’s neck. A CT scan shows ventricular enlargement. A CD4+ count is 57 cells/µL blood. A lumbar puncture is performed with the following findings:\n\nCerebrospinal fluid:\nOpening pressure: 210 mmH2O\nGlucose: 32 mg/dL\nProtein: 204 mg/dL\nIndia ink stain: Positive\n\nLeukocyte count and differential:\nLeukocyte count: 200/mm^3\nLymphocytes: 100%\nRed blood cell count: 2\n\nWhat is the next best step in therapy?", "answer": "Administer amphotericin B and 5-flucytosine", "options": {"A": "Administer fluconazole", "B": "Administer amphotericin B and 5-flucytosine", "C": "Administer vancomycin and ceftriaxone", "D": "Administer acyclovir", "E": "Administer dexamethasone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 67-year-old man is brought to the emergency department by his wife due to dizziness, trouble with walking, and progressively worsening headache. These symptoms began approximately two hours prior to arriving to the hospital and were associated with nausea and one episode of vomiting. Medical history is significant for hypertension, hypercholesterolemia, and type II diabetes mellitus, which is managed with lisinopril, atorvastatin, and metformin. His temperature is 99°F (37.2°C), blood pressure is 182/106 mmHg, pulse is 102/min, and respirations are 20/min. On physical examination, the patient has right-sided dysmetria on finger-to-nose testing and right-sided dysrhythmia on rapid finger tapping. This patient's abnormal physical exam findings is best explained by decreased neuronal input into which of the following nuclei?", "answer": "Dentate and interposed nuclei", "options": {"A": "Dentate and vestibular nuclei", "B": "Eboliform and fastigial nuclei", "C": "Dentate and interposed nuclei", "D": "Fastigial and globose nuclei", "E": "Vestibular and eboliform nuclei"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old woman presents with fatigue and pain of the proximal interphalangeal and metacarpophalangeal joints for the past 6 months. She also has knee and wrist pain that has been present for the past 2 months, with morning stiffness that improves over the course of the day. Physical examination is significant for subcutaneous nodules. Laboratory tests are significant for the following:\nHemoglobin 12.5 g/dL\nRed blood cell count 4.9 x 106/µL\nWhite blood cell count 5,000/mm3\nPlatelet count 180,000/mm3\nCoombs' test Negative\nC-reactive peptide (CRP) Elevated\nErythrocyte sedimentation rate (ESR) Negative\nAnti-cyclic citrullinated peptide antibody (anti-CCP antibody) Moderately positive\nAnti-nuclear antibody (ANA) Negative\nRheumatoid factor (RF) Negative\nWhat is the most likely human leukocyte antigen (HLA) subtype associated with this disease?", "answer": "HLA-DR4", "options": {"A": "HLA-DR4", "B": "HLA-DR2", "C": "HLA-DR5", "D": "HLA-DQ2", "E": "HLA-B27"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman presents to the emergency department for sudden, bilateral, painful loss of vision. She states that her symptoms started last night and have persisted until this morning. The patient has a past medical history of peripheral neuropathy which is currently treated with duloxetine and severe anxiety. Her temperature is 99.5°F (37.5°C), blood pressure is 100/60 mmHg, pulse is 100/min, respirations are 15/min, and oxygen saturation is 98% on room air. On physical exam, the patient demonstrates 4/5 strength in her upper and lower extremities with decreased sensation in her fingers bilaterally. Towards the end of the exam, the patient embarrassingly admits to having an episode of urinary incontinence the previous night. An MRI is obtained and is within normal limits. Which of the following is the best next step in management and most likely finding for this patient?", "answer": "A lumbar puncture demonstrating oligoclonal bands", "options": {"A": "A repeat MRI 3 days later demonstrating periventricular lesions", "B": "A high resolution CT demonstrating hyperdense lesions", "C": "A lumbar puncture demonstrating oligoclonal bands", "D": "Urine toxicology panel demonstrating cocaine use", "E": "A psychiatric evaluation revealing multiple acute life stressors"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 36-year-old woman is fasting prior to a religious ceremony. Her only oral intake in the last 36 hours has been small amounts of water. The metabolic enzyme that is primarily responsible for maintaining normal blood glucose in this patient is located exclusively within the mitochondria. An increase in which of the following substances is most likely to increase the activity of this enzyme?", "answer": "Acetyl coenzyme A", "options": {"A": "Adenosine monophosphate", "B": "Glucagon", "C": "Oxidized nicotinamide adenine dinucleotide", "D": "Citrate", "E": "Acetyl coenzyme A"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 8-year-old boy is brought to the emergency department 3 hours after being bitten by his neighbor's dog. He was chasing the dog with a stick when it attacked him. He has fed the dog on multiple occasions and it has never bitten him before. His father saw the dog 2 hours after the incident and its behavior seemed normal. There is no personal or family history of serious illness in the family. The last vaccination the boy received was against varicella 2 years ago; he has never been immunized against rabies. He is not in acute distress. Vital signs are within normal limits. Examination shows a 2 cm (0.8 in) puncture wound on his left calf; there is minimal erythema around the wound. The remainder of the examination shows no abnormalities. A complete blood count is within the reference range. The wound is irrigated and washed with saline and chlorhexidine solution. Which of the following is the most appropriate next step in management?", "answer": "Observe the dog for 10 days", "options": {"A": "Observe the dog for 10 days", "B": "Euthanize the dog and test for rabies", "C": "Administer rabies vaccine and immune globulin", "D": "Administer rabies immune globulin", "E": "Administer rabies vaccine\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-year-old Caucasian male is brought to his pediatrician by his parents, who note the development of a tremor in their child. Urine and serum analysis reveal elevated levels of copper. Which of the following clinical manifestations would the physician most expect to see in this patient?", "answer": "Kaiser-Fleischer rings", "options": {"A": "Diabetes mellitus", "B": "Kaiser-Fleischer rings", "C": "Panacinar emphysema", "D": "Increased serum ceruloplasmin", "E": "Hepatocytes that stain with Prussian blue"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old man is brought to the emergency department by his son after collapsing to the ground while at home. His son immediately performed cardiopulmonary resuscitation and later the patient underwent successful defibrillation after being evaluated by the emergency medical technician. The patient has a medical history of hypertension, hyperlipidemia, and type II diabetes mellitus. He has smoked one-half pack of cigarettes for approximately 30 years. The patient was admitted to the cardiac intensive care unit, and after a few days developed acute onset right upper extremity weakness. His temperature is 99°F (37.2°C), blood pressure is 145/91 mmHg, pulse is 102/min and irregularly irregular, and respirations are 16/min. On physical examination, the patient is alert and orientated to person, place, and time. His language is fluent and he is able to name, repeat, and read. His strength is 5/5 throughout except in the right hand, wrist, and arm, which is 2/5. Based on this patient's clinical presentation, the affected neuronal fibers decussate at which level of the central nervous system?", "answer": "Caudal medulla", "options": {"A": "Primary motor cortex", "B": "Thalamus", "C": "Pons", "D": "Caudal medulla", "E": "Spinal cord"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old woman comes to the emergency department 1 hour after her husband saw her faint shortly after getting out of bed from a nap. She regained consciousness within 30 seconds and was fully alert and oriented. She has had 2 similar episodes in the last 5 years, once while standing in line at the grocery store and once when getting out of bed in the morning. 24-hour Holter monitoring and echocardiography were unremarkable at her last hospitalization 1 year ago. She has hypertension, depression, and asthma. Current medications include verapamil, nortriptyline, and an albuterol inhaler as needed. Her temperature is 37°C (98.4°F), pulse is 74/min and regular, respirations are 14/min, blood pressure is 114/72 mm Hg when supine and 95/60 mm Hg while standing. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. A complete blood count and serum concentrations of electrolytes, urea nitrogen, creatinine, and glucose are within the reference range. Bedside cardiac monitoring shows rare premature ventricular contractions and T-wave inversions in lead III. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Autonomic dysfunction", "options": {"A": "Adrenal insufficiency", "B": "Autonomic dysfunction", "C": "Structural cardiac abnormality", "D": "Hemorrhagic blood loss", "E": "Cardiac arrhythmia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old executive travels frequently around the world. He often has difficulty falling asleep at night when he returns home. You suspect a circadian rhythm disorder is responsible for his pathology. Which of the following regulates the circadian rhythm?", "answer": "Suprachiasmatic nucleus of hypothalamus", "options": {"A": "Anterior hypothalamus", "B": "Posterior hypothalamus", "C": "Ventromedial area of hypothalamus", "D": "Supraoptic area of hypothalamus", "E": "Suprachiasmatic nucleus of hypothalamus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old male presents to his pediatrician concerned that he is not maturing like his friends. He has a history of cleft palate status-post multiple surgeries and asthma treated with budesonide and albuterol. He is a good student and is very active on his school’s gymnastics team. His mother is also concerned that her son does not understand good personal hygiene. She reports that he always forgets to put on deodorant. When asked about this, he says he does not notice any body odor on himself or others. His temperature is 99.2°F (37.3°C), blood pressure is 105/70 mmHg, pulse is 70/min, and respirations are 18/min. His height and weight are in the 20th and 25th percentiles, respectively. On physical examination, his penis and testicles show no evidence of enlargement. He has no pubic or axillary hair. Which of the following sets of hormone levels is most likely to be found in this patient?", "answer": "Decreased testosterone, decreased FSH, decreased LH, decreased GnRH", "options": {"A": "Decreased testosterone, decreased FSH, decreased LH, decreased GnRH", "B": "Increased testosterone, decreased FSH, decreased LH, decreased GnRH", "C": "Decreased testosterone, increased FSH, increased LH, increased GnRH", "D": "Decreased testosterone, decreased FSH, decreased LH, increased GnRH", "E": "Normal testosterone, normal FSH, normal LH, normal GnRH"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 26-year-old primigravid woman at 10 weeks' gestation comes to the physician for a prenatal visit. Pregnancy was confirmed by an ultrasound 3 weeks earlier after the patient presented with severe nausea and vomiting. The nausea and vomiting have subsided without medication. She has no vaginal bleeding or discharge. Vital signs are within normal limits. Pelvic examination shows a uterus consistent in size with a 10-week gestation. Transvaginal ultrasonography shows a gestational sac with a mean diameter of 23 mm and an embryo 6 mm in length with absent cardiac activity. Which of the following is the most appropriate next step in management?", "answer": "Misoprostol therapy", "options": {"A": "Serial β-HCG measurements", "B": "Misoprostol therapy", "C": "Cervical cerclage", "D": "Thrombophilia work-up", "E": "Methotrexate therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 67-year-old man is brought to the emergency department when he was found obtunded at the homeless shelter. The patient is currently not responsive and smells of alcohol. The patient has a past medical history of alcohol use, IV drug use, and hepatitis C. His temperature is 99°F (37.2°C), blood pressure is 95/65 mmHg, pulse is 95/min, respirations are 13/min, and oxygen saturation is 95% on room air. The patient is started on IV fluids, and his pulse decreases to 70/min. On physical exam, the patient has an abdominal exam notable for distension and a positive fluid wave. The patient displays mild yellow discoloration of his skin. The patient has notable poor dentition and poor hygiene overall. A systolic murmur is heard along the left sternal border on cardiac exam. Pulmonary exam is notable for mild bibasilar crackles. Laboratory values are ordered, and return as below:\n\nHemoglobin: 10 g/dL\nHematocrit: 32%\nLeukocyte count: 7,500 cells/mm^3 with normal differential\nPlatelet count: 227,000/mm^3\n\nSerum:\nNa+: 125 mEq/L\nCl-: 100 mEq/L\nK+: 5.0 mEq/L\nHCO3-: 24 mEq/L\nBUN: 51 mg/dL\nGlucose: 89 mg/dL\nCreatinine: 2.2 mg/dL\nCa2+: 10.0 mg/dL\nAST: 22 U/L\nALT: 19 U/L\n\nUrine:\nColor: Amber\nNitrites: Negative\nSodium: 12 mmol/24 hours\nRed blood cells: 0/hpf\n\nOver the next 24 hours, the patient produces very little urine. Which of the following best explains this patient’s renal findings?", "answer": "Liver failure", "options": {"A": "Congestive heart failure", "B": "Dehydration", "C": "Liver failure", "D": "Nephrotoxic agent", "E": "Postrenal azotemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Two days after spontaneous delivery, a 23-year-old woman has progressively worsening, throbbing pain in the back of her head. The pain radiates to the neck and shoulder area. The patient is nauseous and had one episode of clear emesis. She wants to be in a dark and quiet room. The patient's symptoms are exacerbated when she gets up to go to the bathroom and mildly improve with bed rest. The pregnancy was uncomplicated and she attended all prenatal health visits. She underwent epidural analgesia for delivery with adequate pain relief. Her postpartum course was free of obstetric complications. Her vital signs are within normal limits. She is alert and oriented. On examination, neck stiffness is present. Neurological examination shows no other abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Epidural blood injection", "options": {"A": "Head CT angiography", "B": "Send coagulation panel", "C": "Cerebrospinal fluid analysis", "D": "Continued bed rest", "E": "Epidural blood injection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old man presents to the emergency department with persistent cough. The patient states that for the past week he has been coughing. He also states that he has seen blood in his sputum and experienced shortness of breath. On review of systems, the patient endorses fever and chills as well as joint pain. His temperature is 102°F (38.9°C), blood pressure is 159/98 mmHg, pulse is 80/min, respirations are 14/min, and oxygen saturation is 98% on room air. Laboratory values are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 7,500/mm^3 with normal differential\nPlatelet count: 107,000/mm^3\n\nSerum:\nNa+: 138 mEq/L\nCl-: 101 mEq/L\nK+: 4.2 mEq/L\nHCO3-: 24 mEq/L\nBUN: 32 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.9 mg/dL\nCa2+: 10.0 mg/dL\nAST: 11 U/L\nALT: 10 U/L\n\nUrine:\nColor: Amber, cloudy\nRed blood cells: Positive\nProtein: Positive\n\nWhich of the following is the best next step in management?", "answer": "Type IV collagen antibody levels", "options": {"A": "Steroids", "B": "Azithromycin", "C": "Type IV collagen antibody levels", "D": "p-ANCA levels", "E": "Renal biopsy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A previously healthy 5-year-old boy is brought to the emergency department because of fever, irritability, malaise, and left knee pain for 4 days. Four days ago, he fell off his bike and scraped his elbow. His temperature is 39.1°C (102.4°F). The patient walks with a limp. Examination shows swelling and point tenderness over the medial aspect of the left knee. An MRI of the left knee shows edema of the bone marrow and destruction of the medial metaphysis of the tibia. Which of the following is the most likely causal organism?", "answer": "Staphylococcus aureus", "options": {"A": "Staphylococcus epidermidis", "B": "Brucella melitensis", "C": "Staphylococcus aureus", "D": "Pseudomonas aeruginosa", "E": "Pasteurella multocida"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 64-year-old woman presents to her primary care physician complaining of difficulty maintaining her balance while walking. Her husband comes along to the appointment with her, because he feels that she has not been acting herself at home lately. After further questioning him, it is noted that she has recently been voiding urine unintentionally at inappropriate times. If there is suspicion for an intracranial process, what would most likely be seen on MRI and what is the treatment?", "answer": "Dilated ventricles; ventricular shunt", "options": {"A": "Constricted ventricles; ventricular shunt", "B": "Constricted ventricles; surgical resection", "C": "Dilated ventricles; ventricular shunt", "D": "Dilated ventricles; surgical resection", "E": "Constricted ventricles; watch and wait"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man with type 2 diabetes mellitus comes to the physician for a routine health maintenance. He feels well. His blood pressure is 155/60 mm Hg. Physical exam shows no abnormalities. Laboratory studies show a glucose concentration of 150 mg/dL and a hemoglobin A1c concentration of 9%. Treatment with lisinopril is initiated. Which of the following findings would be expected two days after initiating lisinopril therapy?\n $$$ Glomerular filtration rate %%% Renal plasma flow %%% Filtration fraction $$$", "answer": "↓ ↑ ↓", "options": {"A": "↑ no change ↑", "B": "↓ no change ↓", "C": "↓ ↓ no change", "D": "↓ ↑ ↓", "E": "↓ ↓ ↑"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3629-g (8-lb) newborn is examined shortly after spontaneous vaginal delivery. She was delivered at 40 weeks' gestation and pregnancy was uncomplicated. Her mother is concerned because she is not moving her left arm as much as her right arm. Physical examination shows her left arm to be adducted and internally rotated, with the forearm extended and pronated, and the wrist flexed. The Moro reflex is present on the right side but absent on the left side. Which of the following brachial plexus structures is most likely injured in this infant?", "answer": "Upper trunk", "options": {"A": "Upper trunk", "B": "Long thoracic nerve", "C": "Lower trunk", "D": "Axillary nerve", "E": "Posterior cord"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman presents to the office complaining of bilateral joint pain and stiffness in her hand joints for the past 3 months. She reports increasing difficulty holding a coffee cup or pen due to stiffness, especially in the morning. Over-the-counter ibuprofen partially relieves her symptoms. Past medical history is significant for dysthymia and gastroesophageal reflux disease. Vital signs are normal except for a low-grade fever. On examination, there is mild swelling and tenderness in the proximal interphalangeal and metacarpophalangeal joints and wrists. Nontender and non-pruritic nodules near the elbows are noted. Chest and abdominal examination are normal. X-rays of the hands reveal soft tissue swelling, joint space narrowing, and bony erosions. Her hematocrit is 32%, and her erythrocyte sedimentation rate is 40 mm/hr. This patient is at greatest risk for which of the following?", "answer": "Osteoporosis", "options": {"A": "Disease progression to distal interphalangeal joints", "B": "Osteoporosis", "C": "Sacroiliac joint inflammation", "D": "Obstructive pulmonary disease", "E": "Osteitis deformans"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old woman comes to the physician for a preoperative examination before undergoing a planned elective cholecystectomy. She has a history of myasthenia gravis, for which she takes oral pyridostigmine. She has had occasional episodes of muscle weakness, blurred vision, and slurred speech recently. Physical examination shows mild ptosis bilaterally. The pupils are normal in size and reactive bilaterally. Muscle strength is 3/5 at the hips and shoulders. Sensory examination shows no abnormalities. After the administration of 10 mg of edrophonium, her ptosis resolves, and her proximal muscle strength improves to 5/5. This patient is most likely to benefit from which of the following interventions?", "answer": "Increase the dose of pyridostigmine", "options": {"A": "Administer timed doses of edrophonium", "B": "Increase the dose of pyridostigmine", "C": "Discontinue treatment with pyridostigmine", "D": "Initiate treatment with intravenous atropine", "E": "Add glycopyrrolate as needed"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old woman presents to the emergency department with abdominal pain. She states that she was eating dinner when she suddenly felt abdominal pain and nausea. The pain did not improve after 30 minutes, so her husband brought her in. The patient has a past medical history of diabetes that is well-treated with exercise and metformin. Her temperature is 101°F (38.3°C), blood pressure is 147/98 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam reveals right upper quadrant tenderness and guaiac negative stools. Which of the following is optimal management for this patient's condition?", "answer": "NPO, IV fluids, analgesics, antibiotics, cholescystecomy within 72 hours", "options": {"A": "NPO, IV fluids, analgesics, antibiotics", "B": "NPO, IV fluids, analgesics, antibiotics, emergent cholecystectomy", "C": "NPO, IV fluids, analgesics, antibiotics, cholescystecomy within 24 hours", "D": "NPO, IV fluids, analgesics, antibiotics, cholescystecomy within 48 hours", "E": "NPO, IV fluids, analgesics, antibiotics, cholescystecomy within 72 hours"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An otherwise healthy 56-year-old man comes to the physician for a 2-year history of recurrent upper abdominal pain and fullness that worsens after meals. Urea breath test is positive. An endoscopy shows diffuse mucosal atrophy and patchy erythema, but no ulcer. A biopsy from which of the following areas is most likely to yield an accurate diagnosis?", "answer": "Gastric antrum", "options": {"A": "Gastric fundus", "B": "Distal esophagus", "C": "Gastric antrum", "D": "Duodenal bulb", "E": "Gastric pylorus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "To study the flow of blood in the systemic circulation, partially occlusive stents are placed in the pulmonary trunk of a physiological system while the pressure in the right atrium is monitored. A graph where the right atrial pressure is a function of venous return is plotted. Assuming all circulatory nerve reflexes are absent in the system, at what point on the diagram shown below will the arterial pressure be closest to the venous pressure?", "answer": "Point III", "options": {"A": "Point I", "B": "Point II", "C": "Point III", "D": "Point IV", "E": "Point V"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 63-year-old man presents to the emergency room with severe upper abdominal pain. His symptoms started 2 days prior to presentation and have progressed rapidly. He has been seen in the emergency room 3 times in the past year for acute alcohol intoxication. His past medical history is notable for multiple deep venous thromboses, hypertension, diabetes mellitus, gout, and a transient ischemic attack one year prior. He takes warfarin, lisinopril, metformin, glyburide, and allopurinol. His temperature is 100.0°F (37.8°C), blood pressure is 100/55 mmHg, pulse is 130/min, and respirations are 26/min. On exam, he is in acute distress but is able to answer questions appropriately. Hepatomegaly, splenomegaly, and scleral icterus are noted. There is a positive fluid wave. Laboratory analysis reveals an INR of 1.3. An abdominal ultrasound is ordered, and the patient is started on the appropriate management. However, before the ultrasound can begin, he rapidly loses consciousness and becomes unresponsive. He expires despite appropriate management. An autopsy the following day determines the cause of death to be a massive cerebrovascular accident. A liver biopsy demonstrates darkly erythematous congested areas in the centrilobular regions. This patient’s presenting symptoms are most likely caused by obstructive blood flow in which of the following vessels?", "answer": "Hepatic vein", "options": {"A": "Common hepatic artery", "B": "Hepatic vein", "C": "Inferior vena cava", "D": "Portal vein", "E": "Splenic vein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old African American male presents to his family physician for “spots” on his foot. Yesterday, he noticed brown spots on his foot that have a whitish rim around them. The skin lesions are not painful, but he got particularly concerned when he found similar lesions on his penis that appear wet. He recalls having pain with urination for the last 4 weeks, but he did not seek medical attention until now. He also has joint pain in his right knee which started this week. He is sexually active with a new partner and uses condoms inconsistently. His physician prescribes a topical glucocorticoid to treat his lesions. Which of the following risk factors is most commonly implicated in the development of this condition?", "answer": "HLA B27 allele", "options": {"A": "Race", "B": "HLA B27 allele", "C": "Co-infection with HIV", "D": "Diagnosis with psoriasis", "E": "Increased CRP serum levels"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old pregnant female presents for a prenatal check-up at 20 weeks gestation, which includes routine screening ultrasound. Fetal ultrasound demonstrates bilateral multicystic dysplastic kidneys. Her pregnancy has been complicated by persistent oligohydramnios. The child requires significant pulmonary support upon delivery. Which of the following clinical findings is most likely present in this child as a result of these abnormalities?", "answer": "Clubbed feet", "options": {"A": "Urachal fistula", "B": "Esophageal atresia", "C": "Spina bifida occulta", "D": "Clubbed feet", "E": "Macrosomia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to the hospital for evaluation, he is accompanied by agents from child protective services after he was rescued from a home where he was being neglected. He was found locked in a closet and says that he was fed only once every 2 days for the past month. On presentation, he is found to be extremely emaciated with protruding ribs and prominent joints. He is provided with an appropriate rehydration and nourishment therapy. Despite his prolonged nutritional deprivation, the patient demonstrates appropriate cognitive function for his age. The transporter responsible for preventing cognitive decline in this malnourished patient has which of the following characteristics?", "answer": "Has high affinity for glucose", "options": {"A": "Facilitates insulin release", "B": "Has high affinity for glucose", "C": "Responsive to insulin", "D": "Has high affinity for fructose", "E": "Transports glucose against its concentration gradient"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman comes to the physician because of vaginal discharge for 4 days. Her last menstrual period was 3 weeks ago. Twelve months ago, she was diagnosed with trichomoniasis, for which she and her partner were treated with a course of an antimicrobial. She is sexually active with one male partner, and they use condoms inconsistently. Her only medication is a combined oral contraceptive that she has been taking for the past 4 years. A Gram stain of her vaginal fluid is shown. Which of the following is the most likely causal organism?", "answer": "Neisseria gonorrhoeae", "options": {"A": "Neisseria gonorrhoeae", "B": "Gardnerella vaginalis", "C": "Haemophilus ducreyi", "D": "Klebsiella granulomatis", "E": "Treponema pallidum"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old woman presents to the physician for a routine physical examination. She has type 2 diabetes that she treats with metformin. Her pulse is 85/min, respiratory rate is 15/min, blood pressure is 162/96 mm Hg, and temperature is 37.0°C (98.6°F). Treatment with a first-line drug is initiated. Which of the following is the most likely effect of this medication?\n  24-hour urine sodium Aldosterone Angiotensin II Peripheral vascular resistance Renin\nA Increased Decreased Decreased Decreased Increased\nB Increased Decreased Decreased Decreased Decreased\nC Increased Increased Increased Increased Increased\nD Decreased Increased Increased Decreased Increased\nE Increased Decreased Increased Decreased Increased", "answer": "A", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old man comes to the physician because of a 6-month history of numbness and burning sensation in his feet that is worse at rest. He has not been seen by a physician in several years. He is 178 cm (5 ft 10 in) tall and weighs 118 kg (260 lb); BMI is 37.3 kg/m2. Physical examination shows decreased sensation to pinprick, light touch, and vibration over the soles of both feet. Ankle jerk is 1+ bilaterally. His hemoglobin A1C concentration is 10.2%. Which of the following pathophysiological processes is most likely to be involved in this patient's condition?", "answer": "Accumulation of islet amyloid polypeptide", "options": {"A": "Accumulation of islet amyloid polypeptide", "B": "Complement-mediated destruction of insulin receptors", "C": "Increased production of adiponectin by adipocytes", "D": "Expression of human leukocyte antigen subtype DR4", "E": "Lymphocytic infiltration of islet cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old woman who works as a chef is brought to the hospital for evaluation of burns sustained in a kitchen accident. Physical examination reveals 3rd-degree burns over the anterior surface of the right thigh and the lower limbs, which involve approx. 11% of the total body surface area (TBSA). The skin in the burned areas is thick and painless to touch, and the dorsalis pedis pulses are palpable but weak. Which of the following is the most appropriate next step in management?", "answer": "Early excision and split-thickness skin grafting", "options": {"A": "Early excision and full-thickness skin grafting", "B": "Early excision and split-thickness skin grafting", "C": "Delayed excision and skin grafting", "D": "Topical antibiotic application of mafenide acetate", "E": "Fluid resuscitation with Ringer’s lactate solution per the Parkland formula"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 7-year-old boy with a past medical history significant only for prior head lice infection presents to the clinic after being sent by the school nurse for a repeat lice infection. The boy endorses an itchy scalp, but a review of systems is otherwise negative. After confirming the child’s diagnosis and sending him home with appropriate treatment, the school nurse contacts the clinic asking for recommendations on how to prevent future infection. Which of the following would be the best option to decrease the likelihood of lice reinfestation?", "answer": "Treatment of household members with topical ivermectin", "options": {"A": "Observation with close monitoring", "B": "Encourage family to move out of their home", "C": "Treatment of household members with topical ivermectin", "D": "Treatment with oral albendazole", "E": "Treatment with topical clindamycin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old woman at 6 weeks gestation seeks evaluation at a local walk-in clinic because she has noticed a clear, sticky discharge from her right nipple for the past 1 week. The discharge leaves a pink stain on her bra. She does not have pain in her breasts and denies changes in skin color or nipple shape. The past medical history is significant for a major depressive disorder, for which she takes fluoxetine. The family history is negative for breast, endometrial, and ovarian cancers. The physical examination is unremarkable. There are no palpable masses or tenderness on breast exam and no skin discoloration or ulcers. The breasts are symmetric. The nipple discharge on the right side is a pink secretion that is sticky. There are no secretions on the left. The axillary lymph nodes are normal. Which of the following is the most likely diagnosis?", "answer": "Papilloma", "options": {"A": "Mastitis", "B": "Drug-induced", "C": "Papilloma", "D": "Breast cancer", "E": "Lactation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old woman, gravida 3, para 3, comes to the physician because her left breast has become larger, hot, and itchy over the past 2 months. The patient felt a small lump in her left breast 1 year ago but did not seek medical attention at that time. She has hypertension and hyperlipidemia. Menarche was at the age of 11 years and menopause at the age of 46 years. Her mother died of breast cancer at the age of 45 years. The patient does not smoke or drink alcohol. Current medications include labetalol, simvastatin, and daily low-dose aspirin. She is 170 cm (5 ft 7 in) tall and weighs 78 kg (172 lb); BMI is 27 kg/m2. Her temperature is 37.7°C (99.9°F), pulse is 78/min, and blood pressure is 138/88 mm Hg. Examination shows large dense breasts. There is widespread erythema and edematous skin plaques over a breast mass in the left breast. The left breast is tender to touch and left-sided axillary lymphadenopathy is noted. Which of the following is the most likely diagnosis?", "answer": "Inflammatory breast cancer", "options": {"A": "Paget's disease of the breast", "B": "Mastitis", "C": "Breast fibroadenoma", "D": "Breast abscess", "E": "Inflammatory breast cancer"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old man is brought to the emergency department 25 minutes after an episode of violent jerky movements of his arms and legs. He has no recollection of the episode. The episode lasted for 3–4 minutes. His girlfriend reports that he has not been sleeping well over the past month. He is only oriented to place and person. His temperature is 37°C (98.6°F), pulse is 99/min, respirations are 18/min, and blood pressure is 110/80 mm Hg. Neurologic examination shows no focal findings. A complete blood count as well as serum concentrations of glucose, electrolytes, and calcium are within the reference range. Urine toxicology screening is negative. An MRI of the brain shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Electroencephalography", "options": {"A": "Lorazepam", "B": "Lumbar puncture", "C": "Tilt table test", "D": "Electroencephalography", "E": "Lamotrigine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 60-year-old man is admitted to the ER for a severe persistent abdominal pain of 6 hours duration with nausea, vomiting, and steatorrhea. His medical history is relevant for multiple similar episodes of abdominal pain, hypertension, a recent fasting plasma glucose test of 150 mg/dL, and an HbA1c of 7.8%. His temperature is 37°C (98.6°F), respirations are 15/min, pulse is 67/min, and blood pressure is 122/98 mm Hg. Physical examination is positive for epigastric tenderness. A computed tomography of the abdomen of the patient is shown in the picture. Which of the following laboratory results is most specific for this patient's condition?", "answer": "Low serum trypsin, low stool elastase", "options": {"A": "Elevated amylase, elevated lipase", "B": "Low serum trypsin, low stool elastase", "C": "Elevated ALT, elevated gamma-glutamyl transpeptidase", "D": "High serum trypsin, high stool elastase", "E": "Elevated alkaline phosphatase, elevated total bilirubin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying the effect of chromatin structure on gene regulation. The investigator isolates a class of proteins that compact DNA by serving as spools upon which DNA winds around. These proteins are most likely rich in which of the following compounds?", "answer": "Lysine and arginine", "options": {"A": "Phosphate", "B": "Proline and alanine", "C": "Heparan sulfate", "D": "Lysine and arginine", "E": "Disulfide-bonded cysteine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 73-year-old man comes to the physician because of a 2-month history of intermittent blood in his stool. He has had no pain with defecation. Physical examination shows a 2-cm mass located above the dentate line. Further evaluation of the mass confirms adenocarcinoma. Which of the following describes the most likely route of hematogenous spread of the malignancy?", "answer": "Superior rectal vein → inferior mesenteric vein → hepatic portal vein", "options": {"A": "Superior rectal vein → inferior mesenteric vein → hepatic portal vein", "B": "Inferior rectal vein → inferior mesenteric vein → splenic vein", "C": "Inferior rectal vein → internal pudendal vein → internal iliac vein", "D": "Superior rectal vein → superior mesenteric vein → hepatic portal vein", "E": "Inferior rectal vein → internal pudendal vein → external iliac vein"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 12-year-old boy and his mother are brought to the emergency department after a motor vehicle accident. The boy was an unrestrained passenger in a head-on collision and was ejected from the front seat. The patient's mother was the driver and she is currently being resuscitated. Neither the child nor the mother are conscious; however, it is documented that the family are all Jehovah's witnesses and would not want a transfusion in an acute situation. The husband/father arrives to the trauma bay and confirms this wish that everyone in the family would not want a transfusion in accordance with their beliefs. The father is confirmed as the official healthcare proxy. Which of the following is the best next step in management?", "answer": "Do not transfuse the mother and transfuse the boy", "options": {"A": "Consult the hospital ethics committee", "B": "Do not transfuse the boy and transfuse the mother", "C": "Do not transfuse the boy or the mother", "D": "Do not transfuse the mother and transfuse the boy", "E": "Transfuse the boy and mother"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 68-year-old woman comes to the physician because of increasing heartburn for the last few months. During this period, she has taken ranitidine several times a day without relief and has lost 10 kg (22 lbs). She has retrosternal pressure and burning with every meal. She has had heartburn for several years and took ranitidine as needed. She has hypertension. She has smoked one pack of cigarettes daily for the last 40 years and drinks one glass of wine occasionally. Other current medications include amlodipine and hydrochlorothiazide. She appears pale. Her height is 163 cm (5 ft 4 in), her weight is 75 kg (165 lbs), BMI is 27.5 kg/m2. Her temperature is 37.2°C (98.96°F), pulse is 78/min, and blood pressure is 135/80 mm Hg. Cardiovascular examination shows no abnormalities. Abdominal examination shows mild tenderness to palpation in the epigastric region. Bowel sounds are normal. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 10.2 g/dL\nMean corpuscular volume 78 μm\nMean corpuscular hemoglobin 23 pg/cell\nLeukocyte count 9,500/mm3\nPlatelet count 330,000/mm3\nSerum\nNa+ 137 mEq/L\nK+ 3.8 mEq/L\nCl- 100 mEq/L\nHCO3- 25 mEq/L\nCreatinine 1.2 mg/dL\nLactate dehydrogenase 260 U/L\nAlanine aminotransferase 18 U/L\nAspartate aminotransferase 15 U/L\nLipase (N < 280 U/L) 40 U/L\nTroponin I (N < 0.1 ng/mL) 0.029 ng/mL\nAn ECG shows normal sinus rhythm without ST-T changes. Which of the following is the most appropriate next step in the management of this patient?\"", "answer": "Esophagogastroduodenoscopy", "options": {"A": "24-hour esophageal pH monitoring", "B": "Trial of proton-pump inhibitor", "C": "Esophageal manometry", "D": "Barium swallow", "E": "Esophagogastroduodenoscopy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old man is brought to the emergency department 20 minutes after being involved in a high-speed motor vehicle collision in which he was the unrestrained passenger. His wife confirms that he has hypertension, atrial fibrillation, and chronic lower back pain. Current medications include metoprolol, warfarin, hydrochlorothiazide, and oxycodone. On arrival, he is lethargic and confused. His pulse is 112/min, respirations are 10/min, and blood pressure is 172/78 mm Hg. The eyes open spontaneously. The pupils are equal and sluggish. He moves his extremities in response to commands. There is a 3-cm scalp laceration. There are multiple bruises over the right upper extremity. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. Neurologic examination shows no focal findings. Two large-bore peripheral intravenous catheters are inserted. A 0.9% saline infusion is begun. A focused assessment with sonography in trauma is negative. Plain CT of the brain shows a 5-mm right subdural hematoma with no mass effect. Fresh frozen plasma is administered. Which of the following is most likely to reduce this patient's cerebral blood flow?", "answer": "Hyperventilation", "options": {"A": "Hyperventilation", "B": "Decompressive craniectomy", "C": "Lumbar puncture", "D": "Intravenous hypertonic saline", "E": "Intravenous mannitol"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 29-year-old woman comes to her primary care physician hoping she is pregnant. She reports that she had been taking oral contraceptive pills, but she stopped when she began trying to get pregnant about 7 months ago. Since then she has not had her period. She took a few home pregnancy tests that were negative, but she feels they could be wrong. She says she has gained 4 lbs in the past month, and her breasts feel full. Today, she expressed milk from her nipples. She complains of fatigue, which she attributes to stress at work, and headaches, to which she says “my sister told me she had headaches when she was pregnant.” She denies spotting or vaginal discharge. Her last menstrual period was at age 22, prior to starting oral contraceptive pills. Her medical and surgical history are non-significant. She has no history of sexually transmitted infections. She reports she and her husband are having intercourse 3-4 times a week. Her family history is significant for breast cancer in her mother and an aunt who died of ovarian cancer at 55. On physical examination, no breast masses are appreciated, but compression of the nipples produces whitish discharge bilaterally. A bimanual pelvic examination is normal. A urine pregnancy test is negative. Which of the following is the best initial step in management for this patient?", "answer": "Serum thyroid-stimulating hormone level", "options": {"A": "Mammogram", "B": "Magnetic resonance imaging of the head", "C": "Pelvic ultrasound", "D": "Serum follicle-stimulating hormone/luteinizing hormone ratio", "E": "Serum thyroid-stimulating hormone level"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 72-year-old man comes to the physician for a routine physical examination. He does not take any medications. Physical examination shows no abnormalities. Laboratory studies show a calcium concentration of 8.5 mg/dL, a phosphorus concentration of 3.1 mg/dL, an elevated bone-specific alkaline phosphatase concentration, and a normal urine deoxypyridinoline concentration. Which of the following is the most likely explanation for this patient's laboratory abnormalities?", "answer": "Increased osteoblast activity", "options": {"A": "Increased parafollicular C-cell activity", "B": "Decreased osteoclast activity", "C": "Increased osteoblast activity", "D": "Decreased parathyroid chief cell activity", "E": "Increased chondroblast activity"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman who has never been pregnant presents to the physician for a follow-up examination. She has had 5 months of deep pain during sexual intercourse and pelvic pain that intensified prior to her menses. The pain has not subsided despite taking oral contraceptives. She denies any vaginal discharge or foul smell. She is in a monogamous relationship with her husband of 2 years. She has no history of any serious illnesses. Her vital signs are within normal limits. Physical examination shows tenderness on deep palpation of the hypogastrium. A speculum examination of the vagina and cervix shows no abnormalities or discharge. Serum studies show a beta hCG of 6 mIU/mL. A transabdominal ultrasound shows no abnormalities. Which of the following is most likely to establish a diagnosis?", "answer": "Laparoscopy", "options": {"A": "Abdominopelvic computed tomography (CT) scan", "B": "Cancer antigen 125 (CA-125)", "C": "Laparoscopy", "D": "Dilation and curettage", "E": "Wet-mount test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 62-year-old woman with metastatic breast cancer comes to the physician because of a 2-day history of fever, chills, and new gluteal lesions. The lesions began as painless red macules and evolved into painful ulcers overnight. She received her fourth course of palliative chemotherapy 2 weeks ago. Her temperature is 38.2°C (100.8°F). Laboratory studies show a leukocyte count of 2,000/mm3 (20% segmented neutrophils). A photograph of one of the skin lesions is shown. Which of the following virulence factors is most likely involved in the pathogenesis of this patient's skin finding?", "answer": "Exotoxin A", "options": {"A": "Edema toxin", "B": "Heat-stable toxin", "C": "Toxic shock syndrome toxin-1", "D": "Exotoxin A", "E": "Endotoxin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 61-year-old female presents to her primary care physician complaining of fatigue and feeling sad. She reports that ever since her husband passed away 3 months ago, she has noticed a decrease in her energy level and reports frequently awaking at 2 in the morning and cannot fall back asleep. She sometimes wakes up and hears her husband's voice, constantly thinks about how much she misses him, and has recently thought about ways to kill herself including driving through a red light. She used to be an active member of her neighborhood’s bridge club but has stopped playing. She has lost 15 pounds and rarely feels hungry. Which of the following is the most likely diagnosis in this patient?", "answer": "Major depressive disorder", "options": {"A": "Bipolar II disorder", "B": "Major depressive disorder", "C": "Acute grief", "D": "Persistent depressive disorder", "E": "Schizoaffective disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A physician is describing a case to his residents where a kidney transplant was rapidly rejected by the recipient minutes after graft perfusion. The physician most likely describes all of the following manifestations EXCEPT?", "answer": "Histological evidence of arteriosclerosis", "options": {"A": "Graft mottling", "B": "Graft cyanosis", "C": "Low urine output with evidence of blood", "D": "Histological evidence of arteriosclerosis", "E": "Histological evidence of vascular damage"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man comes to the physician because of a 3-month history of intermittent flank pain and reddish discoloration of urine. His blood pressure is 150/92 mm Hg. His serum creatinine concentration is 1.4 mg/dL. An abdominal CT scan is shown. This patient's condition is most likely caused by a genetic defect in which of the following locations?", "answer": "Short arm of chromosome 16", "options": {"A": "Short arm of chromosome 16", "B": "Short arm of chromosome 3", "C": "Long arm of chromosome 4", "D": "Long arm of chromosome 10", "E": "Short arm of chromosome 6"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought to the physician because of inability to concentrate and difficulties completing assignments at school. His mother says that he frequently interrupts others during conversations at home and that his teachers often reprimand him for talking excessively in school. He refuses to play with the other children and often has physical altercations with his classmates. He can jump up and down but he cannot hop on one foot. He eats without assistance but has difficulty using silverware. He cannot follow three-step directions. There is no family history of serious illness. Examination shows a small head, wide-spaced eyes, and short palpebral fissures. His upper lip is thin and flat. He has a sunken nasal bridge and a small jaw. There is a 3/6 pansystolic murmur heard along the left lower sternal border. Which of the following is the most likely cause of these findings?", "answer": "Prenatal alcohol exposure", "options": {"A": "Nondisjunction of chromosome 21", "B": "Deletion of long arm of chromosome 7", "C": "Prenatal alcohol exposure", "D": "FMR1 gene mutation", "E": "Maternal intake of phenytoin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old female is brought in by ambulance with altered mental status. She is in a comatose state, but is breathing spontaneously with deep and rapid respirations. Her vital signs are as follows: T 100.2F, BP 92/54 mmHg, HR 103 bpm, RR 28, and SpO2 97% on room air. Complete blood count reveals: WBC 12.7, hemoglobin 11.3, platelets 254. Basic metabolic panel reveals: sodium 137, potassium 4.2, chloride 100, bicarbonate 16, creatinine 1.78 An ABG is performed which showed pH 7.38, PaO2 94, PaCO2 26. Which of the following is the most likely cause of this patient’s presentation?", "answer": "Medication overdose", "options": {"A": "Undiagnosed type 1 diabetes mellitus", "B": "Severe sepsis", "C": "Medication overdose", "D": "Acute renal failure", "E": "Alcohol binging"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Researchers are studying the relationship between heart disease and alcohol consumption. They review the electronic medical records of 500 patients at a local hospital during the study period and identify the presence or absence of acute coronary syndrome (ACS) and the number of alcoholic drinks consumed on the day of presentation. The researchers determine the prevalence of ACS and of alcoholic drink consumption. They correlate the relationship between these two variables and find that patients who reported no alcohol consumption or 1 drink only that day had a lower risk of acute coronary syndrome than patients who reported 2 or more drinks. Which of the following is the most accurate description of this study type?", "answer": "Cross-sectional study", "options": {"A": "Randomized controlled trial", "B": "Case-control study", "C": "Cross-sectional study", "D": "Retrospective study", "E": "Prospective study"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 69-year-old man is brought to the emergency department because of a 1-week history of recurring black stools. On questioning, he reports fatigue and loss of appetite over the last 3 months. Twenty years ago, he underwent a partial gastrectomy for peptic ulcer disease. The patient's father died of metastatic colon cancer at the age of 57 years. He is 163 cm (5 ft 4 in) tall and weighs 55 kg (121 lb); BMI is 20.8 kg/m2. He appears chronically ill. His temperature is 36.5°C (97.7°F), pulse is 105/min, and blood pressure is 115/70 mm Hg. The conjunctiva appear pale. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. There is a well-healed scar on the upper abdomen. His hemoglobin concentration is 10.5 g/dL and his mean corpuscular volume is 101 μm3. An upper endoscopy shows a large nodular mass on the anterior wall of the lesser curvature of the gastric stump. Biopsy samples are obtained, showing polypoid, glandular formation of irregular-shaped and fused gastric cells with intraluminal mucus, demonstrating an infiltrative growth. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Abdominopelvic CT scan", "options": {"A": "Stool antigen test for H. pylori", "B": "Laparoscopy", "C": "Treatment with PPI, clarithromycin, and amoxicillin", "D": "Abdominopelvic CT scan", "E": "Vitamin B12 assessment"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 21-year-old woman comes to the physician because of a 4-month history of fatigue. She admits to binge eating several times per month, after which she usually induces vomiting for compensation. She exercises daily in an effort to lose weight. She is 168 cm (5 ft 6 in) tall and weighs 60 kg (132 lb); BMI is 21.3 kg/m2. Physical examination shows calluses on the knuckles and bilateral parotid gland enlargement. Oropharyngeal examination shows eroded dental enamel and decalcified teeth. Which of the following is the most appropriate pharmacotherapy for this patient's condition?", "answer": "Fluoxetine", "options": {"A": "Orlistat", "B": "Mirtazapine", "C": "Buspirone", "D": "Venlafaxine", "E": "Fluoxetine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old man comes to the physician with his wife for evaluation of infertility. They have been unable to conceive for 2 years. The man reports normal libido and erectile function. He has smoked one pack of cigarettes daily for 13 years. He does not take any medications. He has a history of right-sided cryptorchidism that was surgically corrected when he was 7 years of age. Physical examination shows no abnormalities. Analysis of his semen shows a low sperm count. Laboratory studies are most likely to show which of the following?", "answer": "Decreased inhibin B concentration", "options": {"A": "Increased placental ALP concentration", "B": "Increased prolactin concentration", "C": "Decreased inhibin B concentration", "D": "Decreased FSH concentration", "E": "Decreased testosterone concentration"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old boy was brought to the emergency department because of palpitations and lightheadedness that began 16 hours ago. He admitted to binge drinking the night before. He was sedated and electrically cardioverted. An ECG that was recorded following cardioversion is shown. After regaining consciousness, he was admitted for observation. Serum concentration of creatinine and electrolytes were measured to be within the reference range. Twelve hours after cardioversion, the patient complains again of palpitations. He does not have lightheadedness or chest pain. His temperature is 37.1°C (98.8°F), pulse is 220/min, respirations are 20/min, and blood pressure is 112/84 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Physical examination shows no abnormalities. A newly recorded ECG shows a shortened PR interval, and wide, monomorphic QRS complexes with a regular rhythm. Which of the following is the most appropriate next best step in management?", "answer": "Administer procainamide", "options": {"A": "Administer magnesium sulfate", "B": "Administer verapamil", "C": "Administer atenolol", "D": "Administer procainamide", "E": "Administer adenosine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old girl is brought to the emergency department after falling about from a chair and injuring her right leg. During the past 2 years, she has had two long bone fractures. She is at the 5th percentile for height and 20th percentile for weight. Her right lower leg is diffusely erythematous. The patient withdraws and yells when her lower leg is touched. A photograph of her face is shown. An x-ray of the right lower leg shows a transverse mid-tibial fracture with diffusely decreased bone density. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Type 1 collagen defect", "options": {"A": "Type 3 collagen defect", "B": "Type 5 collagen defect", "C": "Type 1 collagen defect", "D": "Type 4 collagen defect", "E": "Type 2 collagen defect"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old woman with type 1 diabetes mellitus suddenly develops tremors, cold sweats, and confusion while on a backpacking trip with friends. She is only oriented to person and is unable to follow commands. Her fingerstick blood glucose concentration is 28 mg/dL. Her friend administers an intramuscular injection with a substance that reverses her symptoms. Which of the following is the most likely mechanism of action of this drug?", "answer": "Activation of adenylyl cyclase", "options": {"A": "Activation of glucokinase", "B": "Inhibition of glucose-6-phosphatase", "C": "Inhibition of α-glucosidase", "D": "Activation of adenylyl cyclase", "E": "Inhibition of glycogen phosphorylase\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old diabetic man presents with fever, headache, and excruciating pain in his right eye for the past 2 days. He says that he has been taking sitagliptin and metformin regularly. He endorses recently having a sore throat. On examination, vesicles are present in groups with an erythematous base on the upper eyelid, forehead, and nose on the right half of his face. The patient is prescribed an antiviral agent and sent home. Which of the following nerves is most likely involved?", "answer": "Ophthalmic nerve", "options": {"A": "Nasociliary nerve", "B": "Ophthalmic nerve", "C": "Supraorbital nerve", "D": "Supratrochlear nerve", "E": "Lacrimal nerve"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old man presents to his primary care provider with recent swelling in his legs that has now spread to the lower part of his thighs. He sometimes has difficulty putting on his shoes and pants. He also noticed puffiness under his eyes over the last 3 weeks. A 24-hour urine collection confirms proteinuria of 5 g/day. Electron microscopy of a renal biopsy specimen reveals subepithelial deposits with a spike and dome pattern. Which of the following is associated with this patient’s condition?", "answer": "Hepatitis B infection", "options": {"A": "HIV infection", "B": "High HbA1C", "C": "Hepatitis B infection", "D": "Hodgkin's lymphoma", "E": "Monoclonal protein spike"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old woman comes to the physician for an annual routine examination. Menses occur at regular 28-day intervals and last for 4 days with normal flow. Her last menstrual period was 3 weeks ago. She is sexually active with one male partner and they use condoms consistently. The patient is 160 cm (5 ft 3 in) tall and weighs 72 kg (150 lb); BMI is 28.1 kg/m2. She feels well. Pelvic examination shows a smooth, mobile right adnexal mass. A subsequent ultrasound of the pelvis shows a single, 2-cm large, round, hypoechoic mass with a thin, smooth wall in the right ovary. The mass has posterior wall enhancement, and there are no signs of blood flow or septae within the mass. Which of the following is the most appropriate next step in management?", "answer": "Follow-up examination", "options": {"A": "Diagnostic laparoscopy", "B": "CA-125 level", "C": "CT scan of the pelvis", "D": "Oral contraceptive", "E": "Follow-up examination"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 21-year-old man presents with fever, headache, and clouded sensorium for the past 3 days. His fever is low-grade. He says his headache is mild-to-moderate in intensity and associated with nausea, vomiting, and photophobia. There is no history of a sore throat, pain on urination, abdominal pain, or loose motions. He smokes 1–2 cigarettes daily and drinks alcohol socially. Past medical history and family history are unremarkable. His vital signs include: blood pressure 120/80 mm Hg, pulse 106/min, temperature 37.3°C (99.2°F). On physical examination, he is confused, disoriented, and agitated. Extraocular movements are intact. The neck is supple on flexion. He is moving all his 4 limbs spontaneously. A noncontrast CT scan of the head is within normal limits. A lumbar puncture is performed, and cerebrospinal fluid results are still pending. The patient is started on empiric intravenous acyclovir. Which of the following clinical features favors encephalitis rather than meningitis?", "answer": "Clouded sensorium", "options": {"A": "Clouded sensorium", "B": "Fever", "C": "Headache", "D": "Nausea and vomiting", "E": "Photophobia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 68-year-old man comes to the physician because of a 3-month history of anorexia, weight loss, and cough productive of blood-tinged sputum with yellow granules. Four months ago he was treated for gingivitis. He has smoked 1 pack of cigarettes daily for 40 years. Examination shows crackles over the right upper lung field. An x-ray of the chest shows a solitary nodule and one cavitary lesion in the right upper lung field. A photomicrograph of a biopsy specimen from the nodule obtained via CT-guided biopsy is shown. Which of the following is the most appropriate pharmacotherapy?", "answer": "Penicillin G", "options": {"A": "Penicillin G", "B": "Cisplatin and paclitaxel", "C": "Trimethoprim-sulfamethoxazole", "D": "Rifampin, isoniazid, pyrazinamide, and ethambutol", "E": "Itraconazole"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 70-year-old man comes to the physician because of intermittent shortness of breath while going up stairs and walking his dog. It began about 1 month ago and seems to be getting worse. He has also developed a dry cough. He has not had any wheezing, fevers, chills, recent weight loss, or shortness of breath at rest. He has a history of Hodgkin lymphoma, for which he was treated with chemotherapy and radiation to the chest 7 years ago. He also has hypertension, for which he takes lisinopril. Ten years ago, he retired from work in the shipbuilding industry. He has smoked half a pack of cigarettes daily since the age of 21. Vital signs are within normal limits. On lung auscultation, there are mild bibasilar crackles. A plain x-ray of the chest shows bilateral ground-glass opacities at the lung bases and bilateral calcified pleural plaques. Which of the following is the greatest risk factor for this patient's current condition?", "answer": "Occupational exposure", "options": {"A": "Occupational exposure", "B": "Smoking", "C": "Advanced age", "D": "Family history", "E": "Radiation therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old obese woman presents with changes in her left breast. The patient states that, about a month ago, she noticed that she was able to feel a hard mass in the upper outer quadrant of her left breast, which has not gone away. In addition, her nipple and skin overlying the breast have started to look different. Past medical history is significant for the polycystic ovarian syndrome (PCOS) and hypertension, well-managed with lisinopril. The patient has never been pregnant. Menopause was at age 53. Family history is significant for breast cancer in her mother at age 55, and her father who died of lung cancer at age 52. A review of systems is significant for a 13.6 kg (30 lb) weight loss in the last 2 months despite no change in diet or activity. Vitals include: temperature 37.0°C (98.6°F), blood pressure 120/75 mm Hg, pulse 97/min, respiratory rate 16/min, and oxygen saturation 99% on room air. The physical exam is significant for a palpable, hard, fixed mass in the upper outer quadrant of the left breast, as well as nipple retraction and axillary lymphadenopathy. Mammography of the left breast reveals a spiculated mass in the upper outer quadrant. A biopsy confirms invasive ductal carcinoma. Molecular analysis reveals that the tumor cells are positive for a receptor that is associated with a poor prognosis. Which of the following are indicated as part of this patient’s treatment?", "answer": "Trastuzumab", "options": {"A": "Goserelin", "B": "Tamoxifen", "C": "Trastuzumab", "D": "Anastrozole", "E": "Raloxifene"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 11-year-old boy is brought to the doctor by his father because his father is worried about the boy's performance in school and his lack of a social life. His father is also worried about the ongoing bullying his son is experiencing due to swearing outbursts the boy has exhibited for several years. During these outbursts, the boy contorts his face, blinks repeatedly, and grunts. His father is worried that the bullying will worsen and would like to see if there is a medication that can help his son. Which of the following medications is most likely to be beneficial?", "answer": "Risperidone", "options": {"A": "Valproic acid", "B": "Risperidone", "C": "Lamotrigine", "D": "Clonazepam", "E": "Lithium"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 54-year-old woman presents to the emergency room after falling on her right side at a bar and breaking her clavicle and 2 ribs. Her husband reports that she has had a 6-month history of diarrhea and has lost 6.8 kg (15 lb) over the last year without dieting or exercising. She has a family history of type I diabetes. On physical exam, ecchymosis is noted over her entire right shoulder, extending to her sternum and over her broken ribs. She also has other bruises in various stages of healing. Her abdomen is diffusely tender, radiating to her back, and there is a palpable midepigastric mass. The woman has a positive Romberg test, but the rest of her examination is normal. She is admitted for further evaluation. Her labs and pancreas biopsy histology are as follows:\nLaboratory tests\nSerum chemistries \nAlbumin 5.1 g/dL\nAmylase 124 U/L\nLipase 146 U/L\nBlood glucose (fasting)  180 mg/dL\nTriglycerides 140 mg/dL\nCholesterol, total 210 mg/dL\nHDL 25 mg/dL\nLDL 165 mg/dL\nSerum electrolytes \nSodium 137 mEq/L\nPotassium 3.5 mEq/L\nChloride 90 mEq/L\nInternational normalized ratio 2.5\nActivated partial thromboplastin time  30 s\n    Complete blood count\nHemoglobin 12.5 g/dL\nMean corpuscular volume 102 µm3\nPlatelets 150,000/mm3\nLeukocytes 6000/mm3\nStool analysis\nElastase low\nOccult blood absent\nWhich of the following is the best way to manage her condition in the long term?", "answer": "Insulin aspart and glargine with pancreatic enzyme replacement therapy", "options": {"A": "Thiamine and 50% dextrose", "B": "Gemcitabine alone", "C": "Pancreatic resection followed by 5-fluorouracil with leucovorin", "D": "Insulin aspart and glargine", "E": "Insulin aspart and glargine with pancreatic enzyme replacement therapy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old G2P1 female at 37 weeks of gestation presents to the clinic for complaints of right-hand numbness and pain for the past month. She reports that the pain is usually worse at night and that she would sometimes wake up in the middle of the night from the “pins and needles.” She denies fever, weakness, or weight changes but endorses paresthesia and pain. The patient also reports a fall on her right hand 2 weeks ago. A physical examination demonstrates mild sensory deficits at the first 3 digits of the right hand but no tenderness with palpation. Strength is intact throughout. Which of the following findings would further support the diagnosis of this patient’s condition?", "answer": "Tingling when the right wrist is percussed", "options": {"A": "Hairline fracture of the scaphoid bone on magnetic resonance imaging (MRI)", "B": "Loss of sensation at the thenar eminence", "C": "Small cross-sectional area of the median nerve on ultrasonography", "D": "Tingling when the right wrist is percussed", "E": "Tingling when the wrists are extended 90 degrees"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 6-year-old boy presents to his pediatrician’s office for muscle weakness. The patient is accompanied by his mother who states that he has difficulty running and walking up the stairs. The mother has noticed mild weakness when the patient attempts to sit up from a supine position since he was 4-years-old. Medical history is significant for fractures involving the arms and legs secondary to falling. On physical exam, the child does not appear to be in distress and is conversational. He has a waddling gait along with lumbar lordosis and bilateral calf enlargement. The patient uses his hands to push himself into an upright position when arising from the floor. He has absent patellar and ankle-jerk reflexes. Which of the following is the best next step to confirm the diagnosis?", "answer": "Genetic testing", "options": {"A": "Electrocardiogram", "B": "Electromyogram", "C": "Genetic testing", "D": "Muscle biopsy", "E": "Serum creatine kinase level"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old male currently undergoing standard therapy for a recently diagnosed active tuberculosis infection develops sudden onset of fever and oliguria. Laboratory evaluations demonstrate high levels of eosinophils in both the blood and urine. Which of the following is most likely responsible for the patient’s symptoms:", "answer": "Rifampin", "options": {"A": "Rifampin", "B": "Isoniazid", "C": "Pyrazinamide", "D": "Ethambutol", "E": "Return of active tuberculosis symptoms secondary to patient non-compliance with anti-TB regimen"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-year-old boy is brought to the physician for evaluation of a generalized, pruritic rash. The rash began during infancy and did not resolve despite initiating treatment with topical corticosteroids. Three months ago, he was treated for several asymptomatic soft tissue abscesses on his legs. He has been admitted to the hospital three times during the past two years for pneumonia. Physical examination shows a prominent forehead and a wide nasal bridge. Examination of the skin shows a diffuse eczematous rash and white plaques on the face, scalp, and shoulders. Laboratory studies show a leukocyte count of 6,000/mm3 with 25% eosinophils and a serum IgE concentration of 2,300 IU/mL (N = 0–380). Flow cytometry shows a deficiency of T helper 17 cells. The patient’s increased susceptibility to infection is most likely due to which of the following?", "answer": "Impaired chemotaxis of neutrophils", "options": {"A": "Impaired chemotaxis of neutrophils", "B": "Impaired DNA repair in lymphocytes", "C": "Impaired actin assembly in lymphocytes", "D": "Impaired Ig class-switching in lymphocytes", "E": "Impaired interferon-γ secretion by Th1 cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-month-old boy is brought to the pediatrician for a routine check-up. His mother says he is feeding well and has no concerns. He is at the 85th percentile for height and 82nd percentile for weight. Immunizations are up-to-date. Results of serum hepatitis B surface IgG antibody testing are positive. Which of the following best explains this patient's hepatitis B virus status?", "answer": "Passive immunity", "options": {"A": "Window period", "B": "Chronic infection", "C": "Spontaneous recovery", "D": "Vaccination reaction", "E": "Passive immunity"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old man comes to the physician because of progressive pain in his right hip and lower back over the past 4 weeks. He describes the pain as dull and constant. It is worse with exertion and at night. Over the past 2 months, he has helped his son with renovating his home, which required heavy lifting and kneeling. His father died of prostate cancer. He drinks 2–3 beers daily. Vital signs are within normal limits. Examination shows localized tenderness over the right hip and groin area; range of motion is decreased. Hearing is mildly decreased on the right side. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 15 g/dL\nSerum\nTotal protein 6.5 g/dL\nBilirubin 0.8 mg/dL\nAlanine aminotransferase 20 U/L\nAlkaline phosphatase (ALP) 950 U/L\nγ-Glutamyltransferase (GGT) 40 U/L (N=5–50)\nCalcium 9 mg/dL\nPhosphate 4 mg/dL\nParathyroid hormone\n450 pg/mL\nAn x-ray of the hip shows cortical thickening and prominent trabecular markings. Which of the following is the most likely underlying mechanism of this patient's symptoms?\"", "answer": "Increased rate of bone remodeling", "options": {"A": "Proliferation of plasma cells in the bone marrow", "B": "Increased rate of bone remodeling", "C": "Decreased bone mass with microarchitectural disruption", "D": "Infarction of the bone and marrow", "E": "Osteoblastic destruction of the bone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old man comes to the physician because of low-grade fever, dry cough, and shortness of breath. His symptoms began 6 days ago while he was on vacation in Thailand where he went to an urgent care clinic and was started on cefuroxime. His temperature is 38.2°C (100.8°F). Physical examination shows decreased breath sounds at bilateral lung bases. An x-ray of the chest shows diffuse patchy infiltrates. Sputum analysis shows numerous neutrophils but no organisms. Giemsa stain shows epithelial cells with cytoplasmic inclusion bodies. This patient's condition did not improve after the initial treatment because of which of the following properties of the most likely causal pathogen?", "answer": "Lack of peptidoglycan in cell wall", "options": {"A": "Lack of peptidoglycan in cell wall", "B": "Enclosure by polysaccharide capsule", "C": "Formation of biofilms", "D": "Production of β-lactamase enzymes", "E": "Rapid alteration of drug binding sites"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Four days after undergoing a coronary artery bypass graft for coronary artery disease, a 60-year-old man complains of abdominal fullness and bloating. Since his surgery, he has not had a bowel movement and is unable to pass flatus. He has no nausea or vomiting. Prior to the operation, the patient had daily bowel movements without abnormalities. He has a history of bipolar disorder and hypertension. His current medications include aspirin, atorvastatin, chlorpromazine, amlodipine, and prophylactic subcutaneous heparin. His temperature is 39°C (102.2°F), pulse is 110/min, and blood pressure is 120/80 mm Hg. Cardiopulmonary examination shows no abnormalities. Abdominal examination shows a distended, tympanic abdomen with guarding and rebound tenderness; bowel sounds are hypoactive. Abdominal x-ray shows diffuse distention of the colon loops. A CT scan with contrast confirms the x-ray findings and shows a cecal dilation of 14 cm. Which of the following is the most appropriate next step in the management?", "answer": "Laparotomy", "options": {"A": "Nasogastric and rectal tube insertion", "B": "Colonoscopy", "C": "Intravenous neostigmine therapy", "D": "Laparotomy", "E": "Intravenous fluids and bowel rest\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old woman presents with trouble focusing. She says that she has trouble focusing on simple tasks and her thoughts are very scattered. These difficulties have been present since she was a young student in elementary school. She says she had difficulty focusing both at school and at home. The patient is diagnosed with a psychiatric condition and is prescribed the medication that is recommended as the first-line treatment. Which of the following statements is true regarding this new medication?", "answer": "“Appetite suppression is a common side effect of this medication.”", "options": {"A": "“Appetite suppression is a common side effect of this medication.”", "B": "“Bupropion is less effective in adults with this disorder than this medication.”", "C": "“Chronic use of this medication can lead to tardive dyskinesia.”", "D": "“Hypotension is a common side effect of this medication.”", "E": "“Sedation is a common side effect of this medication.”"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 29-year-old woman presents to the fertility clinic due to an inability to conceive. She and her husband have been attempting to have children for over a year. She underwent menarche at 16 years of age and typically has menses every 29 days regularly. Her menstrual periods would last 6 days and are mildly painful. However, she reports that her last menstrual period was 3 months ago. Her medical history is non-contributory and she does not take any medications. Her temperature is 99°F (37.2°C), blood pressure is 125/76 mmHg, pulse is 78/min, and respirations are 15/min. Her body mass index is 26.3 kg/m^2. Physical examination is unremarkable. Urine hCG is negative, serum prolactin level is 75 ng/mL (normal < 20 ng/mL) and thyroid-stimulating hormone is 0.8 microU/mL. Which of the following is the best treatment option for this patient’s infertility?", "answer": "Cabergoline", "options": {"A": "Cabergoline", "B": "Clomiphene", "C": "Levothyroxine", "D": "Letrozole", "E": "Metformin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 47-year-old man with alcoholic cirrhosis comes to the physician for a follow-up examination. Examination of the skin shows erythema over the thenar and hypothenar eminences of both hands. He also has numerous blanching lesions over the trunk and upper extremities that have a central red vessel with thin extensions radiating outwards. Which of the following is the most likely underlying cause of these findings?", "answer": "Increased circulating estrogen", "options": {"A": "Increased circulating ammonia", "B": "Decreased circulating albumin", "C": "Decreased circulating thrombopoietin", "D": "Decreased circulating testosterone", "E": "Increased circulating estrogen"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An otherwise healthy 15-year-old boy comes to the physician for a routine health maintenance examination. He feels well and is doing well in school. He has no history of serious illness. Vital signs are within normal limits. The lungs are clear to auscultation. Cardiac auscultation shows no murmur, but a wide-split S2 that does not change with respiration. If left untreated, this patient is at increased risk for which of the following complications?", "answer": "Paradoxical embolism", "options": {"A": "Sudden cardiac death", "B": "Cerebral aneurysm", "C": "Left ventricular hypertrophy", "D": "Paradoxical embolism", "E": "Infective endocarditis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old woman comes to the physician because of a 4-day history of fever and neck pain that radiates to the jaw and ears. She has also noticed swelling in the front part of her throat since the onset of the pain. She reports feeling anxious and sweating profusely over the past 2 days. She has no history of major illness and takes no medication. Her temperature is 38.1°C (100.6°F), pulse is 95/min, and blood pressure is 140/70 mm Hg. Examination shows moist palms and a bilateral fine resting tremor of the outstretched hands. Examination of the neck shows a thyroid gland that is tender, firm, and enlarged. Serum studies show:\nHemoglobin 12.7 g/dL\nESR 65 mm/h\nSerum\nCreatinine 0.7 mg/dL\nThyroid-stimulating hormone 0.063 μU/mL\nTriiodothyronine (T3) 218 ng/dL\nThyroxine (T4) 88 μg/dL\n123I scan shows an enlarged thyroid gland with multiple areas of decreased uptake. Which of the following is the most likely diagnosis?\"", "answer": "Subacute thyroiditis", "options": {"A": "Subacute thyroiditis", "B": "Thyroid lymphoma", "C": "Struma ovarii", "D": "Factitious hyperthyroidism", "E": "Toxic adenoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 20-year-old female arrives at the urgent care clinic at her university’s health plan asking for an HIV test. She is an undergraduate at the university and just started having sexual intercourse with her new boyfriend. They use protection only occasionally so she wants to get tested to make sure everything is okay. She has never been tested for STDs before. She reports no symptoms and has not seen a physician regularly for any medical conditions in the past. Her family history is uncertain because she was adopted. Her HIV immunoassay and HIV-1/HIV-2 differentiation immunoassay both come back positive. She asks on the phone, “Doctor, tell it to me straight. Do I have AIDS?” Which of the following is the most accurate response?", "answer": "We need additional bloodwork to see if you have AIDS.", "options": {"A": "We have to get a confirmatory PCR test to see if you have AIDS.", "B": "You do not have AIDS because you just started having sex recently.", "C": "You have AIDS but this disease is now a manageable condition.", "D": "We need your partner's information to be sure of your diagnosis.", "E": "We need additional bloodwork to see if you have AIDS."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old woman visits the office with a complaint of recurrent abdominal pain for the past 2 months. She says the pain has been increasing every day and is located in the right upper quadrant. She has been using oral contraceptive pills for the past 2 years. She is a nonsmoker and does not drink alcohol. Her vital signs show a heart rate of 85/min, respiratory rate of 16/min, temperature of 37.6 °C (99.68 °F), and blood pressure of 120/80 mm Hg. Physical examination reveals right upper quadrant tenderness and hepatomegaly 3 cm below the right costal border. Her serology tests for viral hepatitis are as follows:\nHBsAg Negative\nAnti-HBs Negative\nIgM anti-HBc Negative\nAnti-HCV Negative\nA hepatic ultrasound shows hepatomegaly with diffusely increased echogenicity and a well-defined, predominantly hypoechoic mass in segment VI of the right lobe of the liver. What is the most likely diagnosis?", "answer": "Hepatic adenoma", "options": {"A": "Cholangiocarcinoma", "B": "Focal nodular hyperplasia", "C": "Hepatocellular carcinoma", "D": "Metastatic disease", "E": "Hepatic adenoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 67-year-old man comes to the physician because of a history of recurrent right lower abdominal pain for the past 2 years. A CT scan shows a 1.2-cm (0.47-in) mass located in the terminal ileum. He undergoes surgical removal of the mass. A photomicrograph of the resected specimen is shown. Cells from this tissue are most likely to stain positive for which of the following?", "answer": "Chromogranin A", "options": {"A": "Desmin", "B": "Chromogranin A", "C": "Vimentin", "D": "Cytokeratin", "E": "Glial fibrillary acid protein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 66-year-old woman presents to the emergency department with abdominal pain. Her symptoms began when she was eating dinner. She has a past medical history of obesity, constipation, intravenous drug use, and diabetes. The patient is instructed to be nil per os and is transferred to the surgical floor. Three days later she had a cholecystectomy and is recovering on the surgical floor. Her laboratory values are ordered as seen below.\n\nHemoglobin: 11 g/dL\nHematocrit: 33%\nLeukocyte count: 8,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.5 mg/dL\nAlkaline phosphatase: 533 U/L\nGGT: 50 U/L\nAST: 22 U/L\nALT: 20 U/L\n\nThe patient is currently asymptomatic and states that she feels well. Which of the following is associated with this patient's underlying condition?", "answer": "Blastic and lytic skeletal lesions", "options": {"A": "Blastic and lytic skeletal lesions", "B": "Monoclonal plasma cell replication", "C": "Reemergence of a hepatitis infection", "D": "Repeat gastrointestinal tract obstruction", "E": "Qualitative bone defect"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old obese woman is referred to the cardiology clinic for progressive dyspnea. She has had no recent travel or sick contacts. Besides a multivitamin, she has only tried online weight-loss medications for the past five years, including fenfluramine-phentermine. An echocardiogram reveals a dilated right ventricle with systolic pressure of 60 mmHg as well as both tricuspid and pulmonary regurgitation. A right heart catheterization shows a mean pulmonary artery pressure of 40 mmHg. What disease process is most analogous to this patient's presentation?", "answer": "Carcinoid syndrome", "options": {"A": "Subacute endocarditis", "B": "Carcinoid syndrome", "C": "Chronic thromboembolic disease", "D": "Left heart failure", "E": "Chronic obstructive pulmonary disease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 18-year-old man seeks an evaluation from a physician for painful right axillary swelling since 2 days ago. He has malaise. He has no history of serious illnesses and takes no medications. He has a pet kitten which was recently treated for fleas. The temperature is 38.5℃ (101.3℉), the pulse is 88/min, the respiration rate is 14/min, and the blood pressure is 120/80 mm Hg. There are 2 painless papules on the patient’s right forearm that appeared on the healing scratch marks left by his pet kitten a few days ago. Several lymph nodes in the right axilla are enlarged and tender. The overlying skin is erythematous. No other lymphadenopathy is detected in other areas. The rest of the examination shows no abnormalities. Which of the following is the most appropriate pharmacotherapy at this time?", "answer": "No pharmacotherapy", "options": {"A": "Azithromycin", "B": "Doxycycline", "C": "Pyrimethamine", "D": "Streptomycin", "E": "No pharmacotherapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A prospective cohort study was conducted to assess the relationship between LDL-C and the incidence of heart disease. The patients were selected at random. Results showed a 10-year relative risk (RR) of 2.30 for people with elevated LDL-C levels compared to individuals with normal LDL levels. The p value was 0.04. This study is most likely to have which of the following 95% confidence intervals?", "answer": "1.01-3.70", "options": {"A": "1.01-3.70", "B": "1.00-3.60", "C": "0.09-3.50", "D": "0.08-3.40", "E": "0.07-3.30"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old man is brought to the emergency department by police officers because he was seen acting strangely in public. The patient was found talking nonsensically to the characters on cereal boxes in a grocery store. Past medical history is significant for multiple hospitalizations for alcohol-related injuries and alcohol withdrawal seizures. Vital signs are within normal limits. On physical examination, the patient is disheveled and oriented x1. Neurologic examination shows horizontal nystagmus and severe ataxia is also noted, that after interviewing the patient, he forgets the face of persons and the questions asked shortly after he walks out the door. He, however, remembers events from his distant past quite well. Which of the following is the most likely diagnosis in this patient?", "answer": "Korsakoff amnesia", "options": {"A": "Delirium", "B": "Delirium tremens", "C": "Korsakoff amnesia", "D": "Schizophrenia", "E": "Dementia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 76-year-old man presents for a follow-up appointment at his primary care provider’s office. The patient has severe osteoarthritis, which substantially limits his daily physical activity. Several imaging studies have confirmed severe articular degeneration and evidence of bone grinding on bone in his hip joints. The patient suffers from chronic pain and depression that have been resistant to medication. At the physician’s office, his blood pressure is 119/67 mm Hg, the respirations are 18/min, the pulse is 87/min, and the temperature is 36.7°C (98.0°F). On physical examination, the patient has a flat affect and appears anxious. He has significant pain and limited passive and active range of motion of his hip joints bilaterally. This patient would most likely benefit from which of the following procedures if there are no contraindications?", "answer": "Total hip arthroplasty", "options": {"A": "Hip osteotomy", "B": "Hip resurfacing", "C": "Total hip arthroplasty", "D": "Arthroscopic debridement", "E": "Autologous chondrocyte implantation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-year-old boy and the rest of his family visit a physician for a physical after migrating to the United States. His mother reports that her son is always fatigued and has no energy to play like the other kids in their remote village in Nigeria. He was born at 39 weeks via spontaneous vaginal delivery and is meeting all developmental milestones. He is behind on most of his vaccines, and they develop a plan to get him caught up. On examination, the boy presents with jaundice, mild hepatomegaly, and tachycardia. A CBC with manual differential reveals atypical appearing red blood cells. The physician takes time to review the lab work results with the mother, and he discusses her son’s diagnosis. It is expected that one molecule at the biochemical level should be high. Which of the following best describes this molecule and its significance in this patient?", "answer": "Pathological; an intermediate of glycolysis", "options": {"A": "Pathological; an intermediate of glycolysis", "B": "Physiological; an intermediate of gluconeogenesis", "C": "Pathological; an intermediate of the Krebs cycle", "D": "Physiological; an intermediate of the Krebs cycle", "E": "Physiological; found in the mitochondrial intermembrane space"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 14-year-old male of eastern European descent presents to the free clinic at a university hospital for a respiratory infection, which his mother explains occurs quite frequently. The male is noted to be of short stature, have a gargoyle-like facies, clouded corneas, poor dentition, and is severely mentally retarded. A urinalysis revealed large amounts of heparan and dermatan sulfate. Which of the following is the most likely diagnosis?", "answer": "Hurler's syndrome", "options": {"A": "Hurler's syndrome", "B": "Hunter's syndrome", "C": "Tay Sachs disease", "D": "Gaucher's disease", "E": "Fabry's disease"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the physician by her mother for a follow-up examination. She has a history of recurrent asthma attacks. The mother reports that her daughter has also had mild abdominal pain for the past 2 weeks. The patient's current medications include daily inhaled fluticasone and inhaled albuterol as needed. She appears well. Her temperature is 37°C (98.6°F), pulse is 100/min, and blood pressure is 130/85 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no murmurs, rubs, or gallops. Abdominal examination shows a left-sided, nontender, smooth abdominal mass that does not cross the midline. The remainder of the examination shows no abnormalities. A complete blood count and serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. Which of the following is the most likely diagnosis?", "answer": "Wilms' tumor", "options": {"A": "Polycystic kidney disease", "B": "Lymphoma", "C": "Wilms' tumor", "D": "Neuroblastoma", "E": "Renal cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old man with a history of hepatitis C infection presents to his physician because of unintentional weight loss and weakness. He has lost 6.8 kg (15 lb) within the last 6 months. Vital signs are within normal limits. Physical examination shows jaundice, splenomegaly, and caput medusae. A complete metabolic panel is ordered. Which of the following tests is the most likely to result in a diagnosis?", "answer": "Alanine aminotransferase", "options": {"A": "Alanine aminotransferase", "B": "Alkaline phosphatase", "C": "Aspartate aminotransferase", "D": "Blood urea nitrogen", "E": "Troponin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An investigator studying fungal growth isolates organisms from an infant with diaper rash. The isolate is cultured and exposed to increasing concentrations of nystatin. Selected colonies continue to grow and replicate even at high concentrations of the drug. Which of the following is the most likely explanation for this finding?", "answer": "Reduced ergosterol content in cell membrane", "options": {"A": "Reduced ergosterol content in cell membrane", "B": "Inactivation of cytosine permease", "C": "Mutation of the β-glucan gene", "D": "Altered binding site of squalene epoxidase", "E": "Expression of dysfunctional cytochrome P-450 enzymes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A rheumatologist is evaluating the long-term risk of venous thromboembolism in patients with newly diagnosed rheumatoid arthritis by comparing two retrospective cohort studies. In study A, the hazard ratio for venous thromboembolism was found to be 1.7 with a 95% confidence interval of 0.89–2.9. Study B identified a hazard ratio for venous thromboembolism of 1.6 with a 95% confidence interval of 1.1–2.5. Which of the following statements about the reported association in these studies is most accurate?", "answer": "The p-value of study A is likely larger than the p-value of study B.", "options": {"A": "The results of study B are less likely to be accurate than the results of study A.", "B": "The HR of study B is less likely to be statistically significant than the HR of study A.", "C": "Study A likely had a larger sample size than study B.", "D": "The p-value of study A is likely larger than the p-value of study B.", "E": "The power of study B is likely smaller than the power of study A."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old girl is brought into the clinic by her mother who is concerned that she may be depressed. The mother states that her daughter feels unattractive and does not fit into any of the social groups at school. When talking to the patient, it is discovered that she mostly avoids the kids in school because of fear of rejection. She usually keeps to herself and says she hasn’t involved herself in any group activities since elementary school. The patient’s mother is worried that this kind of behavior might continue or worsen if it progresses into her college years. Which of the following is the most likely diagnosis in this patient?", "answer": "Avoidant personality disorder", "options": {"A": "Avoidant personality disorder", "B": "Schizoid personality disorder", "C": "Social phobia", "D": "Dependent personality disorder", "E": "Body dysmorphic disorder"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 16-year-old female presents to her pediatrician complaining of 2 weeks of fever and 1 week of swollen lumps in her left armpit. Upon examination of the left upper extremity, her physician notes the presence of a single papule which the patient claimed appeared one week ago. The patient started her first job at a pet store 2.5 weeks ago. Which of the following is the vector of transmission of the causative agent?", "answer": "Cats", "options": {"A": "Animal urine", "B": "Cats", "C": "Parrots", "D": "Armadillos", "E": "Rabbits"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 63-year-old woman presents to her primary care provider with her spouse for routine follow-up. She has a history of schizophrenia and is currently living at a nursing facility. Her symptoms first started 2 years ago, when she developed auditory hallucinations and her family noticed that her thoughts and speech became more tangential and disorganized. After being referred to a psychiatrist, the patient was started on medication. Currently she reports occasional auditory hallucinations, but her spouse states that her symptoms have improved dramatically with medication. On exam, her temperature is 98.4°F (36.9°C), blood pressure is 110/74 mmHg, pulse is 64/min, and respirations are 12/min. The patient has normal affect with well-formulated, non-pressured speech. She denies any audiovisual hallucinations. Notably, however, the patient has repetitive lip-smacking behavior and occasionally sweeps her tongue across her lips. The spouse is curious about how this developed. Which of the following is the most likely medication this patient was started on?", "answer": "Haloperidol", "options": {"A": "Clozapine", "B": "Haloperidol", "C": "Olanzapine", "D": "Quetiapine", "E": "Risperidone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old G4P4 woman presents to her primary care physician complaining of a breast lump. She reports that she felt the lump while conducting a breast self-examination. Her past medical history is notable for endometrial cancer status post radical hysterectomy. She takes aspirin and fish oil. The patient drinks 3-4 alcoholic beverages per day and has a distant smoking history. Her temperature is 98.6°F (37°C), blood pressure is 130/75 mmHg, pulse is 90/min, and respirations are 18/min. A firm palpable mass in the upper outer quadrant of the right breast is noted on physical exam. Further workup reveals invasive ductal adenocarcinoma. She eventually undergoes radical resection and is started on a medication that is known to inhibit thymidylate synthetase. This patient is at increased risk for which of the following medication adverse effects?", "answer": "Photosensitivity", "options": {"A": "Peripheral neuropathy", "B": "Pulmonary fibrosis", "C": "Dilated cardiomyopathy", "D": "Ototoxicity", "E": "Photosensitivity"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old man is evaluated for progressive joint pain. There is swelling and tenderness over the first, second, and third metacarpophalangeal joints of both hands. His hand radiograph shows beak-like osteophytes on his 2nd and 3rd metacarpophalangeal joints, subchondral cysts, and osteopenia. He has had diabetes mellitus for 2 years which is not well controlled with medications. Lab studies show a transferrin saturation of 88% and serum ferritin of 1,200 ng/mL. This patient is at risk of which of the following complications?", "answer": "Hypogonadism", "options": {"A": "Hypogonadism", "B": "Hepatic adenoma", "C": "Hypertrophic cardiomyopathy", "D": "Hepatic steatosis", "E": "Cryoglobulinemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old woman is brought to the emergency department because of altered mental status for 2 hours. She and her husband were at the grocery store when she suddenly could not remember why she was there or how she got there. She has not had any head trauma. She has a history of depression and migraines. She does not smoke and drinks a glass of wine each night with dinner. She takes fluoxetine daily. She appears distressed and anxious. Her vital signs are within normal limits. She is fully alert and oriented to self and place but not to time. Every few minutes she asks how she got to the emergency department. She is able to follow commands and sustain attention. She recalls 3/3 objects immediately and recalls 0/3 objects at 5 minutes. The remainder of the neurological exam shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Transient global amnesia", "options": {"A": "Transient global amnesia", "B": "Depersonalization/derealization disorder", "C": "Seizure", "D": "Dissociative amnesia", "E": "Migraine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A team of biology graduate students are performing research on epigenetics and chromosome inactivation. The goal is to silence all the genes on a chromosome at once. The team chooses to develop a model based on a known human gene that can accomplish this task in vivo. Which of the genes listed below would be a suitable model for their research?", "answer": "XIST", "options": {"A": "SRY", "B": "XIST", "C": "Hox", "D": "Hedgehog", "E": "NF1"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old man presents to a physician with the complaint of a dry cough for the last 2 months. He denies any nasal discharge, sneezing, nose congestion, blood in sputum, breathlessness, fever, or weight loss. He started smoking 2 years back. His temperature is 37.3°C (99.2°F), the heart rate is 88/min, the blood pressure is 118/78 mm Hg, and the respiratory rate is 18/min. Auscultation of the lungs reveals localized rhonchi over the left infrascapular region. His chest radiogram reveals a single, round-shaped nodule with scalloped margins in the lower zone of the left lung. The nodule is surrounded by normally aerated lung tissue, and its size is approx. 9 mm (0.35 in) in diameter. The physician explains to him that he requires further diagnostic evaluation, as the nodule could be malignant. On the radiogram, which of the following features of the nodule is associated with the increased possibility of a malignant lesion?", "answer": "Lack of calcification", "options": {"A": "Lack of calcification", "B": "Dense central nidus of calcification", "C": "Multiple punctate foci of calcification throughout the nodule", "D": "Bull’s eye calcification", "E": "Popcorn ball calcification"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old man comes to the physician because of progressive pain, redness, and swelling of his left forearm. The symptoms began after he scratched his arm on a metal table 4 days ago. Examination of the left forearm shows a 2-cm, tender, erythematous, fluctuant lesion at the site of trauma. Incision and drainage of the lesion is performed and a small amount of thick, white liquid is expressed. Which of the following cytokines is involved in the recruitment of the primary cell type found in this liquid?", "answer": "IL-8", "options": {"A": "IL-11", "B": "IL-8", "C": "IL-2", "D": "IL-5", "E": "IL-14"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Your test subject is a stout 52-year-old gentleman participating in a study on digestion. After eating a platter of meat riblets and beef strips a test subjects digestive tract undergoes vast hormonal changes. Which of the following changes likely occurred in this patient as a result of the meal?", "answer": "Increased release of secretin from S cells of the duodenum", "options": {"A": "Increased gastrin release leading to a decrease in proton secretion", "B": "Decreased cholecystokinin release from the I cells of the duodenum", "C": "Increased release of secretin from S cells of the duodenum", "D": "Decreased Ach release from the vagus nerve", "E": "Increased release of ghrelin from P/D1 cells of the stomach"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year-old G1P0 woman at 25 weeks estimated gestational age presents with a blood pressure of 188/99 mm Hg during a routine prenatal visit. She has no symptoms, except for a mild headache. The patient's heart rate is 78/min. An injectable antihypertensive along with a beta-blocker is administered, and her blood pressure returns to normal within a couple of hours. She is sent home with advice to continue the beta-blocker. The patient returns after a couple of weeks with joint pain in both of her knees and fatigue. A blood test for anti-histone antibodies is positive. Which of the following is the mechanism of action of the intravenous antihypertensive medication most likely used in this patient?", "answer": "Interference with action of inositol trisphosphate (IP3) on intracellular calcium release", "options": {"A": "Calcium channel antagonism", "B": "Potassium channel activation", "C": "Release endogenous nitrous oxide", "D": "Inhibition of phosphodiesterase enzyme", "E": "Interference with action of inositol trisphosphate (IP3) on intracellular calcium release"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man presents with acute abdominal pain accompanied by chills, nausea, and vomiting. His past medical history is significant for benign prostatic hyperplasia and diabetes mellitus type 2. His medications are tamsulosin and metformin. His last HbA1c, 5 months ago, was 6.7. He had a screening colonoscopy 5 years ago which was normal. He denies blood in the stool or urine and has had no change in bowel habits. Throughout the encounter, the patient has difficulty getting comfortable on the exam table. His temperature is 38.2°C (100.7°F), the heart rate is 103/min, the respiratory rate is 15/min, and the blood pressure is 105/85 mm Hg. Physical exam is significant for left costovertebral angle tenderness. Peritoneal signs are absent. CBC, CMP, and urinalysis results are pending. Abdominal X-ray is shown. Which of the following is the next best step in management?", "answer": "Surgical removal and antibiotics", "options": {"A": "Observation with hydration, bed rest, and analgesics", "B": "Amlodipine", "C": "Antibiotics", "D": "Surgical removal and antibiotics", "E": "Urine alkalinization"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 74-year-old man returns to his physician to follow-up on laboratory studies obtained for anemia 2 weeks ago. He has no complaints. He has a 20-year history of hypertension and several years of knee osteoarthritis. He walks 2 miles a day. He does not smoke. He drinks alcohol moderately. He takes hydrochlorothiazide, losartan, and pain killers, including ibuprofen. The vital signs include: temperature 37.1°C (98.8°F), pulse 68/min, respiratory rate 12/min, and blood pressure 110/70 mm Hg. The physical examination shows no abnormalities. The laboratory studies show the following:\nLaboratory test\nHemoglobin 10 g/dL\nMean corpuscular volume 75 μm3\nLeukocyte count 5,000/mm3\nPlatelet count 350,000/mm3\nESR 18 mm/hr\nSerum\nFerritin 5 μg/L\nIron 30 μg/L\nTotal iron-binding capacity 500 μg/dL\nCalcium (Ca+) 9 mg/dL\nAlbumin 4 g/dL\nUrea nitrogen 14 mg/dL\nCreatinine 0.9 mg/dL\nMonoclonal protein on serum electrophoresis is 12 g/L (non-IgM). Clonal bone marrow plasma cells comprise 4% of the total number of cells. Skeletal survey with magnetic resonance imaging reveals no pathologic findings. In addition to iron deficiency anemia, which of the following diagnosis is most appropriate to consider?", "answer": "Monoclonal gammopathy of undetermined significance", "options": {"A": "Monoclonal gammopathy of undetermined significance", "B": "Smoldering (asymptomatic) multiple myeloma", "C": "Solitary plasmacytoma", "D": "Symptomatic multiple myeloma", "E": "Waldenstrom’s macroglobulinemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-year-old boy is brought to the physician because of fever, productive cough, and shortness of breath. Since birth, he has had multiple respiratory infections requiring treatment with antibiotics. His immunizations are up-to-date. He is in the 10th percentile for height and weight. His temperature is 38°C (100.3°F). Examination detects diffuse bilateral wheezing and cervical lymphadenopathy. Flow cytometric analysis of a serum sample from the patient fails to fluoresce after incubation with dihydrorhodamine. This patient is at greatest risk of infection with which of the following organisms?", "answer": "Serratia marcescens", "options": {"A": "Enterococcus faecium", "B": "Serratia marcescens", "C": "Streptococcus pneumoniae", "D": "Clostridioides difficile", "E": "Streptococcus pyogenes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman presented to the clinic for her first prenatal appointment with fatigue and pain in the perineum for the past 8 days. The past medical history is benign and she claimed to have only had unprotected intercourse with her husband. She had a documented allergic reaction to amoxicillin 2 years ago. The vaginal speculum exam revealed a clean, ulcerated genital lesion, which was tender and non-exudative. No lymphadenopathy was detected. A rapid plasma reagin (RPR) test revealed a titer of 1:64 and the fluorescent treponemal antibody absorption (FTA- abs) test was positive. What is the next best step in the management of this patient?", "answer": "Penicillin desensitization, then intramuscular benzathine penicillin, G 2.4 million units", "options": {"A": "Parenteral ceftriaxone, 1 g x 10 days", "B": "Penicillin desensitization, then intramuscular benzathine penicillin, G 2.4 million units", "C": "Oral tetracycline, 500 mg 4 times daily x 1 week", "D": "Doxycycline, 100 mg twice daily x 14 days", "E": "Delay treatment until delivery"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 63-year-old woman is brought to the emergency department by one of her neighbors because of fever and confusion. She has a 10-year history of diabetes mellitus and hemorrhoids. Her medications include insulin and metformin. Her blood pressure is 90/70 mm Hg, the pulse is 115/min, the respirations are 21/min, and the temperature is 39.5℃ (103.1℉). The cardiopulmonary examination shows no other abnormalities. The serum creatinine level is 2.5 mg/dL. An MRI shows swelling of subcutaneous soft tissue and gas. She is resuscitated with IV fluids. Broad-spectrum empiric IV antibiotics are administered. Which of the following is the most appropriate next step in management?", "answer": "Surgical debridement", "options": {"A": "Culture-based antibiotic therapy", "B": "High-dose IV steroids", "C": "Image-guided needle aspiration", "D": "Surgical debridement", "E": "No further management is indicated at this time"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 14-year-old boy is brought to the physician for evaluation because of loss of appetite, sleeplessness, and extreme irritability for 3 weeks. He recently quit the school's football team after missing many practices. He has also been avoiding his family and friends because he is not in the mood to see them but admits that he is lonely. He has not left his room for 2 days, which prompted his father to bring him to the physician. He has no medical conditions and does not take any medications. He does not drink alcohol or use recreational drugs. While the father is in the waiting room, mental status examination is conducted, which shows a constricted affect. Cognition is intact. He says that he would be better off dead and refuses to be treated. He says he wants to use his father's licensed firearm to “end his misery” over the weekend when his parents are at church. Which of the following is the most appropriate next step in management?", "answer": "Involuntary hospitalization after informing the parents", "options": {"A": "Involuntary hospitalization after informing the parents", "B": "Agree to his wish for no further treatment", "C": "Reassure the patient that he will feel better", "D": "Begin paroxetine therapy", "E": "Start outpatient psychotherapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 58-year-old man comes to the clinic complaining of increased urinary frequency for the past 3 days. The patient reports that he has had to get up every few hours in the night to go to the bathroom, and says \"whenever I feel the urge I have to go right away.” Past medical history is significant for a chlamydial infection in his twenties that was adequately treated. He endorses lower back pain and subjective warmth for the past 2 days. A rectal examination reveals a slightly enlarged prostate that is tender to palpation. What is the most likely explanation for this patient’s symptoms?", "answer": "Infection with Escherichia coli", "options": {"A": "Benign prostatic hyperplasia", "B": "Chemical irritation of the prostate", "C": "Infection with Escherichia coli", "D": "Prostatic adenocarcinoma", "E": "Reinfection with Chlamydia trachomatis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old woman presents with right eye irritation, redness, and watery discharge. These symptoms started abruptly 4 days ago. She is on summer vacation and does not report any contacts with evidently ill patients. However, during the vacation, she frequently visited crowded places. The patient denies any other symptoms. At the presentation, the patient’s vital signs include: blood pressure 125/80 mm Hg, heart rate 75/min, respiratory rate 14/min, and temperature 36.7℃ (98℉). The physical examination shows conjunctival injection, watery discharge, and mild follicular transformation of the conjunctiva of the right eye. There are no corneal lesions. Ipsilateral preauricular lymph nodes are enlarged. Which of the following would be a proper medical therapy for this patient", "answer": "No medical treatment required", "options": {"A": "Oral erythromycin", "B": "Acyclovir ointment", "C": "No medical treatment required", "D": "Levofloxacin drops", "E": "Tetracycline ointment"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old man presents with a 1-month history of frequent intermittent headaches. He says the headaches typically occur between 3–4 times/day, mostly at night, each lasting minutes to 1–2 hours. He describes the pain as severe, stabbing, unilateral, and localized to the left periorbital region. He says he frequently notes increased tear production and conjunctival injection in the left eye and rhinorrhea during these headaches. He mentions that he had a similar 3-week episode of these same, frequent intermittent headaches 3 months ago which stopped completely until 1 month ago. He denies any seizures, loss of consciousness, nausea, vomiting, photophobia, or phonophobia. His past medical history is significant for stable angina secondary to coronary artery disease diagnosed on a stress echocardiogram 1 year ago. He reports occasional alcohol use, which he says precipitates the headaches, but denies any smoking or recreational drug use. The patient is afebrile, and his vital signs are within normal limits. A physical examination is unremarkable. A noncontrast computed tomography (CT) scan of the head is normal. Which of the following is the best abortive treatment for this patient?", "answer": "High-flow 100% oxygen", "options": {"A": "Sumatriptan", "B": "Dihydroergotamine", "C": "High-flow 100% oxygen", "D": "Hydrocodone", "E": "Intranasal lidocaine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old man comes to the physician because of skin lesions on and around his anus. He noticed them 3 days ago. The lesions are not painful and he does not have any urinary complaints. He has smoked one pack of cigarettes daily for 10 years and he drinks 6–7 beers on weekends. He is sexually active with two male partners and uses condoms inconsistently. He appears healthy. A photograph of the perianal region is shown. The lesions turn white after application of a dilute acetic acid solution. The remainder of the examination shows no abnormalities. An HIV test is negative. Which of the following is the most appropriate next step in management?", "answer": "Curettage", "options": {"A": "Oral acyclovir", "B": "Topical mometasone", "C": "Radiotherapy", "D": "Parenteral benzathine penicillin", "E": "Curettage"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 28-year-old woman presents with severe diarrhea and abdominal pain. She says she has had 10 watery stools since the previous morning and is experiencing severe cramping in her abdomen. She reports similar past episodes of diarrhea with excruciating abdominal pain and mentions that she has taken diphenoxylate and atropine before which had helped her diarrhea and pain but resulted in severe constipation for a week. Which of the following receptors does diphenoxylate activate to cause the effects mentioned by this patient?", "answer": "µ receptor", "options": {"A": "NK1 receptor", "B": "H2 receptor", "C": "5-HT3 receptor", "D": "D2 receptor", "E": "µ receptor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman comes to the physician because of poor balance and recurrent falls for the past month. She has also had blurry vision in her right eye for the past 2 weeks. She reports worsening of her symptoms after taking warm baths. Physical examination shows generalized hyperreflexia and an intention tremor. Romberg sign is positive. Visual acuity is 20/50 in the left eye and 20/100 in the right eye, and she is unable to distinguish red from green colors. The cells primarily affected by this patient's condition are most likely derived from which of the following embryologic structures?", "answer": "Neuroectoderm", "options": {"A": "Mesoderm", "B": "Endoderm", "C": "Neuroectoderm", "D": "Neural crest", "E": "Notochord"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-year-old boy is brought to the emergency department for a right ankle injury sustained during a fall earlier that morning. His parents report that he is 'clumsy' when he runs and has fallen multiple times in the last year. He has reached most of his developmental milestones but did not walk until the age of 17 months. He is an only child and was adopted at age 1. He appears tearful and in mild distress. His temperature is 37.2°C (98.9°F), pulse is 72/min, respirations are 17/min, and blood pressure is 80/50 mm Hg. His right ankle is mildly swollen with no tenderness over the medial or lateral malleolus; range of motion is full with mild pain. He has marked enlargement of both calves. Patellar and Achilles reflexes are 1+ bilaterally. Strength is 4/5 in the deltoids, knee flexors/extensors, and 5/5 in the biceps and triceps. Babinski sign is absent. When standing up from a lying position, the patient crawls onto his knees and slowly walks himself up with his hands. Which of the following is the most likely underlying mechanism of this patient's condition?", "answer": "Absence of dystrophin protein", "options": {"A": "SMN1 gene defect", "B": "Loss of the ATM protein", "C": "Myotonin protein kinase defect", "D": "Absence of dystrophin protein", "E": "Arylsulfatase A deficiency"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A group of 6 college students with multiple sclerosis (MS) was evaluated for flares in a neurology clinic. The results are shown in the figure. Each row represents a patient. The gray bars represent the duration of the flare. The arrowheads indicate that disease was already present before and/or persisted beyond the timeframe of the study. Based on the figure, which of the following is the most valid statement about MS flares in this group of students?", "answer": "Incidence during the month of May was 2", "options": {"A": "Incidence from April 1st to June 1st was 3", "B": "Incidence during the month of May was 2", "C": "Incidence during the month of February was 3", "D": "The year-long prevalence was 4/6", "E": "Prevalence of the disease on May 15 was 4/6"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 33-year-old man presents to the emergency department with sudden onset right hand and right leg weakness. The patient was at home cleaning when his symptoms began. He also complains of diffuse and severe pain throughout his entire body which he states he has experienced before. The patient is an immigrant from South America, and his medical history is not known. His temperature is 98.9°F (37.2°C), blood pressure is 128/67 mmHg, pulse is 80/min, respirations are 16/min, and oxygen saturation is 99% on room air. CT of the head demonstrates no bleeding. Physical exam is notable for 2/5 strength in the patient's right arm and right leg. Which of the following is the best management in this patient?", "answer": "Exchange transfusion", "options": {"A": "Aspirin", "B": "Exchange transfusion", "C": "Heparin", "D": "Morphine and IV fluids", "E": "Tissue plasminogen activator"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old man presents to his primary care physician because he has been experiencing constipation for the last 6 days. He says that the constipation started 1 day after he started taking an over the counter medication for sinus congestion and a chronic cough. He has no other findings associated with the constipation. His past medical history is significant for seasonal allergies but he is not currently taking any other medications besides the one he reported. Which of the following drugs was most likely responsible for this patient's symptoms?", "answer": "Dextromethorphan", "options": {"A": "Dextromethorphan", "B": "Diphenhydramine", "C": "Guaifenesin", "D": "Loratadine", "E": "N-acetylcysteine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman follows up at an outpatient surgery clinic with an abnormal scarring of her incisional wound from an abdominal surgical procedure  6 months ago. She gives a history of a wound infection with a purulent discharge 1 week after surgery. On examination of the scar, a dense, raised, healed lesion is noted at the incision site. She also complains of an occasional itching sensation over the scar. There is no history of such scar changes in her family. An image of the lesion is given below. Which of the following statements best describe the scar abnormality?", "answer": "There is excessive scar tissue projecting beyond the level of the surrounding skin, but not extending into the underlying subcutaneous tissue.", "options": {"A": "The scar has hair follicles and other adnexal glands within.", "B": "There is excessive scar tissue projecting beyond the level of the surrounding skin, but not extending into the underlying subcutaneous tissue.", "C": "This type of scar does not have claw-like projections.", "D": "Increased prevalence of this type of scar has no genetic basis or linkage.", "E": "This scar tissue is limited within the borders of the traumatized area."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "You are attempting to quantify the degree of infectivity of a novel respiratory virus. You assess 1,000 patients who have been exposed to the virus and find that 500 ultimately are found positive for the virus within a 1-year follow up period. Conversely, from a 1,000 patient control group who has not been exposed to carriers of the virus, only 5 became positive over the same 1-year period. What is the relative risk of a contracting this virus if exposed?", "answer": "[500/ (500 + 500)] / [5 / (5 + 995)]", "options": {"A": "[5 / (500 + 500)] / [5 / (995 + 995)]", "B": "[995 / (995 + 5)] / [500 / (500 + 500)]", "C": "[500/ (500 + 500)] / [5 / (5 + 995)]", "D": "(500 * 995) / (500 * 5)", "E": "(500 * 5) / (500 * 995)"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 19-year-old man comes to the physician because of recurrent yellowing of his eyes over the past 2 years. He reports that each episode lasts 1–2 weeks and resolves spontaneously. He has no family history of serious illness. He recently spent a week in Mexico for a vacation. He is sexually active with two partners and uses condoms inconsistently. He does not drink alcohol or use illicit drugs. His vital signs are within normal limits. Physical examination shows jaundice of the conjunctivae and the skin. The abdomen is soft with no organomegaly. The remainder of the physical examination shows no abnormalities. Laboratory studies show:\nSerum\nTotal bilirubin 4.0 mg/dL\nDirect bilirubin 3.0 mg/dL\nAlkaline phosphatase 75 U/L\nAST 12 U/L\nALT 12 U/L\nAnti-HAV IgG positive\nHBsAg negative\nAnti-HBsAg positive\nHCV RNA negative\nUrine\nBilirubin present\nUrobilinogen normal\nWhich of the following is the most likely underlying cause of this patient's condition?\"", "answer": "Impaired hepatic storage of bilirubin", "options": {"A": "Destruction of the intralobular bile ducts", "B": "Inflammation of intra- and extrahepatic bile ducts", "C": "Impaired hepatic storage of bilirubin", "D": "Excess cellular bilirubin release", "E": "Defective bilirubin conjugation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 49-year-old man presents to his primary care provider complaining of weakness and fatigue. He reports that he has started moving slower than normal and has noticed difficulty buttoning up his pants or tying his tie. He is accompanied by his wife who reports that he has started to move more slowly over the past 2 years. He has also become increasingly irritable and has had trouble sleeping. His past medical history is notable for hypertension, diabetes mellitus, and obesity. He takes enalapril and metformin. His family history is notable for multiple strokes in his mother and father. His temperature is 99°F (37.2°C), blood pressure is 140/90 mmHg, pulse is 90/min, and respirations are 17/min. On exam, strength is 4+/5 bilaterally in his upper extremities and 4/5 in his lower extremities. Some muscle atrophy is noted in his legs and feet. Patellar reflexes are 3+ bilaterally. He has a tremor in his right hand that diminishes when he is instructed to hold a pen in his hand. He is oriented to person, place and time. He states that he feels depressed but denies suicidal ideation. His physician prescribes multiple medications including a drug that is also indicated in the treatment of prolactinomas. Which of the following is the mechanism of action of this medication?", "answer": "Activate dopamine receptors", "options": {"A": "Activate dopamine receptors", "B": "Increase dopamine release", "C": "Inhibit dopamine receptors", "D": "Prevent dopamine degradation into 3,4-dihydroxyphenylacetic acid", "E": "Prevent dopamine degradation into 3-O-methyldopa"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 1-year-old boy is brought to his pediatrician for a follow-up appointment. He was recently diagnosed with failure to thrive and developmental delay. His weight is 7 kg (15.4 lb), height is 61 cm (24 in), and head circumference is 42 cm (16.5 in). The patient’s father had a younger sister who suffered from mental and physical delay and died at a very young age. The patient was able to raise his head at the age of 7 months and began to sit alone only recently. He babbles, coos, and smiles to other people. On presentation, his blood pressure is 75/40 mm Hg, heart rate is 147/min, respiratory rate is 28/min, and temperature is 36.4°C (97.5°F). He has a coarse face with small deep orbits, proptotic eyes, big lips, and gingival hyperplasia. His skin is pale with decreased elasticity. His lung and heart sounds are normal. Abdominal examination reveals diminished anterior abdominal wall muscle tone and hepatomegaly. Muscle tone is increased in all groups of muscles on both upper and lower extremities. The physician becomes concerned and performs testing for the suspected hereditary disease. A blood test shows increased lysosomal enzyme concentration in the serum and decreased N-acetylglucosamine-1-phosphotransferase (GlcNAc phosphotransferase) activity within the leukocytes. Which of the statements listed below describes the mechanism of the patient’s condition?", "answer": "The lysosomal enzymes are secreted from the cells instead of being targeted to lysosomes because of lack of mannose phosphorylation on N-linked glycoproteins.", "options": {"A": "The patient’s symptoms are due to dysfunctional metabolism of sphingomyelin, which accumulates within the lysosomes.", "B": "There is impaired hydrolysis of GM2-ganglioside, which accumulates in the cytoplasm.", "C": "The lysosomal enzymes are secreted from the cells instead of being targeted to lysosomes because of lack of mannose phosphorylation on N-linked glycoproteins.", "D": "Due to enzyme deficiency, glycogen is extensively accumulated within the hepatocytes.", "E": "The symptoms result from defective glycolysis, which results in a total energy deficiency."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 13-year-old girl presents with a right infected ingrown toenail. On examination, the skin on the lateral side of the toe is red, warm, swollen, and severely tender to touch. When gentle pressure is applied, pus oozes out. Culture and sensitivity analysis of the pus shows methicillin-resistant Staphylococcus aureus (MRSA). Which of the following antibiotics is most effective against this organism?", "answer": "Clindamycin", "options": {"A": "Cefotetan", "B": "Oral vancomycin", "C": "Clindamycin", "D": "Cefuroxime", "E": "Aztreonam"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 39-year-old man comes to the physician for a follow-up examination. He was diagnosed with latent tuberculosis infection 3 months ago. He has had generalized fatigue and dyspnea on exertion for the past 6 weeks. He does not smoke and drinks 2–3 beers on weekends. Vital signs are within normal limits. Examination shows conjunctival pallor. Laboratory studies show:\nHemoglobin 7.8 g/dL\nMean corpuscular volume 72 μm3\nRed cell distribution width 17% (N = 13–15)\nReticulocyte count 0.7%\nLeukocyte count 6,800/mm3\nPlatelet count 175,000/mm3\nSerum\nCreatinine 0.8 mg/dL\nIron 246 μg/dL\nFerritin 446 ng/mL\nTotal iron-binding capacity 212 μg/dL (N = 250–450)\nWhich of the following is the most likely cause of this patient's symptoms?\"", "answer": "Adverse effect of medication", "options": {"A": "Iron deficiency", "B": "Chronic inflammation", "C": "Beta thalessemia minor", "D": "Adverse effect of medication", "E": "Vitamin B12 deficiency\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 33-year-old woman comes to the physician for a follow-up examination. She was treated for a urinary stone 1 year ago with medical expulsive therapy. There is no personal or family history of serious illness. Her only medication is an oral contraceptive pill that she has been taking for 12 years. She appears healthy. Physical examination shows no abnormalities. A complete blood count, serum creatinine, and electrolytes are within the reference range. Urinalysis is within normal limits. An ultrasound of the abdomen shows a well-demarcated hyperechoic 3-cm (1.2-in) hepatic lesion. A contrast-enhanced CT of the abdomen shows a well-demarcated 3-cm hepatic lesion with peripheral enhancement and subsequent centripetal flow followed by rapid clearance of contrast. There is no hypoattenuating central scar. In addition to stopping the oral contraceptive pill, which of the following is the most appropriate next step in management?", "answer": "Reimage in 6 months", "options": {"A": "Embolization of the mass", "B": "Percutaneous liver biopsy", "C": "Reimage in 6 months", "D": "Radiofrequency ablation of the mass", "E": "Surgical resection of the mass"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 73-year-old man is brought to the emergency department because of fever, malaise, dyspnea, and a productive cough with purulent sputum for the past day. His temperature is 39.2°C (102.6°F). Pulmonary examination shows crackles over the right upper lung field. Sputum Gram stain shows gram-positive cocci. Despite the appropriate treatment, the patient dies 5 days later. At autopsy, gross examination shows that the right lung has a pale, grayish-brown appearance and a firm consistency. Microscopic examination of the tissue is most likely to show which of the following?", "answer": "Fibrinopurulent leukocytic exudate with lysed erythrocytes", "options": {"A": "Fibrinopurulent leukocytic exudate with lysed erythrocytes", "B": "Fibrinous exudate with erythrocytes, leukocytes, and bacteria", "C": "Resorbed exudate with aerated alveoli", "D": "Neutrophilic infiltrate in the bronchiolar walls and adjacent alveoli", "E": "Dilation of alveolar capillaries and serous exudate with abundant bacteria"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman presents to the clinic with a runny nose and productive cough for the past two weeks. She also complains of headaches and lethargy. She was started on sertraline after she was diagnosed with major depressive disorder 2 months ago and had the dosage periodically increased to achieve symptom control. She is afraid of starting any other medication because of possible side-effects or life-threatening drug interactions. What advice is the most accurate regarding possible complication to her current pharmacotherapy?", "answer": "Migraine medication can trigger a life-threatening complication.", "options": {"A": "Migraine medication can trigger a life-threatening complication.", "B": "Sertraline cannot be used concurrently with neuroleptics", "C": "Monoamine-oxidase-inhibitors are safe for concurrent use.", "D": "Over-the-counter (OTC) medications are safe for her to use.", "E": "Treat life-threatening complication with gradual drug withdrawal."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old man presents to the office, complaining of a rash and “not feeling well.” The patient reports fatigue, a headache, and a possible fever. He says he has felt this way since a camping trip with his family in North Carolina, but he denies any contact with sick individuals. On examination, his vital signs include: temperature 38.5°C (101.3°F), blood pressure 100/60 mm Hg, heart rate 82 beats per minute, respiratory rate 14 breaths per minute, and O2 saturation 99% on room air. The patient appears unwell. He has a maculopapular rash on his upper and lower extremities, including the palms of his hands and soles of his feet. He says he started feeling sick a few days before he got the rash, which prompted him to come into the office. The patient denies itching but admits to some nausea and vomiting. He also admits to unprotected sex with a single female partner for the past three years. What is the most likely causative agent of this patient’s presentation?\n ", "answer": "A gram-negative bacteria transmitted via the Dermacentor tick", "options": {"A": "A sexually transmitted spirochete", "B": "A protozoan transmitted via the Ixodes tick", "C": "A gram-negative bacteria transmitted via the Dermacentor tick", "D": "A gram-negative bacterium transmitted via the Ixodes tick", "E": "A positive-sense, single-stranded RNA virus that is non-enveloped"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 67-year-old man presents to the emergency department with anxiety and trouble swallowing. He states that his symptoms have slowly been getting worse over the past year, and he now struggles to swallow liquids. He recently recovered from the flu. Review of systems is notable only for recent weight loss. The patient has a 33 pack-year smoking history and is a former alcoholic. Physical exam is notable for poor dental hygiene and foul breath. Which of the following is the most likely diagnosis?", "answer": "Squamous cell carcinoma", "options": {"A": "Achalasia", "B": "Globus hystericus", "C": "Squamous cell carcinoma", "D": "Viral-induced gastroparesis", "E": "Zenker diverticulum"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A group of scientists studied the effects of cytokines on effector cells, including leukocytes. They observed that interleukin-12 (IL-12) is secreted by antigen-presenting cells (APCs) in response to bacterial lipopolysaccharide. When a CD4+ T cell is exposed to this interleukin, which of the following responses will it have?", "answer": "Cell-mediated immune responses", "options": {"A": "Cell-mediated immune responses", "B": "Activate B cells", "C": "Secrete IL–4", "D": "Releases granzymes", "E": "Responds to extracellular pathogens"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old woman presents with a whitish vaginal discharge over the last week. She also complains of itching and discomfort around her genitals. She says her symptoms are getting progressively worse. She has been changing her undergarments frequently and changed the brand of detergent she uses to wash her clothes, but it did not resolve her problem. Additionally, she admits to having painful urination and increased urinary frequency for the past one month, which she was told are expected side effects of her medication. The patient denies any recent history of fever or malaise. She has 2 children, both delivered via cesarean section in her late twenties. Past medical history is significant for hypertension and diabetes mellitus type 2. Current medications are atorvastatin, captopril, metformin, and empagliflozin. Her medications were changed one month ago to improve her glycemic control, as her HbA1c at that time was 7.5%. Her vital signs are a blood pressure of 126/84 mm Hg and a pulse of 78/min. Her fingerstick glucose is 108 mg/dL. Pelvic examination reveals erythema and mild edema of the vulva. A thick, white, clumpy vaginal discharge is seen. The vaginal pH is 4.0. Microscopic examination of a KOH-treated sample of the discharge demonstrates lysis of normal cellular elements with branching pseudohyphae. Which of the following is the next best step in the management of this patient?", "answer": "Start fluconazole.", "options": {"A": "Start metronidazole.", "B": "Stop empagliflozin.", "C": "Advise her to drink lots of cranberry juice.", "D": "Switch her from oral antidiabetic medication to insulin.", "E": "Start fluconazole."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 44-year-old female patient comes to the physician’s office with her husband with complaints of abdominal pain. For the past 4 months, she has experienced cramping right upper quadrant pain that starts after meals. The physician performs a right upper quadrant ultrasound that shows round echogenic masses in the gallbladder. The physician offers an elective cholecystectomy to the patient to improve her symptoms and explains the procedure in detail to the patient including potential risks and complications. The patient acknowledges and communicates her understanding of her diagnosis as well as the surgery and decides to proceed with the surgery in one month. The patient signs a form indicating her consent to this procedure. Which of the following must also be communicated to the patient at this time?", "answer": "The patient has the right to revoke her consent at any time before the procedure", "options": {"A": "A family member must also provide consent for this procedure", "B": "The patient must give consent again before the procedure", "C": "The patient has the right to revoke her consent at any time before the procedure", "D": "The patient’s consent was not necessary for this procedure", "E": "The results of the procedure must be disclosed to her husband"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A patient presents to the clinic with symptoms of dizziness on standing up. He says it started soon after he was diagnosed with hypertension and started taking treatment for it. He has no other medical history. The physician decides to switch to another antihypertensive that does not cause orthostatic hypotension. Which of the following should be the drug of choice for this patient?", "answer": "Propanolol", "options": {"A": "Enalapril", "B": "Methyldopa", "C": "Clonidine", "D": "Amlodipine", "E": "Propanolol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old woman comes to the physician with a 6-month history of breast tenderness and menstrual irregularities. Physical examination shows no abnormalities. An ultrasound of the pelvis shows a right adnexal mass. A laparoscopic right salpingo-oophorectomy is performed. Histologic examination of the adnexal mass shows small cuboidal cells arranged in clusters surrounding a central cavity with eosinophilic secretions. These cells resemble primordial follicles. Which of the following laboratory values was most likely increased in this patient at the time of presentation?", "answer": "Estradiol", "options": {"A": "Estradiol", "B": "Lactate dehydrogenase", "C": "α-fetoprotein", "D": "β-human chorionic gonadotropin", "E": "Follicle stimulating hormone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 50-year-old man presents to the emergency department complaining of chest pain and drooling that started immediately after eating a steak. His past medical history is significant for lye ingestion 5 years ago during a suicidal attempt. He also suffers from hypertension and diabetes mellitus, type 2. He takes fluoxetine, lisinopril, and metformin every day. He also regularly sees a counselor to cope with his previous suicide attempt. Both of his parents are still alive and in good health. His heart rate is 96/min, temperature is 36.7°C (98.1°F).On physical examination, the patient can talk normally and breaths without effort. He is drooling. The chest pain is vague and constant. A chest X-ray shows no subcutaneous emphysema. An endoscopy confirms the presence of a retained bolus of meat 24 cm beyond the incisors where a stricture is identified. The bolus is removed and the stricture is dilated. Which of the following anatomic spaces contains the stricture?", "answer": "The superior mediastinum", "options": {"A": "The superior mediastinum", "B": "The diaphragm", "C": "The anterior mediastinum", "D": "The posterior mediastinum", "E": "The epigastrium"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old man presents with a chief complaint of pain in the great toe. He has a history of gout, which is under control. He was diagnosed with diabetes 5 years ago and is currently taking metformin. He was recently diagnosed with hypertension and was placed on a hypertensive drug. He is a non-smoker and does not abuse alcohol. The family history is significant for ischemic heart disease in his father. His current blood pressure is 136/84 mm Hg and the pulse is 78/min. The physical examination did not reveal any abnormalities. He uses over-the-counter multivitamin supplements. Which of the following drugs could have resulted in these symptoms?", "answer": "Thiazide diuretics", "options": {"A": "Angiotensin II receptor blockers (ARBs)", "B": "Thiazide diuretics", "C": "Calcium channel blockers (CCBs)", "D": "Angiotensin-converting enzyme (ACE) inhibitors", "E": "Beta-blockers"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old girl is brought to the physician for a school physical examination. She feels well. She is performing well in school and getting good grades. She is 147 cm (4 ft 10 in) tall and weighs 60 kg (132 lbs); BMI is 27.6 kg/m2. Her temperature is 37°C (98.6°F), pulse is 82/min, respirations are 16/min, and blood pressure is 138/82 mm Hg in the left arm and 110/74 mm Hg in the left leg. Physical examination shows an unusually short and broad neck with bilateral excess skin folds that extend to the shoulders and low-set ears. There is an increased carrying angle when she fully extends her arms at her sides. An x-ray of the chest shows inferior rib notching. Which of the following additional findings is most likely in this patient?", "answer": "Streak ovaries on pelvic ultrasound\n\"", "options": {"A": "Horseshoe adrenal gland on abdominal CT", "B": "Prolonged activated partial thromboplastin time", "C": "Uterine agenesis on pelvic exam", "D": "Mutation of FBN1 on genetic testing", "E": "Streak ovaries on pelvic ultrasound\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old woman, gravida 2, para 1, at 32 weeks' gestation comes to the physician for a prenatal visit. She feels that her baby's movements have decreased recently. She says that she used to feel 10–12 movements/hour earlier, but that it has recently decreased to about 7–8/hour. Pregnancy and delivery of her first child were uncomplicated. Medications include folic acid and a multivitamin. Her temperature is 37.2°C (99°F), and blood pressure is 108/60 mm Hg. Pelvic examination shows a uterus consistent in size with a 32-week gestation. The fetus is in a transverse lie presentation. The fetal heart rate is 134/min. A 14-minute recording of the nonstress test is shown. Which of the following is the most appropriate next step in managing this patient?", "answer": "Provide reassurance to the mother", "options": {"A": "Repeat the nonstress test weekly", "B": "Provide reassurance to the mother", "C": "Administer intravenous oxytocin", "D": "Perform vibroacoustic stimulation", "E": "Extend the nonstress test by 20 minutes"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "А 41-уеаr-old woman рrеѕеnts to thе offісе wіth a сomрlаіnt of а hеаdасhе for 1 month and a еріѕodе of аbnormаl bodу movеmеnt. The headaches are more severe іn thе mornіng, moѕtlу after waking up. Ѕhе doеѕn’t give a history of any mајor іllnеѕѕ or trauma in the past. Неr vіtаlѕ ѕіgnѕ include: blood рrеѕѕurе 160/80 mm Нg, рulѕе 58/mіn, tеmреrаturе 36.5°C (97.8°F), аnd rеѕріrаtorу rаtе 11/mіn. Оn fundoscopic ехаmіnаtіon, mіld раріllеdеmа is present. Her рuріlѕ аrе еquаl аnd rеасtіvе to lіght. No foсаl nеurologісаl dеfісіt сan bе еlісіtеd. A contrast computed tomography scan of the head is shown in the picture. Which of the following is the most likely biopsy finding in this case?", "answer": "Spindle cells concentrically arranged in whorled pattern with laminated calcification", "options": {"A": "Oligodendrocytes with round nuclei and clear surrounding cytoplasm giving a fried-egg appearance", "B": "Closely arranged thin walled capillaries with minimal intervening parenchyma", "C": "Pseudopalisading pleomorphic tumor cells", "D": "Spindle cells concentrically arranged in whorled pattern with laminated calcification", "E": "Large quantities of lymphocytes without a particular growth pattern"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old woman has complaints of dyspnea, cough, and arthritis in her ankle joints. A CT scan reveals multiples granulomas in both lungs, as well as bilateral hilar lymphadenopathy. On examination, cutaneous nodules over the trunk are found. Erythrocyte sedimentation rate, angiotensin-converting enzyme, and serum calcium levels are elevated. She is treated with steroids. What is the most likely diagnosis?", "answer": "Sarcoidosis", "options": {"A": "Hodgkin's lymphoma", "B": "Tuberculosis", "C": "Silicosis", "D": "Adenocarcinoma of the lung", "E": "Sarcoidosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A cell biologist is studying the activity of a novel chemotherapeutic agent against a cancer cell line. After incubation with the agent and cell detachment from the tissue culture plate, the DNA is harvested from the cells and run on a gel. Of note, there are large bands at every multiple of 180 base pairs on the gel. Which of the following explains the pathophysiology of this finding?", "answer": "Caspase activation", "options": {"A": "ATP depletion", "B": "Caspase activation", "C": "Cellular swelling", "D": "Protein denaturation", "E": "Release of lysosomal enzymes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-week-old newborn is brought to the physician because of worsening feeding difficulty since birth. Examination shows a grade 2/6 harsh holosystolic murmur, heard most clearly at the left lower sternal border, and a soft mid-diastolic rumble over the cardiac apex. Echocardiography shows shunting of blood through the ventricular septum during systole. The patient undergoes surgery for closure of the defect. Which of the following sets of changes are expected after successful repair of this cardiac defect?\n $$$ Left atrial pressure %%% Left ventricular pressure %%% Right ventricular pressure $$$", "answer": "↓ ↑ ↓", "options": {"A": "↓ ↑ no change", "B": "↓ ↑ ↓", "C": "↑ ↑ ↑", "D": "↓ ↓ ↓", "E": "↑ ↑ ↓"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 77-year-old man with a history of advanced dementia, hypertension, Parkinson’s disease, and diabetes mellitus type 2 is brought to the hospital from a nursing home after several days of non-bloody diarrhea and vomiting. The patient is evaluated and admitted to the hospital. Physical examination shows a grade 2/6 holosystolic murmur over the left upper sternal border, clear lung sounds, a distended abdomen with normal bowel sounds, a resting tremor, and 2+ edema of the lower extremities up to the ankle. Over the next few hours, the nurse records a total of 21 cc of urine output over the past 5 hours. Which of the following criteria suggest pre-renal failure?", "answer": "Fractional excretion of sodium of 0.5%", "options": {"A": "Urine osmolarity of 280 mOsm/kg", "B": "Urine Na of 80 mEq/L", "C": "Urine/plasma creatinine ratio of 10", "D": "Fractional excretion of sodium of 0.5%", "E": "Urine/plasma osmolarity ratio of 0.8"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to the physician by his mother because of a 2-week history of intermittent shortness of breath and a dry cough that is worse at night. He had an upper respiratory tract infection 3 weeks ago. Lungs are clear to auscultation. Spirometry shows normal forced vital capacity and peak expiratory flow rate. The physician administers a drug, after which repeat spirometry shows a reduced peak expiratory flow rate. Which of the following drugs was most likely administered?", "answer": "Methacholine", "options": {"A": "Atenolol", "B": "Methacholine", "C": "Ipratropium bromide", "D": "Methoxyflurane", "E": "Epinephrine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "А 42-уеаr-old woman рrеѕеntѕ wіth fасіаl аѕуmmеtrу. The patient says yesterday she noticed that her face appeared to be dеvіаted to the rіght. Ѕhе dеnіеѕ аnу trаumа or rесеnt trаvеl. Неr раѕt mеdісаl hіѕtorу іѕ nonсontrіbutorу. Her vitals are blood pressure 110/78 mm Hg, temperature 36.5°C (97.8°F), pulse 78/min, and respiratory rate 11/min. Оn рhуѕісаl ехаmіnаtіon, thеrе іѕ drooріng of thе left ѕіdе of thе fасе. Тhе left nаѕolаbіаl fold іѕ аbѕеnt, аnd ѕhе іѕ unаblе to сloѕе hеr left еуе or wrinkle thе left ѕіdе of hеr forеhеаd. Whеn the patient аѕkеd to ѕmіlе, thе resulting аѕуmmеtrу is shown in the given photograph. The remainder of the nеurologіс ехаm іѕ normаl. A noncontrast CT scan of the head is unremarkable. Which of the following is the most likely cause of her presentation?", "answer": "Idiopathic", "options": {"A": "Varicella-Zoster infection", "B": "Lyme disease", "C": "Idiopathic", "D": "Cerebrovascular accident", "E": "Malignancy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "You are the intern on the labor and delivery floor. Your resident asks you to check on the patient in Bed 1. She is a 27-year-old prima gravida with no significant past medical history. She has had an uncomplicated pregnancy and has received regular prenatal care. You go to her bedside and glance at the fetal heart rate tracing (Image A). What is the most likely cause of this finding?", "answer": "Fetal head compression", "options": {"A": "Fetal head compression", "B": "Utero-placental insufficiency", "C": "Cord compression", "D": "Fetal distress", "E": "Congenital heart block"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old woman presents to her primary care provider with an unrelenting headache accompanied by fever, chills, and malaise for the past 4 days. She also complains of an earache and dry hacking cough. Past medical history is noncontributory. She takes oral contraceptives and a multivitamin with calcium daily. She drinks alcohol socially and smokes occasionally. Today, her temperature is 37.9°C (100.2°F), pulse is 104/min, respiratory rate is 20/min and blood pressure is 102/82 mm Hg. On physical exam, she appears uncomfortable, but not ill. Her heart rate is elevated with a regular rhythm and her lungs have mild rhonchi in the lower lobes bilaterally. A chest X-ray shows patchy, diffuse infiltrates of the interstitium bilaterally that is worse in the lower lobes. A sputum culture is taken for stereomicroscopy. The pathogen organism appears small, pleomorphic, and lacks a cell wall. Which of the following is the most likely pathogen?", "answer": "Mycoplasma pneumonia", "options": {"A": "Streptococcus pneumonia", "B": "Legionella pneumophila", "C": "Staphylococcus pneumonia", "D": "Mycoplasma pneumonia", "E": "Haemophilus influenza"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "One day after doctors helped a 28-year-old primigravid woman deliver a 4,700 g (10 lb 6 oz) boy, the newborn has bluish discoloration of the lips and fingernails. His temperature is 37.3°C (99.1°F), the pulse is 166/min, the respirations are 63/min, and the blood pressure is 68/44 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 81%. Examination shows central cyanosis. A grade 2/6 holosystolic murmur is heard over the left lower sternal border. A single second heart sound is present. Supplemental oxygen does not improve cyanosis. An X-ray of the chest shows an enlarged cardiac silhouette with a narrowed mediastinum. Which of the following cardiac defects would be associated with this newborn’s diagnosis?", "answer": "Ventricular septal defect", "options": {"A": "Alignment of infundibular septum", "B": "Division of aorta and pulmonary artery", "C": "Fusion of endocardial cushion", "D": "Separation of tricuspid valve tissue from myocardium", "E": "Ventricular septal defect"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 44-year-old woman is admitted after an episode of dizziness and palpitations with a subsequent loss of consciousness. At the time of admission, the patient is alert, but then quickly becomes lethargic and reports reoccurrence of palpitations. Past medical history is significant for an episode of ventricular tachycardia 4 months ago, now managed with pharmacologic antiarrhythmic prophylaxis. An ECG is obtained and is shown on the image. Which of the following antiarrhythmic drugs below is most likely responsible for this patient's condition?", "answer": "Sotalol", "options": {"A": "Lidocaine", "B": "Sotalol", "C": "Propranolol", "D": "Verapamil", "E": "Diltiazem"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 62-year-old woman presents to the clinic with a lacerated wound on her left forearm. She got the wound accidentally when she slipped in her garden and scraped her hand against some nails sticking out of the fence. The patient has rheumatoid arthritis and takes methylprednisolone 16 mg/day. She cannot recall her vaccination history. On physical examination her blood pressure is 140/95 mm Hg, heart rate is 81/min, respiratory rate is 16/min, and temperature is 36.9°C (98.4°F). The wound is irregularly shaped and lacerated and measures 4 × 5 cm with a depth of 0.5 cm. It is contaminated with dirt. The physician decides to administer both the tetanus toxoid and immunoglobulin after wound treatment. What is true regarding the tetanus prophylaxis in this patient?", "answer": "The immunoglobulin administration will provide sufficient levels of anti-tetanus toxin antibodies until the production of the patient’s own antibodies starts.", "options": {"A": "It does not make sense to administer tetanus toxoid as it will fail to induce sufficient immunity in a patient who takes oral glucocorticoids.", "B": "The immunoglobulin is given to this patient to promote the action of the toxoid and antibody production.", "C": "The immunoglobulin administration will provide sufficient levels of anti-tetanus toxin antibodies until the production of the patient’s own antibodies starts.", "D": "It does not make sense to administer tetanus toxoid as it will fail to induce sufficient immunity in patients aged more than 60 years.", "E": "Immunoglobulin administration can provide constant levels of antibodies in the patient’s blood for more than 4 months."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old man is brought to the emergency department because of a 3-day history of left flank pain. The patient has had two episodes of urolithiasis during the last year. He initially had pain with urination that improved with oxycodone. Over the past day, the pain has worsened and he has additionally developed fever and chills. He has hypertension and type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for 20 years. He does not drink alcohol. His current medications include metformin and lisinopril. The patient appears ill and uncomfortable. His temperature is 39.1°C (102.3°F), pulse is 108/min, respirations are 22/min, and blood pressure is 90/62 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no murmurs, rubs, or gallops. Examination of the back shows left costovertebral angle tenderness. Physical and neurologic examinations show no other abnormalities. Laboratory studies show:\nHemoglobin 14.2 g/dL\nLeukocyte count 13,900/mm3\nHemoglobin A1c 8.2%\nSerum\nNa+ 138 mEq/L\nK+ 3.8 mEq/L\nCl-\n98 mEq/L\nCalcium 9.3 mg/dL\nGlucose 190 mg/dL\nCreatinine 2.1 mg/dL\nUrine pH 8.3\nUrine microscopy\nBacteria moderate\nRBC 6–10/hpf\nWBC 10–15/hpf\nWBC casts numerous\nUltrasound shows enlargement of the left kidney with a dilated pelvis and echogenic debris. CT scan shows a 16-mm stone at the left ureteropelvic junction, dilation of the collecting system, thickening of the wall of the renal pelvis, and signs of perirenal inflammation. Intravenous fluid resuscitation and intravenous ampicillin, gentamicin, and morphine are begun. Which of the following is the most appropriate next step in the management of this patient?\"", "answer": "Percutaneous nephrostomy", "options": {"A": "Percutaneous nephrostomy", "B": "Tamsulosin therapy", "C": "Ureteroscopy and stent placement", "D": "Shock wave lithotripsy", "E": "Intravenous pyelography"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 48-year-old homeless man is brought to the emergency department 2 hours after his right arm was burned by a fire. He is diagnosed with extensive third-degree burns of the right forearm and upper arm and is admitted to the hospital for debridement and grafting. During his stay in the hospital, he suddenly develops confusion and agitation. Neurologic examination shows horizontal nystagmus and a broad-based gait. Laboratory studies show decreased erythrocyte transketolase activity. Administration of which of the following most likely caused this patient's current condition?", "answer": "Glucose", "options": {"A": "Cobalamin", "B": "Glucose", "C": "Aspirin", "D": "Hypertonic saline", "E": "Haloperidol"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 11-year-old girl comes to the physician with her mother because of a 2-day history of passing “cola-colored“ urine. During the past week, her mother noticed episodes of facial swelling. The patient had a rash on her face about 4 weeks ago. A renal biopsy after immunofluorescence is shown. Which of the following is the most likely diagnosis?", "answer": "Poststreptococcal glomerulonephritis", "options": {"A": "Poststreptococcal glomerulonephritis", "B": "IgA nephropathy", "C": "Membranoproliferative glomerulonephritis", "D": "Diffuse proliferative glomerulonephritis", "E": "Rapidly progressive glomerulonephritis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 69-year-old woman with type 2 diabetes mellitus has an HbA1c of 3.9% and has been using basal-bolus insulin to manage her diabetes for the past 5 years. She has been maintaining a healthy diet, taking her insulin as scheduled but her records show morning hyperglycemia before eating breakfast. To determine the cause of this hyperglycemia, you ask her to set an alarm and take her blood glucose at 3 am. At 4 am her blood glucose is 49 mg/dL. Which of the following statements best describes the management of this patient’s current condition?", "answer": "She is experiencing Somogyi effect so her nighttime insulin should be decreased", "options": {"A": "She is experiencing dawn phenomenon so her nighttime insulin should be increased", "B": "She is experiencing dawn phenomenon so her nighttime insulin should be decreased", "C": "She is experiencing Somogyi effect so her nighttime insulin should be increased", "D": "She is experiencing Somogyi effect so her nighttime insulin should be decreased", "E": "Hyperosmolar hyperglycemic state; increase nighttime insulin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old man is brought to the emergency department after being attacked with a knife. Physical examination shows a 4-cm laceration in the midline of the right forearm. An MRI of the right arm shows damage to a nerve that runs between the superficial and deep flexor digitorum muscles. Loss of sensation over which of the following areas is most likely in this patient?", "answer": "Fingertip of the index finger", "options": {"A": "Palmar surface of the little finger", "B": "Lateral aspect of the forearm", "C": "Fingertip of the index finger", "D": "Medial aspect of the forearm", "E": "Dorsum of the thumb"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old nulliparous woman at 8 weeks' gestation comes to her physician accompanied by her husband for her first prenatal visit. She has no personal or family history of serious illness. Her vaccinations are up-to-date and she takes no medications. She has no history of recreational drug use and does not drink alcohol. Her vital signs are within normal limits. She is 167 cm (5 ft 6 in) tall and weighs 68 kg (150 lb); BMI is 24.3 kg/m2. She tested negative for HIV, Chlamydia trachomatis, and Neisseria gonorrhoeae 4 years ago. Which of the following tests should be done at this visit?", "answer": "ELISA for HIV, rapid plasma reagin test, and serum HBsAg", "options": {"A": "Culture for group B streptococci, hepatitis C serology, and PPD skin test", "B": "Serum TSH, CMV serology, and PCR for HSV-2", "C": "PCR for HSV-2, culture for group B streptococci, and Western blot for HIV", "D": "VDRL, Western blot for HIV, and serum HBsAg", "E": "ELISA for HIV, rapid plasma reagin test, and serum HBsAg"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old woman presents with generalized edema, hematuria, and severe right-sided flank pain. Her vital signs are normal. A 24-hour urine collection shows >10 grams of protein in her urine. Serum LDH is markedly elevated. Contrast-enhanced spiral CT scan shows thrombosis of the right renal vein. Which of the following is the most likely mechanism behind this thrombosis?", "answer": "Urinary loss of antithrombin III", "options": {"A": "Severe dehydration", "B": "Urinary loss of antithrombin III", "C": "Hepatic synthetic failure", "D": "Oral contraceptive pills", "E": "Hereditary factor VIII deficiency"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Ten days after undergoing left hip replacement, a 73-year-old hospitalized man develops a fever, dyspnea, cough productive of yellow sputum, confusion, nausea, and diarrhea. Several patients in the hospital report similar symptoms. Physical examination shows decreased breath sounds on the left side and inspiratory crackles over the left lung. An x-ray of the chest shows opacities in the lower lobe of the left lung. Treatment with ampicillin does not improve his symptoms. Subsequent evaluation of the patient's urine detects a pathogen-specific antigen, confirming the diagnosis. Which of the following sources of infection is most likely responsible for this local disease outbreak?", "answer": "Colonization of the air conditioning system", "options": {"A": "Transmission via infectious respiratory droplets", "B": "Contamination of reheated hospital food", "C": "Colonization of the air conditioning system", "D": "Entry through colonized intravenous catheters", "E": "Insufficient adherence to hand hygiene measures"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A group of scientists is studying various methods of bacterial reproduction. They find out that bacteria also exchange genetic material via these reproductive processes. They are about to study one such method known as bacterial conjugation. Which of the following occurs through bacterial conjugation?", "answer": "Two Pseudomonas aeruginosa bacteria with identical copies of a plasmid after sharing DNA through sex pili.", "options": {"A": "Two Pseudomonas aeruginosa bacteria with identical copies of a plasmid after sharing DNA through sex pili.", "B": "Helicobacter pylori producing a prophage-encoded toxin.", "C": "A strain of MRSA acquiring the gene of capsulation from another encapsulated strain via DNA extraction.", "D": "A multidrug-resistant Shigella species passing resistance factor R to a Streptococcus species.", "E": "A single E. coli bacteria with resistance to gentamicin splits into two E. coli bacteria, both of which have resistance to gentamicin."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 81-year-old man is brought in by his neighbor with altered mental status. The patient’s neighbor is unsure exactly how long he was alone, but estimates that it was at least 3 days. The neighbor says that the patient usually has his daughter at home to look after him but she had to go into the hospital recently. The patient is unable to provide any useful history. Past medical history is significant for long-standing hypercholesterolemia and hypertension, managed medically with rosuvastatin and hydrochlorothiazide, respectively. His vital signs include: blood pressure, 140/95 mm Hg; pulse, 106/min; temperature, 37.2°C (98.9°F); and respiratory rate, 19/min. On physical examination, the patient is confused and unable to respond to commands. His mucus membranes are dry and he has tenting of the skin. The remainder of the exam is unremarkable. Laboratory findings are significant for the following:\nSodium 141 mEq/L\nPotassium 4.1 mEq/L\nChloride 111 mEq/L\nBicarbonate 21 mEq/L\nBUN 40 mg/dL\nCreatinine 1.4 mg/dL\nGlucose (fasting) 80 mg/dL\n  Magnesium 1.9 mg/dL\nCalcium 9.3 mg/dL\nPhosphorous 3.6 mg/dL\n24-hour urine collection\nUrine Sodium 169 mEq/24 hr (ref: 100–260 mEq/24 hr)\nUrine Creatinine 79.5 g/24 hr (ref: 1.0–1.6 g/24 hr)\nWhich of the following is the most likely cause of this patient’s acute renal failure?", "answer": "Dehydration", "options": {"A": "Acute tubular necrosis", "B": "Dehydration", "C": "Sepsis", "D": "NSAID use", "E": "UTI due to obstructive nephrolithiasis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old man is brought to the emergency department by a friend because of a 5-day history of fever and cough productive of purulent sputum. One week ago, he was woken up by an episode of heavy coughing while lying on his back. He drinks large amounts of alcohol daily and has spent most of his time in bed since his wife passed away 2 months ago. His temperature is 38°C (100.4°F), pulse is 96/min, respirations are 24/min, and blood pressure is 110/84 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 87%. Physical examination shows poor dentition and swollen gums. A CT scan of the chest is most likely to show a pulmonary infiltrate in which of the following locations?", "answer": "Superior segment of the right lower lobe", "options": {"A": "Posterior basal segment of the right lower lobe", "B": "Apicoposterior segment of the left upper lobe", "C": "Superior segment of the right lower lobe", "D": "Posterior basal segment of the left lower lobe", "E": "Posterior segment of the right upper lobe"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old man is brought to the emergency department because his neck was fixed in lateral flexion. For the past week, the patient has been complaining of low-grade fever, head pain, and neck pain. His partner has also noticed him behaving erratically. His family and personal medical history are not relevant. Upon admission, he is found with a body temperature of 38.6°C (101.5°F), and physical examination is unremarkable except for neck pain and fixed lateral flexion of the neck. He is confused, but there are no motor or sensory deficits. Deep tendon reflexes are accentuated. Magnetic resonance imaging of the brain shows leptomeningeal and gyral enhancement. Which of the following explains this patient’s condition?", "answer": "Viral infection", "options": {"A": "Genetic mutation", "B": "Exposure to D2-antagonists", "C": "Trochlear nerve palsy", "D": "Viral infection", "E": "Acid-fast resistant bacilli infection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old software professional consults a physician to discuss his concerns about small-vessel vasculitis as his mother and sister both have autoimmune small-vessel vasculitides. He has read about vasculitides and recently he came across an article which stated that an analgesic that he often uses for relief from a headache can cause small-vessel vasculitis. Due to his positive family history, he is especially concerned about his risk of developing small-vessel vasculitis. Which of the following clinical presentations is most likely to occur in this man?", "answer": "Palpable purpura", "options": {"A": "Absence of pulses in the upper extremity", "B": "Infarction of an internal organ", "C": "Stroke", "D": "Aneurysm of an artery", "E": "Palpable purpura"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 22-year-old man with no significant medical history presents with a two day history of bilateral eye redness, irritation, and watery mucous discharge as seen in the photograph provided. He has crusting of his eyes in the mornings without adhesion of his eyelids. He does not wear contact lenses and has had a sore throat the last three days. On physical exam, a left preauricular lymph node is enlarged and tender. An ophthalmologic exam reveals no additional abnormalities. Which of the following is the most appropriate treatment for this patient?", "answer": "Warm compresses", "options": {"A": "Topical erythromycin ointment", "B": "Oral azithromycin", "C": "Topical moxifloxacin", "D": "Warm compresses", "E": "Topical glucocorticoids"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old man with an unknown previous medical history is found on the floor at home by his daughter. During the initial assessment, the patient has right-sided arm weakness and incomprehensible speech. The patient is admitted to the hospital where he is diagnosed with an ischemic stroke where his magnetic resonance image (MRI) scan showed diffusion restriction in the right middle cerebral artery (MCA) territory. Further evaluation reveals the patient had been on the floor for about 2 days before he was found by his daughter. At presentation to the hospital, the blood pressure is 161/88 mm Hg and the heart rate is 104/min and regular. His laboratory values at the time of admission are shown:\nBUN 40 mg/dL\nCreatinine 1.9 mg/dL\nPotassium 5.3 mEq/dL\nSodium 155 mEq/dL\nChloride 100 mEq/dL\nHCO3 24 mmol/L\nHemoglobin 13.8 g/dL\nHematocrit 40%\nLeukocytes 11,000/mL\nPlatelets 300,000/µL\nSerum creatine kinase 40,000 U/L\nWhich of the following is most indicated in this patient?", "answer": "Forced diuresis with intravenous (IV) fluids", "options": {"A": "Forced diuresis with intravenous (IV) fluids", "B": "Stress echocardiography", "C": "Intravenous n-acetyl-cysteine", "D": "Transfusion of fresh frozen plasma (FFP)", "E": "Rhythm control with metoprolol"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 16-year-old girl is brought to the emergency department by her parents because of fever, vomiting, rash, and worsening confusion since this morning. On questioning, her mother reports that her last menstrual period was 1 week ago and that she recently started using tampons. She appears lethargic and is only oriented to person. Her temperature is 40.4°C (104.7°F), pulse 174/minute, and blood pressure is 62/44 mm Hg. Examination shows oropharyngeal hyperemia and diffuse macular erythroderma. Which of the following is the most likely cause of this patient's condition?", "answer": "Polyclonal T cell activation", "options": {"A": "Erythrogenic toxin production", "B": "Lipooligosaccharide expression", "C": "Unregulated B cell proliferation", "D": "Generalized mast cell degranulation", "E": "Polyclonal T cell activation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old man is brought to the emergency department after a motor vehicle accident. He complains of tingling of his legs, and he is unable to move them. His temperature is 36.5°C (97.7°F), the blood pressure is 110/75 mm Hg, and the pulse is 88/min. On physical examination, pinprick sensation is absent below the umbilicus and there is no rectal tone. Muscle strength in the lower extremities is 1/5 bilaterally. He has 5/5 strength in his bilateral upper extremities. Plain films and computerized tomography (CT) show the displacement of the lumbar vertebrae. Which of the following is the best next step in the management of this patient?", "answer": "Intravenous methylprednisolone", "options": {"A": "Positron emission tomography (PET) scan of the spine", "B": "Intravenous methylprednisolone", "C": "CT myelography", "D": "Radiation therapy", "E": "Intravenous antibiotics"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old Indian female is hospitalized with exertional dyspnea and lower extremity edema. The patient immigrated to the United States at age 15 and does not use tobacco, alcohol, or drugs. A mid-diastolic murmur is present and heard best at the apex. Which of the following symptoms would be most consistent with the rest of the patient’s presentation?", "answer": "Hoarseness", "options": {"A": "Hoarseness", "B": "Pulsus parodoxus", "C": "Asymmetric ventricular hypertrophy", "D": "Increased intracranial pressure", "E": "Hirsutism"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 14-year-old Caucasian girl presents to the pediatrician for poor balance. She reports a 7-month history of frequent falls that has progressively worsened. She has fallen 3 times in the past week and feels like she cannot walk normally. She was born full-term and spent 2 days in the neonatal intensive care unit for respiratory distress. She has had an otherwise normal childhood. Her family history is notable for multiple cardiac deaths before the age of 60. Her mother had a posterior spinal fusion for kyphoscoliosis as an adolescent. On exam, the patient has 4/5 strength in her bilateral upper and lower extremities. She walks with a staggering gait. Pes cavus is appreciated bilaterally. Skin examination is normal. This patient has a condition that is caused by a trinucleotide repeat of which of the following nucleotides?", "answer": "GAA", "options": {"A": "CAG", "B": "CGG", "C": "CTG", "D": "GAA", "E": "GAC"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old farmer presents to his primary care physician for the first time appointment. The patient has never seen a doctor and states that he is in good health. He has worked as a farmer for the past 30 years and has no complaints. His temperature is 98.9°F (37.2°C), blood pressure is 197/118 mmHg, pulse is 90/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam is notable for an obese man in no current distress. Laboratory values are seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 101 mEq/L\nK+: 5.2 mEq/L\nHCO3-: 25 mEq/L\nBUN: 34 mg/dL\nGlucose: 179 mg/dL\nCreatinine: 2.1 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the best management of this patient's blood pressure?", "answer": "Lisinopril", "options": {"A": "Carvedilol", "B": "Hydrochlorothiazide", "C": "Lisinopril", "D": "Metoprolol", "E": "Nicardipine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old woman presents to the office complaining of bloating and consistent fatigue. Past medical notes on her record show that she has seen several doctors at the clinic in the past year for the same concerns. During the discussion, she admits that coming to the doctor intensifies her anxiety and she does not enjoy it. However, she came because she fears that she has colon cancer and says, “There’s gotta be something wrong with me, I can feel it.” Past medical history is significant for obsessive-compulsive disorder (OCD). She sees a therapist a few times a month. Her grandfather died of colon cancer at 75. Today, her blood pressure is 120/80 mm Hg, heart rate is 90/min, respiratory rate is 18/min, and temperature is 37.0°C (98.6°F). Physical examination reveals a well-nourished, well-developed woman who appears anxious and tired. Her heart has a regular rhythm and her lungs are clear to auscultation bilaterally. Her abdomen is soft, non-tender, and non-distended. No masses are palpated, and a digital rectal examination is unremarkable. Laboratory results are as follows:\nSerum chemistry \nHemoglobin 13 g/dL \nHematocrit\n38%\nMCV 90 fl\nTSH\n4.1 μU/mL\nFecal occult blood test  negative\nWhich of the following is the most likely diagnosis?", "answer": "Illness anxiety disorder", "options": {"A": "Malingering", "B": "Somatic symptoms disorder", "C": "Body dysmorphic disorder", "D": "Illness anxiety disorder", "E": "Generalized anxiety disorder"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man presents to his primary care physician for lower extremity pain and unsteadiness. He describes the pain as severe and stabbing and affecting his lower extremities. These episodes of pain last for minutes at a time. He also reports knocking into furniture regularly. Medical history is significant for streptococcal pharyngitis, where he had a severe allergic reaction to appropriate treatment. He is currently sexually active with men and does not use condoms. On physical exam, his pupils are miotic in normal and low light. The pupils do not constrict further when exposed to the penlight and there is no direct or consensual pupillary dilation when the penlight is removed. The pupils constrict further when exposed to a near object. He has decreased vibration and proprioception sense in his lower extremities, absent lower extremity deep tendon reflexes, and a positive Romberg test. Which of the following is the best next step in management?", "answer": "Intravenous penicillin", "options": {"A": "Intramuscular penicillin", "B": "Intramuscular ceftriaxone", "C": "Intravenous doxycycline", "D": "Intravenous penicillin", "E": "Oral doxycycline"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old male wrestler presents to his primary care physician for knee pain. He was in a wrestling match yesterday when he was abruptly taken down. Since then, he has had pain in his left knee. The patient states that at times it feels as if his knee locks as he moves it. The patient has a past medical history of anabolic steroid abuse; however, he claims to no longer be using them. His current medications include NSAIDs as needed for minor injuries from participating in sports. On physical exam, you note medial joint tenderness of the patient’s left knee, as well as some erythema and bruising. The patient has an antalgic gait as you observe him walking. Passive range of motion reveals a subtle clicking of the joint. There is absent anterior displacement of the tibia relative to the femur on an anterior drawer test. The rest of the physical exam, including examination of the contralateral knee is within normal limits. Which of the following structures is most likely damaged in this patient?", "answer": "Medial meniscus", "options": {"A": "Medial meniscus", "B": "Lateral meniscus", "C": "Medial collateral ligament", "D": "Lateral collateral ligament", "E": "Anterior cruciate ligament"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 71-year-old woman comes to the physician because of progressive shortness of breath and swollen legs for 4 weeks. She has tried sleeping in a raised position using 2 pillows but still wakes up occasionally from a choking sensation. She returned from a safari tour in Tanzania 3 months ago. She has type 2 diabetes mellitus, arterial hypertension, and gastroesophageal reflux disease. Her sister has polymyalgia rheumatica. Her current medications include insulin, enalapril, and omeprazole. She has smoked one half-pack of cigarettes daily for 45 years. Her temperature is 37°C (98.6°F), pulse is 112/min, respirations are 22/min, and blood pressure is 119/76 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 90%. Examination shows pitting edema below the knees and jugular venous distention. Crackles are heard at both lung bases. A photograph of her tongue is shown. Her hemoglobin concentration is 10.0 g/dL, leukocyte count is 6,100/mm3, and erythrocyte sedimentation rate is 62 mm/h. ECG shows sinus rhythm and low-voltage QRS complexes. Echocardiography shows symmetrical left ventricular hypertrophy, reduced diastolic filling, and an ejection fraction of 55%. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Multiple myeloma", "options": {"A": "Endocardial fibroelastosis", "B": "Systemic sclerosis", "C": "Multiple myeloma", "D": "Tuberculosis", "E": "Rheumatoid arthritis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 6-year-old boy is brought to the pediatrician by his mother for diarrhea and a skin rash. His mother reports that he had a cough, sore throat, and runny nose 1 week ago. Although his upper respiratory symptoms improved after two days, he started having multiple watery bowel movements 3 days ago. He also developed a red pruritic rash on his arms, legs, and neck at that time. His mother also reports that he has had similar symptoms in the past that have occurred after the boy gets sick. His temperature is 98.8°F (37.1°C), blood pressure is 109/68 mmHg, pulse is 92/min, and respirations are 19/min. The child is alert and oriented to person but not place or time. He is unable to count to 10 even though his mother says he can normally count to 100 easily. He walks with a wide-based gait. An erythematous patchy rash is noted on his upper and lower extremities bilaterally. A complete blood count and basic metabolic panel are within normal limits. A urinalysis reveals elevated levels of neutral amino acids. Which of the following is the most appropriate acute treatment for this patient?", "answer": "Nicotinic acid", "options": {"A": "Nicotinic acid", "B": "Phenylbutyrate", "C": "Pyridoxine", "D": "Tryptophan", "E": "Tyrosine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old man comes to the physician because of a 5-month history of progressive fatigue and exertional dyspnea. Cardiac examination shows a loud S2 in the 2nd left intercostal space. Right heart catheterization shows a pulmonary artery pressure of 32 mm Hg. Treatment with bosentan is initiated. The beneficial effect of this drug is due to binding to which of the following?", "answer": "Endothelin receptors", "options": {"A": "L-type voltage-gated calcium channels", "B": "Phosphodiesterase-5", "C": "Prostacyclin receptor", "D": "Adenosine receptors", "E": "Endothelin receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2-week-old newborn girl is brought to the physician for a follow-up examination after the initial newborn examination showed asymmetry of the legs. She was born at term to a 26-year-old woman, gravida 3, para 2. Pregnancy was complicated by a breech presentation and treated with an emergency lower-segment transverse cesarean section. The newborn's head circumference is 35 cm (13.7 in). She is at the 60th percentile for length and 75th percentile for weight. Cardiac examination shows no abnormalities. The spine and overlying skin do not indicate significant abnormalities. Abduction of the right hip after cupping the pelvis and flexing the right hip and knee causes a palpable clunk. The feet exhibit no deformities. Ultrasonography of the hip revealed a 50° angle between the lines along the bone acetabulum and the ilium. Which of the following is the most appropriate next step in management?", "answer": "Treat using a harness", "options": {"A": "Immobilize the hips with a spica cast", "B": "Obtain an MRI of the right hip", "C": "Obtain an X-ray of the right hip", "D": "Reassure the mother and schedule follow-up appointment in 4 weeks", "E": "Treat using a harness"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old woman comes to the physician because of a progressive swelling in her mouth that she first noticed 5 years ago. Initially, the swelling was asymptomatic but has now caused some difficulty while chewing food for the past month. She has no pain. She has not undergone any dental procedures in the past 5 years. She has bronchial asthma. Her only medication is an albuterol inhaler. She appears healthy. Her temperature is 37°C (98.6°F), pulse is 70/min, and blood pressure is 110/70 mm Hg. Examination shows a 1.5-cm smooth, unilobular, bony hard, nontender mass in the midline of the hard palate. There is no cervical or submandibular lymphadenopathy. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Torus palatinus\n\"", "options": {"A": "Palatal pleomorphic adenoma", "B": "Necrotizing sialometaplasia", "C": "Nasopalatine duct cyst", "D": "Palatal abscess", "E": "Torus palatinus\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 54-year-old man presents to the emergency department after vomiting blood an hour ago. He says this happens to him occasionally but denies feeling pain in these episodes. The man is disheveled and has slurred speech as he describes his symptoms. He is reluctant to give further history and wants immediate treatment of his condition. Upon examination, the patient has evidence of tortuous veins visible on his abdomen plus a yellow tinge to his sclerae. He suddenly begins vomiting copious amounts of blood and soon becomes unresponsive. His blood pressure drops to 70/40 mm Hg. He is given 3 units of whole blood but passes away shortly after the incident. Which of the following was the most likely cause of his vomiting of blood?", "answer": "Increased pressure in the distal esophageal vein due to increased pressure in the left gastric vein", "options": {"A": "Increased pressure in the distal esophageal vein due to increased pressure in the left gastric vein", "B": "Lacerations of the mucosa at the gastroesophageal junction", "C": "Perforation of the gastric mucosa", "D": "Decreased GABA activity due to downregulation of receptors", "E": "Inflammation of the portal tract due to a chronic viral illness"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old man is brought to the emergency room because of fever and increasing confusion for the past 2 days. He has paranoid schizophrenia treated with chlorpromazine. He appears diaphoretic. His temperature is 40°C (104°F), pulse is 130/min, respirations are 29/min, and blood pressure is 155/100 mm Hg. Neurologic examination shows psychomotor agitation and incoherent speech. There is generalized muscle rigidity. His deep tendon reflexes are decreased bilaterally. Serum laboratory analysis shows a leukocyte count of 11,300/mm3 and serum creatine kinase concentration of 833 U/L. The most appropriate drug for this patient acts by inhibiting which of the following?", "answer": "Ryanodine receptor on the sarcoplasmic reticulum", "options": {"A": "Cholinesterase", "B": "Postsynaptic dopamine D2 receptors and serotonin 2A receptors", "C": "Ryanodine receptor on the sarcoplasmic reticulum", "D": "Histamine H1 receptor and serotonin 2 receptors", "E": "Beta adrenergic receptors"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-month-old infant is brought to the emergency by his parents after a seizure. The parents report no history of trauma, fever, or a family history of seizures. However, they both say that the patient fell while he was running. Neurologic examination was normal. A head CT scan was ordered and is shown in figure A. Which of the following is most likely found in this patient?", "answer": "Retinal hemorrhages", "options": {"A": "Slipped capital femoral epiphysis", "B": "Retinal hemorrhages", "C": "Microcephaly", "D": "Rupture of middle meningeal artery", "E": "Intact bridging veins"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 80-year-old woman presents to her cardiologist for a scheduled appointment. She was shown to have moderate atrial dilation on echocardiography 3 years ago and was started on oral medications. The patient insists that she does not want aggressive treatment because she wants her remaining years to be peaceful. She has not been compliant with her medications and declines further investigations. Her heart rate today is 124/min and irregular. Which of the following organs is least likely to be affected by complications of her condition if she declines further management?", "answer": "Liver", "options": {"A": "Brain", "B": "Eyes", "C": "Kidneys", "D": "Liver", "E": "Spleen"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old girl is brought in by her parents to her pediatrician for concerns about their child’s behavior. Since the parents started taking their child to daycare, they have become concerned that their daughter has not been behaving like other children her age. Most notably, she seldom responds when her name is called at home or at daycare. Additionally, she has been getting in trouble with the day care staff for not following directions but instead demanding to play with the train set at all times. She has been asked numerous times to share the toys, but the patient does not play with the other children. The parents state that the patient was born vaginally following a normal pregnancy, and the patient had been meeting developmental milestones all along. While she does not speak much, she is able to construct sentences up to 4-5 words. On exam, the patient’s temperature is 98.2°F (36.8°C), blood pressure is 106/60 mmHg, pulse is 76/min, and respirations are 14/min. The patient does not cooperate with gross or fine motor testing, but she appears to have no trouble running around the room and draws very detailed trains with crayons. While drawing and standing, she frequently makes flapping motions with her hands. The patient has ample vocabulary, but speaks in a singsong voice mostly to herself and does not engage during the exam. Which of the following is the most likely diagnosis?", "answer": "Autism spectrum disorder", "options": {"A": "Attention-deficit hyperactivity disorder", "B": "Autism spectrum disorder", "C": "Normal development", "D": "Rett syndrome", "E": "Tourette syndrome"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old man comes to the physician because of multiple, dry, scaly lesions on his elbows. The lesions appeared 4 months ago and have progressively increased in size. They are itchy and bleed when he scratches them. There is no associated pain or discharge. He was diagnosed with HIV infection 6 years ago. He has smoked a pack of cigarettes daily for the past 10 years. Current medications include raltegravir, lamivudine, abacavir, and cotrimoxazole. An image of the lesions is shown. His CD4+ T-lymphocyte count is 470/mm3 (normal ≥ 500). Which of the following is the most likely cause of this patient's skin findings?", "answer": "Increased keratinocyte proliferation", "options": {"A": "HPV-2 infection", "B": "Malassezia furfur infection", "C": "Neoplastic T-cell Infiltration", "D": "Increased keratinocyte proliferation", "E": "Autoimmune melanocyte destruction\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old African-American woman presents with dyspnea, cough, and non-radiating chest pain. Her chest pain is relieved by leaning forward and worsens upon leaning backwards. A scratchy rub is heard best with the patient leaning forward. Physical examination did not elucidate evidence of a positive Kussmaul's sign, pulsus paradoxus, or pericardial knock. The patient most likely is suffering from which of the following?", "answer": "Acute pericarditis", "options": {"A": "Cardiac tamponade", "B": "Constrictive pericarditis", "C": "Acute pericarditis", "D": "Libman-Sacks endocarditis", "E": "Acute myocardial infarction"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Shortly after the removal of a subclavian venous catheter by a surgical resident in an academic medical center, a 50-year-old man develops tachycardia, respiratory distress, and hypotension. Despite appropriate lifesaving treatment, the patient dies. Examination of the lungs during autopsy shows air in the main pulmonary artery. A root cause analysis is performed to prevent similar events occurring in the future. Which of the following actions is a primary approach for this type of error analysis?", "answer": "Conduct interviews with all staff members involved in the patient's care", "options": {"A": "Schedule a required lecture on central venous catheter removal for all residents", "B": "Examine the central line placement curriculum used for all surgical residents", "C": "Research other cases of catheter-associated venous air embolisms that have occurred nationally", "D": "Conduct interviews with all staff members involved in the patient's care", "E": "Review all possible causes of venous air embolism"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 63-year-old woman comes to the physician because of a skin lesion on her neck for 7 months. It is neither pruritic nor painful. She has tried using over-the-counter topical medications, but none have helped. She has hypertension, hypothyroidism, and gastroesophageal reflux disease. Current medications include amlodipine, hydrochlorothiazide, levothyroxine, and pantoprazole. She is a farmer and lives with her two children. Her temperature is 37.7°C (98.8°F), pulse is 80/min, respirations are 15/min, and blood pressure is 128/84 mm Hg. Examination shows a 5-mm (0.2-in) nontender, indurated, nodular lesion with rolled-out edges on the anterolateral aspect of the neck. There is a central area of ulceration. There is no cervical lymphadenopathy. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. In addition to dermoscopy, which of the following is the most appropriate next step in management?", "answer": "Perform an excisional biopsy of the entire lesion", "options": {"A": "Perform a punch biopsy of the center of the lesion", "B": "Perform an excisional biopsy of the entire lesion", "C": "Schedule external beam radiotherapy sessions", "D": "Perform cryotherapy on the lesion", "E": "Perform a wedge biopsy of the lesion and surrounding tissue"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man comes to the physician for a follow-up examination after being diagnosed with hypertension 6 months ago. He has cut salt out of his diet and started exercising regularly, but home blood pressure measurements continue to be elevated. His blood pressure is 160/85 mm Hg. An antihypertensive medication is prescribed that decreases blood pressure by decreasing the transmembrane calcium current across vascular smooth muscle cells. Side effects include peripheral edema and flushing. Which of the following best describes why this drug does not affect skeletal muscle contraction?", "answer": "Skeletal muscle contraction occurs independently of extracellular calcium influx", "options": {"A": "Skeletal muscle lacks voltage-gated L-type calcium channels", "B": "Skeletal muscle contraction occurs independently of extracellular calcium influx", "C": "Skeletal muscle ryanodine receptor activation occurs independently of membrane depolarization", "D": "Skeletal muscle preferentially expresses N-type and P-type calcium channels", "E": "Skeletal muscle calcium channels do not undergo conformational change when bound to this drug"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 10-year-old boy presents with sudden shortness of breath. The patient’s mother says he was playing in the school garden 2 hours ago and suddenly started to complain of abdominal pain and vomited a few times. An hour later, he slowly developed a rash that involved his chest, arms, and legs, and his breathing became faster, with audible wheezing. He has no significant past medical history. His temperature is 37.0°C (98.6°F), blood pressure is 100/60 mm Hg, pulse is 130/min, and respirations are 25/min. On physical examination, there is a rash on his right arm (shown in the image, below). Which of the following cells will mainly be found in this patient if a histological sample is taken from the site of the skin lesion 4 hours from now?", "answer": "Neutrophils", "options": {"A": "Mast cells", "B": "Basophils", "C": "Fibroblasts", "D": "Plasma cells", "E": "Neutrophils"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old man comes to the emergency department because of a 2-day history of sharp chest pain and a nonproductive cough. The pain worsens with deep inspiration and improves when he leans forward. Three weeks ago, the patient was diagnosed with an ST-elevation myocardial infarction and underwent stent implantation of the right coronary artery. His temperature is 38.4°C (101.1°F) and blood pressure is 132/85 mm Hg. Cardiac auscultation shows a high-pitched scratching sound during expiration. An x-ray of the chest shows enlargement of the cardiac silhouette and a left-sided pleural effusion. Which of the following is the most likely underlying cause of this patient's current condition?", "answer": "Immune response to cardiac antigens", "options": {"A": "Outpouching of ventricular wall", "B": "Occlusion of coronary artery stent", "C": "Embolism to left pulmonary artery", "D": "Immune response to cardiac antigens", "E": "Rupture of interventricular septum"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Which of the following correctly pairs a neurotransmitter with its location of synthesis?", "answer": "Serotonin -- Raphe nucleus", "options": {"A": "Norepinephrine -- Caudate nucleus", "B": "GABA -- Ventral tegmentum", "C": "Dopamine -- Locus ceruleus", "D": "Serotonin -- Raphe nucleus", "E": "Acetylcholine -- Nucleus accumbens"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old man presents to the emergency department with abdominal pain. The patient states that he has had right lower quadrant abdominal pain for \"a while now\". The pain comes and goes, and today it is particularly painful. The patient is a college student studying philosophy. He drinks alcohol occasionally and is currently sexually active. He states that sometimes he feels anxious about school. The patient's father died of colon cancer at the age of 55, and his mother died of breast cancer when she was 57. The patient has a past medical history of anxiety and depression which is not currently treated. Review of systems is positive for bloody diarrhea. His temperature is 99.5°F (37.5°C), blood pressure is 100/58 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. Cardiopulmonary exam is within normal limits. Abdominal exam reveals diffuse tenderness. A fecal occult blood test is positive. Which of the following is the most likely diagnosis?", "answer": "Inflammatory bowel syndrome", "options": {"A": "Appendicitis", "B": "Colon cancer", "C": "Infectious colitis", "D": "Inflammatory bowel syndrome", "E": "Irritable bowel syndrome"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 12-year-old girl is brought to the physician because of fatigue, dyspnea, and mild chest pain on exertion for 1 week. She does not have a fever or a rash. She had an upper respiratory infection 3 weeks ago. She returned from summer camp in Colorado 3 days ago. She says they went hiking and camping as part of their activities. Her temperature is 36.9°C (98.4°F), heart rate is 96/min, and blood pressure is 106/74 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Physical examination reveals jugular venous distention and 1+ pitting edema on both ankles. A few scattered inspiratory crackles are heard in the thorax and an S3 is heard at the apex. Abdominal examination is unremarkable. Her hemoglobin concentration is 11.6 g/dL, leukocyte count is 8900/mm3, and ESR is 10 mm/hr. An x-ray of the chest shows mild cardiac enlargement. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Coxsackie virus infection", "options": {"A": "Acute rheumatic fever", "B": "Giant cell myocarditis", "C": "Borrelia burgdorferi infection", "D": "Coxsackie virus infection", "E": "Rhinovirus infection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2-year-old boy is brought to a pediatrician for recurrent respiratory infections. The parents explain that their child has gotten sick every month since 2 months of age. The boy had multiple upper respiratory infections and has been treated for pneumonia twice. He coughs frequently, and a trial of salbutamol has not helped much. The parents also mention that the child has bulky, irregular stools. The boy was started late on his vaccinations as his parents were in Asia on missionary work when he was born, but his vaccinations are now up to date. The patient's brother and sister are both healthy and have no medical concerns. The boy's delivery was unremarkable. A sweat chloride test is positive. Genetic testing shows the absence of the typical deletion in the implicated gene, but the gene length appears to be shortened by one base pair. Which mutation could account for this finding?", "answer": "Frameshift", "options": {"A": "Frameshift", "B": "Insertion", "C": "Missense", "D": "Nonsense", "E": "Silent"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old man comes to the physician for evaluation of a headache he has had for the last 6 months. The patient reports that nothing helps to relieve the headache and that it is more severe in the morning. Throughout the last 2 months, he has been unable to maintain an erection and states that his sexual desire is low. There is no personal or family history of serious illness. His temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 150/90 mm Hg. Examination shows an enlarged nose, forehead, and jaw and widened hands, fingers, and feet. His hands are sweaty. His serum glucose concentration is 260 mg/dL. Which of the following is the most appropriate next step in diagnosis?", "answer": "Serum IGF-1 measurement", "options": {"A": "Serum IGF-1 measurement", "B": "MRI of the brain", "C": "Oral glucose tolerance test", "D": "Basal prolactin measurement", "E": "24-hour urine cortisol measurement\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 68-year-old male presents with several years of progressively worsening pain in his buttocks. Pain is characterized as dull, worse with exertion especially when ascending the stairs. He has a history of diabetes mellitus type II, obesity, coronary artery disease with prior myocardial infarction, and a 44 pack-year smoking history. Current medications include aspirin, atorvastatin, metoprolol, lisinopril, insulin, metformin, and varenicline. Upon further questioning, the patient's wife states that her husband has also recently developed impotence. His temperature is 99.5°F (37.5°C), pulse is 90/min, blood pressure is 150/90 mmHg, respirations are 12/min, and oxygen saturation is 96% on room air. Which of the following is the best initial step in management?", "answer": "Ankle-brachial index", "options": {"A": "Cilostazol", "B": "Pentoxifylline", "C": "Guided exercise therapy", "D": "Ankle-brachial index", "E": "Angiography"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old man presents to the emergency department following a motor vehicle accident. Having been found as a restrained driver, he did not suffer from any chest injuries; nevertheless, his legs were pinned in position by the front of the highly damaged vehicle. After a prolonged extrication, the man sustained multiple fractures on his left femur and tibia. That same night, he underwent surgery to address his left leg fractures. In the next morning, the man suddenly developed severe dyspnea. Upon examination, he is noted to have a diffuse petechial rash. His vital signs are the following: blood pressure is 111/67 mm Hg, pulse rate is 107/min, respiratory rate is 27/min, oxygen saturation level is 82%, and his body temperature is normal. What is the most likely mechanism of his respiratory distress?", "answer": "Fat embolism", "options": {"A": "Pulmonary edema", "B": "Cardiac tamponade", "C": "Bacterial pneumonia", "D": "Spontaneous pneumothorax", "E": "Fat embolism"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old is brought to the pediatrician by by his mother. She is concerned that he appears fatigued all the time. She also mentions that he struggles to get out of his seat after eating his meals and when he waddles when he walks now. The child was born at 39 weeks via spontaneous vaginal delivery. He is up to date on all his vaccines and meeting all developmental goals. A maternal uncle with similar symptoms that started in early childhood. He has a heart rate of 90/min, respiratory rate of 22/min, blood pressure of 110/65 mm Hg, and temperature of 37.0°C (98.6°F). The child appears lethargic. He was much more active during his previous well-child visit. Upon examination, the child has thick calves and uses his hands to support himself as he stands up from a sitting position. His reflexes are decreased bilaterally. Lab studies show elevated creatinine phosphokinase (CPK) and lactate dehydrogenase (LDH). Which of the following is the most likely cause of this patient’s condition?", "answer": "Nonsense mutation in DMD gene", "options": {"A": "Missense mutation in β-thalassemia gene", "B": "Missense mutation in DMD gene", "C": "Nonsense mutation in DMD gene", "D": "Nonsense mutation in DMPK gene", "E": "Mutation in WT gene"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-month-old boy is brought to the physician by his parents because of difficulty breathing for the past hour. The parents report noisy breathing and bluish discoloration of their son's lips. During the past two months, the patient has had several upper respiratory tract infections and poor weight gain. Pregnancy and delivery were uncomplicated. His immunizations are up-to-date. He is at the 20th percentile for length and 5th percentile for weight. His temperature is 38°C (100.4°F), pulse is 160/min, respirations are 40/min, and blood pressure is 80/55 mm Hg. Crackles are heard over both lung fields. An x-ray of the chest shows bilateral interstitial infiltrates. Intubation is performed and methylprednisolone is administered. Methenamine silver staining of bronchial lavage fluid shows aggregates of 2 to 8 cysts with central spores. Serum IgA titers are decreased. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Defective CD40 ligand", "options": {"A": "Defective WAS gene", "B": "Defective CD40 ligand", "C": "Impaired lysosomal trafficking regulator gene", "D": "Tyrosine kinase gene mutation", "E": "Impaired NADPH oxidase"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old man presents to his primary care physician for fatigue. He is accompanied by his granddaughter who is worried that the patient is depressed. She states that over the past 2 months he has lost 15 lbs. He has not come to some family events because he complains of being “too tired.” The patient states that he tries to keep up with things he likes to do like biking and bowling with his friends but just tires too easily. He does not feel like he has trouble sleeping. He does agree that he has lost weight due to a decreased appetite. The patient has coronary artery disease and osteoarthritis. He has not been to a doctor in “years” and takes no medications, except acetaminophen as needed. Physical examination is notable for hepatomegaly. Routine labs are obtained, as shown below:\n\nLeukocyte count: 11,000/mm^3\nHemoglobin: 9 g/dL\nPlatelet count: 300,000/mm^3\nMean corpuscular volume (MCV): 75 µm^3\nSerum iron: 35 mcg/dL\n\nAn abdominal ultrasound reveals multiple, hypoechoic liver lesions. Computed tomography of the abdomen confirms multiple, centrally-located, hypoattenuated lesions. Which of the following is the next best step in management?", "answer": "Colonoscopy", "options": {"A": "Citalopram", "B": "Colonoscopy", "C": "Fine-needle aspiration", "D": "Fluorouracil, leucovorin, and oxaliplatin", "E": "Surgical resection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Eighteen hours after undergoing surgery for a splenic rupture and liver laceration following a high-speed motor vehicle collision, a 23-year-old man's pulse is 140/min, blood pressure is 80/50 mm Hg, and central venous pressure is 19 cm H2O. He was transfused with 6 units of packed red blood cells during surgery. Examination shows jugular venous distention. There is a midline surgical incision with no erythema or discharge. The abdomen is tense and distended. The total urine output over the past 6 hours is 90 mL. Serum studies show:\nUrea nitrogen 80 mg/dL\nCreatinine 3.0 mg/dL\nHCO3- 29 mEq/L\nWhich of the following is the most appropriate next step in management?\"", "answer": "Reopen abdomen and cover with plastic", "options": {"A": "Administration of fresh frozen plasma", "B": "Reopen abdomen and cover with plastic", "C": "Administration of intravenous antibiotics", "D": "Angiographic embolization", "E": "Hemicolonic resection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old man presents to his family physician admitting to using heroin. He says he started using about 6-months ago when his back pain medication ran out. At first, he says he would borrow his wife’s Percocet but, eventually, that ran out and he had to find a different source. Since then, he has been having more and more issues related to his heroin use, and it has started to affect his work and home life. He is concerned that, if he continues like this, he might end up in real trouble. He denies sharing needles and is sincerely interested in quitting. He recalls trying to quit last month but recounts how horrible the withdrawal symptoms were. Because of this and the strong cravings, he relapsed shortly after his initial attempt. Methadone maintenance therapy is prescribed. Which of the following would most likely be the most important benefit of this new treatment plan in this patient?", "answer": "Improved interpersonal relationships", "options": {"A": "Improved interpersonal relationships", "B": "Euphoria without the side effects", "C": "Decreased incidence of hepatitis A", "D": "Depot dosing allowing for better compliance", "E": "Decreases methadone dependence"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 53-year-old man presents to an urgent care center with severe fever that began during the day along with muscle and joint pains. He states that he felt fine the day before but then developed a fever to 103°F (39.4°C) and had to leave work after which he developed a headache and body pains. The patient states that he was recently in South Asia for a business trip and was otherwise feeling well since returning 2 weeks ago. On exam, the patient’s temperature is 103.3°F (39.6°C), blood pressure is 110/84 mmHg, pulse is 94/min, and respirations are 14/min. On physical exam, the patient appears flushed and has a rash that blanches when touched. On laboratory workup, the pathogen was identified as an enveloped virus with an icosahedral capsid and had positive-sense, single-stranded linear RNA. Which of the following is the most likely cause of this patient's presentation?", "answer": "Dengue virus", "options": {"A": "Coronavirus", "B": "Dengue virus", "C": "Marburg virus", "D": "Norovirus", "E": "Saint Louis encephalitis virus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 64-hour-old baby girl is being evaluated for discharge. She was born by forceps-assisted vaginal delivery at 39 weeks gestation. The mother has no chronic medical conditions and attended all her prenatal visits. The mother’s blood type is A+. On day 1, the patient was noted to have a scalp laceration. Breastfeeding was difficult at first but quickly improved upon nurse assistance. The patient has had adequate wet diapers since birth. Upon physical examination, the resident notes the infant has scleral icterus and jaundiced skin. The scalp laceration noted on day 1 is intact without fluctuance or surrounding erythema. When the infant is slightly lifted from the bed and released, she spread out her arms, pulls them in, and exhibits a strong cry. Labs are drawn as shown below:\n\nBlood type: AB-\nTotal bilirubin 8.7 mg/dL\nDirect bilirubin 0.5 mg/dL\n\nSix hours later, repeat total bilirubin is 8.3 mg/dL. Which of the following is the next best step in the management of the baby’s condition?", "answer": "Observation", "options": {"A": "Coombs test", "B": "Exchange transfusion", "C": "Switch to baby formula", "D": "Observation", "E": "Phototherapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An autopsy of a 75-year-old man reveals obliterating endarteritis of the vasa vasorum of the aorta. Which of the following investigations will most likely be positive in this patient?", "answer": "Rapid plasma reagin (RPR)", "options": {"A": "Perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA)", "B": "Increased double-stranded (ds) DNA titer", "C": "Increased ketonuria", "D": "Increased serum creatinine", "E": "Rapid plasma reagin (RPR)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 43-year-old woman comes to the physician for a routine examination prior to starting a new job as a nurse. Over the past year, the patient has had mild shortness of breath and a cough productive of white sputum, particularly in the morning. She immigrated to the United States from South Africa with her parents 40 years ago. She received all appropriate immunizations during childhood, including the oral polio and BCG vaccine. She has smoked two packs of cigarettes daily for 30 years and drinks one glass of wine occasionally. Her only medication is a multivitamin. Her temperature is 36.5°C (97.7°F), pulse is 74/min, and blood pressure is 124/60 mm Hg. Bilateral wheezing is heard throughout both lung fields. A complete blood count and serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. Which of the following is the most appropriate next step to evaluate for tuberculosis in this patient?", "answer": "Interferon-gamma release assay", "options": {"A": "Tuberculin skin test", "B": "Sputum culture", "C": "X-ray of the chest", "D": "PCR of the sputum", "E": "Interferon-gamma release assay"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old G1P0000 presents for her first obstetric visit and is found to be at approximately 8 weeks gestation. She has no complaints aside from increased fatigue and occasional nausea. The patient is a recent immigrant from Africa and is currently working as a babysitter for several neighborhood children. One of them recently had the flu, and another is home sick with chickenpox. The patient has no immunization records and does not recall if she has had any vaccinations. She is sexually active with only her husband, has never had a sexually transmitted disease, and denies intravenous drug use. Her husband has no past medical history. Exam at this visit is unremarkable. Her temperature is 98.7°F (37.1°C), blood pressure is 122/76 mmHg, pulse is 66/min, and respirations are 12/min. Which of the following immunizations should this patient receive at this time?", "answer": "Intramuscular flu vaccine", "options": {"A": "Intranasal flu vaccine", "B": "Tetanus/Diphtheria/Pertussis vaccine", "C": "Hepatitis B vaccine", "D": "Varicella vaccine", "E": "Intramuscular flu vaccine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 54-year-old man is brought to the emergency department by his wife because of progressive nausea, vomiting, and right-sided flank pain for 2 days. The pain is colicky and radiates to the groin. He has a history of gout and type 2 diabetes mellitus. Current medications are metformin and allopurinol. He recently began taking large amounts of a multivitamin supplement after he read on the internet that it may help to prevent gout attacks. Physical examination shows right-sided costovertebral angle tenderness. Oral examination shows dental erosions. A CT scan of the abdomen shows an 8-mm stone in the right proximal ureter. Microscopic examination of a urine sample shows bipyramidal, envelope-shaped crystals. An increased serum concentration of which of the following is the most likely cause of this patient’s symptoms?", "answer": "Vitamin C", "options": {"A": "Vitamin A", "B": "Vitamin B3", "C": "Vitamin E", "D": "Vitamin C", "E": "Uric acid"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old man comes to the physician because of decreased hearing in his right ear for the past 4 months. During this period, he has also had multiple episodes of dizziness and a constant ringing noise in his right ear. Over the past 5 weeks, he has also noticed scant amounts of right-sided ear discharge. He has a history of multiple ear infections since childhood that were treated with antibiotics. Vital signs are within normal limits. Otoscopic examination shows a white pearly mass behind the right tympanic membrane. Placing a 512 Hz tuning fork in the center of the forehead shows lateralization to the right ear. Which of the following is the most appropriate therapy for this patient's symptoms?", "answer": "Surgical excision", "options": {"A": "Topical ciprofloxacin", "B": "Radiation therapy", "C": "Systemic corticosteroids", "D": "Fitting for hearing aids", "E": "Surgical excision"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 73-year-old woman presents to the emergency department with diffuse abdominal pain, nausea, and vomiting. Her daughter who accompanies her says she was in her usual state of health until two days ago when she started to complain of abdominal pain and was unable to tolerate oral intake. She has hypertension, congestive heart failure, atrial fibrillation, and osteoarthritis. She underwent an exploratory laparotomy for an ovarian mass a year ago where a mucinous cystadenoma was excised. Her medications include aspirin, nifedipine, lisinopril, metoprolol, warfarin, and Tylenol as needed for pain. She does not drink alcohol or smoke cigarettes. She appears ill and disoriented. Her temperature is 37.9°C (100.3°F), blood pressure is 102/60 mm Hg, pulse is 110/min and irregular, and respirations are 16/min. Examination shows diffuse tenderness to palpation of the abdomen. The abdomen is tympanitic on percussion. Bowel sounds are hyperactive. The lungs are clear to auscultation bilaterally. There is a soft crescendo-decrescendo murmur best auscultated in the right second intercostal space. Laboratory studies show:\nHemoglobin 10.2 g/dL\nLeukocyte count 14,000/mm3\nPlatelet count 130,000/mm3\nProthrombin time 38 seconds\nINR 3.2\nSerum\nNa+ 132 mEq/dL\nK+ 3.6 mEq/dL\nCl- 102 mEq/dL\nHCO3- 19 mEq/dL\nUrea nitrogen 36 mg/dl\nCreatinine 2.3 mg/dL\nLactate 2.8 mEq/dL (N= 0.5-2.2 mEq/dL)\nAn x-ray of the abdomen shows multiple centrally located dilated loops of gas filled bowel. There is no free air under the diaphragm. A nasogastric tube is inserted and IV fluids and empiric antibiotic therapy are started. Emergent exploratory laparotomy is planned. Which of the following is the next best step in management?\"", "answer": "Administer fresh frozen plasma and Vitamin K", "options": {"A": "Administer unfractionated heparin", "B": "Administer protamine sulfate", "C": "Administer fresh frozen plasma and Vitamin K", "D": "Administer platelet concentrate", "E": "Administer recombinant activated factor VII"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "You are asked to examine a 1-year-old child brought to the emergency department by his sister. The sister reports that the child has been acting strangely since that morning after \"getting in trouble\" for crying. The child appears lethargic and confused and is noted to have a cigarette burn on his forearm. Emergency head CT reveals a subdural hematoma. Which of the following additional findings is most likely?", "answer": "Bilateral retinal hemorrhages", "options": {"A": "Posterior rib fracture", "B": "Bilateral retinal hemorrhages", "C": "Skull fracture", "D": "Burns to buttocks", "E": "Epidural hematoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Paramedics respond to a call regarding an 18-year-old male with severe sudden-onset heart palpitations. The patient reports symptoms of chest pain, fatigue, and dizziness. Upon examination, his heart rate is 175/min and regular. His blood pressure is 110/75 mm Hg. Gentle massage below the level of the left mandible elicits an immediate improvement in the patient, as his heart rate returns to 70/min. What was the mechanism of action of this maneuver?", "answer": "Slowing conduction in the AV node", "options": {"A": "Increasing the refractory period in ventricular myocytes", "B": "Increasing sympathetic tone in systemic arteries", "C": "Decreasing the length of phase 4 of the SA node myocytes", "D": "Slowing conduction in the AV node", "E": "Decreasing the firing rate of carotid baroreceptors"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old female visits her primary care physician with 2+ pitting edema in her legs. She takes no medications and does not use alcohol, tobacco, or illicit drugs. 4.5 grams of protein are collected during 24-hour urine excretion. A kidney biopsy is obtained. Examination with light microscopy shows diffuse thickening of the glomerular basement membrane. Electron microscopy shows subepithelial spike and dome deposits. Which of the following is the most likely diagnosis:", "answer": "Membranous nephropathy", "options": {"A": "Minimal change disease", "B": "Postinfectious glomerulonephritis", "C": "Focal segmental glomerulosclerosis", "D": "Rapidly progressive glomerulonephritis", "E": "Membranous nephropathy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old woman, gravida 1, para 0, at 10 weeks' gestation comes to the physician for her initial prenatal visit. She has no history of serious illness, but reports that she is allergic to penicillin. Vital signs are within normal limits. The lungs are clear to auscultation, and cardiac examination shows no abnormalities. Transvaginal ultrasonography shows an intrauterine pregnancy with no abnormalities. The fetal heart rate is 174/min. Routine prenatal laboratory tests are drawn. Rapid plasma reagin (RPR) test is 1:128 and fluorescent treponemal antibody absorption test (FTA-ABS) is positive. Which of the following is the most appropriate next step in management?", "answer": "Administer penicillin desensitization dose", "options": {"A": "Administer therapeutic dose of intramuscular penicillin G", "B": "Administer intravenous ceftriaxone", "C": "Administer penicillin desensitization dose", "D": "Administer oral azithromycin", "E": "Perform oral penicillin challenge test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old man is brought to the emergency room by police after being found passed out on the sidewalk. He is intermittently alert and smells strongly of alcohol. He is unable to provide a history, but an electronic medical record search reveals that the patient has a history of alcohol abuse and was seen in the emergency room twice in the past year for alcohol intoxication. Further review of the medical record reveals that he works as a day laborer on a farm. His temperature is 98.8°F (37.1°C), blood pressure is 122/78 mmHg, pulse is 102/min, and respirations are 14/min. On examination, he is somnolent but arousable. He has vomitus on his shirt. He is given intravenous fluids and provided with supportive care. He vomits twice more and is discharged 6 hours later. However, 6 days after discharge, he presents to the emergency room again complaining of shortness of breath and fever. His temperature is 102°F (38.9°C), blood pressure is 100/58 mmHg, pulse is 116/min, and respirations are 24/min. The patient is actively coughing up foul-smelling purulent sputum. Which of the following is the most likely cause of this patient’s current symptoms?", "answer": "Bacteroides melaninogenicus", "options": {"A": "Bacteroides melaninogenicus", "B": "Coxiella burnetii", "C": "Francisella tularensis", "D": "Legionella pneumonphila", "E": "Mycoplasma pneumoniae"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman who resides in an area endemic for chloroquine-resistant P. falciparum malaria presents to the physician with fatigue, malaise, and episodes of fever with chills over the last 5 days. She mentions that she has episodes of shivering and chills on alternate days that last for approximately 2 hours, followed by high-grade fevers; then she has profuse sweating and her body temperature returns to normal. She also mentions that she is currently in her 7th week of pregnancy. The physical examination reveals the presence of mild splenomegaly. A peripheral blood smear confirms the diagnosis of P. falciparum infection. Which of the following is the most appropriate anti-malarial treatment for the woman?", "answer": "Quinine sulfate plus clindamycin", "options": {"A": "Mefloquine only", "B": "Chloroquine phosphate plus primaquine", "C": "Quinine sulfate plus clindamycin", "D": "Quinine sulfate plus doxycycline", "E": "Quinine sulfate plus sulfadoxine-pyrimethamine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 8-year-old boy presents to your office for a routine well-child visit. Upon physical examination, he is found to have a harsh-sounding, holosystolic murmur that is best appreciated at the left sternal border. The murmur becomes louder when you ask him to make fists with his hands. Which of the following is the most likely explanation for these findings?", "answer": "Ventricular septal defect", "options": {"A": "Aortic stenosis", "B": "Tricuspid atresia", "C": "Pulmonary hypertension", "D": "Ventricular septal defect", "E": "Left ventricular hypertrophy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old woman, gravida 5, para 5, comes to the physician for the evaluation of decreased sexual desire for approximately 6 months. She has been sexually active with her husband but reports that she has no desire in having sexual intercourse anymore. She states that she feels guilty and is worried about losing her husband if this problem goes on for a longer period of time. She also reports that they have had several fights recently due to financial problems. She has problems going to sleep and wakes up often, and is tired throughout the day. One year ago, the patient underwent hysterectomy with bilateral salpingo-oophorectomy due to uterine prolapse. Her last menstrual period was 2 years ago. She does not smoke. She drinks 3–4 glasses of wine daily. Vital signs are within normal limits. Physical examination shows no abnormalities except for an enlarged liver. Which of the following most likely explains this patient's loss of libido?", "answer": "Decreased testosterone", "options": {"A": "Chronic alcohol intake", "B": "Major depressive disorder", "C": "Decreased testosterone", "D": "Elevated prolactin", "E": "Stress"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old previously healthy woman presents to the emergency room with right leg pain and difficulty breathing. She recently returned from a trip to Alaska and noticed her leg started to swell when she got home. Her medications include a multivitamin and oral contraceptives. She is diagnosed with a deep venous thrombosis complicated by a pulmonary embolism and started on anticoagulation. She remains stable and is discharged on the third hospital day with long-term anticoagulation. During the 2 month follow-up visit, the patient’s lab results are as follows:\n\nHemoglobin: 14 g/dL\nHematocrit: 44%\nLeukocyte count: 5,000/mm^3 with normal differential\nPlatelet count: 300,000/mm^3\nProthrombin time: 23 seconds\nPartial thromboplastin time (activated): 20 seconds\nBleeding time: 4 minutes\n\nWhich of the following factors is initially activated in the target pathway for her long-term treatment?", "answer": "VII", "options": {"A": "II", "B": "V", "C": "VII", "D": "IX", "E": "X"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old man presents to the emergency department after fainting at his investment banking office. He states that he has experienced intermittent headaches since high school, but has never fainted. He reports eating multiple small meals regularly throughout the day. He further notes that multiple family members have frequently complained about headaches. Physical exam reveals a well-nourished, well-built, afebrile man with BP 170/80, HR 55, RR 10. Chemistries reveal Na 147, K 3, Cl 110, HCO3 30, BUN 25, Cr 1.1, glucose 120. A biopsy of the tissue most likely at issue in this patient will reveal the most abnormal cellular amounts of which of the following?", "answer": "smooth endoplasmic reticulum", "options": {"A": "rough endoplasmic reticulum", "B": "lysosome", "C": "peroxisome", "D": "smooth endoplasmic reticulum", "E": "beta-adrenergic receptor"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old man presents to the emergency department with nausea and vomiting. He says symptoms onset 4 hours ago and is progressively worsening. He denies any hematemesis. Past medical history is significant for a recent negative screening colonoscopy that was performed due to a family history of colon cancer. His vital signs are significant for a temperature of 39.5°C (103.1°F). Physical examination is unremarkable. A contrast CT of the abdomen reveals a colonic perforation. Laboratory findings are significant for an elevated WBC count with a predominant left shift, a decreased platelet count, increased PT and PTT, slightly decreased hemoglobin/hematocrit, and prolonged bleeding time. Which of the following is most closely related to this patient’s prolonged bleeding time?", "answer": "Fibrinogen", "options": {"A": "GpIIb/IIIa", "B": "Vitamin K", "C": "Fibrinogen", "D": "COX-1 and COX-2", "E": "Giant platelets"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A group of investigators is evaluating the diagnostic properties of a new blood test that uses two serum biomarkers, dityrosine and Nε-carboxymethyl-lysine, for the clinical diagnosis of autism spectrum disorder (ASD) in children. The test is considered positive only if both markers are found in the serum. 50 children who have been diagnosed with ASD based on established clinical criteria and 50 children without the disorder undergo testing. The results show:\nDiagnosis of ASD No diagnosis of ASD\nTest positive 45 15\nTest negative 5 35\nWhich of the following is the specificity of this new test?\"", "answer": "70%", "options": {"A": "30%", "B": "10%", "C": "88%", "D": "70%", "E": "90%"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old man is brought to the local emergency room in severe respiratory distress. The patient is an industrial chemist and was working in his lab with a new partner when a massive chemical spill occurred releasing fumes into their workspace. The patient and his lab partner attempted to clean up the spill before they realized it was too large for them to handle. They were not wearing protective equipment at the time, except for a pair of goggles. The fumes caused them both to begin coughing; however, this patient has a history significant for asthma. His condition worsened, which prompted lab management to call for an ambulance. On arrival at the emergency room, the patient’s respiratory rate is 42/min and oxygen saturation is 96% on room air. He is unable to speak on account of his coughing. He is clearly using accessory muscles with inspiration. A pulmonary exam reveals bilateral wheezes. He is given multiple nebulizer treatments of albuterol and is started on intravenous (IV) methylprednisolone. After 2 successive nebulizer treatments, the arterial blood gas test result shows pH 7.36, partial pressure of carbon dioxide (PCO2) 41 mm Hg, and partial pressure of oxygen (PO2) 79 mm Hg. He is now able to speak and the respiratory rate is 32/min. Which of the following is the best next step in this patient’s management?", "answer": "Continue to administer albuterol", "options": {"A": "Administer IV epinephrine", "B": "Administer IV prednisone in addition to IV methylprednisolone", "C": "Continue to administer albuterol", "D": "Switch from nebulized albuterol to nebulized ipratropium", "E": "Intubate the patient and begin mechanical ventilation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Blood cultures are sent to the laboratory. Antibiotic treatment is started. Blood cultures confirm an infection with methicillin-susceptible Staphylococcus epidermidis. Which of the following is the most appropriate next step in management?", "answer": "Intravenous nafcillin + rifampin for 6 weeks + gentamicin for 2 weeks", "options": {"A": "Oral penicillin V + gentamicin for 4 weeks", "B": "Intravenous ampicillin + rifampin + ceftriaxone for 2 weeks", "C": "Oral gentamicin + ceftriaxone for 4 weeks", "D": "Oral amoxicillin for 6 weeks", "E": "Intravenous nafcillin + rifampin for 6 weeks + gentamicin for 2 weeks"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-week-old child is brought to his pediatrician for a physical exam and hepatitis B booster. The boy was born at 39 weeks gestation via spontaneous vaginal delivery to a 19-year-old G-1-P-1. He was previously up to date on all vaccines and is mildly delayed in some developmental milestones. His mother is especially concerned with colic, as the boy cries endlessly at night. During the conversation, the infant's mother breaks down and starts crying and complaining about how tired she is and how she has no support from her family. She admits to repeatedly striking the infant in an effort to stop his crying. On physical exam, the infant’s vitals are normal. The child appears cranky and begins to cry during the exam. The infant's backside is swollen, red, and tender to touch. Which of the following is the best response to this situation?", "answer": "Contact child protective services", "options": {"A": "Confront the mother directly", "B": "Contact child protective services", "C": "Recommend treating the colic with a few drops of whiskey", "D": "Encourage the mother to take a class on parenting", "E": "Contact the hospital ethics committee"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 16-year-old girl presents to the emergency room with her 8-month-old daughter for evaluation of “turning blue when she cries.” The baby is found to have an atrial septal defect that is causing a left to right shunt, resulting in cyanosis and pulmonary hypertension. Surgical intervention is indicated; however, the mother wants to go to another hospital for a second opinion. Which of the following is the most appropriate next course of action?", "answer": "Allow the mother to take the patient for a second opinion.", "options": {"A": "Consult the mother's parents because she is a minor.", "B": "Contact child protective services.", "C": "Perform the surgery.", "D": "Allow the mother to take the patient for a second opinion.", "E": "Obtain a court order to perform the surgery."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man presents to the outpatient clinic with a swollen and painful toe. The pain intensity increased further after he went to a party last night. Which of the following is the drug of choice for the treatment of this patient's condition?", "answer": "Indomethacin", "options": {"A": "Aspirin", "B": "Probenecid", "C": "Rasburicase", "D": "Indomethacin", "E": "Allopurinol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old woman, gravida 2, para 1, at 40 weeks' gestation is admitted to the hospital in active labor. Pregnancy has been complicated by iron deficiency anemia, which was treated with iron supplements. Her first pregnancy and vaginal delivery were uncomplicated. There is no personal or family history of serious illness. Her pulse is 90/min, respirations are 15/min, and blood pressure is 130/80 mm Hg. The abdomen is nontender and contractions are felt. Ultrasonography shows that the fetal long axis is at a right angle compared to the long axis of the maternal uterus. The fetal heart rate is 140/min and is reactive with no decelerations. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Cesarean section", "options": {"A": "Administration of oxytocin and normal vaginal birth", "B": "Vacuum-assisted delivery", "C": "Lateral positioning of the mother", "D": "Cesarean section", "E": "External cephalic version"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A scientist is studying the process by which innate immune cells are able to respond to damage and pathogen infiltration. Specifically, she examines patients with an immunodeficiency where they are unable to respond to local infections. She notices that these patients do not produce pustulant fluid and do not have recruitment of immune cells in the first several hours of inflammation. Examining neutrophils within these patients reveals that they are able to slow their movement in a flow chamber by loosely attaching to purified vessel tissues. Subsequently, she shows that the neutrophils attach tightly to these vessel walls and move across the walls to the other side. Finally, when different levels of pathogenic proteins are placed on two sides of a purified vessel wall, the neutrophils from this patient do not exhibit a preference between the two sides. The step of neutrophil recruitment that is most likely defective in this patient involves which of the following mediators?", "answer": "C5a", "options": {"A": "C5a", "B": "Integrins", "C": "ICAM proteins", "D": "Nitric oxide", "E": "Selectins"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 1-month-old boy is brought to the physician because of a 5-day history of generalized fatigue and multiple episodes of vomiting which is most pronounced after formula feeding. His vomiting progressed from 2–3 episodes on the first day to 6–8 episodes at present. The vomitus is whitish in color. The mother reports that he has been very hungry after each episode of vomiting. The patient was born at 38 weeks' gestation and weighed 3100 g (6 lb 13 oz); he currently weighs 3500 g (7 lb 11 oz). He appears irritable. His temperature is 37.1°C (98.8°F), pulse is 130/min, respirations are 43/min, and blood pressure is 74/36 mm Hg. Examination shows dry mucous membranes. The abdomen is soft and not distended. There is a round mass palpable in the epigastric region. The liver is palpated 1 cm below the right costal margin. Laboratory studies show:\nHemoglobin 15.3 g/dL\nLeukocyte count 6300/mm3\nPlatelet count 230,000/mm3\nSerum\nNa+ 133 mEq/L\nK+ 3.4 mEq/L\nCl- 92 mEq/L\nGlucose 77 mg/dL\nCreatinine 1.0 mg/dL\nA urinalysis shows a decreased pH. Which of the following is the most appropriate next step in the management of this patient?\"", "answer": "Administer IV 0.9% NaCl and replace electrolytes", "options": {"A": "Administer IV 0.9% NaCl and replace electrolytes", "B": "Perform emergency pyloromyotomy", "C": "Perform upper GI endoscopy", "D": "Obtain CT scan of the abdomen with contrast", "E": "Measure serum cortisol levels"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "In order to study the association between coffee drinking and the subsequent development of lung cancer, a group of researchers decides to carry out a multicentric case-control study with a large number of participants–800 with a diagnosis of lung cancer, and 800 as age-adjusted controls. According to the results outlined in table 1 (below), 80% of those with lung cancer were regular coffee drinkers, resulting in an odds ratio of 23.\n  Lung cancer present Lung cancer absent\nCoffee drinking 640 120\nNo coffee drinking  160 680\nTable: Contingency table of coffee drinking in relation to the presence of lung cancer\nThe researchers concluded from this that regular consumption of coffee is strongly linked to the development of lung cancer. Which of the following systematic errors did they not take into account?", "answer": "Confounding bias", "options": {"A": "Observer bias", "B": "Selection bias", "C": "Confounding bias", "D": "Attrition bias", "E": "Information bias"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 48-hour-old newborn presents in respiratory distress. He is gasping for breath in the neonatal intensive care unit (NICU) and has had a fever for the past 2 days with a temperature ranging between 37.2°C (99.0°F) and 38.6°C (101.5°F). He also has not been feeding well and seems to be lethargic. The patient was delivered normally at 36 weeks of gestation. His mother had a premature rupture of membranes, which occurred with her last pregnancy, as well. No history of infection during pregnancy. On physical examination, a bulging anterior fontanelle is noticed, along with tensing of the extensor muscles. A lumbar puncture is performed, and CSF analysis is pending. Which of the following would be the best course of treatment in this patient?", "answer": "Ampicillin and gentamicin", "options": {"A": "Ampicillin and gentamicin", "B": "Ampicillin and cefotaxime", "C": "Ampicillin and acyclovir", "D": "Ampicillin and ticarcillin", "E": "Ampicillin and sulbactam"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 8-year-old boy is brought to the clinic by his father for an annual well-check. His dad reports that he has been “difficult to handle” as he would not listen and follow instructions at home. “Telling him to sit still and do something is just so hard,” the father says. His teacher also reports difficulties in the classroom where the child would talk out of turn and interrupt the class intermittently by doing something else. His grades have been suffering as a result. Otherwise, the patient has been healthy and up to date on his immunizations. What is the best course of management for this patient?", "answer": "Methylphenidate", "options": {"A": "Family therapy", "B": "Haloperidol", "C": "Methylphenidate", "D": "Psychodynamic therapy", "E": "Reassurance"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 30-year-old woman comes to the physician because of a 3-month history of progressive shortness of breath and nonproductive cough. She also complains of constipation and fatigue during the same time period. She has not traveled recently or been exposed to any sick contacts. Physical examination shows injected conjunctivae and tender, erythematous nodules on both shins. The lungs are clear to auscultation. An x-ray of the chest is shown. Which of the following additional findings is most likely in this patient?", "answer": "Low serum CD4+ T-cell count", "options": {"A": "Positive interferon-gamma release assay", "B": "Low serum angiotensin-converting enzyme levels", "C": "Elevated serum parathyroid hormone levels", "D": "Low serum CD4+ T-cell count", "E": "Positive anti-dsDNA antibody testing"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old female reports having a positive home pregnancy test result 9 weeks ago. She presents today with vaginal bleeding and complains of recent onset abdominal pain. Ultrasound of the patient’s uterus is included as Image A. Subsequent histologic analysis (Image B) reveals regions of both normal as well as enlarged trophoblastic villi. Which of the following is the most likely karyotype associated with this pregnancy?", "answer": "69 XXY", "options": {"A": "46 XX, both of maternal origin", "B": "46 XY, both of paternal origin", "C": "69 XXY", "D": "47 XXY", "E": "45 XO"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A mother brings her infant for a regular well-child check-up with the pediatrician. During the routine developmental examination, the physician notes that the child is looking at him with his head lifted upwards when he is about to pick up the child from the table. At what age is it common to begin to observe this finding in a child, assuming that the child is developmentally normal?", "answer": "2 months", "options": {"A": "4 months", "B": "2 months", "C": "6 months", "D": "9 months", "E": "12 months"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the physician because of a 2-month history of headaches, facial numbness, recurrent epistaxis, and a 5-kg (11-lb) weight loss. He recently immigrated from Hong Kong. Examination shows right-sided cervical lymphadenopathy. Endoscopy shows an exophytic nasopharyngeal mass. Histologic examination of a biopsy specimen of the mass shows sheets of undifferentiated cells with nuclear pleomorphism and abundant mitotic figures. The patient most likely acquired the causal pathogen of his nasopharyngeal mass via which of the following routes of transmission?", "answer": "Transfer of saliva", "options": {"A": "Sexual contact", "B": "Tick bite", "C": "Transfer of saliva", "D": "Fecal-oral", "E": "Mother to baby"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 8-year-old boy is brought to the physician by his parents for blurry vision for the past 2 months. He is at the 97th percentile for height and 25th percentile for weight. Physical examination shows joint hypermobility, a high-arched palate, and abnormally long, slender fingers and toes. Slit lamp examination shows superotemporal lens subluxation bilaterally. This patient's findings are most likely caused by a defect in which of the following structural proteins?", "answer": "Fibrillin", "options": {"A": "Laminin", "B": "Type III collagen", "C": "Fibrillin", "D": "Type I collagen", "E": "Keratin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old man presents to a medical office with painful micturition for 2 weeks. He denies any other symptoms. The past medical history is unremarkable. He has been a smoker most of his life, smoking approx. 1 pack of cigarettes every day. The physical examination is benign. A urinalysis shows an abundance of red blood cells. A cystoscopy is performed, which reveals a slightly erythematous area measuring 1.5 x 1 cm on the bladder mucosa. A biopsy is obtained and microscopic evaluation shows cells with an increased nuclear: cytoplasmic ratio and marked hyperchromatism involving the full thickness of the epithelium, but above the basement membrane. Which of the following best describes the biopsy findings?", "answer": "Urothelial carcinoma-in-situ", "options": {"A": "Reactive atypia", "B": "Microinvasion", "C": "Urothelial metaplasia", "D": "Urothelial carcinoma-in-situ", "E": "Urothelial hyperplasia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 13-year-old girl is brought to the physician by her father because of a 1-month history of pain in her right knee. She is a competitive volleyball player and has missed several games recently due to pain. Examination shows swelling distal to the right knee joint on the anterior surface of the proximal tibia; there is no overlying warmth or deformity. Extension of the right knee against resistance is painful. Which of the following structures is attached to the affected anterior tibial area?", "answer": "Patellar ligament", "options": {"A": "Anterior cruciate ligament", "B": "Patellar ligament", "C": "Quadriceps tendon", "D": "Iliotibial band", "E": "Pes anserinus tendon"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old woman presents the following significant and unintentional weight loss. She denies any personal history of blood clots in her past, but she says that her mother has also had to be treated for pulmonary embolism in the recent past. She also mentions that she had been struggling with her weight, so she was initially content with losing the weight, but her daughter convinced her to come to the office to be checked out. Her past medical history is significant for preeclampsia, hypertension, polycystic ovarian syndrome, and hypercholesterolemia. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and she currently denies any illicit drug use, although she has a remote past of injection drug use with heroin. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 111/min and irregular, and respiratory rate 17/min. On physical examination, her pulses are bounding and complexion is pale, but breath sounds remain clear. Oxygen saturation was initially 91% on room air and electrocardiogram (ECG) showed atrial fibrillation. Upon further discussion with the patient, her physician discovers that she is having some cognitive difficulty. Her leukocyte count is elevated to 128,000/mm3, and she has elevated lactate dehydrogenase (LDH), uric acid, and B-12 levels. A BCR-ABL translocation is present, as evidenced by the Philadelphia chromosome. What is the most likely diagnosis for this patient?", "answer": "Chronic myelogenous leukemia", "options": {"A": "Acute lymphocytic leukemia", "B": "Acute myelogenous leukemia", "C": "Chronic lymphocytic leukemia", "D": "Chronic myelogenous leukemia", "E": "Hairy cell leukemia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 75-year-old man presents to the physician with a complaint of persistent back pain. The patient states that the pain has been constant and occurs throughout the day. He says that he has also been experiencing greater fatigue when carrying out his daily activities. On review of systems, the patient notes that he lost more than 10 pounds in the past month despite maintaining his usual diet and exercising less often due to his fatigue. Physical exam is notable for a systolic murmur at the right sternal border, mild crackles at the bases of both lungs, and tenderness to palpation of his lumbar spine. Laboratory values are below:\n\nSerum:\nNa+: 141 mEq/L\nCl-: 101 mEq/L\nK+: 4.2 mEq/L\nHCO3-: 23 mEq/L\nBUN: 20 mg/dL\nGlucose: 101 mg/dL\nCreatinine: 1.6 mg/dL\nCa2+: 12.8 mg/dL\n\nA peripheral blood smear is ordered for the patient’s work-up. Which of the following would be the most likely finding on peripheral blood smear?", "answer": "Rouleaux formation", "options": {"A": "Atypical lymphocytes", "B": "Echinocytes", "C": "Rouleaux formation", "D": "Schistocytes", "E": "Target cells"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 8-year-old girl is brought into your clinic with a 5 day history of decreased oral intake, body aches and lymphadenopathy. She has no significant medical history. Upon further questioning you find that the patient frequently plays outside, where she enjoys chasing the neighborhood cats and dogs. She has had no recent sick contacts or travel to foreign countries. The patients vital signs are: temperature 100.4F, HR 80, BP 105/75 and RR 15. Physical exam is significant for a 1-cm erythematous and tender lymph node in the right posterior cervical area (Figure 1). There is a nearly healed scratch in the right occipital region. What is the most likely diagnosis for this patient?", "answer": "Bartonella henselae infection", "options": {"A": "Acute lymphoblastic leukemia (ALL)", "B": "Extrapulmonary tuberculosis", "C": "Toxoplasmosis gandii infection", "D": "Bartonella henselae infection", "E": "Staphlococcal aureus adenitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old G2P1 female with a history of hypertension presents to the emergency room at 33 weeks with headache and blurry vision. On exam, her vitals include BP 186/102 mmHg, HR 102 beats per minute, RR 15 breaths per minute, and T 98.9 degrees Fahrenheit. She undergoes an immediate Caesarian section, and although she is noted to have large-volume blood loss during the procedure, the remainder of her hospital course is without complications. Four weeks later, the patient returns to her physician and notes that she has had blurry vision and has not been able to lactate. A prolactin level is found to be 10 ng/mL (normal: 100 ng/mL). Which of the following is the most appropriate next step?", "answer": "Brain MRI", "options": {"A": "Galactogram", "B": "Observation of maternal-child interactions", "C": "Brain MRI", "D": "Head CT", "E": "Breast ultrasound"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A female child presents to her pediatrician for a well child visit. Her mother reports that she is eating well at home and sleeping well throughout the night. She can jump and walk up and down stairs with both feet on each step. In the doctor’s office, the patient builds a six-cube tower and imitates a circle. She seems to have a vocabulary of over 50 words that she uses in two-word sentences. Her mother reports that the patient enjoys playing near other children and sometimes argues over toys with her older brother. On physical exam, she appears well developed and well nourished, and she is following along her growth curves. The child is assessed as developmentally normal.\n\nWhich of the following is an additional milestone associated with this child’s age?", "answer": "Follows two-step commands", "options": {"A": "Balances on one foot", "B": "Cuts with scissors", "C": "Follows two-step commands", "D": "Points to one body part", "E": "Turns pages in book"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old woman comes to the emergency department because of a 1-day history of severe pain in her left knee. To lose weight, she recently started jogging for 30 minutes a few times per week. She has type 2 diabetes mellitus and hypertension treated with metformin and chlorothiazide. Her sister has rheumatoid arthritis. She is sexually active with two partners and uses condoms inconsistently. On examination, her temperature is 38.5°C (101.3°F), pulse is 88/min, and blood pressure is 138/87 mm Hg. The left knee is swollen and tender to palpation with a significantly impaired range of motion. A 1.5-cm, painless ulcer is seen on the plantar surface of the left foot. Which of the following is most likely to help establish the diagnosis?", "answer": "Perform arthrocentesis", "options": {"A": "Perform MRI of the knee", "B": "Perform arthrocentesis", "C": "Measure HLA-B27", "D": "Measure rheumatoid factor", "E": "Perform ultrasonography of the knee"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man comes to the physician with intermittent bloody diarrhea over the past 2 months. He has occasional abdominal pain. His symptoms have not improved over this time. He has no history of a serious illness and takes no medications. His blood pressure is 110/70 mm Hg, pulse is 75/min, respirations are 14/min, and temperature is 37.8°C (100.0°F). Deep palpation of the abdomen shows mild tenderness in the right lower quadrant. Colonoscopy shows diffuse erythema with a sandpaper pattern involving the rectosigmoid and descending colon, with normal mucosa of the rest of the colon. Biopsy shows involvement of the mucosal and submucosal layers with distortion of crypt architecture and crypt abscess formation. This patient is most likely to develop which of the following hepatobiliary diseases?", "answer": "Primary sclerosing cholangitis", "options": {"A": "Cholangiocarcinoma", "B": "Cholelithiasis", "C": "Hepatocellular carcinoma", "D": "Primary biliary cirrhosis", "E": "Primary sclerosing cholangitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 48-year-old woman presents to her primary care physician with the complaints of persistent fatigue, dizziness, and weight loss for the past 3 months. She has hypothyroidism for 15 years and takes thyroxine replacement. Her blood pressure is 90/60 mm Hg in a supine position and 65/40 mm Hg while sitting, temperature is 36.8°C (98.2°F) and pulse is 75/min. On physical examination, there is a mild increase in thyroid size, with a rubbery consistency. Her skin shows diffuse hyperpigmentation, more pronounced in the oral mucosa and palmar creases. The morning serum cortisol test is found to be 3 µg/dL. Which of the following is the best next step in this case?", "answer": "Adrenocorticotropic hormone (ACTH) stimulation test", "options": {"A": "Serum adrenocorticotropic hormone (ACTH)", "B": "Plasma aldosterone", "C": "Adrenocorticotropic hormone (ACTH) stimulation test", "D": "Adrenal imaging", "E": "21-hydroxylase antibodies"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl comes to your outpatient clinic. She is sexually active with multiple partners and requests a prescription for oral contraceptive pills. A urine pregnancy test in your office is negative. Which of the following is the most appropriate next step?", "answer": "Recommend sexually-transmitted infection screening and provide the requested prescription", "options": {"A": "Contact the patient's parents to obtain consent", "B": "Recommend sexually-transmitted infection screening and provide the requested prescription", "C": "Refer the patient for counseling and recommend sexually-transmitted infection screening", "D": "Perform urine drug screen", "E": "Advise against oral contraceptive medications and recommend condom use instead"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A newborn infant presents with severe weakness. He was born to a G1P1 mother at 40 weeks gestation with the pregnancy attended by a midwife. The mother's past medical history is unremarkable. She took a prenatal vitamin and folic acid throughout the pregnancy. Since birth, the child has had trouble breastfeeding despite proper counseling. He also has had poor muscle tone and a weak cry. His temperature is 99.5°F (37.5°C), blood pressure is 57/38 mmHg, pulse is 150/min, respirations are 37/min, and oxygen saturation is 96% on room air. Physical exam reveals poor muscle tone. The patient's sucking reflex is weak, and an enlarged tongue is noted. An ultrasound is performed, and is notable for hypertrophy of the myocardium. Which of the following is the most likely diagnosis?", "answer": "Acid maltase deficiency", "options": {"A": "Acid maltase deficiency", "B": "Clostridium botulinum infection", "C": "Clostridium tetani infection", "D": "Familial hypertrophic cardiomyopathy", "E": "Spinal muscular atrophy type I disease"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-week-old infant is brought to the emergency room because of 4 episodes of bilious vomiting and inconsolable crying for the past 3 hours. Abdominal examination shows no abnormalities. An upper GI contrast series shows the duodenojejunal junction to the right of the vertebral midline; an air-filled cecum is noted in the right upper quadrant. Which of the following is the most likely cause of this patient's condition?", "answer": "Incomplete intestinal rotation", "options": {"A": "Failure of duodenal recanalization", "B": "Incomplete intestinal rotation", "C": "Arrested rotation of ventral pancreatic bud", "D": "Hypertrophy and hyperplasia of the pyloric sphincter", "E": "Resorption of a small bowel segment"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 43-year-old male is admitted to the hospital for a left leg cellulitis. He is being treated with clindamycin and is recovering nicely. On the second day of his admission, a nurse incorrectly administers 100 mg of metoprolol which was intended for another patient with the same last name. The error is not discovered until the next day, at which time it is clear that the patient has suffered no ill effects of the medication and is not aware that an error has occurred. What is the proper course of action of the attending physician?", "answer": "Immediately disclose the error to the patient", "options": {"A": "Immediately disclose the error to the patient", "B": "Notify hospital administration but do not notify the patient as no ill effects occurred", "C": "Do not disclose the error to the patient as no ill effects occurred", "D": "Tell the nurse who administered the drug to notify the patient an error has occurred", "E": "Make a note in the patient's chart an error has occurred but do not disclose the error to the patient"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman presents to her primary care physician with 2 weeks of abdominal pain. She says that the pain is squeezing in character and gets worse after she eats food. The pain is particularly bad after she eats dairy products so she has begun to avoid ice cream and cheese. Furthermore, she has noticed that she has been experiencing episodes of nausea associated with abdominal pain in the last 4 days. Physical exam reveals tenderness to palpation and rebound tenderness in the right upper quadrant of the abdomen. The molecule that is most likely responsible for the increased pain this patient experiences after eating fatty foods is most likely secreted by which of the following cells?", "answer": "I cells", "options": {"A": "D cells", "B": "G cells", "C": "I cells", "D": "P/D1 cells", "E": "S cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old woman comes to clinic complaining of pain with chewing solid foods. She reports that she has been feeling unwell lately, with pains in her shoulders and hips, and she has lost five pounds in the past few months. Her vital signs are T 39C, RR 18 breaths/min, HR 95 bpm, BP 120/65 mmHg. When you ask her to stand from her chair to get on the exam table she moves stiffly but displays preserved proximal muscle strength. Another potential symptom or sign of this disease could be:", "answer": "Blindness", "options": {"A": "Violaceous rash across the eyelids", "B": "Blindness", "C": "Easily sunburned on face and hands", "D": "Hemoptysis", "E": "Thickened, tight skin on the fingers"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 1800-g (4.0-lb) male newborn is delivered to a 26-year-old woman, gravida 2, para 1, at 33 weeks' gestation. The Apgar scores are 7 at 1 minute and 8 at 5 minutes. The pregnancy was complicated by iron deficiency anemia. The mother has no other history of serious illness. She has smoked one-half pack of cigarettes daily for the past 10 years. She does not drink alcohol. She has never used illicit drugs. Pregnancy and delivery of her first child were complicated by placenta previa. The mother has received all appropriate immunizations. It is most appropriate for the physician to recommend which of the following to the mother regarding her son's immunizations?", "answer": "Give first dose of diphtheria and tetanus toxoids, acellular pertussis (DTaP) vaccine at 2 months of chronological age", "options": {"A": "Give first dose of hepatitis B vaccine at 3 months of chronological age", "B": "Give first dose of influenza vaccine at 2 months of chronological age", "C": "Give first dose of varicella vaccine at 2 months of chronological age", "D": "Give first dose of Haemophilus influenza type b vaccine at 3 months of chronological age", "E": "Give first dose of diphtheria and tetanus toxoids, acellular pertussis (DTaP) vaccine at 2 months of chronological age"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "One day after undergoing a right hemicolectomy for colon cancer, a 55-year-old woman has back pain and numbness and difficulty moving her legs. Her initial postoperative course was uncomplicated. Current medications include prophylactic subcutaneous heparin. Her temperature is 37.2°C (98.9°F), pulse is 100/min, respirations are 18/min, and blood pressure is 130/90 mm Hg. Examination shows a well-positioned epidural catheter site without redness or swelling. There is weakness of the lower extremities. Deep tendon reflexes are absent in both lower extremities. Perineal sensation to pinprick is decreased. Her hemoglobin concentration is 11.2 g/dL, leukocyte count is 6,000/m3, and platelet count is 215,000/mm3. Her erythrocyte sedimentation rate is 19 mm/h. A T2-weighted MRI of the spine shows a 15-cm, hyperintense, epidural space-occupying lesion compressing the spinal cord at the level of L2–L5 vertebrae. Which of the following is the most appropriate next step in treatment?", "answer": "Perform surgical decompression", "options": {"A": "Observation", "B": "Perform surgical decompression", "C": "Perform CT-guided aspiration", "D": "Obtain lumbar puncture", "E": "Obtain blood cultures\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-month-old boy is brought to the physician by his mother because of a 2-day history of rhinorrhea, nasal congestion, and cough. He has been feeding normally and has not had vomiting or diarrhea. The infant was born at term via uncomplicated spontaneous vaginal delivery. Immunizations are up-to-date. Eight months ago, he was treated for a urinary tract infection. Four months ago, he had an uncomplicated upper respiratory infection. He is alert and well-appearing. His temperature is 38.4°C (101.1°F), pulse is 110/min, respirations are 32/min, and blood pressure is 90/56 mm Hg. Examination shows erythematous nasal mucosa. Scattered expiratory wheezing is heard throughout both lung fields. The remainder of the examination shows no abnormalities. An x-ray of the chest is shown. After administration of an antipyretic, which of the following is the most appropriate next step in management?", "answer": "Provide reassurance", "options": {"A": "Provide reassurance", "B": "Begin oral antibiotic therapy", "C": "Perform PPD skin testing", "D": "Obtain a thoracic CT scan", "E": "Measure T cell count"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 73-year-old man presents to his primary care physician with chest pain. He noticed the pain after walking several blocks, and the pain is relieved by sitting. On exam, he has a BP 155/89 mmHg, HR 79 bpm, and T 98.9 F. The physician refers the patient to a cardiologist and offers prescriptions for carvedilol and nitroglycerin. Which of the following describes the mechanism or effects of each of these medications, respectively?", "answer": "Decreased cAMP; Increased cGMP", "options": {"A": "Increased cAMP; Increased cAMP", "B": "Increased contractility; Decreased endothelial nitrous oxide", "C": "Decreased cAMP; Increased cGMP", "D": "Decreased cGMP; Increased venous resistance", "E": "Increased heart rate; Decreased arterial resistance"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 84-year-old man comes to the emergency department because of lower back pain and lower extremity weakness for 3 weeks. Over the past week, he has also found it increasingly difficult to urinate. He has a history of prostate cancer, for which he underwent radical prostatectomy 8 years ago. His prostate-specific antigen (PSA) level was undetectable until a routine follow-up visit last year, when it began to increase from 0.8 ng/mL to its present value of 64.3 ng/mL (N < 4). An MRI of the spine shows infiltrative vertebral lesions with a collapse of the L5 vertebral body, resulting in cord compression at L4–L5. The patient receives one dose of intravenous dexamethasone and subsequently undergoes external beam radiation. Which of the following cellular changes is most likely to occur as a result of this treatment?", "answer": "Generation of hydroxyl radicals", "options": {"A": "Formation of pyrimidine dimers", "B": "Disruption of microtubule assembly", "C": "Intercalation of neighbouring DNA base pairs", "D": "Generation of hydroxyl radicals", "E": "Formation of DNA crosslinks"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old man presents to the emergency department with severe anxiety. He has had multiple episodes in the past treated with low dose lorazepam. The patient states that he feels as if he is going to die and that he cannot breathe. His past medical history is notable for depression and anxiety. His temperature is 98.1°F (36.7°C), blood pressure is 122/83 mmHg, pulse is 153/min, respirations are 13/min, and oxygen saturation is 98% on room air. The patient is given a low dose of lorazepam and reports a complete resolution of his symptoms. An ECG is performed and demonstrates prolongation of the P-R interval with a widened QRS complex. There is a P wave preceding every QRS complex, no dropped QRS complexes, and the P-R interval does not change. His initial lab values are unremarkable. Which of the following is the best management of this patient?", "answer": "Electrophysiological studies", "options": {"A": "Cardiac catheterization", "B": "Electrophysiological studies", "C": "No further management needed", "D": "Sodium bicarbonate", "E": "Transcutaneous pacing"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 74-year-old male presents to his primary care physician complaining of left lower back pain. He reports a four-month history of worsening left flank pain. More recently, he has started to notice that his urine appears brown. His past medical history is notable for gout, hypertension, hyperlipidemia, and myocardial infarction status-post stent placement. He has a 45 pack-year smoking history and drinks 2-3 alcoholic beverages per day. His temperature is 100.9°F (38.3°C), blood pressure is 145/80 mmHg, pulse is 105/min, and respirations are 20/min. Physical examination is notable for left costovertebral angle tenderness. A CT of this patient’s abdomen is shown in figure A. This lesion most likely arose from which of the following cells?", "answer": "Proximal tubule cells", "options": {"A": "Proximal tubule cells", "B": "Distal convoluted tubule cells", "C": "Mesangial cells", "D": "Perirenal adipocytes", "E": "Collecting duct epithelial cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old man is brought to the emergency department by his wife for high blood pressure readings at home. He is asymptomatic. He has a history of hypertension and hyperlipidemia for which he takes atenolol and atorvastatin, however, his wife reports that he recently ran out of atenolol and has not been able to refill it due to lack of health insurance. His temperature is 36.8°C (98.2°F), the pulse 65/min, the respiratory rate 22/min, and the blood pressure 201/139 mm Hg. He has no papilledema on fundoscopic examination. A CT scan shows no evidence of intracranial hemorrhage or ischemia. Of the following, what is the next best step?", "answer": "Start or restart low-dose medication to reduce blood pressure gradually over the next 24–48 hours", "options": {"A": "Start or restart low-dose medication to reduce blood pressure gradually over the next 24–48 hours", "B": "Start or restart low-dose medication to reduce blood pressure aggressively over the next 24–48 hours", "C": "Start high-dose medication to bring his blood pressure to under 140/90 within 24 hours", "D": "Admit him to the ICU and start intravenous medication to reduce blood pressure by 10% in the first hour", "E": "Admit him to the ICU and start intravenous medication to reduce blood pressure by 25% in the first 4 hours"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old woman is in a high-speed motor vehicle accident and suffers multiple injuries to her extremities and abdomen. In the field, she was bleeding profusely bleeding and, upon arrival to the emergency department, she is lethargic and unable to speak. Her blood pressure on presentation is 70/40 mmHg. The trauma surgery team recommends emergency exploratory laparotomy. While the patient is in the trauma bay, her husband calls and says that the patient is a Jehovah's witness and that her religion does not permit her to receive a blood transfusion. No advanced directives are available. Which of the following is an appropriate next step?", "answer": "Provide transfusions as needed", "options": {"A": "Provide transfusions as needed", "B": "Ask husband to bring identification to the trauma bay", "C": "Withhold transfusion based on husband's request", "D": "Obtain an ethics consult", "E": "Obtain a court order for transfusion"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old woman presents to her primary care physician for evaluation of malaise, joint pains, and rash. She has developed joint pain in her hands over the last month, and has noted a rash over her face that gets worse with sun exposure. She is taking no medication at the present time. On further physical examination, an erythematous rash with a small amount of underlying edema is seen on her face. Her complete blood count is remarkable due to a lymphocytopenia. What are other disorders known to cause lymphocytopenia?\nI 22q.11.2 deletion syndrome\nII Bruton tyrosine kinase (BTK) defect\nIII Diphyllobothrium latum infection\nIV Whole body radiation\nV Glanzmann-Riniker syndrome", "answer": "I, II, IV, V", "options": {"A": "I, II, III", "B": "I, III, V", "C": "III, IV", "D": "I, II, IV, V", "E": "III, V"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old woman comes to the physician for a follow-up examination. She has a history of Crohn disease, for which she takes methotrexate. She and her husband would like to start trying to have a child. Because of the teratogenicity of methotrexate, the physician switches the patient from methotrexate to a purine analog drug that inhibits lymphocyte proliferation by blocking nucleotide synthesis. Toxicity of the newly prescribed purine analog would most likely increase if the patient was also being treated with which of the following medications?", "answer": "Febuxostat", "options": {"A": "Febuxostat", "B": "Pemetrexed", "C": "Rasburicase", "D": "Hydroxyurea", "E": "Cyclosporine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Antituberculosis treatment is started. Two months later, the patient comes to the physician for a follow-up examination. The patient feels well. She reports that she has had tingling and bilateral numbness of her feet for the past 6 days. Her vital signs are within normal limits. Her lips are dry, scaly, and slightly swollen. Neurologic examination shows decreased sensation to pinprick and light touch over her feet, ankles, and the distal portion of her calves. Laboratory studies show:\nLeukocyte count 7400 /mm3\nRBC count 2.9 million/mm3\nHemoglobin 10.8 g/dL\nHematocrit 30.1%\nMean corpuscular volume 78 fL\nMean corpuscular hemoglobin 24.2 pg/cell\nPlatelet count 320,000/mm3\nSerum\nGlucose 98 mg/dL\nAlanine aminotransferase (ALT) 44 U/L\nAspartate aminotransferase (AST) 52 U/L\nAdministration of which of the following is most likely to have prevented this patient's neurological symptoms?\"", "answer": "Pyridoxine", "options": {"A": "Vitamin B12", "B": "Vitamin E", "C": "Pyridoxine", "D": "Iron", "E": "Interferon beta\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Before starting a new job at a law firm, a 33-year-old woman speaks to a representative about the health insurance plan offered by the firm. The representative explains that treatment is provided by primary health care physicians who focus on preventive care. Patients require a referral by the primary care physician for specialist care inside the network; treatment by health care providers outside the network is only covered in the case of an emergency. When the prospective employee asks how prices are negotiated between the health insurance company and the health care providers, the physician explains that the health care providers get a fixed payment for each patient enrolled over a specific period of time, regardless of whether or not services are provided. This arrangement best describes which of the following health care payment models?", "answer": "Capitation", "options": {"A": "Per diem payment", "B": "Bundled payment", "C": "Fee-for-service", "D": "Discounted fee-for-service", "E": "Capitation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 73-year-old man with a 50-year history of type 2 diabetes and stage 3 chronic kidney disease presents to his primary care doctor for a scheduled follow-up and routine labs. He states that he has had no real change in his health except that he feels like he has had bouts of lightheadedness and almost passing out, which resolve with sitting down. The patient does not have a history of syncope or arrhythmia. On his labs, he is found to have a hemoglobin of 11.0 g/dL. His estimated glomerular filtration rate is determined to be 45 ml/min/1.73m^2. Testing of his stool is negative for blood. Additionally, a peripheral blood smear demonstrates normochromic cells. As a result, the patient is started on erythropoietin. Which of the following likely describes the anemia?", "answer": "Normocytic anemia with decreased reticulocyte count", "options": {"A": "Macrocytic anemia with megaloblasts", "B": "Macrocytic anemia without megaloblasts", "C": "Microcytic anemia", "D": "Normocytic anemia with decreased reticulocyte count", "E": "Normocytic anemia with increased reticulocyte count"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old man presents to the physician with severe lower back pain and fatigue for 3 months. The pain increases with activity. He has no history of a serious illness. He takes ibuprofen for pain relief. He does not smoke. The blood pressure is 105/65 mm Hg, the pulse is 86/min, the respirations are 16/min, and the temperature is 36.7℃ (98.1℉). The conjunctivae are pale. Palpation over the 1st lumbar vertebra shows tenderness. The heart, lung, and abdominal examination shows no abnormalities. No lymphadenopathy is palpated. The results of the laboratory studies show:\nLaboratory test\nHemoglobin 9 g/dL\nMean corpuscular volume 90 μm3\nLeukocyte count 5,500/mm3 with a normal differential\nPlatelet count 350,000/mm3\nSerum\nCalcium 11.5 mg/dL\nAlbumin 3.8 g/dL\nUrea nitrogen 54 mg/dL\nCreatinine 2.5 mg/dL\nLumbosacral computed tomography (CT) scan shows a low-density lesion in the 1st lumbar vertebra and several similar lesions in the pelvic bones. Which of the following is the most likely diagnosis?", "answer": "Multiple myeloma", "options": {"A": "Metastatic prostatic cancer", "B": "Multiple myeloma", "C": "Secondary hyperparathyroidism", "D": "Small-cell lung carcinoma", "E": "Waldenstrom’s macroglobulinemia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old man visits his physician complaining of hematochezia over the last several days. He also has tenesmus and bowel urgency without any abdominal pain. He has had several milder episodes over the past several years that resolved on their own. He has no history of a serious illness and takes no medications. His blood pressure is 129/85 mm Hg; temperature, 37.4°C (99.3°F); and pulse, 75/min. On physical exam, his abdominal examination shows mild tenderness on deep palpation of the left lower quadrant. Digital rectal examination reveals anal tenderness and fresh blood. Stool examination is negative for pathogenic bacteria and an ova and parasite test is negative. Erythrocyte sedimentation rate is 28 mm/h. Colonoscopy shows diffuse erythema involving the rectum and extending to the distal sigmoid. The mucosa also shows a decreased vascular pattern with fine granularity. The remaining colon and distal ileum are normal. Biopsy of the inflamed mucosa of the sigmoid colon shows distorted crypt architecture. The most appropriate next step is to administer which of the following?", "answer": "Mesalamine", "options": {"A": "Azathioprine", "B": "Ciprofloxacin", "C": "Mesalamine", "D": "Metronidazole", "E": "Total parenteral nutrition"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old girl is brought to the physician for a well-child examination. She has been healthy apart from an episode of bronchiolitis as an infant. Her 6-year-old sister recently underwent surgery for ventricular septal defect closure. She is at the 60th percentile for height and weight. Her mother is concerned about the possibility of the patient having a cardiovascular anomaly. Which of the following is most likely to indicate a benign heart murmur in this child?", "answer": "A grade 2/6 continuous murmur heard at the right supraclavicular region", "options": {"A": "A grade 3/6 systolic ejection murmur heard along the left lower sternal border that increases on valsalva", "B": "A grade 4/6 midsystolic murmur at the right upper sternal border that increases on rapid squatting", "C": "A grade 2/6 continuous murmur heard at the right supraclavicular region", "D": "A grade 4/6 holosytolic murmur heard along the left lower sternal border that increases on hand grip", "E": "A grade 3/6 holosytolic murmur at the apex that increases on hand grip"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A mother with HIV has given birth to a healthy boy 2 days ago. She takes her antiretroviral medication regularly and is compliant with the therapy. Before being discharged, her doctor explains that she cannot breastfeed the child since there is a risk of infection through breastfeeding and stresses that the child can benefit from formula feeding. The physician stresses the importance of not overheating the formula since Vitamin C may be inactivated by overheating. Which process could be impaired if the mother boiled the formula longer than needed?", "answer": "Collagen synthesis", "options": {"A": "Heme synthesis", "B": "Purine synthesis", "C": "Collagen synthesis", "D": "Protein catabolism", "E": "Fatty acid metabolism"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A healthy 33-year-old gravida 1, para 0, at 15 weeks' gestation comes to the genetic counselor for a follow-up visit. Her uncle had recurrent pulmonary infections, chronic diarrhea, and infertility, and died at the age of 28 years. She does not smoke or drink alcohol. The results of an amniotic karyotype analysis show a deletion of Phe508 on chromosome 7. This patient's fetus is at greatest risk for developing which of the following complications?", "answer": "Meconium ileus", "options": {"A": "Duodenal atresia", "B": "Congenital megacolon", "C": "Cardiac defects", "D": "Meconium ileus", "E": "Neural tube defects"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Four days after being admitted to the intensive care unit for acute substernal chest pain and dyspnea, an 80-year-old man is evaluated for hypotension. Coronary angiography on admission showed an occlusion in the left anterior descending artery, and a drug-eluting stent was placed successfully. The patient has a history of hypertension and type 2 diabetes mellitus. Current medications include aspirin, clopidogrel, metoprolol, lisinopril, and atorvastatin. His temperature is 37.2 °C (99 °F), pulse is 112/min, respirations are 21/min, and blood pressure is 72/50 mm Hg. Cardiac examination shows a normal S1 and S2 and a new harsh, holosystolic murmur heard best at the left sternal border. There is jugular venous distention and a right parasternal heave. The lungs are clear to auscultation. Pitting edema extends up to the knees bilaterally. An ECG shows Q waves in the inferior leads. Which of the following is the most likely cause of this patient’s hypotension?", "answer": "Interventricular septum rupture", "options": {"A": "Ascending aortic dissection rupture", "B": "Post-infarction fibrinous pericarditis", "C": "Left ventricular free wall rupture", "D": "Left ventricular aneurysm rupture", "E": "Interventricular septum rupture"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 68-year-old right hand-dominant man presents to the emergency room complaining of severe right arm pain after falling down a flight of stairs. He landed on his shoulder and developed immediate severe upper arm pain. Physical examination reveals a 2-cm laceration in the patient’s anterior right upper arm. Bone is visible through the laceration. An arm radiograph demonstrates a displaced comminuted fracture of the surgical neck of the humerus. Irrigation and debridement is performed immediately and the patient is scheduled to undergo definitive operative management of his fracture. In the operating room on the following day, the operation is more complicated than expected and the surgeon accidentally nicks a neurovascular structure piercing the coracobrachialis muscle. This patient would most likely develop a defect in which of the following?", "answer": "Lateral forearm skin sensation", "options": {"A": "Elbow extension", "B": "Forearm pronation", "C": "Lateral forearm skin sensation", "D": "Medial arm skin sensation", "E": "Wrist extension"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A first-year medical student is conducting a summer project with his medical school's pediatrics department using adolescent IQ data from a database of 1,252 patients. He observes that the mean IQ of the dataset is 100. The standard deviation was calculated to be 10. Assuming that the values are normally distributed, approximately 87% of the measurements will fall in between which of the following limits?", "answer": "85–115", "options": {"A": "70–130", "B": "65–135", "C": "85–115", "D": "80–120", "E": "95–105\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "The the mean, median, and mode weight of 37 newborns in a hospital nursery is 7 lbs 2 oz. In fact, there are 7 infants in the nursery that weigh exactly 7 lbs 2 oz. The standard deviation of the weights is 2 oz. The weights follow a normal distribution. A newborn delivered at 10 lbs 2 oz is added to the data set. What is most likely to happen to the mean, median, and mode with the addition of this new data point?", "answer": "The mean will increase; the median will stay the same; the mode will stay the same", "options": {"A": "The mean will increase; the median will increase; the mode will increase", "B": "The mean will stay the same; the median will increase; the mode will increase", "C": "The mean will stay the same; the median will increase; the mode will stay the same", "D": "The mean will increase; the median will stay the same; the mode will stay the same", "E": "The mean will increase; the median will increase; the mode will stay the same"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 10-month-old boy is brought to the emergency department by his parents because he has a high fever and severe cough. His fever started 2 days ago and his parents are concerned as he is now listless and fatigued. He had a similar presentation 5 months ago and was diagnosed with pneumonia caused by Staphyloccocus aureus. He has been experiencing intermittent diarrhea and skin abscesses since birth. The child had an uneventful birth and the child is otherwise developmentally normal. Analysis of this patient's sputum reveals acute angle branching fungi and a throat swab reveals a white plaque with germ tube forming yeast. Which of the following is most likely to be abnormal in this patient?", "answer": "NADPH oxidase activity", "options": {"A": "Autoimmune regulator function", "B": "LFA-1 integrin binding", "C": "Lysosomal trafficking", "D": "NADPH oxidase activity", "E": "Thymus development"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 46-year-old woman comes to the physician for a routine health examination. She was last seen by a physician 3 years ago. She has been healthy aside from occasional mild flank pain. Her only medication is a multivitamin. Her blood pressure is 154/90 mm Hg. Physical examination shows no abnormalities. Serum studies show:\nSodium 141 mEq/L\nPotassium 3.7 mEq/L\nCalcium 11.3 mg/dL\nPhosphorus 2.3 mg/dL\nUrea nitrogen 15 mg/dL\nCreatinine 0.9 mg/dL\nAlbumin 3.6 g/dL\nSubsequent serum studies show a repeat calcium of 11.2 mg/dL, parathyroid hormone concentration of 890 pg/mL, and 25-hydroxyvitamin D of 48 ng/mL (N = 25–80). Her 24-hour urine calcium excretion is elevated. An abdominal ultrasound shows several small calculi in bilateral kidneys. Further testing shows normal bone mineral density. Which of the following is the most appropriate next step in management?\"", "answer": "Refer to surgery for parathyroidectomy", "options": {"A": "Refer to surgery for parathyroidectomy", "B": "Begin cinacalcet therapy", "C": "Order serum protein electrophoresis", "D": "Begin hydrochlorothiazide therapy", "E": "Perform percutaneous nephrolithotomy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 12-year-old boy is brought in by his mother to the emergency department. He has had abdominal pain, fever, nausea, vomiting, and loss of appetite since yesterday. At first, the mother believed it was just a \"stomach flu,\" but she is growing concerned about his progressive decline. Vitals include: T 102.3 F, HR 110 bpm, BP 120/89 mmHg, RR 16, O2 Sat 100%. Abdominal exam is notable for pain over the right lower quadrant. What is the next best step in management in addition to IV hydration and analgesia?", "answer": "Right lower quadrant ultrasound", "options": {"A": "Abdominal CT scan with IV and PO contrast", "B": "Abdominal CT scan with IV contrast", "C": "Upright and supine abdominal radiographs", "D": "Right lower quadrant ultrasound", "E": "Abdominal MRI with gadolinium contrast"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old man with a long history of mild persistent asthma on daily fluticasone therapy has been using his albuterol inhaler every day for the past month and presents requesting a refill. He denies any recent upper respiratory infections, but he says he has felt much more short of breath throughout this time frame. He works as a landscaper, and he informs you that he has been taking longer to complete some of his daily activities on the job. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. His physical exam reveals mild bilateral wheezes and normal heart sounds. What changes should be made to his current regimen?", "answer": "Add salmeterol to current regimen", "options": {"A": "Add ciclesonide to current regimen", "B": "Add salmeterol to current regimen", "C": "Discontinue fluticasone and instead use salmeterol", "D": "Add cromolyn to current regimen", "E": "Discontinue fluticasone and add ipratropium to current regimen"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3500-g (7 lb 11 oz) healthy female newborn is delivered at 38 weeks' gestation. Chorionic villus sampling (CVS) in the first trimester showed a trisomy of chromosome 21 but the pregnancy was otherwise uncomplicated. Physical examination of the newborn is normal. Chromosomal analysis at birth shows a 46, XX karyotype. Which of the following is the most likely explanation for the prenatal chromosomal abnormality?", "answer": "Placental mosaicism", "options": {"A": "Maternal disomy", "B": "Phenotypic pleiotropy", "C": "Incomplete penetrance", "D": "Variable expressivity", "E": "Placental mosaicism"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 11-year-old girl presents with a 1-day history of frothy brown urine. She has no significant medical history and takes no medications. She reports that several of her classmates have been sick, and she notes that she had a very sore throat with a fever approx. 2 weeks ago. Her blood pressure is 146/94 mm Hg, heart rate is 74/min, and respiratory rate is 14/min. Laboratory analysis reveals elevated serum creatinine, hematuria with RBC casts, and elevated urine protein without frank proteinuria. Physical examination reveals a healthy-looking girl with no abdominal or costovertebral angle tenderness. Which of the following is the most likely diagnosis?", "answer": "Poststreptococcal glomerulonephritis", "options": {"A": "Alport syndrome", "B": "Minimal change disease", "C": "Membranoproliferative glomerulonephritis", "D": "Poststreptococcal glomerulonephritis", "E": "Henoch-Schönlein purpura"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old male adolescent presents to his pediatrician with increasing fatigue and breathlessness with exercise. His parents inform the doctor that they have recently migrated from a developing country, where he was diagnosed as having a large ventricular septal defect (VSD). However, due to their poor economic condition and scarce medical facilities, surgical repair was not performed in that country. The pediatrician explains to the parents that patients with large VSDs are at increased risk for several complications, including Eisenmenger syndrome. If the patient has developed this complication, he is not a good candidate for surgical closure of the defect. Which of the following clinical signs, if present on physical examination, would suggest the presence of this complication?", "answer": "Right ventricular heave", "options": {"A": "A loud first heart sound", "B": "A mid-diastolic low-pitched rumble at the apex", "C": "Right ventricular heave", "D": "Prominence of the left precordium", "E": "Lateral displacement of the apical impulse"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 59-year-old man presents to the emergency department with right-sided weakness and an inability to speak for the past 2 hours. His wife says he was gardening in his backyard when he suddenly lost balance and fell down. The patient has a past medical history of hypertension, diabetes mellitus, and coronary artery disease. Two years ago, he was admitted to the coronary intensive care unit with an anterolateral myocardial infarction. He has not been compliant with his medications since he was discharged. On physical examination, his blood pressure is 110/70 mm Hg, pulse is 110/min and irregular, temperature is 36.6°C (97.8°F), and respiratory rate is 18/min. Strength is 2/5 in both his right upper and right lower extremities. His right calf is edematous with visible varicose veins. Which of the following is the best method to detect the source of this patient’s stroke?", "answer": "ECG", "options": {"A": "Duplex ultrasound of his right leg", "B": "Carotid duplex", "C": "Head CT without contrast", "D": "ECG", "E": "V/Q scan of his lungs"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old boy is brought to the emergency department because of worsening pain and swelling in both of his hands for 1 week. He appears distressed. His temperature is 38.5°C (101.4°F). Examination shows erythema, swelling, warmth, and tenderness on the dorsum of his hands. His hemoglobin concentration is 9.1 g/dL. A peripheral blood smear is shown. The drug indicated to prevent recurrence of this patient's symptoms is also used to treat which of the following conditions?", "answer": "Polycythemia vera", "options": {"A": "Primary syphilis", "B": "Chronic kidney disease", "C": "Megaloblastic anemia", "D": "Iron intoxication", "E": "Polycythemia vera"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 30-year-old primigravid woman at 14 weeks' gestation comes to the physician for her first prenatal visit. She reports some nausea and fatigue. She takes lithium for bipolar disorder and completed a course of clindamycin for bacterial vaginosis 12 weeks ago. She works as a teacher at a local school. She smoked a pack of cigarettes daily for 12 years but stopped after finding out that she was pregnant. She does not drink alcohol. Her temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 125/80 mm Hg. Pelvic examination shows a uterus consistent in size with a 14-week gestation. There is mild lower extremity edema bilaterally. Urinalysis is within normal limits. The patient's child is at increased risk for developing which of the following complications?", "answer": "Atrialized right ventricle", "options": {"A": "Ototoxicity and hearing loss", "B": "Atrialized right ventricle", "C": "Fetal hydantoin syndrome", "D": "Bone damage", "E": "Chorioretinitis\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old woman with COPD comes to the emergency department with 2-day history of worsening shortness of breath and cough. She often has a mild productive cough, but she noticed that her sputum is more yellow than usual. She has not had any recent fevers, chills, sore throat, or a runny nose. Her only medication is a salmeterol inhaler that she uses twice daily. Her temperature is 36.7°C (98°F), pulse is 104/min, blood pressure is 134/73 mm Hg, respiratory rate is 22/min, and oxygen saturation is 85%. She appears uncomfortable and shows labored breathing. Lung auscultation reveals coarse bibasilar inspiratory crackles. A plain film of the chest shows mild hyperinflation and flattening of the diaphragm but no consolidation. She is started on supplemental oxygen via nasal cannula. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Prednisone and albuterol", "options": {"A": "Roflumilast and prednisone", "B": "Albuterol and montelukast", "C": "Prednisone and salmeterol", "D": "Albuterol and theophylline", "E": "Prednisone and albuterol"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old woman comes to the emergency department because of weakness and fatigue for 2 days. She has also noticed that her urine is darker than usual. For the past week, she has had a persistent non-productive cough and low-grade fever. She has seasonal allergies. She drinks one to two glasses of wine on social occasions and does not smoke. Her temperature is 37.9°C (100.2°F), pulse is 88/min, respirations are 18/min, and blood pressure is 110/76 mm Hg. She has conjunctival pallor and scleral icterus. Cardiopulmonary examination shows bibasilar crackles. The remainder of the physical examination shows no abnormalities. Laboratory studies show:\nLeukocyte count 8,000/mm3\nHemoglobin 7.1 g/dL\nHematocrit 21%\nPlatelet count 110,000/mm3\nMCV 94 μm3\nSerum\nTotal bilirubin 4.3 mg/dL\nDirect 1.1 mg/dL\nIndirect 3.2 mg/dL\nAST 15 U/L\nALT 17 U/L\nLDH 1,251 U/L\nHaptoglobin 5.8 mg/dL (N = 41–165)\nAn x-ray of the chest shows bilateral patchy infiltrates. A peripheral blood smear shows spherocytes. Which of the following is most likely to confirm the diagnosis?\"", "answer": "Direct Coombs test", "options": {"A": "Osmotic fragility test", "B": "Direct Coombs test", "C": "ADAMTS13 activity and inhibitor profile", "D": "Hemoglobin electrophoresis", "E": "Flow cytometry"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 46-year-old woman comes to the physician for a follow-up examination. She had a blood pressure recording of 148/94 mm Hg on her previous visit one week ago. Her home blood pressure log shows readings of 151/97 and 146/92 mm Hg in the past week. She has no history of serious illness and takes no medications. She is 160 cm (5 ft 3 in) tall and weighs 52 kg (115 lb); BMI is 20 kg/m2. Her pulse is 88/min and blood pressure is 150/96 mm Hg. Cardiopulmonary examination is unremarkable. Abdominal examination shows no abnormalities. The extremities are well perfused with strong peripheral pulses. Serum concentrations of electrolytes, creatinine, lipids, TSH, and fasting glucose are within the reference range. A urinalysis is within normal limits. Which of the following is the most appropriate next step in management?", "answer": "Electrocardiogram", "options": {"A": "Electrocardiogram", "B": "Plasma renin activity", "C": "Polysomnography", "D": "Echocardiography", "E": "Renal ultrasonography"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A sample is taken of an ulcer in the inguinal region of a 29-year-old Malaysian male who has had unprotected sex in the past few months. Intracytoplasmic inclusions are seen in the Giemsa staining in Image A. On which of the following can the organism in the staining be grown?", "answer": "Yolk sac of a chick embryo", "options": {"A": "Bordet-Gengou agar", "B": "Löwenstein-Jensen agar", "C": "Charcoal yeast extract agar with cysteine and iron", "D": "Eaton's agar", "E": "Yolk sac of a chick embryo"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old man who recently emigrated from Colombia comes to the physician because of a 3-month history of shortness of breath and fatigue. Physical examination shows jugular venous distention and an additional late diastolic heart sound. Crackles are heard at the lung bases bilaterally. Cardiac catheterization is performed and left ventricular pressures are obtained. The left ventricular pressure-volume relationship compared to that of a healthy patient is shown. Which of the following is the most likely cause of this patient's heart failure?", "answer": "Cardiac sarcoidosis", "options": {"A": "Chagas heart disease", "B": "Viral myocarditis", "C": "Cardiac sarcoidosis", "D": "Alcohol use disorder", "E": "Thiamine deficiency"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old female college basketball player presents in Sports Clinic after she felt a \"pop\" in her knee after coming down with a rebound. To examine the patient, you have her lie down on the table with her knees flexed 90 degrees. With your hand around her knee you are able to draw the tibia toward you from underneath the femur. The torn structure implicated by this physical exam maneuver has which of the following attachments?", "answer": "The anterior intercondylar area of tibia and the posteromedial aspect of the lateral femur", "options": {"A": "The posterior intercondylar area of tibia and the posteromedial aspect of the lateral femur", "B": "The anterior intercondylar area of tibia and the posteromedial aspect of the lateral femur", "C": "The patella and tibial tuberosity", "D": "The lateral epicondyle of the femur and the head of fibula", "E": "The medial condyle of the femur and the medial condyle of the tibia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old man is brought to the emergency department after having a seizure. His wife states that the patient has been struggling with alcohol abuse and has recently decided to \"quit once and for all\". Physical exam is notable for a malnourished patient responsive to verbal stimuli. He has moderate extremity weakness, occasional palpitations, and brisk deep tendon reflexes (DTRs). EKG demonstrates normal sinus rhythm and a prolonged QT interval. What nutritional deficiency most likely contributed to these findings?", "answer": "Magnesium", "options": {"A": "Potassium", "B": "Calcium", "C": "Folate", "D": "Magnesium", "E": "Vitamin D"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old man presents to his physician with a chronic cough which he has had for the last five years. He mentions that his cough is usually productive; however, sometimes it is dry. His past medical records show seven episodes of sinusitis over the last two years and two episodes of community acquired pneumonia. He is a non-smoker and there is no history of long-term exposure to passive smoking or other airway irritants. There is no family history of an allergic disorder. On physical examination, his vital signs are stable. General examination shows mild clubbing of his fingers and examination of his nasal turbinates reveals nasal polyps. Auscultation of his chest reveals crackles and scattered wheezing bilaterally. A high-resolution computed tomography (HRCT) of the chest shows dilated, “tram track” bronchi, predominantly involving upper lung fields. Which of the following is the next best step in the diagnostic evaluation of the patient?", "answer": "Measurement of sweat chloride levels", "options": {"A": "Sputum culture for acid-fast bacilli", "B": "Serum quantitative immunoglobulin levels", "C": "Measurement of sweat chloride levels", "D": "Skin testing for Aspergillus reactivity", "E": "Testing for swallowing function"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 64-year-old male with a past medical history of obesity, diabetes, hypertension, and hyperlipidemia presents with an acute onset of nausea, vomiting, diaphoresis, and crushing substernal chest pain. Vital signs are temperature 37° C, HR 110, BP 149/87, and RR of 22 with an oxygen saturation of 99% on room air. Physical exam reveals a fourth heart sound (S4), and labs are remarkable for an elevated troponin. EKG is shown below. The pathogenesis of the condition resulting in this patient’s presentation involves:", "answer": "A fully obstructive thrombus at the site of a ruptured, ulcerated atherosclerotic plaque", "options": {"A": "Genetic inheritance of a mutation in ß-myosin or troponin expressed in cardiac myocytes", "B": "A fully obstructive thrombus at the site of a ruptured, ulcerated atherosclerotic plaque", "C": "A partially occlusive thrombus at the site of a ruptured, ulcerated atherosclerotic plaque", "D": "Destruction of the vasa vasorum caused by vasculitic phenomena", "E": "A stable atheromatous lesion without overlying thrombus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old man is brought to the emergency room because of fever and increasing confusion for the past 2 days. He has paranoid schizophrenia and hypertension. His current medications are chlorpromazine and amlodipine. He appears ill. He is not oriented to time, place, or person. His temperature is 40°C (104°F), pulse is 130/min, respirations are 29/min and blood pressure is 155/100 mm Hg. Examination shows diaphoresis. Muscle tone is increased bilaterally. Deep tendon reflexes are 1+ bilaterally. Neurologic examination shows psychomotor agitation. His speech is incoherent. Lungs are clear to auscultation. His neck is supple. The abdomen is soft and nontender. Serum laboratory analysis shows a leukocyte count of 11,300/mm3 and serum creatine kinase concentration of 833 U/L. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Dantrolene", "options": {"A": "Dantrolene", "B": "Clozapine", "C": "Cyproheptadine", "D": "Physostigmine", "E": "Propranolol"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 67-year-old man comes to the emergency department because of decreased vision and black spots in front of his left eye for the past 24 hours. He states that it feels as if 'a curtain is hanging over his eye.' He sees flashes of light intermittently. He has no pain or diplopia. He underwent cataract surgery on the left eye 2 weeks ago. He has hypertension and type 2 diabetes mellitus. His sister has open-angle glaucoma. Current medications include metformin, linagliptin, ramipril, and hydrochlorothiazide. Vital signs are within normal limits. Examination shows a visual acuity in the right eye of 20/25 and the ability to count fingers at 3 feet in the left eye. The pupils are equal and reactive. The corneal reflex is present. The anterior chamber shows no abnormalities. The confrontation test is normal on the right side and shows nasal and inferior defects on the left side. Cardiopulmonary examination shows no abnormalities. The patient is awaiting dilation for fundus examination. Which of the following is the most likely diagnosis?", "answer": "Retinal detachment", "options": {"A": "Degenerative retinoschisis", "B": "Retinal detachment", "C": "Acute angle-closure glaucoma", "D": "Endophthalmitis", "E": "Hemorrhagic choroidal detachment"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old woman presents to her physician with the complaint of ringing in her right ear. She says it started about 3 months ago with associated progressive difficulty in hearing on the same side. Past medical history is significant for a hysterectomy 5 years ago due to dysfunctional uterine bleeding. She is currently not taking any medications. She is a non-smoker and drinks socially. On otoscopic examination, a red-blue pulsatile mass is observed behind the right tympanic membrane. A noncontrast CT scan of the head shows significant bone destruction resulting in a larger jugular foramen highly suggestive of a tumor derived from neural crest cells. Which of the cranial nerves are most likely to be involved in this type of lesion?", "answer": "Cranial nerves IX, X", "options": {"A": "Cranial nerves VII & VIII", "B": "Cranial nerves IX, X", "C": "Cranial nerves III, IV, VI", "D": "Cranial nerves I, II, V", "E": "Cranial nerves X, XI, XII"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy presents to a geneticist for generalized developmental delay. Upon presentation he is found to have a distinctive facial structure with prominent epicanthal folds and macroglossia. Further physical examination reveals a simian crease on his palms bilaterally. Based on these findings, the physician strongly suspects Down syndrome and obtains a karyotype. Surprisingly the karyotype shows 46 chromosomes with two normal appearing alleles of chromosome 21. Further examination with fluorescent probes reveals a third copy of chromosome 21 genes that have been incorporated into another chromosome. What is the name of this mechanism of Down syndrome inheritance?", "answer": "Robertsonian translocation", "options": {"A": "Nondisjunction", "B": "Mosaicism", "C": "Robertsonian translocation", "D": "Imprinting", "E": "Anticipation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-month-old infant male is brought to the emergency department with a 1-hour history of vomiting and convulsions. He was born at home and had sporadic prenatal care though his parents say that he appeared healthy at birth. He initially fed well; however, his parents have noticed that he has been feeding poorly and is very irritable since they moved on to baby foods. They have also noticed mild yellowing of his skin but assumed it would go away over time. On presentation, he is found to be very sleepy, and physical exam reveals an enlarged liver and spleen. The rest of the physical exam is normal. Which of the following enzymes is most likely functioning abnormally in this patient?", "answer": "Aldolase B", "options": {"A": "Aldolase B", "B": "Fructokinase", "C": "Gal-1-phosphate uridyl transferase", "D": "Galactokinase deficiency", "E": "Lactase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman is brought to the physician for the evaluation of fatigue for the past 6 months. During this period, she has had recurrent episodes of constipation and diarrhea. She also reports frequent nausea and palpitations. She works as a nurse at a local hospital. She has tried cognitive behavioral therapy, but her symptoms have not improved. Her mother has hypothyroidism. The patient is 170 cm (5 ft 7 in) tall and weighs 62 kg (137 lb); BMI is 21.5 kg/m2. She appears pale. Vital signs are within normal limits. Examination shows calluses on the knuckles and bilateral parotid gland enlargement. Oropharyngeal examination shows eroded dental enamel and decalcified teeth. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Administration of fluoxetine", "options": {"A": "Administration of fluoxetine", "B": "Administration of mirtazapine", "C": "Administration of olanzapine", "D": "Administration of venlafaxine", "E": "Administration of topiramate\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 50-year-old woman comes to the physician because of intermittent pain and numbness in her right hand for 6 weeks. She has a pins-and-needles sensation that worsens at night and is relieved when she shakes her hand. She also has episodic left knee pain throughout the day. She has a history of hypertension controlled with lisinopril. She takes over-the-counter medications for constipation. Her BMI is 35 kg/m2. Her mother has a history of rheumatoid arthritis. She looks fatigued. Her pulse is 57/min and blood pressure is 120/75 mm Hg. On physical examination, there is normal range of motion in the wrists and digits. Sensation is decreased to light touch in the thumb and index finger. There is no thenar muscle atrophy. Deep tendon reflexes are 1+ and there is mild edema in the legs. Which of the following treatments is most likely to benefit the patient?", "answer": "L-thyroxine", "options": {"A": "L-thyroxine", "B": "Methotrexate", "C": "Ibuprofen", "D": "Surgical decompression", "E": "Oral prednisone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 13-year-old female presents to the emergency room complaining of severe abdominal pain. She reports acute onset of diffuse abdominal pain twelve hours prior to presentation. She has vomited twice and has not had a bowel movement in that time. She is in the fetal position because it relieves the pain. Her past medical history is notable for asthma; however, she was adopted as a baby and her family history is unknown. Her temperature is 99.7°F (37.6°C), blood pressure is 130/85 mmHg, pulse is 110/min, and respirations are 22/min. Physical examination reveals abdominal distension and tenderness to palpation. A sausage-shaped abdominal mass is palpated in the right upper quadrant. Mucocutaneous blue-gray macules are evident on the child’s buccal mucosa. A mutation in which of the following genes is associated with this patient’s condition?", "answer": "STK11", "options": {"A": "C-KIT", "B": "NF1", "C": "TP53", "D": "APC", "E": "STK11"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old woman presents to her OB/GYN with complaints of missing her last 3 periods as well as intermittent spontaneous milky-white nipple discharge bilaterally for the past 3 months. Vital signs are stable and within normal limits. Neurologic examination is without abnormality, including normal visual fields. Serology and MRI of the brain are ordered, with results pending. Which of the following sets of laboratory results would be expected in this patient?", "answer": "Increased prolactin, decreased FSH, decreased LH", "options": {"A": "Decreased prolactin, decreased FSH, decreased LH", "B": "Decreased prolactin, increased FSH, increased LH", "C": "Increased prolactin, decreased FSH, increased LH", "D": "Increased prolactin, decreased FSH, decreased LH", "E": "Increased prolactin, increased FSH, increased LH"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old primigravid woman at 24 weeks' gestation comes to the physician for a prenatal visit. She feels well. She has no personal history of serious illness. Medications include iron supplements and a multivitamin. Her temperature is 37.2°C (99°F) and blood pressure is 108/60 mm Hg. Pelvic examination shows a uterus consistent in size with a 24-week gestation. A 1-hour 50-g glucose challenge shows a glucose concentration of 155 mg/dL (N < 135 mg/dL). A 100-g oral glucose tolerance test shows glucose concentrations of 205 mg/dL (N < 180 mg/dL) and 154 mg/dL (N <140 mg/dL) at 1 and 3 hours, respectively. She refuses treatment with insulin. Which of the following complications is her infant at greatest risk of developing at birth?", "answer": "Hypocalcemia", "options": {"A": "Hypocalcemia", "B": "Omphalocele", "C": "Intrauterine growth restriction", "D": "Hypermagnesemia", "E": "Hyperglycemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man walks into an urgent care clinic complaining of a headache and dizziness. Earlier today he was in his normal state of health when symptoms started and lasted about 20 minutes. He did not lose consciousness or actually vomit. He also mentions that he was sweating a lot at that time. He has had similar dizzy spells on three separate occasions. His past medical history is significant for a total thyroidectomy 10 years ago for carcinoma. He takes levothyroxine and a multivitamin every day. Several family members seem to suffer from similar spells. At the clinic, his blood pressure is 140/90 mm Hg, his heart rate is 120/min, his respiratory rate is 18/min, and his temperature is 36.6 °C (98.0 °F). On physical exam, he appears quite anxious and uncomfortable. His heart rate is tachycardic with normal rhythm and his lungs are clear to auscultation bilaterally. Small nodules are observed on his buccal mucosa and tongue. The patient is referred to an endocrinologist for further assessment and CT. On CT exam, a mass is observed involving the medulla of his right adrenal gland. Which of the following additional symptoms is associated with this patients condition?", "answer": "Pale skin", "options": {"A": "Bronchospasm", "B": "Decreased cardiac contractility", "C": "Pale skin", "D": "Bradycardia", "E": "Pupillary constriction"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old male with past history of hypertension, hyperlipidemia, and a 30 pack/year smoking history presents to his primary care physician for his annual physical. Because of his age and past smoking history, he is sent for screening abdominal ultrasound. He is found to have a 4 cm infrarenal abdominal aortic aneurysm. Surgical repair of his aneurysm is indicated if which of the following are present?", "answer": "Abdominal, back, or groin pain", "options": {"A": "Abdominal, back, or groin pain", "B": "Smoking history", "C": "Diameter >3 cm", "D": "Growth of < 0.5 cm in one year", "E": "Marfan's syndrome"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Twelve hours after undergoing a femoral artery embolectomy, an 84-year-old man is found unconscious on the floor by his hospital bed. He had received a patient-controlled analgesia pump after surgery. He underwent 2 coronary bypass surgeries, 2 and 6 years ago. He has coronary artery disease, hypertension, hypercholesterolemia, gastroesophageal reflux, and type 2 diabetes mellitus. His current medications include metoprolol, atorvastatin, lisinopril, sublingual nitrate, and insulin. He appears pale. His temperature is 36.1°C (97°F), pulse is 120/min, respirations are 24/min, and blood pressure 88/60 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 85%. The patient does not respond to commands and withdraws his extremities to pain. The pupils are constricted bilaterally. Examination shows cold, clammy skin and jugular venous distention. There is ecchymosis on the right temple and maxilla. There is a surgical incision over the right thigh that shows no erythema or discharge. Crackles are heard at both lung bases. A new grade 2/6 systolic murmur is heard at the apex. He is intubated and mechanically ventilated. Further evaluation of this patient is most likely to show which of the following?", "answer": "A new left bundle branch block on an ECG", "options": {"A": "Transudate within the pericardial layers", "B": "A new left bundle branch block on an ECG", "C": "Pulsatile abdominal mass at the level of the umbilicus", "D": "Positive procalcitonin and interleukin-6 levels", "E": "Improved mental status after naloxone administration\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 8-year-old boy is brought to the physician because of a 2-month history of headaches. He is at the 25th percentile for weight and 80th percentile for height. His vital signs are within normal limits. Physical examination shows no abnormalities. CT scan of the head shows a small suprasellar cystic mass compressing the infundibular stalk. Serum concentration of which of the following hormones is most likely to be increased in this patient?", "answer": "Prolactin", "options": {"A": "Luteinizing hormone", "B": "Somatotropin", "C": "Prolactin", "D": "Adrenocorticotropic hormone", "E": "Vasopressin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 39-year-old woman comes to the physician because of recurrent episodes of severe pain over her neck, back, and shoulders for the past year. The pain worsens with exercise and lack of sleep. Use of over-the-counter analgesics have not resolved her symptoms. She also has stiffness of the shoulders and knees and tingling in her upper extremities that is worse in the morning. She takes escitalopram for generalized anxiety disorder. She also has tension headaches several times a month. Her maternal uncle has ankylosing spondylitis. Examination shows marked tenderness over the posterior neck, bilateral mid trapezius, and medial aspect of the left knee. Muscle strength is normal. Laboratory studies, including a complete blood count, erythrocyte sedimentation rate, and thyroid-stimulating hormone are within the reference ranges. X-rays of her cervical and lumbar spine show no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Fibromyalgia", "options": {"A": "Polymyalgia rheumatica", "B": "Fibromyalgia", "C": "Axial spondyloarthritis", "D": "Polymyositis", "E": "Major depressive disorder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A cross-sectional study of 650 patients with confirmed bronchogenic carcinoma was conducted in patients of all age groups in order to establish a baseline picture for further mortality comparisons. All patients were investigated using thoracic ultrasound and computed tomography of the chest. Also, data about the size of the mass, invasion of lymph nodes and chest wall, pleural effusion, and eventual paralysis of the diaphragm were noted. The bias that can arise in this case, and that may hamper further conclusions on the aggressiveness and mortality of bronchogenic carcinoma, may be explained as a tendency to which of the following aspects?", "answer": "Uncover more indolent cases of the disease preferentially", "options": {"A": "Find more cases of the disease in older cohorts", "B": "Observe only the late stages of a disease with more severe manifestations", "C": "Detect only asymptomatic cases of the disease", "D": "Uncover more indolent cases of the disease preferentially", "E": "Identify more instances of fatal disease"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A randomized, controlled trial was undertaken by a team of clinical researchers to evaluate a new drug for the treatment of cluster headaches. This type of headache (that mostly affects men) is characterized by excruciating pain on 1 side of the head. After careful randomization and controlling for all of the known confounders, a total of 200 patients with cluster headaches were divided into 2 groups. The first group of study participants received 40 mg of the new drug, X, in the form of a powder mixed with water. The second group received 80 mg of verapamil (a calcium channel blocker that is commonly prescribed for cluster headaches) in the form of a labeled pill. Participants from both groups were mixed together in rooms designated for drug research purposes and could communicate freely. After the study period has finished without any loss to follow-up or skipped treatments, the outcome (pain alleviation) was assessed by trained researchers that were blinded to treatment assignment. Study results have shown that the new drug is more efficacious than current gold standard by both clinically and statistically significant margin. Therefore, the investigators concluded that this drug should be introduced for the treatment of cluster headaches. However, their conclusions are likely to be criticized on the grounds of which of the following?", "answer": "Response bias", "options": {"A": "Observer bias", "B": "Response bias", "C": "Convenience sampling bias", "D": "Attrition bias", "E": "Intention to treat bias"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 15-year-old girl is brought to the physician by her parents for lethargy, increased thirst, and urinary frequency for 10 days. She is 173 cm (5 ft 8 in) tall and weighs 54 kg (120 lb); BMI is 18 kg/m2. Physical examination shows no abnormalities. Her serum glucose concentration is 224 mg/dL. A urine dipstick is positive for ketone bodies. Which of the following is most likely involved in the pathogenesis of this patient's condition?", "answer": "T-cell infiltration of pancreatic islets", "options": {"A": "Expression of human leukocyte antigen subtype A3", "B": "B-cell production of antimitochondrial antibodies", "C": "Complement-mediated destruction of insulin receptors", "D": "T-cell infiltration of pancreatic islets", "E": "Pancreatic islet amyloid polypeptide deposition"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Last night you admitted a 72-year-old woman with severe COPD in respiratory distress. She is currently intubated and sedated and her family is at bedside. At the completion of morning rounds, the patient's adult son asks that you and the team take a minute to pray with him for his mother. What is the most appropriate response?", "answer": "\"I understand what you are experiencing and am happy to take a minute.\"", "options": {"A": "\"I'm sorry, but this is a public hospital, so we cannot allow any group prayers.\"", "B": "\"I understand what you are experiencing and am happy to take a minute.\"", "C": "\"I also believe in the power of prayer, so I will pray with you and insist that the rest of team joins us.\"", "D": "\"While I cannot offer you my prayers, I will work very hard to take care of your mother.\"", "E": "\"I don't feel comfortable praying for patients, but I will happily refer you to pastoral care.\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 32-year-old man comes to the physician because of a 2-month history of fatigue and daytime sleepiness. He works as an accountant and cannot concentrate at work anymore. He also has depressed mood and no longer takes pleasure in activities he used to enjoy, such as playing tennis with his friends. He has decreased appetite and has had a 4-kg (8.8-lb) weight loss of over the past 2 months. He does not have suicidal ideation. He is diagnosed with major depressive disorder and treatment with paroxetine is begun. The patient is at greatest risk for which of the following adverse effects?", "answer": "Decreased libido", "options": {"A": "Urinary retention", "B": "Increased suicidality", "C": "Decreased libido", "D": "Postural hypotension", "E": "Priapism"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 20-year-old woman is brought to the emergency department with a puncture wound on the right side of her chest. She was walking to her apartment when she was assaulted. As she resisted to give up her purse, the assailant stabbed her in the chest with a knife and ran away. She is in severe respiratory distress. Her heart rate is 140/min, respiratory rate is 28/min, and blood pressure is 145/65 mm Hg. The pulse oximetry shows an oxygen saturation of 84%. An oval puncture wound is seen on the right lateral aspect of her chest and she is stuporous. The heart sounds are normal and no jugular venous distension is seen. Distant breath sounds are present on the right. Which of the following changes during inspiration explains her breathing difficulty?", "answer": "Equal intrapleural and atmospheric pressures", "options": {"A": "Diminished inspiratory force due to pain", "B": "Decreased intrapleural pressure", "C": "Equal intrapleural and atmospheric pressures", "D": "Paralysis of the diaphragm", "E": "Increased elastic force of the chest wall pulling it inwards"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 54-year-old man electively underwent an open cholecystectomy for his cholelithiasis. The procedure was performed under general anesthesia with inhaled anesthetic agents after induction with an intravenous agent. The surgeon operated quickly, and the procedure was uncomplicated. As the surgery ended, the anesthesia resident stopped the anesthesia and noticed the oxygen saturation gradually decreasing to 84%. He quickly administers 100% oxygen and the hypoxia improves. Which of the following most likely accounts for the decreased oxygen saturation seen after the anesthesia was stopped in this patient?", "answer": "Diffusion hypoxia", "options": {"A": "Pneumothorax", "B": "Cardiotoxicity", "C": "Second gas effect", "D": "Laryngospasm", "E": "Diffusion hypoxia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old woman presents to clinic for routine checkup. She has no complaints with the exception of occasional \"shortness of breath.\" Her physical examination is unremarkable with the exception of a \"snap\"-like sound after S2, followed by a rumbling murmur. You notice that this murmur is heard best at the cardiac apex. A history of which of the following are you most likely to elicit upon further questioning of this patient?", "answer": "Repeated episodes of streptococcal pharyngitis as a child", "options": {"A": "Family history of aortic valve replacement at a young age", "B": "Hyperflexibility, vision problems, and pneumothorax", "C": "Systolic click auscultated on physical exam 10 years prior", "D": "Repeated episodes of streptococcal pharyngitis as a child", "E": "Cutaneous flushing, diarrhea, and bronchospasm"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old man comes to the emergency department because of shortness of breath and palpitations for 3 hours. He has had similar episodes intermittently for 4 months. His pulse is 140/min and blood pressure is 90/60 mm Hg. An ECG shows irregular narrow-complex tachycardia with no discernable P waves. Emergent electrical cardioversion is performed and the patient reverts to normal sinus rhythm. Pharmacotherapy with sotalol is begun. Which of the following is the most likely physiologic effect of this drug?", "answer": "Decreased AV nodal conduction", "options": {"A": "Decreased AV nodal conduction", "B": "Increased ventricular repolarization rate", "C": "Decreased Purkinje fiber conduction", "D": "Increased myocyte inotropy", "E": "Increased K+ efflux from myocytes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 53-year-old man presents to your Louisiana gulf coast community hospital with 48 hours of profuse watery diarrhea and 24 hours of vomiting and chills. The patient has a past medical history significant for hypertension and hypercholesterolemia. The patient denies sick contacts or any interaction with animals for the last month. Two days ago the patient attended a family crawfish boil where oysters, boiled crabs, and crawfish were consumed. Stool occult blood was negative. What is the most likely etiology of the patient's symptoms?", "answer": "Vibrio vulnificus", "options": {"A": "Campylobacter jejuni", "B": "Listeria monocytogenes", "C": "Vibrio vulnificus", "D": "Brucella melitensis", "E": "Shigella dysenteriae"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 59-year-old presents with right-sided hemiparesis, right-sided sensory loss, leftward eye deviation, and slurred speech. A head CT is performed which is significant for a hyperdense lesion affecting the putamen. The patient has a history of hypertension treated with hydrochlorothiazide, but is non-adherent. Which of the following is most likely associated with the cause of this patient’s neurological deficits?", "answer": "Vessel lipohyalinosis and microaneurysm formation", "options": {"A": "Thrombotic development over ruptured atherosclerotic plaque", "B": "Vessel lipohyalinosis and microaneurysm formation", "C": "Amyloid deposition in small cortical vessels", "D": "Predisposed vessel rupture secondary to cortical atrophy", "E": "Saccular aneurysm rupture into the subarachnoid space"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old man is brought to the Emergency Department after 2 days of shortness breath, orthopnea, and lower limb edema. His past medical history is significant for hypertension and a myocardial infarction 3 years ago that required a coronary arterial bypass graft. He has not been able to take prescribed medicine in several months due to recent unemployment and issues with insurance. On admission, his blood pressure is 155/92 mmHg, heart rate is 102/min, respiratory rate is 24/min, and temperature is 36.4°C (97.5°F). On physical examination there are fine rales in both lungs, regular and rhythmic cardiac sounds with an S3 gallop and a grade II/VI holosystolic murmur. Initial laboratory tests are shown below:\nNa+ 140 mEq/L\nK+ 4.2 mEq/L\nCl- 105 mEq/L\nBUN 20 mg/dL\nCreatinine 0.8 mg/dL\nThe patient is stabilized and admitted to the hospital. The next day his blood pressure is 110/60 mmHg, heart rate is 110/min, respiratory rate is 18/min, and temperature is 36.4°C (97.5°F). This morning's laboratory tests are shown below:\nNa+  135 mEq/L\nK+ 3.2 mEq/L\nCl- 102 mEq/L\nBUN 45 mg/dL\nCreatinine 1.7 mg/dL\nWhich of the following best explains the changes seen in this patient?", "answer": "Diuretic therapy", "options": {"A": "Diuretic therapy", "B": "Cholesterol emboli", "C": "Chronic renal failure", "D": "Glomerular basement membrane damage", "E": "Urinary tract obstruction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old woman presents to discuss the results of her Pap smear. Her previous Pap smear 1 year ago showed atypical squamous cells of undetermined significance. This year the Pap smear was negative. She had a single pregnancy with a cesarean delivery. Currently, she and her partner do not use contraception because they are planning another pregnancy. She does not have any concurrent diseases and her family history is unremarkable. The patient is concerned about her previous Pap smear finding. She heard from her friend about a vaccine which can protect her against cervical cancer. She has never had such a vaccine and would like to be vaccinated. Which of the following answers regarding the vaccination in this patient is correct?", "answer": "HPV vaccination is not recommended for women older than 26 years of age.", "options": {"A": "The patient can receive the vaccine after the pregnancy test is negative.", "B": "The patient should receive this vaccination as soon as possible.", "C": "This vaccination does not produce proper immunity in people who had at least 1 abnormal cytology report, so is unreasonable in this patient.", "D": "The patient should undergo HPV DNA testing; vaccination is indicated if the DNA testing is negative.", "E": "HPV vaccination is not recommended for women older than 26 years of age."}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 9-year-old girl is brought to the emergency room by her parents with severe shortness of breath, cough, and wheezing after playing with her friends in the garden. She has a history of bronchial asthma. Her vital signs are as follows: respiratory rate 39/min, pulse 121/min, blood pressure 129/67 mm Hg, and temperature 37.2°C (99°F). On physical exam, she looks confused and has bilateral diffuse wheezes on chest auscultation. Which of the following is the most appropriate drug to rapidly reverse her respiratory distress?", "answer": "Inhaled albuterol", "options": {"A": "Inhaled cromolyn", "B": "Intravenous propranolol", "C": "Inhaled beclomethasone", "D": "Inhaled albuterol", "E": "Oral montelukast"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman presents to the emergency department due to new-onset symptoms of asthma. She reports that the asthmatic attacks started a week ago. The past medical history includes gastroesophageal reflux disease and hepatitis B. On physical examination, the patient has bilateral foot drop as well as numbness and tingling sensation in all extremities. A complete blood count is relevant for eosinophilia of 9.1 × 108/L. Which of the markers below could explain all of the patient’s current symptoms?", "answer": "p-ANCA", "options": {"A": "ESR", "B": "p-ANCA", "C": "HLA B-27", "D": "Anti-Ro/SSA", "E": "Anti-histone antibodies"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man is brought to the physician for a follow-up examination. Three weeks ago, he was hospitalized and treated for spontaneous bacterial peritonitis. He has alcoholic liver cirrhosis and hypothyroidism. His current medications include spironolactone, lactulose, levothyroxine, trimethoprim-sulfamethoxazole, and furosemide. He appears ill. His temperature is 36.8°C (98.2°F), pulse is 77/min, and blood pressure is 106/68 mm Hg. He is oriented to place and person only. Examination shows scleral icterus and jaundice. There is 3+ pedal edema and reddening of the palms bilaterally. Breast tissue appears enlarged, and several telangiectasias are visible over the chest and back. Abdominal examination shows dilated tortuous veins. On percussion of the abdomen, the fluid-air level shifts when the patient moves from lying supine to right lateral decubitus. Breath sounds are decreased over both lung bases. Cardiac examination shows no abnormalities. Bilateral tremor is seen when the wrists are extended. Genital examination shows reduced testicular volume of both testes. Digital rectal examination and proctoscopy show hemorrhoids. Which of the following potential complications of this patient's condition is the best indication for the placement of a transjugular intrahepatic portosystemic shunt (TIPS)?", "answer": "Recurrent variceal hemorrhage", "options": {"A": "Hepatic veno-occlusive disease", "B": "Recurrent variceal hemorrhage", "C": "Portal hypertensive gastropathy", "D": "Hepatic encephalopathy", "E": "Hepatic hydrothorax"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Three days after delivery of a male newborn, a 36-year-old gravida 1, para 1 woman has fever and pain in her left leg. Pregnancy was complicated by premature rupture of membranes; the child was delivered at 35 weeks' gestation by lower segment transverse cesarean section because of a nonreassuring fetal heart rate. The patient has smoked half a pack of cigarettes daily for 5 years and continued to smoke during her pregnancy. Her temperature is 38.9°C (102°F), pulse is 110/min, and blood pressure is 110/80 mm Hg. Examination shows an edematous, erythematous, and warm left leg. Passive dorsiflexion of the left foot elicits pain in the calf. The peripheral pulses are palpated bilaterally. The uterus is nontender and palpated at the umbilicus. Ultrasonography of the left leg shows an incompressible left popliteal vein. Which of the following is the most appropriate initial step in management?", "answer": "Low molecular weight heparin", "options": {"A": "Low molecular weight heparin", "B": "Embolectomy", "C": "Urokinase", "D": "Warfarin", "E": "Graduated compression stockings"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Three hours later, the patient is reassessed. Her right arm is put in an elevated position and physical examination of the extremity is performed. The examination reveals reduced capillary return and peripheral pallor. Pulse oximetry of her right index finger on room air shows an oxygen saturation of 84%. Which of the following is the most appropriate next step in management?", "answer": "Perform escharotomy", "options": {"A": "Perform fasciotomy", "B": "Perform right upper extremity amputation", "C": "Obtain split-thickness skin graft", "D": "Decrease rate of IV fluids", "E": "Perform escharotomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 65-year-old man comes to the emergency department because of sudden, worsening pain in his right calf and foot that started 30 minutes ago. He also has a tingling sensation and weakness in his right leg. He has had no similar episodes, recent trauma, or claudication. He has type 2 diabetes mellitus and was diagnosed with hypertension 20 years ago. His sister has systemic sclerosis. He works as an office administrator and sits at his desk most of the day. He has smoked one and a half packs of cigarettes daily for 30 years. Current medications include metformin and lisinopril. His pulse is 110/min, respirations are 16/min, and blood pressure is 140/90 mm Hg. His right leg is pale and cool to touch. Muscle strength in his right leg is mildly reduced. Pedal pulses are absent on the right. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Arterial embolism", "options": {"A": "Arterial vasospasm", "B": "Popliteal artery aneurysm", "C": "Atherosclerotic narrowing of the artery", "D": "Arterial embolism", "E": "Atheroembolism"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old woman comes to the physician because of a 3-day history of lower abdominal pain and dysuria. She has a history of recurring urinary tract infections that have resolved with antibiotic treatment. She is sexually active with one male partner and they do not use condoms. She had mild pain during her last sexual intercourse one week ago. Her temperature is 38.2°C (100.8°F), pulse is 86/min, and blood pressure is 110/70 mm Hg. Physical examination shows lower abdominal tenderness and bilateral inguinal lymphadenopathy. There is a small amount of purulent vaginal discharge. Bimanual examination shows uterine and cervical motion tenderness. Laboratory studies show:\nHemoglobin 12 g/dL\nLeukocyte count 13,500/mm3\nSegmented neutrophils 75%\nEosinophils 1%\nLymphocytes 22%\nMonocytes 2%\nPlatelet count 328,000/mm3\nErythrocyte sedimentation rate 82 mm/h\nUrine\nRBC 1–2/hpf\nWBC 0–1/hpf\nNitrite negative\nBacteria occasional\nUrine pregnancy test negative\nWhich of the following is the most appropriate pharmacotherapy?\"", "answer": "Intramuscular ceftriaxone and oral doxycycline", "options": {"A": "Oral metronidazole", "B": "Intramuscular leuprolide", "C": "Oral levofloxacin and azithromycin", "D": "Oral trimethoprim-sulfamethoxazole", "E": "Intramuscular ceftriaxone and oral doxycycline"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 33-year-old woman presents to a walk-in clinic for evaluation of some bumps around her eyes. The bumps are not itchy or painful. They have been getting larger since appearing last year. She has no other complaints. She has not sought out medical attention for the last 20 years due to lack of insurance coverage. Her medical history reveals no problems and she takes no medications. Her periods are regular. A review of systems reveals no other concerns. She does not drink, smoke, or use illicit drugs. Her vital signs show a heart rate of 86/min, respirations of 14/min, and blood pressure of 124/76 mm Hg. On examination, the rash is a series of small papules and plaques around her eyes. The rest of the examination is unremarkable. Which of the following initial blood tests are most appropriate at this time?", "answer": "Fasting lipid profile alone", "options": {"A": "Fasting blood glucose alone", "B": "Fasting blood glucose and lipid profile", "C": "Fasting lipid profile alone", "D": "Thyroid stimulating hormone alone", "E": "Fasting blood glucose, lipid profile, and thyroid stimulating hormone"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man comes to the physician because of a 2-day history of severe perianal pain and bright red blood in his stool. Examination shows a bulging, red nodule at the rim of the anal opening. Which of the following arteries is the most likely source of blood to the mass found during examination?", "answer": "Internal pudendal", "options": {"A": "Deep circumflex iliac", "B": "Internal pudendal", "C": "Median sacral", "D": "Inferior gluteal", "E": "Superior rectal"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old man attends an appointment with a fertility specialist together with his wife. The couple has been attempting to conceive for over 2 years but without success. She has recently undergone a comprehensive gynecological exam and all the results were normal. He states that he has no prior medical history to report. He says that he does have a low libido compared to other men of his age. On physical examination, he is observed to be of a lean build with a height of 6ft 3 inches with slight evidence of gynecomastia. His testes are small and underdeveloped. His lab tests show an elevation of LH and FSH, along with azoospermia. Which of the following is the most likely cause of this man’s infertility?", "answer": "Presence of Barr body", "options": {"A": "Absence of chloride channel", "B": "Primary ciliary dyskinesia", "C": "Androgen insensitivity", "D": "Absent GnRH production", "E": "Presence of Barr body"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old woman is hospitalized after a recent viral illness complicated by congestive heart failure. She has a past medical history of obesity and hypertension controlled on lisinopril but was otherwise healthy until she developed fatigue and edema after a recent viral illness. In the hospital, she is started on furosemide to manage her fluid status. On day 5 of her admission, the patient’s temperature is 100.0°F (37.8°C), blood pressure is 136/88 mmHg, pulse is 90/min, and respirations are 14/min. The patient continues to have normal heart sounds, but with crackles bilaterally on lung auscultation. Edema is 3+ up to the bilateral knees. On labs, her leukocyte count is now 13,000/mm^3, up from 9,000/mm^3 the day before. Differential shows that this includes 1,000 eosinophils/mm^3. Creatinine is 1.7 mg/dL from 1.0 mg/dL the day before. Which of the following is most likely expected on urinary analysis?", "answer": "Leukocyte esterase positive", "options": {"A": "Bacteria > 100 CFU/mL", "B": "Crystals", "C": "Leukocyte esterase positive", "D": "Nitrites positive", "E": "Red blood cell casts"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 36-year-old right-handed man presents with complaints of difficulty writing for the past 6 months. He denies right-hand weakness, numbness, pain, and trauma. He can do most normal activities with his right hand, but whenever he holds a pen and starts to write, he experiences painful muscle spasms in his hand and arm. He is an account clerk by profession, and this problem causes him so much distress that he has started writing with his left hand. He is physically active. Sleep and appetite are normal. Past medical history is unremarkable. Physical examination is completely within normal limits with normal muscle tone, strength, and deep tendon reflexes. When he is asked to hold a pen and write, his hand becomes twisted with abnormal posturing while attempting to write. What is the next step in the management of this patient?", "answer": "Botulinum injection", "options": {"A": "Botulinum injection", "B": "Electroencephalogram", "C": "Refer to the psychiatry clinic", "D": "Selective serotonin reuptake inhibitor", "E": "Wrist splint"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 37-year-old G1P0 at 15 weeks gestation presents for an amniocentesis after a routine triple screen demonstrated a mildly elevated serum AFP. A chromosomal analysis revealed the absence of a second sex chromosome. Which of the following features will the infant most likely have?", "answer": "Streak ovaries", "options": {"A": "Mental retardation", "B": "Macroglossia", "C": "Micrognathia", "D": "Cystic kidneys", "E": "Streak ovaries"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old boy is brought to his primary care physician for evaluation of visual loss and is found to have lens subluxation. In addition, he is found to have mild scoliosis that is currently being monitored. Physical exam reveals a tall and thin boy with long extremities. Notably, his fingers and toes are extended and his thumb and little finger can easily encircle his wrist. On this visit, the boy asks his physician about a friend who has a very similar physical appearance because his friend was recently diagnosed with a pheochromocytoma. He is worried that he will also get a tumor but is reassured that he is not at increased risk for any endocrine tumors. Which of the following genetic principles most likely explains why this patient and his friend have a similar physical appearance and yet only one is at increased risk of tumors?", "answer": "Locus heterogeneity", "options": {"A": "Anticipation", "B": "Incomplete penetrance", "C": "Locus heterogeneity", "D": "Pleiotropy", "E": "Variable expression"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 19-year-old woman comes to the physician because of increased sweating for the past 6 months. She experiences severe sweating that is triggered by stressful situations and speaking in public. She is failing one of her university classes because of her avoidance of public speaking. She has not had any fevers, chills, weight loss, or night sweats. Her temperature is 36.6°C (98°F). Physical examination shows moist skin in the axillae and on the palms, soles, and face. Which of the following drugs is most likely to be effective for this patient's condition?", "answer": "Glycopyrrolate", "options": {"A": "Pilocarpine", "B": "Oxytocin", "C": "Physostigmine", "D": "Phenylephrine", "E": "Glycopyrrolate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 73-year-old man is admitted to the hospital for jaundice and weight loss. He is an immigrant from the Dominican Republic and speaks little English. A CT scan is performed showing a large mass at the head of the pancreas. When you enter the room to discuss these results with the patient, his daughter and son ask to speak with you outside of the patient's room. They express their desire to keep these results from their father, who is \"happy\" and would prefer not to know his poor prognosis. What is the appropriate response in this situation?", "answer": "Explore the reasoning behind the children's reluctance to have their father know his prognosis", "options": {"A": "Explore the reasoning behind the children's reluctance to have their father know his prognosis", "B": "Tell the children that you are obligated to tell the father his prognosis", "C": "Respect the children's wishes to hold prognosis information from their father", "D": "Deliver the information in English so that you have not withheld information but the patient will not understand", "E": "Bring the situation to the hospital ethics panel"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old man is seen in the hospital for new onset shortness of breath. The patient was hospitalized 5 days ago after initially presenting with chest pain. He was found to have an ST-elevation myocardial infarction. He underwent percutaneous coronary intervention with stent placement with resolution of his chest pain. He states that he was doing well until yesterday when he developed dyspnea while walking around the hall and occasionally when getting out of bed to use the bathroom. His shortness of breath has since progressed, and he is now having trouble breathing even at rest. His medical history is also significant for type II diabetes mellitus and hypercholesterolemia. He takes aspirin, clopidogrel, metformin, and atorvastatin. His temperature is 97°F (36.1°C), blood pressure is 133/62, pulse is 90/min, respirations are 20/min, and oxygen saturation is 88% on room air. On physical examination, there is a holosystolic murmur that radiates to the axilla and an S3 heart sound. Coarse crackles are heard bilaterally. An electrocardiogram, a chest radiograph, and cardiac enzyme levels are pending. Which of the following is the most likely diagnosis?", "answer": "Papillary muscle rupture", "options": {"A": "Dressler syndrome", "B": "Free wall rupture", "C": "Interventricular septum rupture", "D": "Papillary muscle rupture", "E": "Thickened mitral valve leaflets"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A mother brings her 2-year-old son to your office after she noticed a “sore on the back of his throat.” She states that her son had a fever and was complaining of throat pain 2 days ago. The child has also been fussy and eating poorly. On examination, the child has met all appropriate developmental milestones and appears well-nourished. He has submandibular and anterior cervical lymphadenopathy. On oral examination, less than 10 lesions are visible on bilateral tonsillar pillars and soft palate with surrounding erythema. After 4 days, the lesions disappear without treatment. Which of the following is the most likely causative agent?", "answer": "Coxsackievirus A", "options": {"A": "Type 2 sensitivity reaction", "B": "Herpes simplex virus type 1", "C": "Coxsackievirus A", "D": "Varicella-zoster", "E": "Staphylococcus aureus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "You are called to the bedside of a 75-year-old woman, who is post-op day 4 from a right total hip replacement. The patient appears agitated; she is trying to pull out her IV, and for the past 4 hours she has been accusing the nursing staff of trying to poison her. Her family notes that this behavior is completely different from her baseline; she has not shown any signs of memory loss or behavioral changes at home prior to the surgery. You note that she still has an indwelling catheter. She continues on an opioid-based pain regimen. All of the following are potential contributors to the patient’s presentation EXCEPT:", "answer": "Amyloid accumulation", "options": {"A": "Infection", "B": "Polypharmacy", "C": "Amyloid accumulation", "D": "Volume depletion", "E": "Electrolyte abnormalities"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 53-year-old man presents to the emergency department with a complaint of chest pain for 5 hours. The chest pain is continuous and squeezing in nature, not relieved by aspirin, and not related to the position of respiration. The blood pressure was 102/64 mm Hg, and the heart rate was 73/min. On physical examination, heart sounds are normal on auscultation. His ECG shows sinus rhythm with ST-segment elevation in leads II and III, aVF, and reciprocal segment depression in precordial leads V1–V6. Tissue plasminogen activator therapy is administered to the patient intravenously within 1 hour of arrival at the hospital. After 6 hours of therapy, the patient’s clinical condition starts to deteriorate. An ECG now shows ventricular fibrillation. The patient dies, despite all the efforts made in the intensive care unit. What is the most likely pathological finding to be expected in his heart muscles on autopsy?", "answer": "Coagulative necrosis", "options": {"A": "Caseous necrosis", "B": "Coagulative necrosis", "C": "Fat necrosis", "D": "Liquefactive necrosis", "E": "Fibrinoid necrosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 44-year-old man presents to the clinic with recurrent epigastric pain following meals for a month. He adds that the pain radiates up his neck and throat. Over the counter antacids have not helped. On further questioning, he endorses foul breath upon waking in the morning and worsening of pain when lying down. He denies any recent weight loss. His temperature is 37°C  (98.6°F), respirations are 15/min, pulse is 70/min, and blood pressure is 100/84 mm Hg. A physical examination is performed which is within normal limits except for mild tenderness on deep palpation of the epigastrium. An ECG performed in the clinic shows no abnormalities. What is the next best step in the management of this patient?", "answer": "Lansoprazole", "options": {"A": "Endoscopy", "B": "Barium swallow", "C": "Lansoprazole", "D": "Liquid antacid", "E": "Ranitidine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old woman, gravida 3, para 2, at 35 weeks' gestation is brought to the emergency department for the evaluation of lower abdominal and back pain and vaginal bleeding that started one hour ago. She has had no prenatal care. Her first two pregnancies were uncomplicated and her children were delivered vaginally. The patient smoked one pack of cigarettes daily for 20 years; she reduced to half a pack every 2 days during her pregnancies. Her pulse is 80/min, respirations are 16/min, and blood pressure is 130/80 mm Hg. The uterus is tender, and regular hypertonic contractions are felt every 2 minutes. There is dark blood on the vulva, the introitus, and on the medial aspect of both thighs bilaterally. The fetus is in a cephalic presentation. The fetal heart rate is 158/min and reactive with no decelerations. Which of the following is the most appropriate next step in management?", "answer": "Vaginal delivery", "options": {"A": "Transvaginal ultrasonography", "B": "Vaginal delivery", "C": "Elective cesarean delivery", "D": "Administration of betamethasone", "E": "Administration of terbutaline"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old woman presents with right lower quadrant abdominal pain, fatigue, and low-volume diarrhea of intermittent frequency for the past 4 months. She also reports weight loss and believes it to be due to a decreased appetite. She has noticed herself being more \"forgetful\" and she denies seeing any blood in her stool, changes in diet, infection, or recent travel history. Her temperature is 99.5°F (37.5°C), blood pressure is 112/72 mmHg, pulse is 89/min, and respirations are 17/min. Physical examination is unremarkable. Laboratory testing is shown below:\n\nHemoglobin: 10.8 g/dL\nHematocrit: 32%\nPlatelet count: 380,000/mm^3\nMean corpuscular volume: 118 µm^3\nReticulocyte count: 0.27%\nLeukocyte count: 9,900 cells/mm^3 with normal differential\nErythrocyte sedimentation rate: 65 mm/h\n\nA colonoscopy is performed and demonstrates focal ulcerations with polypoid mucosal changes adjacent to normal appearing mucosa. A biopsy is obtained and shows ulcerations and acute and chronic inflammatory changes. Involvement of which of the following sites most likely explains this patient's clinical presentation?", "answer": "Ileum", "options": {"A": "Colon", "B": "Gastric antrum", "C": "Gastric fundus", "D": "Ileum", "E": "Jejunum"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old man with a history of untreated HIV presents with fever, shortness of breath, and a nonproductive cough for the past week. Past medical history is significant for HIV diagnosed 10 years ago and never treated. His most recent CD4+ T cell count was 105/µL. Physical examination reveals bilateral crepitus over all lobes. No lymphadenopathy is present. A chest radiograph reveals bilateral infiltrates. Which of the following is the best treatment for this patient?", "answer": "Trimethoprim-sulfamethoxazole", "options": {"A": "Highly active antiretroviral therapy (HAART)", "B": "Trimethoprim-sulfamethoxazole", "C": "Ganciclovir", "D": "Azithromycin", "E": "Amphotericin B"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 1-week-old male newborn is brought to the physician for a follow-up examination after the results of newborn screening showed an increased serum concentration of phenylalanine. Genetic analysis confirms a diagnosis of phenylketonuria. The physician counsels the patient's family on the recommended dietary restrictions, including avoidance of artificial sweeteners that contain aspartame. Aspartame is a molecule composed of aspartate and phenylalanine and its digestion can lead to hyperphenylalaninemia in patients with phenylketonuria. Which of the following enzymes is primarily responsible for the breakdown of aspartame?", "answer": "Dipeptidase", "options": {"A": "Pepsin", "B": "Dipeptidase", "C": "Chymotrypsin", "D": "Trypsin", "E": "Carboxypeptidase A"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An American doctor is on an outreach trip to visit local communities in Ethiopia. In one clinic, he found many cases of children ages 2–5 years who have significantly low weight and height for their age. These children also had pale sclerae, distended abdomens, dermatoses, and marked edema in the lower extremities. Malnutrition in these patients is investigated and classified as (kwashiorkor) protein malnutrition. Appropriate nutrition supplementation was ordered and shipped in for the affected families. Which of the following amino acids must be included for these patients?", "answer": "Methionine", "options": {"A": "Alanine", "B": "Tyrosine", "C": "Arginine", "D": "Glutamine", "E": "Methionine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Under what physiologic state is the endogenous human analog of nesiritide produced?", "answer": "Increased ventricular stretch", "options": {"A": "Increased external stress", "B": "Increased ventricular stretch", "C": "Increased intracranial pressure", "D": "Increased circulatory volume presenting to the kidneys", "E": "Decreased circulatory volume presenting to the kidneys"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 9-year-old boy is brought to the physician for a well-child examination. His mother says his teachers report him being easily distracted, lagging behind his classmates in most of the subjects, and frequently falling asleep during class. She says that her son has complained of leg pain on multiple occasions. He is at the 45th percentile for height and 35th percentile for weight. Vital signs are within normal limits. Examination shows ptosis and a high-arched palate. Muscle strength is decreased in the face and hands. Muscle strength of the quadriceps and hamstrings is normal. Sensation is intact. Percussion of the thenar eminence causes the thumb to abduct and then relax slowly. Which of the following is the most likely diagnosis?", "answer": "Myotonic dystrophy", "options": {"A": "Spinal muscular atrophy", "B": "McArdle disease", "C": "Myotonic dystrophy", "D": "Juvenile dermatomyositis", "E": "Duchenne muscular dystrophy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 56-year old man is brought in by ambulance to the emergency department and presents with altered consciousness, confabulation, and widespread rash. He is recognized as a homeless man that lives in the area with a past medical history is significant for traumatic brain injury 4 years ago and chronic gastritis. He also has a long history of alcohol abuse. His vital signs are as follows: blood pressure 140/85 mm Hg, heart rate 101/min, respiratory rate 15/min, and temperature 36.1°C (97.0°F). His weight is 56 kg (123.5 lb) and height is 178 cm (5.8 ft). The patient is lethargic and his speech is incoherent. Examination reveals gingival bleeding, scattered corkscrew body hair, bruises over the forearms and abdomen, multiple petechiae, and perifollicular, hyperkeratotic papules over his extremities. His lung and heart sounds are normal. Abdominal palpation reveals tenderness over the epigastric area and hepatomegaly. Neurologic examination demonstrates symmetrically diminished reflexes in the lower extremities. Impairment of which of the following processes is the most likely cause of this patient’s hyperkeratotic rash?", "answer": "Hydroxylation of proline residues", "options": {"A": "Hydroxylation of proline residues", "B": "Carboxylation of clotting factors", "C": "Decarboxylation of histidine", "D": "Deamination of guanine", "E": "Ethanol oxidation to acetaldehyde"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 8-year-old girl is brought to the emergency department by her parents because she complained of very fast heartbeats. The patient has previously been healthy without any childhood illnesses and has not needed to visit a physician in the past 2 years. On examination, the heart rate is 198/min. Further examination by the physician reveals a grade III holosystolic murmur over the anterior chest wall. ECG is immediately performed after her heart rate is reduced, and shows a short P-R interval with a slow upstroke of the QRS complex. Which of the following is the most likely diagnosis in this patient?", "answer": "Ebstein anomaly", "options": {"A": "Pulmonic stenosis", "B": "Tricuspid atresia", "C": "Ebstein anomaly", "D": "Tetralogy of Fallot", "E": "Atrial septal defect"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 78-year-old man with advanced lung cancer with metastases to the brain is brought to the physician by his daughter, with whom he lives. The daughter reports that her father's condition has been slowly deteriorating over the past 2 months. His seizures have been poorly controlled despite maximal medical therapy. He has had progressive loss of mobility, a decrease in executive function, and worsening pain. The patient has Medicaid insurance. Current medications include high-dose corticosteroids and immediate-release opioid analgesics. The need for increased assistance has been distressing to the family, and they are concerned about the patient's overall comfort. The daughter asks the physician about her father's eligibility for hospice care. Which of the following responses from the physician about this model of care is most appropriate?", "answer": "\"\"\"Your father is only eligible if his life expectancy is less than 6 months.\"\"\"", "options": {"A": "\"\"\"Hospice care is likely to hasten your father's death.\"\"\"", "B": "\"\"\"Your father would have to be moved from home to a center that specializes in hospice care.\"\"\"", "C": "\"\"\"Your father cannot enter hospice care if there is a definitive cure for his disease.\"\"\"", "D": "\"\"\"Your father is only eligible if his life expectancy is less than 6 months.\"\"\"", "E": "\"\"\"Your father's current medication regimen is incompatible with hospice care because of the risk of respiratory depression.\"\"\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 26-year-old G1P0 mother is in the delivery room in labor. Her unborn fetus is known to have a patent urachus. Which of the following abnormalities would you expect to observe in the infant?", "answer": "Urine discharge from umbilicus", "options": {"A": "Myelomeningocele", "B": "Gastroschisis", "C": "Omphalocele", "D": "Meconium discharge from umbilicus", "E": "Urine discharge from umbilicus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 44-year-old woman is being treated by her oncologist for metastatic breast cancer. The patient had noticed severe weight loss and a fixed breast mass over the past 8 months but refused to see a physician until her husband brought her in. Surgery is scheduled, and the patient is given an initial dose of radiation therapy to destroy malignant cells. Which of the following therapies was administered to this patient?", "answer": "Induction therapy", "options": {"A": "Adjuvant therapy", "B": "Consolidation therapy", "C": "Induction therapy", "D": "Maintenance therapy", "E": "Salvage therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 50-year-old man presents to the emergency department with chief complaints of abdominal pain, distension, and bloody diarrhea for a day. Abdominal pain was episodic in nature and limited to the left lower quadrant. It was also associated with nausea and vomiting. He also has a history of postprandial abdominal pain for several months. He had an acute myocardial infarction which was treated with thrombolytics 3 months ago. He is a chronic smoker and has been diagnosed with diabetes mellitus for 10 years. On physical examination, the patient is ill-looking with a blood pressure of 90/60 mm Hg, pulse 100/min, respiratory rate of 22/min, temperature of 38.0°C (100.5°F) with oxygen saturation of 98% in room air. The abdomen is tender on palpation and distended. Rectal examination demonstrates bright red color stool. Leukocyte count is 14,000/mm3. Other biochemical tests were within normal ranges. Abdominal X-ray did not detect pneumoperitoneum or air-fluid level. The recent use of antibiotics was denied by the patient and stool culture was negative for C. difficile. Contrast-enhanced CT scan revealed segmental colitis involving the distal transverse colon. What is the most likely cause of the patient’s symptoms?", "answer": "Atherosclerosis", "options": {"A": "Hypokalemia", "B": "Aneurysm", "C": "Clostridium difficile infection", "D": "Embolism", "E": "Atherosclerosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 46-year-old man comes to the physician for routine physical examination. His blood pressure is 158/96 mm Hg. Physical examination shows no abnormalities. Serum studies show a potassium concentration of 3.1 mEq/L. His plasma aldosterone concentration (PAC) to plasma renin activity (PRA) ratio is 47 (N < 10). A saline infusion test fails to suppress aldosterone secretion. A CT scan of the abdomen shows bilateral adrenal gland abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Eplerenone therapy", "options": {"A": "Bilateral adrenalectomy", "B": "Eplerenone therapy", "C": "Amiloride therapy", "D": "Unilateral adrenalectomy", "E": "Propranolol therapy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "In a routine medical examination, an otherwise healthy 12-year-old by is noted to have tall stature with a wide arm span and slight scoliosis. Chest auscultation reveals a heart murmur. Transthoracic echocardiography shows an enlarged aortic root and aortic valve insufficiency. Mutations in mutations in fibrillin-1 gene are positive. Plasma homocysteine levels are not elevated. This patient is at high risk for which of the following complications?", "answer": "Aortic aneurysm", "options": {"A": "Arterial and visceral rupture", "B": "Aortic aneurysm", "C": "Thrombotic events", "D": "Infertility", "E": "Pheochromocytoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 5-day-old boy is brought to the emergency department by his mother because of a 2-day history of difficulty feeding and multiple episodes of his lips turning blue. He was born at home via spontaneous vaginal delivery and Apgar scores were 7 and 8 at 1 and 5 minutes, respectively. Physical examination shows grunting and moderate intercostal and subcostal retractions. Echocardiography shows a single vessel exiting from the heart. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Failure of neural crest cell migration", "options": {"A": "Failure of neural crest cell migration", "B": "Insufficient growth of endocardial cushions", "C": "Abnormal placement of the infundibular septum", "D": "Absent fusion of septum primum and septum secundum", "E": "Abnormal cardiac looping"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 58-year-old woman presents to her primary care doctor with her husband. The patient's husband reports that his wife has been acting \"funny\" ever since she was in a motor vehicle accident 2 months ago. She's been very rude to him, their children, and her friends, often saying inappropriate things. She is not interested in her previous hobbies and will not watch her favorite television shows or play cards. Which of the following regions is suspicious for injury?", "answer": "Frontal lobe", "options": {"A": "Broca's area", "B": "Occipital lobe", "C": "Temporal lobe", "D": "Motor cortex", "E": "Frontal lobe"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old woman presents to a psychiatrist to discuss a recent event in her life. At a social function 2 days back, she met a man who introduced himself as having worked with her at another private company 3 years ago. However, she did not recognize him. She also says that she does not remember working at any such company at any time during her life. However, the patient’s husband says that she had indeed worked at that company for three months and had quit due to her boss’s abusive behavior towards her. The man who met her at the function had actually been her colleague at that job. The woman asks the doctor, “How is it possible? I am really not able to recall any memories of having worked at any such company. What’s going on here?”. Her husband adds that after she quit the job, her mood frequently has been low. The patient denies any crying episodes, suicidal ideas, not enjoying recreational activities or feelings of worthlessness. Her appetite and sleep patterns are normal. She is otherwise a healthy woman with no significant medical history and lives a normal social and occupational life. The patient reports no history of smoking, alcohol, or substance use. On physical examination, she is alert and well-oriented to time, place and person. During memory testing, she correctly remembers the date of her marriage that took place 5 years back and the food she ate over the last 2 days. Which of the following is the most likely diagnosis in this patient?", "answer": "Dissociative amnesia", "options": {"A": "Pseudodementia", "B": "Dissociative amnesia", "C": "Dissociative identity disorder", "D": "Dissociative fugue", "E": "Transient global amnesia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old boy is brought by his parents to the physician for a fever for the past 2 days. His temperature is 101.3°F (38.5°C). His medical history is significant for sickle cell disease and recurrent infections. A year ago, he underwent spleen scintigraphy with technetium-99m that revealed functional hyposplenism. Which of the following findings would be found in a peripheral blood smear from this patient?", "answer": "Howell-Jolly bodies", "options": {"A": "Acanthocytes", "B": "Basophilic stippling", "C": "Heinz bodies", "D": "Howell-Jolly bodies", "E": "Schistocytes"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old woman presents to the emergency department multiple times over the past 3 months feeling like her chest is about to explode. She has been screened on several occasions for acute coronary syndrome, but each time, her cardiac enzymes have all been within normal limits. She comes into the emergency room diaphoretic, short of breath, and complaining of chest pain. Her symptoms usually resolve within 30 minutes, but she is left with a lingering fear for the next attack. She does not know of any triggers for these episodes. After medical causes are ruled out, the patient is referred to outpatient psychiatry to confirm her most likely diagnosis. Which one of the following is correct regarding this patient’s most likely condition?", "answer": "The patient must have symptoms of elevated autonomic activity.", "options": {"A": "The patient must have symptoms of elevated autonomic activity.", "B": "Attacks occur at regular intervals.", "C": "There is a fixed number of attacks needed for diagnosis.", "D": "The patients must have symptoms for at least 3 months.", "E": "The patient must have a fear of not being able to escape."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 18-month-old toddler is brought to a pediatric hematologist by his father. The boy was referred to this office for prolonged neutropenia. He has had several blood tests with an isolated low neutrophil count while hemoglobin, hematocrit, and platelet count is normal. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Today his complete blood count (CBC) with differential shows:\nHemoglobin: 15.5 g/dL\nPlatelets: 300,000 mm3\nNeutrophils: 20%\nBands: 2%\nLymphocytes: 40%\nMonocytes: 15%\nToday, he has a heart rate of 90/min, respiratory rate of 22/min, blood pressure of 110/65 mm Hg, and temperature of 37.0°C (98.6°F). On physical exam, the child appears healthy and is within expected growth parameters for his age and sex. A bone marrow biopsy shows normal bone marrow with 95% cellularity and trilineage maturation. Flow cytometry is normal with no abnormal markers noted. Which of the following is the most probable diagnosis in the present case?", "answer": "Chronic benign neutropenia", "options": {"A": "Chronic benign neutropenia", "B": "Chronic lymphoblastic leukemia", "C": "Sepsis", "D": "Aplastic anemia", "E": "Acute lymphoblastic leukemia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the physician for a routine checkup. She was recently adopted and has never seen a doctor before. The patient's parents state she was very emaciated when they adopted her and noticed she has trouble seeing in the evening. They also noted that she was experiencing profuse foul-smelling diarrhea as well, which is currently being worked up by a gastroenterologist. Her temperature is 97.8°F (36.6°C), blood pressure is 104/54 mmHg, pulse is 100/min, respirations are 19/min, and oxygen saturation is 98% on room air. The girl appears very thin. She has dry skin noted on physical exam. Laboratory studies are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 4,500/mm^3 with normal differential\nPlatelet count: 191,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 3.8 mEq/L\nHCO3-: 28 mEq/L\nBUN: 20 mg/dL\nGlucose: 88 mg/dL\nCreatinine: 0.7 mg/dL\nCa2+: 9.0 mg/dL\n\nWhich of the following findings is also likely to be seen in this patient?", "answer": "Xerophthalmia", "options": {"A": "Ataxia", "B": "Cheilosis", "C": "Diarrhea", "D": "Perifollicular hemorrhages", "E": "Xerophthalmia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old man presents to the emergency department with vomiting, diarrhea, and abdominal pain 2 hours after eating seafood in a restaurant. He also mentions that immediately after ingestion of the food, he experienced tingling and numbness over the lips and face. On physical examination, his vital signs are stable. On neurological examination, he has reduced strength in the lower extremities, but deep tendon reflexes are present and normal. Laboratory evaluation of the seafood from the restaurant confirms the presence of a toxin which is known to block voltage-gated fast sodium channels. Which of the following toxins is the most likely cause of the patient’s symptoms?", "answer": "Tetrodotoxin", "options": {"A": "Latrotoxin", "B": "Domoic acid", "C": "Okadaic acid", "D": "Scombrotoxin", "E": "Tetrodotoxin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old woman presents with a 3-month history of bloody diarrhea and intermittent abdominal pain. She says that after she has a bowel movement, she still feels as though she needs to go more. She also reports a 10-pound weight loss, significant fatigue, and frequent cravings to chew ice. Her past medical history is significant only for chronic iron deficiency anemia since high school. She currently takes a women’s multivitamin and ferrous sulfate 65 mg orally once daily. She is on the college track team but now is too tired to participate in practice. Her family history is significant for colon cancer and her grandmother died from breast cancer in her 70’s. Her vital signs include: temperature 37.0°C (98.6°F), pulse 102/min, respiratory rate 16/min, blood pressure 100/75 mm Hg. Physical examination is significant for conjunctival pallor, koilonychia, and the cutaneous findings shown in the exhibit. Laboratory tests show elevated ESR and C-reactive protein and findings consistent with iron deficiency anemia. A barium enema demonstrates a lead pipe appearance and a loss of haustra. Which of the following are the recommended screening guidelines for colorectal cancer for this patient?", "answer": "Colonoscopy by age 32 and repeated every 1–2 years thereafter", "options": {"A": "Colonoscopy by age 32 and repeated every 1–2 years thereafter", "B": "Colonoscopy by age 50 and repeated every 10 years thereafter", "C": "Colonoscopy by age 32 and repeated every 3 years thereafter", "D": "Colonoscopy by age 45 and repeated every 10 years thereafter", "E": "Flexible sigmoidoscopy by age 32 and repeated every 1–2 years thereafter"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman presents to the emergency department with severe abdominal and lower back pain. She describes it as intense cramping and states that she experienced severe pain roughly 1 month ago that was similar. The patient's past medical history is non-contributory, and she states that her menses cause her to soak through 1 pad in a day. She is currently sexually active and does not use any contraception. Her vitals are within normal limits. The patient's abdominal exam is non-focal, and her pelvic exam reveals no adnexal masses or tenderness and no cervical motion tenderness. Which of the following is the most likely diagnosis?", "answer": "Primary dysmenorrhea", "options": {"A": "Adenomyosis", "B": "Appendicitis", "C": "Ectopic pregnancy", "D": "Leiomyoma", "E": "Primary dysmenorrhea"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Which of the following factors gives the elastin molecule the ability to stretch and recoil?", "answer": "Cross-links between lysine residues", "options": {"A": "Hydroxylation of proline and lysine rich regions", "B": "Cross-links between lysine residues", "C": "Elastase activity", "D": "Triple helix formation", "E": "Cleavage of disulfide rich terminal regions"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old woman, otherwise healthy, is admitted to the coronary care unit due to acute ischemic cardiomyopathy. No other significant past medical history. Her vital signs include: pulse 116/min, respiratory rate 21/min, temperature 37.4°C (99.3°F), and blood pressure 160/100 mm Hg. On physical examination, the patient is in distress. Cardiopulmonary exam is positive for bilateral pulmonary crackles at the lung bases, tachycardia, and jugular venous distension. Her laboratory findings are significant for a hemoglobin of 7.8 g/dL. She is initially treated with oxygen, antiplatelet therapy, nitroglycerin, and beta-blockers. In spite of these treatments, her angina does not subside. The patient is not a candidate for percutaneous coronary intervention, so she is being prepared for a coronary artery bypass graft. Which of the following would be the next, best step in management of this patient?", "answer": "Transfuse packed red blood cells", "options": {"A": "Administer intravenous iron", "B": "Transfuse packed red blood cells", "C": "Transfuse whole blood", "D": "Treat with erythropoietin", "E": "Observation and supportive care"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A goalkeeper of a famous soccer team gives an interview with a health agency regarding his childhood. He describes how when he was a child, he would constantly clear his throat in class and the teachers would write a note to his mother with advice to go see an ENT doctor. He complained of being restless, fidgety, and sometimes hyperactive in class, disrupting the environment and causing him many social problems. He would blurt out the answer at times and keep repeating it without any control, leading to some embarrassing timeouts. But he was always nice to his teachers, so he calls it a “benign frustration” rather than aggressively causing distress. He also talked about how his symptoms were dramatically improved with medication. Which of the following is an FDA approved drug for this patient’s most likely condition?", "answer": "Haloperidol", "options": {"A": "Clonazepam", "B": "Clonidine", "C": "Guanfacine", "D": "Haloperidol", "E": "Lithium"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 36-year-old healthy man presents to his physician to discuss his concerns about developing heart disease. His father, grandfather, and older brother had heart problems, and he has become increasingly worried he might be at risk. He takes no medications and his past medical history is only significant for an appendectomy at 20 years ago. He is married happily with 2 young children and works as a hotel manager and exercises occasionally in the hotel gym. He drinks 3–5 alcoholic beverages per week but denies smoking and illicit drug use. Today his blood pressure is 146/96 mm Hg, pulse rate is 80/min, and respiratory rate is 16/min. He has a body mass index of 26.8 kg/m2. His physical examination is otherwise unremarkable. Laboratory tests show:\nLaboratory test\nSerum glucose (fasting) 88 mg/dL\nSerum electrolytes \nSodium  142 mEq/L\nPotassium 3.9 mEq/L\nChloride 101 mEq/L\nSerum creatinine 0.8 mg/dl\nBlood urea nitrogen 10 mg/dl\nCholesterol, total 350 mg/dL\nHDL-cholesterol 40 mg/dL\nLDL-cholesterol 280 mg/dL\nTriglycerides 130 mg/dL\nBesides appropriate medications for his cholesterol and a follow-up for his hypertension, which of the following supplements is thought to provide a protective cardiovascular effect?", "answer": "Vitamin E", "options": {"A": "Folic acid", "B": "Thiamine", "C": "Vitamin B12", "D": "Vitamin E", "E": "Vitamin K"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old man comes to the emergency department for pain and swelling of his left knee one day after injuring it while playing soccer. While sprinting on the field, he slipped as he attempted to kick the ball and landed on the anterior aspect of his knee. He underwent an appendectomy at the age of 16 years. His vitals signs are within normal limits. Examination shows a swollen and tender left knee; range of motion is limited by pain. The tibial tuberosity shows tenderness to palpation. The left tibia is displaced posteriorly when force is applied to the proximal tibia after flexing the knee. The remainder of the examination shows no abnormalities. An x-ray of the left knee joint shows an avulsion fracture of the tibial condyle. Which of the following is the most likely diagnosis?", "answer": "Posterior cruciate ligament injury", "options": {"A": "Anterior cruciate ligament injury", "B": "Lateral meniscus injury", "C": "Posterior cruciate ligament injury", "D": "Medial meniscus injury", "E": "Medial collateral ligament injury"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 49-year-old woman comes to the physician with a 2-month history of mild abdominal pain, nausea, and several episodes of vomiting. She often feels full after eating only a small amount of food. Abdominal examination shows mild right upper quadrant tenderness and a liver span of 16 cm. Ultrasonography shows a 5 x 4 cm hyperechoic mass in the left lobe of the liver. The mass is surgically excised. A photomicrograph of the resected specimen is shown. Which of the following is the most likely diagnosis?", "answer": "Cavernous hemangioma", "options": {"A": "Hepatocellular adenoma", "B": "Alveolar echinococcosis", "C": "Cavernous hemangioma", "D": "Focal nodular hyperplasia", "E": "Angiosarcoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A pharmaceutical company has created an experimental medication, Drug Z, for patients with relapsing-remitting multiple sclerosis. Drug Z has been deemed to be safe in rats and is nearly ready for human trials. Before initiating a Phase I clinical trial, the company would like to study the medication’s pharmacokinetic properties in humans. The drug was found to have a half-life of 2.5 hours and is eliminated by first-order kinetics. The volume of distribution of the drug is determined to be 0.5 L/kg. The drug is administered intravenously and sublingually and plasma drug concentration vs. time plots are obtained. Intravenous administration of 10 mg of Drug Z yields an area under the curve (AUC) of 15 mg hr/L. Sublingual administration of 25 mg of Drug Z yields an area under the curve of 20 mg hr/L. What is the absolute bioavailability of this medication?", "answer": "53%", "options": {"A": "48%", "B": "53%", "C": "59%", "D": "67%", "E": "71%"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old homeless male presents with fever and cough. He was found unconscious on the side of the road and was brought to the emergency room. He is noticeably drunk and is unable to answer any questions. On physical exam his temperature is 103°F (40°C), blood pressure is 130/85 mmHg, pulse is 110/min, respirations are 23/min, and pulse oximetry is 96% on room air. You note decreased breath sounds in the right lower lobe. The pathogen most likely responsible for this patient's symptoms has which of the following features?", "answer": "Gram-negative organism that produces mucoid colonies on MacConkey agar", "options": {"A": "Organism that forms black colonies on cysteine-tellurite agar", "B": "Disc-shaped yeast seen on methenamine silver stain", "C": "Gram-positive, catalase-positive organism that forms cocci in clusters", "D": "Negative-sense, single-stranded RNA virus", "E": "Gram-negative organism that produces mucoid colonies on MacConkey agar"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old Caucasian male presents complaining of inability to open his mouth. Patient history reveals that he recently injured his foot from an exposed floor nail in his house. This patient's symptoms are likely the result of:", "answer": "Impaired motor neuron release of GABA", "options": {"A": "Impaired motor neuron release of ACh", "B": "Impaired motor neuron release of GABA", "C": "Increased production of gas in his soft tissues", "D": "Cross-reactivity of bacterial antigens", "E": "Bacterial infiltration of the central nervous system"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 18-year-old college student presents to the ED straight from chemistry lab where he ingested an unknown compound. He complains of a headache, and is flushed, tachypneic and tachycardic. Suspecting cyanide poisoning, you administer amyl nitrite which causes which of the following?", "answer": "Oxidation of ferrous iron in hemoglobin to ferric iron", "options": {"A": "Oxidation of ferrous iron in hemoglobin to ferric iron", "B": "A decrease in serum methemoglobin levels", "C": "Formation of thiocyanate", "D": "Chelation of the residue", "E": "Increase in intracellular NADH/NAD+ ratio"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 76-year-old man presents to his physician with his daughter for evaluation of memory loss and disorientation that has become progressively worse over the last few years. The patient’s daughter states that the memory loss started with her father forgetting things ''here and there'' and the memory loss has progressed to the patient forgetting the names of loved ones and getting lost in familiar places. The medical history is non-contributory. On examination, the patient is awake and alert but only oriented to self (not time or place). The cardiopulmonary and neurologic exams are within normal limits. Routine lab work is performed to rule out infection and is found to be within normal limits. Four years later the patient passes away and an autopsy is performed to confirm the presumptive diagnosis. Brain biopsy slides are shown. What histologic features confirm this patient’s diagnosis?", "answer": "Aβ amyloid neuritic plaques", "options": {"A": "Lewy bodies", "B": "Aβ amyloid neuritic plaques", "C": "Ubiquitinated TDP-43", "D": "Beta-pleated sheet proteins resistant to proteases", "E": "Viral inclusions within oligodendrocytes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 19-year-old female student presents to her physician for overall fatigue. She is having a hard time concentrating while studying and feeling tired most of the time. She also has had constipation for more than 3 weeks and rectal bleeding on occasions. She notices she is getting colder and often needs to wear warmer clothes than usual for the same weather. On examination, a small nodule around the size of 1cm is palpated in the left thyroid lobule; the gland is nontender. There is no lymphadenopathy. Her vital signs are: blood pressure is 118/75 mm Hg, respirations are 17/min, pulse is 87/min, and temperature is 36.1°C (97.0°F). Which of the following is the best next step in the management of this patient?", "answer": "Thyroid ultrasound", "options": {"A": "Serum T3 levels", "B": "Thyroid ultrasound", "C": "Serum calcitonin levels", "D": "Radionuclide thyroid scan", "E": "Combination T4 and T3 therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old man is brought to the emergency department because of severe back pain for 2 hours. He describes it as a stabbing pain between his scapulae that is 9 out of 10 in intensity. He has vomited once during this period. He has hypertension and type 2 diabetes mellitus. He has not seen a physician in 18 months. Current medications include metformin and enalapril. He is diaphoretic. His temperature is 37.3°C (99.1°F), pulse is 100/min, respirations are 20/min, and blood pressure is 210/130 mm Hg. He is not oriented to person, place, or time. The lungs are clear to auscultation. Cardiac examination shows no murmurs, rubs, or gallops. Abdominal examination shows mild epigastric tenderness with no rebound or guarding. The radial pulse is decreased on the left side. Laboratory studies show:\nHemoglobin 13.1 g/dL\nLeukocyte count 10,000/mm3\nPlatelet count 230,000/mm3\nSerum\nNa+ 139 mEq/L\nK+ 4.1 mEq/L\nCl- 103 mEq/L\nGlucose 230 mg/dL\nCreatinine 3.9 mg/dL\nAlkaline phosphatase 55 U/L\nUrine toxicology screening is positive for opiates and cocaine. An ECG shows sinus tachycardia with no evidence of ischemia. An x-ray of the chest shows a widened mediastinum. Which of the following is the most appropriate next step in management?\"", "answer": "Transesophageal echocardiography", "options": {"A": "Transthoracic echocardiography", "B": "Gadolinium-enhanced MRA", "C": "Contrast-enhanced CT angiography", "D": "Transesophageal echocardiography", "E": "Aortography\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old man presents to his primary care provider for routine follow-up. He complains of mild fatigue and occasional tingling in both feet. He reports that this numbness and tingling has led to him having 3 falls over the last month. He has had type 2 diabetes mellitus for 23 years and hypertension for 15 years, for which he takes metformin and enalapril. He denies tobacco or alcohol use. His blood pressure is 126/82 mm Hg, the heart rate is 78/min, and the respiratory rate is 15/min. Significant laboratory results are shown:\nHemoglobin 10 g/dL\nHematocrit 30%\nMean corpuscular volume (MCV) 110 fL\nSerum B12 level 210 picograms/mL\nWhich of the following is the best next step in the management of this patient’s condition?", "answer": "Methylmalonic acid level", "options": {"A": "Intrinsic factor antibody", "B": "Schilling test", "C": "Folic acid supplementation", "D": "Pregabalin or gabapentin", "E": "Methylmalonic acid level"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A previously healthy 31-year-old man comes to the emergency department because of acute onset of left flank pain radiating to his inner groin and scrotum for 3 hours. He also had nausea and one episode of hematuria. His only medication is a multivitamin. He appears uncomfortable. His temperature is 37°C (98.6°F), pulse is 104/min, respirations are 19/min, and blood pressure is 132/85 mm Hg. Physical examination shows marked tenderness in the left costovertebral area. He has normal skin turgor, a capillary refill time of < 1 second, and has been urinating normally. Laboratory studies show:\nSerum\nCalcium 9.5 mg/dL\nPhosphorus 4.3 mg/dL\nCreatinine 0.8 mg/dL\nUrea nitrogen 15 mg/dL\nUrine\npH 6.5\nRBCs 50–60/hpf\nA CT scan of the abdomen shows a 4-mm stone in the left distal ureter. Intravenous fluid resuscitation is begun and treatment with tamsulosin and ketorolac is initiated. Five hours later, he passes the stone. Metabolic analysis of the stone is most likely going to show which of the following?\"", "answer": "Calcium oxalate", "options": {"A": "Uric acid", "B": "Magnesium ammonium phosphate", "C": "Cystine", "D": "Xanthine", "E": "Calcium oxalate"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 50-year-old female teacher presents to the clinic with complaints of discoloration of the skin around the right ankle accompanied by itching. She began noticing it a month ago and the pruritus worsened over time. She also has some pain and swelling of the region every night, especially on days when she teaches late into the evening. Her past medical history is significant for diabetes mellitus type 2, for which she takes metformin. She lives with her husband and takes oral contraceptive pills. On examination, the physician observes hyperpigmentation of the medial aspect of her right ankle. The skin is dry, scaly, and edematous along with some superficial varicosities. Dorsiflexion of the foot is extremely painful. Peripheral pulses are equally palpable on both lower limbs. There is a small 2 cm ulcer noted near the medial malleolus with thickened neighboring skin and indurated edges. Laboratory studies show D-dimer of 1,000 µg/L and HbA1c of 9%. Doppler ultrasound of the lower extremity reveals an intramural thrombus in the popliteal vein. Which of the following is the most likely diagnosis in this patient?", "answer": "Stasis dermatitis", "options": {"A": "Basal cell carcinoma", "B": "Stasis dermatitis", "C": "Diabetic foot", "D": "Atopic dermatitis", "E": "Cellulitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old man comes to the physician because of a 2-month history of episodes of shortness of breath, lightheadedness, and palpitations. During the examination, he reports the onset of one such episode. His pulse is 170/min and regular, respirations are 22/min, and blood pressure is 100/65 mm Hg. An ECG shows a regular narrow complex tachycardia; no P waves are visible. A common clinical maneuver to diagnose and/or relieve the patient's symptoms involves stimulation of which of the following nerves?", "answer": "Glossopharyngeal", "options": {"A": "Trigeminal", "B": "Recurrent laryngeal", "C": "Facial", "D": "Phrenic", "E": "Glossopharyngeal"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old man comes to the physician because he believes he has low testosterone. He states that he is embarrassed at his lack of musculature, despite lifting weights twice daily. Every day, he drinks a gallon of milk and several protein shakes in addition to 3 large meals. He is convinced that his female classmates at the community college he attends are secretly laughing at his scrawny appearance. Over the course of the semester, he has attended fewer and fewer classes out of embarrassment and shame. He is also concerned that his hair is thinning and applies topical minoxidil to his scalp 3 times daily. He spends 2 hours daily anxiously examining himself in the mirror. Today, he is wearing a long-sleeved shirt and a hat. His BMI is 26 kg/m2. Physical examination shows no abnormalities. On mental status examination, he has an anxious mood and a full range of affect. Serum studies show a normal testosterone concentration. Which of the following is the most likely diagnosis?", "answer": "Body dysmorphic disorder", "options": {"A": "Avoidant personality disorder", "B": "Body dysmorphic disorder", "C": "Obsessive compulsive disorder", "D": "Binge eating disorder", "E": "Generalized anxiety disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Clinical study looks at the effect of childhood exposure of 2nd-hand smoking on the incidence of bronchogenic adenocarcinoma (BA). Study of 100 subjects (50 exposed to childhood 2nd-hand smoking and 50 healthy controls with no childhood exposure) involves monitoring the lifetime incidence of BA data from the study are shown in the table below:\nGroup\\BA Dx Yes No\nExposed 18 32\nControls 7 43\nWhich of the following statements is correct regarding the number needed to harm (NNH) based on this study?", "answer": "The NNH is inversely correlated with the relative risk increase.", "options": {"A": "If the incidence of BA increases in the control group, the NNH will decrease.", "B": "If the incidence of BA increases in the experimental group, the NNH will increase.", "C": "The NNH is 11.", "D": "The NNH is inversely correlated with the relative risk increase.", "E": "If the absolute risk in the exposed group increases, the NNH increases."}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Two patients are vaccinated for poliomyelitis. Patient A receives the Sabin oral vaccine, and Patient B receives the Salk intramuscular vaccine. Six weeks after their initial vaccinations, which of the following would be the greatest difference regarding these two patients?", "answer": "Patient A has a higher level of duodenal IgA antibodies", "options": {"A": "Patient A has a higher level of duodenal IgA antibodies", "B": "Patient B has a higher level of duodenal IgA antibodies", "C": "Patient A has a lower level of serum IgA antibodies", "D": "Patient B has a lower level of serum IgM antibodies", "E": "Patient A has a higher level of serum IgG antibodies"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 71-year-old woman comes to the physician because of dizziness and intermittent episodes of heart palpitations for 5 days. During this time, she has also had one episode of syncope. An ECG shows absence of P waves and irregular RR intervals. Treatment with an antiarrhythmic drug is initiated. The effect of the drug on the cardiac action potential is shown. Which of the following cardiac ion channels is most likely targeted by this drug?", "answer": "Voltage-gated potassium channels", "options": {"A": "Voltage-gated nonselective cation channels", "B": "Voltage-gated sodium channels", "C": "Voltage-gated potassium channels", "D": "Voltage-gated calcium channels", "E": "Voltage-gated chloride channels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old woman presents to her primary care physician in order to discuss the results of a biopsy. Two weeks ago, her mammogram revealed the presence of suspicious calcifications in her right breast, and she subsequently underwent biopsy of these lesions. Histology of the lesions revealed poorly cohesive cells growing in sheets with a nuclear to cytoplasmic ratio of 1:1. Furthermore, these cells were found to undergo invasion into the surrounding tissues. Given these findings, the patient is referred to an oncologist for further evaluation. Upon further imaging, the patient is found to have no lymph node adenopathy and no distant site metastases. Which of the following would most properly describe the lesions found in this patient?", "answer": "High grade and low stage", "options": {"A": "High grade and high stage", "B": "High grade and no stage", "C": "High grade and low stage", "D": "Low grade and high stage", "E": "Low grade and low stage"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A graduate student is developing the research design for a current project on the detection of ovarian tumor markers in mice. The main method requires the use of chromogenic substrates, in which a reaction may be interpreted according to an enzyme-mediated color change. The detection of which of the substances below is routinely used in clinical practice and applies the above-described method?", "answer": "P24 antigen", "options": {"A": "ABO blood types", "B": "Anti-D antibodies", "C": "P24 antigen", "D": "Epstein-Barr virus infection", "E": "Antibodies in autoimmune hemolytic anemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 12-year-old boy is brought to the physician because of a 6-day history of gradually worsening left knee pain. The pain is exacerbated by movement and kneeling. There is no pain at rest and no history of trauma to the knee. He is concerned because his soccer tryouts are in a few days. Vital signs are within normal limits. Examination shows mild swelling and tenderness to palpation of the left anterior, superior tibia. Extension of the left knee against resistance reproduces the knee pain; flexion is limited by pain. There is no local erythema or effusion of the left knee. A lateral view of an x-ray of his left knee is shown. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Traction apophysitis of the tibial tubercle", "options": {"A": "Impingement of the infrapatellar fat pad", "B": "Inflammation of the infrapatellar bursa", "C": "Chondromalacia patella", "D": "Traction apophysitis of the tibial tubercle", "E": "Osteochondritis dissecans of the knee"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old teenager presents to the clinic with her parents complaining of headaches and loss of vision which began insidiously 3 months ago. She describes her headaches as throbbing, mostly on her forehead, and severe enough to affect her daily activities. She has not experienced menarche. Past medical history is noncontributory. She takes no medication. Both of her parents are alive and well. Today, her blood pressure is 110/70 mm Hg, the heart rate is 90/min, the respiratory rate is 17/min, and the temperature is 37.0°C (98.6°F). Breasts and pubic hair development are in Tanner stage I. Blood work is collected and an MRI is performed (the result is shown). Inhibition of which of the following hormones is the most likely explanation for the patient's signs and symptoms?", "answer": "Gonadotropins", "options": {"A": "Antidiuretic hormone", "B": "Thyroid-stimulating hormone", "C": "Gonadotropins", "D": "Adrenocorticotropic hormone", "E": "Prolactin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A healthy 31-year-old woman comes to the physician because she is trying to conceive. She is currently timing the frequency of intercourse with at-home ovulation test kits. An increase in the levels of which of the following is the best indicator that ovulation has occurred?", "answer": "Progesterone", "options": {"A": "Estrogen", "B": "Gonadotropin-releasing hormone", "C": "Follicle stimulating hormone", "D": "Progesterone", "E": "Luteinizing hormone\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man presents with a 2-month history of increasing lethargy, frequent upper respiratory tract infections, and easy bruising. Past medical history is unremarkable. The patient reports a 14-pack-year smoking history and says he drinks alcohol socially. No significant family history. His vital signs include: temperature 36.8°C (98.2°F), blood pressure 132/91 mm Hg and pulse 95/min. Physical examination reveals conjunctival pallor and scattered ecchymoses on the lower extremities. Laboratory results are significant for the following:\nHemoglobin 8.2 g/dL\nLeukocyte count 2,200/mm3\nPlatelet count 88,000/mm3\nReticulocyte count 0.5%\nA bone marrow biopsy is performed, which demonstrates hypocellularity with no abnormal cell population. Which of the following is the most likely diagnosis in this patient? ", "answer": "Aplastic anemia", "options": {"A": "Aplastic anemia", "B": "Myelodysplastic syndrome", "C": "Infectious mononucleosis", "D": "Acute lymphocytic leukemia", "E": "Drug-induced immune pancytopenia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-year-old boy is brought to the physician for evaluation of delayed onset of speech. Over the past year, he has also had recurrent dizziness and three episodes of syncope. Examination of the ears shows clear auditory canals and intact tympanic membranes with normal light reflexes. Visual reinforcement audiometry shows bilateral sensorineural deafness. Genetic analysis reveals a mutation in the KCNQ1 gene causing a defect in slow voltage-gated potassium channels. An electrocardiogram of this patient is most likely to show which of the following?", "answer": "Prolongation of the QT interval", "options": {"A": "Pseudo-right bundle branch block", "B": "Slurred upstroke of the QRS complex", "C": "Epsilon wave following the QRS complex", "D": "Absence of P waves", "E": "Prolongation of the QT interval"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old man is brought to the emergency department 20 minutes after losing control over his bicycle and colliding with a parked car. The handlebar of the bicycle hit his lower abdomen. On arrival, he is alert and oriented. His pulse is 90/min, respirations are 17/min and blood pressure is 110/70 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. The pupils are equal and reactive to light. There are multiple bruises over his chest and lower extremities. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft and nontender. There is no pelvic instability. Rectal examination is unremarkable. A complete blood count, prothrombin time, and serum concentrations of glucose, creatinine, and electrolytes are within the reference range. Urine dipstick is mildly positive for blood. Microscopic examination of the urine shows 20 RBCs/hpf. Which of the following is the most appropriate next step in management?", "answer": "Observation and follow-up", "options": {"A": "Suprapubic catheterization", "B": "Intravenous pyelography", "C": "Laparotomy", "D": "Observation and follow-up", "E": "CT scan of the abdomen and pelvis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Four days after admission to the hospital for acute pancreatitis, a 41-year-old man develops hypotension and fever. His temperature is 39.1°C (102.3°F), pulse is 115/min, and blood pressure is 80/60 mm Hg. Physical examination shows warm extremities, asymmetric calf size, and blood oozing around his IV sites. There are numerous small, red, non-blanching macules and patches covering the extremities, as well as several large ecchymoses. His hemoglobin concentration is 9.0 g/dL. A peripheral blood smear shows schistocytes and decreased platelets. Which of the following sets of serum findings are most likely in this patient?\n $$$ Prothrombin time %%% Partial thromboplastin time %%% Fibrinogen %%% D-dimer $$$", "answer": "↑ ↑ ↓ ↑", "options": {"A": "↑ ↑ ↓ normal", "B": "Normal normal normal normal", "C": "↑ ↑ ↓ ↑", "D": "Normal ↑ normal normal", "E": "Normal normal normal ↑"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old man with a history of hypertension presents to his primary care physician for a headache and abdominal pain. His symptoms began approximately 1 week ago and have progressively worsened. He describes his headache as pressure-like and is mildly responsive to ibuprofen. His abdominal pain is located in the bilateral flank area. His hypertension is poorly managed with lifestyle modification and chlorthalidone. He had 1 urinary tract infection that was treated with ciprofloxacin approximately 6 months ago. He has a home blood pressure monitor, where his average readings are 155/95 mmHg. Family history is significant for his father expiring secondary to a myocardial infarction and his history was complicated by refractory hypertension and end-stage renal disease. His vital signs are significant for a blood pressure of 158/100 mmHg. Physical examination is notable for bilateral flank masses. Laboratory testing is significant for a creatinine of 3.1 mg/dL. Urinalysis is remarkable for hematuria and proteinuria. Which of the following will this patient most likely be at risk for developing?", "answer": "Mitral valve prolapse", "options": {"A": "Epilepsy", "B": "Lymphangioleiomyomatosis", "C": "Migraine headache", "D": "Mitral valve prolapse", "E": "Neuroendocrine pancreatic tumor"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old woman comes to the physician because of a 1-week history of nausea and vomiting. She has not had fever, abdominal pain, diarrhea, or vaginal bleeding. She does not remember the date of her last menstrual period. She uses oral contraceptive pills but occasionally forgot to take them. She had pelvic inflammatory disease 2 years ago and was treated with antibiotics. Her temperature is 37°C (98.6°F), pulse is 110/min, respirations are 16/min, and blood pressure is 118/75 mm Hg. Physical examination shows no abnormalities. Pelvic examination shows a normal appearing vagina, cervix, uterus, and adnexa. A urine pregnancy test is positive. Her serum β-human chorionic gonadotropin concentration is 805 mIU/mL. Which of the following is the most appropriate next step in diagnosis?", "answer": "Transvaginal ultrasound in 4 days", "options": {"A": "Diagnostic laparoscopy now", "B": "Administer misoprostol now", "C": "Transvaginal ultrasound in 4 days", "D": "Schedule dilation and evacuation", "E": "Administer methotrexate now"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 52-year-old man with chronic kidney disease presents for significant back pain that has gotten worse in the past 2 days. On exam, the patient has a moderate kyphosis with decreased range of motion of the spine secondary to pain. The patient has no neurologic deficits but is in severe pain. Lab work reveals a low normal serum calcium, slightly increased serum phosphate, and decreased serum vitamin D. What is the cause of this patient’s presentation?", "answer": "Increased bone turnover", "options": {"A": "Increased calcium absorption in the intestines", "B": "Markedly increased PTH", "C": "Drastic decrease in estrogen", "D": "Increased bone turnover", "E": "Decreased production of calcifediol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old woman brought to the emergency department because of a 1-week history of palpitations and shortness of breath. She has congestive heart failure. Current medications include furosemide, lisinopril, and atenolol. Her pulse is 124/min and irregularly irregular, and blood pressure is 110/70 mm Hg. Examination shows coarse crackles over the lower lung fields bilaterally. Treatment with digoxin is started. Five days later, an ECG shows prolongation of the PR interval. Which of the following is the most likely explanation for the observed effect of this drug?", "answer": "Increase in vagal tone", "options": {"A": "Inhibition of myocardial Na+/K+ ATPase", "B": "Inhibition of AV node L-type Ca2+ channels", "C": "Increase in vagal tone", "D": "Activation of Na+/Ca2+ exchanger", "E": "Decrease in intracellular cAMP"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the physician with pain in his right calf over the last 3 months. He mentions that the pain typically occurs after he walks approximately 100 meters and subsides after resting for 5 minutes. His medical history is significant for hypercholesterolemia, ischemic heart disease, and bilateral knee osteoarthritis. His current daily medications include aspirin and simvastatin, which he has taken for the last 2 years. The physical examination reveals diminished popliteal artery pulses on the right side. Which of the following drugs is most likely to improve this patient's symptoms?", "answer": "Cilostazol", "options": {"A": "Acetaminophen", "B": "Amlodipine", "C": "Cilostazol", "D": "Isosorbide dinitrate", "E": "Ranolazine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is studying mechanisms of urea excretion in humans. During the experiment, a healthy male volunteer receives a continuous infusion of para-aminohippurate (PAH) to achieve a PAH plasma concentration of 0.01 mg/mL. A volume of 1.0 L of urine is collected over a period of 10 hours; the urine flow rate is 1.66 mL/min. The urinary concentration of PAH is measured to be 3.74 mg/mL and his serum concentration of urea is 0.2 mg/mL. Assuming a normal filtration fraction of 20%, which of the following best estimates the filtered load of urea in this patient?", "answer": "25 mg/min", "options": {"A": "25 mg/min", "B": "620 mg/min", "C": "124 mg/min", "D": "7 mg/min", "E": "166 mg/min"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 22-year-old student presents to the college health clinic with a 1-week history of fever, sore throat, nausea, and fatigue. He could hardly get out of bed this morning. There are no pets at home. He admits to having recent unprotected sex. The vital signs include: temperature 38.3°C (101.0°F), pulse 72/min, blood pressure 118/63 mm Hg, and respiratory rate 15/min. On physical examination, he has bilateral posterior cervical lymphadenopathy, exudates over the palatine tonsil walls with soft palate petechiae, an erythematous macular rash on the trunk and arms, and mild hepatosplenomegaly. What is the most likely diagnosis?", "answer": "Infectious mononucleosis", "options": {"A": "Rubella", "B": "Acute HIV infection", "C": "Toxoplasma infection", "D": "Infectious mononucleosis", "E": "Streptococcal pharyngitis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-year-old man presents to the emergency department after an automobile accident. His vitals have significantly dropped since admission. Upon examination, his abdomen is slightly distended, the ribs on the right side are tender and appear broken, and breath sounds are diminished at the base of the right lung. An abdominal ultrasound and chest X-ray are ordered. Ultrasound shows fluid in the abdominal cavity and trauma to the liver. X-ray confirmed broken ribs and pleural effusion on the right. Based on these findings, the surgeons recommend immediate surgery. Upon entering the abdomen, an exsanguinating hemorrhage is observed. The Pringle maneuver is used to reduce bleeding. What was clamped during this maneuver?", "answer": "Hepatoduodenal ligament", "options": {"A": "Aorta above coeliac axis", "B": "Hepatic artery only", "C": "Hepatic vein only", "D": "Hepatoduodenal ligament", "E": "Splenic artery only"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old woman comes to the physician because of a 3-month history of worsening chest pain and breathlessness during exercise. She has no history of serious illness and takes no medications. Vital signs are within normal limits. Auscultation of the chest shows a murmur in the 2nd right intercostal space. A phonocardiogram of the murmur is shown. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Congenital leaflet fusion", "options": {"A": "Metastatic valvular calcification", "B": "Congenital leaflet fusion", "C": "Cystic medial necrosis", "D": "Sterile platelet thrombi formation", "E": "Viridans group streptococci infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old woman with type 2 diabetes mellitus is brought to the physician because of a 3-week history of nausea, abdominal pain, and confusion. She has a history of gastroesophageal reflux disease treated with over-the-counter antacids. She does not smoke or drink alcohol. Her only medication is metformin. Her pulse is 86/min and blood pressure is 142/85 mm Hg. Examination shows a soft abdomen. Arterial blood gas analysis on room air shows:\npH 7.46\nPCO2 44 mm Hg\nPO2 94 mm Hg\nHCO3- 30 mEq/L\nAn ECG shows a QT interval corrected for heart rate (QTc) of 0.36 seconds (N = 0.40–0.44). The serum concentration of which of the following substances is most likely to be increased in this patient?\"", "answer": "24,25-dihydroxycholecalciferol", "options": {"A": "Parathyroid hormone", "B": "Thyroid stimulating hormone", "C": "β-hydroxybutyrate", "D": "Phosphate", "E": "24,25-dihydroxycholecalciferol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-week-old male newborn is brought to the physician by his 33-year-old mother for a well-child examination. He was born at term and delivered at home because his parents wanted a natural childbirth. The mother did not receive prenatal care. She has no history of serious illness and takes no medications. According to the mother, delivery was fast and without complications. He is being exclusively breastfed. He appears healthy. He is at 35th percentile for length and at 40th percentile for weight. Physical examination shows no abnormalities. This patient is at increased risk for which of the following complications at this time?", "answer": "Hemorrhage", "options": {"A": "Hemorrhage", "B": "Gastroenteritis", "C": "Iron deficiency anemia", "D": "Diabetes mellitus", "E": "Intussusception"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 38-year-old woman comes to the physician because of a 4-month history of crampy abdominal pain, recurrent watery diarrhea, and a 2.5-kg (5.5-lb) weight loss. Her husband has noticed that after meals, her face and neck sometimes become red, and she develops shortness of breath and starts wheezing. Examination shows a grade 3/6 systolic murmur heard best at the left lower sternal border. The abdomen is soft, and there is mild tenderness to palpation with no guarding or rebound. Without treatment, this patient is at greatest risk of developing which of the following conditions?", "answer": "Pigmented dermatitis", "options": {"A": "Achlorhydria", "B": "Laryngeal edema", "C": "Pigmented dermatitis", "D": "Megaloblastic anemia", "E": "T-cell lymphoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old man presents to his primary care physician with 2 weeks of headache, palpitations, and excessive sweating. He has no past medical history and his family history is significant for clear cell renal cell carcinoma in his father as well as retinal hemangioblastomas in his older sister. On presentation his temperature is 99°F (37.2°C), blood pressure is 181/124 mmHg, pulse is 105/min, and respirations are 18/min. After administration of appropriate medications, he is taken emergently for surgical removal of a mass that was detected by abdominal computed tomography scan. A mutation on which of the following chromosomes would most likely be seen in this patient?", "answer": "3", "options": {"A": "2", "B": "3", "C": "10", "D": "11", "E": "17"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 17-year-old male presents to the emergency department after a knife fight. He initially refused to come to the hospital, but one of his wounds overlying the right antecubital fossa would not stop bleeding. Vitals include: BP 90/65, HR 115, and RR 24. He reports that he is light-headed and having visual changes. You hold direct pressure over the wound on his right arm while the rest of the team resuscitates him with crystalloid and pRBCs. After his vitals signs normalize, you note that his right arm is cool and you are unable to palpate a radial pulse. The vascular surgery team explores his right arm, finding and repairing a lacerated brachial artery. Two hours post-operatively he is complaining of 10/10 pain in his right forearm and screams out loud when you passively move his fingers. What is the most appropriate next step in management?", "answer": "Measure forearm compartment pressures", "options": {"A": "Watchful waiting", "B": "Increase his dose of hydromorphone", "C": "Compressive bandage", "D": "Measure forearm compartment pressures", "E": "Nerve block"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old woman is admitted to the intensive care unit after surgery following a motor vehicle collision. She has received a total of four units of packed red blood cells. Physical examination shows dry mucous membranes and flat neck veins. Serum studies show a creatinine of 2.1 mg/dL and urine microscopy shows granular, muddy-brown casts. A renal biopsy specimen is obtained and examined under light microscopy. Which of the following reversible cellular changes is most likely to be present?", "answer": "Swelling of the mitochondria", "options": {"A": "Vacuolization of the endoplasmatic reticulum", "B": "Rupture of lysosomes", "C": "Swelling of the mitochondria", "D": "Release of cytochrome C", "E": "Protease-induced cytoskeletal damage"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old man is brought to the emergency department 30 minutes after being involved in a motor vehicle collision. The patient was on his way to work before he lost control of his car and crashed into a tree. On arrival, the patient appears weak and lethargic. He has pain in his abdomen. His temperature is 37°C (98.6°F), pulse is 121/min, respirations are 22/min, and blood pressure is 85/60 mm Hg. He is oriented to person but not to place or time. The lungs are clear to auscultation. Cardiac examination shows tachycardia but no murmurs, rubs, or gallops. Abdominal examination shows several bruises above the umbilicus; there is diffuse abdominal tenderness. Focused assessment with sonography in trauma (FAST) is performed but the results are inconclusive. In addition to intravenous fluid resuscitation, which of the following is the most appropriate next step in management of this patient?", "answer": "Diagnostic peritoneal lavage", "options": {"A": "CT scan of the abdomen", "B": "Exploratory laparotomy", "C": "Nasogastric tube insertion", "D": "X-ray of the abdomen", "E": "Diagnostic peritoneal lavage"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 41-year-old woman presents with occasional dyspareunia and vaginal bleeding after a sexual encounter. She is in a monogamous relationship and uses oral contraception. She does not have a family history of gynecologic malignancies. She has smoked 1 pack of cigarettes per day for 15 years and drinks several glasses of wine daily. She has not received HPV vaccination. Her blood pressure is 120/70 mm Hg, heart rate is 71/min, respiratory rate is 14/min, and temperature is 36.7°C (98.1°F). A speculum examination shows a nulliparous cervix in the mid-plane of the vaginal vault with a red discoloration—approx. 1 × 2 cm in diameter. Bimanual examination revealed no apparent pathologic changes. A Papanicolaou smear is shown in the exhibit. Gene coding for which of the following proteins is most likely to be mutated in the affected cells in this case?", "answer": "p53", "options": {"A": "EGFR", "B": "p53", "C": "Myc", "D": "Btk", "E": "c-Src"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old man is brought to the emergency department because of severe right shoulder pain and inability to move the shoulder for the past 30 minutes. The pain began after being tackled while playing football. He has nausea but has not vomited. He is in no apparent distress. Examination shows the right upper extremity externally rotated and slightly abducted. Palpation of the right shoulder joint shows tenderness and an empty glenoid fossa. The right humeral head is palpated below the coracoid process. The left upper extremity is unremarkable. The radial pulses are palpable bilaterally. Which of the following is the most appropriate next step in management?", "answer": "Test sensation of the lateral shoulder", "options": {"A": "Neer impingement test", "B": "Closed reduction", "C": "Test sensation of the lateral shoulder", "D": "Drop arm test", "E": "Arthroscopic shoulder repair"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 20-year-old man is found lying unconscious on the floor of his room by his roommate. The paramedics arrive at the site and find him unresponsive with cold, clammy extremities and constricted, non-reactive pupils. He smells of alcohol and his vital signs show the following: blood pressure 110/80 mm Hg, pulse 100/min, and respiratory rate 8/min. Intravenous access is established and dextrose is administered. The roommate suggests the possibility of drug abuse by the patient. He says he has seen the patient sniff a powdery substance, and he sees the patient inject himself often but has never confronted him about it. After the initial assessment, the patient is given medication and, within 5–10 minutes of administration, the patient regains consciousness and his breathing improves. He is alert and cooperative within the next few minutes. Which of the following drugs was given to this patient to help alleviate his symptoms?\n ", "answer": "Naloxone", "options": {"A": "Ethanol", "B": "Methadone", "C": "Naloxone", "D": "Atropine", "E": "Dextrose"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 22-year-old woman presents with a complaint of low energy levels for the past 6 months. She feels as if she has no energy to do anything and has lost interest in photography, which she was previously passionate about. Feelings of hopelessness occupy her mind and she can no longer focus at work. She says she forces herself to hang out with her friends at weekends but would rather stay home. She denies any suicidal ideation. Her past medical history is significant for bulimia nervosa, which was diagnosed when she was a teen and was controlled with cognitive behavioral therapy. In addition, she has gastroesophageal reflux, which is being treated with esomeprazole. The patient has a 10-pack-year smoking history but denies any alcohol or recreational drug use. On examination, she is afebrile and vital signs are within normal limits. Her BMI is 24 kg/m2. Further physical examination is unremarkable. Which of the following aspects of this patient’s history is a contraindication to using bupropion as an antidepressant?", "answer": "History of bulimia nervosa", "options": {"A": "History of bulimia nervosa", "B": "Age of 22 years", "C": "Smoking cessation", "D": "BMI of 24 kg/m2", "E": "Esomeprazole usage"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 11-year-old girl presents to her pediatrician for evaluation of asymmetry that was detected during routine school screening. Specifically, she was asked to bend forwards while the school nurse examined her back. While leaning forward, her right scapula was found to be higher than her left scapula. She was also found to have a prominent line of spinal processes that diverged from the midline. She has been experiencing some back pain that she previously attributed to growth pains but otherwise has no symptoms. Her past medical history is significant only for mild allergies. She is sent to radiography for confirmation of the diagnosis and placed in a nighttime brace. Which of the following represents a complication of the most likely disease affecting this patient if it is left untreated?", "answer": "Restrictive lung disease", "options": {"A": "Arrhythmia", "B": "Congestive heart failure", "C": "Dislocation of the shoulders", "D": "Obstructive lung disease", "E": "Restrictive lung disease"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A group of investigators is studying the effects of aberrant protein isoforms on the pathogenesis of lung cancer. They observe that three protein isoforms are transcribed from the same 30,160 base-pair-long DNA segment on chromosome 13q. The canonical protein has a primary peptide sequence of 1186 amino acids. The second isoform has 419 amino acids and 100% amino acid sequence homology with the canonical protein. The third isoform has 232 amino acids and 92% amino acid sequence homology with the canonical protein. Which of the following is most likely responsible for the observed phenomenon?", "answer": "Alternative pre-mRNA splicing", "options": {"A": "Cytosine hypermethylation", "B": "Site-specific recombination", "C": "Alternative pre-mRNA splicing", "D": "RNA interference", "E": "Post-translational protein trimming"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 54-year-old woman comes to the physician because of paresthesias and weakness in her left leg for one year. Her symptoms have become progressively worse during this period and have led to some difficulty walking for the past month. She has had frequent headaches for the past 4 months. She has a history of hypertension and hypothyroidism. Current medications include amlodipine and levothyroxine. Her temperature is 37.3°C (99.1°F), pulse is 97/min, and blood pressure is 110/80 mm Hg. Neurologic examination shows decreased muscle strength in the left lower extremity. Deep tendon reflexes of the lower extremity are 4+ on the left and 2+ on the right side. The remainder of the examination shows no abnormalities. A complete blood count and serum concentrations of electrolytes, glucose, creatinine, and calcium are within the reference ranges. An MRI of the brain is shown. Which of the following is the most appropriate next step in management?", "answer": "Surgical resection", "options": {"A": "Surgical resection", "B": "Whole brain radiotherapy", "C": "Stereotactic brain biopsy", "D": "Stereotactic radiosurgery", "E": "Intrathecal methotrexate therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "The rapid response team is called for a 74-year-old woman on an inpatient surgical floor for supraventricular tachycardia. The patient had surgery earlier in the day for operative management of a femur fracture. The patient has a history of hypertension, atherosclerosis, type 2 diabetes, and uterine cancer status post total abdominal hysterectomy 20 years prior. With carotid massage, valsalva maneuvers, and metoprolol, the patient breaks out of her supraventricular tachycardia. Thirty minutes later, the nurse notices a decline in the patient’s status. On exam, the patient has a temperature of 98.4°F (36.9°C), blood pressure of 102/74 mmHg, pulse of 86/min, and respirations are 14/min. The patient is now dysarthric with noticeable right upper extremity weakness of 2/5 in elbow flexion and extension. All other extremities demonstrate normal strength and sensation. Which of the following most likely contributed to this decline?", "answer": "Atherosclerosis", "options": {"A": "Atherosclerosis", "B": "Diabetes", "C": "Hypertension", "D": "Long bone fracture", "E": "Malignancy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman presents with exertional dyspnea and fatigue for the past 3 months. Her past medical history is significant for multiple episodes of mild diarrhea for many years, which was earlier diagnosed as irritable bowel syndrome (IBS). She denies any current significant gastrointestinal symptoms. The patient is afebrile and vital signs are within normal limits. Physical examination reveals oral aphthous ulcers and mild conjunctival pallor. Abdominal examination is unremarkable. There is a rash present on the peripheral extremities bilaterally (see image). Laboratory findings are significant for evidence of microcytic hypochromic anemia. FOBT is negative. Which of the following is the most likely diagnosis in this patient?", "answer": "Non-tropical sprue", "options": {"A": "Small intestinal bacterial overgrowth", "B": "Non-tropical sprue", "C": "Whipple's disease", "D": "Irritable bowel disease", "E": "Tropical sprue"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old woman in graduate school comes to the physician for recurrent headaches. The headaches are unilateral, throbbing, and usually preceded by blurring of vision. The symptoms last between 12 and 48 hours and are only relieved by lying down in a dark room. She has approximately two headaches per month and has missed several days of class because of the symptoms. Physical examination is unremarkable. The patient is prescribed an abortive therapy that acts by inducing cerebral vasoconstriction. Which of the following is the most likely mechanism of action of this drug?", "answer": "Activation of 5-HT1 receptors", "options": {"A": "Inhibition of β1- and β2-adrenergic receptors", "B": "Activation of 5-HT1 receptors", "C": "Inhibition of 5-HT and NE reuptake", "D": "Inhibition of voltage-dependent Na+ channels", "E": "Inactivation of GABA degradation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old woman comes to the physician because of pain and swelling of her left leg over the past 24 hours. The pain is worse while walking and improves when resting. Seven months ago, she was diagnosed with a pulmonary embolism and was started on warfarin. Anticoagulant therapy was discontinued 1 month ago. Her sister has systemic lupus erythematosus. The patient does not smoke. She currently takes no medications. Her temperature is 37.8°C (100°F), pulse is 78/min, and blood pressure is 123/72 mm Hg. On physical examination, the left calf is diffusely erythematous, swollen, and tender. Dorsal flexion of the left foot elicits pain. Cardiopulmonary examination shows no abnormalities. On duplex ultrasonography, the left popliteal vein is not compressible. Laboratory studies show an elevated serum concentration of D-dimer and insensitivity to activated protein C. Further examination is most likely to show which of the following?", "answer": "Mutation of coagulation factor V", "options": {"A": "Antiphospholipid antibodies", "B": "Mutation of coagulation factor V", "C": "Mutation of prothrombin", "D": "Elevated levels of homocysteine", "E": "Deficiency of protein C"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 23-year-old woman visits her general practitioner with left ear pain and fever. She complains of multiple episodes of respiratory infection including bronchitis, laryngitis, and sinusitis. She was diagnosed with systemic lupus erythematosus with nephritis 8 months ago and was placed on oral prednisone. Currently, she takes prednisone daily. Her vital signs are as follows: blood pressure 130/85 mm Hg, heart rate 79/min, respiratory rate 16/min, and temperature 37.5°C (99.5°F). Her weight is 78 kg (172 lb) and height is 169 cm (5 ft 6 in). Physical examination reveals a swollen erythematous left eardrum, erythematous macular rash over sun-exposed skin, and slight calf edema. Inhibition of which of the following pathways causes diminished immune cell activation in this patient?", "answer": "NF-kß pathways", "options": {"A": "Wnt pathway", "B": "NF-kß pathways", "C": "Hippo pathway", "D": "PI3K/AKT/mTOR pathway", "E": "Notch pathway"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old girl with celiac disease is brought to the physician because of a 1-week history of generalized weakness and tingling around her mouth and in her fingertips. She also complains of abdominal cramps and nausea. In addition to following a gluten-free diet, she has been following a vegan diet for the past 2 years. Physical examination shows involuntary contractions of the muscle at the corner of her mouth and nose that are elicited by tapping on her right cheek. Her parathyroid hormone concentration is 834 pg/mL. Which of the following is the most likely underlying cause for this patient's current condition?", "answer": "Decreased intestinal absorption of ergocalciferol", "options": {"A": "Decreased conversion of 7-dehydrocholesterol to cholecalciferol", "B": "Decreased levels of renal 1α-hydroxylase", "C": "Decreased dietary intake of ergocalciferol", "D": "Decreased intestinal absorption of ergocalciferol", "E": "Autoimmune-mediated destruction of parathyroid tissue"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-year-old girl is brought to the physician because of vaginal bleeding for 2 days. There is no personal or family history of serious illness. She is at the 95th percentile for height and at the 90th percentile for weight. Examination shows enlarged breasts, and the areola and papilla have formed a secondary mound. There is coarse pubic hair that does not extend to the inner thigh. The remainder of the examination show no abnormalities. An x-ray of the left hand and wrist shows a bone age of 11 years. Her serum luteinizing hormone concentration is 0.1 mIU/mL (N < 0.2 mIU/mL). Which of the following is the most appropriate next step in management?", "answer": "GnRH stimulation test", "options": {"A": "MRI of the brain", "B": "Ultrasound of the pelvis", "C": "Reassurance and follow-up", "D": "GnRH stimulation test", "E": "Serum dehydroepiandrosterone level"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator studying disorders of hemostasis performs gene expression profiling in a family with a specific type of bleeding disorder. These patients were found to have abnormally large von Willebrand factor (vWF) multimers in their blood. Genetic analysis shows that the underlying cause is a mutation in the ADAMTS13 gene. This mutation results in a deficiency of the encoded metalloprotease, which is responsible for cleavage of vWF. Which of the following additional laboratory findings is most likely in these patients?", "answer": "Fragmented erythrocytes", "options": {"A": "Elevated haptoglobin", "B": "Urinary red blood cell casts", "C": "Elevated platelet count", "D": "Prolonged partial thromboplastin time", "E": "Fragmented erythrocytes"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 71-year-old Caucasian male presents to your office with bloody diarrhea and epigastric pain that occurs 30 minutes after eating. He has lost 15 pounds in 1 month, which he attributes to fear that the pain will return following a meal. He has a history of hyperlipidemia and myocardial infarction. Physical exam and esophagogastroduodenoscopy are unremarkable. What is the most likely cause of this patient's pain?", "answer": "Atherosclerosis", "options": {"A": "Atherosclerosis", "B": "Peptic ulcer disease", "C": "Crohn's disease", "D": "Amyloid deposition", "E": "Diverticulosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 10-year-old boy is brought to the physician with painful and enlarged lymph nodes in his right axilla that was noticed 5 days ago and has slowly grown bigger. He has had weakness, sweating, and poor appetite during this time. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. He does not take any medication. There are no similar cases in the family. On physical exam, his temperature is 38.2°C (100.8°F), the pulse is 89/min, the respiratory rate is 13/min, and the blood pressure is 110/60 mm Hg. In his right axilla, there are multiple tender, flocculent, and enlarged lymph nodes with overlying erythematous skin. There is a separate lesion on the child's forearm (see image). The lesion is painless to palpation and appears inflamed. Additional history should be obtained regarding which of the following?", "answer": "Contact with pets", "options": {"A": "Allergic rhinitis", "B": "Contact with pets", "C": "Frequent infections", "D": "Swimming", "E": "Tick bites"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old boy presents with bloody diarrhea. The patient’s mother states that he was fine this morning, but around midday, she received a call from his daycare center stating that the patient had a single bloody bowel movement. His mother states that there have been no recent changes in his diet, although they did attend a barbecue over the weekend. The patient has no recent history of fever, chills, or similar symptoms in the past. No significant past medical history. Initial laboratory studies show an elevated white blood cell (WBC) count, anemia, and a blood urea nitrogen (BUN)/creatinine ratio of 40. Stool examination shows 3+ blood but no fecal leukocytes. Which of the following tests would be diagnostic for this patient’s most likely condition?", "answer": "Stool culture in sorbitol-MacConkey medium", "options": {"A": "Gram stain for gull-winged, curved rods", "B": "Polymerase chain reaction (PCR) for DNA sequences in stool", "C": "Sigmoidoscopy", "D": "Stool culture in sorbitol-MacConkey medium", "E": "Test stool for C. difficile toxins"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old male presents with several months of fatigue, malaise, dry cough, and occasional episodes of painless hematuria. He recalls having had a sore throat several days prior to the onset of these symptoms that resolved without antibiotics. Physical exam is remarkable for diffusely coarse breath sounds bilaterally. Urinalysis reveals 2+ protein, 2+ blood, and numerous red blood cell casts are visible under light microscopy. Which is the most likely diagnosis?", "answer": "Microscopic polyangiitis", "options": {"A": "Diffuse membranous glomerulopathy", "B": "Microscopic polyangiitis", "C": "Focal segmental glomerulosclerosis", "D": "Acute poststreptococcal glomerulonephritis", "E": "Transitional cell bladder carcinoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old man comes to the physician for a wellness visit. Physical examination shows an enlarged and nodular prostate. Laboratory studies show elevated levels of prostate-specific antigen. A prostate biopsy confirms the diagnosis of prostate cancer and a radical prostatectomy is planned. This patient should be counseled on the increased risk of injury to which of the following structures?", "answer": "Cavernous nerve", "options": {"A": "Cavernous nerve", "B": "Superior vesical artery", "C": "External anal sphincter", "D": "Hypogastric nerve", "E": "Distal ureter\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An otherwise healthy 15-month-old boy is brought to the emergency department by his mother 1 hour after having a single episode of generalized tonic-clonic seizure, which stopped spontaneously after 1 minute. He was sleepy initially but is now awake and alert. His mother reports that he has had a fever and runny nose for the past 3 days. His temperature is 40.1°C (104.2°F). Physical examination shows no abnormalities. Analysis of his cerebrospinal fluid shows 3 cells/mm3, a glucose concentration of 68 mg/dL, and a protein concentration of 35 mg/dL. Administration of a drug that acts through which of the following mechanisms of action is most appropriate in this patient?", "answer": "Decreasing production of prostaglandin E2", "options": {"A": "Blocking voltage-gated Na+ channels", "B": "Increasing duration of Cl− channel opening", "C": "Decreasing production of prostaglandin E2", "D": "Inhibiting transpeptidase cross-linking", "E": "Blocking T-type Ca2+ channels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 53-year-old man is brought to the emergency department 45 minutes after the onset of a severe headache. He returned from a vacation in the mountains 4 days ago, during which he went swimming in a freshwater lake. On arrival, he is confused. His temperature is 39°C (102.2°F) and blood pressure is 105/68 mm Hg. Neurologic examination shows diffuse hyperreflexia. An MRI of the brain shows asymmetrical, bitemporal hyperintensities. A lumbar puncture is performed. Cerebrospinal fluid analysis shows:\nLeukocyte count 120/mm3\nSegmented neutrophils 10%\nLymphocytes 90%\nErythrocyte count 15/mm3\nGlucose 45 mg/dL\nOpening pressure 130 mm Hg\nProtein 75 mg/dL\nWhich of the following is the most likely causal pathogen?\"", "answer": "Herpes simplex virus", "options": {"A": "Naegleria fowleri", "B": "Herpes simplex virus", "C": "La Crosse virus", "D": "Enterovirus", "E": "Rabies virus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 10-year-old girl is brought to the physician because of itching of the vulva and anal region for the past 2 weeks. She has difficulty sleeping because of the itching. Physical examination shows excoriation marks around the vulva and perianal region. There is minor perianal erythema, but no edema or fissures. Microscopy of an adhesive tape applied to the perianal region shows multiple ova. Which of the following is the most appropriate treatment for this patient?", "answer": "Mebendazole", "options": {"A": "Mebendazole", "B": "Melarsoprol", "C": "Diethylcarbamazine", "D": "Nifurtimox", "E": "Praziquantel"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old female who recently immigrated to the United States presents to the community health clinic for episodes of disrupted vision. She is concerned because she knows several people from her hometown who went blind after having these episodes. Over the past several months, she also has developed itchy bumps on her back and lower extremities. Physical exam reveals black hyperpigmented nodules with edema and palpable lymphadenopathy, but is otherwise unremarkable without any visible discharge from the eyes. Her physician explains her underlying disease was likely transmitted by black flies. Which of the following is the most appropriate pharmacotherapy for this patient?", "answer": "Ivermectin", "options": {"A": "Diethylcarbamazine", "B": "Ivermectin", "C": "Mebendazole", "D": "Nifurtimox", "E": "Praziquantel"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 10-day-old male newborn is brought to the physician by his mother because of difficulty feeding and frequent nonbilious vomiting. His stool is soft and yellow-colored. The pregnancy was complicated by polyhydramnios and results from chorionic villus sampling showed a 47, XY, +21 karyotype. Physical examination shows mild abdominal distention and normal bowel sounds. An x-ray of the abdomen with oral contrast is shown. The most likely cause of his condition is due to a defect in which of the following embryologic processes?", "answer": "Rotation of the ventral pancreatic bud", "options": {"A": "Rotation of the ventral pancreatic bud", "B": "Foregut septation", "C": "Ganglion cell migration", "D": "Duodenal recanalization", "E": "Umbilical ring closure"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old sexually active man complains of painless growths on his penis. He is worried that he might have transmitted them to his girlfriend. Biopsy shows squamous cells with perinuclear cytoplasmic vacuolization, nuclear enlargement, and koilocytes. The doctor treats the patient by chemically ablating the warts with cryoablation. The patient encourages his girlfriend to get tested too, as he is worried she is at increased risk of developing a malignancy. Which cancer is the patient worried about?", "answer": "Cervical carcinoma", "options": {"A": "Kaposi sarcoma", "B": "Burkitt lymphoma", "C": "Hairy cell leukemia", "D": "Hepatocellular carcinoma", "E": "Cervical carcinoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 56-year-old woman is brought to the emergency department by her husband because of slurred speech and left facial droop for the past 30 minutes. During this period, she has also had numbness on the left side of her face. She has never had such an episode before. She has hypertension, hypercholesterolemia, and type 2 diabetes mellitus. Her father died of lung cancer 1 week ago. The patient has smoked one pack of cigarettes daily for 30 years. She drinks one glass of wine daily. Her current medications include metformin, sitagliptin, enalapril, and atorvastatin. She is 168 cm (5 ft 6 in) tall and weighs 86 kg (190 lb); BMI is 30.5 kg/m2. She is oriented to time, place, and person. Her temperature is 37°C (98.7°F), pulse is 97/min, and blood pressure is 140/90 mm Hg. Examination shows drooping of the left side of the face. Her speech is clear. Examination shows full muscle strength. Deep tendon reflexes are 2+ bilaterally. A finger-nose test and her gait are normal. Cardiopulmonary examination shows a right-sided carotid bruit. A complete blood count and serum concentrations of creatinine, glucose, and electrolytes are within the reference ranges. An ECG shows left ventricular hypertrophy. A noncontrast CT scan of the brain shows no abnormalities. On the way back from the CT scan, her presenting symptoms resolve. Which of the following is the most likely diagnosis?", "answer": "Transient ischemic attack", "options": {"A": "Conversion disorder", "B": "Partial seizure", "C": "Bell palsy", "D": "Transient ischemic attack", "E": "Multiple sclerosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old white woman comes to the physician because of a 6-month history of lower abdominal pain. She has also had multiple episodes of loose stools with blood during this period. She has had painful bowel movements for 1 month. Over the past year, she has had a 10-kg (22-lb) weight loss. She was treated for streptococcal pharyngitis last week. Her maternal grandfather died of colon cancer at the age of 52 years. She does not smoke. She drinks three to five beers on social occasions. She is 162 cm (5 ft 4 in) tall and weighs 52 kg (115-lb); BMI is 19.7 kg/m2. Her temperature is 37°C (98.6°F), pulse is 60/min, respirations are 13/min, and blood pressure is 110/70 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and there is tenderness to palpation of the left lower quadrant. There is no guarding or rigidity. Rectal examination shows no masses. Laboratory studies show:\nHemoglobin 10.4 g/dL\nLeukocyte count 10,800/mm3\nPlatelet count 450,000/mm3\nSerum\nNa+ 138 mEq/L\nCl- 103 mEq/L\nK+ 4.9 mEq/L\nHCO3- 22 mEq/L\nUrea nitrogen 18 mg/dL\nCreatinine 0.6 mg/dL\nAntinuclear antibodies negative\nPerinuclear antineutrophil cytoplasmic antibodies positive\nAnti-Saccharomyces cerevisiae antibodies negative\nA colonoscopy is scheduled for the next day. Which of the following findings is most likely to be present on colonoscopy of this patient?\"", "answer": "Confluent inflammation of the colonic mucosa with edema, fibrin-covered ulcers, and loss of vascular pattern", "options": {"A": "Pseudomembranes overlying regions of colonic inflammation", "B": "Patchy inflammation of mucosa with cobblestone appearance and intervening areas of normal mucosa", "C": "Confluent inflammation of the colonic mucosa with edema, fibrin-covered ulcers, and loss of vascular pattern", "D": "Normal colonic mucosa", "E": "Numerous polyps extending throughout the colon"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 44-year-old woman comes to the physician with increasingly yellow sclera and pruritus over the past 3 months. She has intermittent right-upper-quadrant pain and discomfort. She has no history of any serious illnesses and takes no medications. Her vital signs are within normal limits. Her sclera are icteric. Skin examination shows linear scratch marks on the trunk and limbs. The remainder of the physical examination is unremarkable. Laboratory studies show:\nComplete blood count\nHemoglobin 15 g/dL\nMean corpuscular volume 95 μm3\nLeukocyte count 6,000/mm3 with a normal differential\nSerum\nAlkaline phosphatase 470 U/L\nAspartate aminotransferase (AST, GOT) 38 U/L\nAlanine aminotransferase (ALT, GPT) 45 U/L\nγ-Glutamyltransferase (GGT) 83 U/L (N=5–50 U/L)\nBilirubin, total 2.7 mg/dL\nBilirubin, direct 1.4 mg/dL\nMagnetic resonance cholangiopancreatography (MRCP) shows a multifocal and diffuse beaded appearance of the intrahepatic and extrahepatic biliary ducts. Which of the following is the most appropriate diagnostic study at this time?", "answer": "Rectosigmoidoscopy", "options": {"A": "Endoscopic retrograde cholangiopancreatography (ERCP)", "B": "Liver biopsy", "C": "Rectosigmoidoscopy", "D": "Upper endoscopy", "E": "No further testing is indicated"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 62-year-old woman presents with sudden onset of vertigo, difficulty walking, sensory changes on the left side of her face and the right side of the body, and left facial drooping. Her past medical history is significant for hypertension and hypercholesterolemia. On physical examination, there is left-sided Horner’s syndrome, hypoesthesia on the left side of the face, hypoesthesia on the right side of the body, left facial paralysis,  and left-sided limb ataxia, as well as dysmetria. There is also a loss of taste sensation in the anterior 2/3 of the tongue. Based on the above findings, where is the most likely location of the vascular occlusion in this patient?", "answer": "Anterior inferior cerebellar artery (AICA)", "options": {"A": "Anterior spinal artery (ASA)", "B": "Posterior inferior cerebellar artery (PICA)", "C": "Anterior inferior cerebellar artery (AICA)", "D": "Posterior cerebral artery (PCA)", "E": "Basilar artery"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 15-year-old girl is brought to the emergency department 24 hours after the onset of a severe headache. She returned from a 1-week camping trip 3 days ago; she went spelunking and swimming in a freshwater lake during the trip. She is agitated, uncooperative, and oriented only to person. Her temperature is 38.9°C (102°F), pulse is 112/min, respirations are 20/min, and blood pressure is 100/68 mm Hg. There are several crusted insect bites on her extremities. Neurologic examination shows diffuse hyperreflexia and an extensor plantar response bilaterally. Her neck is supple without lymphadenopathy. An MRI of the brain shows asymmetrical, bitemporal hyperintensities. A lumbar puncture is performed. Cerebrospinal fluid analysis shows:\nOpening pressure 150 mm H2O\nGlucose 58 mg/dL\nProtein 108 mg/dL\nLeukocyte count 150/mm3\nSegmented neutrophils 15%\nLymphocytes 85%\nErythrocyte count 25/mm3\nWhich of the following is the most likely causal pathogen?\"", "answer": "Herpes simplex virus", "options": {"A": "West Nile virus", "B": "La Crosse virus", "C": "Tick-borne encephalitis virus", "D": "Enterovirus", "E": "Herpes simplex virus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 60-year-old man is brought to the emergency department 25 minutes after falling and hitting his left flank on a concrete block. He has severe left-sided chest pain and mild shortness of breath. He underwent a right knee replacement surgery 2 years ago. He has type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for 42 years. Current medications include metformin, sitagliptin, and a multivitamin. He appears uncomfortable. His temperature is 37.5°C (99.5°F), pulse is 102/min, respirations are 17/min, and blood pressure is 132/90 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Examination shows multiple abrasions on his left flank and trunk. The upper left chest wall is tender to palpation and bony crepitus is present. There are decreased breath sounds over both lung bases. Cardiac examination shows no murmurs, rubs, or gallops. The abdomen is soft and nontender. Focused assessment with sonography for trauma is negative. An x-ray of the chest shows nondisplaced fractures of the left 4th and 5th ribs, with clear lung fields bilaterally. Which of the following is the most appropriate next step in management?", "answer": "Adequate analgesia and conservative management", "options": {"A": "Continuous positive airway pressure", "B": "Prophylactic antibiotic therapy", "C": "Admission and surveillance in the intensive care unit", "D": "Adequate analgesia and conservative management", "E": "Internal fixation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 26-year-old woman presents to her primary care physician because she has been experiencing occasional fevers and chills for the last 3 weeks. She says that the fevers have been accompanied by abdominal pain and increased vaginal discharge. On presentation her temperature is 101.0°F (38.3°C), blood pressure is 113/75 mmHg, pulse is 105/min, and respirations are 12/min. On physical exam she is found to have tenderness over the lower abdominal quadrants, and speculum exam shows uterine inflammation as well as a retained intrauterine device. The most likely cause of this patient's symptoms should be treated with an antibiotic with which mechanism of action?", "answer": "Cell wall synthesis inhibitor", "options": {"A": "Cell wall synthesis inhibitor", "B": "DNA synthesis inhibitor", "C": "Folic acid synthesis inhibitor", "D": "Protein synthesis inhibitor", "E": "RNA synthesis inhibitor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 38-year-old man comes to the physician because of a 3-week history of right-sided knee pain. He works as a bricklayer and reports that the pain worsens when he kneels. He has no history of trauma. Examination of the right knee shows erythema, fluctuant swelling, and tenderness on palpation of the kneecap. Passive flexion of the right knee elicits pain. Which of the following structures is most likely affected in this patient?", "answer": "Prepatellar bursa", "options": {"A": "Anserine bursa", "B": "Medial meniscus", "C": "Suprapatellar bursa", "D": "Synovial membrane", "E": "Prepatellar bursa"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 38-year-old woman presents with anxiety. She says that, for as long as she can remember, she has been anxious, especially when at work or in social situations, which she has difficulty controlling. She also reports difficulty sleeping, irritability, and muscle tension. She says her symptoms have significantly limited her work and personal relationships. She has no other significant past medical history. The patient denies any history of smoking, alcohol consumption or recreational drug use. She is afebrile, and her vitals signs are within normal limits. A physical examination is unremarkable. Which of the following medications would be the most appropriate first-line treatment for this patient’s most likely diagnosis?", "answer": "Paroxetine", "options": {"A": "Propranolol", "B": "Buspirone", "C": "Paroxetine", "D": "Alprazolam", "E": "Lurasidone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old man presents to his physician with a complaint of a 4-week history of headaches that is affecting his academic performance. Over-the-counter medications do not seem to help. He also mentions that he has to raise his head each time to look at the board when taking notes. His blood pressure is 125/75 mm Hg, pulse 86/min, respiratory rate 13/min, temperature 36.8°C (98.2°F). Ophthalmic examination shows an upward gaze palsy, convergence-retraction nystagmus, and papilledema. CT scan of the head reveals a 1.5 x 1.2 cm heterogeneous mass in the epithalamus with dilated lateral and 3rd ventricles. What other finding is most likely to be associated with this patient’s condition?", "answer": "Pseudo-Argyll Robertson pupils", "options": {"A": "Medial strabismus", "B": "Sensorineural hearing loss", "C": "Pseudo-Argyll Robertson pupils", "D": "Eyes down and out", "E": "Conducting hearing loss"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 41-year-old woman presents with acute onset severe epigastric pain radiating to the back that began a few hours ago. She also complains of nausea and has vomited twice in the past hour. She denies any history of similar symptoms or trauma in the past. Past medical history is significant for diabetes type 2 and HIV infection diagnosed 6 months ago long-standing mild intermittent asthma, and generalized anxiety disorder. She takes metformin for her diabetes but does not remember the names of her HIV medications. She reports moderate social alcohol use. Her vital signs include temperature 37.6°C (99.6 °F), pulse 95/min, blood pressure 110/74 mm Hg, respiratory rate 12/min Her body mass index (BMI) is 21 kg/m2. Laboratory findings are significant for the following:\nSerum amylase: 415 U/L\nSerum lipase: 520 U/L\nA contrast CT of the abdomen reveals an edematous pancreas with peripancreatic fluid collection with a normal gallbladder. Which of the following is the most likely etiology of this patient’s condition?", "answer": "HIV medication-related", "options": {"A": "HIV medication-related", "B": "Alcohol use", "C": "Abdominal trauma", "D": "Metformin", "E": "Congenital anomaly of the pancreas"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old woman presents to the emergency department with sudden onset of painful vision loss in her left eye. The patient is otherwise healthy with a history only notable for a few emergency department presentations for numbness and tingling in her extremities with no clear etiology of her symptoms. Her temperature is 100°F (37.8°C), blood pressure is 122/83 mmHg, pulse is 100/min, respirations are 15/min, and oxygen saturation is 98% on room air. Examination of the patient's cranial nerves reveals an inability to adduct the left eye when the patient is asked to look right. Which of the following is the most appropriate treatment?", "answer": "Methylprednisolone", "options": {"A": "Estriol", "B": "Glatiramer acetate", "C": "Interferon-beta", "D": "Methylprednisolone", "E": "Rituximab"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old man is taken to the emergency department by local law enforcement after they witnessed him physically assaulting a complete stranger. The officers report that they saw his eyes “moving back and forth quickly” and noted that he was very red-faced. The patient has no significant past medical or psychiatric history. His vital signs include: temperature 38.0°C (100.4°F), blood pressure 110/70 mm Hg, pulse 102/min, and respiratory rate 25/min. On physical examination, the patient is belligerent and refuses to cooperate during the examination. Rotary nystagmus is noted. Which of the following drugs would most likely be present in a urine toxicology screen from this patient?", "answer": "Phencyclidine hydrochloride (PCP)", "options": {"A": "Lysergic acid diethylamide (LSD)", "B": "Marijuana", "C": "Methamphetamine", "D": "Cocaine", "E": "Phencyclidine hydrochloride (PCP)"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 73-year-old man presents to his primary care physician endorsing 4-5 days of decreased urinary output and mild shortness of breath. He has a complex medical history, including uncontrolled diabetes mellitus type 2, hypertension, chronic kidney disease, and end-stage emphysema. It is determined that his kidney disease has progressed to the point of needing dialysis, which his primary care physician feels should be initiated promptly. However, the patient remarks, \"I would never want dialysis. I have friends who went through it, and it sounds awful. I would rather die comfortably, even if that is soon.\" After the physician explains what dialysis is, and the risks and alternatives to the procedure the patient is able to demonstrate his understanding of dialysis including the risks, benefits and alternatives. He appears to be in no distress and demonstrates a clear understanding. After discussing the patient's wishes further, which of the following is the most appropriate response on the part of the physician?", "answer": "\"I respect that this is ultimately your decision, and will focus on making sure you are comfortable\"", "options": {"A": "\"I will obtain an ethics consultation to help with this matter\"", "B": "\"I will involve a psychiatrist to help determine your capacity to refuse this treatment\"", "C": "\"I cannot be your physician going forward if you refuse to undergo dialysis\"", "D": "\"I strongly encourage you to reconsider your decision\"", "E": "\"I respect that this is ultimately your decision, and will focus on making sure you are comfortable\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man with HIV and a recent CD4+ count of 800 presents to his PCP with fever, cough, and dyspnea. He notes that he recently lost his job as a construction worker and has not been able to afford his HAART medication. His temperature is 102.6°F (39.2°C), pulse is 75/min, respirations are 24/min, and blood pressure is 135/92 mmHg. Physical exam reveals a tachypneic patient with scattered crackles in both lungs, and labs show a CD4+ count of 145 and an elevated LDH. The chest radiography is notable for bilateral diffuse interstitial infiltrates. For definitive diagnosis, the physician obtains a sputum sample. Which stain should he use to visualize the most likely responsible organism?", "answer": "Silver stain", "options": {"A": "Ziehl-Neelsen stain", "B": "Silver stain", "C": "India ink stain", "D": "Periodic acid schiff stain", "E": "Carbol fuchsin stain"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 49-year-old woman is brought to the emergency department by her daughter because of increasing arthralgia, headache, and somnolence for the past week. She has a history of systemic lupus erythematosus without vital organ involvement. She last received low-dose glucocorticoids 2 months ago. Her temperature is 38.6 °C (101.5 °F), pulse is 80/min, respirations are 21/min, and blood pressure is 129/80 mm Hg. She is confused and disoriented. Examination shows scleral icterus and ecchymoses over the trunk and legs. Neurological examination is otherwise within normal limits. Laboratory studies show:\nHemoglobin 8.7 g/dL\nLeukocyte count 6,200/mm3\nPlatelet count 25,000/mm3\nProthrombin time 15 seconds\nPartial thromboplastin time 39 seconds\nFibrin split products negative\nSerum\nBilirubin\nTotal 4.9 mg/dL\nDirect 0.5 mg/dL\nA blood smear shows numerous fragmented red blood cells. Urinalysis shows hematuria and proteinuria. Which of the following is the most likely diagnosis?\"", "answer": "Thrombotic thrombocytopenic purpura", "options": {"A": "Immune thrombocytopenic purpura", "B": "Disseminated intravascular coagulation", "C": "Hemolytic uremic syndrome", "D": "Thrombotic thrombocytopenic purpura", "E": "Glanzmann thrombasthenia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old woman comes to the physician because of a 1-year history of intermittent buzzing in both her ears. She says she sometimes has episodes of mild dizziness which resolve spontaneously. She has a 15-year history of type 1 diabetes mellitus and episodes of low back pain. She does not smoke or drink alcohol. Current medications include insulin and aspirin. She works as a trombonist for a symphony orchestra. Her vital signs are within normal limits. On otoscopic examination, the tympanic membrane appears normal. Bone conduction is greater than air conduction in both ears. Weber test shows no lateralization. Which of the following is the most likely diagnosis?", "answer": "Otosclerosis", "options": {"A": "Drug-induced ototoxicity", "B": "Presbycusis", "C": "Endolymphatic hydrops", "D": "Otosclerosis", "E": "Diabetic otopathy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old man comes to the physician for a 2-month history of abdominal discomfort, fatigue, and increased urinary frequency, especially at night. He has also noticed that despite eating more often he has lost 14-lbs (6-kg). He has a congenital solitary kidney and a history of Hashimoto thyroiditis, for which he takes levothyroxine. He has smoked two packs of cigarettes daily for 10 years. BMI is 18 kg/m2. His temperature is 36.7°C (98.1°F), pulse is 80/min, and blood pressure is 110/60 mm Hg. Physical examination is unremarkable. Serum studies show an osmolality of 305 mOsm/L and bicarbonate of 17 mEq/L. Urinalysis shows clear-colored urine with no organisms. Which of the following is most likely to be helpful in establishing the diagnosis?", "answer": "Serum glucose", "options": {"A": "Ultrasonography of the thyroid gland", "B": "Serum glucose", "C": "Water deprivation test", "D": "Serum creatinine", "E": "Digital rectal examination"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 77-year-old man is brought to his primary care physician by his daughter. She states that lately, his speech has been incoherent. It seemed to have started a few weeks ago and has been steadily worsening. He is otherwise well; however, she notes that she has had to start him on adult diapers. The patient has a past medical history of hypertension, hyperlipidemia, and type 2 diabetes mellitus. He has been smoking 1 pack of cigarettes per day for over 40 years. His temperature is 98.9°F (37.2°C), blood pressure is 167/108 mmHg, pulse is 83/min, respirations are 12/min, and oxygen saturation is 97% on room air. Physical exam reveals a confused elderly man who does not respond coherently to questions. Cardiac and pulmonary exam is within normal limits. Inspection of the patient's scalp reveals a healing laceration which the daughter claims occurred yesterday when he fell while walking. Gait testing is significant for the patient taking short steps with reduced cadence. Which of the following findings is most likely in this patient?", "answer": "Dilated ventricles on MRI", "options": {"A": "Decreased dopamine synthesis in the substantia nigra on dopamine uptake scan", "B": "Dilated ventricles on MRI", "C": "White matter T2 hyperintensities of the cerebral cortex on MRI", "D": "Minor atrophy of the cerebral cortex on CT", "E": "Severe atrophy of the cerebral cortex on MRI"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 23-year-old man comes to the physician because of a painless swelling on the left side of his jaw for 2 months. It has been progressively increasing in size and is draining thick, foul-smelling fluid. He had a molar extracted 3 months ago. Examination shows a 4-cm, tender, erythematous mass in the left submandibular region with purulent drainage. There is submandibular lymphadenopathy. A culture of the purulent material shows catalase-negative, gram-positive filamentous rods that do not stain with carbol fuchsin. Which of the following is the most likely causal pathogen?", "answer": "Actinomyces israelii", "options": {"A": "Mucor irregularis", "B": "Acinetobacter baumannii", "C": "Actinomyces israelii", "D": "Streptococcus pneumoniae", "E": "Nocardia asteroides\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 20-month-old boy is brought to the emergency department by his parents with fever and diarrhea that have persisted for the past 2 days. He has a history of repeated bouts of diarrhea, upper respiratory tract infections, and failure to thrive. His vital signs are as follows: blood pressure 80/40 mm Hg, pulse 130/min, temperature 39.0°C (102.2°F), and respiratory rate 30/min. Blood tests are suggestive of lymphopenia. The child is diagnosed with severe combined immune deficiency after additional testing. Which of the following is the most common association with this type of immunodeficiency?", "answer": "X-linked severe combined immunodeficiency", "options": {"A": "X-linked severe combined immunodeficiency", "B": "Adenosine deaminase deficiency", "C": "Janus-associated kinase 3 (JAK3) deficiency", "D": "Reticular dysgenesis", "E": "Bare lymphocyte syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old man seeks evaluation by a physician with complaints of worsening forgetfulness and confusion for 1 year. According to his wife, he has always been in good health and is generally very happy; however, he has started to forget important things. He recently had his driving license revoked because of multiple tickets, but he cannot recall having done anything wrong. This morning, he neglected to put on his socks and was quite agitated when she pointed this out to him. He denies having a depressed mood, sleep problems, or loss of interest. He occasionally has a glass of wine with dinner and has never smoked or used recreational drugs. His medical history and family medical history are unremarkable. His pulse is 68/min, respirations are 14/min, and blood pressure is 130/84 mm Hg. Except for a mini-mental state examination (MMSE) score of 20/30, the remainder of the physical examination is unremarkable. Imaging studies, including a chest X-ray and CT of the brain, reveal no pathologic findings. An electrocardiogram (ECG) is also normal. Laboratory testing showed the following:\nSerum glucose (fasting) 76 mg/dL\nSerum electrolytes:  \nSodium 140 mEq/L\nPotassium 4.1 mEq/L\nChloride 100 mEq/L\nSerum creatinine 0.9 mg/dL\nBlood urea nitrogen 11 mg/dL\nCholesterol, total: 180 mg/dL\nHDL-cholesterol 45 mg/dL\nLDL-cholesterol 75 mg/dL\nTriglycerides 135 mg/dL\nHemoglobin (Hb%) 16 g/dL\nMean corpuscular volume (MCV)  85 fL\nReticulocyte count 0.9%\nErythrocyte count 5 million/mm³\nThyroid-stimulating hormone 3.5 µU/mL\nUrinalysis \nGlucose Negative\nKetones Negative\nLeucocytes Negative\nNitrite Negative\nRBCs Negative\nCasts Negative\nWhich of the following is the most likely diagnosis?", "answer": "Alzheimer’s dementia", "options": {"A": "Alzheimer’s dementia", "B": "Creutzfeldt-Jakob disease", "C": "Lewy body dementia", "D": "Parkinson’s disease", "E": "Vascular dementia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 26-year-old woman is brought to the emergency department after a suicide attempt. Her mother found her next to an empty bottle of acetaminophen in the bathroom. The patient reports that she ingested about twenty-five 500 mg pills. She took the pills 1 hour prior to arrival to the emergency department. She has a history of major depressive disorder. She does not smoke or use illicit drugs. Current medications include fluoxetine. She is oriented to person, place, and time. Vital signs are within normal limits. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12.5 g/dL\nLeukocyte count 8,000/mm3\nPlatelet count 150,000/mm3\nSerum\nProthrombin time 10.5 sec (INR=1.0)\nNa+ 141 mEq/L\nK+ 4.2 mEq/L\nCl- 101 mEq/L\nHCO3- 25 mEq/L\nUrea nitrogen 10 g/dL\nCreatinine 0.5 g/dL\nCa2+ 8.8 mg/dL\nTotal bilirubin 0.4 mg/dL\nAST 22 U/L\nALT 25 U/L\nAlkaline phosphatase 62 U/L\nWhich of the following is the most appropriate next step in management?\"", "answer": "Administer activated charcoal", "options": {"A": "Administer N-acetylcysteine", "B": "Administer activated charcoal", "C": "Admit for observation", "D": "List for liver transplant", "E": "Perform liver biopsy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old woman is brought to the physician by her husband because she cries frequently and refuses to get out of bed. Over the past 3 weeks, she has been feeling sad and tired most of the time. She has difficulty staying asleep at night and often wakes up early in the morning. After losing her job as a waitress 1 month ago, she has been feeling guilty for not contributing to the household income anymore. She would like to find a new position but is unable to decide “what to do with her life”. She was diagnosed with anorexia nervosa at age 18 and has gone to psychotherapy several times since then. Her weight had been stable for the past 5 years; however, within the past 3 weeks, she has had a 2.8-kg (6.2-lb) weight loss. She would like to regain some weight. She is 160 cm (5 ft 3 in) tall and currently weighs 47 kg (104 lb); BMI is 18.4 kg/m2. Her temperature is 36.3°C (97.3°F), pulse is 58/min, and blood pressure is 110/60 mm Hg. Physical examination shows no abnormalities. Mental status examination shows a depressed mood and flat affect. There is no evidence of suicidal ideation. Which of the following drugs is most likely to address both this patient's mood disorder and her desire to gain weight?", "answer": "Mirtazapine", "options": {"A": "Lithium", "B": "Mirtazapine", "C": "Olanzapine", "D": "Topiramate", "E": "Phenelzine\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-month-old girl with a previous diagnosis of DiGeorge syndrome is brought to the emergency department with her parents following a seizure. Her mother states that the baby had been inconsolable all day and refused to feed. She was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines. Upon arrival to the hospital her heart rate is 120/min, respiratory rate is 40/min, and temperature of 37.0°C (98.6°F). On examination, she is afebrile and somnolent and her fontanelles are open and soft. While attempting to take her blood pressure, the patient’s arm and hand flex sharply and do not relax until the cuff is released. A light tap on the cheek results in an atypical facial muscle twitch. A CMP and CBC are drawn and sent for analysis. Which of the following is the most likely cause?", "answer": "Hypocalcemia", "options": {"A": "Hypernatremia", "B": "Hypocalcemia", "C": "Meningitis", "D": "High fever", "E": "Tetanus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2900-g (6.4-lb) male newborn is delivered at term to a 29-year-old primigravid woman. His mother had no routine prenatal care. She reports that the pregnancy was uncomplicated apart from a 2-week episode of a low-grade fever and swollen lymph nodes during her early pregnancy. She has avoided all routine vaccinations because she believes that “natural immunity is better.” The newborn is at the 35th percentile for height, 15th percentile for weight, and 3rd percentile for head circumference. Fundoscopic examination shows inflammation of the choroid and the retina in both eyes. A CT scan of the head shows diffuse intracranial calcifications and mild ventriculomegaly. Prenatal avoidance of which of the following would have most likely prevented this newborn's condition?", "answer": "Undercooked pork", "options": {"A": "Exposure to unvaccinated children", "B": "Undercooked pork", "C": "Unprotected sexual intercourse", "D": "Mosquito bites", "E": "Raw cow milk products"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 6-year-old girl is brought to the physician for a well-child examination. There is no personal or family history of serious illness. She is at the 90th percentile for height and weight. Vital signs are within normal limits. Examination shows enlarged breast buds that extend beyond the areola. There is coarse pubic hair that does not extend onto the inner thigh. The remainder of the examination show no abnormalities. An x-ray of the left hand shows a bone age of 10 years. Following GnRH agonist stimulation, serum luteinizing hormone levels increase to twice the median. Which of the following is the most appropriate next best step in management?", "answer": "MRI of the brain", "options": {"A": "Leuprolide therapy", "B": "Reassurance and follow-up", "C": "MRI of the brain", "D": "Ultrasound of the pelvis", "E": "Anastrozole therapy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old female presents to the emergency room with dry cough and malaise. She has no other complaints. She has a past medical history of a meningioma status post resection complicated by hemiplegia and has been managed with dexamethasone for several months. Her vital signs are T 100.4 F (38 C), O2 93% on room air, RR 20, BP 115/75 mmHg. Physical examination is notable for crackles bilaterally. A chest radiograph is obtained (Image A). The patient is admitted and initially treated guideline-compliant antibiotics for community-acquired pneumonia. Unfortunately, her respiratory function deteriorates. An arterial blood gas is drawn. On room air at sea level, PaO2 is 71 mmHg and PaCO2 is 34 mmHg. Induced sputum samples reveal organisms on methenamine silver stain. What is the best treatment strategy for this patient?", "answer": "Trimethoprim-sulfamethoxazole + steroids", "options": {"A": "Trimethoprim-sulfamethoxazole", "B": "Metronidazole", "C": "Trimethoprim-sulfamethoxazole + steroids", "D": "Piperacillin-tazobactam", "E": "Piperacillin-tazobactam + steroids"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "You are called to see a chemotherapy patient who is complaining of severe nausea. This patient is a 52-year-old male with acute lymphoblastic leukemia (ALL) who began his first cycle of chemotherapy 2 days ago. Which of the following structures is involved in the pathway responsible for this patient's nausea?", "answer": "Medulla oblongata", "options": {"A": "Medulla oblongata", "B": "Medial geniculate nucleus", "C": "Lateral geniculate nucleus", "D": "Posterior hypothalamus", "E": "Ventral posterolateral nucleus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old tow truck driver presents to the emergency room in the middle of the night complaining of sudden onset right ankle pain. He states that the pain came on suddenly and woke him up from sleep. It was so severe that he had to call an ambulance to bring him to the hospital since he was unable to drive. He has a history of hypertension and types 2 diabetes mellitus, for which he takes lisinopril and methotrexate. He has no other medical problems. The family history is notable for hypertension on his father’s side. The vital signs include: blood pressure 126/86 mm Hg, heart rate 84/min, respiratory rate 14/min, and temperature 37.2°C (99.0°F). On physical exam, the patient’s right ankle is swollen, erythematous, exquisitely painful, and warm to the touch. An arthrocentesis is performed and shows negatively birefringent crystals on polarized light. Which of the following is the best choice for treating this patient’s pain?", "answer": "Administer indomethacin", "options": {"A": "Administer allopurinol", "B": "Administer probenecid", "C": "Administer colchicine", "D": "Administer indomethacin", "E": "Administer febuxostat"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 63-year-old man with a history of diabetes mellitus presents with complaints of fatigue. He lives alone and has not seen a doctor in 10 years. He does not exercise, eats a poor diet, and drinks 1-2 beers per day. He does not smoke. He has never had a colonoscopy. Labs show a hemoglobin of 8.9 g/dL (normal 13.5 - 17.5), mean corpuscular volume of 70 fL (normal 80-100), serum ferritin of 400 ng/mL (normal 15-200), TIBC 200 micrograms/dL (normal 250-420), and serum iron 50 micrograms/dL (normal 65-150). Which of the following is the cause of his abnormal lab values?", "answer": "Chronic inflammation", "options": {"A": "Vitamin deficiency", "B": "Mineral deficiency", "C": "Mineral excess", "D": "Chronic inflammation", "E": "Occult bleeding"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old woman, gravida 3, para 3, comes to the physician for a follow-up examination. She gave birth to her third child 8 months ago and now wishes to start a contraception method. Prior to her most recent pregnancy, she used a combined estrogen-progestin pill. Which of the following aspects of her history would be a contraindication for restarting an oral contraceptive pill?", "answer": "She smokes 1 pack of cigarettes daily", "options": {"A": "Her hemoglobin A1c is 8.6%", "B": "She smokes 1 pack of cigarettes daily", "C": "She has recurrent migraine headaches without aura", "D": "She has a history of cervical dysplasia", "E": "Her infant is still breastfeeding"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old boy is brought to the physician by his mother because of 4 months of strange behavior. She says that during this period, he has had episodic mood swings. She has sometimes found him in his room “seemingly drunk” and with slurred speech. These episodes usually last for approximately 15 minutes, after which he becomes irritable. He has had decreased appetite, and his eyes occasionally appear red. He has trouble keeping up with his schoolwork, and his grades have worsened. Physical examination shows an eczematous rash between the upper lip and nostrils. Neurologic examination shows a delay in performing alternating palm movements. Use of which of the following is the most likely cause of this patient's condition?", "answer": "Inhalants", "options": {"A": "Inhalants", "B": "Alcohol", "C": "Phencyclidine", "D": "Cocaine", "E": "Marijuana"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 40-year-old woman comes to the physician because of a small lump on the right side of her neck that she noticed while putting lotion on 1 week ago. She does not have any weight change, palpitations, or altered bowel habits. There is no family history of serious illness. Menses occur at regular 30-day intervals and lasts for 4 days. She appears well. Her temperature is 37°C (98.6° F), pulse is 88/min, and blood pressure is 116/74 mm Hg. Examination shows a small swelling on the right side of the neck that moves with swallowing. There is no lymphadenopathy. Ultrasound of the neck shows a 0.9-cm (0.35-in) right lobe thyroid mass with microcalcifications and irregular margins. Which of the following is the most appropriate next step in diagnosis?", "answer": "Thyroid-stimulating hormone level", "options": {"A": "Fine-needle aspiration biopsy of the swelling", "B": "Open biopsy", "C": "Thyroid scintigraphy", "D": "Thyroid-stimulating hormone level", "E": "CT of the neck"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old woman, gravida 2, para 1, at 26 weeks' gestation comes to the emergency department because of a gush of clear fluid from her vagina that occurred 1 hour prior. She reports painful pelvic cramping at regular 5-minute intervals. She has missed most of her prenatal care visit because of financial problems from her recent divorce. Her first child was delivered vaginally at 27 weeks' gestation due to spontaneous preterm labor. She has smoked one pack of cigarettes daily for 15 years but has reduced her intake to 2–3 cigarettes per day since finding out she was pregnant. She continues to use cocaine once a week. Vital signs are within normal limits. Sterile speculum examination shows fluid pooling in the vagina, and nitrazine paper testing confirms the presence of amniotic fluid. Which of the following puts her at highest risk of preterm delivery?", "answer": "History of spontaneous preterm birth\n\"", "options": {"A": "Low socioeconomic status", "B": "Smoking during pregnancy", "C": "Substance abuse during pregnancy", "D": "Advanced maternal age", "E": "History of spontaneous preterm birth\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 52-year-old woman comes to the physician because of a 3-week history of pain in her right knee. The pain is worse at the end of the day and when she walks. She says that it has become difficult for her to walk up the flight of stairs to reach her apartment. She has hypertension and psoriasis. Her sister has rheumatoid arthritis. She drinks 2–3 beers daily. Current medications include hydrochlorothiazide, topical betamethasone, and a multivitamin. She is 160 cm (5 ft 3 in) tall and weighs 92 kg (202 lb); BMI is 36 kg/m2. She appears anxious. Her temperature is 37°C (98.6°F), pulse is 87/min, and blood pressure is 135/83 mm Hg. Cardiopulmonary examinations shows no abnormalities. There are several scaly plaques over the patient's upper and lower extremities. The right knee is not tender nor erythematous; range of motion is limited. Crepitus is heard on flexion and extension of the knee. Her hemoglobin concentration is 12.6 g/dL, leukocyte count is 9,000/mm3, and erythrocyte sedimentation rate is 16 mm/h. An x-ray of the right knee is shown. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Weight loss program", "options": {"A": "Intraarticular glucocorticoid injections", "B": "Weight loss program", "C": "Total joint replacement", "D": "Methotrexate therapy", "E": "Colchicine therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old female with no past medical history is found to have an abnormal cardiovascular exam during routine physical examination at her pediatrician’s office. All other components of her physical exam are normal. During evaluation for potential causes for her abnormal exam, an echocardiogram with doppler is done that shows flow between the atria. Which of the following would would have most likely been auscultated as a result of the pathology on her echocardiogram?", "answer": "Splitting of S2 in inspiration and expiration", "options": {"A": "Increased splitting of S1 with inspiration", "B": "Decreased splitting of S1 with inspiration", "C": "Normal splitting of S2", "D": "Increased splitting of S2 with inspiration", "E": "Splitting of S2 in inspiration and expiration"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "As part of a clinical research study, microscopic analysis of tissues obtained from surgical specimens is performed. Some of these tissues have microscopic findings of an increase in the size of numerous cells within the tissue with an increase in the amount of cytoplasm, but the nuclei are uniform in size. Which of the following processes shows such microscopic findings?", "answer": "Uterine myometrium in pregnancy", "options": {"A": "Uterine myometrium in pregnancy", "B": "Liver following partial resection", "C": "Ovaries following menopause", "D": "Cervix with chronic inflammation", "E": "Female breasts at puberty"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old man comes to the physician because of a 3-year history of urinating up to 20 times each day. He has not had any dysuria and nocturia. He has been evaluated by several urologists but has not received a specific diagnosis despite extensive diagnostic testing. Various pharmacologic treatments have not improved his symptoms. He quit his job 1 year ago and stopped attending social events because his frequent urination has been disruptive. He spends most of his time at the library trying to learn what could be causing his symptoms. He would like to undergo a CT scan of his entire body to evaluate for cancer. Physical examination and laboratory studies show no abnormalities. Mental status examination shows a depressed mood and constricted affect. There is no evidence of suicidal ideation. Which of the following is the most likely explanation for this patient's symptoms?", "answer": "Somatic symptom disorder", "options": {"A": "Malingering", "B": "Atypical depression", "C": "Somatic symptom disorder", "D": "Adjustment disorder", "E": "Recurrent urinary tract infections"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old woman is brought to the emergency department of a busy suburban hospital because of a 1-week history of nausea and vomiting. She also has had intermittent fevers and headaches during the past 5 weeks. She does not have a stiff neck or sensitivity to light. She appears tired. Her temperature is 37°C (98.6°F), pulse is 70/min, respirations are 15/min, and blood pressure is 135/85 mm Hg. She is alert and oriented to person, place, and time. Examination shows no abnormalities. A lumbar puncture is performed, and cerebrospinal fluid (CSF) is collected for analysis. On the way to the laboratory, the physician loses the CSF specimens. The physician decides that a repeat lumbar puncture should be performed. Before giving consent for the second procedure, the patient asks what the results are from the specimens obtained earlier. Which of the following responses by the physician is the most appropriate?", "answer": "\"\"\"I was unable to obtain results from the earlier tests because I misplaced the specimens. I sincerely apologize for the mistake.\"\"\"", "options": {"A": "\"\"\"I sincerely apologize; I misplaced the specimens. Thankfully, this is not a big issue because I can easily obtain more fluid.\"\"\"", "B": "\"\"\"I was unable to obtain results from the earlier tests because I misplaced the specimens. I sincerely apologize for the mistake.\"\"\"", "C": "\"\"\"I was not able to get the answers we needed from the first set of tests, so we need to repeat them.\"\"\"", "D": "\"\"\"Unfortunately, I was not able to get enough fluid in the specimens to perform the tests.\"\"\"", "E": "\"\"\"I sincerely apologize; the lab seems to have lost the specimens I obtained earlier.\"\"\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 74-year-old woman with a past medical history of hypertension, peripheral artery disease, and migraine headaches presents to the emergency department with a two hour history of severe abdominal pain. The patient cannot recall any similar episodes, although she notes occasional abdominal discomfort after eating. She describes the pain as sharp periumbilcal pain. She denies recent illness, fever, chills, nausea, vomiting, or diarrhea. Her last normal bowel movement was yesterday evening. Her temperature is 37.1°C (98.8°F), pulse is 110/min, blood pressure is 140/80 mmHg, and respirations are 20/min. On exam, the patient is grimacing and appears to be in significant discomfort. Heart and lung exams are within normal limits. The patient’s abdomen is soft and non-distended with diffuse periumbilical pain on palpation. There is no rebound tenderness or guarding, and bowel sounds are present. The rest of the exam is unremarkable. Labs in the emergency room show:\n\nSerum:\nNa+: 144 mEq/L\nCl-: 105 mEq/L\nK+: 3.7 mEq/L\nHCO3-: 20 mEq/L\nBUN: 15 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.2 mg/dL\nCa2+: 10.7 mg/dL\nPhosphorus: 5.2 mg/dL\nLactate: 7.0 mmol/L\nAmylase: 240 U/L\n\nHemoglobin: 13.4 g/dL\nHematocrit: 35%\nLeukocyte count: 12,100 cells/mm^3 with normal differential\nPlatelet count: 405,000/mm^3\n\nWhat is the next best step in diagnosis?", "answer": "CT angiography", "options": {"A": "D-dimer level", "B": "Plain abdominal radiograph", "C": "Exploratory laparotomy", "D": "CT angiography", "E": "Abdominal duplex ultrasound"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 39-year-old man presents to his primary care physician with a 10-hour history of severe diarrhea. He says that he was recently at a company picnic and after returning home he began to experience severe watery diarrhea. He says that the diarrhea was accompanied by nausea and abdominal pain. His physician informs him that he was likely infected by a lactose-fermenting, gram-negative organism. Which of the following changes would be seen in a cell that was affected by the heat stable toxin produced by this organism?", "answer": "Increased cyclic guanosine monophosphate", "options": {"A": "Decreased cyclic adenosine monophosphate", "B": "Decreased cyclic guanosine monophosphate", "C": "Increased calcium", "D": "Increased cyclic adenosine monophosphate", "E": "Increased cyclic guanosine monophosphate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An investigator is studying the structure of the amino-terminal of the Huntingtin protein using x-ray crystallography. The terminal region is determined to have an α-helix conformation. Which of the following forces is most likely responsible for maintaining this conformation?", "answer": "Hydrogen bonds", "options": {"A": "Hydrophobic interactions", "B": "Disulfide bonds", "C": "Peptide bonds", "D": "Electrostatic side chain attraction", "E": "Hydrogen bonds"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man with a past medical history of anterior myocardial infarction, peripheral arterial disease, and known patent foramen ovale presents to the emergency department after being found down from a fall on the sidewalk in the middle of winter. He states that his right leg feels numb and painful at the same time. He insists that he did not slip on ice or snow, yet fell suddenly. He is taking aspirin, simvastatin, and cilastazol. Vital signs show T 98.0 F, BP 100/60, HR 100, RR 18. His pulse is irregularly irregular. His right leg appears pale with no dorsalis pedis and posterior tibial pulses compared to 2+ pulses on the left. He cannot discern soft or sharp touch in his right leg. Which intervention will most likely improve the viability of this patient's right leg?", "answer": "Catheter-based thrombectomy / thrombolysis", "options": {"A": "Percutaneous transluminal stent implantation", "B": "Rivaroxaban", "C": "Warfarin", "D": "Catheter-based thrombectomy / thrombolysis", "E": "Heparin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 3-year-old boy is brought to the physician by his parents for the evaluation of easy bruising for several months. Minor trauma also causes scratches that bleed. Two months ago, a fall from his bed caused a large forehead hematoma and a left elbow laceration. He sometimes does not eat because of pain while chewing. Vital signs are within normal limits. Examination shows that the skin can be stretched further than normal and is fragile. Range of motion of the joints is slightly increased. There is tenderness to palpation of the temporomandibular joints bilaterally. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Defective type V collagen", "options": {"A": "Impaired copper absorption", "B": "Factor VIII deficiency", "C": "Defective type III collagen", "D": "Defective type V collagen", "E": "Defective type I collagen\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 64-year-old male presents to the emergency room with difficulty breathing. He recently returned to the USA following a trip to Singapore. He reports that he developed pleuritic chest pain, shortness of breath, and a cough. His temperature is 99°F (37.2°C), blood pressure is 140/85 mmHg, pulse is 110/min, and respirations are 24/min. A spiral CT reveals a pulmonary embolus in the right segmental pulmonary artery. Results from a complete blood count are all within normal limits. He is admitted and started on unfractionated heparin. Four days later, the patient develops unprovoked epistaxis. A complete blood count reveals the following:\n\nLeukocyte count: 7,000/mm^3\nHemoglobin: 14 g/dl\nHematocrit: 44%\nPlatelet count 40,000/mm^3\n\nWhat is the underlying pathogenesis of this patient’s condition?", "answer": "Autoantibodies directed against platelet factor 4", "options": {"A": "Loss of vitamin K-dependent clotting factors", "B": "Autoantibodies directed against platelet factor 4", "C": "Medication-mediated platelet aggregation", "D": "Autoantibodies directed against GPIIb/IIIa", "E": "ADAMTS13 deficiency"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An autopsy is performed on a 39-year-old man 5 days after he was found pulseless at his apartment by his neighbor. Examination of the brain shows liquefactive necrosis in the distribution of the right middle cerebral artery with surrounding edema. Immunophenotyping of a sample of the affected brain tissue shows numerous cells that express CD40 on their surface. On further histopathological evaluation, the morphology of these cells is not readily discernible with Nissl stain. These histological findings are most consistent with which of the following cell types?", "answer": "Microglia", "options": {"A": "Radial glial cells", "B": "Microglia", "C": "Astrocytes", "D": "Oligodendrocytes", "E": "Neurons"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A recent study shows that almost 40% of the antibiotics prescribed by primary care physicians in the ambulatory setting are for patients with a clinical presentation consistent with a viral acute respiratory tract infection. Recent evidence suggests that the implementation of a set of interventions may reduce such inappropriate prescribing. Which of the following strategies, amongst others, is most likely to achieve this goal?", "answer": "Local peer comparison", "options": {"A": "C-reactive protein (CRP) testing", "B": "Delayed antibiotic use", "C": "Local peer comparison", "D": "Procalcitonin testing", "E": "Testing for non-antibiotic-appropriate diagnoses"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 14-year-old boy is brought to the physician for generalized fatigue and mild shortness of breath on exertion for 3 months. He has a history of recurrent patellar dislocations. He is at the 99th percentile for height and at the 30th percentile for weight. His temperature is 37°C (98.6°F), pulse is 99/min, and blood pressure is 140/50 mm Hg. Examination shows scoliosis, a protruding breast bone, thin extremities, and flat feet. Ocular examination shows upwards displacement of bilateral lenses. A grade 3/6 early diastolic murmur is heard along the left sternal border. Further evaluation of this patient is most likely to show which of the following?", "answer": "Water hammer pulse", "options": {"A": "Paradoxical splitting of S2", "B": "Pulsus paradoxus", "C": "Fixed splitting of S2", "D": "Water hammer pulse", "E": "Radio-femoral pulse delay"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year old girl is brought to the physician by her mother because menarche has not yet occurred. She is at the 3rd percentile for height. Examination of a buccal mucosal scraping shows several cells with a single dark body attached to the nuclear membrane. Karyotyping of a neutrophil shows 45 chromosomes. Which of the following is the most likely underlying cause of this patient's cytogenetic abnormality?", "answer": "Postzygotic mitotic error", "options": {"A": "Uniparental isodisomy", "B": "Postzygotic mitotic error", "C": "Robertsonian translocation", "D": "Nondisjunction during meiosis I", "E": "Reciprocal translocation\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-month-old boy is brought to the emergency department by his mother after a seizure at home. The mother is not sure how long the seizure lasted, but says that the boy was unresponsive and had episodes of stiffness and jerking of his extremities throughout the episode. The mother states that the boy has not seemed himself for the past several weeks and has been fussy with feeds. He does not sleep through the night. He has not had any recent infections or sick contacts.\n\nOn exam, the boy is lethargic. His temperature is 99.5°F (37.5°C), blood pressure is 70/40 mmHg, and pulse is 120/min. He has no murmurs and his lungs are clear to auscultation bilaterally. His abdomen appears protuberant, and his liver span is measured at 4.5 cm below the costal margin. Additionally, the boy has abnormally enlarged cheeks. A finger stick in the ED reveals a blood glucose level of 35 mg/dL. What would this patient’s response to a fasting-state glucagon stimulation test most likely be, and what enzyme defect does he have?", "answer": "No change in plasma glucose; glucose-6-phosphatase", "options": {"A": "Rise in plasma glucose; glycogen debranching enzyme", "B": "Rise in plasma glucose; glucose-6-phosphatase", "C": "Rise in plasma glucose; alpha-1,4-glucosidase", "D": "No change in plasma glucose; glycogen debranching enzyme", "E": "No change in plasma glucose; glucose-6-phosphatase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-year-old boy is brought to the emergency department for evaluation of a fever for 1 day. The mother reports that he has had severe pain in his lower extremities and difficulty eating since yesterday. He has not had a cough, nausea, or vomiting. He was born at term and has been healthy. His immunizations are up-to-date. He appears irritable. His temperature is 38.5°C (101.3°F). Examination shows several flesh-colored, tender papules over the trunk, knees, palms, and soles. There are multiple 2-mm, reddish macules on the hard palate. The remainder of the examination shows no abnormalities. Which of the following is the most likely causal organism of this patient's symptoms?", "answer": "Coxsackie A virus", "options": {"A": "Human herpesvirus 6", "B": "Rubella virus", "C": "Herpes simplex virus 1", "D": "Coxsackie A virus", "E": "Measles virus"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "After the administration of an erroneous dose of intravenous phenytoin for recurrent seizures, a 9-year-old girl is resuscitated because of bradycardia and asystole. Later, the patient is taken to the critical care unit and placed on mechanical ventilation. Neurologic consultation shows hypoxic brain injury. To reduce the incidence of similar events, which of the following is the most appropriate next step in management?", "answer": "Root cause analysis", "options": {"A": "Closed-loop communication", "B": "Computerized physician order entry", "C": "Root cause analysis", "D": "Structured handovers", "E": "Two patient identifiers"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70-year-old chronic smoker presents to the emergency department with a sudden onset of left-sided weakness. The past medical history is insignificant except for hypertension, for which he has been taking medications regularly. The vital signs include: blood pressure 165/110 mm Hg, pulse rate 78/min, respiratory rate 18/min, and temperature 36.1°C (97°F). The neurologic examination shows ⅗ muscle strength in the left upper and lower limbs. An occlusion of a branch of the right middle cerebral artery is suspected because the CT fails to show signs of hemorrhage. The HbA1C is 11%. Which of the following blood lipid components is the most important contributing factor leading to his condition?", "answer": "Oxidized low-density lipoprotein (ox-LDL)", "options": {"A": "Very low-density lipoprotein (VLDL)", "B": "Chylomicron", "C": "Oxidized low-density lipoprotein (ox-LDL)", "D": "Lipoprotein lipase (LPL)", "E": "High-density lipoprotein (HDL)-cholesterol"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 80-year-old man comes to the office for evaluation of anemia. His medical history is relevant for end-stage renal disease and aortic stenosis. When questioned about his bowel movements, the patient mentions that he has occasional episodes of loose, black, tarry stools. His heart rate is 78/min, respiratory rate is 17/min, temperature is 36.6°C (97.8°F), and blood pressure is 80/60 mm Hg. Physical examination shows pale skin and conjunctiva and orthostasis upon standing. A complete blood count shows his hemoglobin is 8.7 g/dL, hematocrit is 27%, and mean corpuscular volume is 76 μm3. A colonoscopy is obtained. Which of the following is the most likely cause of this patient’s current condition?", "answer": "Angiodysplasia", "options": {"A": "Angiodysplasia", "B": "Colorectal cancer", "C": "Ischemic colitis", "D": "Portal hypertension", "E": "Colonic polyps"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 69-year-old man with history of coronary artery disease necessitating angioplasty and stent placement presents to the ED due to fever, chills, and productive cough for one day. He is started on levofloxacin and admitted because of his comorbidity and observed tachypnea of 35 breaths per minute. He is continued on his home medications including aspirin, clopidogrel, metoprolol, and lisinopril. He cannot ambulate as frequently as he would like due to his immediate dependence on oxygen. What intervention should be provided for deep venous thrombosis prophylaxis in this patient while hospitalized?", "answer": "Low molecular weight heparin", "options": {"A": "Aspirin is sufficient; hold clopidogrel", "B": "Clopidogrel is sufficient; hold aspirin", "C": "Aspirin and clopidogrel are sufficient", "D": "Warfarin", "E": "Low molecular weight heparin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old woman presents to the physician with complaints of unexplained weight loss of approximately 5 kg (11.02 lb) over the last 6 months. Her other complaints include repeated stomatitis and diarrhea for 1 year. She was diagnosed with diabetes mellitus 1 year ago. Her temperature is 36.9°C (98.4°F), heart rate is 84/min, respiratory rate is 16/min, and blood pressure is 126/82 mm Hg. Physical examination reveals multiple, confluent, erythematous papules, plaques and bullous lesions over the extremities, the perioral region, and the perigenital region. An oral examination shows angular cheilitis, glossitis, and stomatitis. Which test is most likely to yield an accurate diagnosis for this patient?", "answer": "Serum glucagon", "options": {"A": "Serum gastrin", "B": "Serum glucagon", "C": "Serum insulin", "D": "Serum prolactin", "E": "Serum vasoactive intestinal polypeptide"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the physician because of increasing swelling of the legs and face over the past 2 months. During this time, he has experienced fatigue and weight loss. He has no history of any serious illness and takes no medications. Vital signs are within normal range. On physical examination, both lower limbs show significant pitting edema extending above the knees. A photograph of the patient’s facial features is shown. His urinary protein is 3 g/24 h. Serum and urine electrophoresis shows monoclonal light chains. Skeletal survey shows no osteolytic lesions. Without treatment, which of the following is the most likely clinical course for this patient?", "answer": "Death within 1–2 years", "options": {"A": "Death within 1–2 years", "B": "Hyperviscosity syndrome", "C": "Long-term survival without serious complications", "D": "Richter’s transformation", "E": "Transformation into multiple myeloma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A six-month-old infant presents with chronic, persistent diarrhea, oral thrush, and a severe diaper rash. The infant was treated four weeks ago for an upper respiratory and ear infection. A family history is significant for a consanguineous relationship between the mother and father. Physical examination demonstrates the absence of palpable lymph nodes. Accumulation of which of the following would lead to this disease phenotype?", "answer": "Deoxyadenosine", "options": {"A": "Deoxyadenosine", "B": "Phenylalanine", "C": "Galactitol", "D": "Ceramide trihexoside", "E": "Sphingomyelin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 19-year-old Caucasian college student is home for the summer. Her parents note that she has lost quite a bit of weight. The daughter explains that the weight loss was unintentional. She also notes an increase in thirst, hunger, and urine output. Her parents decide to take her to their family physician, who suspects finding which of the following?", "answer": "Elevated ketone levels", "options": {"A": "Evidence of amyloid deposition in pancreatic islets", "B": "High T4 and T3 levels", "C": "Elevated ketone levels", "D": "Hypoglycemia", "E": "Hyperinsulinemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 84-year-old woman with Alzheimer's disease is brought to the physician by her son for a follow-up examination. The patient lives with her son, who is her primary caregiver. He reports that it is becoming gradually more difficult to care for her. She occasionally has tantrums and there are times when she does not recognize him. She sleeps 6–8 hours throughout the day and is increasingly agitated and confused at night. When the phone, television, or oven beeps she thinks she is at the dentist's office and becomes very anxious. She eats 2–3 meals a day and has a good appetite. She has not fallen. She has not left the home in weeks except for short walks. She has a history of hypertension, hyperlipidemia, atrial fibrillation, and hypothyroidism. She takes levothyroxine, aspirin, warfarin, donepezil, verapamil, lisinopril, atorvastatin, and a multivitamin daily. Her temperature is 37°C (98.4°F), pulse is 66/min, respirations are 13/min, and blood pressure is 126/82 mm Hg. Physical examination shows no abnormalities. It is important to the family that the patient continues her care in the home. Which of the following recommendations is most appropriate at this time?", "answer": "Adhere to a regular sleep schedule", "options": {"A": "Start quetiapine daily", "B": "Start lorazepam as needed", "C": "Adhere to a regular sleep schedule", "D": "Frequently play classical music", "E": "Schedule frequent travel\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old man is hospitalized for an elective gastrointestinal surgery 24 hours before the scheduled day of surgery. The surgeon has ordered food and fluids to be withheld from the patient from 12 hours before the surgery and the administration of intravenous isotonic saline. Based on his body weight, his fluid requirement for 12 hours is 900 mL. However, the following day, the surgeon finds that 3 pints of isotonic fluid (1 pint = 500 mL) were administered over the preceding last 12 hours. Which of the following options best describes the resulting changes in the volume of intracellular fluid (ICF) and the body osmolality of the patient?", "answer": "No change in ICF volume, no change in body osmolality", "options": {"A": "Increased ICF volume, no change in body osmolality", "B": "Increased ICF volume, decreased body osmolality", "C": "Decreased ICF volume, no change in body osmolality", "D": "Decreased ICF volume, increased body osmolality", "E": "No change in ICF volume, no change in body osmolality"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 50-year-old man presents to the emergency department with a complaint of crushing chest pain. The pain started suddenly 30 minutes ago while he was walking his dog. The patient also complains of difficulty breathing and palpitations. The pain is described as starting behind the sternum and moving towards the left jaw. Medical history includes recently diagnosed hypercholesterolemia and peptic ulcer disease. He currently takes atorvastatin and omeprazole. The patient has smoked a pack of cigarettes per day for 10 years and consumes 2–3 beers on the weekends. His blood pressure is 148/90 mm Hg, the pulse is 106/min, and the respiratory rate is 22/min. Examination shows him to be visibly distressed, diaphoretic, and slightly hunched over. Aspirin is administered and blood work is sent to the laboratory. His ECG is shown in the picture. What is the best next step for this patient?", "answer": "Urgent percutaneous coronary intervention", "options": {"A": "Start heparin infusion and ICU admission", "B": "Perform an urgent bedside echocardiography", "C": "Urgent percutaneous coronary intervention", "D": "Monitor closely and wait for cardiac troponin levels", "E": "Order an urgent chest CT scan and provide analgesia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old man is brought to the emergency department by his wife for evaluation of abnormal behavior that began 2 weeks ago. The patient has not slept in over a week and has been partying each night. He has never done this before. The patient has also been skipping work and purchased a car last week with money they had saved for their vacation to Italy. He has a past medical history of major depressive disorder and systemic lupus erythematosus. He normally drinks 2 beers per week but has been drinking 6–10 beers per day for the past two weeks. Current medications include hydroxychloroquine. He appears agitated and is wearing bright-colored mismatched clothing. His temperature is 36°C (96.8°F), pulse is 94/min, respirations are 18/min, and blood pressure is 130/85 mm Hg. Physical examination shows no abnormalities. On mental status examination, his speech is pressured and his thought process is tangential. A complete blood count, serum electrolytes, and liver enzyme activities are within the reference range; his serum creatinine is 1.8 mg/dL. Urinalysis shows 2+ proteinuria, and WBC casts. Toxicology screening is negative. This patient would most likely benefit from which of the following long-term treatments?", "answer": "Valproate", "options": {"A": "Dialectical behavioral therapy", "B": "Valproate", "C": "Clonazepam", "D": "Lithium", "E": "Escitalopram\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old caucasian female comes to the physician because of chronic diarrhea and abdominal bloating that started 6 months ago. She also reports increasing fatigue and intermittent tingling in her hands and feet. She lost 5 kg (11 lb) of weight over the past 6 months without changing her diet or trying to lose weight. She and her husband have been trying to conceive for over a year without any success. Menses have been irregular at 28–45 day intervals and last for 1–2 days. She has generalized anxiety disorder for which she takes sertraline. Her height is 151 cm and weight is 50 kg; BMI is 22 kg/m2. Examination shows generalized pallor. Cardiopulmonary examination is normal. Test of the stool for occult blood is negative. Laboratory studies show:\nHemoglobin 9.5 g/dL\nLeukocyte count 3900/mm3\nPlatelet count 130,000/mm3\nSerum\nGlucose 100 mg/dL\nCreatinine 0.6 mg/dL\nThyroid-stimulating hormone 3.3 μU/mL\nVitamin B12 80 pg/mL (N > 200)\nIgA anti-tissue transglutaminase antibody negative\nSerum IgA decreased\nWhich of the following is the most appropriate next step in diagnosis?\"", "answer": "IgG deamidated gliadin peptide test", "options": {"A": "Plasma zinc concentration", "B": "Fecal fat test", "C": "IgG deamidated gliadin peptide test", "D": "IgA endomysial antibody", "E": "Skin prick test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-year-old boy presents with difficulty swallowing, diarrhea, itching, and weakness. He also complains of episodes of headaches, sweating, and palpitations, which are accompanied by fear and tend to end with micturition. His mother is concerned about the strange nodules on his lips and eyelids. The boy's younger brother had similar nodules and died at 10 years of age of unknown causes. The patient’s vital signs are as follows: blood pressure 130/80 mm Hg, heart rate 107/min, respiratory rate 14/min, and temperature 36.9℃ (98.4℉). The child is tall, thin, has disproportionately long arms and legs, and increased thoracic spine kyphosis. There are multiple yellow-white, sessile, painless nodules on the patient’s lips, and buccal and eyelid mucosa. There is a painless lump in the area of the left thyroid lobe and enlargement of the posterior cervical lymph nodes on the left side. What is the most probable embryonic origin of the cells in the lump?", "answer": "Neural crest cells", "options": {"A": "First pharyngeal groove", "B": "First pharyngeal pouch", "C": "Lateral plate mesoderm", "D": "Neurogenic placodes", "E": "Neural crest cells"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old woman with well-controlled HIV on antiretroviral therapy comes to the physician because of a 2-week history of a painless lesion on her right calf. Many years ago, she had a maculopapular rash over her trunk, palms, and soles that resolved spontaneously. Physical examination shows a 4-cm firm, non-tender, indurated ulcer with a moist, dark base and rolled edges. There is a similar lesion at the anus. Results of rapid plasma reagin testing are positive. Which of the following findings is most likely on microscopic examination of these lesions?", "answer": "Coagulative necrosis surrounded by fibroblast and macrophage infiltrate", "options": {"A": "Epithelioid cell infiltrate surrounding acellular, granular core", "B": "Epidermal hyperplasia with dermal lymphocytic infiltrate", "C": "Lichenoid hyperplasia with superficial neutrophilic infiltrate", "D": "Ulcerated epidermis with plasma cell infiltrate", "E": "Coagulative necrosis surrounded by fibroblast and macrophage infiltrate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 58-year-old man presents to his primary care physician with a 3-week history of increasing pain in his legs and feet. Specifically, he says that he has been getting electric shock sensations that started in his feet, but have progressed up his leg. In addition, the pain is accompanied by numbness and tingling in his hands and feet bilaterally. His past medical history is significant for poorly controlled type 2 diabetes mellitus. Given these symptoms, his physician prescribes a new drug to help him cope with these symptoms. Which of the following is the mechanism of action for the medication that was most likely prescribed in this case?", "answer": "Serotonin norepinephrine reuptake inhibitor", "options": {"A": "Binding to mu opioid receptors", "B": "Increased duration of GABA channel opening", "C": "Increased frequency of GABA channel opening", "D": "Selective serotonin reuptake inhibitor", "E": "Serotonin norepinephrine reuptake inhibitor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 22-year-old soldier sustains a stab wound to his chest during a military attack in Mali. He is brought to the combat medic by his unit for a primary survey. The soldier reports shortness of breath. He is alert and oriented to time, place, and person. His pulse is 99/min, respirations are 32/min, and blood pressure is 112/72 mm Hg. Examination shows a 2-cm wound at the left fourth intercostal space at the midclavicular line. Bubbling of blood is seen with each respiration at the wound site. There is no jugular venous distention. There is hyperresonance to percussion and decreased breath sounds on the left side. The trachea is at the midline. Which of the following is the most appropriate next step in management?", "answer": "Partially occlusive dressing", "options": {"A": "Partially occlusive dressing", "B": "Emergency pericardiocentesis", "C": "Emergency echocardiography", "D": "Needle thoracostomy", "E": "Supplemental oxygen\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old G1P1 woman comes to the clinic asking about “the morning after pill.” She reports that she had sexual intercourse with her boyfriend last night and she thinks the condom broke. She is not using any other form of contraception. She reports her last menstrual period was 10 days ago, and they are normally regular. The patient’s medical history is significant for obesity, asthma and allergic rhinitis. Her medications include albuterol and occasional intranasal corticosteroids. She has no history of sexually transmitted diseases and is sexually active with only her current boyfriend of 5 years. The patient denies genitourinary symptoms. Her temperature is 98°F (36.7°C), blood pressure is 112/74 mmHg, pulse is 63/min, and respirations are 12/min with an oxygen saturation of 99% O2 on room air. Physical examination, including a pelvic exam, shows no abnormalities. The patient is worried because she is back in graduate school and cannot afford another child. Which of the following is the most effective emergency contraception?", "answer": "Copper intrauterine device", "options": {"A": "Copper intrauterine device", "B": "High-dose oral contraceptive therapy", "C": "Levonorgesterel pill", "D": "Levonorgesterel-releasing intrauterine device", "E": "Ulipristal pill"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-year-old adolescent boy presents to his pediatrician for his scheduled follow-up after he was prescribed low-dose methylphenidate for treatment of attention-deficit/hyperactivity disorder 4 weeks ago. On follow-up, his mother reports mild improvement in his symptoms, but she also notes that his appetite has decreased significantly after starting the medication. This has led to a 1.6 kg (3.5 lb) weight loss over the last 4 weeks. His mother also reports that she no longer wants to continue the drug. Which of the following is the next drug of choice for pharmacological management of the condition?", "answer": "Atomoxetine", "options": {"A": "Atomoxetine", "B": "Clonidine", "C": "Dexmethylphenidate", "D": "Dextroamphetamine", "E": "Imipramine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator is studying the metabolism of an experimental drug that is known to have first order kinetics. Immediately after administering an intravenous dose of the drug to a patient, the serum concentration is 60 U/L. 3 hours later, the serum concentration of the drug is 30 U/L. 9 hours after administration, the serum concentration of the drug is most likely to be which of the following?", "answer": "7.5 U/L", "options": {"A": "5 U/L", "B": "3.75 U/L", "C": "7.5 U/L", "D": "15 U/L", "E": "0 U/L"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 26-year-old gravida-1-para-0 (G-1-P-0) presents for a routine prenatal check-up at 16 weeks gestation. The patient has no concerns but is excited to learn the gender of the baby. Genetic testing was performed that showed an XY genotype; however, an ultrasound does not reveal the development of external male genitalia. Which of the following is responsible for the initial step of the development of male characteristics?", "answer": "SRY gene product", "options": {"A": "Formation of the genital ridge", "B": "Formation of the paramesonephric duct", "C": "Conversion of testosterone to DHT", "D": "SRY gene product", "E": "Production of anti-Mullerian hormone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 82-year-old woman presents to the emergency department after a fall. Imaging reveals diffuse trauma to the left humerus from the midshaft to the olecranon process with shearing of the periosteum. The orthopedic surgeon suggests a follow-up in 2 weeks. In that time, the patient develops worsening pain. At follow-up, she is found to have diffuse bone necrosis from the midshaft of the left humerus to the olecranon process. with no involvement of the distal arm structures. Which of the following structures must have been damaged to cause this diffuse bone necrosis?", "answer": "Volkmann’s canal", "options": {"A": "Haversian canal", "B": "Brachial artery", "C": "Volkmann’s canal", "D": "Ulnar nerve", "E": "Epiphyseal plate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 7-year-old boy with a sore throat, fever, and generalized malaise is admitted to the pediatric floor. On physical examination, he has diffuse white exudate on both tonsils, and also a palpable spleen with mild hepatomegaly. His blood smear shows large and abundant lymphocytes with blue-gray cytoplasm, irregular nuclei, and dark chromatin with inconspicuous nucleoli. Which of the following is the most likely diagnosis?", "answer": "Infectious mononucleosis", "options": {"A": "Infectious mononucleosis", "B": "Cytomegalovirus infection", "C": "Toxoplasmosis", "D": "Graves' disease", "E": "Viral hepatitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 71-year-old man is brought to the emergency department because of severe, progressive left leg pain and tingling for 8 hours. The symptoms began while he was watching television. For several months, the patient has noticed calf cramping when going for long walks, as well as occasional foot tingling and numbness, but did not seek medical attention. He has no history of recent injuries. He has poorly-controlled hypertension, hyperlipidemia, type 2 diabetes mellitus, and osteoarthritis. He smoked one pack of cigarettes daily for 35 years but quit 15 years ago. He drinks three beers every night. Current medications include lisinopril, metoprolol succinate, atorvastatin, metformin, and ibuprofen. He appears to be in severe pain and is clutching his left leg. His temperature is 37.4°C (99.3°F), pulse is 110/min, respirations are 18/min, and blood pressure is 163/94 mm Hg. The lungs are clear to auscultation. There is a harsh II/VI systolic ejection murmur best heard at the right upper sternal border. The abdomen is soft and nontender. The left leg is cool to the touch with decreased popliteal, posterior tibial, and dorsalis pedis pulses. There is 5/5 strength on left hip, knee, and ankle testing. The left hip, knee, and ankle show no gross effusion, erythema, or tenderness to palpation. The remainder of the examination shows no abnormalities. Which of the following is most likely to confirm the diagnosis?", "answer": "Digital subtraction angiography", "options": {"A": "Creatine kinase concentration", "B": "Digital subtraction angiography", "C": "Fibrin degradation products", "D": "Ankle-brachial index", "E": "Compartment pressures\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old gravida 2 para 1 is receiving care from her obstetrician at 28 weeks. She states that she has been having suprapubic pain and urinary frequency for the past week. Her past medical history is significant for dermatomyositis for which she takes prednisone every day. She does not smoke cigarettes or drinks alcohol. Her vital signs are within normal limits. Physical examination of the patient is within normal limits. A urine sample from the patient shows > 100,000 CFU of Escherichia coli. Urinalysis results are provided as follows:\nLeukocyte esterase  positive\nWBC 50-100 cells/HPF\nNitrite positive\nRBC 2 cells/HPF\nEpithelial cells 2 cells/HPF\nUrine pH 5.2\nWhich of the following is the best pharmacotherapy for this patient’s condition?", "answer": "Nitrofurantoin", "options": {"A": "Trimethoprim-sulfamethoxazole", "B": "Nitrofurantoin", "C": "Tetracycline", "D": "Cephalexin", "E": "Amoxicillin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old woman visits her primary care physician complaining of abdominal pain for the past 6 months. She reports that the pain is localized to her lower abdomen and often resolves with bowel movements. She states that some days she has diarrhea while other times she will go 4-5 days without having a bowel movement. She started a gluten-free diet in hopes that it would help her symptoms, but she has not noticed much improvement. She denies nausea, vomiting, hematochezia, or melena. Her medical history is significant for generalized anxiety disorder and hypothyroidism. Her father has a history of colon cancer. The patient takes citalopram and levothyroxine. Physical examination reveals mild abdominal tenderness with palpation of lower quadrant but no guarding or rebound. A guaiac test is negative. A complete blood count is pending. Which of the following is the next best step in management?", "answer": "Colonoscopy", "options": {"A": "Anti-endomysial antibody titer", "B": "Colonoscopy", "C": "High fiber diet", "D": "Loperamide", "E": "Thyroid ultrasound"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old woman comes to the physician because of severe pain in her right wrist one day after falling onto her hands and knees while rollerskating. Physical examination shows abrasions over the knees and bruising over the volar aspect of the right wrist. There is swelling and tenderness on palpation of the volar wrist joint, as well as restricted range of motion due to pain. An x-ray of the hand shows volar dislocation of the lunate bone. Further evaluation is most likely to show which of the following?", "answer": "Paresthesia over the volar aspect of the first 3 fingers on wrist flexion", "options": {"A": "Paresthesia over the volar aspect of the first 3 fingers on wrist flexion", "B": "Anesthesia over the dorsal aspect of the first 3 fingers", "C": "Tenderness to palpation of the anatomic snuffbox", "D": "Involuntary flexion of the 4th and 5th interphalangeal joints when extending all fingers", "E": "Pale skin color on the volar surface when pressure is applied to the radial artery"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old man with hypertension comes to the physician for a follow-up examination. His blood pressure is 165/92 mm Hg on the left arm and 162/90 mm Hg on the right arm. He reports that he is compliant with his medication and exercise regimen. The physician adds a drug to his antihypertensive medication regimen. This drug increases serum renin, angiotensin I, and angiotensin II levels, and decreases serum aldosterone levels, without affecting bradykinin levels. Which of the following drugs was most likely added to this patient's medication regimen?", "answer": "Candesartan", "options": {"A": "Candesartan", "B": "Aliskiren", "C": "Lisinopril", "D": "Triamterene", "E": "Metoprolol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man comes to the physician because of a 6-month history of muscle weakness. During this period, the patient has had low energy, intermittent nosebleeds, and a 5-kg (11-lb) weight loss. He also reports progressive hearing and vision problems. He has a history of pins-and-needles sensation, numbness, and pain in his feet. Vital signs are within normal limits. Physical examination shows a palpable liver tip 2–3 cm below the right costal margin. There is nontender lympadenopathy in the groins, axillae, and neck. Laboratory studies show:\nHemoglobin 8.8 g/dL\nWhite blood cells 6,300/mm3\nPlatelet count 98,000/mm3\nErythrocyte sedimentation rate 70 mm/h\nSerum\nNa+ 136 mmol/L\nK+ 3.6 mmol/L\nCr 1.3 mg/dL\nCa2+ 8.6 mg/dL\nAspartate aminotransferase 32 U/L\nAlanine aminotransferase 36 U/L\nAlkaline phosphatase 100 U/L\nLactate dehydrogenase 120 U/L\nA serum protein electrophoresis exhibits a sharp, narrow spike of monoclonal IgM immunoglobulin. Which of the following is the most likely diagnosis?\"", "answer": "Waldenstrom macroglobulinemia", "options": {"A": "Hairy cell leukemia", "B": "Multiple myeloma", "C": "Waldenstrom macroglobulinemia", "D": "Monoclonal gammopathy of undetermined significance", "E": "Mantle cell lymphoma\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A previously healthy 6-week-old infant is brought to the emergency department because of fever, fatigue, and dry cough for one day. She has been feeding poorly and had difficulty latching on to breastfeed since yesterday. She has had nasal congestion. The mother reports that her daughter has not been going through as many diapers as usual. She was born by uncomplicated vaginal delivery at 42 weeks' gestation. Her mother is a cystic fibrosis carrier. The patient has been treated with acetaminophen for the last 24 hours, and vitamin D drops since birth. She appears irritable, pale, and lethargic. She is at the 25th percentile for both length and weight; she had the same percentiles at birth. Her temperature is 38.2°C (100.7°F) and respirations are 64/min. Pulse oximetry on room air shows an oxygen saturation of 92%. Examination shows an ill-appearing infant with a cough and nasal flaring. Mucous membranes are dry. Chest examination shows intercostal and supraclavicular retractions. Expiratory wheezes are heard on auscultation. Which of the following is the most likely causal organism?", "answer": "Respiratory syncytial virus", "options": {"A": "Listeria monocytogenes", "B": "Respiratory syncytial virus", "C": "Rhinovirus", "D": "Coronavirus", "E": "Streptococcus pneumoniae"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 38-year-old woman presents to the physician’s clinic with a 6-month history of generalized weakness that usually worsens as the day progresses. She also complains of the drooping of her eyelids and double vision that is worse in the evening. Physical examination reveals bilateral ptosis after a sustained upward gaze and loss of eye convergence which improves upon placing ice packs over the eyes and after the administration of edrophonium. Which of the following is an intrinsic property of the muscle group affected in this patient?", "answer": "High ATPase activity", "options": {"A": "High myoglobin content", "B": "Increased amount of ATP generated per molecule of glucose", "C": "A small mass per motor unit", "D": "High ATPase activity", "E": "High density of mitochondria"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old professional wrestler recently participated in a charitable tournament event in Bora Bora, a tropical island that is part of the French Polynesia Leeward Islands. During his stay, he wore tight-fitting clothes and tight bathing trunks for extended periods. After 6 days, he observed symmetric, erythematous itchy rash in his groin, with a significant amount of moisture and scales. Central areas of the rash were hyperpigmented, and the border was slightly elevated and sharply demarcated. His penis and scrotum were not affected. He immediately visited a local dermatology clinic where a specialist conducted a Wood lamp examination to exclude the presence of a bacterial infection (primary infection due to Corynebacterium minutissimum). The working diagnosis was a fungal infection. Which topical agent should be recommended to treat this patient?", "answer": "Terbinafine", "options": {"A": "Nystatin", "B": "Ketoconazole", "C": "Terbinafine", "D": "Betamethasone/clotrimazole combination", "E": "Miconazole"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 59-year-old woman comes to the clinic complaining of an intermittent, gnawing epigastric pain for the past 2 months. The pain is exacerbated with food and has been getting progressively worse. The patient denies any weight changes, nausea, vomiting, cough, or dyspepsia. Medical history is significant for chronic back pain for which she takes ibuprofen. Her father passed at the age of 55 due to pancreatic cancer. Labs were unremarkable except for a mild decrease in hemoglobin. To what medication is most appropriate to be switched from the current medication at this time?", "answer": "Acetaminophen", "options": {"A": "Acetaminophen", "B": "Aspirin", "C": "Naproxen", "D": "Omeprazole", "E": "Ranitidine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 57-year-old woman presents to the emergency department for laboratory abnormalities detected by her primary care physician. The patient went to her appointment complaining of difficulty using her hands and swelling of her arms and lower extremities. The patient has notably smooth skin that seems to have not aged considerably. Upon seeing her lab values, her physician sent her to the ED. The patient has a past medical history of multiple suicide attempts, bipolar disorder, obesity, diabetes, and anxiety. Her current medications include lithium, insulin, captopril, and clonazepam. The patient's laboratory values are below.\n\nSerum:\nNa+: 140 mEq/L\nK+: 5.2 mEq/L\nCl-: 100 mEq/L\nHCO3-: 20 mEq/L\nBUN: 39 mg/dL\nGlucose: 127 mg/dL\nCreatinine: 2.2 mg/dL\nCa2+: 8.4 mg/dL\n\nThe patient is restarted on her home medications. Her temperature is 99.5°F (37.5°C), pulse is 80/min, blood pressure is 155/90 mmHg, respirations are 11/min, and oxygen saturation is 97% on room air. Which of the following is the best next step in management?", "answer": "Start valproic acid and discontinue lithium", "options": {"A": "Continue medications and start metformin", "B": "Continue medications and start furosemide", "C": "Continue medications and add nifedipine", "D": "Start lisinopril and discontinue captopril", "E": "Start valproic acid and discontinue lithium"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 7-year-old patient is brought in by his mother for a routine check-up for school. The child is cooperative throughout the visit and excitedly talks about school. The mother congratulates her son on his behavior, and mentions that when he was being treated for leukemia three years ago, he would start crying in the parking lot even before they arrived at the clinic for his blood checks. The mother notes that since his remission, he has been better tolerating physician visits. She has occasionally been giving him candy before clinic visits to reward his good behavior after she noticed he stopped crying. Since getting these rewards, the patient has sometimes remarked that he enjoys visiting the clinic now. Which of the following best explains why this patient no longer cries at physician visits?", "answer": "Extinction", "options": {"A": "Classical conditioning", "B": "Positive reinforcement", "C": "Extinction", "D": "Acting out", "E": "Reaction formation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 3-week-old infant is brought to the emergency department 6 hours after the onset of fever and persistent irritability. He had been well until 2 days ago, when he started feeding poorly and sleeping more than usual. He appears lethargic and irritable when roused for examination. His temperature is 39°C (102°F). He cries when he is picked up and when his neck is flexed. The remainder of the physical and neurological examinations show no other abnormalities. His serum glucose is 115 mg/mL. His total serum bilirubin is 6.3 mg/dL. Cerebrospinal fluid analysis shows:\nPressure 255 mm H2O\nErythrocytes 2/mm3\nLeukocyte count 710/mm3\nSegmented neutrophils 95%\nLymphocytes 5%\nProtein 86 mg/dL\nGlucose 22 mg/dL\nGram stain results of the cerebrospinal fluid are pending. Which of the following is the most appropriate initial antibiotic regimen for this patient?\"", "answer": "Ampicillin, gentamicin, and cefotaxime", "options": {"A": "Ampicillin and ceftriaxone", "B": "Gentamicin and cefotaxime", "C": "Ampicillin, gentamicin, and cefotaxime", "D": "Vancomycin, ampicillin, and cefotaxime", "E": "Vancomycin, ampicillin, and doxycycline"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old primigravida presents at 16 weeks gestation for a check-up. She has no co-existing diseases. Currently, she has no subjective complaints, but she worries about the results of her triple screen. She takes 400 mg of folic acid and 30 mg of iron daily. The results of the triple screen are shown below.\n  Measured values Reference values\nMaternal serum alpha-fetoprotein 2.9 MoM 0.85-2.5 MoM\nBeta-hCG 1.1 MoM 0.5-1 MoM\nUnconjugated estriol 1 MoM 0.5-3 MoM\nWhat would be the most proper next step in the management of this patient?", "answer": "Perform ultrasound examination", "options": {"A": "Perform amniocentesis", "B": "Recommend additional inhibit A test", "C": "Perform ultrasound examination", "D": "Test for CMV infection, rubella, and toxoplasmosis", "E": "Arrange a chorionic villus sampling procedure"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 71-year-old woman comes to the physician because of a 4-month history of worsening cough and a 4.5-kg (10-lb) weight loss. She has smoked one pack of cigarettes daily for 35 years. Physical examination shows wheezing over the right lung fields. Laboratory studies show a serum calcium concentration of 12.5 mg/dL. X-rays of the chest are shown. Which of the following is the most likely diagnosis?", "answer": "Squamous cell lung carcinoma", "options": {"A": "Lobar pneumonia", "B": "Small cell lung carcinoma", "C": "Tuberculosis", "D": "Sarcoidosis", "E": "Squamous cell lung carcinoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-year-old boy presents with recurrent joint pain that migrates from joint to joint and intermittent fever for the last several weeks. He also says that he has no appetite and has been losing weight. The patient is afebrile, and vital signs are within normal limits. On physical examination, he is pale with diffuse petechial bleeding and bruises on his legs. An abdominal examination is significant for hepatosplenomegaly. Ultrasound of the abdomen confirms hepatosplenomegaly and also shows multiple enlarged mesenteric lymph nodes. A complete blood count (CBC) shows severe anemia and thrombocytopenia with leukocytosis. Which of the following is the most likely diagnosis in this patient?", "answer": "Acute leukemia", "options": {"A": "Acute leukemia", "B": "Tuberculosis of the bone marrow", "C": "Aplastic anemia", "D": "Immunologic thrombocytopenic purpura", "E": "Chronic leukemia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56 year old female comes to the ED complaining of moderate right eye pain, headache, and acute onset of blurry vision, which she describes as colored halos around lights. She was watching a movie at home with her husband about an hour ago when the pain began. On physical exam of her right eye, her pupil is mid-dilated and unresponsive to light. Her right eyeball is firm to pressure. Intraocular pressure (IOP) measured with tonometer is elevated at 36mmHg. Which of the following is the most appropriate emergency treatment?", "answer": "Timolol ophthalmic solution", "options": {"A": "Timolol ophthalmic solution", "B": "Epinephrine ophthalmic solution", "C": "Laser peripheral iridotomy", "D": "Anti-cholinergic ophthalmic solution", "E": "NSAID ophthalmic solution"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought to the emergency department because of worsening confusion for the last hour. He has had high-grade fever, productive cough, fatigue, and malaise for the past 2 days. He has not seen a physician in several years. His temperature is 38.9°C (102°F), pulse is 133/min, respirations are 33/min, and blood pressure is 86/48 mm Hg. He is lethargic and minimally responsive. Mucous membranes are dry. Pulmonary examination shows subcostal retractions and coarse crackles bilaterally. Laboratory studies show a hemoglobin concentration of 8.4 g/dL and a leukocyte count of 16,000/mm3. A peripheral blood smear shows sickled red blood cells. Which of the following pathogens is the most likely cause of this patient's current condition?", "answer": "Streptococcus pneumoniae", "options": {"A": "Salmonella paratyphi", "B": "Streptococcus pneumoniae", "C": "Neisseria meningitidis", "D": "Staphylococcus aureus", "E": "Nontypeable Haemophilus influenzae"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old female with abdominal pain undergoes laparoscopic surgery. An outpouching of tissue is excised from the ileum and sent to the laboratory for evaluation. The pathologist notes inflammation and the presence of mucosa, submucosa, and muscle in the walls of the specimen. Which of the following is the most likely diagnosis?", "answer": "Meckel's diverticulum", "options": {"A": "Hirschprung's disease", "B": "Crohn's disease", "C": "Meckel's diverticulum", "D": "Appendicitis", "E": "Henoch-Schonlein purpura"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 33-year-old woman schedules an appointment at an outpatient clinic for the first time after moving to the US from Peru a few months ago. She complains of easy fatigability and shortness of breath with minimal exertion for the past 6 months. She further adds that her breathlessness is worse when she goes to bed at night. She is also concerned about swelling in her legs. As a child, she says she always had sore throats. She does not smoke or drink alcohol. Medical records are unavailable, but the patient says that she has always been healthy apart from her sore throats. The blood pressure is 114/90 mm Hg, the pulse is 109/min, the respiratory rate is 26/min, and the temperature is 36.7°C (98°F). On examination, she is icteric with distended jugular veins. Bilateral basal crepitations are audible on auscultation of the lungs. Also, a high-pitched apical holosystolic murmur is audible that radiates to the left axilla. A transthoracic echocardiogram reveals mitral regurgitation with an ejection fraction of 25%. Treatment should focus on which of the following?", "answer": "Decrease total peripheral resistance", "options": {"A": "Decrease total peripheral resistance", "B": "Increase inotropy of cardiac muscle", "C": "Increase left ventricular end diastolic pressure", "D": "Increase the rate of SA node discharge", "E": "Increase coronary blood flow"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old man with chronic kidney failure is brought to to the emergency department by ambulance after he passed out during dinner. On presentation, he is alert and complains of shortness of breath as well as chest palpitations. An EKG is obtained demonstrating an irregular rhythm consisting of QT amplitudes that vary in height over time. Other findings include uncontrolled contractions of his muscles. Tapping of his cheek does not elicit any response. Over-repletion of the serum abnormality in this case may lead to which of the following?", "answer": "Bradycardia", "options": {"A": "Bradycardia", "B": "Diffuse calcifications", "C": "Kidney stones", "D": "Peaked T-waves", "E": "Seizures"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old man with recurrent pneumonia comes to the physician for a follow-up examination one week after hospitalization for pneumonia. He feels well but still has a productive cough. He has smoked 1 pack of cigarettes daily for 5 years. His temperature is 36.9°C (98.4°F) and respirations are 20/min. Cardiopulmonary examination shows coarse crackles at the right lung base. Microscopic examination of a biopsy specimen of the right lower lung parenchyma shows proliferation of clustered, cuboidal, foamy-appearing cells. These cells are responsible for which of the following functions?", "answer": "Lecithin production", "options": {"A": "Lecithin production", "B": "Cytokine release", "C": "Toxin degradation", "D": "Gas diffusion", "E": "Mucus secretion"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A pediatrician is called to examine a recently born dysmorphic boy. The birth weight was 1.6 kg (3.5 lb). On physical examination of the face and skull, the head was shown to be microcephalic with a prominent occiput and a narrow bifrontal diameter. The jaw was comparatively small with short palpebral fissures. The nose was narrow and the nasal ala was hypoplastic. Examination of the upper limbs revealed closed fists with the index fingers overlapping the 3rd fingers, and the 5th fingers overlapping the 4th fingers. The fingernails and toenails were hypoplastic and he had rocker-bottom feet. Based on these details, you suspect a particular chromosomal anomaly. Which of the following statements best describes this patient’s condition?", "answer": "95% of these patients die in the 1st year of life.", "options": {"A": "This condition is associated with teenage mothers.", "B": "95% of these patients die in the 1st year of life.", "C": "The condition is more common in males.", "D": "Thrombocytopenia is the least common hematologic abnormality in these patients.", "E": "The most common congenital heart disease is patent ductus arteriosus."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old man comes to the emergency department because of nausea, headache, and generalized fatigue for 2 days. He has not vomited. He was diagnosed with small cell lung cancer and liver metastases around 3 months ago and is currently receiving chemotherapy with cisplatin and etoposide. His last chemotherapy cycle ended one week ago. He has chronic obstructive lung disease and type 2 diabetes mellitus. Current medications include insulin and a salmeterol-fluticasone inhaler. He appears malnourished. He is oriented to time, place, and person. His temperature is 37.1°C (98.8°F), pulse is 87/min, respirations are 13/min, and blood pressure is 132/82 mm Hg. There is no edema. Examination shows decreased breath sounds over the left lung. Cardiac examination shows an S4. The abdomen is soft and nontender. Neurological examination shows no focal findings. Laboratory studies show:\nHemoglobin 11.6 g/dL\nLeukocyte count 4,300/mm3\nPlatelet count 146,000/mm3\nSerum\nNa+ 125 mEq/L\nCl− 105 mEq/L\nK+ 4.5 mEq/L\nHCO3− 24 mEq/L\nGlucose 225 mg/dL\nTotal bilirubin 1.1 mg/dL\nAlkaline phosphatase 80 U/L\nAspartate aminotransferase (AST, GOT) 78 U/L\nAlanine aminotransferase (ALT, GPT) 90 U/L\nFurther evaluation of this patient is likely to show which of the following laboratory findings?\nSerum osmolality Urine osmolality Urinary sodium excretion\n(A) 220 mOsm/kg H2O 130 mOsm/kg H2O 10 mEq/L\n(B) 269 mOsm/kg H2O 269 mOsm/kg H2O 82 mEq/L\n(C) 255 mOsm/kg H2O 45 mOsm/kg H2O 12 mEq/L\n(D) 222 mOsm/kg H2O 490 mOsm/kg H2O 10 mEq/L\n(E) 310 mOsm/kg H2O 420 mOsm/kg H2O 16 mEq/L\"", "answer": "(B)", "options": {"A": "(A)", "B": "(B)", "C": "(C)", "D": "(D)", "E": "(E)\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old woman repetitively visits the general surgery clinic worried that her inguinal hernia is incarcerated. 2 months ago, she was seen in the emergency department where she presented with a left lower abdominal swelling. The mass was easily reduced and the patient was referred to the general surgery clinic for elective surgical repair. Because her condition was deemed not urgent, she was informed that she was down on the surgical waiting list. Despite this, she continues to visit the clinic and the ED worried that her bowels are ‘trapped and dying.’ Each time she is reassured and any protrusion present is quickly reduced. She has previously frequently visited her primary care physician for complaints of abdominal pain and inconsistent bowel habits, but no etiology could be identified. She continues to intermittently have these symptoms and spends hours every day worrying about what may be going on. She has no other significant past medical history. Which of the following is the most appropriate diagnosis?", "answer": "Somatic symptom disorder", "options": {"A": "Conversion disorder", "B": "Malingering disorder", "C": "Factitious disorder", "D": "Illness anxiety disorder", "E": "Somatic symptom disorder"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to the physician by his parents for a well-child examination. The boy was born at term via vaginal delivery and has been healthy except for impaired vision due to severe short-sightedness. He is at the 97th percentile for height and 25th percentile for weight. Oral examination shows a high-arched palate. He has abnormally long, slender fingers and toes, and his finger joints are hyperflexible. The patient is asked to place his thumbs in the palms of the same hand and then clench to form a fist. The thumbs are noted to protrude beyond the ulnar border of the hand. Slit lamp examination shows lens subluxation in the superotemporal direction bilaterally. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Mutation in fibrillin-1 gene", "options": {"A": "Mutation in fibrillin-1 gene", "B": "Defective collagen cross-linking", "C": "Nondisjunction of sex chromosomes", "D": "Mutation of the FMR1 gene", "E": "Mutation in RET gene"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A patient presents to the emergency department with abdominal pain. While having dinner, the patient experienced pain that prompted the patient to come to the emergency department. The patient states that the pain is episodic and radiates to the shoulder. The patient's temperature is 98°F (36.7°C), blood pressure is 120/80 mmHg, pulse is 80/min, respirations are 13/min, and oxygen saturation is 98% on room air. Laboratory values are ordered and return as below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 4,500 cells/mm^3 with normal differential\nPlatelet count: 247,000/mm^3\n\nSerum:\nNa+: 140 mEq/L\nCl-: 100 mEq/L\nK+: 4.6 mEq/L\nHCO3-: 24 mEq/L\nBUN: 15 mg/dL\nGlucose: 90 mg/dL\nCreatinine: 0.8 mg/dL\nCa2+: 10.0 mg/dL\nAST: 11 U/L\nALT: 11 U/L\n\nOn physical exam, the patient demonstrates abdominal tenderness that is most prominent in the right upper quadrant. Which of the following represents the most likely demographics of this patient?", "answer": "A middle-aged overweight mother", "options": {"A": "A middle-aged male with a positive urea breath test", "B": "A middle-aged overweight mother", "C": "A middle-aged patient with a history of bowel surgery", "D": "An elderly diabetic with vascular claudication", "E": "An elderly smoker with painless jaundice"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old man comes to the physician for evaluation of multiple red spots on his trunk. He first noticed these several months ago, and some appear to have increased in size. One day ago, he scratched one of these spots, and it bled for several minutes. Physical examination shows the findings in the photograph. Which of the following is the most likely diagnosis?", "answer": "Cherry angioma", "options": {"A": "Cherry angioma", "B": "Amelanotic melanoma", "C": "Spider angioma", "D": "Seborrheic keratosis", "E": "Pyogenic granuloma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old man is brought by his wife to the emergency department due to sudden onset confusion that started 40 minutes ago. The patient’s wife says that he came home from work complaining of pain in his arms and legs. While resting on the couch, he mentioned feeling nauseous and then became quite confused. He has no previous medical history and takes no medications. He does not smoke and only drinks alcohol occasionally. His vital signs include pulse 80/min, respiratory rate 12/min, blood pressure 120/84 mm Hg, and SaO2 99% on room air. On physical examination, the patient is oriented x 0 and unable to answer questions or follow commands. Generalized pallor is present. There are also multiple scratches on the face and neck due to constant itching. Assuming this patient’s symptoms are due to his employment, he most likely works as which of the following?", "answer": "Diving instructor", "options": {"A": "Bird keeper", "B": "Diving instructor", "C": "Farmer", "D": "Fireman", "E": "Shipyard worker"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy goes camping with his parents in the Appalachian mountains of Western North Carolina. While on the hiking trip, he is exposed to an antigen. After the exposure, this antigen is phagocytosed by a CD4+ T helper cell and is presented on an MHC class II molecule. This CD4+ T helper cell encounters a B cell in the lymph node shown in the image below. The mature B cell proliferates and differentiates to produce antibodies to target this antigen. In which of the following numbered sections of the lymph node does this B cell differentiation and proliferation most likely occur?", "answer": "3", "options": {"A": "1", "B": "2", "C": "3", "D": "4", "E": "5"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 73-year-old woman is brought to the physician by her son because of increasing forgetfulness over the past 2 years. Initially, she used to misplace keys and forget her dog's name or her phone number. Now, she often forgets about what she has seen on television or read about the day before. She used to go for a walk every morning but stopped one month ago after she became lost on her way back home. Her son has prevented her from cooking because she has had episodes of leaving the gas stove oven on after making a meal. She becomes agitated when asked questions directly but is unconcerned when her son reports her history and says he is overprotective of her. She has hypertension, coronary artery disease, and hypercholesterolemia. Current medications include aspirin, enalapril, carvedilol, and atorvastatin. She is alert and oriented to place and person but not to time. Vital signs are within normal limits. Short- and long-term memory deficits are present. Her speech rhythm is normal but is frequently interrupted as she thinks of words to frame her sentences. She makes multiple errors while performing serial sevens. Her clock drawing is impaired and she draws 14 numbers. Which of the following is the most likely diagnosis?", "answer": "Alzheimer disease", "options": {"A": "Normal pressure hydrocephalus", "B": "Lewy-body dementia", "C": "Frontotemporal dementia", "D": "Creutzfeld-Jakob disease", "E": "Alzheimer disease"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old woman is brought to the emergency department by her husband because of an episode of hematemesis 2 hours ago. She has had dyspepsia for 2 years. Her medications include occasional ibuprofen for headaches. After initial stabilization, the risks and benefits of upper endoscopy and alternative treatments, including no therapy, are explained thoroughly. She shows a good understanding of her condition and an appreciation of endoscopic treatment and its complications. She decides that she wants to have an endoscopy to find the source of bleeding and appropriately manage the ulcer. Her medical records show advance directives that she signed 3 years ago; her sister, who is a nurse, has a durable power of attorney. Regarding obtaining informed consent, which of the following is the most accurate conclusion for providing endoscopic treatment for this patient?", "answer": "Documentation of her decision prior to treatment is required", "options": {"A": "Documentation of her decision prior to treatment is required", "B": "Endoscopic treatment may be performed without further action", "C": "Her decision to have an endoscopy is not voluntary", "D": "Her sister must sign the consent form", "E": "There are reasons to believe that she may not have decision-making capacity"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old man is admitted to the hospital after a severe motor vehicle accident as an unrestrained front-seat passenger. Appropriate life-saving measures are given, and the patient is now hemodynamically stable. Physical examination shows a complete loss of consciousness. There are no motor or ocular movements with painful stimuli. The patient has bilaterally intact pupillary light reflexes. The patient is placed in a 30° semi-recumbent position for further examination. What is the most likely finding on the examination of this patient's right ear?", "answer": "Warm water causing ipsilateral saccadic movement.", "options": {"A": "Cold water causing ipsilateral saccadic movement.", "B": "Warm water causing ipsilateral slow pursuit.", "C": "Warm water causing ipsilateral saccadic movement.", "D": "Warm water mimicking the head turning left.", "E": "Cold water causing contralateral slow pursuit."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old man presents to the emergency department with palpitations. He also feels that his exercise tolerance has reduced over the previous week. His past history is positive for ischemic heart disease and he has been on multiple medications for a long time. On physical examination, his temperature is 36.9°C (98.4°F), pulse rate is 152/min and is regular, blood pressure is 114/80 mm Hg, and respiratory rate is 18/min. Auscultation of the precordial region confirms tachycardia, but there is no murmur or extra heart sounds. His ECG is obtained, which suggests a diagnosis of atrial flutter. Which of the following findings is most likely to be present on his electrocardiogram?", "answer": "Atrioventricular block", "options": {"A": "Atrial rate above 400 beats per minute", "B": "Slurred upstroke of R wave", "C": "Atrioventricular block", "D": "No discernible P waves", "E": "Wenckebach phenomenon"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man presents to the physician with a cough which he has had for the last 5 years. He also mentions that he has been feeling breathless when playing any active sport for the last 1 year. He is a manager in a corporate company and has been a regular smoker for 10 years. He has visited multiple physicians and undergone multiple diagnostic evaluations, without permanent benefit. On physical examination his temperature is 37.0°C (98.6°F), the heart rate is 88/min, the blood pressure is 122/80 mm Hg, and the respiratory rate is 20/min. Inspection suggests a barrel chest and auscultation reveals the presence of bilateral end-expiratory wheezing and scattered rhonchi. He undergoes a detailed diagnostic evaluation which includes a complete blood count, chest radiogram, arterial blood gas analysis, and pulmonary function tests, all of which confirm a diagnosis of chronic obstructive lung disease. After analyzing all the clinical information and diagnostic workup, the physician differentiates between emphysema and chronic bronchitis based on a single clue. Which of the following is the most likely clue that helped the physician in making the differential diagnosis?", "answer": "Decreased diffusion capacity of the lung for carbon monoxide (DLCO)", "options": {"A": "History of long-term exposure to cigarette smoke", "B": "Increased hematocrit in hematologic evaluation", "C": "Flattened diaphragm on chest X-ray", "D": "Presence of chronic respiratory acidosis in arterial blood gas analysis", "E": "Decreased diffusion capacity of the lung for carbon monoxide (DLCO)"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old male is rushed to the emergency department after sustaining several gunshot wounds to the chest. He was found nonresponsive in the field and was intubated en route to the hospital. His vital signs are as follows: temperature is 98.8 deg F (37.1 deg C), blood pressure is 87/52 mmHg, pulse is 120/min, and respirations are 16/min. Physical examination is significant for decreased breath sounds and dullness to percussion over the right lung. A chest radiograph in the emergency department shows a large fluid collection in the right thoracic cavity. After aggressive fluid resuscitation is initiated, an emergent chest-tube was placed in the emergency department. The chest tube puts out 700 cc of frank blood and 300 cc/hr over the next 5 hours. A follow up post-chest tube insertion chest radiograph demonstrates significant residual right hemothorax. Which of the following is the next best step in management of this patient?", "answer": "Open thoracotomy", "options": {"A": "Clamp the chest tube", "B": "Place the chest tube to water seal", "C": "Remove the chest tube", "D": "Open thoracotomy", "E": "Tracheostomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old is brought into your office by his mother. His mother states that he is having 10-20 episodes per day where he stops responding to his mother and is found staring out of the window. During these periods, he blinks more frequently than normal, but returns to his normal self afterwards. These episodes last 30 to 60 seconds. His mother states that all of his milestones have been normal and he had an uncomplicated birth. His mother also denies any other recent illness. On exam, his vitals are normal. During one of these episodes in the office, his EEG shows three-per-second spike and wave discharge. What is the most likely diagnosis?", "answer": "Absence seizure", "options": {"A": "Febrile seizure", "B": "Benign focal epilepsy", "C": "Juvenile myoclonic epilepsy", "D": "Absence seizure", "E": "Hearing deficits"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 19-year-old woman presents to the ED after multiple episodes of vomiting in the last 6 hours. The vomitus is non-bloody and non-bilious. The vomiting started shortly after she began having a throbbing, unilateral headache and associated photophobia. She has had several similar headaches in the past. Her vital signs are unremarkable. Which of the following is an appropriate therapy for this patient's vomiting?", "answer": "Chlorpromazine", "options": {"A": "Propranolol", "B": "Amitriptyline", "C": "Ergonovine", "D": "Chlorpromazine", "E": "Calcium channel blockers"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old woman is brought to the emergency department by her roommate for unusual behavior. They were at a party where alcohol and recreational drugs were consumed, but her roommate is unsure of what she may have taken or had to drink. She is otherwise healthy and does not take any medications. The patient appears anxious. Her temperature is 37.5°C (99.5°F), pulse is 110/min, respiratory rate is 16/min, and blood pressure is 145/82 mmHg. Examination shows dry mucous membranes and bilateral conjunctival injection. Breath sounds are normal. The abdomen is soft and nontender. Further evaluation will most likely reveal which of the following?", "answer": "Impaired reaction time", "options": {"A": "Respiratory depression", "B": "Decreased appetite", "C": "Increased libido", "D": "Pupillary constriction", "E": "Impaired reaction time"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old woman presents to her primary care physician for her annual check-up. She has no current complaints and says that she has been healthy over the last year. Her past medical history is significant for obesity and diabetes that is well controlled on metformin. She does not smoke and drinks socially. Selected lab results are shown below:\n\nHigh-density lipoprotein: 48 mg/dL\nLow-density lipoprotein: 192 mg/dL\nTriglycerides: 138 mg/dL\n\nGiven these results, the patient is placed on the drug that will be the best therapy for these findings. Which of the following is a potential side effect of this treatment?", "answer": "Hepatotoxicity", "options": {"A": "Gallstones", "B": "Gastrointestinal upset", "C": "Hepatotoxicity", "D": "Malabsorption", "E": "Pruritus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 67-year-old man presents to his primary care physician for fatigue. This has persisted for the past several months and has been steadily worsening. The patient has a past medical history of hypertension and diabetes; however, he is not currently taking any medications and does not frequently visit his physician. The patient has lost 20 pounds since his last visit. His laboratory values are shown below:\n\nHemoglobin: 9 g/dL\nHematocrit: 29%\nMean corpuscular volume: 90 µm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nCa2+: 11.8 mg/dL\n\nWhich of the following is the most likely diagnosis?", "answer": "Malignancy", "options": {"A": "Bone marrow aplasia", "B": "Intravascular hemolysis", "C": "Iron deficiency", "D": "Malignancy", "E": "Vitamin B12 and folate deficiency"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 19-year-old male soccer player undergoes an exercise tolerance test to measure his maximal oxygen uptake during exercise. Which of the following changes are most likely to occur during exercise?", "answer": "Decreased physiologic dead space", "options": {"A": "Increased pulmonary vascular resistance", "B": "Decreased physiologic dead space", "C": "Decreased alveolar-arterial oxygen gradient", "D": "Increased arterial partial pressure of oxygen", "E": "Increased apical ventilation-perfusion ratio"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old Caucasian female presents with Parkinson-like symptoms. Serum analysis shows increased levels of free copper and elevated liver enzymes. What test would prove most helpful in diagnosing the patient's underlying disease?", "answer": "Slit lamp examination", "options": {"A": "Serum detection of anti-myelin antibodies", "B": "Slit lamp examination", "C": "Vitamin B12 test", "D": "CT scan", "E": "Reflex test"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old male comes to the emergency department because of a 3-day history of intermittent shortness of breath and palpitations. The episodes are unprovoked and occur randomly. The day before, he felt lightheaded while walking and had to sit down abruptly to keep from passing out. He has hypertension and coronary artery disease. Cardiac catheterization 5 years ago showed occlusion of the left anterior descending artery, and he underwent placement of a stent. Current medications include aspirin, metoprolol, lisinopril, and clopidogrel. He does not drink alcohol or use any illicit drugs. He has smoked one-half pack of cigarettes daily for 20 years. He appears well. His temperature is 37°C (98.6°F), pulse is 136/min, respirations are 18/min, and blood pressure is 110/85 mm Hg. The lungs are clear to auscultation. Cardiac examination shows a rapid, irregular rhythm. Shortly after, an ECG is performed. Which of the following is the most likely cause of this patient's findings?", "answer": "Degeneration of sinoatrial node automaticity", "options": {"A": "Premature ventricular contractions", "B": "Abnormal automaticity within the ventricle", "C": "Degeneration of sinoatrial node automaticity", "D": "Dissociation of the atria and ventricles", "E": "Wandering atrial pacemaker"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman presents to her primary care doctor complaining of increased fatigue and cold intolerance after her recent delivery. The patient delivered a healthy 39-week-old boy 3 weeks ago via spontaneous vaginal delivery. Delivery was complicated by postpartum hemorrhage requiring admission to the intensive care unit with blood transfusions. Pregnancy was otherwise uneventful, and the baby is healthy. The mother has had some difficulty with lactation, but is able to supplement her breast milk with formula feeds. On exam, her temperature is 97.7°F (36.5°C), blood pressure is 112/78 mmHg, pulse is 62/min, and respirations are 12/min. The patient does not have any neck masses or lymphadenopathy; however, her skin appears dry and rough. Which of the following serum lab abnormalities may be expected?", "answer": "Decreased prolactin", "options": {"A": "Decreased prolactin", "B": "Decreased thyroid releasing hormone", "C": "Increased follicle stimulating hormone", "D": "Increased glucocorticoids", "E": "Increased luteinizing hormone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman comes to the physician because of progressively worsening joint pain. She has had diffuse, aching pain in her knees, shoulders, and hands bilaterally for the past few months, but the pain has become much more severe in the past few weeks. She also reports night sweats and generalized malaise. On physical examination, radial and pedal pulses are weak. There are erythematous nodules over the legs that measure 3–5 cm. Laboratory studies show:\nHematocrit 33.2%\nHemoglobin 10.7 g/dL\nLeukocyte count 11,300/mm3\nPlatelet count 615,000/mm3\nErythrocyte sedimentation rate 94 mm/h\nSerum\nC-reactive protein 40 mg/dL (N=0.08–3.1)\nWhich of the following is the most likely diagnosis?\"", "answer": "Takayasu arteritis", "options": {"A": "Temporal arteritis", "B": "Polyarteritis nodosa", "C": "Microscopic polyangiitis", "D": "Thromboangiitis obliterans", "E": "Takayasu arteritis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 19-year-old college student is brought to the emergency department with persistent vomiting overnight. He spent all day drinking beer yesterday at a college party according to his friends. He appears to be in shock and when asked about vomiting, he says that he vomited up blood about an hour ago. At the hospital, his vomit contains streaks of blood. His temperature is 37°C (98.6°F), respirations are 15/min, pulse is 107/min, and blood pressure is 90/68 mm Hg. A physical examination is performed and is within normal limits. Intravenous fluids are started and a blood sample is drawn for typing and cross-matching. An immediate upper gastrointestinal endoscopy reveals a longitudinal mucosal tear in the distal esophagus. What is the most likely diagnosis?", "answer": "Mallory-Weiss tear", "options": {"A": "Boerhaave syndrome", "B": "Mallory-Weiss tear", "C": "Pill esophagitis", "D": "Esophageal candidiasis", "E": "Dieulafoy's lesion"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old woman presents to her primary care physician with a 2-month history of joint pain and morning stiffness that improves through the course of the day. Her left knee also sometimes bothers her. She has taken ibuprofen and tylenol without relief, and the pain is starting to upset her daily routine. On physical examination, the joints of her fingers and wrists are swollen and tender to touch. Her left knee also feels warm. The strength in both hands is reduced but the sensation is intact. On auscultation, the heart sounds are regular and the lungs are clear. Laboratory findings are presented below:\nHemoglobin 12.7 g/dL\nHematocrit 37.5%   \nLeukocyte count 5,500/mm3\nMean corpuscular volume 82.2 μm3\nPlatelet count 190,000/mm3\nErythrocyte sedimentation rate 45 mm/h\nC-reactive protein        14 mg/dL\nAnti-citrullinated protein antibody 43 (normal reference values: < 20)\nWhich of the following is the most appropriate treatment for this patient?", "answer": "Methotrexate", "options": {"A": "Ibuprofen", "B": "Hydroxychloroquine", "C": "Infliximab", "D": "Methotrexate", "E": "Etanercept"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 6-year-old boy is brought to the pediatrician by his foster father because he is concerned about the boy's health. He states that at seemingly random times he will have episodes of severe difficulty breathing and wheezing. Upon questioning, the pediatrician learns that these episodes do not appear to be associated with exercise, irritants, or infection. The pediatrician suspects the child has a type of asthma that is associated with eosinophils. In this type of asthma, what is released by the eosinophils to cause bronchial epithelial damage?", "answer": "Major basic protein", "options": {"A": "IL-5", "B": "Major basic protein", "C": "IgM", "D": "IL-8", "E": "Interferon-gamma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old man presents with fever, chills, fatigue, cough, sore throat, and breathlessness for the past 7 days. He describes the cough as productive and says he is fatigued all the time. He says he is a farmer with daily contact with rabbits, horses, sheep, pigeons, and chickens and reports cleaning the barn 3 days before his symptoms started. The patient denies any history of tick bites. Past medical history is irrelevant. His temperature is 39.4°C (103.0°F), pulse is 110/min, and respirations are 26/min. On physical examination, there are decreased breath sounds on the right side. A large tender node is palpable in the right axilla. A chest radiograph reveals multiple homogenous opacities in the lower lobe of the right lung and a right-sided pleural effusions. Gram staining of a sputum sample is negative for any organism. Serology tests are negative. Which of the following is the most likely causative organism for this patient’s condition?", "answer": "Francisella tularensis", "options": {"A": "Francisella tularensis", "B": "Bacillus anthracis", "C": "Staphylococcus aureus ", "D": "Yersinia pestis", "E": "Mycoplasma pneumoniae"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Two days after undergoing an uncomplicated total thyroidectomy, a 63-year-old woman has acute, progressive chest pain. The pain is sharp and burning. She feels nauseated and short of breath. The patient has a history of hypertension, type 1 diabetes mellitus, medullary thyroid cancer, multiple endocrine neoplasia type 2A, anxiety, coronary artery disease, and gastroesophageal reflux disease. She smoked half a pack of cigarettes daily for 24 years but quit 18 years ago. Current medications include lisinopril, insulin glargine, insulin aspart, sertraline, aspirin, ranitidine, and levothyroxine. She appears anxious and diaphoretic. Her temperature is 37.4°C (99.3°F), pulse is 64/min, respirations are 17/min, and blood pressure is 148/77 mm Hg. The lungs are clear to auscultation. Examination shows a 3-cm linear incision over the anterior neck with 1 mm of surrounding erythema and mild serous discharge. The chest wall and abdomen are nontender. There is 5/5 strength in all extremities and decreased sensation to soft touch on the feet bilaterally. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Obtain an ECG and troponin T levels", "options": {"A": "Obtain an ECG and troponin T levels", "B": "Administer IV pantoprazole and schedule endoscopy", "C": "Discontinue levothyroxine and obtain fT4 levels", "D": "Administer IV levofloxacin and obtain chest radiograph", "E": "Obtain urine and plasma metanephrine levels"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A young researcher is studying the structure of class I and class II major histocompatibility complex (MHC) molecules. He understands that these molecules are proteins, but the structures of class I MHC molecules are different from those of class II. Although all these molecules consist of α and β chains, some of their domains are polymorphic, meaning they are different in different individuals. He calls them ‘P’ domains. The other domains are nonpolymorphic, which remain invariant in all individuals. He calls these domains ‘N’ domains. Which of the following are examples of ‘N’ domains?", "answer": "α3 domain in class I molecules and β2 domain in class II molecules", "options": {"A": "β2-microglobulin in class I molecules and β1 domain in class II molecules", "B": "α1 domain in class I molecules and α1 domain in class II molecules", "C": "α2 domain in class I molecules and β2 domain in class II molecules", "D": "α1-α2 domains in class I molecules and α1-β1 domains in class II molecules", "E": "α3 domain in class I molecules and β2 domain in class II molecules"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old boy is brought to the physician by his mother because of increasingly withdrawn behavior for the last two years. His mother reports that in the last 2–3 years of high school, her son has spent most of his time in his room playing video games. He does not have any friends and has never had a girlfriend. He usually refuses to attend family dinner and avoids contact with his siblings. The patient states that he prefers being on his own. When asked how much playing video games means to him, he replies that “it's okay.” When his mother starts crying during the visit, he appears indifferent. Physical and neurologic examinations show no other abnormalities. On mental status examination, his thought process is organized and logical. His affect is flattened. Which of the following is the most likely diagnosis?", "answer": "Schizoid personality disorder", "options": {"A": "Schizophreniform disorder", "B": "Schizoid personality disorder", "C": "Antisocial personality disorder", "D": "Avoidant personality disorder", "E": "Paranoid personality disorder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old man presents with an oral cavity lesion, toothache, and weight loss. He is known to have been HIV-positive for 6 years, but he does not follow a prescribed antiretroviral regimen because of personal beliefs. The vital signs are as follows: blood pressure 110/80 mm Hg, heart rate 89/min, respiratory rate 17/min, and temperature 37.1°C (100.8°F). The physical examination revealed an ulcerative lesion located on the lower lip. The lesion was friable, as evidenced by contact bleeding, and tender on palpation. A CT scan showed the lesion to be a solid mass (7 x 6 x 7 cm3) invading the mandible and spreading to the soft tissues of the oral cavity floor. A biopsy was obtained to determine the tumor type, which showed a monotonous diffuse lymphoid proliferation of large cells with plasmablastic differentiation, and oval-to-round vesicular nuclei with fine chromatin. The cells are immunopositive for VS38c. DNA of which of the following viruses is most likely to be identified in the tumor cells?", "answer": "EBV", "options": {"A": "CMV", "B": "EBV", "C": "HHV-8", "D": "HHV-1", "E": "HPV-16"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year old man comes to his physician because of a 1-month history of increased thirst and nocturia. He is drinking a lot of water to compensate for any dehydration. His brother has type 2 diabetes mellitus. Physical examination shows dry mucous membranes. Laboratory studies show a serum sodium of 151 mEq/L and glucose of 121 mg/dL. A water deprivation test shows:\nSerum osmolality\n(mOsmol/kg H2O) Urine osmolality\n(mOsmol/kg H2O)\nInitial presentation 295 285\nAfter 3 hours without fluids 305 310\nAfter administration of antidiuretic hormone (ADH) analog 280 355\nWhich of the following is the most likely diagnosis?\"", "answer": "Partial central diabetes inspidus", "options": {"A": "Nephrogenic diabetes insipidus", "B": "Partial central diabetes inspidus", "C": "Complete central diabetes insipidus", "D": "Primary polydipsia", "E": "Osmotic diuresis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 13-year-old girl is brought to the physician by her parents because of a 2-day history of low-grade fever, headache, nausea, and a sore throat. Examination of the oral cavity shows enlarged, erythematous tonsils with exudates and palatal petechiae. There is cervical lymphadenopathy. Her parents agree to her participating in a study of microbial virulence factors. A culture of the girl's throat is obtained and an organism is cultivated. The physician finds that the isolated organism is able to withstand phagocytosis when placed in fresh blood. The most likely explanation for this finding is the expression of which of the following?", "answer": "M Protein", "options": {"A": "IgA protease", "B": "Protein A", "C": "Streptolysin O", "D": "Hyaluronidase", "E": "M Protein"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old man comes to the physician for the evaluation of episodic headaches for 5 months. The headaches involve both temples and are 4/10 in intensity. The patient has been taking acetaminophen, but the headaches did not subside. He has also had visual disturbances, including double vision. He has no nausea, temperature intolerance, or weight changes. The patient does not smoke. He drinks 2–3 beers on weekends. He appears pale. His temperature is 37°C (98.6°F), pulse is 75/min, and blood pressure 125/80 mm Hg. Ophthalmologic examination shows impaired peripheral vision bilaterally. An MRI scan of the head with contrast shows a 16 × 11 × 9 mm intrasellar mass. Further evaluation is most likely to show which of the following findings?", "answer": "Erectile dysfunction", "options": {"A": "Galactorrhea", "B": "Coarse facial features", "C": "Diffuse goiter", "D": "Erectile dysfunction", "E": "Abdominal striae"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy is brought to the physician because of frequent falls, worsening muscle pain, and poor vision in low light conditions. His mother reports that he has been on a low-fat diet since infancy because of persistent diarrhea. He is at the 5th percentile for height and weight. Physical examination shows bilateral proximal muscle weakness and a wide ataxic gait. His serum cholesterol level is 21 mg/dL. Peripheral blood smear shows red blood cells with irregular spiny projections of varying size. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Post-prandial lipid-laden enterocytes", "options": {"A": "GAA trinucleotide repeats on chromosome 9", "B": "Post-prandial lipid-laden enterocytes", "C": "Sweat chloride levels > 60 mmol/L", "D": "IgA anti-tissue transglutaminase antibodies", "E": "Fibrofatty replacement of muscle tissue"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man presents to his primary care physician complaining of a blistering rash in his inguinal region. Upon further questioning, he also endorses an unintended weight loss, diarrhea, polydipsia, and polyuria. A fingerstick glucose test shows elevated glucose even though this patient has no previous history of diabetes. After referral to an endocrinologist, the patient is found to have elevated serum glucagon and is diagnosed with glucagonoma. Which of the following is a function of glucagon?", "answer": "Increased lipolysis", "options": {"A": "Inhibition of insulin release", "B": "Increased glycolysis", "C": "Decreased glycogenolysis", "D": "Increased lipolysis", "E": "Decreased ketone body producttion"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old woman is brought to the emergency department because of 3 1-hour episodes of severe, sharp, penetrating abdominal pain in the right upper quadrant. During these episodes, she had nausea and vomiting. She has no diarrhea, dysuria, or hematuria and is asymptomatic between episodes. She has hypertension and hyperlipidemia. Seven years ago, she underwent resection of the terminal ileum because of severe Crohn's disease. She is 155 cm (5 ft 2 in) tall and weighs 79 kg (175 lb). Her BMI is 32 kg/m2. Her temperature is 36.9°C (98.5°F), pulse is 80/min, and blood pressure is 130/95 mm Hg. There is mild scleral icterus. Cardiopulmonary examination shows no abnormalities. The abdomen is soft, and there is tenderness to palpation of the right upper quadrant without guarding or rebound. Bowel sounds are normal. The stool is brown, and a test for occult blood is negative. Laboratory studies show:\nLaboratory test\nBlood  \nHemoglobin 12.5 g/dL\nLeukocyte count 9,500 mm3\nPlatelet count 170,000 mm3\nSerum  \nTotal bilirubin 4.1 mg/dL\nAlkaline phosphatase 348 U/L\nAST 187 U/L\nALT 260 U/L\nAbdominal ultrasonography shows a normal liver, a common bile duct caliber of 10 mm (normal < 6 mm), and gallbladder with multiple gallstones and no wall thickening or pericholecystic fluid. Which of the following is the most likely cause of these findings?", "answer": "Choledocholithiasis", "options": {"A": "Acute hepatitis A", "B": "Cholangitis", "C": "Cholecystitis", "D": "Choledocholithiasis", "E": "Pancreatitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "In a recently conducted case-control study that aimed to elucidate the causes of myelomeningocele (a neural tube defect in which there is an incomplete formation of the spinal bones), 200 mothers of infants born with the disease and 200 mothers of infants born without the disease were included in the study. Among the mothers of infants with myelomeningocele, 50% reported having experienced pharyngitis (sore throat) during pregnancy, compared with 5% of the mothers whose infants did not develop the condition. The researchers concluded that there is an association between pharyngitis during pregnancy and myelomeningocele; this conclusion was backed up by statistical analysis of the obtained results. Which type of bias may hamper the validity of the researchers’ conclusions?", "answer": "Recall bias", "options": {"A": "Surveillance bias", "B": "Attrition bias", "C": "Recall bias", "D": "Assessment bias", "E": "Neyman bias"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 66-year-old woman presents to the primary care physician with complaints of involuntary loss of urine. This has been occurring over the past month for no apparent reason while suddenly feeling the need to urinate. History reveals triggers that stimulate the desire to pass urine, such as running water, handwashing, and cold weather. There is no family history of similar symptoms in her mother or any of her 8 children. Her blood pressure is 130/80 mm Hg, heart rate is 72/min, respiratory rate is 22/min, and temperature is 36.6°C (98.0°F). Physical examination is unremarkable. Urinalysis reveals the following:\nColor Yellow\nClarity/turbidity Clear\npH 5.5\nSpecific gravity 1.015\nNitrites Negative\nLeukocyte esterase Negative\nWhich of the following is the best next step in the management of this patient?", "answer": "Bladder training", "options": {"A": "Administer antimuscarinics", "B": "Bladder training", "C": "Administer antibiotics", "D": "Posterior tibial nerve stimulation", "E": "Surgery"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old woman with a recent history of carcinoma of the breast status post mastectomy and adjuvant chemotherapy one week ago presents for follow-up. She reports adequate pain control managed with the analgesic drug she was prescribed. Past medical history is significant for hepatitis C and major depressive disorder. The patient denies any history of smoking or alcohol use but says she is currently using intravenous heroin and has been for the past 10 years. However, she reports that she has been using much less heroin since she started taking the pain medication, which is confirmed by the toxicology screen. Which of the following is the primary mechanism of action of the analgesic drug she was most likely prescribed?", "answer": "Mixed agonist-antagonist at opioid receptors", "options": {"A": "Mixed agonist-antagonist at opioid receptors", "B": "Pure antagonist at opioid receptors", "C": "Inhibits prostaglandin synthesis", "D": "Pure agonist at the µ-opioid receptor", "E": "Central action via blockade of serotonin reuptake"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old man is brought to the emergency department by ambulance from a homeless shelter. The report from the shelter describes the man as a loner expressing symptoms of depression. He has been living at the shelter for approximately 10 months and has no family or friends and few visitors. He spends most of his evenings drinking alcohol and being by himself. Which of the following statements is most accurate regarding this patient?", "answer": "Males are more likely to die from suicide than females.", "options": {"A": "Males are more likely to die from suicide than females.", "B": "Males attempt suicide more than females.", "C": "Males are more likely to use drug overdose as a means of suicide.", "D": "Females are more likely to self-inflict fatal injuries.", "E": "Suicide risk is highest among middle-age white women."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man with a history of hypertension visits your office. His blood pressure on physical examination is found to be 150/90. You prescribe him metoprolol. Which of the following do you expect to occur as a result of the drug?", "answer": "Decreased serum renin levels as a consequence of ß1 receptor antagonism", "options": {"A": "Decreased PR interval on EKG", "B": "Decreased serum renin levels as consequence of ß2 antagonism", "C": "Increased serum renin levels as a consequence of ß2 receptor antagonism", "D": "Decreased serum renin levels as a consequence of ß1 receptor antagonism", "E": "Increased serum renin levels as a consequence of ß1 receptor antagonism"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought to the physician because of a nonpruritic rash on his face that began 5 days ago. It started as a bug bite on his chin that then developed into small pustules with surrounding redness. He has not yet received any routine childhood vaccinations. Physical examination shows small, clustered lesions with gold crusts along the lower lip and chin and submandibular lymphadenopathy. At a follow-up examination 2 weeks later, his serum anti-deoxyribonuclease B antibody titer is elevated. This patient is at greatest risk for which of the following complications?", "answer": "Glomerulonephritis", "options": {"A": "Reactive arthritis", "B": "Shingles", "C": "Glomerulonephritis", "D": "Orchitis", "E": "Myocarditis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 29-year-old G2P1 woman presents at 24 weeks gestation with complaints of blurred vision and headaches. Her symptoms have increased in frequency over the past several weeks. Her medical history is significant only for occasional tension headaches. She takes no medications besides an oral folic acid supplement. The vital signs are: blood pressure, 159/90 mm Hg; pulse, 89/min; and respiratory rate, 18/min. She is afebrile. She states that her husband, a nurse, took her blood pressure 2 days earlier and found it to be 154/96 mm Hg at the time. Previously, her blood pressures have always been < 120/80 mm Hg. What is the next best step to solidify the diagnosis?", "answer": "24-hour urine collection", "options": {"A": "Electrocardiogram", "B": "Non-contrast enhanced head CT", "C": "Serum CBC and electrolytes", "D": "24-hour urine collection", "E": "Fetal ultrasound"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old male presents to the emergency room for toe pain. He reports that his right great toe became acutely painful, red, and swollen approximately five hours prior. He has had one similar prior episode six months ago that resolved with indomethacin. His medical history is notable for obesity, hypertension, and alcohol abuse. He currently takes hydrochlorothiazide (HCTZ). On physical examination, his right great toe is swollen, erythematous, and exquisitely tender to light touch. The patient is started on a new medication that decreases leukocyte migration and mitosis, and his pain eventually resolves; however, he develops nausea and vomiting as a result of therapy. Which of the following underlying mechanisms of action is characteristic of this patient’s new medication?", "answer": "Inhibits microtubule polymerization", "options": {"A": "Inhibits microtubule polymerization", "B": "Prevents conversion of xanthine to uric acid", "C": "Decreases phospholipase A2-induced production of arachidonic acid", "D": "Decreases cyclooxygenase-induced production of prostaglandins", "E": "Metabolizes uric acid to water-soluble allantoin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old man is referred to an endocrinologist for paroxysms of headaches associated with elevated blood pressure and palpitations. He is otherwise healthy, although he notes a family history of thyroid cancer. His physical examination is significant for the findings shown in Figures A, B, and C. His thyroid is normal in size, but there is a 2.5 cm nodule palpable in the right lobe. On further workup, it is found that he has elevated plasma-free metanephrines and a normal TSH. Fine-needle aspiration of the thyroid nodule stains positive for calcitonin. The endocrinologist suspects a genetic syndrome. What is the most likely inheritance pattern?", "answer": "Autosomal dominant", "options": {"A": "Autosomal dominant", "B": "Autosomal recessive", "C": "Mitochondrial", "D": "X-linked dominant", "E": "X-linked recessive"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 29-year-old man comes to the emergency department because of a 4-day history of abdominal pain and confusion. Prior to the onset of the abdominal pain, he visited a festival where he consumed large amounts of alcohol. Examination shows a distended abdomen, decreased bowel sounds, and diffuse tenderness to palpation. There is motor weakness in the upper extremities. Sensation is decreased over the upper and lower extremities. Laboratory studies show no abnormalities. Which of the following is the most appropriate therapy for this patient's condition?", "answer": "Hemin", "options": {"A": "Intravenous immunoglobulin", "B": "Hemin", "C": "Ethylenediaminetetraacetic acid", "D": "Chlordiazepoxide", "E": "Chloroquine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-year-old Caucasian male patient presents with recurrent infections. During examination of his CD4 T-cells, it is noticed that his T-cells lack CD40 ligand. Which type of immunoglobulin is likely to be present in excess?", "answer": "IgM", "options": {"A": "IgA", "B": "IgE", "C": "IgG", "D": "IgM", "E": "IgD"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old woman is in her last few months at community college. She has a very important essay due in 2 weeks that will play a big part in determining her final grades. She decides to focus on writing this essay instead and not to worry about her grades until her essay is completed. Which of the following defense mechanisms best explains her behavior?", "answer": "Suppression", "options": {"A": "Repression", "B": "Suppression", "C": "Blocking", "D": "Dissociation", "E": "Denial"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 93-year-old woman is brought to the physician because of a purple area on her right arm that has been growing for one month. She has not had any pain or itching of the area. She has hyperlipidemia, a history of basal cell carcinoma treated with Mohs surgery 2 years ago, and a history of invasive ductal carcinoma of the right breast treated with radical mastectomy 57 years ago. She has had chronic lymphedema of the right upper extremity since the mastectomy. Her only medication is simvastatin. She lives in an assisted living facility. She is content with her living arrangement but feels guilty that she is dependent on others. Vital signs are within normal limits. Physical examination shows extensive edema of the right arm. Skin exam of the proximal upper right extremity shows three coalescing, 0.5–1.0 cm heterogeneous, purple-colored plaques with associated ulceration. Which of the following is the most likely diagnosis?", "answer": "Lymphangiosarcoma", "options": {"A": "Lymphangiosarcoma", "B": "Cellulitis", "C": "Thrombophlebitis", "D": "Lichen planus", "E": "Kaposi sarcoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A boy born vaginally in the 36th week of gestation to a 19-year-old woman (gravida 3, para 1) is assessed on his 2nd day of life. His vitals include: blood pressure is 85/40 mm Hg, pulse is 161/min, axillary temperature is 36.6°C (98.0°F), and respiratory rate is 44/min. He appears to be lethargic; his skin is jaundiced and slight acrocyanosis with several petechiae is noted. Physical examination reveals nystagmus, muffled heart sounds with a continuous murmur, and hepatosplenomegaly. The boy’s birth weight is 1.93 kg (4.25 lb) and Apgar scores at the 1st and 5th minutes were 5 and 8, respectively. His mother is unaware of her immunization status and did not receive any antenatal care. She denies any history of infection, medication use, or alcohol or illicit substance use during pregnancy. Serology for suspected congenital TORCH infection shows the following results:\nAnti-toxoplasma gondii IgM Negative\nAnti-toxoplasma gondii IgG Positive\nAnti-CMV IgM Negative\nAnti-CMV IgG Positive\nAnti-Rubella IgM Positive\nAnti-Rubella IgG Positive\nAnti-HSV IgM Negative\nAnti-HSV IgG Negative\nWhich cardiac abnormality would be expected in this infant on echocardiography?", "answer": "Patent ductus arteriosus", "options": {"A": "Pulmonary valve stenosis", "B": "Patent ductus arteriosus", "C": "Ventricular septal defect", "D": "Atrial septal defect", "E": "Atrialization of the right ventricle"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman presents to the emergency department with severe abdominal pain. She states that the pain has been dull and progressive, but became suddenly worse while she was exercising. The patient's past medical history is notable for depression, anxiety, and gonococcal urethritis that was appropriately treated. The patient states that she is sexually active and does not use condoms. She admits to drinking at least 5 standard alcoholic drinks a day. The patient also recently lost a large amount of weight for a fitness show she planned on entering. The patient's current medications include oral contraceptive pills, fluoxetine, alprazolam, ibuprofen, acetaminophen, and folate. On physical exam you note an athletic young woman with burly shoulders, a thick neck, and acne on her forehead and back. On abdominal exam you note diffuse tenderness with 10/10 pain upon palpation of the right upper quadrant. Blood pressure is 80/40 mmHg, pulse is 110/minute, temperature is 99.5°F (37.5°C) and respirations are 15/minute with an oxygen saturation of 96% on room air. Intravenous fluids are started and labs are sent. A urinary ß-hCG has been ordered. Which of the following is most likely the diagnosis?", "answer": "Vascular ectasia within the liver", "options": {"A": "Obstruction of the common bile duct by radio-opaque stones", "B": "Obstruction of blood flow through the hepatic vein", "C": "Vascular ectasia within the liver", "D": "Ectopic implantation of a blastocyst", "E": "Inflammation of the pancreas"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old immigrant presents to his primary care physician for a general checkup. This is his first time visiting a physician, and he has no known past medical history. The patient’s caretaker states that the patient has experienced episodes of syncope and what seems to be seizures before but has not received treatment. His temperature is 98.1°F (36.7°C), blood pressure is 121/83 mmHg, pulse is 83/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam is notable for sensorineural deafness. Which of the following ECG changes is most likely to be seen in this patient?", "answer": "Prolonged QT interval", "options": {"A": "Increased voltages", "B": "Peaked T waves", "C": "Prolonged QRS interval", "D": "Prolonged QT interval", "E": "QT shortening"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old nulliparous woman is found upon transthoracic echocardiography to have a dilated aorta and mitral valve prolapse. The patient has a history of joint pain, and physical examination reveals pectus excavatum and stretch marks on the skin. She does not take any medications and has no history of past drug use. The patient’s findings are most likely associated with which of the following underlying diagnoses?", "answer": "Marfan syndrome", "options": {"A": "Ehlers-Danlos syndrome", "B": "Turner syndrome", "C": "DiGeorge syndrome", "D": "Friedrich’s ataxia", "E": "Marfan syndrome"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old woman comes to the physician with fever and malaise. For the past 2 days, she has felt fatigued and weak and has had chills. Last night, she had a temperature of 40.8°C (104.2°F). She has also had difficulty swallowing since this morning. The patient was recently diagnosed with Graves disease and started on methimazole. She appears uncomfortable. Her temperature is 38.3°C (100.9°F), pulse is 95/min, and blood pressure is 134/74 mm Hg. The oropharynx is erythematous without exudate. The lungs are clear to auscultation. Laboratory studies show:\nHematocrit 42%\nHemoglobin 13.4 g/dL\nLeukocyte count 3,200/mm3\nSegmented neutrophils 9%\nBasophils < 1%\nEosinophils < 1%\nLymphocytes 79%\nMonocytes 11%\nPlatelet count 230,000/mm3\nWhich of the following is the most appropriate next step in management?\"", "answer": "Discontinue methimazole", "options": {"A": "Bone marrow biopsy", "B": "Discontinue methimazole", "C": "Switch to propylthiouracil", "D": "Test for EBV, HIV, and CMV", "E": "Decrease methimazole dose"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-year-old refugee with delayed growth and weakness is brought to the physician. Her family has been displaced several times over the last few years, and nutrition and housing were frequently inadequate. Examination of the lower limbs shows bowing of the legs with reduced proximal muscle strength. The abdomen is protruded. Inspection of the chest shows subcostal grooving during inspiration. An image of the patient’s wrist is shown. Which of the following is the most likely cause of this patient’s condition?", "answer": "Vitamin D deficiency", "options": {"A": "Defective collagen synthesis", "B": "Insufficient protein consumption", "C": "Low-calorie intake", "D": "Osteoclast hyperactivity", "E": "Vitamin D deficiency"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 16-year-old boy presents with a long-standing history of anemia. Past medical history is significant for prolonged neonatal jaundice and multiple episodes of jaundice without fever. On physical examination, the patient shows generalized pallor, scleral icterus, and splenomegaly. His hemoglobin is 10 g/dL, and examination of a peripheral blood smear shows red cell basophilic stippling. Which of the following is the most likely diagnosis in this patient?", "answer": "Pyrimidine 5’-nucleotidase deficiency", "options": {"A": "Pyruvate kinase deficiency", "B": "Cytochrome b5 reductase deficiency", "C": "Lead poisoning", "D": "Pyrimidine 5’-nucleotidase deficiency", "E": "Glucose-6-phosphate dehydrogenase deficiency"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old woman with a history of poorly controlled asthma presents to her pulmonologist for a follow-up visit. She was recently hospitalized for an asthma exacerbation. It is her third hospitalization in the past five years. She currently takes inhaled salmeterol and medium-dose inhaled budesonide. Her past medical history is also notable for psoriasis. She does not smoke and does not drink alcohol. Her temperature is 98.6°F (37°C), blood pressure is 110/65 mmHg, pulse is 75/min, and respirations are 20/min. Physical examination reveals bilateral wheezes that are loudest at the bases. The patient’s physician decides to start the patient on zileuton. Which of the following is the most immediate downstream effect of initiating zileuton?", "answer": "Decreased production of leukotrienes", "options": {"A": "Decreased production of leukotrienes", "B": "Decreased signaling via the leukotriene receptor", "C": "Decreased IgE-mediated pro-inflammatory activity", "D": "Decreased mast cell degranulation", "E": "Decreased signaling via the muscarinic receptor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought to the emergency department with acute intermittent umbilical abdominal pain that began that morning. The pain radiates to his right lower abdomen and occurs every 15–30 minutes. During these episodes of pain, the boy draws up his knees to the chest. The patient has had several episodes of nonbilious vomiting. He had a similar episode 3 months ago. His temperature is 37.7°C (99.86°F), pulse is 99/min, respirations are 18/min, and blood pressure is 100/60 mm Hg. Abdominal examination shows periumbilical tenderness with no masses palpated. Abdominal ultrasound shows concentric rings of bowel in transverse section. Laboratory studies show:\nLeukocyte Count 8,000/mm3\nHemoglobin 10.6 g/dL\nHematocrit 32%\nPlatelet Count 180,000/mm3\nSerum\nSodium 143 mEq/L\nPotassium 3.7 mEq/L\nChloride 88 mEq/L\nBicarbonate 28 mEq/L\nUrea Nitrogen 19 mg/dL\nCreatinine 1.3 mg/dL\nWhich of the following is the most likely underlying cause of this patient's condition?\"", "answer": "Meckel diverticulum", "options": {"A": "Intestinal adhesions", "B": "Meckel diverticulum", "C": "Acute appendicitis", "D": "Malrotation with volvulus", "E": "Intestinal polyps\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A lung mass of a 50 pack-year smoker is biopsied. If ADH levels were grossly increased, what would most likely be the histologic appearance of this mass?", "answer": "Sheets of small round cells with hyperchromatic nuclei", "options": {"A": "Tall columnar cells bordering the alveolar septum", "B": "Sheets of small round cells with hyperchromatic nuclei", "C": "Layered squamous cells with keratin pearls", "D": "Hyperplasia of mucin producing glandular tissue", "E": "Pleomorphic giant cells with leukocyte fragments in cytoplasm"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old man presents to his primary care physician for a routine physical exam. He is concerned about a burning sensation that he feels in his throat whenever he eats large meals and is concerned he may have esophageal cancer like his uncle. The patient has a past medical history of irritable bowel syndrome and constipation. His current medications include whey protein supplements, fish oil, a multivitamin, and sodium docusate. The patient is concerned about his performance in school and fears he may fail out. He recently did poorly on an exam and it has caused him significant stress. He also is worried that his girlfriend is going to leave him. The patient claims that he thought he was going to be an incredible doctor some day, but now he feels like a terrible person. The patient also states that he feels guilty about his grandfather's death which occurred 1 year ago and he often reexperiences the funeral in his mind. He regularly has trouble sleeping for which he takes melatonin. The patient has been praying every 4 hours with the hopes that this will make things go better for him. Which of the following is the most likely diagnosis?", "answer": "Generalized anxiety disorder", "options": {"A": "Acute stress disorder", "B": "Depression", "C": "Generalized anxiety disorder", "D": "Obsessive compulsive disorder", "E": "Post traumatic stress disorder"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old man presents to the physician for a check-up as part of his immigration application. On auscultation, there is a mild rumble heard at the cardiac apex preceded by an opening snap. His blood pressure is 132/76 and heart rate is 78/min. The patient suffers from occasional asthma attacks but has noticed that he cannot hold his breath on exertion over the past 2 years. He is otherwise healthy. He does not recall if he had any serious infections during childhood, and there is no family history of congenital diseases. Which of the following could have been used to prevent the development of this condition?", "answer": "Penicillin", "options": {"A": "Penicillin", "B": "Alprostadil", "C": "Sulfasalazine", "D": "Indomethacin", "E": "PGE1 infusion"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 82-year-old woman is brought to the physician by her son because he is concerned about her forgetfulness for the past 2 years. She occasionally walks into a room and forgets why she went there and often forgets where she left her keys. She is sometimes unable to recall a familiar individual's name. She reports that she has become slower at completing sudoku puzzles. She has been living independently since the death of her husband 3 years ago. She goes shopping, cooks her own meals, and plays bridge with her friends every weekend. She is not anxious about her memory lapses. She has no trouble sleeping but has been getting up earlier than she used to. She has hypertension that is managed with hydrochlorothiazide. She appears healthy. Vital signs are within normal limits. She is oriented to person, place, and time. Examination shows a normal gait. She describes her mood as “good” and her speech is normal. Her thought process is organized and her judgement is intact. She makes one error when performing serial sevens. The remainder of the examination shows no abnormalities. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Aging", "options": {"A": "Aging", "B": "Alzheimer's disease", "C": "Lewy-body dementia", "D": "Vascular Dementia", "E": "Normal pressure hydrocephalus\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 40-year-old man comes to the physician because of fatigue, increased sweating, and itching in his legs for the past 2 years. He has chronic bronchitis. He has smoked two packs of cigarettes daily for 24 years and drinks one to two beers every night. His only medication is a tiotropium bromide inhaler. His vital signs are within normal limits. He is 175 cm (5 ft 9 in) tall and weighs 116 kg (256 lb); BMI is 38 kg/m2. Physical examination shows facial flushing and bluish discoloration of the lips. Scattered expiratory wheezing and rhonchi are heard throughout both lung fields. Abdominal examination shows no abnormalities. Laboratory studies show:\nErythrocyte count 6.9 million/mm3\nHemoglobin 20 g/dL\nMean corpuscular volume 91 μm3\nLeukocyte count 13,000/mm3\nPlatelet count 540,000/mm3\nSerum\nFerritin 8 ng/mL\nIron 48 μg/dL\nIron binding capacity 402 μg/dL (N: 251 - 406 μg/dL)\nWhich of the following is the most appropriate next step in treatment?\"", "answer": "Phlebotomy", "options": {"A": "Weight loss", "B": "Allogeneic stem cell transplantation", "C": "Hydroxyurea", "D": "Inhaled budesonide", "E": "Phlebotomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old woman comes to the clinic complaining of headache and sinus drainage for the past 13 days. She reports cold-like symptoms 2 weeks ago that progressively got worse. The patient endorses subjective fever, congestion, sinus headache, cough, and chills. She claims that this is her 5th episode within the past year and is concerned if “there’s something else going on.” Her medical history is significant for asthma that is adequately controlled with her albuterol inhaler. Her laboratory findings are shown below:\n\nSerum:\nHemoglobin: 16.2 g/dL\nHematocrit: 39 %\nLeukocyte count: 7,890/mm^3 with normal differential\nPlatelet count: 200,000/mm^3\nIgA: 54 mg/dL (Normal: 76-390 mg/dL)\nIgE: 0 IU/mL (Normal: 0-380 IU/mL)\nIgG: 470 mg/dL (Normal: 650-1500 mg/dL)\nIgM: 29 mg/dL (Normal: 40-345 mg/dL)\n\nWhat is the most likely diagnosis?", "answer": "Common variable immunodeficiency", "options": {"A": "Ataxia-telangiectasia", "B": "Common variable immunodeficiency", "C": "Selective IgA deficiency", "D": "Wiskott-Aldrich syndrome", "E": "X-linked agammaglobinemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old man presents to his primary care physician for a routine check-up. During the appointment, he remarks that he has started noticing some thinning and hair loss without other symptoms. The physician reassures him that he is likely experiencing male-pattern baldness and explains that the condition is largely inherited. Specifically he notes that there are multiple genes that are responsible for the condition so it is difficult to predict the timing and development of hair loss. What genetic principle is being illustrated by this scenario?", "answer": "Polygenic inheritance", "options": {"A": "Pleiotropy", "B": "Anticipation", "C": "Polygenic inheritance", "D": "Uniparental disomy", "E": "Heteroplasmy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 67-year-old man comes to the physician because of a 3-month history of difficulty initiating urination. He wakes up at least 3–4 times at night to urinate. Digital rectal examination shows a symmetrically enlarged, nontender prostate with a rubbery consistency. Laboratory studies show a prostate-specific antigen level of 2.1 ng/mL (N < 4). Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Hyperplasia of lateral prostatic lobe tissue", "options": {"A": "Hyperplasia of lateral prostatic lobe tissue", "B": "Infiltrating neoplasia of bladder urothelium", "C": "Hypertrophy of middle prostatic lobe tissue", "D": "Lymphocytic infiltration of anterior prostatic lobe stroma", "E": "Infiltrating dysplasia of posterior prostatic lobe epithelium"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2860-g (6-lb 3-oz) male newborn is born at term to a primigravid woman via spontaneous vaginal delivery. The mother has had no routine prenatal care. She reports that there is no family history of serious illness. The initial examination of the newborn shows bowing of the legs and respiratory distress upon palpation of the chest. The skin and joints are hyperextensible. X-rays of the chest and skull show multiple rib fractures and small, irregular bones along the cranial sutures. The patient is at increased risk of which of the following complications?", "answer": "Hearing loss", "options": {"A": "Costochondral junction enlargement", "B": "Intestinal rupture", "C": "Intellectual disability", "D": "Spinal canal stenosis", "E": "Hearing loss"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 56-year-old man presents to his primary care provider because of a lack of flexibility in his right hand. He has noticed that his hand has become less flexible and more fixed over the past year and he now has trouble shaking other people’s hands comfortably. He has a history of chronic alcohol abuse, hepatitis C, and cirrhosis. His family history is insignificant. He has a 40 pack-year smoking history. At the physician’s office, his blood pressure is 118/67 mm Hg, the respirations are 18/min, the pulse is 77/min, and the temperature is 36.7°C (98.0°F). On physical examination, the 4th and 5th digits are mildly flexed with dense, rope-like cords extending down his palm. Additionally, small ulcerations are identified on his palm. Which of the following is considered the first-line therapy for this condition?", "answer": "Collagenase injections", "options": {"A": "Surgery", "B": "Colchicine", "C": "Anti-TNF drugs", "D": "Steroid injections", "E": "Collagenase injections"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 35-year-old man presents to the physician with concerns that a “bad flu” he has had for the past 10 days is getting worse and causing sleeplessness. On presentation today, his sore throat has improved; however, fever and chest and body aches persist despite the use of ibuprofen. He reports sharp, intermittent chest pain that worsens with exertion. He has not traveled outside the United States recently and does not have a history of substance abuse or alcohol use. Physical examination shows the temperature is 38.3°C (100.9°F), the heart rate is 110/min, the blood pressure is 120/60 mm Hg, and the oxygen saturation is 98% on room air. There is bilateral pedal edema at the level of the ankle. Auscultation reveals normal S1 and S2 and a third early diastolic heart sound. Jugular vein distention is observed. An ECG shows sinus tachycardia and diffuse ST-segment elevation throughout the precordial leads with 1.0-mm PR-segment depression in leads I and II.\nLaboratory results\nWBC 14,000/mm3\nLymphocyte count 70%\nHematocrit 45%\nCRP 56 mg/dL\nTroponin T 1.15 ng/mL\nTroponin I 0.2 ng/mL\nCk-MB 22 ng/mL\nCoxsackie type b viral antibody  positive\nA chest x-ray shows clear lung fields bilaterally and a mildly enlarged cardiac silhouette. Transthoracic ultrasound reveals a left ventricular ejection fraction of 30%. Which of the following is the cause of difficulty sleeping for this patient?", "answer": "Decreased cardiac contractility due to cardiac myocyte injury", "options": {"A": "Progressive cardiac ischemia caused by a plaque event", "B": "Impaired gaseous exchange caused by pulmonary edema", "C": "Lobar consolidation due to Staphylococcus aureus", "D": "Decreased cardiac contractility due to cardiac myocyte injury", "E": "Diffuse alveolar damage and hyaline membrane formation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old man presents to the emergency department with shortness of breath, cough, and fever. He states that his symptoms started a few days ago and have been progressively worsening. The patient recently returned from international travel. He works from home and manages a chicken coop as a hobby. He has a past medical history of an ST-elevation myocardial infarction and recently has had multiple sick contacts. His temperature is 102°F (38.9°C), blood pressure is 187/108 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 93% on room air. A radiograph of the chest reveals bilateral pleural effusions. Pleurocentesis demonstrates the findings below:\n\nProtein ratio (pleural/serum): 0.8\nLactate dehydrogenase ratio (pleural/serum): 0.75\nGlucose: 25 mg/dL\n\nFurther analysis reveals a lymphocytic leukocytosis of the pleural fluid. Which of the following is the next best step in management?", "answer": "Rifampin, isoniazid, pyrazinamide, and ethambutol", "options": {"A": "Azithromycin and ceftriaxone", "B": "Azithromycin and vancomycin", "C": "Furosemide", "D": "Rifampin, isoniazid, pyrazinamide, and ethambutol", "E": "Supportive therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old sexually active male presents to an internal medicine physician for a routine health check up after having several unprotected sexual encounters. After appropriate testing the physician discusses with the patient that he is HIV+ and must be started on anti-retroviral treatment. Which of the following medications prescribed acts on the gp41 subunit of the HIV envelope glycoprotein?", "answer": "Enfuvirtide", "options": {"A": "Amantadine", "B": "Rimantadine", "C": "Zidovudine", "D": "Saquinavir", "E": "Enfuvirtide"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old primigravid woman who recently immigrated to the United States presents to her gynecologist for the first time during the 28th week of her pregnancy. She hasn’t received any prenatal care or folic acid supplementation. The patient’s history reveals that she has received blood transfusions in the past due to “severe anemia.” Which of the following blood type situations would put the fetus at risk for hemolytic disease of the newborn?", "answer": "Mother is A negative, father is B positive", "options": {"A": "Mother is B positive, father is O negative", "B": "Mother is O positive, father is B negative", "C": "Mother is A negative, father is B positive", "D": "Mother is AB negative, father is O negative", "E": "Mother is O positive, father is AB negative"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old male engineer who complains of shortness of breath when walking a few blocks undergoes a cardiac stress test because of concern for coronary artery disease. During the test he asks his cardiologist about what variables are usually used to quantify the functioning of the heart. He learns that one of these variables is stroke volume. Which of the following scenarios would be most likely to lead to a decrease in stroke volume?", "answer": "Heart failure", "options": {"A": "Anxiety", "B": "Exercise", "C": "Pregnancy", "D": "Heart failure", "E": "Digitalis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old woman presents to the clinic with an abnormal sensation on the left side of her body that has been present for the past several months. At first, the area seemed numb and she recalls touching a hot stove and accidentally burning herself but not feeling the heat. Now she is suffering from a constant, uncomfortable burning pain on her left side for the past week. The pain gets worse when someone even lightly touches that side. She has recently immigrated and her past medical records are unavailable. Last month she had a stroke but she cannot recall any details from the event. She confirms a history of hypertension, type II diabetes mellitus, and bilateral knee pain. She also had cardiac surgery 20 years ago. She denies fever, mood changes, weight changes, and trauma to the head, neck, or limbs. Her blood pressure is 162/90 mm Hg, the heart rate is 82/min, and the respiratory rate is 15/min. Multiple old burn marks are visible on the left hand and forearm. Muscle strength is mildly reduced in the left upper and lower limbs. Hyperesthesia is noted in the left upper and lower limbs. Laboratory results are significant for:\nHemoglobin 13.9 g/dL\nMCV 92 fL\nWhite blood cells 7,500/mm3\nPlatelets 278,000/mm3\nCreatinine 1.3 U/L\nBUN 38 mg/dL\nTSH 2.5 uU/L\nHemoglobin A1c 7.9%\nVitamin B12 526 ng/L\nWhat is the most likely diagnosis?", "answer": "Dejerine-Roussy syndrome", "options": {"A": "Complex regional pain syndrome", "B": "Conversion disorder", "C": "Dejerine-Roussy syndrome", "D": "Medial medullary syndrome", "E": "Subacute combined degeneration of spinal cord"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A young researcher is responsible for graphing laboratory data involving pulmonary blood flow and ventilation pattern obtained from a healthy volunteer who was standing in an upright position. After plotting the following graph, the researcher realizes he forgot to label the curves and the x-axis (which represents the position in the lung). Which of the following is the appropriate label for each point on the graph?", "answer": "A: Ventilation B: Blood flow C: Base of the lung D: Apex of the lung", "options": {"A": "A: Blood flow B: Ventilation C: Base of the lung D: Apex of the lung", "B": "A: Ventilation B: Blood flow C: Base of the lung D: Apex of the lung", "C": "A: Blood flow B: Ventilation C: Apex of the lung D: Base of the lung", "D": "A: Ventilation B: Blood flow C: Apex of the lung D: Base of the lung", "E": "A: Ventilation B: Blood flow C: Mid-portion of the lung D: Apex of the lung"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man is brought to the emergency department by his wife because of lethargy, confusion, and nausea for the past 2 days. He has previously been healthy and has no past medical history. His only medications are a daily multivitamin and acetaminophen, which he takes daily for hip pain. Vital signs are within normal limits. He is disoriented to place and time but recognizes his wife. The remainder of his physical examination shows no abnormalities. Laboratory studies show a hemoglobin concentration of 9.1 g/dL, a serum calcium concentration of 14.7 mg/dL, and a serum creatinine of 2.2 mg/dL (previously 0.9 mg/dL). Which of the following is the most likely underlying mechanism of this patient's condition?", "answer": "Overproliferation of plasma cells\n\"", "options": {"A": "Excessive consumption of calcium", "B": "Ectopic PTHrP release", "C": "Increased serum levels of 1,25-hydroxyvitamin D", "D": "Excess PTH secretion from parathyroid glands", "E": "Overproliferation of plasma cells\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-day-old female infant presents with poor feeding, lethargy, vomiting after feeding, and seizures. Labs revealed ketoacidosis and elevated hydroxypropionic acid levels. Upon administration of parenteral glucose and protein devoid of valine, leucine, methionine, and threonine, and carnitine, the infant began to recover. Which of the following enzymes is most likely deficient in this infant?", "answer": "Propionyl-CoA carboxylase", "options": {"A": "Branched-chain ketoacid dehydrogenase", "B": "Phenylalanine hydroxylase", "C": "Propionyl-CoA carboxylase", "D": "Cystathionine synthase", "E": "Homogentisate oxidase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 34-year-old woman presents with recurrent panic attacks that have been worsening over the past 5 weeks. She also says she has been seeing things that are not present in reality and is significantly bothered by a short attention span which has badly affected her job in the past 6 months. No significant past medical history. No current medications. The patient is afebrile and vital signs are within normal limits. Her BMI is 34 kg/m2. Physical examination is unremarkable. The patient has prescribed antipsychotic medication. She expresses concerns about any effects of the new medication on her weight. Which of the following medications would be the best course of treatment in this patient?", "answer": "Ziprasidone", "options": {"A": "Ziprasidone", "B": "Olanzapine", "C": "Clozapine", "D": "Clonazepam", "E": "Chlorpromazine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An investigator is studying the relationship between fetal blood oxygen saturation and intrauterine growth restriction using MRI studies. The magnetic resonance transverse relaxation time (T2) is inversely related to the concentration of deoxyhemoglobin so that high concentrations of deoxyhemoglobin produce a low signal intensity on T2-weighted MRI. In a normal fetus, the T2 signal is most likely to be the highest in which of the following vessels?", "answer": "Ductus venosus", "options": {"A": "Pulmonary veins", "B": "Ductus venosus", "C": "Superior vena cava", "D": "Descending aorta", "E": "Right atrium\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 29-year-old woman presents to her primary care physician because she has been experiencing episodes of intense fear. Specifically, she says that roughly once per week she will feel an intense fear of dying accompanied by chest pain, lightheadedness, sweating, and palpitations. In addition, she will feel as if she is choking which leads her to hyperventilate. She cannot recall any trigger for these episodes and is afraid that they will occur while she is driving or working. In order to avoid this possibility, she has been getting rides from a friend and has been avoiding interactions with her coworkers. These changes have not stopped the episodes so she came in for evaluation. This patient's disorder is most likely genetically associated with a personality disorder with which of the following features?", "answer": "Submissive, clingy, and low self-confidence", "options": {"A": "Criminality and disregard for rights of others", "B": "Eccentric appearance and magical thinking", "C": "Grandiosity, entitlement, and need for admiration", "D": "Social withdrawal and limited emotional expression", "E": "Submissive, clingy, and low self-confidence"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old man who was involved in a traffic collision is brought to the emergency room by the ambulance service. He was in shock and comatose at the time of presentation. On examination, the heart rate is 60/min, and the blood pressure is 70/40 mm Hg. The patient dies, despite resuscitative efforts. Autopsy reveals multiple internal hemorrhages and other evidence of ischemic damage affecting the lungs, kidneys, and brain. The patient’s heart shows evidence of gross anomaly similar to the picture. While acute hypovolemia is the likely cause of the ischemic changes seen in the lungs, kidneys, and brain, which of the following best explains the gross anomaly of his heart?", "answer": "Senile calcific aortic stenosis", "options": {"A": "Aortic valve regurgitation", "B": "Mitral valve stenosis", "C": "Senile calcific aortic stenosis", "D": "Accumulation of amyloid in the myocardium", "E": "Genetic mutation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 75-year-old woman with metastatic colon cancer comes to the physician requesting assistance in ending her life. She states: “I just can't take it anymore; the pain is unbearable. Please help me die.” Current medications include 10 mg oral hydrocodone every 12 hours. Her cancer has progressed despite chemotherapy and she is very frail. She lives alone and has no close family. Which of the following is the most appropriate initial action by the physician?", "answer": "Increase her pain medication dose", "options": {"A": "Submit a referral to psychiatry", "B": "Submit a referral to hospice care", "C": "Consult with the local ethics committee", "D": "Increase her pain medication dose", "E": "Initiate authorization of physician-assisted suicide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old man presents with a swollen left big toe that started this morning. The patient states that he attended a party last night and drank 4 glasses of whiskey. He denies any trauma to the foot. The patient has a history of similar episodes in the past that were related to alcohol use. His symptoms were previously relieved with ibuprofen. However, the pain persisted despite treatment with the medication. Physical examination reveals a tender and erythematous, swollen left 1st metatarsophalangeal joint. Which of the following events most likely contributed to his condition?", "answer": "Upregulation of cellular adhesion molecules to promote neutrophil migration", "options": {"A": "Vasoconstriction", "B": "Downregulation of integrins in the neutrophils", "C": "Upregulation of cellular adhesion molecules to promote neutrophil migration", "D": "Decreased expression of selectin in the endothelium", "E": "Activation of cytosolic caspases"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old woman presents to a pre-operative evaluation clinic prior to an elective cholecystectomy. She has a 5 pack-year smoking history. The anesthesiologist highly recommends to discontinue smoking for at least 8 weeks prior to the procedure for which she is compliant. What is the most likely histology of her upper respiratory tract's epithelial lining at the time of her surgery?", "answer": "Pseudostratified columnar", "options": {"A": "Simple squamous", "B": "Stratified squamous", "C": "Stratified columnar", "D": "Pseudostratified columnar", "E": "Simple columnar"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old man is brought to the emergency department by his wife for a 1-hour history of sudden behavior changes. They were having lunch together when, at 1:07 PM, he suddenly dropped his sandwich on the floor. Since then, he has been unable to use his right arm. She also reports that he is slurring his speech and dragging his right foot when he walks. Nothing like this has ever happened before. The vital signs include: pulse 95/min, blood pressure 160/90 mm Hg, and respiratory rate 14/min. The physical exam is notable for an irregularly irregular rhythm on cardiac auscultation. On neurological exam, he has a facial droop on the right half of his face but is able to elevate his eyebrows symmetrically. He has 0/5 strength in his right arm, 2/5 strength in his right leg, and reports numbness throughout the right side of his body. Angiography of the brain will most likely show a lesion in which of the following vessels?", "answer": "Middle cerebral artery", "options": {"A": "Internal carotid artery", "B": "Anterior cerebral artery", "C": "Middle cerebral artery", "D": "Posterior cerebral artery", "E": "Basilar artery"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old woman comes to the physician because of a 6-month history of worsening involuntary movement of the left hand. Her symptoms are worse when she feels stressed at work. She has no history of serious illness and takes no medications. Neurological examination shows difficulty initiating movement and a tremor in the left hand at rest. The tremor decreases when the patient is asked to draw a circle. Which of the following is the most appropriate pharmacotherapy?", "answer": "Pramipexole", "options": {"A": "Clonazepam", "B": "Methimazole", "C": "Trihexyphenidyl", "D": "Donepezil", "E": "Pramipexole"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 46-year-old man presents to the clinic complaining of fatigue and difficulty breathing for the past month. He reports that it is particularly worse when he exercises as he becomes out of breath at 1 mile when he used to routinely run 3 miles. He is frustrated as he was recently diagnosed with diabetes despite a good diet and regular exercise. He denies any weight changes, chest pain, or gastrointestinal symptoms. When asked about other concerns, his wife complains that he is getting darker despite regular sunscreen application. A physical examination demonstrates a tanned man with an extra heart sound just before S1, mild bilateral pitting edema, and mild bibasilar rales bilaterally. An echocardiogram is ordered and shows a left ventricular ejection fraction (LVEF) of 65% with reduced filling. What is the most likely explanation for this patient’s condition?", "answer": "Increased intestinal absorption of iron", "options": {"A": "Decreased copper excretion into bile", "B": "Increased intestinal absorption of iron", "C": "Infection with coxsackie B virus", "D": "Persistently elevated blood pressure", "E": "Systemic inflammatory state caused by type 2 diabetes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old soldier is rescued from a helicopter crash in the Arctic Circle and brought back to a treatment facility at a nearby military base. On arrival, the soldier’s wet clothes are removed. He appears pale and is not shivering. The patient is unresponsive to verbal or painful stimuli. His temperature is 27.4°C (81.3°F), the pulse is 30/min and irregular, the respiratory rate is 7/min, and the blood pressure is 83/52 mm Hg. Examination shows fixed, dilated pupils, and diffuse rigidity. The fingers and toes are white in color and hard to touch. An ECG shows atrial fibrillation. In addition to emergent intubation, which of the following is the most appropriate next step in patient management?", "answer": "Intravenous administration of warmed normal saline", "options": {"A": "Application of heating pads to the extremities", "B": "Emergent electrical cardioversion", "C": "Increasing the room temperature", "D": "Intravenous administration of tissue plasminogen activator", "E": "Intravenous administration of warmed normal saline"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old woman presents to the emergency department with abdominal pain that started while she was at the gym. The patient competes as a power lifter and states that her pain started after one of her heavier lifts. The patient has no significant past medical history and is currently taking a multivitamin and oral contraceptive pills. She smokes cigarettes and drinks alcohol regularly and is currently sexually active with multiple partners. Her temperature is 99°F (37.2°C), blood pressure is 85/55 mmHg, pulse is 125/min, respirations are 18/min, and oxygen saturation is 99% on room air. Physical exam is notable for right upper quadrant abdominal tenderness, acne, and muscle hypertrophy. Right upper quadrant ultrasound demonstrates a solitary heterogeneous mass. Which of the following other findings is most likely to be found in this patient?", "answer": "Increased LDL and decreased HDL", "options": {"A": "Elevated alpha fetoprotein", "B": "Elevated viral core antigen", "C": "Increased pigmentation in flexural areas", "D": "Increased LDL and decreased HDL", "E": "Prolonged PT and PTT"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A male newborn is delivered at term to a 26-year-old woman, gravida 2, para 3. The mother has no medical insurance and did not receive prenatal care. Physical examination shows microcephaly and ocular hypotelorism. There is a single nostril, cleft lip, and a solitary central maxillary incisor. An MRI of the head shows a single large ventricle and fused thalami. This patient's condition is most likely caused by abnormal expression of which of the following protein families?", "answer": "Hedgehog", "options": {"A": "Hedgehog", "B": "Transforming growth factor", "C": "Homeobox", "D": "Fibroblast growth factor", "E": "Wnt"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old woman presents to the emergency department for evaluation of a spreading skin infection that began from an ulcer on her foot. The patient has type 2 diabetes mellitus that is poorly controlled. On examination, there is redness and erythema to the lower limb with skin breakdown along an extensive portion of the leg. The patient’s tissues separate readily from the fascial plane, prompting a diagnosis of necrotizing fasciitis. What is the exotoxin most likely associated with this patient’s presentation?", "answer": "Streptococcal pyogenic exotoxin B", "options": {"A": "Diphtheria toxin", "B": "Streptococcal pyogenic exotoxin A", "C": "Exfoliative toxin", "D": "Streptococcal pyogenic exotoxin B", "E": "TSST-1"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man presents an urgent care clinic because he coughed up blood this morning. Although he had a persistent cough for the past 3 weeks, he had never coughed up blood until now. His voice is hoarse and admits that it has been like that for the past few months. Both his past medical history and family history are insignificant. He has smoked a pack of cigarettes a day since the age of 20 and drinks wine every night before bed. His vitals are: heart rate of 78/min, respiratory rate of 14/min, temperature of 36.5°C (97.8°F), blood pressure of 140/88 mm Hg. An indirect laryngoscopy reveals a rough vegetating lesion on the free border of the right vocal cord. Which of the following is the most likely diagnosis?", "answer": "Laryngeal carcinoma", "options": {"A": "Acute laryngitis", "B": "Leukoplakia", "C": "Polypoid corditis", "D": "Vocal cord nodule", "E": "Laryngeal carcinoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old male is brought into the emergency department by his girlfriend following an argument. The patient’s girlfriend claims that she threatened to break up with him. He then called her saying he was going to kill himself. When she arrived at the patient’s home, she found him lying on the couch with empty alcohol bottles and multiple pill containers. The patient reports he does not remember everything he took, but says he ingested many pills about four hours ago. The patient’s temperature is 99°F (37.2°C), blood pressure is 110/68 mmHg, pulse is 88/min, and respirations are 25/min with an oxygen saturation of 98% O2 on room air. An arterial blood gas (ABG) is obtained, with results shown below:\n\npH: 7.47\npO2: 94 mmHg\npCO2: 24 mmHg\nHCO3-: 22 mEq/L\n\nYou check on him a couple hours later, and the patient appears agitated. His girlfriend says he keeps grabbing his head, yelling about non-stop ringing in his ears. Labs and a repeat ABG shows:\n\npH: 7.30\npO2: 90 mmHg\npCO2: 22 mmHg\nHCO3-: 9 mEq/L\nNa+: 144 mEq/L\nCl-: 98 mEq/L\nK+: 3.6 mEq/L\nBUN: 18 mg/dL\nGlucose: 100 mg/dL\nCreatinine: 1.4 mg/dL\n\nWhich of the following is the best next step in management?", "answer": "IV sodium bicarbonate", "options": {"A": "Acetazolamide", "B": "Activated charcoal", "C": "N-acetylcysteine", "D": "IV haloperidol", "E": "IV sodium bicarbonate"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 82-year-old woman is brought to the physician by her nephew, who lives with her because she has a pessimistic attitude and has displayed overall distrust of her nephew for 1 year. She frequently argues with her nephew and embarrasses him in front of his friends. She had a Colles’ fracture 2 months ago and has had hypertension for 18 years. Her medications include hydrochlorothiazide and nortriptyline. She has a quantity of each leftover since her previous visit 2 months ago and has not requested new prescriptions, which she would need if she were taking them as prescribed. She appears untidy. Her blood pressure is 155/98 mm Hg. She mumbles in response to questions, and her nephew insists on being at her side during the entire visit because she cannot express herself clearly. She has a sore on her ischial tuberosity and bruises around her ankles. Which of the following is the most appropriate action in patient care?", "answer": "Reporting possible elder abuse by phone", "options": {"A": "Discussing advance directives", "B": "Emphasizing compliance with medication and follow-up in 1 month", "C": "Referral for hospice care", "D": "Referral to a psychiatrist", "E": "Reporting possible elder abuse by phone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 63-year-old man comes to the physician because of a 3-month history of fatigue and constipation. He reports having dull pain in the left portion of the midback for 2 weeks that has persisted despite taking ibuprofen. His father died of prostate cancer at 70 years of age. The patient has smoked one pack of cigarettes daily for 45 years. Vital signs are within normal limits. Physical examination shows a left-sided varicocele both in supine and in standing position. Rectal examination shows a symmetrically enlarged prostate with no masses. Laboratory studies show:\nHemoglobin 11.2 g/dL\nSerum\nCreatinine 1.0 mg/dL\nCalcium 11.8 mg/dL\nUrine\nProtein 1+\nBlood 2+\nWhich of the following is the most appropriate next step in management?\"", "answer": "CT scan of the abdomen", "options": {"A": "CT scan of the abdomen", "B": "Urine cytology", "C": "Chest x-ray", "D": "Prostate biopsy", "E": "Serum protein electrophoresis\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old woman with Ehlers-Danlos syndrome is brought to the emergency department with right knee pain and swelling after she twisted it while dancing. She had two similar episodes last year that were treated conservatively. She was treated for a fracture of her humerus 2 years ago. She has gastroesophageal reflux disease. Her sister has allergic rhinitis. Her only medication is omeprazole. She appears tense and uncomfortable. Her temperature is 37.1°C (99.3°F), pulse is 97/min, and blood pressure is 110/70 mm Hg. Examination shows mild scoliosis. The lungs are clear to auscultation. Cardiac examination shows a mid-systolic click. The right knee shows a large, tender effusion and the patella is displaced laterally. Lachman's test, the posterior drawer test, and Apley's test are negative. A complete blood count and serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. Toxicology screening is negative. X-ray of the knee joint shows an osteochondral fragment within the knee joint. What is the most appropriate next step in management?", "answer": "Arthroscopy", "options": {"A": "Arthroscopy", "B": "Above knee cast", "C": "Closed reduction", "D": "Total knee replacement", "E": "Physiotherapy only"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 64-year-old woman presents for the scheduled annual physical examination for management of her hypertension. The patient is asymptomatic and her blood pressure is within normal limits throughout the year. She has a past medical history of polyarthrosis, and she is a carrier of hepatitis B antibodies. She does not smoke or drink alcohol. She is currently taking the following medications: enalapril, ranitidine, and lorazepam. The vital signs include: pulse rate 72/min, respiratory rate 14/min, blood pressure 138/76 mm Hg, and temperature 37.0°C (98.6°F). The physical examination shows no abnormalities. The laboratory test results are shown below:\nHemoglobin 11.6 g/dL\nHematocrit 34.8%\nMCV 91.4 fL\nMCH 31.4 pg\nPlatelets 388,000/mm3\nLeukocytes 7,300/mm3\nESR 59 mm/h\nOn account of these laboratory test results, the patient was once again questioned for symptoms that would explain the abnormality detected in her laboratory test results. The patient insists that she is asymptomatic. Therefore, further laboratory studies were requested. The additional laboratory test results are shown below:\nPCR 5.3 mg/dL\nSerum protein electrophoresis\nTotal proteins 7.4 g/dL\nAlbumin 5.8 g/dL\nAlpha-1 3.5 g/dL\nAlpha-2 1 g/dL\nBeta 0.9 g/dL\nGamma 1.7 g/dL\nThe gamma protein was later confirmed as an immunoglobulin G (IgG) kappa paraprotein (1,040 mg/dL). Due to these results a computed tomography (CT) scan was conducted, and it showed moderate osteopathy without any other lesions. A bone marrow biopsy was done that showed 5–10% plasma cells. Which of the following is most likely associated with the diagnosis of this patient?", "answer": "Osteoporosis", "options": {"A": "Acanthosis nigricans", "B": "Myeloblasts with azurophilic granules", "C": "Osteoporosis", "D": "Richter’s transformation", "E": "Teardrop cells in blood smear"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl is brought to the physician for a physical examination prior to participating in sports. She has no history of serious illness. She is on the school's cheerleading team and is preparing for an upcoming competition. Menarche was at 13 years of age, and her last menstrual period was 4 months ago. She is 167 cm (5 ft 6 in) tall and weighs 45 kg (99 lb); BMI is 16.1 kg/m2. Examination shows pale skin with thin, soft body hair. The patient is at increased risk for which of the following complications?", "answer": "Fractures", "options": {"A": "Hyperkalemia", "B": "Hyperphosphatemia", "C": "Fractures", "D": "Shortened QT interval", "E": "Hyperthyroidism"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 63-year-old male is admitted to the Emergency Department after 3 days difficulty breathing, orthopnea, and shortness of breath with effort. His personal medical history is positive for a myocardial infarction 6 years ago and a cholecystectomy 10 years ago. Medications include metoprolol, lisinopril, atorvastatin, and as needed furosemide. At the hospital his  blood pressure is 108/60 mm Hg, pulse is 88/min, respiratory rate is 20/min, and temperature is 36.4°C (97.5°F). On physical examination, he presents with fine rales in both lungs, his abdomen is non-distended non-tender, and there is 2+ lower limb pitting edema up to his knees. Initial laboratory testing is shown below\nNa+ 138 mEq/L\nK+ 4 mEq/L\nCl- 102 mEq/L\nSerum creatinine (Cr) 1.8 mg/dL\nBlood urea nitrogen (BUN) 52 mg/dL\nWhich of the following therapies is the most appropriate for this patient?", "answer": "Furosemide", "options": {"A": "Furosemide", "B": "Normal saline", "C": "Hyperoncotic starch", "D": "Terlipressin", "E": "Norepinephrine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 42-year-old man presents to his primary care physician for a wellness checkup. The patient has a past medical history of obesity, constipation, and depression. His current medications include metformin, lactulose, and fluoxetine. His temperature is 99.5°F (37.5°C), blood pressure is 157/102 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Laboratory values are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 5,500/mm^3 with normal differential\nPlatelet count: 190,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 105 mEq/L\nK+: 3.5 mEq/L\nHCO3-: 21 mEq/L\nBUN: 20 mg/dL\nGlucose: 129 mg/dL\nCreatinine: 1.1 mg/dL\nAST: 12 U/L\nALT: 10 U/L\n\nUrine:\nAppearance: Yellow\nBacteria: Absent\nRed blood cells: 0/hpf\npH: 2.7\nNitrite: Absent\n\nWhich of the following is the next best step in management?", "answer": "Administer bicarbonate and repeat lab studies", "options": {"A": "Administer ammonium chloride and repeat lab studies", "B": "Administer bicarbonate and repeat lab studies", "C": "Administer high dose bicarbonate", "D": "Administer hydrochlorothiazide", "E": "Obtain urine sodium level"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old male presents to his physician with the complaint of fatigue and weakness for six months. His physician orders a CBC which demonstrates anemia and thrombocytopenia. During the subsequent work up, a bone marrow biopsy is performed which ultimately leads to the diagnosis of acute promyelocytic leukemia. Which of the following translocations and fusion genes would be present in this patient?", "answer": "t(15;17) - PML/RARalpha", "options": {"A": "t(8;14) - BCR/Abl1", "B": "t(9;22) - BCR/Abl1", "C": "t(15;17) - PML/RARalpha", "D": "t(14;18) - PML/RARalpha", "E": "t(9;22) - PML/RARalpha"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old man comes to the physician because of diarrhea, bloating, nausea, and vomiting for the past 3 days. He describes his stool as soft, frothy, and greasy. He denies seeing blood in stool. The patient went on a hiking trip last week and drank fresh water from the stream. Three months ago, he was on vacation with his family for 2 weeks in Brazil, where he tried many traditional dishes. He also had watery diarrhea and stomach cramping for 3 days during his visit there. He has no history of serious illness. He takes no medications. The patient appears dehydrated. His temperature is 37°C (98.6°F), blood pressure is 100/60 mm Hg, pulse is 80/min, and respirations are 12/min. Examination shows dry mucous membranes and diffuse abdominal tenderness. Microscopy of the stool reveals cysts. Which of the following is the most appropriate next step in management?", "answer": "Metronidazole therapy", "options": {"A": "Ciprofloxacin therapy", "B": "Octreotide therapy", "C": "Metronidazole therapy", "D": "Trimethoprim-sulfamethoxazole therapy", "E": "Supportive treatment only"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old man presents to his primary care physician with bilateral tremor of the hands. He is a senior in high school and during the year, his grades have plummeted to the point that he is failing. He says his memory is now poor, and he has trouble focusing on tasks. His behavior has changed in the past 6 months in that he has frequent episodes of depression, separated by episodes of bizarre behavior, including excessive alcohol drinking and shoplifting. His parents have started to suspect that he is using street drugs, which he denies. His handwriting has become very sloppy. His parents have noted slight slurring of his speech. Family history is irrelevant. Physical examination reveals upper extremity tremors, mild dystonia of the upper extremities, and mild incoordination involving his hands. The patient’s eye is shown. Which of the following is the best initial management of this patient’s condition?", "answer": "Oral zinc", "options": {"A": "Liver transplantation", "B": "Penicillamine", "C": "Oral zinc", "D": "Oral deferasirox", "E": "Watchful waiting"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old man comes to the physician because of a 2-week history of testicular swelling and dull lower abdominal discomfort. Physical examination shows a firm, nontender left testicular nodule. Ultrasonography of the scrotum shows a well-defined hypoechoic lesion of the left testicle. Serum studies show an elevated β-hCG concentration and a normal α-fetoprotein concentration. The patient undergoes a radical inguinal orchiectomy. Histopathologic examination of the surgical specimen shows a mixed germ cell tumor with invasion of adjacent lymphatic vessels. Further evaluation is most likely to show malignant cells in which of the following lymph node regions?", "answer": "Para-aortic", "options": {"A": "External iliac", "B": "Internal iliac", "C": "Mediastinal", "D": "Para-aortic", "E": "Deep inguinal"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old child is brought to a pediatric clinic with complaints of a foul-smelling, recurrent, persistent vaginal discharge that started a few days ago. The child shows increased irritability with a slightly elevated temperature. The mother says that the child plays in the house and has no contact with other children. What is the most common cause of this patient’s symptom?", "answer": "Foreign body in the vagina", "options": {"A": "Congenital rectovaginal fistula", "B": "Sarcoma botyroides", "C": "Foreign body in the vagina", "D": "Clear cell carcinoma of the cervix", "E": "Sexual abuse"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old man presents to his primary care physician complaining of pain accompanied by a feeling of heaviness in his scrotum. He is otherwise healthy except for a broken arm he obtained while skiing several years ago. Physical exam reveals an enlarged “bag of worms” upon palpation of the painful scrotal region. Shining a light over this area shows that the scrotum does not transilluminate. Which of the following statements is true about the most likely cause of this patient's symptoms?", "answer": "More common on left due to drainage into renal vein", "options": {"A": "Equally common on both sides", "B": "More common on left due to drainage into inferior vena cava", "C": "More common on left due to drainage into renal vein", "D": "More common on right due to drainage into inferior vena cava", "E": "More common on right due to drainage into renal vein"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old primigravid woman at 34-weeks' gestation comes to the physician because of an 8-day history of generalized pruritus. She has no history of rash. She has had standard prenatal care. Three weeks ago she was diagnosed with iron deficiency anemia. She traveled to Mexico for a vacation 3 months ago. She takes her multivitamin supplements inconsistently. Her blood pressure is 110/80 mm Hg. Examination shows pallor and mild scleral icterus. The uterus is soft, nontender, and consistent in size with a 34-week gestation. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11 g/dL\nLeukocyte count 8,000/mm3\nPlatelet 250,000/mm3\nProthrombin time 11 seconds\nSerum\nTotal bilirubin 4 mg/dL\nDirect bilirubin 3.2 mg/dL\nBile acid 15 μmol/L (N = 0.3–10)\nAST 45 U/L\nALT 50 U/L\nA peripheral blood smear is normal. There are no abnormalities on abdominopelvic ultrasonography. Which of the following is the most likely diagnosis?\"", "answer": "Cholestasis of pregnancy", "options": {"A": "Cholestasis of pregnancy", "B": "Viral hepatitis A", "C": "Gilbert syndrome", "D": "Acute fatty liver of pregnancy", "E": "HELLP syndrome"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old woman comes to the physician because of a 1-week history of white discoloration of the tongue. She has had similar, recurrent episodes over the past 5 years. Examination shows white plaques on the tongue that easily scrape off and thick, cracked fingernails with white discoloration. KOH preparation of a tongue scraping shows budding yeasts with pseudohyphae. This patient's condition is most likely caused by decreased activity of which of the following?", "answer": "T cells", "options": {"A": "B cells", "B": "Complement C5–9", "C": "T cells", "D": "Complement C1–4", "E": "Neutrophils"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old man returns to his physician for a follow-up examination. During his last visit 1 month ago splenomegaly was detected. He has had night sweats for the past several months and has lost 5 kg (11 lb) unintentionally during this period. He has no history of a serious illness and takes no medications. The vital signs are within normal limits. The physical examination shows no abnormalities other than splenomegaly. The laboratory studies show the following:\nHemoglobin 9 g/dL\nMean corpuscular volume 95 μm3\nLeukocyte count 12,000/mm3\nPlatelet count 260,000/mm3\nUltrasound shows a spleen size of 15 cm (5.9 in) and mild hepatomegaly. The peripheral blood smear shows teardrop-shaped and nucleated red blood cells (RBCs) and immature myeloid cells. The marrow is very difficult to aspirate but reveals hyperplasia of all 3 lineages. The tartrate-resistant acid phosphatase (TRAP) test is negative. Clonal marrow plasma cells are not seen. JAK-2 is positive. The cytogenetic analysis is negative for translocation between chromosomes 9 and 22. Which of the following is the most appropriate curative management in this patient?", "answer": "Allogeneic bone marrow transplantation", "options": {"A": "Adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD)", "B": "Allogeneic bone marrow transplantation", "C": "Imatinib mesylate", "D": "Splenectomy", "E": "Splenic irradiation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old previously healthy man comes to his physician because of dyspnea and hemoptysis for the past week. Examination shows inspiratory crackles at both lung bases. The remainder of the examination shows no abnormalities. His hemoglobin concentration is 14.2 g/dL, leukocyte count is 10,300/mm3, and platelet count is 205,000/mm3. Urine dipstick shows 2+ proteins. Urinalysis shows 80 RBC/hpf and 1–2 WBC/hpf. An x-ray of the chest shows pulmonary infiltrates. Further evaluation is most likely to show increased serum titers of which of the following?", "answer": "Anti-GBM antibody", "options": {"A": "Immunoglobulin A", "B": "Anti-GBM antibody", "C": "Anti-dsDNA antibody", "D": "Anti-PLA2R antibody", "E": "P-ANCA"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old man presents to the clinic for a second evaluation of worsening blackened ulcers on the tips of his toes. His past medical history includes diabetes mellitus for which he takes metformin and his most recent HgA1c was 6.0, done 3 months ago. He also has hypertension for which he’s prescribed amlodipine and chronic obstructive pulmonary disease (COPD) for which he uses an albuterol-ipratropium combination inhaler. He is also a chronic tobacco user with a 27-pack-year smoking history. He first noticed symptoms of a deep aching pain in his toes. Several months ago, he occasionally felt pain in his fingertips both at rest and with activity. Now he reports blackened skin at the tips of his fingers and toes. Evaluation shows: pulse of 82/min, blood pressure of 138/85 mm Hg, oral temperature 37.0°C (98.6°F). He is thin. Physical examination of his feet demonstrates the presence of 3, 0.5–0.8 cm, eschars over the tips of his bilateral second toes and right third toe. There is no surrounding erythema or exudate. Proprioception, vibratory sense, and monofilament examination are normal on both ventral aspects of his feet, but he lacks sensation over the eschars. Dorsal pedal pulses are diminished in both feet; the skin is shiny and hairless. Initial lab results include a C-reactive protein (CRP) level of 3.5 mg/dL, leukocytes of 6,000/mm3, erythrocyte sedimentation rate (ESR) of 34 mm/hr, and negative antinuclear antibodies. Which part of the patient's history is most directly associated with his current problem?", "answer": "Tobacco smoking", "options": {"A": "Diabetes mellitus", "B": "Tobacco smoking", "C": "Autoimmune disorder", "D": "Hypertension", "E": "Chronic obstructive pulmonary disease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old man is brought to the emergency department 10 minutes after he sustained a stab wound to the left chest just below the clavicle. On arrival, he is hypotensive with rapid and shallow breathing and appears anxious and agitated. He is intubated and mechanically ventilated. Infusion of 0.9% saline is begun. Five minutes later, his pulse is 137/min and blood pressure is 84/47 mm Hg. Examination shows a 3-cm single stab wound to the left chest at the 4th intercostal space at the midclavicular line without active external bleeding. Cardiovascular examination shows muffled heart sounds and jugular venous distention. Breath sounds are normal bilaterally. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "A 15 mm Hg decrease in systolic blood pressure during inspiration", "options": {"A": "A 15 mm Hg decrease in systolic blood pressure during inspiration", "B": "Cough productive of frank blood", "C": "Lateral shift of the trachea toward the right side", "D": "Subcutaneous crepitus on palpation of the chest wall", "E": "Inward collapse of part of the chest with inspiration"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old woman comes to the physician for a follow-up examination. At her visit 1 month ago, her glomerular filtration rate (GFR) was 100 mL/min/1.73 m2 and her renal plasma flow (RPF) was 588 mL/min. Today, her RPF is 540 mL/min and her filtration fraction (FF) is 0.2. After her previous appointment, this patient was most likely started on a drug that has which of the following effects?", "answer": "Constriction of the efferent arteriole", "options": {"A": "Relaxation of urinary smooth muscle", "B": "Inhibition of the renal Na-K-Cl cotransporter", "C": "Inhibition of vasopressin", "D": "Constriction of the afferent arteriole", "E": "Constriction of the efferent arteriole"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old man with coronary artery disease comes to the emergency department because of chest pain and shortness of breath for the past 3 hours. Troponin levels are elevated and an ECG shows ST-elevations in the precordial leads. Revascularization with percutaneous coronary intervention is performed, and a stent is successfully placed in the left anterior descending artery. Two days later, he complains of worsening shortness of breath. Pulse oximetry on 3L of nasal cannula shows an oxygen saturation of 89%. An x-ray of the chest shows distended pulmonary veins, small horizontal lines at the lung bases, and blunting of the costophrenic angles bilaterally. Which of the following findings would be most likely on a ventilation-perfusion scan of this patient?", "answer": "Normal perfusion with bilateral ventilation defects", "options": {"A": "Increased apical ventilation with normal perfusion bilaterally", "B": "Normal ventilation with multiple, bilateral perfusion defects", "C": "Matched ventilation and perfusion bilaterally", "D": "Normal perfusion with bilateral ventilation defects", "E": "Normal perfusion with decreased ventilation at the right base"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old woman presented to the hospital with a headache, intermittent fevers and chills, generalized arthralgias, excessive thirst, increased fluid intake, and a progressive rash that developed on her back. Three days before seeking evaluation at the hospital, she noticed a small, slightly raised lesion appearing like a spider or insect bite on her back, which she considered to be a scab covering the affected region. The patient's fever reached 39.4°C (102.9°F) 2 days before coming to the hospital, with an intensifying burning sensation on the affected site. When a family member examined the bite, it was noticed that the bump had transformed into a circular rash. The patient took over-the-counter ibuprofen for intense pain so she could sleep through the night. The day before her hospital visit, the patient felt exhausted but managed to complete a normal workday. On the day of the hospital visit, she awoke feeling very ill, with shooting joint pains, high fevers, and excessive thirst, which led to her to seek medical attention. On physical examination, her temperature was 40.1°C (104.2°F), and there was a large circular red rash with a bulls-eye appearance (17 × 19 cm in diameter) on her back. The rest of the physical examination was unremarkable. Her past medical and surgical histories were not significant apart from a history of anaphylaxis when taking a tetracycline. She recalled a walk in the woods 3 weeks before this exam but denied finding a tick or any other ectoparasite on her body. She denied any nutritional or inhalational allergies, although she emphasized that she is allergic to tetracyclines. Based on her symptoms, medical history, and physical examination findings, the attending physician decides to institute antimicrobial therapy immediately. Which antimicrobial drug did the physician prescribe?", "answer": "Amoxicillin", "options": {"A": "Cephalexin", "B": "Amoxicillin", "C": "Azithromycin", "D": "Erythromycin", "E": "Doxycycline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy is brought to the emergency department by his mother because of a cough and mild shortness of breath for the past 12 hours. He has not had fever. He has been to the emergency department 4 times during the past 6 months for treatment of asthma exacerbations. His 9-month-old sister was treated for bronchiolitis a week ago. His father has allergic rhinitis. Current medications include an albuterol inhaler and a formoterol-fluticasone inhaler. He appears in mild distress. His temperature is 37.5°C (99.5°F), pulse is 101/min, respirations are 28/min, and blood pressure is 86/60 mm Hg. Examination shows mild intercostal and subcostal retractions. Pulmonary examination shows decreased breath sounds and mild expiratory wheezing throughout the right lung field. Cardiac examination shows no abnormalities. An x-ray of the chest shows hyperlucency of the right lung field with decreased pulmonary markings. Which of the following is the next best step in management?", "answer": "Bronchoscopy", "options": {"A": "Bronchoscopy", "B": "Albuterol nebulization", "C": "Racemic epinephrine", "D": "CT of the lung", "E": "Azithromycin therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 37-year-old man presents to the emergency department after he cut his hand while working on his car. The patient has a past medical history of antisocial personality disorder and has been incarcerated multiple times. His vitals are within normal limits. Physical exam is notable for a man covered in tattoos with many bruises over his face and torso. Inspection of the patient's right hand reveals 2 deep lacerations on the dorsal aspects of the second and third metacarpophalangeal (MCP) joints. The patient is given a tetanus vaccination, and the wound is irrigated. Which of the following is appropriate management for this patient?", "answer": "Surgical irrigation, debridement, and amoxicillin-clavulanic acid", "options": {"A": "Ciprofloxacin and topical erythromycin", "B": "Clindamycin and topical erythromycin", "C": "Closure of the wound with sutures", "D": "No further management necessary", "E": "Surgical irrigation, debridement, and amoxicillin-clavulanic acid"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 39-year-old woman comes to the physician because of progressive pain and swelling of her wrists and hands for the past 2 months. Her hands are stiff in the morning; the stiffness decreases as she starts her chores. She also reports early-morning neck pain at rest for the past 3 weeks. She has no history of serious illness and takes no medications. Her sister has systemic lupus erythematosus. Vital signs are within normal limits. Examination shows bilateral swelling and tenderness of the wrists, second, third, and fourth metacarpophalangeal joints; range of motion is limited by pain. There is no vertebral tenderness. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. Laboratory studies show:\nHemoglobin 12.8 g/dL\nLeukocyte count 9,800/mm3\nErythrocyte sedimentation rate 44 mm/h\nSerum\nGlucose 77 mg/dL\nCreatinine 1.1 mg/dL\nTotal bilirubin 0.7 mg/dL\nAlkaline phosphatase 33 U/L\nAST 14 U/L\nALT 13 U/L\nRheumatoid factor positive\nWhich of the following is the most appropriate next step in management?\"", "answer": "X-ray of the cervical spine", "options": {"A": "Adalimumab", "B": "X-ray of the cervical spine", "C": "Measurement of anti-Smith antibodies", "D": "CT scan of the chest", "E": "Tuberculin skin test"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 54-year-old man comes to the physician because of a cough with blood-tinged sputum for 1 week. He also reports fever and a 5-kg (11 lb) weight loss during the past 2 months. Over the past year, he has had 4 episodes of sinusitis. Physical examination shows palpable nonblanching skin lesions over the hands and feet. Examination of the nasal cavity shows ulceration of the nasopharyngeal mucosa and a depressed nasal bridge. Oral examination shows a painful erythematous gingival enlargement that bleeds easily on contact. Which of the following is the most likely cause of the patient's symptoms?", "answer": "Neutrophil-mediated damage", "options": {"A": "Metalloprotease enzyme deficiency", "B": "Neutrophil-mediated damage", "C": "Arteriovenous malformation", "D": "Immune complex deposition", "E": "Malignant myeloid cell proliferation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old pregnant woman in the 28th week of gestation presents to the emergency department for evaluation of bilateral edema of her legs. It seems to worsen at the end of the day and has lasted for the past 3 weeks. History reveals that this is her 3rd pregnancy. Vital signs include: blood pressure 120/80 mm Hg, heart rate 74/min, respiratory rate 18/min, and temperature 36.6°C (98.0°F). Body mass index is 36 kg/m2. Physical examination reveals bilateral leg edema with engorged surface veins. A photograph of the patient’s legs is shown. Which of the following is the best initial management of the patient?", "answer": "Compression stockings", "options": {"A": "Compression stockings", "B": "Enoxaparin", "C": "Endovenous laser treatment", "D": "Foam sclerotherapy", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 9-year-old boy presents with abdominal pain that started nearly 6 hours ago. The pain is located in the periumbilical area and radiates to the right lower quadrant. There was no vomiting or passage of stool since the onset of pain. The patient reports that he passed stools with blood several times during the past month. The vital signs include: blood pressure 110/70 mm Hg, heart rate 81/min, respiratory rate 16/min, and temperature 37.5℃ (99.5℉). The physical examination reveals abdominal tenderness and guarding in the periumbilical area. An abdominal ultrasound does not reveal an appendiceal abnormality. The patient underwent an exploratory laparoscopy. At the time of laparoscopy, a 2-cm wide inflamed diverticulum is found 40 cm proximal to the ileocecal valve. The diverticulum is resected and sent for histologic evaluation. The result is shown in the exhibit. Which of the following statements is true?", "answer": "It is a remnant of the embryonic omphalomesenteric duct.", "options": {"A": "It resulted from traction by embryonic peritoneal adhesions.", "B": "The most probable cause of this diverticulum is increased intraluminal pressure.", "C": "It is an unobliterated embryonic bile duct.", "D": "It is a remnant of the embryonic omphalomesenteric duct.", "E": "It is a false diverticulum."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man comes to the physician for a routine health visit. He feels well except for occasional left-sided abdominal discomfort and left shoulder pain. He has smoked 1 pack of cigarettes daily for 20 years. He does not drink alcohol. His pulse is 85/min and his blood pressure is 130/70 mmHg. Examination shows a soft, nontender abdomen. The spleen is palpated 5 cm below the costal margin. There is no lymphadenopathy present. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12.2 g/dL\nHematocrit 36 %\nLeukocyte count 34,000/mm3\nPlatelet count 450,000/mm3\nCytogenetic testing of his blood cells is pending. Further evaluation of this patient is most likely to show which of the following findings?\"", "answer": "Low leukocyte alkaline phosphatase score", "options": {"A": "Low leukocyte alkaline phosphatase score", "B": "Elevated serum calcium", "C": "Decreased basophil count", "D": "Autoimmune hemolytic anemia", "E": "Elevated serum β2 microglobulin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old boy comes to the physician for a follow-up examination. Two months ago, he suffered a spinal fracture after a fall from the roof. He feels well. His father has multiple endocrine neoplasia type 1. Vital signs are within normal limits. Examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13.7 g/dL\nSerum\nCreatinine 0.7 mg/dL\nProteins\nTotal 7.0 g/dL\nAlbumin 4.1 g/dL\nCalcium 11.4 mg/dL\nPhosphorus 5.3 mg/dL\nAlkaline phosphatase 100 U/L\nWhich of the following is the most likely cause of these findings?\"", "answer": "Immobilization", "options": {"A": "Sarcoidosis", "B": "Immobilization", "C": "Parathyroid adenoma", "D": "Pseudohypercalcemia", "E": "Paraneoplastic syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old woman presents to the ED with nausea, vomiting, diarrhea, abdominal pain, and hematemesis after ingesting large quantities of a drug. Which of the following pairs a drug overdose with the correct antidote for this scenario?", "answer": "Iron; deferoxamine", "options": {"A": "Iron; deferoxamine", "B": "Aspirin; N-acetylcysteine", "C": "Atropine; fomepizole", "D": "Organophosphate; physostigmine", "E": "Acetaminophen; naloxone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old soldier is brought to the emergency department of a military hospital 20 minutes after being involved in a motor vehicle accident during a training exercise. He was an unrestrained passenger. On arrival, he has shortness of breath and chest pain. He appears pale and anxious. His temperature is 37°C (98.6°F), pulse is 110/min, respirations are 20/min, and blood pressure is 100/65 mm Hg. He is alert and oriented to person, place, and time. Examination shows pale conjunctivae and mucous membranes. There is bruising on the chest, extremities, and abdomen. The lungs are clear to auscultation. He has normal heart sounds and flat neck veins. The abdomen is flat, soft, and mildly tender. The remainder of the physical examination shows no abnormalities. High-flow oxygen is applied, and intravenous fluid resuscitation is begun. An x-ray of the chest is shown. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the chest with contrast", "options": {"A": "Pericardiocentesis", "B": "CT scan of the chest with contrast", "C": "Abdominal ultrasonography", "D": "Placement of a chest tube", "E": "Intubation with positive pressure ventilation\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying the effects of influenza virus on human lung tissue. Biopsy specimens of lung parenchyma are obtained from patients recovering from influenza pneumonia and healthy control subjects. Compared to the lung tissue from the healthy control subjects, the lung tissue from the affected patients is most likely to show which of the following findings on histopathologic examination?", "answer": "Increased type II pneumocytes", "options": {"A": "Decreased alveolar macrophages", "B": "Decreased interstitial fibroblasts", "C": "Increased type II pneumocytes", "D": "Increased alveolar squamous epithelial cells", "E": "Increased goblet cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old male with cystic fibrosis is brought to the emergency room by his mother after he had difficulty breathing. He previously received a lung transplant 6 months ago and was able to recover quickly from the operation. He is compliant with all of his medications and had been doing well with no major complaints until 2 weeks ago when he began to experience shortness of breath. Exam reveals a decreased FEV1/FVC ratio and biopsy reveals lymphocytic infiltration. Which of the following components is present in the airway zone characteristically affected by the most likely cause of this patient's symptoms?", "answer": "Simple cuboidal cells", "options": {"A": "Cartilage", "B": "Goblet cells", "C": "Pseudostratified columnar cells", "D": "Simple cuboidal cells", "E": "Stratified cuboidal cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old G1P0 presents to the emergency department with severe abdominal pain. She states that the pain has been recurring every 3 to 5 minutes for the past 5 hours. She denies having regular prenatal care but recalls that her last menstrual period was about 9 months ago. She denies taking or using any substances. Her temperature is 98°F (37°C), blood pressure is 120/60 mmHg, pulse is 120/min, and respirations are 8/min. Tenderness is elicited in the lower abdominal quadrants. Clear fluid is seen in her vaginal vault with a fetal crown seen at 10 cm cervical dilation and +1 station. The patient is emergently taken into the labor and delivery suite, where she delivers a male infant with APGAR scores of 9 and 9 at 5 and 10 minutes, respectively. Several hours after delivery, the nurse notes that the infant is very irritable and crying in high pitches. The infant appears very diaphoretic with a runny nose and flailing limbs. What is the necessary pharmacological treatment for this patient?", "answer": "Morphine", "options": {"A": "Acetaminophen", "B": "Diazepam", "C": "Naloxone", "D": "Phenobarbital", "E": "Morphine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old man with a history of myocardial infarction 3 months ago presents with feelings of depression. He says that he has become detached from his friends and family and has daily feelings of hopelessness. He says he has started to avoid strenuous activities and is no longer going to his favorite bar where he used to spend a lot of time drinking with his buddies. The patient says these symptoms have been ongoing for the past 6 weeks, and his wife is starting to worry about his behavior. He notes that he continues to have nightmares that he is having another heart attack. He says he is even more jumpy than he used to be, and he startles very easily. Which of the following is the most likely diagnosis in this patient?", "answer": "Post-traumatic stress disorder", "options": {"A": "Post-traumatic stress disorder", "B": "Acute stress disorder", "C": "Major depression disorder", "D": "Alcohol withdrawal", "E": "Midlife crisis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old man presents to the emergency department with complaints of severe malaise, fevers, and sore throat for the past 7 days. He also has had episodes of nausea and vomiting during this period. He does not smoke or drink alcohol. There is no family history of liver disease. His blood pressure is 130/80 mm Hg, temperature is 38.3℃ (100.9℉), pulse is 102/min, and respiratory rate is 20/min. On physical examination, he appears ill with bilateral cervical lymphadenopathy. His tonsils are erythematous and enlarged. There is no jaundice and he is mildly dehydrated. Abdominal examination demonstrates splenomegaly. The laboratory findings are shown below:\nHemoglobin  15 g/dL\nPlatelet count  95,000/mm³\nLeukocytes 13,500/mm³\nNeutrophils  50%\nAtypical lymphocytes  34%\nAST 232 U/L\nALT 312 U/L\nALP 120 U/L\nGGT 35 U/L\nTotal bilirubin 1.2 mg/dL\nDirect bilirubin 0.2 mg/dL\nPT 12 seconds\nThe serologic test for hepatitis A, B, and C, CMV, and leptospirosis are negative. Serology for both serum IgM and IgG antibodies for EBV capsid antigen are positive, but the heterophile antibody test is negative. What is the most likely reason for the negative heterophile test?", "answer": "False negative", "options": {"A": "Low specificity", "B": "Age of the patient", "C": "False negative", "D": "Concurrent viral hepatitis A infection", "E": "CMV infection"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old otherwise healthy male presents to his primary care physician for a check-up. He has no complaints. His blood pressure at the previous visit was 160/95. The patient did not wish to be on any medications and at the time attempted to manage his blood pressure with diet and exercise. On repeat measurement of blood pressure today, the reading is 163/92. His physician decides to prescribe a medication which the patient agrees to take. The patient calls his physician 6 days later complaining of a persistent cough, but otherwise states that his BP was measured as 145/85 at a local pharmacy. Which of the following is a contraindication to this medication?", "answer": "Bilateral renal artery stenosis", "options": {"A": "Chronic obstructive pulmonary disease", "B": "Gout", "C": "Bilateral renal artery stenosis", "D": "Congestive heart failure", "E": "Black race"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 61-year-old man comes to the physician because of progressively worsening swelling of his ankles. He says he has felt exhausted lately. Over the past 3 months, he has gained 5 kg. He has smoked one pack of cigarettes daily for 30 years. His pulse is 75/min and his blood pressure is 140/90 mmHg. Examination shows 2+ pitting edema in the lower extremities. Neurologic exam shows diminished two-point discrimination in the fingers and toes. A urine sample is noted to be foamy. Laboratory studies show a hemoglobin A1c of 7.9% and creatinine of 1.9 mg/dL. A biopsy specimen of the kidney is most likely to show which of the following?", "answer": "Nodular glomerulosclerosis", "options": {"A": "Interstitial inflammation", "B": "Wire looping of capillaries", "C": "Nodular glomerulosclerosis", "D": "Immune complex deposition", "E": "Split glomerular basement membrane"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 21-year-old man presents to the office for a follow-up visit. He was recently diagnosed with type 1 diabetes mellitus after being hospitalized for diabetic ketoacidosis following a respiratory infection. He is here today to discuss treatment options available for his condition. The doctor mentions a recent study in which researchers have developed a new version of the insulin pump that appears efficacious in type 1 diabetics. They are currently comparing it to insulin injection therapy. This new pump is not yet available, but it looks very promising. At what stage of clinical trials is this current treatment most likely at?", "answer": "Phase 3", "options": {"A": "Phase 1", "B": "Phase 4", "C": "Phase 3", "D": "Phase 0", "E": "Phase 2"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 64-year-old man presents to his physician for a scheduled follow-up visit. He has chronic left-sided heart failure with systolic dysfunction. His current regular medications include captopril and digoxin, which were started after his last episode of symptomatic heart failure approximately 3 months ago. His last episode of heart failure was accompanied by atrial fibrillation, which followed an alcohol binge over a weekend. Since then he stopped drinking. He reports that he has no current symptoms at rest and is able to perform regular physical exercise without limitation. On physical examination, mild bipedal edema is noted. The physician suggested to him that he should discontinue digoxin and continue captopril and scheduled him for the next follow-up visit. Which of the following statements best justifies the suggestion made by the physician?", "answer": "Captopril is likely to improve the long-term survival of the patient with heart failure, unlike digoxin.", "options": {"A": "Digoxin is useful to treat atrial fibrillation, but does not benefit patients with systolic dysfunction who are in sinus rhythm.", "B": "Digoxin does not benefit patients with left-sided heart failure in the absence of atrial fibrillation.", "C": "Captopril is likely to improve the long-term survival of the patient with heart failure, unlike digoxin.", "D": "Both captopril and digoxin are likely to improve the long-term survival of the patient with heart failure, but digoxin has more severe side effects.", "E": "Long-term digoxin therapy produces significant survival benefits in patients with heart failure, but at the cost of increased heart failure-related admissions."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 26-year-old male professional soccer player is brought to the emergency department due to an episode of syncope during a game. He has felt increasing shortness of breath during the past 3 months. During the past week, he has been feeling chest pain upon exertion. He also tells the doctor that his brother had a sudden death a couple of years ago. His heart rate is 98/min, respiratory rate is 18/min, temperature is 36.5°C (97.7°F), and blood pressure is 110/72 mm Hg. On physical examination, there is a harsh crescendo-decrescendo systolic murmur immediately after S1; it is best heard on the apex, and it radiates to the axilla. There is also an early diastolic murmur heard in early diastole, which is best heard with the bell of the stethoscope. When the Valsalva maneuver is performed, the murmur becomes louder. An ECG and an echocardiogram are performed, which confirm the diagnosis. What is the most likely cause of this patient’s condition?", "answer": "Hypertrophic cardiomyopathy", "options": {"A": "Aortic stenosis", "B": "Cardiac tamponade", "C": "First-degree heart block", "D": "Hypertrophic cardiomyopathy", "E": "Third-degree heart block"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 61-year-old man presents to the emergency department because he has developed blisters at multiple locations on his body. He says that the blisters appeared several days ago after a day of hiking in the mountains with his colleagues. When asked about potential triggering events, he says that he recently had an infection and was treated with antibiotics but he cannot recall the name of the drug that he took. In addition, he accidentally confused his medication with one of his wife's blood thinner pills several days before the blisters appeared. On examination, the blisters are flesh-colored, raised, and widespread on his skin but do not involve his mucosal surfaces. The blisters are tense to palpation and do not separate with rubbing. Pathology of the vesicles show that they continue under the level of the epidermis. Which of the following is the most likely cause of this patient's blistering?", "answer": "Antibodies to proteins connecting intermediate filaments to type IV collagen", "options": {"A": "Antibodies to proteins connecting intermediate filaments to type IV collagen", "B": "Antibodies to proteins connecting two sets of intermediate filaments", "C": "Depletion of protein C and protein S levels", "D": "Infection with a enveloped dsDNA virus", "E": "Necrosis of skin in reaction to a drug"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old woman presents to her gynecologist for a routine well-visit. She is sexually active with multiple male partners and uses an intrauterine device for contraception. Her last menstrual period was two weeks ago. She denies abnormal vaginal discharge or sensations of burning or itching. Pelvic exam is normal. Routine Pap smear shows the following (see Image A). Which organism is most likely responsible for her abnormal Pap smear?", "answer": "Human papillomavirus", "options": {"A": "Treponema pallidum", "B": "Chlamydia trachomatis", "C": "Herpes simplex virus 1", "D": "Human papillomavirus", "E": "Trichomonas vaginalis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman presents to the emergency room with a rash over her shins for the last 3 months. She also has a swell in her knee and wrist joints on both sides for a few days. The rash is painful and erythematous. She had an episode of uveitis 6 months ago that was treated with topical therapy. She is not on any medication currently. In addition, she stated that 3 weeks ago she went hiking with her family and found a tick attached to her left thigh. Her vital signs include a blood pressure of 135/85 mm Hg, a pulse of 85/min, and a respiratory rate of 12/min. Physical examination shows swelling of the ankles, knees, and wrists bilaterally, and well-demarcated papules over the anterior aspect of both legs. A chest X-ray is performed and demonstrates bilateral hilar lymphadenopathy. Which of the following is the pathophysiologic mechanism behind this patient’s condition?", "answer": "Activation of T lymphocytes", "options": {"A": "Loss of protection against proteases", "B": "Formation of caseating granulomas", "C": "Release of toxins by spirochete", "D": "Activation of T lymphocytes", "E": "Activation of Langerhans cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old woman comes to the physician because of a 2-month history of increased urination. She has also had dry mouth and excessive thirst despite drinking several gallons of water daily. She has a history of obsessive-compulsive disorder treated with citalopram. She drinks 1–2 cans of beer daily. Physical examination shows no abnormalities. Serum studies show a Na+ concentration of 130 mEq/L, a glucose concentration of 185 mg/dL, and an osmolality of 265 mOsmol/kg. Urine osmolality is 230 mOsmol/kg. The patient is asked to stop drinking water for 3 hours. Following water restriction, repeated laboratory studies show a serum osmolality of 280 mOsmol/kg and a urine osmolality of 650 mOsmol/kg. Which of the following is the most likely diagnosis?", "answer": "Primary polydipsia", "options": {"A": "Primary hyperparathyroidism", "B": "Syndrome of inappropriate ADH secretion", "C": "Nephrogenic diabetes insipidus", "D": "Primary polydipsia", "E": "Beer potomania"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old man presents with unilateral severe chest pain which started a day ago. He describes the chest pain as sharp in nature and localized mainly to his right side. He also complains of mild shortness of breath but says that it is tolerable. He denies any recent history of fever, sweating, dizziness, or similar episodes in the past. Past medical history is significant for chronic lymphocytic leukemia a few months ago for which he was started on chemotherapy. He has currently completed 3 cycles with the last one being few days ago. His temperature is 36.5°C (97.7°F), blood pressure is 118/75 mm Hg, pulse is 95/min, and respirations are 20/min. Lung are clear to auscultation bilaterally. There is severe tenderness to palpation over the right chest and a painful stripe of vesicular lesions, but no evidence of lesions, bruising or trauma. An electrocardiogram is normal and a chest radiograph is unremarkable. Cardiac enzymes are pending. Laboratory studies show:\nLaboratory test\nBUN 40 mg/dL\nSerum creatinine  3.0 mg/dL\n    Urinalysis\nProtein +\nGlucose absent\nRBC absent\nWBC 3/HPF\nNitrite absent\nLeukocyte esterase  negative\nSediments negative\nWhich of the following is the best course of treatment for this patient?", "answer": "Famciclovir", "options": {"A": "Cardiac catheterization", "B": "Ganciclovir", "C": "Acyclovir", "D": "Rest and NSAIDs", "E": "Famciclovir"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 21-year-old Caucasian woman presents to her gynecologist's office with a chief complaint of irregular periods. In the past 2 years, she has often gone > 3 months without menstruating. Menarche was at 13 years old, and prior to the past 2 years, she had regular periods every 28 days lasting 5 days with normal flow and no pain. She denies other symptoms of headache, vision changes, excessive fatigue or sweating, feelings of a racing heart, or hair loss. Since starting college, she has been bothered by weight gain and acne that she attributes to her habit of late night pizza and french fries. On exam she is well appearing with severe acne, and her temperature is 98.6°F (37°C), blood pressure is 120/80 mmHg, pulse is 60/min, and BMI is 30 kg/m^2. Lab work confirms the most likely diagnosis and includes a Hemoglobin A1c of 5.4. If she is not interested in child bearing at this time, what is the best initial medication to treat this disease?", "answer": "Ethinyl estradiol - norgestimate", "options": {"A": "Ethinyl estradiol - norgestimate", "B": "Leuprolide", "C": "Metformin", "D": "Spironolactone", "E": "Simvastatin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 41-year-old man presents at an office for a regular health check-up. He has no complaints. He has no history of significant illnesses. He currently takes omeprazole for gastroesophageal reflux disease. He occasionally smokes cigarettes and drinks alcohol. The family history is unremarkable. The vital signs include: blood pressure 133/67 mm Hg, pulse 67/min, respiratory rate 15/min, and temperature 36.7°C (98.0°F). The physical examination was within normal limits. A complete blood count reveals normal values. A urinalysis was ordered which shows the following:\npH 6.7\nColor light yellow\nRBC none\nWBC none\nProtein absent\nCast hyaline casts\nGlucose absent\nCrystal none\nKetone absent\nNitrite absent\nWhich of the following is the likely etiology for hyaline casts in this patient?", "answer": "Non-specific; can be a normal finding", "options": {"A": "Post-streptococcal glomerulonephritis", "B": "Non-specific; can be a normal finding", "C": "Acute interstitial nephritis", "D": "Nephrotic syndrome", "E": "End-stage renal disease/chronic kidney disease (CKD)"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old woman presents with blurry vision for the past 2 weeks. She says that symptoms onset gradually and have progressively worsened. She works as a secretary in a law firm, and now her vision is hampering her work. Past medical history is significant for psoriasis, diagnosed 7 years ago, managed with topical corticosteroids. Her blood pressure is 120/60 mm Hg, respiratory rate is 17/min, and pulse is 70/min. Her BMI is 28 kg/m2. Physical examination is unremarkable. Laboratory findings are significant for the following:\nRBC count 4.4 x 1012/L\nWBC count 5.0 x 109/L\nHematocrit 44%\nFasting plasma glucose 250 mg/dL\nHemoglobin A1C 7.8%\nWhich of the following would be the most likely cause of death in this patient?", "answer": "Myocardial infarction", "options": {"A": "Renal failure", "B": "Rhinocerebral mucormycosis", "C": "Peripheral neuropathy", "D": "Myocardial infarction", "E": "Coma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 46-year-old man who recently immigrated from Mexico comes to the physician for a pre-employment wellness examination. A tuberculin skin test is administered and he develops a raised, erythematous 12 mm lesion on his forearm within 48 hours. An x-ray of the chest shows no abnormalities. He is started on the recommended antibiotic treatment for latent tuberculosis. Four weeks later, he returns for a follow-up examination. Laboratory studies show a hemoglobin concentration of 9.3 g/dL, serum alanine aminotransferase activity of 86 U/L, and serum aspartate aminotransferase activity of 66 U/L. A photomicrograph of a Prussian blue-stained bone marrow smear is shown. Which of the following is the mechanism of action of the drug responsible for this patient's findings?", "answer": "Inhibition of mycolic acid synthesis", "options": {"A": "Inhibition of dihydropteroate synthase", "B": "Binding to 50S ribosomal subunit", "C": "Inhibition of bacterial RNA polymerase", "D": "Inhibition of mycolic acid synthesis", "E": "Inhibition of arabinosyltransferase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "In your peripheral tissues and lungs, carbonic anhydrase works to control the equilibrium between carbon dioxide and carbonic acid in order to maintain proper blood pH. Through which mechanism does carbonic anhydrase exert its influence on reaction kinetics?", "answer": "Lowers the activation energy", "options": {"A": "Lowers the activation energy", "B": "Changes the delta G of the reaction", "C": "Raises the activation energy", "D": "Lowers the free energy of products", "E": "Lowers the free energy of reactants"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 10-year-old boy is brought to the emergency department for the evaluation of one episode of vomiting and severe headache since this morning. His mother says he also had difficulty getting dressed on his own. He has not had any trauma. The patient appears nervous. His temperature is 37°C (98.6°F), pulse is 100/min, and blood pressure is 185/125 mm Hg. He is confused and oriented only to person. Ophthalmic examination shows bilateral optic disc swelling. There is an abdominal bruit that is best heard at the right costovertebral angle. A complete blood count is within normal limits. Which of the following is most likely to confirm the diagnosis?", "answer": "CT angiography", "options": {"A": "Echocardiography", "B": "Oral sodium loading test", "C": "CT angiography", "D": "Serum IGF-I level", "E": "High-dose dexamethasone suppression test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old man is brought to the emergency room by his roommate after he was found attempting to commit suicide. His roommate says that he stopped him before he was about to jump off the balcony. He has been receiving treatment for depression for about a year. 6 months ago, he had come to the hospital reporting decreased interest in his daily activities and inability to concentrate on his work. He had stopped going out or accepting invitations for any social events. He spent several nights tossing and turning in bed. He also expressed guilt for being unable to live up to his parents’ expectations. His psychiatrist started him on fluoxetine. He says that none of the medications have helped even though the dose of his medication was increased on several occasions, and he was also switched to other medications over the course of the past year. He has mentioned having suicidal thoughts due to his inability to cope with daily activities, but this is the first time he has ever attempted it. Which of the following would this patient be a suitable candidate for?", "answer": "Electroconvulsive therapy", "options": {"A": "Cognitive behavioral theory", "B": "Electroconvulsive therapy", "C": "Exposure therapy", "D": "Amitriptyline", "E": "Olanzapine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old male presents to the emergency department following several days of facial edema. A urinalysis confirms proteinuria and hematuria. Once admitted, a kidney biopsy is viewed under an electron microscope to confirm the diagnosis of minimal change disease. In the following electron micrograph, what process occurs in the structure marked with an arrow?", "answer": "rRNA is produced", "options": {"A": "Proteins are synthesized for extracellular secretion", "B": "Translation occurs", "C": "rRNA is produced", "D": "Assembly of the 80S ribosome", "E": "Initiation factors bind RNA"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old man who works as a resident in general surgery presents feeling \"burned out\" for the last 2 months. He says he has been working extremely long hours under stressful conditions, which makes him irritable, edgy, unfocused, and forgetful. He says he also has severe anxiety about how these symptoms are affecting his performance at work, making it difficult for him to sleep even when he has time off. The patient is referred for counseling and is prescribed some mild sleep aids. At follow-up a few months later, he says he is feeling much improved due to improved staffing at the hospital and a more manageable workload. Which of the following is the most likely diagnosis in this patient?", "answer": "Adjustment disorder", "options": {"A": "Adjustment disorder", "B": "Generalized anxiety disorder", "C": "Anxiety disorder", "D": "Panic disorder", "E": "Normal human behavior"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old woman presents with changes in her left breast that started 1 month ago. The patient states that she noticed that an area of her left breast felt thicker than before, and has not improved. She came to get it checked out because her best friend was just diagnosed with invasive ductal carcinoma. The past medical history is significant for Hashimoto’s thyroiditis, well-managed medically with levothyroxine. The patient has a 30-pack-year smoking history, but she quit over 15 years ago. The menarche occurred at age 11, and the menopause was at age 53. She does not have any children and has never been sexually active. Her last screening mammogram 10 months ago was normal. The family history is significant for her mother dying from a myocardial infarction (MI) at age 68, her sister dying from metastatic breast cancer at age 55, and for colon cancer in her paternal grandfather. The review of systems is notable for unintentional weight loss of 3.6 kg (8 lb) in the past month. The vital signs include: temperature 37.0℃ (98.6℉), blood pressure 110/70 mm Hg, pulse 72/min, respiratory rate 15/min, and oxygen saturation 98% on room air. The physical examination is significant only for a minimally palpable mass with irregular, poorly defined margins in the upper outer quadrant of the left breast. The mass is rubbery and movable. There is no axillary lymphadenopathy noted. Which of the following characteristics is associated with this patient’s most likely type of breast cancer in comparison to her friend’s diagnosis?", "answer": "Can present bilaterally", "options": {"A": "Worse prognosis", "B": "Can present bilaterally", "C": "Higher prevalence", "D": "Mammogram is more likely to demonstrate a discrete spiculated mass", "E": "Fibrosis is a distinguishing feature on biopsy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-year-old boy is brought to the emergency department due to a severe infection. Laboratory work shows leukocytosis of 60 × 109/L with marked left shift, but no blast cells. The patient is febrile and dehydrated. The physician believes that this is a severe reaction to the infection and orders a leukocyte alkaline phosphatase (LAP) stain on a peripheral smear. The LAP score is elevated. Which of the following statements best describes an additional characteristic of the condition this child is suffering from?", "answer": "A blood count will contain band forms, metamyelocytes, and myelocytes.", "options": {"A": "This condition can lead to chronic myelocytic leukemia.", "B": "Myeloblasts and promyelocytes are expected to be found.", "C": "A blood count will contain band forms, metamyelocytes, and myelocytes.", "D": "Chemotherapy is the treatment of choice.", "E": "The patient may develop anemia secondary to infection."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old male visits his physician because of fertility issues with his wife. Physical exam reveals bilateral gynecomastia, elongated limbs, and shrunken testicles. Levels of plasma gonadotropins are elevated. Which of the following is also likely to be increased in this patient:", "answer": "Aromatase", "options": {"A": "Testosterone", "B": "Inhibin", "C": "Aromatase", "D": "Ejaculatory sperm", "E": "Sertoli cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 7-year-old boy is brought to the physician by his parents because of a 4.5-kg (10-lb) weight loss during the last 3 months. During this period, he has complained of abdominal pain and fullness, and his parents feel that he has been eating less. His parents also report that his urine has appeared pink for several weeks. He has been performing poorly in school lately, with reports from teachers that he has not been paying attention in class and has been distracting to other students. He was born at term and has been healthy except for a history of several infantile seizures. His vital signs are within normal limits. He is at the 60th percentile for height and 20th percentile for weight. Physical examination shows a palpable abdominal mass, abdominal tenderness in the left upper quadrant, and left costovertebral angle tenderness. There are several ellipsoid, hypopigmented macules on the back and legs and a 4-cm raised plaque of rough, dimpled skin on the right lower back that is the same color as the surrounding skin. Which of the following is the most likely diagnosis?", "answer": "Tuberous sclerosis", "options": {"A": "Von Hippel‑Lindau disease", "B": "Neurofibromatosis type 1", "C": "Sturge-Weber syndrome", "D": "Tuberous sclerosis", "E": "Neurofibromatosis type 2"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 9-month-old boy is brought to the pediatrician because he can not sit on his own without support and has involuntary movements. He was born vaginally with no complications at full term. There is no history of consanguinity among parents. On physical examination, it was noticed that he is a stunted infant with generalized hypotonia and severe generalized dystonic movements. The mother says that she has noticed the presence of orange sand in his diapers many times. Laboratory evaluation revealed elevated uric acid levels in both blood and urine. Hypoxanthine-guanine phosphoribosyltransferase is found to be deficient in his blood samples. He was prescribed an appropriate medication and sent home. The most likely mechanism of this drug is the inhibition of which of the following enzymes in addition to xanthine oxidase?", "answer": "Purine nucleoside phosphorylase", "options": {"A": "Purine nucleoside phosphorylase", "B": "Orotate phosphoribosyltransferase", "C": "Ribonucleotide reductase", "D": "Inosine monophosphate dehydrogenase", "E": "Dihydrofolate reductase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old man presents to the emergency department with acute onset of pain and redness of the skin of his lower leg for the past 3 days. He has had type 2 diabetes mellitus for the past 12 years, but he is not compliant with his medications. He has smoked 10–15 cigarettes per day for the past 20 years. His temperature is 38°C (100.4°F), pulse is 95/min, and blood pressure is 110/70 mm Hg. On physical examination, the pretibial area is erythematous, edematous, and tender. He is diagnosed with acute cellulitis, and intravenous ceftazidime sodium is started. On the 5th day of antibiotic therapy, the patient complains of severe watery diarrhea, fever, and abdominal tenderness without rigidity. Complete blood count is ordered for the patient and shows 14,000 white blood cells/mm3. Which of the following is the best initial therapy for this patient?", "answer": "Oral vancomycin", "options": {"A": "Intravenous vancomycin", "B": "Oral vancomycin", "C": "Oral metronidazole", "D": "Oral ciprofloxacin", "E": "Fecal microbiota transplantation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "At postpartum physical examination, a newborn is found to have male external genitalia. Scrotal examination shows a single palpable testicle in the right hemiscrotum. Ultrasound of the abdomen and pelvis shows an undescended left testis, seminal vesicles, uterus, and fallopian tubes. Chromosomal analysis shows a 46, XY karyotype. Which of the following sets of changes is most likely to be found in this newborn?\n $$$ SRY-gene activity %%% Müllerian inhibitory factor (MIF) %%% Testosterone %%% Dihydrotestosterone (DHT) $$$", "answer": "Normal ↓ normal normal", "options": {"A": "↓ ↓ ↓ ↓", "B": "Normal normal ↑ ↑", "C": "↓ ↓ normal normal", "D": "Normal ↓ normal normal", "E": "Normal normal normal ↓"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3080-g (6-lb 13-oz) male newborn is delivered at term to a 27-year-old woman, gravida 2, para 1. Pregnancy was uncomplicated. He appears pale. His temperature is 36.8°C (98.2°F), pulse is 167/min, and respirations are 56/min. Examination shows jaundice of the skin and conjunctivae. The liver is palpated 2–3 cm below the right costal margin, and the spleen is palpated 1–2 cm below the left costal margin. The lungs are clear to auscultation. No murmurs are heard. His hemoglobin concentration is 10.6 g/dL and mean corpuscular volume is 73 μm3. Hemoglobin DNA testing shows 3 missing alleles. Which of the following laboratory findings is most likely present in this patient?", "answer": "Increased hemoglobin Barts concentration", "options": {"A": "Low reticulocyte count", "B": "Elevated HbF", "C": "Low serum ferritin", "D": "Increased hemoglobin Barts concentration", "E": "Elevated HbA2\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 31-year-old woman presents with dysuria and pain in the lower abdomen. It is the first time she has experienced such symptoms. She denies a history of any genitourinary or gynecologic diseases. The blood pressure is 120/80 mm Hg, heart rate is 78/min, respiratory rate is 13/min, and temperature is 37.0°C (98.6°F). The physical examination is within normal limits. A urine culture grew the pathogens pictured. The presence of which of the following factors specifically allows this pathogen to cause urinary tract infections?", "answer": "P-fimbriae", "options": {"A": "P-fimbriae", "B": "K-capsule", "C": "Heat-labile toxin", "D": "Heat-stable toxin", "E": "Hemolysin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 44-year-old woman presents to the outpatient clinic for the evaluation of amenorrhea which she noted roughly 4 months ago. Her monthly cycles up to that point were normal. Initially, she thought that it was related to early menopause; however, she has also noticed that she has a small amount of milk coming from her breasts as well. She denies any nausea, vomiting, or weight gain but has noticed that she has lost sight in the lateral fields of vision to the left and right. Her vital signs are unremarkable. Physical examination confirms bitemporal hemianopsia. What test is likely to reveal her diagnosis?", "answer": "MRI brain", "options": {"A": "Urine pregnancy test", "B": "MRI brain", "C": "Serum estrogen and progesterone levels", "D": "Mammogram", "E": "Serum TSH and free T4"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man is rushed to the emergency department by his wife after complaining of sudden onset, an excruciating headache that started about an hour ago. On further questioning, the patient’s wife gives a prior history of flank pain, hematuria, and hypertension in the patient, and she recalls that similar symptoms were present in his uncle. On examination, his GCS is 12/15, and when his hip joint and knee are flexed, he resists the subsequent extension of the knee. When the neck is flexed there is severe neck stiffness and it causes a patient’s hips and knees to flex. During the examination, he lapses into unconsciousness. Which of the following mechanisms best explains what led to this patient's presentation? ", "answer": "Increased wall tension within an aneurysm", "options": {"A": "Embolic occlusion of a cerebral vessel", "B": "Increased wall tension within an aneurysm", "C": "Intracerebral hemorrhage due to vascular malformations", "D": "Meningeal irritation from a space occupying lesion", "E": "Uremic encephalopathy from chronic renal disease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old woman comes to the physician because of a 6-month history of worsening shortness of breath and fatigue. Her paternal uncle had similar symptoms and died of respiratory failure at 45 years of age. The lungs are clear to auscultation. Pulmonary function testing shows an FVC of 84%, an FEV1/FVC ratio of 92%, and a normal diffusion capacity. An ECG shows a QRS axis greater than +90 degrees. Genetic analysis shows an inactivating mutation in the bone morphogenetic protein receptor type II (BMPR2) gene. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Elevated pulmonary arterial pressure", "options": {"A": "Chronic intravascular hemolysis", "B": "Elevated left atrial pressure", "C": "Fibrosis of the pulmonary parenchyma", "D": "Thickening of the interventricular septum", "E": "Elevated pulmonary arterial pressure"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-year-old girl is referred to the pediatrician after a primary care practitioner found her to be anemic, in addition to presenting with decreased bowel movements, intermittent abdominal pain, and hearing loss. The child has also shown poor performance at school and has lost interest in continuing her classes of glazed pottery that she has taken twice a week for the past year. During the examination, the pediatrician identifies gingival lines, generalized pallor, and moderate abdominal pain. Laboratory tests show elevated iron and ferritin concentration, and a blood smear shows small and hypochromic erythrocytes, basophilic stippling, and the presence of nucleated erythroblasts with granules visualized with Prussian blue. Which of the following molecules cannot be produced in the erythrocytes of this patient?", "answer": "Porphobilinogen", "options": {"A": "Coproporphyrinogen", "B": "Aminolevulinic acid", "C": "Hydroxymethylbilane", "D": "Porphobilinogen", "E": "Protoporphyrin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 10-year-old boy presents to the emergency department with sudden shortness of breath. He was playing in the school garden and suddenly started to complain of abdominal pain. He then vomited a few times. An hour later in the hospital, he slowly developed a rash on his chest, arms, and legs. His breathing became faster with audible wheezing. On physical examination, his vital signs are as follows: the temperature is 37.0°C (98.6°F), the blood pressure is 100/60 mm Hg, the pulse is 130/min, and the respiratory rate is 25/min. A rash is on his right arm, as shown in the image. After being administered appropriate treatment, the boy improves significantly, and he is able to breathe comfortably. Which of the following is the best marker that could be measured in the serum of this boy to help establish a definitive diagnosis?", "answer": "Tryptase", "options": {"A": "Prostaglandin D2", "B": "Serotonin", "C": "Histamine", "D": "Tryptase", "E": "Leukotrienes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old African American woman comes to the physician because of fatigue and muscle weakness for the past 5 weeks. During this period, she has had recurrent headaches and palpitations. She has hypertension and major depressive disorder. She works as a nurse at a local hospital. She has smoked about 6–8 cigarettes daily for the past 10 years and drinks 1–2 glasses of wine on weekends. Current medications include enalapril, metoprolol, and fluoxetine. She is 160 cm (5 ft 6 in) tall and weighs 60 kg (132 lb); BMI is 21.3 kg/m2. Her temperature is 37°C (98.6°F), pulse is 75/min, and blood pressure is 155/85 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft and nontender; bowel sounds are normal. Her skin is dry and there is no edema in the lower extremities. Laboratory studies show:\nHemoglobin 13.3 g/dL\nSerum\nNa+ 146 mEq/L\nCl- 105 mEq/L\nK+ 3.0 mEq/L\nHCO3- 30 mEq/L\nUrea nitrogen 10 mg/dL\nGlucose 95 mg/dL\nCreatinine 0.8 mg/dL\nUrine\nBlood negative\nGlucose negative\nProtein negative\nRBC 0–1/hpf\nWBC none\nWhich of the following is the most likely diagnosis in this patient?\"", "answer": "Aldosteronoma", "options": {"A": "Laxative abuse", "B": "Aldosteronoma", "C": "Renal artery stenosis", "D": "Pheochromocytoma", "E": "Cushing syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 31 year-old-man presents to an urgent care clinic with symptoms of lower abdominal pain, bloating, bloody diarrhea, and fullness, all of which have become more frequent over the last 3 months. His vital signs are as follows: blood pressure is 121/81 mm Hg, heart rate is 87/min, and respiratory rate is 15/min. Rectal examination reveals a small amount of bright red blood. Lower endoscopy is performed, showing extensive mucosal erythema, induration, and pseudopolyps extending from the rectum to the splenic flexure. Given the following options, what is the definitive treatment for this patient’s underlying disease?", "answer": "Total proctocolectomy", "options": {"A": "Sulfasalazine", "B": "Mesalamine", "C": "Systemic corticosteroids", "D": "Azathioprine", "E": "Total proctocolectomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A woman presents to the emergency department due to abdominal pain that began 1 hour ago. She is in the 35th week of her pregnancy when the pain came on during dinner. She also noted a clear rush of fluid that came from her vagina. The patient has a past medical history of depression which is treated with cognitive behavioral therapy. Her temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 100/min, respirations are 17/min, and oxygen saturation is 98% on room air. On physical exam, you note a healthy young woman who complains of painful abdominal contractions that occur every few minutes. Laboratory studies are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\nLecithin/Sphingomyelin: 1.5\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following is the best next step in management?", "answer": "Betamethasone", "options": {"A": "Betamethasone", "B": "Terbutaline", "C": "Oxytocin", "D": "RhoGAM", "E": "Expectant management"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Five days after undergoing a pancreaticoduodenectomy for pancreatic cancer, a 46-year-old woman has 2 episodes of non-bilious vomiting and mild epigastric pain. She has a patient-controlled analgesia pump. She has a history of hypertension. She has smoked one pack of cigarettes daily for 25 years. She drinks 3–4 beers daily. Prior to admission to the hospital, her only medications were amlodipine and hydrochlorothiazide. Her temperature is 37.8°C (100°F), pulse is 98/min, and blood pressure is 116/82 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Examination shows a midline surgical incision over the abdomen with minimal serous discharge and no erythema. The abdomen is soft with mild tenderness to palpation in the epigastrium. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11.6 g/dL\nLeukocyte count 16,000/mm3\nSerum\nNa+ 133 mEq/L\nK+ 3.4 mEq/L\nCl- 115 mEq/L\nGlucose 77 mg/dL\nCreatinine 1.2 mg/dL\nArterial blood gas on room air shows:\npH 7.20\npCO2 23 mm Hg\npO2 91 mm Hg\nHCO3- 10 mEq/L\nWhich of the following is the most likely cause of this patient's acid-base status?\"", "answer": "Fistula", "options": {"A": "Adrenal insufficiency", "B": "Excessive alcohol intake", "C": "Rhabdomyolysis", "D": "Adverse effect of medication", "E": "Fistula"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 44-year-old woman presents to the emergency department with jaundice and diffuse abdominal pain. She denies any previous medical problems and says she does not take any medications, drugs, or supplements. Her temperature is 97.6°F (36.4°C), blood pressure is 133/87 mmHg, pulse is 86/min, respirations are 22/min, and oxygen saturation is 100% on room air. Physical exam is notable for sclera which are icteric and there is tenderness to palpation over the right upper quadrant. Laboratory studies are ordered as seen below.\n\nHepatitis B surface antigen: Positive\nHepatitis B surface IgG: Negative\nHepatitis B core antigen: Positive\nHepatitis B core IgG: Positive\nHepatitis B E antigen: Positive\nHepatitis B E IgG: Positive\n\nWhich of the following is the most likely diagnosis?", "answer": "Chronic hepatitis B infection", "options": {"A": "Acute hepatitis B infection", "B": "Chronic hepatitis B infection", "C": "Hepatitis B vaccination", "D": "No hepatitis B vaccination or infection", "E": "Resolved hepatitis B infection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old woman presents to the emergency department complaining of a left-sided headache and right-sided blurry vision. She states that 2 weeks ago she developed dark urine and abdominal pain. She thought it was a urinary tract infection so she took trimethoprim-sulfamethoxazole that she had left over. She planned on going to her primary care physician today but then she developed headache and blurry vision so she came to the emergency department. The patient states she is otherwise healthy. Her family history is significant for a brother with sickle cell trait. On physical examination, there is mild abdominal tenderness, and the liver edge is felt 4 cm below the right costal margin. Labs are drawn as below:\n\nHemoglobin: 7.0 g/dL\nPlatelets: 149,000/mm^3\nReticulocyte count: 5.4%\nLactate dehydrogenase: 3128 U/L\n\nTotal bilirubin: 2.1 mg/dL\nIndirect bilirubin: 1.4 mg/dL\nAspartate aminotransferase: 78 U/L\nAlanine aminotransferase: 64 U/L\n\nA peripheral smear shows polychromasia. A Doppler ultrasound of the liver shows decreased flow in the right hepatic vein. Magnetic resonance imaging of the brain is pending. Which of the following tests, if performed, would most likely identify the patient’s diagnosis?", "answer": "Flow cytometry", "options": {"A": "Anti-histone antibodies", "B": "Bone marrow biopsy", "C": "Flow cytometry", "D": "Glucose-6-phosphate-dehydrogenase levels", "E": "Hemoglobin electrophoresis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old woman presents to her primary care physician with 3 weeks of palpitations and shortness of breath while exercising. She says that these symptoms have been limiting her ability to play recreational sports with her friends. Her past medical history is significant for pharyngitis treated with antibiotics and her family history reveals a grandfather who needed aortic valve replacements early due to an anatomic abnormality. She admits to illicit drug use in college, but says that she stopped using drugs 4 years ago. Physical exam reveals a clicking sound best heard in the left 6th intercostal space. This sound occurs between S1 and S2 and is followed by a flow murmur. Which of the following is most likely associated with the cause of this patient's disorder?", "answer": "Increased valvular dermatan sulfate", "options": {"A": "Bicuspid aortic valve", "B": "Increased valvular dermatan sulfate", "C": "Infection with Streptococcus pyogenes", "D": "Intravenous drug abuse", "E": "Mutation in cardiac contractile proteins"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old woman comes to the physician because of a 3-day history of dry cough and low-grade fever. Four months ago, she was diagnosed with major depressive disorder and started treatment with fluoxetine. Physical examination shows no abnormalities. A diagnosis of upper respiratory infection is made and a medication is prescribed to relieve her symptoms. A drug with which of the following mechanisms of action should be avoided in this patient?", "answer": "Inhibition of NMDA glutamate receptors", "options": {"A": "Disruption of mucoid disulfide bonds", "B": "Inhibition of H1 receptors", "C": "Reduction in secretion viscosity", "D": "Inhibition of NMDA glutamate receptors", "E": "Stimulation of α-adrenergic receptors"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man is brought to the emergency department by his wife after falling down. About 90 minutes ago, they were standing in their kitchen making lunch and chatting when he suddenly complained that he could not see as well, felt weak, and was getting dizzy. He began to lean to 1 side, and he eventually fell to the ground. He did not hit his head. In the emergency department, he is swaying while seated, generally leaning to the right. The general physical exam is unremarkable. The neurologic exam is notable for horizontal nystagmus, 3/5 strength in the right arm, ataxia of the right arm, and absent pinprick sensation in the left arm and left leg. The computed tomography (CT) scan of the head is unremarkable. Which of the following is the most likely single location of this patient's central nervous system lesion?", "answer": "Lateral medulla", "options": {"A": "Anterior spinal cord", "B": "Lateral medulla", "C": "Primary motor cortex", "D": "Primary somatosensory cortex", "E": "Thalamus"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 77-year-old Caucasian woman presents to her primary care provider for a general checkup. The patient is with her daughter who brought her to this appointment. The patient states that she is doing well and has some minor joint pain in both hips. She states that sometimes she is sad because her husband recently died. She lives alone and follows a vegan diet. The patient's daughter states that she has noticed her mother struggling with day to day life. It started 2 years ago with her forgetting simple instructions or having difficulty running errands. Now the patient has gotten to the point where she can no longer pay her bills. Sometimes the patient forgets how to get home. The patient has a past medical history of obesity, hypertension, gastroesophageal reflux disease (GERD) controlled with pantoprazole, and diabetes mellitus. Her temperature is 99.5°F (37.5°C), blood pressure is 158/108 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Which of the following will most likely help with this patient's presentation?", "answer": "Donepezil", "options": {"A": "Donepezil", "B": "Fluoxetine and cognitive behavioral therapy", "C": "Lisinopril and metoprolol", "D": "Vitamin B12 and discontinue pantoprazole", "E": "No intervention needed"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 33-year-old woman presents to her primary care physician for non-bloody nipple discharge. She states that it has been going on for the past month and that it sometimes soils her shirt. The patient drinks 2 to 3 alcoholic beverages per day and smokes 1 pack of cigarettes per day. She is currently seeking mental health treatment with an outpatient psychiatrist after a recent hospitalization for auditory hallucinations. Her psychiatrist prescribed her a medication that she can not recall. Otherwise, she complains of headaches that occur frequently. Her temperature is 98.6°F (37.0°C), blood pressure is 137/68 mmHg, pulse is 70/min, respirations are 13/min, and oxygen saturation is 98% on room air. Physical exam is notable for bilateral galactorrhea that can be expressed with palpation. Which of the following is the best next step in management?", "answer": "TSH level", "options": {"A": "CT scan of the head", "B": "Discontinuation of current psychiatric medications", "C": "Mammography", "D": "TSH level", "E": "Ultrasound and biopsy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old man is brought to the physician by his wife for the evaluation of abnormal sleep patterns that began 10 days ago. She reports that he has only been sleeping 2–3 hours nightly during this time and has been jogging for long periods of the night on the treadmill. The patient has also been excessively talkative and has missed work on several occasions to write emails to his friends and relatives to convince them to invest in a new business idea that he has had. He has chronic kidney disease requiring hemodialysis, but he has refused to take his medications because he believes that he is cured. Eight months ago, he had a 3-week long period of persistent sadness and was diagnosed with major depressive disorder. Mental status examination shows psychomotor agitation and pressured speech. Treatment of this patient's condition should include which of the following drugs?", "answer": "Valproate", "options": {"A": "Buproprion", "B": "Triazolam", "C": "Valproate", "D": "Mirtazapine", "E": "Fluoxetine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old high school student is brought to the emergency department because of irritability and rapid breathing. He appears agitated and is diaphoretic. His temperature is 38.3°C (101°F), pulse is 129/min, respirations are 28/min, and blood pressure is 158/95 mmHg. His pupils are dilated. An ECG shows sinus tachycardia. Which of the following substances is used to make the drug this patient has most likely taken?", "answer": "Pseudoephedrine", "options": {"A": "Ergotamine", "B": "Pseudoephedrine", "C": "Homatropine", "D": "Sodium oxybate", "E": "Codeine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old man is brought to the emergency department because of a 30-minute history of dizziness and shortness of breath. After establishing the diagnosis, treatment with a drug is administered. Shortly after administration, the patient develops severe left eye pain and decreased vision of the left eye, along with nausea and vomiting. Ophthalmologic examination shows a fixed, mid-dilated pupil and a narrowed anterior chamber of the left eye. The patient was most likely treated for which of the following conditions?", "answer": "Atrioventricular block", "options": {"A": "Atrioventricular block", "B": "Hypertensive crisis", "C": "Mitral regurgitation", "D": "Pulmonary embolism", "E": "Viral pleuritis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the pediatrician by her parents after her mother recently noticed that other girls of similar age talk much more than her daughter. Her mother reports that her language development has been abnormal and she was able to use only 5–6 words at the age of 2 years. Detailed history reveals that she has never used her index finger to indicate her interest in something. She does not enjoy going to birthday parties and does not play with other children in her neighborhood. The mother reports that her favorite “game” is to repetitively flex and extend the neck of a doll, which she always keeps with her. She is sensitive to loud sounds and starts screaming excessively when exposed to them. There is no history of delayed motor development, seizures, or any other major illness; perinatal history is normal. When she enters the doctor’s office, the doctor observes that she does not look at him. When he gently calls her by her name, she does not respond to him and continues to look at her doll. When the doctor asks her to look at a toy on his table by pointing a finger at the toy, she looks at neither his finger nor the toy. The doctor also notes that she keeps rocking her body while in the office. Which of the following is an epidemiological characteristic of the condition the girl is suffering from?", "answer": "This condition is 4 times more common in boys than girls.", "options": {"A": "This condition is 4 times more common in boys than girls.", "B": "There is an increased incidence if the mother gives birth before 25 years of age.", "C": "There has been a steady decline in prevalence in the United States over the last decade.", "D": "There is an increased risk if the mother smoked during pregnancy.", "E": "There is an increased risk with low prenatal maternal serum vitamin D level."}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 85-year-old man with hypertension and type 2 diabetes mellitus is brought to the emergency department because of a 2-day history of shortness of breath. He has smoked one pack of cigarettes daily for 30 years. His temperature is 36.9°C (98.4°F), pulse is 100/min, respirations are 30/min, and blood pressure is 138/75 mm Hg. Pulmonary function testing shows decreased tidal volume and normal lung compliance. Which of the following is the most likely underlying etiology of this patient's tachypnea?", "answer": "Rib fracture", "options": {"A": "Emphysema exacerbation", "B": "Tension pneumothorax", "C": "Diabetic ketoacidosis", "D": "Rib fracture", "E": "Pulmonary edema"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2-year-old boy is brought to the emergency department because of fever, fatigue, and productive cough for the past 2 days. He had similar symptoms 6 months ago when he was diagnosed with pneumonia. Three weeks ago, he was diagnosed with otitis media for the 6th time since birth and was treated with amoxicillin. His temperature is 38.7°C (101.7°F), the pulse is 130/min, the respirations are 36/min, and the blood pressure is 84/40 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 93%. Examination shows purulent discharge in the left ear canal and hypoplastic tonsils without exudate. Coarse crackles are heard over the right lung field on auscultation. An X-ray of the chest shows a right-middle lobe consolidation. Flow cytometry shows absent B cells and normal T cells. Which of the following is the most appropriate next step in management?", "answer": "Intravenous immunoglobulins", "options": {"A": "Combined antiretroviral therapy", "B": "Intravenous immunoglobulins", "C": "Recombinant human granulocyte-colony stimulating factor administration", "D": "Stem cell transplantation", "E": "Thymus transplantation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old man comes to the physician for recurrent heartburn for 12 years. He has also developed a cough for a year, which is worse at night. He has smoked a pack of cigarettes daily for 30 years. His only medication is an over-the-counter antacid. He has not seen a physician for 8 years. He is 175 cm (5 ft 9 in) tall and weighs 95 kg (209 lb); BMI is 31 kg/m2. Vital signs are within normal limits. There is no lymphadenopathy. The abdomen is soft and nontender. The remainder of the examination shows no abnormalities. A complete blood count is within the reference range. An upper endoscopy shows columnar epithelium 2 cm from the gastroesophageal junction. Biopsies from the columnar epithelium show low-grade dysplasia and intestinal metaplasia. Which of the following is the most appropriate next step in management?", "answer": "Endoscopic therapy", "options": {"A": "Repeat endoscopy in 18 months", "B": "Endoscopic therapy", "C": "Omeprazole, clarithromycin, and metronidazole therapy", "D": "External beam radiotherapy", "E": "Nissen fundoplication"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old man of Mediterranean descent makes an appointment with his physician because his skin and sclera have become yellow. He complains of fatigue and fever that started at the same time icterus appeared. On examination, he is tachycardic and tachypneic. The oxygen (O2) saturation is < 90%. He has increased unconjugated bilirubin, hemoglobinemia, and an increased number of reticulocytes in the peripheral blood. What is the most likely diagnosis?", "answer": "Hemolytic anemia caused by glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency)", "options": {"A": "Hemolytic anemia caused by glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency)", "B": "Anemia caused by renal failure", "C": "Autoimmune hemolytic anemia (AIHA)", "D": "Microcytic anemia caused by iron deficiency", "E": "Aplastic anemia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man comes to a follow-up appointment with his surgeon 2 months after undergoing hip replacement surgery. His major concern at this visit is that he is still limping since the surgery even after the post-operative pain has subsided. Specifically, when he stands on his right leg, he feels that he has to lean further to the right in order to maintain balance. When standing on his left leg, he feels that he is able to step normally. Damage to which of the following nerves would most likely present with this patient's symptoms?", "answer": "Superior gluteal nerve", "options": {"A": "Common peroneal nerve", "B": "Femoral nerve", "C": "Inferior gluteal nerve", "D": "Superior gluteal nerve", "E": "Tibial nerve"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man presents to his primary care physician for diarrhea. He states that he has experienced roughly 10 episodes of non-bloody and watery diarrhea every day for the past 3 days. The patient has a past medical history of IV drug abuse and recently completed treatment for an abscess with cellulitis. His vitals are notable for a pulse of 105/min. Physical exam reveals diffuse abdominal discomfort with palpation but no focal tenderness. A rectal exam is within normal limits and is Guaiac negative. Which of the following is the best initial treatment for this patient?", "answer": "Vancomycin", "options": {"A": "Clindamycin", "B": "Fidaxomicin", "C": "Metronidazole", "D": "Oral rehydration and discharge", "E": "Vancomycin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old Caucasian female presents with severe right lower quadrant pain, malaise, and diarrhea. The physician performs an endoscopy and finds disease involvement in the terminal ileum, noting that that the disease process is patchy with normal intervening mucosa. The entire wall of the region is thickened and inflamed, which may directly lead to formation of:", "answer": "Fistulas", "options": {"A": "Fistulas", "B": "Toxic megacolon", "C": "Widening of the intestinal lumen", "D": "Plummer-Vinson syndrome", "E": "Paneth cell metaplasia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old man is brought to the emergency department by his friends because of a 1-hour history of shortness of breath and squeezing chest pain. They were at a party where cocaine was consumed. A diagnosis of acute myocardial infarction is made. The physician stabilizes the patient and transfers him to the inpatient unit. Six hours later, his wife arrives at the emergency department and requests information about her husband's condition. Which of the following is the most appropriate action by the physician?", "answer": "Obtain authorization from the patient to release information", "options": {"A": "Obtain authorization from the patient to release information", "B": "Inform the wife about her husband's condition", "C": "Consult the hospital ethics committee", "D": "Request the patient's durable power of attorney document", "E": "Ask the wife for a marriage certificate"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 71-year-old, hospitalized man develops abnormal laboratory studies 4 days after starting treatment for exacerbation of congestive heart failure. He also has a history of osteoarthritis and benign prostatic hyperplasia. He recently completed a course of amikacin for bacterial prostatitis. Before hospitalization, his medications included simvastatin and ibuprofen. Blood pressure is 111/76 mm Hg. Serum studies show a creatinine of 2.3 mg/dL (previously normal) and a BUN of 48 mg/dL. Urinalysis shows a urine osmolality of 600 mOsm/kg and urine sodium of 10 mEq/L. Which of the following is the most likely explanation for this patient's renal insufficiency?", "answer": "Volume depletion", "options": {"A": "Volume depletion", "B": "Urinary tract infection", "C": "Bladder outlet obstruction", "D": "Glomerulonephritis", "E": "Antibiotic use"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old woman comes to the physician because of a 1-day history of right leg pain. The pain is worse while walking and improves when resting. Eight months ago, she was diagnosed with a pulmonary embolism and was started on warfarin. Anticoagulant therapy was discontinued two months ago. Her mother had systemic lupus erythematosus. On examination, her right calf is diffusely erythematous, swollen, and tender. Cardiopulmonary examination shows no abnormalities. On duplex ultrasonography, the right popliteal vein is not compressible. Laboratory studies show an elevated serum level of D-dimer and insensitivity to activated protein C. Further evaluation of this patient is most likely to show which of the following?", "answer": "Mutation of coagulation factor V", "options": {"A": "Protein S deficiency", "B": "Elevated coagulation factor VIII levels", "C": "Mutation of prothrombin", "D": "Mutation of coagulation factor V", "E": "Deficiency of protein C\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old man is brought to the emergency department because of right-sided weakness for 2 hours. He has hypertension, dyslipidemia, and type 2 diabetes. Current medications include hydrochlorothiazide, metoprolol, amlodipine, pravastatin, and metformin. His pulse is 87/min and blood pressure is 164/98 mm Hg. Neurological examination shows right-sided weakness, facial droop, and hyperreflexia. Sensation is intact. Which of the following is the most likely cause of these findings?", "answer": "Lipohyalinosis of penetrating vessels", "options": {"A": "Rupture of an intracranial aneurysm", "B": "Lipohyalinosis of penetrating vessels", "C": "Dissection of the vertebral artery", "D": "Stenosis of the internal carotid artery", "E": "Embolism from the left atrium"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 59-year-old woman comes to the physician for a 3-month history of progressively worsening shortness of breath on exertion and swelling of her legs. She has a history of breast cancer, which was treated with surgery followed by therapy with doxorubicin and trastuzumab 4 years ago. Cardiac examination shows an S3 gallop; there are no murmurs or rubs. Examination of the lower extremities shows pitting edema below the knees. Echocardiography is most likely to show which of the following sets of changes in this patient?\n $$$ Ventricular wall thickness %%% Ventricular cavity size %%% Diastolic function %%% Aorto-ventricular pressure gradient $$$", "answer": "↓ ↑ normal normal", "options": {"A": "Normal normal ↓ normal", "B": "↑ ↑ normal normal", "C": "↑ ↓ ↓ normal", "D": "↑ ↓ ↓ ↑", "E": "↓ ↑ normal normal"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old female volunteers for an invasive study to measure her cardiac function. She has no previous cardiovascular history and takes no medications. With the test subject at rest, the following data is collected using blood tests, intravascular probes, and a closed rebreathing circuit:\nBlood hemoglobin concentration 14 g/dL\nArterial oxygen content 0.22 mL O2/mL\nArterial oxygen saturation 98%\nVenous oxygen content 0.17 mL O2/mL\nVenous oxygen saturation 78%\nOxygen consumption 250 mL/min\nThe patient's pulse is 75/min, respiratory rate is 14/ min, and blood pressure is 125/70 mm Hg. What is the cardiac output of this volunteer?", "answer": "5.0 L/min", "options": {"A": "250 mL/min", "B": "5.0 L/min", "C": "50 L/min", "D": "Stroke volume is required to calculate cardiac output.", "E": "Body surface area is required to calculate cardiac output."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old man, with a history of gluten intolerance, presents to the emergency department with persistent vomiting and diarrhea, and no fever. He recently returned from a vacation in Central America. He describes his diarrhea as profuse and almost clear. On physical examination, his skin turgor is decreased and his blood pressure is 90/60 mm Hg. He is administered a saline solution and admitted for further examination and observation. What shifts are expected to be seen in this patient’s Darrow-Yannet diagram before the administration of saline?", "answer": "Decreased extracellular volume with no change in osmolarity", "options": {"A": "Decreased extracellular volume and osmolality with an increased intracellular volume", "B": "Increased extracellular volume, increased osmolarity, and decreased intracellular volume", "C": "Decreased extracellular volume with no change in osmolarity", "D": "Increased extracellular volume with no change in osmolarity or intracellular volume", "E": "Decreased extracellular volume and intracellular volume with a rise in osmolality"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old woman comes to the physician because of 2 episodes of loss of consciousness over the past week. She recovered immediately and was not confused following the episodes. During the past 5 months, she has also had increased shortness of breath and palpitations. She has been unable to carry out her daily activities. She also reports some chest tightness that resolves with rest. She has no history of serious illness and takes no medications. She immigrated with her family from India 10 years ago. Her temperature is 37.3°C (99.1°F), pulse is 115/min and irregular, and blood pressure is 108/70 mm Hg. Examination shows jugular venous distention and pitting edema below the knees. Bilateral crackles are heard at the lung bases. Cardiac examination shows an accentuated and split S2. There is an opening snap followed by a low-pitched diastolic murmur in the fifth left intercostal space at the midclavicular line. An ECG shows atrial fibrillation and right axis deviation. Which of the following is the most likely underlying mechanism of these findings?", "answer": "Increased left atrial pressure", "options": {"A": "Increased left ventricular end diastolic pressure", "B": "Increased left to right shunting", "C": "Decreased left ventricular contractility", "D": "Increased systemic arterial resistance", "E": "Increased left atrial pressure"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old man with small cell lung cancer undergoes radiation therapy. His oncologist explains that radiation causes DNA damage and double strand breaks and this damage stops the cancer cells from growing because they can no longer replicate their DNA. One key mediator of this process is a cell cycle regulator called P53, which is upregulated after DNA damage and helps to trigger cell cycle arrest and apoptosis. One mechanism by which P53 activity is increased is a certain chromatin modification that loosens DNA coiling allowing for greater transcription of the proteins within that region of DNA. Which of the following enyzmes most likely causes the chromatin modification described in this case?", "answer": "Histone acetyltransferase", "options": {"A": "DNA methyltransferase", "B": "Histone acetyltransferase", "C": "Histone deacetylase", "D": "Histone methyltransferase", "E": "Xist"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old girl is brought to the physician because her mother has found her to be inattentive at home and has received multiple complaints from her teachers at school. She does not complete her assignments and does not listen to her teachers' instructions. She refuses to talk to her parents or peers. Her mother says, “She ignores everything I say to her!” She prefers playing alone, and her mother reports that she likes playing with 5 red toy cars, repeatedly arranging them in a straight line. She avoids eye contact with her mother and the physician throughout the visit. Physical and neurological examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Autism spectrum disorder", "options": {"A": "Attention deficit hyperactivity disorder", "B": "Oppositional defiant disorder", "C": "Autism spectrum disorder", "D": "Conduct disorder", "E": "Rett syndrome"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old man comes to the physician because of a 2-year-history of cough and progressively worsening breathlessness. He has smoked 1 pack of cigarettes daily for the past 10 years. Physical examination shows contraction of the anterior scalene and sternocleidomastoid muscles during inspiration. An x-ray of the chest shows flattening of the diaphragm and increased radiolucency in the lower lung fields. Further analysis shows increased activity of an isoform of elastase that is normally inhibited by alpha-1-antitrypsin. The cells that produce this isoform of elastase were most likely stimulated to enter the site of inflammation by which of the following substances?", "answer": "Leukotriene B4", "options": {"A": "High-molecular-weight kininogen", "B": "Lactoferrin", "C": "Interferon gamma", "D": "Leukotriene B4", "E": "Thromboxane A2"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old woman is brought to the emergency department by a paramedic team from the scene of a motor vehicle accident where she was the driver. The patient was restrained by a seat belt and was unconscious at the scene. On physical examination, the patient appears to have multiple injuries involving the trunk and extremities. There are no penetrating injuries to the chest. As part of her trauma workup, a CT scan of the chest is ordered. At what vertebral level of the thorax is this image from?", "answer": "T8", "options": {"A": "T4", "B": "T1", "C": "T5", "D": "T6", "E": "T8"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old woman presents with continuous feelings of sadness and rejection. She says that over the past couple of weeks, she has been unable to concentrate on her job and has missed several days of work. She also has no interest in any activity and typically rejects invitations to go out with friends. She has no interest in food or playing with her dog. Her husband is concerned about this change in behavior. A few months ago, she was very outgoing and made many plans with her friends. She remembers being easily distracted and also had several ‘brilliant ideas’ on what she should be doing with her life. She did not sleep much during that week, but now all she wants to do is lie in bed all day. She denies any suicidal or homicidal ideations. She has no past medical history and has never been hospitalized. Laboratory tests were normal. Which of the following is the most likely diagnosis in this patient?", "answer": "Bipolar disorder, type II", "options": {"A": "Dysthymia", "B": "Major depressive disorder", "C": "Schizoaffective disorder", "D": "Bipolar disorder, type II", "E": "Bipolar disorder, type I"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy with asthma is brought to the physician because of a 1-month history of worsening shortness of breath and cough. The mother reports that the shortness of breath usually occurs when he is exercising with his older brother. His only medication is an albuterol inhaler that is taken as needed. The physician considers adding zafirlukast to his drug regimen. Which of the following is the most likely mechanism of action of this drug?", "answer": "Antagonism at leukotriene receptors", "options": {"A": "Antagonism at leukotriene receptors", "B": "Inhibition of phosphodiesterase", "C": "Antagonism at muscarinic receptors", "D": "Inhibition of mast cell degranulation", "E": "Blockade of 5-lipoxygenase pathway"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman comes to the physician because she feels sad and has had frequent, brief episodes of crying for the last month. During this period, she sleeps in every morning and spends most of her time in bed playing video games or reading. She has not been spending time with friends but still attends a weekly book club and continues to plan her annual family reunion. She stopped going to the gym, eats more, and has gained 4 kg (8.8 lb) over the past 4 weeks. Three weeks ago, she also started to smoke marijuana a few times a week. She drinks one glass of wine daily and does not smoke cigarettes. She is currently unemployed; she lost her job as a physical therapist 3 months ago. Her vital signs are within normal limits. On mental status examination, she is calm, alert, and oriented to person, place, and time. Her mood is depressed; her speech is organized, logical, and coherent. She denies suicidal thoughts. Which of the following is the most likely diagnosis?", "answer": "Adjustment disorder", "options": {"A": "Adjustment disorder", "B": "Dysthymic disorder", "C": "Substance use disorder", "D": "Bipolar disorder", "E": "Major depressive disorder"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 63-old man is brought in by ambulance after a bar fight. Witnesses report that he is a bar regular and often drinks several shots of hard liquor throughout the night. The emergency department recognize him as a local homeless man with a long history of alcohol abuse. During the initial workup in the ED, he has a prolonged seizure and dies. An autopsy is performed that shows an enlarged heart with severe calcified atherosclerotic coronary arteries. Evaluation of his brain shows atrophic mammillary bodies with brown-tan discoloration. Which of the following tests would have most likely produced an abnormal result in vivo with respect to his nervous system findings on autopsy?", "answer": "Erythrocyte transketolase activity", "options": {"A": "CSF IgG protein", "B": "Rapid fluorescent spot test", "C": "Serum methylmalonic acid", "D": "Erythrocyte transketolase activity", "E": "Aldolase B activity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 56-year-old woman presents to her primary care physician complaining of heartburn, belching, and epigastic pain that is aggravated by coffee and fatty foods. She states that she has recently been having difficulty swallowing in addition to her usual symptoms. What is the most appropriate next step in management of this patient?", "answer": "Upper endoscopy", "options": {"A": "Trial of a proton pump inhibitor", "B": "Nissen fundoplication", "C": "Lifestyle changes - don't lie down after eating; avoid spicy foods; eat small servings", "D": "Trial of an H2 receptor antagonist", "E": "Upper endoscopy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 17-year-old boy is brought to the emergency department by his parents 6 hours after he suddenly began to experience dyspnea and pleuritic chest pain at home. He has a remote history of asthma in childhood but has not required any treatment since the age of four. His temperature is 98.4°F (36.9°C), blood pressure is 100/76 mmHg, pulse is 125/min, respirations are 24/min. On exam, he has decreased lung sounds and hyperresonance in the left upper lung field. A chest radiograph shows a slight tracheal shift to the right. What is the best next step in management?", "answer": "Needle decompression", "options": {"A": "Chest tube placement", "B": "CT scan for apical blebs", "C": "Needle decompression", "D": "Observe for another six hours for resolution", "E": "Pleurodesis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-month-old male infant is brought in because he rejects food and is losing weight. He had several upper respiratory tract infections during the last 2 months. Upon examination, hepatosplenomegaly is noted, as well as mild hypotonia. During the next few weeks, hepatosplenomegaly progresses, the boy fails to thrive, and he continues to reject food. He has a blood pressure of 100/70 mm Hg and heart rate of 84/min. Blood tests show pancytopenia and elevated levels of transaminases. Slit lamp examination shows bilateral cherry-red spots on the macula. Chest X-ray shows a reticulonodular pattern and calcified nodules. Biopsy of the liver shows foamy histiocytes. What is the most likely diagnosis?", "answer": "Niemann-Pick disease type A", "options": {"A": "Crigler-Najjar syndrome type I", "B": "Niemann-Pick disease type A", "C": "Gaucher disease", "D": "Primary biliary cirrhosis", "E": "Gilbert syndrome"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old man with a history of severe persistent asthma is seen today with the complaint of white patches on his tongue and inside his mouth. He says this all started a couple of weeks ago when he recently started a new medication for his asthma. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. His physical examination is significant for mild bilateral wheezes, and attempts at scraping off the lesions in the mouth are successful but leave erythema underlying where they were removed. Which of the following medications is responsible for his presentation?", "answer": "Beclomethasone inhaler", "options": {"A": "Over-use of the albuterol inhaler", "B": "Theophylline", "C": "Salmeterol inhaler", "D": "Beclomethasone inhaler", "E": "Omalizumab"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old male is brought to the emergency department 20 minutes after sustaining a stab wound to the right chest. First-responders found the patient sitting on the curb smoking a cigarette, complaining of pain where he had been stabbed. On arrival, he is alert. His temperature is 36.8°C (98.2°F), pulse is 110/min, respirations are 16/min, and blood pressure is 112/70 mmHg. Pulse oximetry on room air shows an oxygen saturation of 97%. Examination shows several 1–2 cm lacerations and ecchymoses over the face and trunk. There is no neck crepitus. There is a pocket knife in the right fourth intercostal space at the anterior axillary line and blood oozing out of the wound. There is no bubbling of the blood at the wound. The lungs are clear to auscultation with equal breath sounds. The remainder of the examination shows no abnormalities. A chest x-ray shows the knife in situ extending into the right thorax. Which of the following is the most appropriate next step in management?", "answer": "Endotracheal intubation", "options": {"A": "Right needle thoracostomy", "B": "Right tube thoracostomy", "C": "Endotracheal intubation", "D": "Cricothyroiditomy", "E": "CT scan of the chest"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old woman presents to the clinic complaining of a headache, runny nose, and malaise. A few minutes into the interview, she mentions that she recently started her job and is glad to work long hours despite the toll on her health. However, she admits that she is finding it difficult to keep up with the workload. She has numerous pending papers to correct. When advised to seek help from other teachers, she exclaims that it needs to be done in a particular way, and only she can do it the right way. This is causing her to perform poorly at work, and she is at risk of being asked to quit her very first job. Which of the following is the most likely diagnosis in this patient?", "answer": "Ego-syntonic obsessive-compulsive personality disorder", "options": {"A": "Ego-syntonic obsessive-compulsive personality disorder", "B": "Ego-dystonic obsessive-compulsive personality disorder", "C": "Ego-syntonic obsessive-compulsive disorder", "D": "Ego-dystonic obsessive-compulsive disorder", "E": "Personality disorder not otherwise specified"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old woman comes to the emergency department for a 1-week history of jaundice and nausea. She recalls eating some seafood last weekend at a cookout. She lives at home with her 2-year-old son who attends a daycare center. The child's immunizations are up-to-date. The woman's temperature is 37.5°C (99.5°F), pulse is 82/min, and blood pressure is 134/84 mm Hg. Examination shows scleral icterus. The liver is palpated 2-cm below the right costal margin and is tender. Her serum studies show:\nTotal bilirubin 3.4 mg/dL\nAlkaline phosphatase 89 U/L\nAST 185 U/L\nALT 723 U/L\nHepatitis A IgM antibody positive\nHepatitis B surface antibody positive\nHepatitis B surface antigen negative\nHepatitis B core IgM antibody negative\nHepatitis C antibody negative\nWhich of the following health maintenance recommendations is most appropriate for the child at this time?\"", "answer": "No additional steps are needed", "options": {"A": "Administer hepatitis B immunoglobulin and hepatitis B vaccine", "B": "Isolate the child", "C": "No additional steps are needed", "D": "Administer hepatitis B immunoglobulin only", "E": "Administer hepatitis A vaccine and hepatitis A immunoglobulin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old male immigrant with rheumatoid arthritis comes to the physician because of severe pain and swelling in both his knees. He also reports an unintentional weight loss of around 10 kg over 3 months and episodic abdominal pain, varying in intensity and location. He has been having loose stools with no blood, 2–3 times a day for 1 month. He denies fever, night sweats, cough, or shortness of breath. Current medications include methotrexate, naproxen, and folic acid. His weight is 68 kg (150 lbs), temperature is 37.4°C (99.3°F), pulse is 90/min, and blood pressure is 130/80 mm Hg. Examination shows pale conjunctivae, cheilitis, and hyperpigmentation of the skin around his neck. Generalized lymphadenopathy is present. Examination of the knee joints shows bilateral warmth, erythema, swelling, tenderness, and limited range of motion. A grade 2/6 early diastolic murmur is heard over the right second intercostal space and an S3 is heard. Abdominal examination shows no abnormalities. Laboratory studies show:\nHemoglobin 9.1 g/dL\nLeukocyte count 3800/mm3\nPlatelet count 140,000/mm3\nMean corpuscular volume 67 μm3\nErythrocyte sedimentation rate 62 mm/h\nSerum\nGlucose 100 mg/dL\nCreatinine 0.7 mg/dL\nTIBC 500 mcg/dL\nFerritin 10 mcg/dL\nRheumatoid factor negative\nAnti -CCP negative\nAn esophagogastroduodenoscopy is ordered. A biopsy specimen of the duodenum is likely to show which of the following?\"", "answer": "PAS-positive macrophages", "options": {"A": "Poorly differentiated cells", "B": "Granuloma with caseating necrosis", "C": "Villous atrophy and crypt hyperplasia", "D": "Noncaseating granulomas", "E": "PAS-positive macrophages"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 65-year-old man presents to the emergency department for shortness of breath. He was at home working on his car when he suddenly felt very short of breath, which failed to improve with rest. He states he was working with various chemicals and inhalants while trying to replace a broken piece in the engine. The patient was brought in by paramedics and is currently on 100% O2 via nasal cannula. The patient has a 52 pack-year smoking history and drinks 2 to 3 alcoholic drinks every night. He has a past medical history of asthma but admits to not having seen a physician since high school. His temperature is 98.2°F (36.8°C), blood pressure is 157/108 mmHg, pulse is 120/min, respirations are 29/min, and oxygen saturation is 77%. Physical exam demonstrates tachycardia with a systolic murmur heard best along the right upper sternal border. Breath sounds are diminished over the right upper lobe. Bilateral lower extremity pitting edema is noted. Which of the following best describes the most likely diagnosis?", "answer": "Rupture of an emphysematous bleb", "options": {"A": "Fe3+ hemoglobin in circulating red blood cells", "B": "Ischemia of the myocardium", "C": "Pulmonary edema secondary to decreased cardiac output", "D": "Rupture of an emphysematous bleb", "E": "Severe bronchoconstriction"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 38-year-old man presents to the emergency department due to severe alcohol intoxication. The patient is agitated and refuses to answer any questions in regards to his medical history. The vital signs are within normal limits. The complete blood count results demonstrate hemoglobin of 11.5 g/dL, hematocrit of 39%, and mean corpuscular volume of 77 μm3. Using a special dye, the histology demonstrates blue-colored rings in the peripheral smear. What are the most likely findings on the ferritin, total iron-binding capacity, and serum iron levels?", "answer": "Ferritin: ↑, total iron-binding capacity: ↓, serum iron: ↑", "options": {"A": "Ferritin: ↓, total iron-binding capacity: ↓, serum iron: ↓", "B": "Ferritin: normal, total iron binding capacity: normal, serum iron: normal", "C": "Ferritin: ↑, total iron-binding capacity: ↓, serum iron: ↑", "D": "Ferritin: ↑, total iron-binding capacity: ↓, serum iron: ↓", "E": "Ferritin: ↓, total iron-binding capacity: ↑, serum iron: ↓"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to see his pediatrician because of painless swelling in both legs and around his eyes. His mother reports that it is worse in the morning and these symptoms have started 4 days ago. The child has just recovered from a severe upper respiratory tract infection 8 days ago. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Today, his blood pressure is 110/65 mm Hg, the heart rate is 90/min, the respiratory rate is 22/min, and the temperature is 36.8°C (98.2°F). On physical examination, his face is edematous and there is a 2+ pitting edema over both legs up to his hips. Laboratory results are shown.\nSerum albumin 2.4 g/dL\nSerum triglycerides 250 mg/dL\nSerum cholesterol 300 mg/dL\nUrine dipstick 4+ protein\nWhich of the following is the best initial therapy for this patient’s condition?", "answer": "Prednisolone", "options": {"A": "Albumin infusion", "B": "Oral antibiotic", "C": "Enalapril", "D": "Prednisolone and cyclophosphamide", "E": "Prednisolone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old man is brought to the Emergency Department with intense chest pain that radiates to his left arm and jaw. He also complains of feeling lightheaded. Upon arrival, his blood pressure is 104/60 mm Hg, pulse is 102/min, respiratory rate is 25/min, body temperature is 36.5°C (97.7°F), and oxygen saturation is 94% on room air. An electrocardiogram shows an ST-segment elevation in I, aVL, and V5-6. The patient is transferred to the cardiac interventional suite for a percutaneous coronary intervention. The patient is admitted to the hospital after successful revascularization. During his first night on the ICU floor his urinary output is 0.15 mL/kg/h. Urinalysis shows muddy brown casts. Which of the following outcomes specific to the patient’s condition would you expect to find?", "answer": "Blood urea nitrogen (BUN):Serum creatinine ratio (Cr) < 15:1", "options": {"A": "Urinary osmolality 900 mOsmol/kg (normal: 500–800 mOsmol/kg)", "B": "Urinary osmolality 550 mOsmol/kg (normal: 500–800 mOsmol/kg)", "C": "Blood urea nitrogen (BUN):Serum creatinine ratio (Cr) > 20:1", "D": "Blood urea nitrogen (BUN):Serum creatinine ratio (Cr) < 15:1", "E": "FENa+ < 1%"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously-healthy 24-year-old male is admitted to the intensive care unit following a motorcycle crash. He sustained head trauma requiring an emergency craniotomy, has burns over 30% of his body, and a fractured humerus. His pain is managed with a continuous fentanyl infusion. Two days after admission to the ICU he develops severe hematemesis. What is the mechanism underlying the development of his hematemesis?", "answer": "Answers 1 and 2", "options": {"A": "Gastric mucosal disruption", "B": "Increased gastric acid production", "C": "Helicobacter pylori infection", "D": "Answers 1 and 2", "E": "Fentanyl overuse"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-year-old man presents with a sudden loss of consciousness while playing college football. There was no history of a concussion. Echocardiography shows left ventricular hypertrophy and increased thickness of the interventricular septum. Which is the most likely pathology underlying the present condition?", "answer": "Mutation in the myosin heavy chain", "options": {"A": "Streptococcal infection", "B": "Mutation in the myosin heavy chain", "C": "Drug abuse", "D": "Viral infection", "E": "Autoimmunity of myocardial fibers"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 69-year-old man is brought to the emergency department because of severe abdominal pain radiating to his left flank for 30 minutes. He is weak and has been unable to stand since the onset of the pain. He vomited twice on the way to the hospital. He has not passed stools for 3 days. He has hypertension, coronary heart disease, and peptic ulcer disease. He has smoked half a pack of cigarettes daily for 46 years. Current medications include enalapril, metoprolol, aspirin, simvastatin, and pantoprazole. He appears ill. His temperature is 37°C (98.6°F), pulse is 131/min, respirations are 31/min, and blood pressure is 82/56 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 92%. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. Examination shows a painful pulsatile abdominal mass. Intravenous fluid resuscitation is begun. Which of the following is the most appropriate next step in management?", "answer": "Open emergency surgery", "options": {"A": "Supine and erect x-rays of the abdomen", "B": "CT scan of the abdomen and pelvis with contrast", "C": "Open emergency surgery", "D": "Transfusion of packed red blood cells", "E": "Colonoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old man comes to the emergency department with fever, chills, dyspnea, and a productive cough. His symptoms began suddenly 2 days ago. He was diagnosed with HIV 4 years ago and has been on triple antiretroviral therapy since then. He smokes one pack of cigarettes daily. He is 181 cm (5 ft 11 in) tall and weighs 70 kg (154 lb); BMI is 21.4 kg/m2. He lives in Illinois and works as a carpenter. His temperature is 38.8°C (101.8°F), pulse is 110/min, respirations are 24/min, and blood pressure is 105/74 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 92%. Examinations reveals crackles over the right lower lung base. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11.5 g/dL\nLeukocyte count 12,800/mm3\nSegmented neutrophils 80%\nEosinophils 1%\nLymphocytes 17%\nMonocytes 2%\nCD4+ T-lymphocytes 520/mm3(N ≥ 500)\nPlatelet count 258,000/mm3\nSerum\nNa+ 137 mEq/L\nCl- 102 mEq/L\nK+ 5.0 mEq/L\nHCO3- 22 mEq/L\nGlucose 92 mg/dL\nAn x-ray of the chest shows a right lower-lobe infiltrate of the lung. Which of the following is the most likely causal organism?\"", "answer": "Streptococcus pneumoniae", "options": {"A": "Staphylococcus aureus", "B": "Cryptococcus neoformans", "C": "Legionella pneumophila", "D": "Streptococcus pneumoniae", "E": "Pneumocystis jirovecii"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-month-old boy is brought to his pediatrician because his parents have noticed that he has very restricted joint movement. He was born at home without prenatal care, but they say that he appeared healthy at birth. Since then, they say that he doesn't seem to move very much and is hard to arouse. Physical exam reveals coarse facial structures and hepatosplenomegaly. Radiography reveals skeletal malformations, and serum tests show high plasma levels of lysosomal enzymes. The production of which of the following substances will most likely be disrupted in this patient?", "answer": "Mannose-6-phosphate", "options": {"A": "Ceramide", "B": "Glucocerebroside", "C": "GM3", "D": "Heparin sulfate", "E": "Mannose-6-phosphate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old man comes to the physician for a 1-month history of fever, chest pain with deep breathing, and a 4-kg (9 lb) weight loss. His temperature is 38°C (100.4°F). An x-ray of the chest shows a subpleural nodule in the right lower lobe with right hilar lymphadenopathy. Histological examination of a right hilar lymph node biopsy specimen shows several granulomas with acellular cores. Which of the following is the most likely diagnosis?", "answer": "Primary tuberculosis", "options": {"A": "Hodgkin lymphoma", "B": "Primary tuberculosis", "C": "Chronic berylliosis", "D": "Miliary tuberculosis", "E": "Pulmonary sarcoidosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old man presents with breathlessness and altered mental status. The patient’s daughter says that he has been having high fever and cough for the last 3 days. Past medical history is significant for a recent hospitalization 5 days ago, following a successful coronary artery bypass grafting (CABG). In the post-operative period, he was in an intensive care unit (ICU) for 6 days, including 12 hours on mechanical ventilation. Current medications are aspirin and rosuvastatin. The patient’s daughter mentions that he has had anaphylactic reactions to penicillin in the past. His temperature is 39.4°C (103°F), pulse rate is 110/min, blood pressure is 104/78 mm Hg, and respiratory rate is 30/min. On physical examination, the patient is confused and disoriented and shows signs of respiratory distress and cyanosis. On chest auscultation, there is crepitus in the right lung. The patient is immediately started on oxygen therapy, intravenous fluids, and supportive care. After the collection of appropriate samples for bacteriological culture, treatment with empirical intravenous antibiotics are started. After 24 hours of treatment, the microbiology results indicate Pseudomonas aeruginosa infection. Antibiotic therapy is changed to a combination of aztreonam and tobramycin. Which of the following best describes the rationale for choosing this antibiotic combination?", "answer": "Synergism of aztreonam with tobramycin", "options": {"A": "Broad-spectrum coverage against gram-positive cocci by adding tobramycin to aztreonam", "B": "Effective combination of a bactericidal and a bacteriostatic antimicrobial against Pseudomonas aeruginosa", "C": "Reduction of the side-effects of both aztreonam and tobramycin", "D": "Synergism of aztreonam with tobramycin", "E": "Broad-spectrum coverage against anaerobes by adding tobramycin to aztreonam"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 9-year-old girl is brought to the emergency department with a headache and double vision 1 hour after being hit on the head while playing with a friend. Her friend's elbow struck her head, just above her left ear. She did not lose consciousness, but her mother reports that she was confused for 20 minutes after the incident and did not recall being hit. She appears healthy. She is alert and oriented to person, place, and time. Her temperature is 37.2°C (99°F), pulse is 86/min, respirations are 15/min, and blood pressure is 118/78 mmHg. Examination shows the head tilted toward the right shoulder. A photograph of the eyes at primary gaze is shown. There is mild tenderness to palpation over the left temporal bone. Visual acuity is 20/20 in both eyes when tested independently. The patient's left eye hypertropia worsens with right gaze and when the patient tilts her head toward her left shoulder. The pupils are equal and reactive to light. Muscle strength and sensation are intact bilaterally. Deep tendon reflexes are 2+ bilaterally. Plantar reflex shows a flexor response. Which of the following is the most likely cause of this patient's ocular symptoms?", "answer": "Trochlear nerve damage", "options": {"A": "Oculomotor nerve damage", "B": "Retrobulbar hemorrhage", "C": "Trochlear nerve damage", "D": "Medial longitudinal fasciculus damage", "E": "Dorsal midbrain damage"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 8-year-old girl is brought to the emergency department by her parents with severe difficulty in breathing for an hour. She is struggling to breathe. She was playing outside with her friends, when she suddenly fell to the ground, out of breath. She was diagnosed with asthma one year before and has since been on treatment for it. At present, she is sitting leaning forward with severe retractions of the intercostal muscles. She is unable to lie down. Her parents mentioned that she has already taken several puffs of her inhaler since this episode began but without response. On physical examination, her lungs are hyperresonant to percussion and there is decreased air entry in both of her lungs. Her vital signs show: blood pressure 110/60 mm Hg, pulse 110/min, respirations 22/min, and a peak exploratory flow rate (PEFR) of 50%. She is having difficulty in communicating with the physician. Her blood is sent for evaluation and a chest X-ray is ordered. Her arterial blood gas reports are as follows:\nPaO2 50 mm Hg\npH 7.38\nPaCO2 47 mm Hg\nHCO3 27 mEq/L\nWhich of the following is the most appropriate next step in management?", "answer": "Mechanical ventilation", "options": {"A": "Methacholine challenge test", "B": "Inhaled β-agonist", "C": "Inhaled corticosteroid", "D": "Intravenous corticosteroid", "E": "Mechanical ventilation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 12-hour-old newborn is found to have difficulty breathing and bluish skin appearance by the shift nurse. The birth was unremarkable and the mother is known to be diabetic. The child is examined by the on-call physician, who detects a single loud S2. The chest X-ray shows an 'egg-shaped' heart. Which medication below would possibly prevent further progression of the patient’s symptoms?", "answer": "Prostaglandins E2", "options": {"A": "Indomethacin", "B": "Low-dose aspirin", "C": "Prostaglandins E2", "D": "Erythromycin ointment", "E": "Vitamin K"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old woman was recently diagnosed with pancreatic cancer. At what point should her physician initiate a discussion with her regarding advance directive planning?", "answer": "At this visit", "options": {"A": "Now that she is ill, speaking about advanced directives is no longer an option", "B": "At this visit", "C": "Only if her curative surgical and medical treatment fails", "D": "Once she enters hospice", "E": "Only if she initiates the conversation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 38-year-old woman comes to the physician for a follow-up visit. She has a 2-year history of depressed mood and fatigue accompanied by early morning awakening. One week ago, she started feeling a decrease in her need for sleep and now feels rested after about 5 hours of sleep per night. She had two similar episodes that occurred 6 months ago and a year ago, respectively. She reports increased energy and libido. She has a 4-kg (8.8-lb) weight loss over the past month. She does not feel the need to eat and says she derives her energy \"\"from the universe\"\". She enjoys her work as a librarian. She started taking fluoxetine 3 months ago. On mental exam, she is alert and oriented to time and place; she is irritable. She does not have auditory or visual hallucinations. Physical examination shows no abnormalities. Which of the following is the most likely diagnosis?\"", "answer": "Cyclothymic disorder\n\"", "options": {"A": "Medication-induced bipolar disorder", "B": "Bipolar disorder with rapid cycling", "C": "Delusional disorder", "D": "Schizoaffective disorder", "E": "Cyclothymic disorder\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 33-year-old man presents to his primary care physician with shoulder pain. He states that he can't remember a specific instance when the injury occurred. He is a weight lifter and competes in martial arts. The patient has no past medical history and is currently taking a multivitamin. Physical exam demonstrates pain with abduction of the patient's right shoulder and with external rotation of the right arm. There is subacromial tenderness with palpation. His left arm demonstrates 10/10 strength with abduction as compared to 4/10 strength with abduction of the right arm. Which of the following best confirms the underlying diagnosis?", "answer": "MRI", "options": {"A": "CT", "B": "MRI", "C": "Physical exam and history", "D": "Radiography", "E": "Ultrasound"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-year-old boy comes to the physician because of a 4-month history of intermittent red urine. During the past 2 years, he has had recurrent episodes of swelling of his face and feet. Five years ago, he was diagnosed with mild bilateral sensorineural hearing loss. His uncle died of kidney disease in his twenties. His blood pressure is 145/85 mm Hg. Laboratory studies show a hemoglobin concentration of 12.5 g/dL, urea nitrogen concentration of 40 mg/dL, and creatinine concentration of 2.4 mg/dL. Urinalysis shows 5–7 RBC/hpf. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Defective type IV collagen", "options": {"A": "Defective type IV collagen", "B": "Autosomal-recessive gene defect in fibrocystin", "C": "Phospholipase A2 receptor antibody", "D": "Prior streptococcal infection", "E": "Vascular IgA deposits"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old man with a history of epilepsy comes to the physician for a follow-up examination. He has had trouble moving the right side of his body for 2 weeks. Three weeks ago he was admitted to the hospital for a generalized convulsive seizure. He was treated with intravenous lorazepam and phenytoin; the seizure activity resolved after 50 minutes on EEG monitoring. He was discharged 2 days later after no further epileptic activity occurred. Physical examination at discharge showed no abnormalities. He has had multiple hospitalizations for similar episodes over the past year. His only medication is lamotrigine, though he says that he sometimes forgets to take it. His temperature is 37°C (98.6°F), pulse is 70/min, and blood pressure is 130/80 mm Hg. Physical examination shows right-sided hemiparesis, right homonymous hemianopsia, and receptive aphasia. Which of the following is the most likely underlying cause of this patient's current symptoms?", "answer": "Cortical laminar necrosis", "options": {"A": "Lacunar stroke", "B": "Brain abscess", "C": "Cortical laminar necrosis", "D": "Intraventricular hemorrhage", "E": "Ruptured intracranial aneurysm"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old patient presents to the hospital complaining of progressively worsening dyspnea and a dry cough. Radiographic imaging is shown below. Pulmonary function testing (PFT's) reveals a decreased FEV1 and FEV1/FVC, but an increase TLC. The patient states that he does not smoke. Which of the following conditions is most consistent with the patients symptoms?", "answer": "Alpha1-antitrypsin deficiency", "options": {"A": "Chronic bronchitis", "B": "Alpha1-antitrypsin deficiency", "C": "Pneumothorax", "D": "Asthma", "E": "Hypersensitivity pneumonitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man presents to the clinic with a complaint of lightheadedness when standing up from his bed in the morning and then from his chair at work. He has had similar complaints for many months, and the symptoms have not improved despite drinking lots of fluids, eating regular meals, and taking daily multivitamin. His daily routine is disturbed as he finds himself getting up very slowly to avoid the problem. This has created some awkward situations at his workplace and in social settings. His blood pressure while seated is 120/80 mm Hg, and upon standing it falls to 100/68 mm Hg. The physical examination is unremarkable except for a strong odor suggestive of marijuana use. The patient denies drug use and insists the odor is due to his roommate who smokes marijuana for medical purposes. No pallor or signs of dehydration are seen. The lab results are as follows:\nSerum Glucose 90 mg/dL\nSodium 140 mEq/L\nPotassium 4.1 mEq/L\nChloride 100 mEq/L\nSerum Creatinine 0.8 mg/dL\nBlood Urea Nitrogen 9 mg/dL\nHemoglobin (Hb) Concentration 15.3 g/dL\nMean Corpuscular Volume (MCV) 83 fl\nReticulocyte count 0.5%\nErythrocyte count 5.3 million/mm3\nPlatelet count 200,000/mm3\nThe ECG shows no abnormal finding. Which of the following could alleviate this patient’s symptoms?", "answer": "Alpha 1 receptor activation", "options": {"A": "Alpha 1 receptor activation", "B": "Carotid massage", "C": "Increased parasympathetic stimulation", "D": "Inhibition of the baroreceptor response", "E": "Sodium chloride infusion"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old girl is brought to the clinic for evaluation of malaise and low-grade fever over the past 3 days. In the last 24 hours, she developed sores and pain in her mouth. She also had vesicles on her hands and feet. Her past medical history was benign and the immunization history was up-to-date. The oral temperature was 36.1°C (97.0°F). The physical examination revealed several erythematous macules in the oropharynx and small oval vesicles with an erythematous base on the palms. What is the next best step in the management of this patient?", "answer": "Supportive care", "options": {"A": "Ribavirin", "B": "Supportive care", "C": "Aspirin", "D": "Corticosteroids", "E": "Penicillin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 37-year-old woman presents with a 3-day history of fever. Past medical history is significant for chronic schizophrenia, managed with an antipsychotic medication. The patient has a low-grade fever and is slightly tachycardic. Physical examination is significant for the presence of tonsillar exudates. A CBC shows a markedly decreased WBC count. The patient’s antipsychotic medication is immediately discontinued. Which of the following is the antipsychotic medication that could have caused this problem?", "answer": "Clozapine", "options": {"A": "Quetiapine", "B": "Olanzapine", "C": "Risperidone", "D": "Clozapine", "E": "Haloperidol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 61-year-old man is brought to the emergency department because of increasing weakness of his right arm and leg that began when he woke up that morning. He did not notice any weakness when he went to bed the night before. He has hypertension and hypercholesterolemia. Current medications include hydrochlorothiazide and atorvastatin. He is alert and oriented to person, time, place. His temperature is 36.7°C (98°F), pulse is 91/min, and blood pressure is 132/84 mm Hg. Examination shows drooping of the right side of the face. Muscle strength is decreased in the right upper and lower extremities. Deep tendon reflexes are 4+ on the right side. Sensation is intact. His speech is normal in rate and rhythm. The remainder of the examination shows no abnormalities. An infarction of which of the following sites is the most likely cause of this patient's symptoms?", "answer": "Posterior limb of the left internal capsule", "options": {"A": "Posterior limb of the left internal capsule", "B": "Base of the left pons", "C": "Left posterolateral thalamus", "D": "Left lateral medulla", "E": "Left cerebellar vermis\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old woman comes to the physician because of a 1-month history of persistent epigastric abdominal pain. She reports dull, aching pain that is worse after meals and wakes her up at night. She is afraid to eat, as it worsens the pain, and has had a 2-kg (4.4-lb) weight loss during this time. She has smoked a pack of cigarettes daily for the past 40 years. Her only medication is a calcium supplement. Her vital signs are within normal limits. She appears thin. Examination shows yellow discoloration of the sclera. The remainder of the examination shows no abnormalities. Laboratory studies show a total bilirubin of 9.8 mg/dL, direct bilirubin of 8.6 mg/dL, and an alkaline phosphatase of 120 IU/L. Abdominal ultrasonography shows dilation of the biliary and pancreatic ducts but no pancreatic or extrahepatic biliary lesions. Which of the following is the most appropriate next step in management?", "answer": "Contrast-enhanced abdominal CT", "options": {"A": "Colonoscopy", "B": "Plain abdominal CT", "C": "Contrast-enhanced abdominal CT", "D": "Endoscopic ultrasonography", "E": "Endoscopic retrograde cholangiopancreatography"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 73-year-old male presents to the ED with several days of fevers, cough productive of mucopurulent sputum, and pleuritic chest pain. He has not been to a doctor in 30 years because he “has never been sick”. His vital signs are: T 101F, HR 98, BP 100/55, RR 31. On physical exam he is confused and has decreased breath sounds and crackles on the lower left lobe. Gram positive diplococci are seen in the sputum. Which of the following is the most appropriate management for his pneumonia?", "answer": "IV Penicillin G and inpatient admission", "options": {"A": "Oral Penicillin V and outpatient follow-up", "B": "IV Penicillin G and inpatient admission", "C": "Azithromycin and outpatient follow-up", "D": "Linezolid and inpatient admission", "E": "Levofloxacin and outpatient follow-up"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 48-year-old male accountant presents to the family practice clinic for his first health check-up in years. He has no complaints, and as far as he is concerned, he is well. He does not have any known medical conditions. With respect to the family history, the patient reports that his wife's brother died of a heart attack at 35 years of age. His blood pressure is 140/89 mm Hg and his heart rate is 89/min. Physical examination is otherwise unremarkable. What is the single best initial management for this patient?", "answer": "Return to the clinic for a repeat blood pressure reading and counseling on the importance of aerobic exercise.", "options": {"A": "Return to the clinic for a repeat blood pressure reading and counseling on the importance of aerobic exercise.", "B": "Try angiotensin-converting enzyme inhibitor.", "C": "Start trial of calcium channel blockers.", "D": "Treat the patient with beta-blockers.", "E": "The patient does not require any treatment."}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old man, an information technology professional, gets himself tested for serum immunoglobulin M (IgM) levels because he wants to know more about his immunity. He knows that IgM levels reflect the status of his immunity, based on the internet. Although the laboratory report is normal, he consults a physician. The physician discusses human immunity and its important components. He also tells him that most circulating IgM antibodies in the blood of normal persons are produced by a specific type of B cell, which is present mostly in the peritoneal cavity and in mucosal tissues. He also mentions that these cells are components of innate immunity. Which of the following types of B cells is the physician referring to?", "answer": "B-1 B cells", "options": {"A": "B-1 B cells", "B": "Follicular B cells", "C": "Marginal zone B cells", "D": "Memory B cells", "E": "Naïve B cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 37-year-old man presents to his gastroenterologist due to a transaminitis found by his primary care physician (PCP). He reports currently feeling well and has no acute concerns. Medical history is significant for ulcerative colitis treated with 5-aminosalicylate. He recently went on a trip to Mexico and experienced an episode of mild diarrhea. The patient is 5 ft 4 in and weighs 220 lbs (99.8 kg). His temperature is 98°F (36.7°C), blood pressure is 138/88 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination is unremarkable. Laboratory testing demonstrates:\n\nLeukocyte count: 7,200 /mm^3\nAlkaline phosphatase: 205 U/L\nAspartate aminotransferase (AST): 120 U/L\nAlanine aminotransferase (ALT): 115 U/L\nPerinuclear antineutrophil cytoplasmic antibody (pANCA): Positive\nAntimitochondrial antibody: Negative\n\nWhich of the following is most likely the diagnosis?", "answer": "Primary sclerosing cholangitis", "options": {"A": "Acute cholecystitis", "B": "Acute viral hepatitis", "C": "Choledocholithiasis", "D": "Primary biliary cirrhosis", "E": "Primary sclerosing cholangitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old man comes to the emergency department because of a pounding headache for the past 3 hours. The pain is 8 out of 10 in intensity, does not radiate, and is not relieved by ibuprofen. He also has associated dizziness, blurring of vision, and palpitations. He has had similar episodes over the last 6 months but none this severe. He has not had fever, weight change, or loss of appetite. He underwent an appendectomy at the age of 18. His father died of renal cancer. He is diaphoretic. His temperature is 36.8°C (98.4°F), pulse is 112/min, and blood pressure is 220/130 mm Hg. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14.8 g/dL\nLeukocyte count 9600/mm3\nPlatelet count 345,000/mm3\nSerum\nGlucose 112 mg/dL\nNa+ 137 mEq/L\nK+ 4.2 mEq/L\nCl- 105 mEq/L\nCreatinine 1.0 mg/dL\nUrine dipstick shows no abnormalities. Which of the following findings on imaging is the most likely explanation for this patient's symptoms?\"", "answer": "Adrenal medullary mass", "options": {"A": "Paravertebral mass", "B": "Meningeal mass", "C": "Adrenal medullary mass", "D": "Renal cortical mass", "E": "Intracranial hemorrhage"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 65-year-old male with multiple comorbidities presents to your office complaining of difficulty falling asleep. Specifically, he says he has been having trouble breathing while lying flat very shortly after going to bed. He notes it only gets better when he adds several pillows, but that sitting up straight is an uncomfortable position for him in which to fall asleep. What is the most likely etiology of this man's sleeping troubles?", "answer": "Left-sided heart failure", "options": {"A": "Obstructive sleep apnea", "B": "Amyotrophic lateral sclerosis (ALS)", "C": "Myasthenia gravis", "D": "Right-sided heart failure", "E": "Left-sided heart failure"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 2-month-old girl is brought to the emergency department because her lips turned blue while passing stools 30 minutes ago. She is at the 40th percentile for length and below the 35th percentile for weight. Pulse oximetry on room air shows an oxygen saturation of 65%, which increases to 76% on administration of 100% oxygen. Physical examination shows perioral cyanosis and retractions of the lower ribs with respiration. Cardiac examination shows a harsh grade 2/6 systolic crescendo-decrescendo murmur heard best at the left upper sternal border. Which of the following is most likely to improve this patient's symptoms?", "answer": "Knee to chest positioning", "options": {"A": "Cooling of the face", "B": "Elevation of the lower extremities", "C": "Administration of indomethacin", "D": "Hyperextension of the neck", "E": "Knee to chest positioning"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A newborn male is evaluated in the hospital nursery two hours after birth. The patient was born at 39 weeks of gestation to a 30-year-old primigravid via vaginal delivery. The patient’s mother received routine prenatal care, and the pregnancy was uncomplicated. The patient’s anatomy ultrasound at 20 weeks of gestation was unremarkable. The patient’s mother denies any family history of genetic diseases. The patient’s Apgar scores were notable for poor muscle tone at both one and five minutes of life. The patient’s birth weight is 2.6 kg (5 lb 11 oz), which is at the 5th percentile. His height and head circumference are in the 15th and 3rd percentile, respectively. On physical exam, the patient has a wide nasal bridge, downslanting palpebral fissures, and widely spaced eyes. He has good respiratory effort with a high-pitched cry. This patient is most likely to have experienced a deletion on which of the following chromosomes?", "answer": "5p", "options": {"A": "4p", "B": "5p", "C": "5q", "D": "7q", "E": "15q"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 44-year-old male presents to his primary care physician with complaints of fatigue, muscle weakness, cramps, and increased urination over the past several weeks. His past medical history is significant only for hypertension, for which he was started on hydrochlorothiazide (HCTZ) 4 weeks ago. Vital signs at today's visit are as follows: T 37.2, HR 88, BP 129/80, RR 14, and SpO2 99%. Physical examination does not reveal any abnormal findings. Serologic studies are significant for a serum potassium level of 2.1 mEq/L (normal range 3.5-5.0 mEq/L). Lab-work from his last visit showed a basic metabolic panel and complete blood count results to all be within normal limits. Which of the following underlying diseases most likely contributed to the development of this patient's presenting condition?", "answer": "Hyperaldosteronism", "options": {"A": "Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH)", "B": "Pituitary adenoma", "C": "Adrenal insufficiency", "D": "Hyperaldosteronism", "E": "Cushing's disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old man presents the emergency department for intense chest pain, profuse sweating, and shortness of breath. The onset of these symptoms was 3 hours ago. The chest pain began after a heated discussion with a colleague at the community college where he is employed. Upon arrival, he is found conscious and responsive; the vital signs include a blood pressure of 130/80 mm Hg, a heart rate at 90/min, a respiratory rate at 20/min, and a body temperature of 36.4°C (97.5°F). His medical history is significant for hypertension diagnosed 7 years ago, which is well-controlled with a calcium channel blocker. The initial electrocardiogram (ECG) shows ST-segment depression in multiple consecutive leads, an elevated cardiac troponin T level, and normal kidney function. Which of the following would you expect to find in this patient?", "answer": "Subendocardial necrosis", "options": {"A": "Ventricular pseudoaneurysm", "B": "Transmural necrosis", "C": "Subendocardial necrosis", "D": "Incomplete occlusion of a coronary artery", "E": "Coronary artery spasm"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "The patient is admitted to the hospital. A stereotactic brain biopsy of the suspicious lesion is performed that shows many large lymphocytes with irregular nuclei. Which of the following is the most appropriate treatment?", "answer": "Methotrexate", "options": {"A": "Intrathecal glucocorticoids", "B": "Temozolomide", "C": "Pyrimethamine and sulfadiazine", "D": "Methotrexate", "E": "Surgical resection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "You are counseling a mother whose newborn has just screened positive for a deficit of phenylalanine hydroxylase enzyme. You inform her that her child will require dietary supplementation of which of the following?", "answer": "Tyrosine", "options": {"A": "Leucine", "B": "Aspartame", "C": "Tyrosine", "D": "Niacin", "E": "Homogentisic Acid"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old male is brought to the physician by his wife who is concerned because he has begun to demonstrate odd behavior which has worsened over the past several months. She states that he has become very aggressive and at times will have sudden, jerky movements which he is unable to control. The patient states that his father had the same problem which he died of at age 69. The patient had a recent, \"cold,\" with fevers, chills and, \"throat pain,\" which resolved on its own, \"some time ago.\" Which of the following is true of this disease?", "answer": "It demonstrates anticipation", "options": {"A": "A mutation in ATP7B on chromosome 13 is responsible", "B": "Erythema marginatum is a complication associated with this disease", "C": "Overactivity of dopamine in the mesolimbic pathway is the underlying pathology", "D": "Underactivity of dopamine in the nigrostriatal cortex is the underlying pathology", "E": "It demonstrates anticipation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old male with no significant medical history comes to you with a urine positive for fructose. He does not have diabetes mellitus. Which enzyme is most likely to be deficient in this patient?", "answer": "Fructokinase", "options": {"A": "Aldolase B", "B": "Galactokinase", "C": "Fructokinase", "D": "Pyruvate kinase", "E": "Lactase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old male presents after several days of flatulence and greasy, foul-smelling diarrhea. The patient reports symptoms of nausea and abdominal cramps followed by sudden diarrhea. He says that his symptoms started after he came back from a camping trip. When asked about his camping activities, he reports that his friend collected water from a stream, but he did not boil or chemically treat the water. His temperature is 98.6°F (37°C), respiratory rate is 15/min, pulse is 67/min, and blood pressure is 122/98 mm Hg. Stool is sent for microscopy which returns positive for motile protozoans. Which of the following antibiotics should be started in this patient?", "answer": "Metronidazole", "options": {"A": "Erythromycin", "B": "Ciprofloxacin", "C": "Metronidazole", "D": "Vancomycin", "E": "Cephalexin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old man comes to the physician for a 5-month history of hoarseness, exertional dyspnea, and fatigue. He does not smoke or drink alcohol. His pulse is 98/min and irregular. His voice is coarse in quality. Physical examination shows a liver span of 16 cm and a soft diastolic murmur heard best at the apex. Which of the following is the most likely cause of this patient's hoarseness?", "answer": "Extrinsic impingement of the recurrent laryngeal nerve", "options": {"A": "Carcinoma arising from the mucosa of the larynx", "B": "Extrinsic impingement of the recurrent laryngeal nerve", "C": "Bacterial infection of the vocal folds", "D": "Laryngeal inflammation due to chemical irritant", "E": "Circulating acetylcholine receptor antibodies\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old girl is brought to the physician by her mother for a well-child examination. Cardiac auscultation is shown. When she clenches her fist forcefully for a sustained time, the intensity of the murmur increases. Which of the following is the most likely cause of this patient's auscultation findings?", "answer": "Defect in the ventricular septum", "options": {"A": "Prolapse of the mitral valve", "B": "Fusion of the right and left coronary leaflets", "C": "Defect in the atrial septum", "D": "Defect in the ventricular septum", "E": "Failure of the ductus arteriosus to close"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old woman comes to the physician because she has not had her menstrual period for the past 4 months. During this period, she has had frequent headaches, difficulty sleeping, and increased sweating. She has not had any weight changes. Over the past year, menses occurred at irregular 30- to 45-day intervals with light flow. The patient underwent two successful cesarean sections at the ages of 28 and 32. She has two healthy children. She is sexually active with her husband and does not use condoms. Her vital signs are within normal limits. Physical examination shows no abnormalities. Laboratory studies show:\nEstradiol 8 pg/mL (mid-follicular phase: N=27–123 pg/mL)\nFollicle-stimulating hormone 200 mIU/mL\nLuteinizing hormone 180 mIU/mL\nProlactin 16 ng/mL\nWhich of the following is the most likely diagnosis?\"", "answer": "Premature ovarian failure", "options": {"A": "Primary hypothyroidism", "B": "Pregnancy", "C": "Premature ovarian failure", "D": "Polycystic ovary syndrome", "E": "Major depressive disorder"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 63-year-old man comes to the physician for blurry vision and increased difficulty walking over the past month. He feels very fatigued after watering his garden but feels better after taking a nap. He has not had any recent illness. He has smoked one pack of cigarettes daily for 35 years. Examination shows drooping of the upper eyelids bilaterally and diminished motor strength in the upper extremities. Sensation to light touch and deep tendon reflexes are intact. An x-ray of the chest shows low lung volumes bilaterally. A drug with which of the following mechanisms of action is most appropriate for this patient?", "answer": "Inhibition of acetylcholinesterase", "options": {"A": "Inhibition of muscarinic ACh receptor", "B": "Regeneration of acetylcholinesterase", "C": "Stimulation of D2 receptors", "D": "Stimulation of β2 adrenergic receptors", "E": "Inhibition of acetylcholinesterase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 82-year-old woman is brought to the physician by her daughter because of a 3-day history of a runny nose, headache, and cough. The patient's grandson recently had similar symptoms. Her vital signs are within normal limits. Pulse oximetry on room air shows an oxygen saturation of 99%. Lungs are clear to auscultation. Testing of nasal secretions is performed to identify the viral strain. Electron microscopy shows a non-enveloped RNA virus with an icosahedral capsid. Binding to which of the following is responsible for the virulence of this virus?", "answer": "ICAM-1", "options": {"A": "P antigen", "B": "CD21", "C": "ICAM-1", "D": "Sialic acid residues", "E": "Integrin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 31-year-old man presents to the Emergency Department with severe left leg pain and paresthesias 4 hours after his leg got trapped by the closing door of a bus. Initially, he had a mild pain which gradually increased to unbearable levels. Past medical history is noncontributory. In the Emergency Department, his blood pressure is 130/80 mm Hg, heart rate is 87/min, respiratory rate is 14/min, and temperature is 36.8℃ (98.2℉). On physical exam, his left calf is firm and severely tender on palpation. The patient cannot actively dorsiflex his left foot, and passive dorsiflexion is limited. Posterior tibial and dorsalis pedis pulses are 2+ in the right leg and 1+ in the left leg. Axial load does not increase the pain. Which of the following is the best next step in the management of this patient?", "answer": "Fasciotomy", "options": {"A": "Lower limb CT scan", "B": "Lower limb X-ray in two projections", "C": "Lower limb ultrasound", "D": "Splinting and limb rest", "E": "Fasciotomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old G2P0A2 woman comes to the office complaining of light vaginal spotting. She received a suction curettage 2 weeks ago for an empty gestational sac. Pathology reports showed hyperplastic and hydropic trophoblastic villi, but no fetal tissue. The patient denies fever, abdominal pain, dysuria, dyspareunia, or abnormal vaginal discharge. She has no chronic medical conditions. Her periods are normally regular and last 3-4 days. One year ago, she had an ectopic pregnancy that was treated with methotrexate. She has a history of chlamydia and gonorrhea that was treated 5 years ago with azithromycin and ceftriaxone. Her temperature is 98°F (36.7°C), blood pressure is 125/71 mmHg, and pulse is 82/min. On examination, hair is present on the upper lip, chin, and forearms. A pelvic examination reveals a non-tender, 6-week-sized uterus and bilateral adnexal masses. There is scant dark blood in the vaginal vault on speculum exam. A quantitative beta-hCG is 101,005 mIU/mL. Two weeks ago, her beta-hCG was 63,200 mIU/mL. A pelvic ultrasound shows bilaterally enlarged ovaries with multiple thin-walled cysts between 2-3 cm in size. Which of the following is the most likely cause of the patient’s adnexal masses?", "answer": "Theca lutein cysts", "options": {"A": "Corpus luteal cysts", "B": "Dermoid cysts", "C": "Ectopic pregnancy", "D": "Endometrioma", "E": "Theca lutein cysts"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 78-year-old man is brought to the emergency department because of difficulty speaking. The symptoms began abruptly one hour ago while he was having breakfast with his wife. He has hypertension, type 2 diabetes mellitus, and coronary artery disease. Current medications include pravastatin, lisinopril, metformin, and aspirin. His temperature is 37°C (98.6°F), pulse is 76/min, and blood pressure is 165/90 mm Hg. He is right-handed. The patient speaks in short, simple sentences, and has difficulty repeating sequences of words. He can follow simple instructions. Right facial droop is present. Muscle strength is 4/5 on the right side and 5/5 on the left, and there is a mild right-sided pronator drift. Which of the following is the most likely cause of the patient's symptoms?", "answer": "Occlusion of the left middle cerebral artery", "options": {"A": "Occlusion of the right penetrating arteries", "B": "Occlusion of the right middle cerebral artery", "C": "Occlusion of the left middle cerebral artery", "D": "Occlusion of the right posterior inferior cerebellar artery", "E": "Rupture of left posterior cerebral artery malformation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old man presents for an annual check-up. He is a bodybuilder and tells you he is on a protein-rich diet that only allows for minimal carbohydrate intake. His friend suggests he try exogenous glucagon to help him lose some excess weight before an upcoming competition. Which of the following effects of glucagon is he attempting to exploit?", "answer": "Increased lipolysis in adipose tissues", "options": {"A": "Increased hepatic gluconeogenesis", "B": "Increased hepatic glycogenolysis", "C": "Increased glucose utilization by tissues", "D": "Decreased blood cholesterol level", "E": "Increased lipolysis in adipose tissues"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 18-month-old boy presents to the emergency department for malaise. The boy’s parents report worsening fatigue for 3 days with associated irritability and anorexia. The patient’s newborn screening revealed a point mutation in the beta-globin gene but the patient has otherwise been healthy since birth. On physical exam, his temperature is 102.4°F (39.1°C), blood pressure is 78/42 mmHg, pulse is 124/min, and respirations are 32/min. The child is tired-appearing and difficult to soothe. Laboratory testing is performed and reveals the following:\n\nSerum:\nNa+: 137 mEq/L\nCl-: 100 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 24 mEq/L\nUrea nitrogen: 16 mg/dL\nCreatinine: 0.9 mg/dL\nGlucose: 96 mg/dL\n\nLeukocyte count: 19,300/mm^3 with normal differential\nHemoglobin: 7.8 g/dL\nHematocrit: 21%\nMean corpuscular volume: 82 um^3\nPlatelet count: 324,000/mm^3\nReticulocyte index: 3.6%\n\nWhich of the following is the most likely causative organism for this patient's presentation?", "answer": "Streptococcus pneumoniae", "options": {"A": "Haemophilus influenzae", "B": "Listeria monocytogenes", "C": "Neisseria meningitidis", "D": "Salmonella", "E": "Streptococcus pneumoniae"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-day-old newborn boy has failed to pass meconium after 48 hours. There is an absence of stool in the rectal vault. Family history is significant for MEN2A syndrome. Which of the following confirms the diagnosis?", "answer": "Absence of ganglion cells demonstrated by rectal suction biopsy", "options": {"A": "Absence of ganglion cells demonstrated by rectal suction biopsy", "B": "Atrophic nerve fibers and decreased acetylcholinesterase activity", "C": "Barium enema demonstrating absence of a transition zone", "D": "Rectal manometry demonstrating relaxation of the internal anal sphincter with distension of the rectum", "E": "Genetic testing confirming mutation in the RET oncogene"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 50-year-old man presents to the emergency department with pain and swelling of his right leg for the past 2 days. Three days ago he collapsed on his leg after tripping on a rug. It was a hard fall and left him with bruising of his leg. Since then the pain and swelling of his leg have been gradually increasing. Past medical history is noncontributory. He lives a rather sedentary life and smokes two packs of cigarettes per day. The vital signs include heart rate 98/min, respiratory rate 15/min, temperature 37.8°C (100.1°F), and blood pressure 100/60 mm Hg. On physical examination, his right leg is visibly swollen up to the mid-calf with pitting edema and moderate erythema. Peripheral pulses in the right leg are weak and the leg is tender. Manipulation of the right leg is negative for Homan’s sign. What is the next best step in the management of this patient?", "answer": "Perform a venous ultrasound", "options": {"A": "Make a diagnosis of deep vein thrombosis based on history and physical", "B": "Perform a venous ultrasound", "C": "Start intravenous heparin therapy immediately", "D": "Send the patient to surgery for an emergency fasciotomy", "E": "Perform intravenous venography within 24 hours"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old man comes to the clinic complaining of a persistent cough for the last few months. His cough started gradually about a year ago, and it became more severe and persistent despite all his attempts to alleviate it. During the past year, he also noticed some weight loss and a decrease in his appetite. He also complains of progressive shortness of breath. He has a 40-pack-year smoking history but is a nonalcoholic. Physical examination findings are within normal limits. His chest X-ray shows a mass in the right lung. A chest CT shows a 5 cm mass with irregular borders near the lung hilum. A CT guided biopsy is planned. During the procedure, just after insertion of the needle, the patient starts to feel pain in his right shoulder. Which of the following nerves is responsible for his shoulder pain?", "answer": "Phrenic nerve", "options": {"A": "Intercostal nerves", "B": "Vagus nerve", "C": "Phrenic nerve", "D": "Pulmonary plexus", "E": "Thoracic spinal nerves"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman comes to the emergency department one hour after the sudden onset of diffuse abdominal pain and nausea. She has no history of serious illness. Menses occur at regular 27-day intervals and last 4 to 6 days with moderate flow. Her last menstrual period was 6 weeks ago. She is sexually active with two sexual partners and uses oral contraceptive pills inconsistently. She appears pale and diaphoretic. Her temperature is 37.7°C (99.9°F), pulse is 120/min, respirations are 20/min, and blood pressure is 85/70 mm Hg. Abdominal examination shows diffuse abdominal tenderness. Pelvic examination shows a normal appearing vagina, cervix, and uterus, with right adnexal tenderness. Her hemoglobin concentration is 13 g/dL, leukocyte count is 10,000/mm3, and platelet count is 350,000/mm3. Results of a pregnancy test are pending. Which of the following is the most appropriate next step in management?", "answer": "Administer intravenous normal saline fluids", "options": {"A": "Perform exploratory laparoscopy", "B": "Administer intravenous normal saline fluids", "C": "Perform CT scan of the abdomen and pelvis with contrast", "D": "Transfuse O negative packed red blood cells", "E": "Perform pelvic ultrasound"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An otherwise healthy 15-year-old girl is brought to the physician for evaluation of severe acne that involves her face, chest, and back. It has not improved with her current combination therapy of oral cephalexin and topical benzoyl peroxide. She is sexually active with one male partner, and they use condoms consistently. Facial scarring and numerous comedones are present, with sebaceous skin lesions on her face, chest, and back. Which of the following is indicated prior to initiating the appropriate treatment in this patient?", "answer": "Perform quantitative beta-hCG assay", "options": {"A": "Perform quantitative beta-hCG assay", "B": "Switch cephalexin to doxycycline", "C": "Evaluate color vision", "D": "Administer oral contraceptives", "E": "Measure serum DHEA-S and testosterone levels"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 76-year-old female is brought to the emergency department after being found unresponsive in her room at her nursing facility. Past medical history is significant for Alzheimer's disease, hypertension, and diabetes. Surgical history is notable for an open cholecystectomy at age 38 and multiple cesarean sections. On arrival, she is non-responsive but breathing by herself, and her vital signs are T 102.9 F, HR 123 bpm, BP 95/64, RR 26/min, and SaO2 97% on 6L nasal cannula. On physical exam the patient has marked abdominal distension and is tympanic to percussion. Laboratory studies are notable for a lactic acidosis. An upright abdominal radiograph and CT abdomen/pelvis with contrast are shown in Figures A and B respectively. She is started on IV fluids and a nasogastric tube is placed to suction which returns green bilious fluid. Repeat vitals 1 hour later are T 101F, HR 140 bpm, BP 75/44, RR 30/min, and SaO2 is 100% on the ventilator after she is intubated for airway concerns. What is the next best step in management?", "answer": "Immediate laparotomy and surgical management", "options": {"A": "Therapy with levofloxacin and metronidazole", "B": "Immediate laparotomy and surgical management", "C": "Continue IV fluid hydration, nasogastric suction, NPO", "D": "Pneumatic enema", "E": "Sigmoidoscopy, attempted derotation and rectal tube placement"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old woman, gravida 4, para 3, comes to the physician because of left ankle swelling for 2 months. She notes that the swelling is present throughout the day and decreases when she goes to sleep. One year ago, she has had an episode of deep venous thrombosis after the delivery of her third child. Her prepregnancy BMI was 34 kg/m2. Examination shows distended, tortuous veins in the legs bilaterally and pitting edema of the left ankle. There are erythematous scaling patches on the medial side of the left ankle. Duplex ultrasonography is performed. Which of the following directions of blood flow would most likely confirm the diagnosis?", "answer": "Popliteal vein to small saphenous vein", "options": {"A": "Anterior tibial vein to popliteal vein", "B": "Popliteal vein to small saphenous vein", "C": "Femoral vein to external iliac vein", "D": "Great saphenous vein to femoral vein", "E": "Dorsal venous arch to great saphenous vein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old woman is brought to the physician by her daughter because of progressive memory loss and weakness over the past 6 months. She is now unable to perform activities of daily living and has had several falls in her apartment. She has diarrhea but has not had nausea or vomiting. She was treated for tuberculosis 10 years ago. She smoked half a pack of cigarettes daily for 25 years but stopped 8 years ago. She drinks a pint of vodka daily. Vital signs are within normal limits. Examination shows glossitis and a hyperpigmented rash on her face and arms. There are multiple bruises over both arms. On mental status examination, she is oriented to place and person only. Short-term memory is impaired; she can recall 0 out of 5 objects after 10 minutes. Which of the following deficiencies is most likely present in this patient?", "answer": "Vitamin B3 (niacin)", "options": {"A": "Vitamin B5 (panthothenic acid)", "B": "Vitamin B7 (biotin)", "C": "Vitamin B2 (riboflavin)", "D": "Vitamin B6 (pyridoxine)", "E": "Vitamin B3 (niacin)"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-month old child is brought to the ER by parents for one day of fever, decreased feeding, and lethargy. They report that neither she nor her siblings are immunized due to their concerns about vaccinations. On exam, the infant is toxic-appearing. Antibiotics are started and lumbar puncture reveals bacterial meningitis caused by a gram-negative, encapsulated organism that requires chocolate agar and the two factors shown in Image A for growth. Which organism does this best describe?", "answer": "Haemophilus influenza", "options": {"A": "Group B Streptococcus", "B": "Moraxella catarrhalis", "C": "Streptococcus pneumoniae", "D": "Haemophilus influenza", "E": "Listeria monocytogenes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Two days after hospital admission, a 32-year-old woman with breast cancer is visited by the attending physician in the presence of medical students. She has limited English proficiency. The attending physician describes the situation to the patient in English, and the patient nods understandably. Subsequently, the attending physician pulls down the patient’s hospital gown and exposes her breasts. The patient is clearly shocked and upset. Her unease grows as the attending physician starts to palpate her breasts and she pulls up her gown in disbelief. Which of the following actions is most likely to improve similar miscommunications in the future?", "answer": "Hiring a qualified medical interpreter in patients’ native languages", "options": {"A": "Asking a family member who knows English to interpret physician requests", "B": "Employing medical staff with above-average familiarity with a language other than English", "C": "Hiring a qualified medical interpreter in patients’ native languages", "D": "Limiting encounters with such patients to noneducational visits", "E": "Providing written forms in different languages to bridge communication gaps"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old G3P2 woman currently 39 weeks pregnant presents to the emergency department with painful vaginal bleeding shortly after a motor vehicle accident in which she was a passenger. She had her seat belt on and reports that the airbag deployed immediately upon her car's impact against a tree. She admits that she actively smokes cigarettes. Her prenatal workup is unremarkable. Her previous pregnancies were remarkable for one episode of chorioamnionitis that resolved with antibiotics. Her temperature is 98.6°F (37°C), blood pressure is 90/60 mmHg, pulse is 130/min, and respirations are 20/min. The fetal pulse is 110/min. Her uterus is tender and firm. The remainder of her physical exam is unremarkable. What is the most likely diagnosis?", "answer": "Placental abruption", "options": {"A": "Preeclampsia", "B": "Preterm labor", "C": "Vasa previa", "D": "Placental abruption", "E": "Eclampsia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A potassium hydroxide preparation is conducted on a skin scraping of the hypopigmented area. Microscopy of the preparation shows long hyphae among clusters of yeast cells. Based on these findings, which of the following is the most appropriate pharmacotherapy?", "answer": "Topical selenium sulfide", "options": {"A": "Oral fluconazole", "B": "Topical corticosteroid", "C": "Oral ketoconazole", "D": "Topical selenium sulfide", "E": "Topical nystatin\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 26-year-old woman presents to her physician at the 3rd week postpartum with a fever and a swollen breast with redness and tenderness. She has been breastfeeding her infant since birth. The symptoms of the patient started 4 days ago. She has not taken any antibiotics for the past 12 months. She does not have any concurrent diseases. The vital signs include: blood pressure 110/80 mm Hg, heart rate 91/min, respiratory rate 15/min, and temperature 38.8℃ (101.8℉). Physical examination reveals redness and enlargement of the right breast. The breast is warm and is painful at palpation. There is purulent discharge from the nipple. No fluctuation is noted. Which of the following is a correct management strategy for this patient?", "answer": "Prescribe dicloxacillin and encourage continuing breastfeeding", "options": {"A": "Prescribe dicloxacillin and encourage continuing breastfeeding", "B": "Prescribe dicloxacillin and bromocriptine for halting lactation", "C": "Manage with trimethoprim-sulfamethoxazole and encourage continuing breastfeeding", "D": "Prescribe trimethoprim-sulfamethoxazole and recommend emptying affected breast without feeding", "E": "Manage with clindamycin and recommend to interrupt breastfeeding until the resolution"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 6-month-old boy is brought to the emergency department by his mother, who informs the doctor that her alcoholic husband hit the boy hard on his back. The blow was followed by excessive crying for several minutes and the development of redness in the area. On physical examination, the boy is dehydrated, dirty, and irritable and when the vital signs are checked, they reveal tachycardia. He cries immediately upon the physician touching the area around his left scapula. The doctor strongly suspects a fracture of the 6th, 7th, or 8th retroscapular posterior ribs. Evaluation of his skeletal survey is normal. The clinician is concerned about child abuse in this case. Which of the following is the most preferred imaging technique as the next step in the diagnostic evaluation of the infant?", "answer": "Skeletal survey in 2 weeks", "options": {"A": "Babygram", "B": "Bedside ultrasonography", "C": "Chest computed tomography scan", "D": "Magnetic resonance imaging", "E": "Skeletal survey in 2 weeks"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 21-year-old man presents to the emergency department with a 1-week history of increasing knee pain. Specifically, he says that the pain is severe enough that he is no longer able to bend his knee. His past medical history is not significant, but he says that he is sexually active with multiple partners. On physical exam, his right knee is found to be swollen, erythematous, and tender to palpation. Laboratory testing demonstrates an elevated erythrocyte sedimentation rate and C-reactive protein. Which of the following properties describes the organism that is most likely responsible for this patient's symptoms?", "answer": "Gram-negative diplococci", "options": {"A": "Gram-negative diplococci", "B": "Gram-negative rod", "C": "Gram-positive cocci in chains", "D": "Gram-positive cocci in clusters", "E": "Tick born gram-variable"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 30-year-old man presents with fever, malaise, and severe pain in his right wrist and left knee for the last 2 days. He describes the pain as 8/10 in intensity, sharp in character, and extending from his right wrist to his fingers. He denies any recent inciting trauma or similar symptoms in the past. His past medical history is unremarkable. He is sexually active with multiple partners and uses condoms inconsistently. The vital signs include blood pressure 120/70 mm Hg, pulse 100/min, and temperature 38.3°C (101.0°F). On physical examination, the right wrist and left knee joints are erythematous, warm, and extremely tender to palpation. Both joints have a significantly restricted range of motion. A petechial rash is noted on the right forearm. An arthrocentesis is performed on the left knee joint. Which of the following would be the most likely finding in this patient?", "answer": "Arthrocentesis aspirate showing minimal, purulent joint effusion with negative culture", "options": {"A": "Arthrocentesis aspirate showing gram-positive cocci in clusters", "B": "Arthrocentesis aspirate showing minimal, purulent joint effusion with negative culture", "C": "Positive serum ASO titer", "D": "Radiographs of right wrist and left knee showing osteopenia and joint space narrowing", "E": "Arthrocentesis aspirate showing negatively birefringent crystals under polarised light"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man presents with 2 months of diarrhea, abdominal pain, and fatigue. He reports a weight loss of 4 kg (8 lb). He also says his joints have been hurting recently, as well. Past medical history is unremarkable. Review of systems is significant for problems with concentration and memory. Physical examination is unremarkable. A GI endoscopy is performed with a biopsy of the small bowel. Which of the following histologic finding would most likely be seen in this patient?", "answer": "PAS positive macrophages", "options": {"A": "PAS positive macrophages", "B": "Blunting of the villi", "C": "Non-caseating granulomas in the small intestine", "D": "Absence of nerves in the myenteric plexus", "E": "Presence of C. trachomatis in urine specimen"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old man who recently immigrated to the United States with his family is diagnosed with an autosomal dominant disorder that causes anemia by extravascular hemolysis. The doctor explains that his red blood cells (RBCs) are spherical, which decreases their lifespan and explains that a splenectomy may be required in the future. Which of the following is most likely to be defective in this patient?", "answer": "Spectrin", "options": {"A": "Iron absorption", "B": "Glucose-6-phosphatase dehydrogenase", "C": "Decay accelerating factor", "D": "Spectrin", "E": "Glycosylphosphatidylinositol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old African-American woman presents to her primary care physician for a general checkup appointment. She works as a middle school teacher and has a 25 pack-year smoking history. She has a body mass index (BMI) of 22 kg/m^2 and is a vegetarian. Her last menstrual period was 1 week ago. Her current medications include oral contraceptive pills. Which of the following is a risk factor for osteoporosis in this patient?", "answer": "Smoking history", "options": {"A": "Age", "B": "Body mass index", "C": "Estrogen therapy", "D": "Race", "E": "Smoking history"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old man comes to the physician for the evaluation of painful swallowing and retrosternal pain over the past 2 days. He was recently diagnosed with HIV infection, for which he now takes tenofovir, emtricitabine, and raltegravir. There is no family history of serious illness. He has smoked one pack of cigarettes daily for the past 20 years. He drinks 2–3 beers per day. He does not use illicit drugs. Vital signs are within normal limits. Physical examination of the oral cavity shows no abnormalities. The patient's CD4+ T-lymphocyte count is 80/mm3 (normal ≥ 500). Empiric treatment is started. Two weeks later, he reports no improvement in his symptoms. Esophagogastroduodenoscopy is performed and shows multiple well-circumscribed, round, superficial ulcers in the upper esophagus. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Infection with herpes simplex virus", "options": {"A": "Infection with herpes simplex virus", "B": "Transient lower esophageal sphincter relaxation", "C": "Allergic inflammation of the esophagus", "D": "Degeneration of inhibitory neurons within the myenteric plexuses", "E": "Infection with cytomegalovirus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 16-year-old male presents to the cardiologist after passing out during a basketball practice. An echocardiogram confirmed the diagnosis of hypertrophic cardiomyopathy. The cardiologist advises that a pacemaker must be implanted to prevent any further complications and states the player cannot play basketball anymore. Unfortunately, the coach objects to sidelining the player since a big game against their rivals is next week. The coach asks if the pacemaker can be implanted after the game, which of the following steps should the physician take?", "answer": "Recommend to the legal guardian that the player stop playing and have the procedure performed", "options": {"A": "Allow the patient to play and schedule a follow up after the game", "B": "Postpone the procedure so the patient can play", "C": "Perform the procedure immediately so that both the physician and coach's wishes may be fulfilled", "D": "Recommend to the legal guardian that the player stop playing and have the procedure performed", "E": "Allow the patient to make the decision regarding his health"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old girl comes to the physician because of a sore throat, fevers, and fatigue for the past 3 weeks. Her temperature is 37.8°C (100°F), pulse is 97/min, and blood pressure is 90/60 mm Hg. Examination of the head and neck shows cervical lymphadenopathy, pharyngeal erythema, enlarged tonsils with exudates, and palatal petechiae. The spleen is palpated 2 cm below the left costal margin. Her leukocyte count is 14,100/mm3 with 54% lymphocytes (12% atypical lymphocytes). Results of a heterophile agglutination test are positive. This patient is at increased risk for which of the following conditions?", "answer": "Hodgkin lymphoma", "options": {"A": "Rheumatic fever", "B": "Kaposi sarcoma", "C": "Hepatocellular carcinoma", "D": "Hodgkin lymphoma", "E": "Mycotic aneurysm"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old soldier stationed in Libya sustains a shrapnel injury during an attack, causing a traumatic above-elbow amputation. The resulting arterial bleed is managed with a tourniquet prior to transport to the military treatment facility. On arrival, he is alert and oriented to person, place, and time. His armor and clothing are removed. His pulse is 145/min, respirations are 28/min, and blood pressure is 95/52 mm Hg. Pulmonary examination shows symmetric chest rise. The lungs are clear to auscultation. Abdominal examination shows no abnormalities. There are multiple shrapnel wounds over the upper and lower extremities. A tourniquet is in place around the right upper extremity; the right proximal forearm has been amputated. One large-bore intravenous catheter is placed in the left antecubital fossa. Despite multiple attempts, medical staff is unable to establish additional intravenous access. Which of the following is the most appropriate next step in management?", "answer": "Establish intraosseous access", "options": {"A": "Irrigate the shrapnel wounds", "B": "Establish central venous access", "C": "Replace the tourniquet with a pressure dressing", "D": "Establish intraosseous access", "E": "Perform endotracheal intubation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old female presents to her physician with vesicles and tense blisters across her chest, arms, and the back of her shoulders. Physical examination reveals that blistering is not present in her oral mucosa, and the epidermis does not separate upon light stroking of the skin. The patient most likely suffers from a hypersensitivity reaction located:", "answer": "Linearly along the epidermal basement membrane", "options": {"A": "Linearly along the epidermal basement membrane", "B": "In net-like patterns around epidermal cells", "C": "In granular deposits at the tips of dermal papillae", "D": "In fat cells beneath the skin", "E": "In nuclei within epidermal cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "In 2006, three researchers from North Carolina wanted to examine the benefits of treating the risk of suicidality in children and adolescents by looking at randomized, multicenter, controlled trials of sertraline usage compared to placebo. Their analysis found clinically significant benefits of the drug and a positive benefit-to-risk ratio for sertraline in adolescents with major depressive disorder. They also found that 64 depressed children and adolescents need to receive the drug for 1 extra patient to experience suicidality as an adverse outcome. In other words, if 64 treated individuals received sertraline, some would experience suicidality due to their illness, some would not experience suicidality, and 1 individual would become suicidal due to the unique contribution of sertraline. Which of the following statements is true for this measure (defined as the inverse of the attributable risk), which aims to describe adverse outcomes this way?", "answer": "Input values must be probabilities of the events of interest.", "options": {"A": "Input values must be probabilities of the events of interest.", "B": "The final metric represents proportions in percentage terms.", "C": "The measure can include multiple events at one time.", "D": "Multiple risks can be contained and described within one result.", "E": "Higher measures indicate greater risk."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old Caucasian man presents to the clinic for evaluation of a mole on his back that he finds concerning. He states that his wife noticed the lesion and believes that it has been getting larger. On inspection, the lesion is 10 mm in diameter with irregular borders. A biopsy is performed. Pathology reveals abnormal melanocytes forming nests at the dermo-epidermal junction and discohesive cell growth into the epidermis. What is the most likely diagnosis?", "answer": "Superficial spreading melanoma", "options": {"A": "Nodular melanoma", "B": "Superficial spreading melanoma", "C": "Lentigo melanoma", "D": "Desmoplastic melanoma", "E": "Acral lentiginous melanoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old woman presents with complaints of fever, chills, and rigor. On physical exam, she also has left sided costovertebral tenderness. Vitals include a temperature of 39.4°C (103.0°F), blood pressure of 125/84 mm Hg, and pulse of 84/min. She has type 2 diabetes and is currently taking metformin daily. Urine dipstick analysis is positive for leukocytes, nitrites, and blood. The most likely cause for the present condition is?", "answer": "Acute papillary necrosis", "options": {"A": "Acute cystitis", "B": "Acute glomerulonephritis", "C": "Acute tubular necrosis", "D": "Acute interstitial nephritis", "E": "Acute papillary necrosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 70-year-old man comes to the emergency department because of severe lower back pain for 3 weeks. The pain was initially exacerbated by activity but now presents also at rest. The patient has not had a headache or a cough. He reports no changes in bowel movements or urination. He has type 2 diabetes mellitus and hypertension. He does not smoke or drink alcohol. His current medications include metformin and lisinopril. His temperature is 37.8°C (100°F), pulse is 86/min, and blood pressure is 134/92 mm Hg. Examination shows tenderness over the spinous processes of the second and third lumbar vertebrae with significant paraspinal spasm. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14 g/dL\nLeukocyte count 10,800 /mm3\nErythrocyte sedimentation rate 75 mm/h\nCRP 82 mg/L (N = 0–10 mg/L)\nSerum\nCa2+ 9.6 mg/dL\nUrea nitrogen 22 mg/dL\nGlucose 216 mg/dL\nCreatinine 1.1 mg/dL\nAlbumin 3.7 g/dL\nAlkaline phosphatase 55 U/L\nAn x-ray of the lumbar spine shows bone destruction, sequestrum formation, and periosteal reactions along the second and third lumbar vertebrae. An MRI of the lumbar spine shows increased T2 signals within the second and third lumbar vertebrae without signs of epidural abscess. A blood culture is taken and he is started on appropriate analgesia. Which of the following is the most appropriate next step in the management of this patient?\"", "answer": "CT-guided biopsy", "options": {"A": "Skeletal scintigraphy", "B": "CT-guided biopsy", "C": "Surgical debridement", "D": "Prostate-specific antigen assay", "E": "Isoniazid, rifampin, pyrazinamide, ethambutol\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman comes to the physician because of a 1-week history of left flank pain and dysuria. She has had 2 episodes of urinary tract infection over the past 2 years. Her temperature is 37°C (98.6°F) and pulse is 82/min. An ultrasound of the kidneys shows left-sided hydronephrosis and echogenic foci with acoustic shadowing. A photomicrograph of the urine is shown. The crystals observed are most likely composed of which of the following?", "answer": "Magnesium ammonium phosphate\n\"", "options": {"A": "Uric acid", "B": "Cystine", "C": "Calcium oxalate", "D": "Calcium phosphate", "E": "Magnesium ammonium phosphate\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 58-year-old woman comes to the physician because of a 2-year history of progressively worsening pain in her knees and fingers. The knee pain is worse when she walks for longer than 30 minutes. When she wakes up in the morning, her fingers and knees are stiff for about 15 minutes. She cannot recall any trauma to the joints. She was treated with amoxicillin following a tick bite 2 years ago. She is otherwise healthy and only takes a multivitamin and occasionally acetaminophen for the pain. She drinks 1–2 glasses of wine daily. She is 160 cm (5 ft 3 in) tall and weighs 79 kg (174 lb); BMI is 31 kg/m2. Her temperature is 36.9°C (98.4°F), pulse is 70/min, and blood pressure is 133/78 mm Hg. Examination of the lower extremities reveals mild genu varum. Range of motion of both knees is limited; there is palpable crepitus. Complete flexion and extension elicit pain. Tender nodules are present on the proximal and distal interphalangeal joints of the index, ring, and little fingers bilaterally. Which of the following is the most likely diagnosis?", "answer": "Osteoarthritis", "options": {"A": "Gout", "B": "Lyme arthritis", "C": "Osteoarthritis", "D": "Septic arthritis", "E": "Pseudogout"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman on prednisone for lupus presents to her primary care physician because she experiences a burning sensation with urination. She has also been urinating more frequently than normal. The patient denies fever, chills, nausea/vomiting, abdominal or back pain, or other changes with urination. Her vital signs and physical exam are unremarkable, and her urine analysis is positive for leukocyte esterase and nitrites. The patient receives a diagnosis and is then prescribed an antimicrobial that acts by inhibiting DNA gyrase. Which adverse effect should the patient be counseled about?", "answer": "Tendon rupture", "options": {"A": "Rhabdomyolysis", "B": "Leukopenia", "C": "Facial redness/flushing", "D": "Hemolytic anemia", "E": "Tendon rupture"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old boy is brought to the physician because of a cough and clear nasal secretions over the past 2 days. He is not coughing up any sputum. He says that he is the quarterback of his high school's football team and wants to get back to training as soon as possible. The patient's father had a myocardial infarction at the age of 45 years and underwent cardiac catheterization and stenting. The patient has no history of serious illness and takes no medications. His temperature is 37.8°C (100°F), pulse is 82/min, and blood pressure is 118/66 mm Hg. The lungs are clear to auscultation. Cardiac examination is shown. Which of the following is the most appropriate next step in management?", "answer": "Reassurance", "options": {"A": "Echocardiography", "B": "Cardiac stress testing", "C": "Creatine kinase and troponin T", "D": "24-hour ambulatory ECG monitoring", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "You are called to evaluate a newborn. The patient was born yesterday to a 39-year-old mother. You observe the findings illustrated in Figures A-C. What is the most likely mechanism responsible for these findings?", "answer": "Trisomy 21", "options": {"A": "Hypothyroidism", "B": "Microdeletion on chromosome 22", "C": "Maternal alcohol consumption during pregnancy", "D": "Trisomy 18", "E": "Trisomy 21"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old man presents to the emergency department with a sharp pain in the center of his chest. The pain is knife-like and constant. Sitting alleviates the pain and lying supine aggravates it. He denies the use of nicotine, alcohol or illicit drugs. Vital signs include: temperature 37.0°C (98.6°F), blood pressure 135/92 mm Hg, and pulse 97/min. On examination, a friction rub is heard at the left sternal border while the patient is leaning forward. His ECG is shown in the image. Which of the following can prevent recurrence of this patient’s condition?", "answer": "Colchicine", "options": {"A": "Ibuprofen", "B": "Colchicine", "C": "Aspirin", "D": "Glucocorticoids", "E": "Systemic antibiotics"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old man is brought in to the emergency department by his daughter. She reports that her father drank heavily for the last 16 years, but he stopped 4 days ago after he decided to quit drinking on his birthday. She also reports that he has been talking about seeing cats running in his room since this morning, although there were no cats. There is no history of any known medical problems or any other substance use. On physical examination, his temperature is 38.4ºC (101.2ºF), heart rate is 116/min, blood pressure is 160/94 mm Hg, and respiratory rate is 22/min. He is severely agitated and is not oriented to his name, time, or place. On physical examination, profuse perspiration and tremors are present. Which of the following best describes the pathophysiologic mechanism underlying his condition?", "answer": "Increased activity of NMDA receptors", "options": {"A": "Functional increase in GABA", "B": "Increased activity of NMDA receptors", "C": "Increased influx of chloride ions", "D": "Increased inhibition of norepinephrine", "E": "Increased inhibition of glutamate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 13-year-old boy is brought by his mother to the emergency department because he has had fever, chills, and severe coughing for the last two days. While they originally tried to manage his condition at home, he has become increasingly fatigued and hard to arouse. He has a history of recurrent lung infections and occasionally has multiple foul smelling stools. On presentation, his temperature is 102.2 °F (39 °C), blood pressure is 106/71 mmHg, pulse is 112/min, and respirations are 20/min. Physical exam reveals scattered rhonchi over both lung fields, rales at the base of the right lung base and corresponding dullness to percussion. The most likely organism responsible for this patient's symptoms has which of the following characteristics?", "answer": "Green gram-negative rod", "options": {"A": "Coagulase-positive, gram-positive cocci", "B": "Green gram-negative rod", "C": "Lancet-shaped diplococci", "D": "Mixed anaerobic rods", "E": "Mucoid lactose-fermenting rod"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is developing a drug that selectively inhibits the retrograde axonal transport of rabies virus towards the central nervous system. To achieve this effect, this drug must target which of the following?", "answer": "Dynein", "options": {"A": "Tubulin", "B": "Kinesin", "C": "Dynein", "D": "Nidogen", "E": "Acetylcholine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 21-year-old man comes to the physician for the evaluation of lethargy, headache, and nausea for 2 months. His headache is holocephalic and most severe upon waking up. He is concerned about losing his spot on next season's college track team, given a recent decline in his performance during winter training. He recently moved into a new house with friends, where he lives in the basement. He does not smoke or drink alcohol. His current medications include ibuprofen and a multivitamin. His mother has systemic lupus erythematosus and his father has hypertension. His temperature is 37°C (98.6°F), pulse is 80/min, respirations are 18/min, and blood pressure is 122/75 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 19.6 g/dL\nHematocrit 59.8%\nLeukocyte count 9,000/mm3\nPlatelet count 380,000/mm3\nWhich of the following is the most likely cause of this patient's symptoms?\"", "answer": "Chronic cerebral hypoxia", "options": {"A": "Chronic cerebral hypoxia", "B": "Increased intracranial pressure", "C": "Exogenous erythropoietin", "D": "Inherited JAK2 kinase mutation", "E": "Overuse of NSAIDs"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-year-old boy is brought to the physician for a well-child visit. His parents are concerned that he has not had his growth spurt yet. As a child, he was consistently in the 60th percentile for height; now he is in the 25th percentile. His classmates make fun of his height and high-pitched voice. His parents are also concerned that he does not maintain good hygiene. He frequently forgets to shower and does not seem aware of his body odor. As an infant, he had bilateral orchidopexy for cryptorchidism and a cleft palate repair. He is otherwise healthy. Vital signs are within normal limits. On physical exam, axillary and pubic hair is sparse. Genitals are Tanner stage 1 and the testicles are 2 mL bilaterally. Which of the following is the most likely diagnosis?", "answer": "Kallmann syndrome", "options": {"A": "Hyperprolactinemia", "B": "Hypothyroidism", "C": "Primary hypogonadism", "D": "Kallmann syndrome", "E": "Constitutional delay of puberty\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying the genetic profile of an isolated pathogen that proliferates within macrophages. The pathogen contains sulfatide on the surface of its cell wall to prevent fusion of the phagosome and lysosome. She finds that some of the organisms under investigation have mutations in a gene that encodes the enzyme required for synthesis of RNA from a DNA template. The mutations are most likely to reduce the therapeutic effect of which of the following drugs?", "answer": "Rifampin", "options": {"A": "Streptomycin", "B": "Rifampin", "C": "Ethambutol", "D": "Pyrazinamide", "E": "Levofloxacin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old woman comes to the physician because of a 2-week history of anal pain that occurs during defecation and lasts for several hours. She reports that she often strains during defecation and sees bright red blood on toilet paper after wiping. She typically has 3 bowel movements per week. Physical examination shows a longitudinal, perianal tear. This patient's symptoms are most likely caused by tissue injury in which of the following locations?", "answer": "Posterior midline of the anal canal, distal to the pectinate line", "options": {"A": "Posterior midline of the anal canal, distal to the pectinate line", "B": "Anterior midline of the anal canal, proximal to the pectinate line", "C": "Anterior midline of the anal canal, distal to the pectinate line", "D": "Posterior midline of the anal canal, proximal to the pectinate line", "E": "Lateral aspect of the anal canal, distal to the pectinate line"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man comes to the physician because of a 2-month history of intermittent retrosternal chest pain and tightness on exertion. He has type 2 diabetes mellitus, osteoarthritis of the right hip, and hypertension. Current medications include insulin, ibuprofen, enalapril, and hydrochlorothiazide. Vital signs are within normal limits. His troponin level is within the reference range. An ECG at rest shows a right bundle branch block and infrequent premature ventricular contractions. The patient's symptoms are reproduced during adenosine stress testing. Repeat ECG during stress testing shows new ST depression of > 1 mm in leads V2, V3, and V4. Which of the following is the most important underlying mechanism of this patient's ECG changes?", "answer": "Diversion of blood flow from stenotic coronary arteries", "options": {"A": "Ruptured cholesterol plaque within a coronary vessel", "B": "Diversion of blood flow from stenotic coronary arteries", "C": "Transient atrioventricular nodal blockade", "D": "Reduced left ventricular preload", "E": "Increased myocardial oxygen demand"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 14-year-old boy is brought to the physician by his parents for a follow-up examination. Since early childhood, he has had recurrent respiratory infections that cause him to miss several weeks of school each year. Last month, he had received treatment for his seventh episode of sinusitis this year. He has always had bulky, foul-smelling, oily stools that are now increasing in frequency. His parents are concerned that he is too thin and not gaining weight appropriately. He has a good appetite and eats a variety of foods. He is in the 10th percentile for height and the 5th percentile for weight. Examination of the nasal cavity shows multiple nasal polyps. The lung fields are clear upon auscultation. Further evaluation is most likely to show which of the following?", "answer": "Absent vas deferens", "options": {"A": "Hypersensitivity to aspirin", "B": "Absent vas deferens", "C": "Selective IgA deficiency", "D": "Positive methacholine challenge test", "E": "Anti-tissue transglutaminase antibodies\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old woman presents to her primary care provider for fatigue. She states that she has felt fatigued for the past 6 months and has tried multiple diets and sleep schedules to improve her condition, but none have succeeded. She has no significant past medical history. She is currently taking a multivitamin, folate, B12, iron, fish oil, whey protein, baby aspirin, copper, and krill oil. Her temperature is 98.8°F (37.1°C), blood pressure is 107/58 mmHg, pulse is 90/min, respirations are 13/min, and oxygen saturation is 98% on room air. Laboratory values are as seen below.\n\nHemoglobin: 8 g/dL\nHematocrit: 24%\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 147,000/mm^3\n\nPhysical exam is notable for decreased proprioception in the lower extremities and 4/5 strength in the patient's upper and lower extremities. Which of the following is the best next step in management to confirm the diagnosis?", "answer": "Anti-intrinsic factor antibodies", "options": {"A": "Anti-intrinsic factor antibodies", "B": "Bone marrow biopsy", "C": "Homocysteine level", "D": "Iron level", "E": "Transferrin level"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-month-old boy is brought to the emergency department by his mother because of lethargy and vomiting since he woke up 1 hour ago. The mother says that he last breastfed the previous evening and slept through the night for the first time. His family recently immigrated from Bolivia. His temperature is 38.7°C (101.2°F). Physical examination shows dry mucous membranes and enlarged, reddened tonsils. Serum studies show:\nGlucose 42 mg/dL\nKetones 0.2 mg/dL N = < 1 mg/dL\nAST 40 U/L\nALT 60 U/L\nAmmonia 80 μ/dL (N=15–45)\nWhich of the following enzymes is most likely deficient in this patient?\"", "answer": "Medium-chain acyl-CoA dehydrogenase", "options": {"A": "Medium-chain acyl-CoA dehydrogenase", "B": "Alpha-L-iduronidase", "C": "Galactose-1-phosphate uridyltransferase", "D": "Propionyl-CoA carboxylase", "E": "Lysosomal acid α-1,4- glucosidase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 9-year-old boy is brought to a pediatric psychologist by his mother because of poor academic performance. The patient’s mother mentions that his academic performance was excellent in kindergarten and first grade, but his second and third-grade teachers complain that he is extremely talkative, does not complete schoolwork, and frequently makes careless mistakes. They also complain that he frequently looks at other students or outside the window during the class and is often lost during the lessons. At home, he is very talkative and disorganized. When the pediatrician asks the boy his name, he replies promptly. He was born at full term by spontaneous vaginal delivery. He is up-to-date on all vaccinations and has met all developmental milestones on time. A recent IQ test scored him at 95. His physical examination is completely normal. When he is asked to read from an age-appropriate children’s book, he reads it fluently and correctly. Which of the following is the most likely diagnosis in this patient?", "answer": "Attention-deficit/hyperactivity disorder", "options": {"A": "Attention-deficit/hyperactivity disorder", "B": "Dyslexia", "C": "Persistent depressive disorder", "D": "Intellectual disability", "E": "Autism spectrum disorder"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 39-year-old man presents to a primary care clinic for a routine physical exam. He denies any complaints. He has a long beard and hair, wears several copper bracelets, and a crystal amulet. When asked about his diet, he discloses eating mostly canned foods, which he has stockpiled in his cabin in case there is a natural disaster or \"apocalypse\" (though he admits that this is highly unlikely). He has a few close friends, but feels awkward when meeting new people. He seems happy overall and has many long-standing interests, including hiking and astrology. He has been steadily employed as a data scientist and a paranormal investigator. He has never been diagnosed with a mental illness, though he has a family history of schizophrenia. Review of systems is negative for depressed mood, anxiety, or hallucinations. Thought process is linear and reality testing is intact. Which of the following is the most likely diagnosis for this patient?", "answer": "Schizotypal personality disorder", "options": {"A": "Brief psychotic disorder", "B": "Schizoid personality disorder", "C": "Schizophrenia", "D": "Schizophreniform disorder", "E": "Schizotypal personality disorder"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old woman visits her physician to seek preconception advice. She is recently married and plans to have a child soon. Menses occur at regular 28-day intervals and last 5 days. She has sexual intercourse only with her husband and, at this time, they consistently use condoms for birth control. The patient consumes a well-balanced diet with moderate intake of meat and dairy products. She has no history of serious illness and takes no medications currently. She does not smoke or drink alcohol. The patient’s history reveals no birth defects or severe genetic abnormalities in the family. Physical examination shows no abnormalities. Pelvic examination indicates a normal vagina, cervix, uterus, and adnexa. To decrease the likelihood of fetal neural-tube defects in her future pregnancy, which of the following is the most appropriate recommendation for initiation of folic acid supplementation?", "answer": "As soon as possible", "options": {"A": "As soon as her pregnancy is confirmed", "B": "As soon as possible", "C": "In the second half of pregnancy", "D": "When off contraception", "E": "No folic acid supplement is required as nutritional sources are adequate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old woman is brought to the emergency department 30 minutes after being involved in a high-speed motor vehicle collision in which she was the unrestrained driver. On arrival, she is semiconscious and incoherent. She has shortness of breath and is cyanotic. Her pulse is 112/min, respirations are 59/min, and blood pressure is 128/89 mm Hg. Examination shows a 3-cm (1.2-in) laceration on the forehead and multiple abrasions over the thorax and abdomen. There is crepitation on palpation of the thorax on the right. Auscultation of the lung shows decreased breath sounds on the right side. A crunching sound synchronous with the heartbeat is heard best over the precordium. There is dullness on percussion of the right hemithorax. The lips and tongue have a bluish discoloration. There is an open femur fracture on the left. The remainder of the examination shows no abnormalities. Arterial blood gas analysis on room air shows:\npH 7.31\nPCO2 55 mm Hg\nPO2 42 mm Hg\nHCO3- 22 mEq/L\nO2 saturation 76%\nThe patient is intubated and mechanically ventilated. Infusion of 0.9% saline is begun. Which of the following is the most likely diagnosis?\"", "answer": "Bronchial rupture", "options": {"A": "Bronchial rupture", "B": "Flail chest", "C": "Tension pneumothorax", "D": "Myocardial rupture", "E": "Pulmonary embolism"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "You are a resident on a pediatric service entering orders late at night. Upon arrival the next morning, you note that you had mistakenly ordered that low molecular weight heparin be administered to a 17-year-old patient who does not need anti-coagulation. When you talk to her, she complains about the \"shot\" she had to get this morning but is otherwise well. How should you handle the situation?", "answer": "Tell the patient and her parents about the error", "options": {"A": "You cannot disclose the error as a resident due to hospital policy", "B": "Tell the patient, but ask her not to tell her parents", "C": "Speak to risk management before deciding whether or not to disclose the error", "D": "Tell the patient and her parents about the error", "E": "Since there was no lasting harm to the patient, it is not necessary to disclose the error"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old boy presents with a history of recurrent bacterial infections, including several episodes of pneumococcal sepsis. His family history is significant for 2 maternal uncles who died from similar symptoms. Laboratory tests reveal undetectable serum levels of all isotypes of immunoglobulins and reduced levels of B cells. Which of the following is the most likely diagnosis in this patient?", "answer": "Bruton agammaglobulinemia", "options": {"A": "Bruton agammaglobulinemia", "B": "Common variable immunodeficiency", "C": "DiGeorge syndrome", "D": "Hereditary angioedema", "E": "Chediak-Higashi syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old man comes to the emergency room because of severe breathlessness for the past few hours. Over the course of a few years, he has been treated for asthma by several physicians, but his symptoms have continued to progress. He doesn’t smoke and never did. Both his father who died at the age of 40 years and his uncle (father’s brother), died with chronic obstructive pulmonary disorder. He has never smoked in his life. His respiratory rate is 19/min and temperature is 37.0°C (98.6°F). On physical examination, the patient has significantly longer exhalation than inhalation. His expiratory time is longer than 6 seconds. Clubbing is present. Chest auscultation reveals bilateral crackles. Mild hepatomegaly is present. What is the most likely diagnosis?", "answer": "α1-antitrypsin-deficiency", "options": {"A": "Pulmonary edema", "B": "Lung cancer", "C": "α1-antitrypsin-deficiency", "D": "Asthma", "E": "Pneumonia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 51-year-old woman presents to her primary care doctor with diarrhea. She has had 3-10 malodorous and loose bowel movements daily for the last 6 months, though she recalls that her bowel movements started increasing in frequency nearly 2 years ago. She was otherwise healthy until 2 years ago, when she had multiple elevated fasting blood glucose levels and was diagnosed with type 2 diabetes mellitus. She was also hospitalized once 6 months ago for epigastric pain that was determined to be due to cholelithiasis. She is an avid runner and runs 3-4 marathons per year. She is a vegetarian and takes all appropriate supplements. Her body mass index is 19 kg/m^2. She has lost 10 pounds since her last visit 18 months ago. On exam, she has dry mucous membranes and decreased skin turgor. A high-resolution spiral computerized tomography scan demonstrates a 5-cm enhancing lesion in the head of the pancreas. Additional similar lesions are found in the liver. Further laboratory workup confirms the diagnosis. The patient is offered surgery but refuses as she reportedly had a severe complication from anesthesia as a child. This patient should be treated with a combination of octreotide, 5-fluorouracil, and which other medication?", "answer": "Streptozotocin", "options": {"A": "Streptozotocin", "B": "Insulin", "C": "Paclitaxel", "D": "Glucagon", "E": "Methotrexate"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old woman presents with difficulty walking and climbing stairs for the last 3 weeks. She has no history of trauma. The physical examination reveals a waddling gait with the trunk swaying from side-to-side towards the weight-bearing limb. When she stands on her right leg, the pelvis on the left side falls, but when she stands on the left leg, the pelvis on the right side rises. Which of the following nerves is most likely injured in this patient?", "answer": "Right superior gluteal nerve", "options": {"A": "Right superior gluteal nerve", "B": "Right femoral nerve", "C": "Right inferior gluteal nerve", "D": "Right obturator nerve", "E": "Left femoral nerve"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old man presents to the emergency department with pain in his leg. He states that the pain was sudden and that his leg feels very tender. This has happened before, but symptoms resolved a few days later with acetaminophen. His temperature is 98.5°F (36.9°C), blood pressure is 129/88 mmHg, pulse is 90/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam reveals clear breath sounds bilaterally and a normal S1 and S2. The patient’s right leg is red, inflamed, and tender to palpation inferior to the popliteal fossa. Which of the following is the best treatment for this patient?", "answer": "Heparin", "options": {"A": "Aspirin", "B": "Clindamycin", "C": "Heparin", "D": "Ibuprofen and rest", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old man presents to his physician with decreased libido and inability to achieve an erection. He also reports poor sleep, loss of pleasure to do his job, and depressed mood. His symptoms started a year ago, soon after his wife got into the car accident. She survived and recovered with the minimal deficit, but the patient still feels guilty due to this case. The patient was diagnosed with diabetes 6 months ago, but he does not take any medications for it. He denies any other conditions. His weight is 105 kg (231.5 lb), his height is 172 cm (5 ft 7 in), and his waist circumference is 106 cm. The blood pressure is 150/90 mm Hg, and the heart rate is 73/min. The physical examination only shows increased adiposity. Which of the following tests is specifically intended to distinguish between the organic and psychogenic cause of the patient’s condition?", "answer": "Penile tumescence testing", "options": {"A": "Penile tumescence testing", "B": "Duplex ultrasound of the penis", "C": "Biothesiometry", "D": "Injection of prostaglandin E1", "E": "Angiography"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman, otherwise healthy, presents with a non-productive cough, sore throat, and myalgia. The patient reports that her symptoms started gradually 2 weeks ago and have not improved. She has no significant past medical history and no current medications. She is a college student and denies any recent overseas travel. The patient received the flu vaccine this year, and her 2-part PPD required for school was negative. She does not smoke, drink, or use recreational drugs. The patient denies being sexually active. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 110/75 mm Hg, pulse 98/min, respirations 20/min, and oxygen saturation 99% on room air. On physical exam, the patient is alert and cooperative. The cardiac exam is normal. There are rales present bilaterally over both lung fields. The skin and conjunctiva are pale. The laboratory tests are pending. The chest X-ray is shown in the image. Which of the following laboratory findings would also commonly be found in this patient?", "answer": "Low serum levels of complement", "options": {"A": "Low serum levels of complement", "B": "Low serum ferritin and serum iron", "C": "Bite cells on peripheral smear", "D": "Schistocytes on peripheral smear", "E": "Heinz bodies on peripheral smear"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 37-year-old woman, gravida 3, para 3, comes to the physician for very painful menses that have caused her to miss at least 3 days of work during each menstrual cycle for the past 6 months. Menses occur with heavy bleeding at regular 28-day intervals. She also has constant dull pain in the pelvic region between cycles. She is otherwise healthy. She weighs 53 kg (117 lb) and is 160 cm tall; BMI is 20.7 kg/m2. Pelvic examination shows no abnormalities. Pelvic ultrasonography shows a uniformly enlarged uterus and asymmetric thickening of the myometrial wall with a poorly defined endomyometrial border. Which of the following is the most likely cause of these findings?", "answer": "Endometrial tissue within the uterine wall", "options": {"A": "Endometrial tissue within the uterine wall", "B": "Endometrial tissue in the fallopian tubes", "C": "Cystic enlargement of the ovaries", "D": "Benign smooth muscle tumors of the uterus", "E": "Infection of ovaries, fallopian tubes, and uterus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 52-year-old man is brought to the emergency department with severe epigastric discomfort and left-sided chest pain radiating to the back that began after waking up. He has also vomited several times since the pain began. He underwent an esophagogastroduodenoscopy the previous day for evaluation of epigastric pain. He has ischemic heart disease and underwent a coronary angioplasty 3 years ago. His mother died of pancreatic cancer when she was 60 years old. His current medications include aspirin, clopidogrel, metoprolol, ramipril, and rosuvastatin. He is pale, anxious, and diaphoretic. His temperature is 37.9°C (100.2°F), pulse is 140/min, respirations are 20/min, and blood pressure is 100/60 mm Hg in his upper extremities and 108/68 mm Hg in his lower extremities. Pulse oximetry on room air shows oxygen saturation at 98%. An S4 is audible over the precordium, in addition to crepitus over the chest. Abdominal examination shows tenderness to palpation in the epigastric area. Serum studies show an initial Troponin I level of 0.031 ng/mL (N < 0.1 ng/mL) and 0.026 ng/mL 6 hours later. A 12-lead ECG shows sinus tachycardia with nonspecific ST-T changes. Which of the following is the most likely diagnosis?", "answer": "Esophageal perforation", "options": {"A": "Pneumothorax", "B": "Acute pancreatitis", "C": "Esophageal perforation", "D": "Aortic dissection", "E": "Acute myocardial infarction"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old male with a history of difficult-to-treat bipolar disorder with psychotic features is under going a medication adjustment under the guidance of his psychiatrist. The patient was previously treated with lithium and is transitioning to clozapine. Which of the following tests will the patient need routinely?", "answer": "Complete blood count, weekly", "options": {"A": "Basic metabolic panel, weekly", "B": "Complete blood count, weekly", "C": "Thyroid-stimulating hormone, prior to introducing the medication", "D": "Hemoglobin A1c, weekly", "E": "Dexamethasone suppression test, monthly"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old man comes to the emergency department because of urinary and fecal incontinence for 6 hours. Earlier in the day, he suffered a fall at a construction site and sustained injuries to his back and thighs but did not seek medical attention. He took ibuprofen for lower back pain. His temperature is 36.9°C (98.4°F), pulse is 80/min, and blood pressure is 132/84 mm Hg. Examination shows tenderness over the lumbar spine, bilateral lower extremity weakness, absent ankle jerk reflexes, and preserved patellar reflexes. There is decreased rectal tone. An ultrasound of the bladder shows a full bladder. Which of the following is the most likely diagnosis?", "answer": "Conus medullaris syndrome", "options": {"A": "Spinal epidural abscess", "B": "Cerebellar stroke", "C": "Conus medullaris syndrome", "D": "Anterior spinal cord syndrome", "E": "Brown-Sequard syndrome\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 20-year-old female presents to the college health clinic concerned about a rash that has recently developed along her back and flank. Aside from a history of chronic diarrhea and flatulence, she reports being otherwise healthy. She is concerned that this rash could be either from bed bugs or possible be sexually transmitted, as she has engaged in unprotected sex multiple times over the past two years. The physician orders several lab tests and finds that the patient does indeed have chlamydia and elevated tissue transglutaminase (tTG) levels. What is the most likely cause of her rash?", "answer": "Immunologic response to gluten", "options": {"A": "Disseminiated chlamydial infection", "B": "Streptococcal meningitis infection", "C": "Immunologic response to gluten", "D": "Immunologic response to dairy", "E": "Bed bug infestation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man presents to the physician with tiredness, lethargy, bone pain, and colicky right abdominal pain for 1 month. He has no comorbidities. He does not have any significant past medical history. His height is 176 cm (5 ft 7 in), weight is 88 kg (194 lb), and his BMI is 28.47 kg/m2. The physical examination is normal, except for mild right lumbar region tenderness. Laboratory studies show:\nHemoglobin 13.5 g/dL\nSerum TSH 2.2 mU/L\nSerum calcium 12.3 mg/dL\nSerum phosphorus 1.1 mg/dL\nSerum sodium 136 mEq/L\nSerum potassium 3.5 mEq/L\nSerum creatinine 1.1 mg/dL\nUrine calcium Elevated\nAn ultrasound of the abdomen reveals a single stone in the right ureter without hydroureteronephrosis. Clinically, no evidence of malignancy was observed. An X-ray of the long bones reveals diffuse osteopenia with subperiosteal bone resorption. The serum parathyroid hormone level is tested and it is grossly elevated. What is the most appropriate next step in his management?", "answer": "99mTc sestamibi scan with ultrasound of the neck", "options": {"A": "99mTc sestamibi scan with ultrasound of the neck", "B": "CT scan of the neck", "C": "Bone scan (DEXA)", "D": "Ultrasound of the neck only", "E": "Sestamibi scan only"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old woman with type 1 diabetes mellitus and mild asthma comes to the physician for a follow-up examination. She has had several episodes of sweating, dizziness, and nausea in the past 2 months that occur during the day and always resolve after she drinks orange juice. She is compliant with her diet and insulin regimen. The physician recommends lowering her insulin dose in certain situations. This recommendation is most important in which of the following situations?", "answer": "Before exercise", "options": {"A": "During a viral infection", "B": "After large meals", "C": "Before exercise", "D": "After a stressful exam", "E": "During pregnancy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old woman seeks evaluation at the emergency room for sudden onset of pain and swelling of her left leg since last night. Her family history is significant for maternal breast cancer (diagnosed at 52 years of age) and a grandfather with bronchioloalveolar carcinoma of the lungs at 45 years of age. When the patient was 13 years old, she was diagnosed with osteosarcoma of the right distal femur that was successfully treated with surgery. The physical examination shows unilateral left leg edema and erythema that was tender to touch and warm. Homan's sign is positive. During the abdominal examination, you also notice a large mass in the left lower quadrant that is firm and fixed with irregular borders. Proximal leg ultrasonography reveals a non-compressible femoral vein and the presence of a thrombus after color flow Doppler evaluation. Concerned about the association between the palpable mass and a thrombotic event in this patient, you order an abdominal CT scan with contrast that reports a large left abdominopelvic cystic mass with thick septae consistent with ovarian cancer, multiple lymph node involvement, and ascites. Which of the following genes is most likely mutated in this patient?", "answer": "TP53", "options": {"A": "BRCA1", "B": "TP53", "C": "BRCA2", "D": "MLH1", "E": "STK11"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old man presents with fever and cough productive of rust-colored sputum and is diagnosed with community acquired pneumonia. The causative organism is isolated, and a Gram stain is shown in Figure 1. Which of the following most correctly describes additional features of the most likely causative organism?", "answer": "Catalase negative, alpha hemolytic, optochin sensitive", "options": {"A": "Catalase positive, alpha hemolytic, optochin sensitive", "B": "Catalase positive, beta hemolytic, optochin sensitive", "C": "Catalase negative, alpha hemolytic, optochin sensitive", "D": "Catalase negative, beta hemolytic, optochin sensitive", "E": "Catalase negative, alpha hemolytic, optochin resistant"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old man is brought to the emergency room by ambulance after being found unconscious in his car parked in his garage with the engine running. His wife arrives and reveals that his past medical history is significant for severe depression treated with fluoxetine. He is now disoriented to person, place, and time. His temperature is 37.8 deg C (100.0 deg F), blood pressure is 100/50 mmHg, heart rate is 100/min, respiratory rate is 10/min, and SaO2 is 100%. On physical exam, there is no evidence of burn wounds. He has moist mucous membranes and no abnormalities on cardiac and pulmonary auscultation. His respirations are slow but spontaneous. His capillary refill time is 4 seconds. He is started on 100% supplemental oxygen by non-rebreather mask. His preliminary laboratory results are as follows:\nArterial blood pH 7.20, PaO2 102 mm Hg, PaCO2 23 mm Hg, HCO3 10 mm Hg, WBC count 9.2/µL, Hb 14 mg/dL, platelets 200,000/µL, sodium 137 mEq/L, potassium 5.0 mEq/L, chloride 96 mEq/L, BUN 28 mg/dL, creatinine 1.0 mg/dL, and glucose 120 mg/dL. Which of the following is the cause of this patient's acid-base abnormality?", "answer": "Decreased oxygen delivery to tissues", "options": {"A": "Increased anions from toxic ingestion", "B": "Decreased minute ventilation", "C": "Decreased oxygen delivery to tissues", "D": "Increased metabolic rate", "E": "Decreased ability for the tissues to use oxygen"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-day-old boy is brought to the physician by his mother because of vomiting, irritability, and poor feeding. Pregnancy and delivery were uncomplicated. Physical examination shows increased muscle tone in all extremities. He appears lethargic. His diapers emit a caramel-like odor. Urine studies are positive for ketone bodies. Supplementation of which of the following is most likely to improve this patient's condition?", "answer": "Thiamine", "options": {"A": "Thiamine", "B": "Cysteine", "C": "Leucine", "D": "Tyrosine", "E": "Tetrahydrobiopterin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman presents to her primary care physician for foot pain. The patient states that she has pain in her foot and toes whenever she exerts herself or is at work. The patient is an executive at a medical device company and works 60 hours/week. She is currently training for a marathon. She has a past medical history of anxiety, constipation, and irritable bowel syndrome. Her current medications include clonazepam, sodium docusate, and hyoscyamine. Her temperature is 99.5°F (37.5°C), blood pressure is 100/60 mmHg, pulse is 50/min, respirations are 10/min, and oxygen saturation is 99% on room air. Cardiac and pulmonary exams are within normal limits. Examination of the lower extremity reveals 5/5 strength with 2+ reflexes. Palpation of the interdigital space between the third and fourth toes elicits pain and a clicking sound. Which of the following is the most likely diagnosis?", "answer": "Intermetatarsal plantar nerve neuroma", "options": {"A": "Inflammation and damage to the plantar fascia", "B": "Compression of the tibial nerve", "C": "Intermetatarsal plantar nerve neuroma", "D": "Damage to the trabeculae of the calcaneus", "E": "Anterior talofibular ligament strain"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought to the physician by his parents several weeks after the family immigrated from Russia. The parents are worried because the child appears to have trouble seeing and has not started walking. The child was born at home and has never been evaluated by a physician. During the pregnancy, the mother had a week of fever, myalgia, diffuse rash, and bilateral nontender cervical adenopathy after the family adopted a new cat. An MRI of the head is shown. Which of the following additional findings is most likely in this patient?", "answer": "Spasticity of bilateral lower extremities", "options": {"A": "Continuous machinery murmur", "B": "Pupils do not react to light but constrict with accommodation", "C": "Spasticity of bilateral lower extremities", "D": "Tuft of hair over the lumbosacral area", "E": "Loss of pain sensation in shawl distribution"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-year-old boy who recently immigrated to the United States from Africa with his family is brought to the emergency department by his mother for a progressively worsening ulcerative lesion on his jaw. His mother reports that her son’s right jaw has rapidly enlarged over the past few months. He says that it is very tender though he doesn’t recall any trauma to the site. In addition, the mother says her son hasn’t been himself the past few months with intermittent fever, weakness, and fatigue. Physical exam reveals a large, ulcerating right jaw mass that is draining serous fluid and painless cervical and axillary lymphadenopathy. Laboratory results are notable for an elevated serum lactate dehydrogenase. A biopsy of the right jaw mass is shown in the photograph. Which of the following chromosomal translocations is most likely to be found in this patient’s lesion?", "answer": "t(8;14)", "options": {"A": "t(8;14)", "B": "t(9;22)", "C": "t(11;14)", "D": "t(14;18)", "E": "t(15;17)"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An investigator is studying the teratogenicity of cigarette smoking during pregnancy. He reviews several databases containing data about birth defects and prenatal drug exposures and finds that infants exposed to cigarette smoke in utero are approximately 2 times as likely to have a particular birth defect than unexposed infants. This defect results from abnormal development during the 6th week of gestation, when the maxillary prominences grow medially and fuse first with the lateral and then the medial nasal prominence. The defect is most likely which of the following?", "answer": "Cleft lip", "options": {"A": "Cleft palate", "B": "Cleft lip", "C": "Choanal atresia", "D": "Macrognathia", "E": "Torus palatinus\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 79-year-old woman who lives alone is brought to the emergency department by her neighbor because of worsening confusion over the last 2 days. Due to her level of confusion, she is unable to answer questions appropriately. She has had type 2 diabetes mellitus for 29 years for which she takes metformin. Vital signs include: blood pressure 111/72 mm Hg, temperature 38.5°C (101.3°F), and pulse 100/min. Her fingerstick blood glucose is 210 mg/dL. On physical examination, she is not oriented to time or place and mistakes the nursing assistant for her cousin. Laboratory results are shown:\nHemoglobin 13 g/dL\nLeukocyte count 16,000/mm3\nSegmented neutrophils 70%\nEosinophils 1%\nBasophils 0.3%\nLymphocytes 25%\nMonocytes 4%\nWhich of the following is the most likely diagnosis?", "answer": "Delirium", "options": {"A": "Alzheimer's dementia", "B": "Depression", "C": "Brief psychotic disorder", "D": "Delirium", "E": "Delusional disorder"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old woman presents to the clinic with a 2-week history of headaches. She was in her usual state of health until 2 weeks ago, when she started having headaches. The headaches are throughout her whole head and rated as a 7/10. They are worse in the mornings and when she bends over. She has some mild nausea, but no vomiting. The headaches are not throbbing and are not associated with photophobia or phonophobia. On further questioning, she has noticed that she has noticed more hair than usual on her pillow in the morning and coming out in her hands when she washes her hair. The past medical history is unremarkable; she takes no prescription medications, but for the past year she has been taking an oral ‘health supplement’ recommended by her sister, which she orders over the internet. She cannot recall the supplement's name and does not know its contents. The physical exam is notable for some mild hepatomegaly but is otherwise unremarkable. This patient's presentation is most likely related to which of the following micronutrients?", "answer": "Vitamin A", "options": {"A": "Vitamin A", "B": "Vitamin B12", "C": "Vitamin C", "D": "Vitamin D", "E": "Vitamin K"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 68-year-old man presents for a screening ultrasound scan. He has been feeling well and is in his usual state of good health. His medical history is notable for mild hypertension and a 100-pack-year tobacco history. He has a blood pressure of 128/86 and heart rate of 62/min. Physical examination is clear lung sounds and regular heart sounds. On ultrasound, an infrarenal aortic aneurysm of 4 cm in diameter is identified. Which of the following is the best initial step for this patient?", "answer": "Surveillance", "options": {"A": "Beta-blockers", "B": "Surveillance", "C": "Urgent repair", "D": "Elective repair", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old woman is brought to the emergency department because of two episodes of hemoptysis over the past 24 hours. The patient has a 6-month history of severe sinusitis and bloody nasal discharge. Her vital parameters are as follows: blood pressure, 155/75 mm Hg; pulse, 75/min; respiratory rate, 14/min; and temperature, 37.9°C (100.2°F). Examination reveals red conjunctiva, and an ulcer on the nasal septum. Pulmonary auscultation indicates diffuse rhonchi. Cardiac and abdominal examinations reveal no abnormalities. Laboratory studies show:\nUrine\nBlood 3+\nProtein 2+\nRBC 10-15/hpf with dysmorphic features\nRBC cast numerous\nBased on these findings, this patient is most likely to carry which of the following antibodies?", "answer": "Antiproteinase 3 antineutrophil cytoplasmic antibody", "options": {"A": "Anticyclic citrullinated peptide antibody", "B": "Antideoxyribonuclease antibody", "C": "Antiglomerular basement membrane antibody", "D": "Antimyeloperoxidase antibody", "E": "Antiproteinase 3 antineutrophil cytoplasmic antibody"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old man is brought to the emergency department 1 hour after the abrupt onset of painless loss of vision in his left eye. Over the last several years, he has noticed increased blurring of vision; he says the blurring has made it difficult to read, but he can read better if he holds the book below or above eye level. He has smoked 1 pack of cigarettes daily for 40 years. Fundoscopic examination shows subretinal fluid and small hemorrhage with grayish-green discoloration in the macular area in the left eye, and multiple drusen in the right eye with retinal pigment epithelial changes. Which of the following is the most appropriate pharmacotherapy for this patient's eye condition?", "answer": "Ranibizumab\n\"", "options": {"A": "Ustekinumab", "B": "Ruxolitinib", "C": "Cetuximab", "D": "Etanercept", "E": "Ranibizumab\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old woman comes to the emergency department due to severe right flank pain, fever, chills, and decreased urine output. The vital signs include a temperature of 39.0°C (102.2°F), heart rate of 120/min, a regular breathing pattern, and blood pressure of 128/70 mm Hg. Cardiopulmonary auscultation is normal. In addition, tenderness is elicited by right lumbar percussion. After initiating intravenous antibiotics empirically, the condition of the patient improves significantly. However, a low urine output persists. The results of the ordered laboratory tests are as follows:\nUrine culture Proteus mirabilis, > 150,000 CFU/mL (normal range: < 100,000 CFU/mL to no bacterial growth in asymptomatic patients)\nDensity 1.030; Leukocyte esterase (+); Nitrites (+)\npH 7.8 (normal range: 4.5–8.0)\nC-reactive protein 60 mg/dL (normal range: 0–10 mg/dL)\nSerum creatinine 1.8 mg/dL (normal range: 0.6–1.2 mg/dL)\nBUN 40 mg/dL (normal range: 7–20 mg/dL)\nPlain abdominal film Complex renal calculus in the right kidney\nWhich of the following is the most likely type of stone the patient has?", "answer": "Struvite", "options": {"A": "Xanthine", "B": "Uric acid", "C": "Cystine", "D": "Struvite", "E": "Calcium oxalate"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to the pediatrician by his parents for a routine checkup. The parents note that the patient recently joined a baseball team and has had trouble keeping up with his teammates and gets short of breath with exertion. The patient has otherwise been healthy and has no known history of asthma or allergic reaction. Today, the patient’s temperature is 98.2°F (36.8°C), blood pressure is 112/72 mmHg, pulse is 70/min, and respirations are 12/min. The physical exam is notable for a heart murmur that decreases when the patient bears down. Additionally, the hand grip and rapid squatting maneuvers increase the severity of the murmur. Which of the following is likely heard on auscultation?", "answer": "Holosystolic murmur at the lower left sternal border", "options": {"A": "Continuous murmur inferior to the left clavicle", "B": "Crescendo-decrescendo systolic murmur radiating to carotids", "C": "Holosystolic murmur at the apex radiating to the axilla", "D": "Holosystolic murmur at the lower left sternal border", "E": "Late systolic murmur with a midsystolic click"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 21-year-old woman comes to the physician because she had a positive pregnancy test at home. For the past 3 weeks, she has had nausea and increased urinary frequency. She also had three episodes of non-bloody vomiting. She attends college and is on the varsity soccer team. She runs 45 minutes daily and lifts weights for strength training for 1 hour three times per week. She also reports that she wants to renew her ski pass for the upcoming winter season. Her vital signs are within normal limits. Physical examination shows no abnormalities. Which of the following is the most appropriate recommendation?", "answer": "Stop playing soccer, continue strength training, and do not buy a ski pass", "options": {"A": "Continue playing soccer, continue strength training, and do not buy a ski pass", "B": "Stop playing soccer, stop strength training, and do not buy a ski pass", "C": "Continue playing soccer, stop strength training, and do not buy a ski pass", "D": "Stop playing soccer, continue strength training, and buy a ski pass", "E": "Stop playing soccer, continue strength training, and do not buy a ski pass"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old man is brought to the emergency department because of a 2-day history of confusion and rapidly progressive dyspnea. He has had a fever and chills for the past five days. Five years ago, he was diagnosed with hepatitis C. He has smoked two packs of cigarettes daily for 15 years and drinks one to two beers daily. He has a history of past intravenous heroin use. He appears pale, anxious, and in severe distress. His temperature is 39.3°C (102.7°F), respirations are 30/min, pulse is 59/min, and blood pressure is 80/50 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 75%. Examination shows multiple linear hemorrhages underneath the nails. There are nontender maculae on both palms and soles. Fine rales are heard bilaterally on auscultation of the chest. Cardiac examination shows an S3; a grade 3/6 high-pitched decrescendo early diastolic murmur is heard along the left sternal border and right second intercostal space. An x-ray of the chest shows a normal sized heart and pulmonary edema. An ECG shows P waves and QRS complexes that occur at regular intervals, but independently of each other. A transesophageal echocardiography (TEE) is most likely to show which of the following?", "answer": "Perivalvular thickening with an echolucent cavity", "options": {"A": "A highly echogenic, thin, linear structure in the right atrium", "B": "Anechoic space between pericardium and epicardium", "C": "Perivalvular thickening with an echolucent cavity", "D": "Oscillating mobile mass on the tricuspid valve", "E": "Eccentric hypertrophy of the left ventricle"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 10-year-old girl is admitted to the medical floor for a respiratory infection. The patient lives in a foster home and has been admitted many times. Since birth, the patient has had repeated episodes of pain/pressure over her frontal sinuses and a chronic cough that produces mucus. She was recently treated with amoxicillin for an infection. The patient is in the 25th percentile for height and weight which has been constant since birth. Her guardians state that the patient has normal bowel movements and has been gaining weight appropriately. The patient has a history of tricuspid stenosis. She also recently had magnetic resonance imaging (MRI) of her chest which demonstrated dilation of her airways. Her temperature is 99.5°F (37.5°C), blood pressure is 90/58 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 94% on room air. Physical exam is notable for bruises along the patient's shins which the guardians state are from playing soccer. The rest of the exam is deferred because the patient starts crying. Which of the following findings is associated with this patient's most likely underlying diagnosis?", "answer": "Diastolic murmur best heard along the right lower sternal border", "options": {"A": "Diastolic murmur best heard along the right lower sternal border", "B": "Hypocalcemia", "C": "Increased chloride in the patient's sweat", "D": "Repeat sinus infections secondary to seasonal allergies", "E": "Social withdrawal and avoidance of eye contact"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old man comes to the physician for a follow-up examination. He has a 3-month history of a nonproductive cough. He has been treated with diphenhydramine since his last visit 2 weeks ago, but his symptoms have persisted. He does not smoke. He drinks 3 beers on the weekends. He is 177 cm (5 ft 10 in) tall and weighs 100 kg (220.46 lbs); BMI is 35.1 kg/m2. His temperature is 37.1°C (98.8°F), pulse is 78/min, respirations are 14/min, and blood pressure is 130/80 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. Physical examination and an x-ray of the chest show no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Pulmonary function testing", "options": {"A": "Azithromycin therapy", "B": "Pulmonary function testing", "C": "Omeprazole therapy", "D": "Oral corticosteroid therapy", "E": "CT scan of the chest"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 70-year-old man with a recent above-the-knee amputation of the left lower extremity, due to wet gangrene secondary to refractory peripheral artery disease, presents with weakness and dizziness. He says that the symptoms began acutely 24 hours after surgery and have not improved. The amputation was complicated by substantial blood loss. He was placed on empiric antibiotic therapy with ciprofloxacin and clindamycin before the procedure, and blood and wound culture results are still pending. The medical history is significant for type 2 diabetes mellitus and hypertension. Current medications are metformin and lisinopril. The family history is significant for type 2 diabetes mellitus in both parents. Review of symptoms is significant for palpitations and a mild headache for the past 24 hours. His temperature is 38.2°C (100.8°F); blood pressure, 120/70 mm Hg (supine); pulse, 102/min; respiratory rate, 16/min; and oxygen saturation, 99% on room air. When standing, the blood pressure is 90/65 mm Hg and the pulse is 115/min. On physical examination, the patient appears pale and listless. The surgical amputation site does not show any signs of ongoing blood loss or infection. Laboratory tests and an ECG are pending. Which of the following is the next best step in management?", "answer": "Administer IV fluids and withhold lisinopril", "options": {"A": "Administer IV fluids and withhold lisinopril", "B": "Administer oral midodrine", "C": "Administer oral fludrocortisone", "D": "Administer IV norepinephrine", "E": "Administer IV fluids"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 31-year-old African American woman presents to her primary care provider complaining of stiff, painful fingers. She reports that her symptoms started 2 years ago and have gradually worsened. Her pain is not relieved by ibuprofen or acetaminophen. She is most concerned about having occasional episodes in which her fingers become extremely painful and turn white then pale blue. Her past medical history is notable for hypertension but she has previously refused to take any medication. She works as a postal worker and spends most of her time outside. Physical examination reveals induration of her digits with loss of skin fold wrinkles. She has limited finger range of motion. She would like to know if she can do anything to address her intermittent finger pain as it is affecting her ability to work outside in the cold. Which of the following medications is most appropriate to address this patient’s concerns?", "answer": "Nifedipine", "options": {"A": "Ambrisentan", "B": "Diltiazem", "C": "Enalapril", "D": "Methotrexate", "E": "Nifedipine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old woman comes to the physician because of easy bruising and fatigue. She appears pale. Her temperature is 38°C (100.4°F). Examination shows a palm-sized hematoma on her left leg. Abdominal examination shows an enlarged liver and spleen. Her hemoglobin concentration is 9.5 g/dL, leukocyte count is 12,300/mm3, platelet count is 55,000/mm3, and fibrinogen concentration is 120 mg/dL (N = 150–400). Cytogenetic analysis of leukocytes shows a reciprocal translocation of chromosomes 15 and 17. Which of the following is the most appropriate treatment for this patient at this time?", "answer": "All-trans retinoic acid", "options": {"A": "Platelet transfusion", "B": "Rituximab", "C": "All-trans retinoic acid", "D": "Imatinib", "E": "Cyclophosphamide"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old woman presents to her primary care physician for evaluation of 3 months of increasing fatigue. She states that she feels normal in the morning, but that her fatigue gets worse throughout the day. Specifically, she says that her head drops when trying to perform overhead tasks. She also says that she experiences double vision when watching television or reading a book. On physical exam, there is right-sided ptosis after sustaining upward gaze for a 2 minutes. Which of the following treatments may be effective in treating this patient's diagnosis?", "answer": "Thymectomy", "options": {"A": "Antitoxin", "B": "Chemotherapy", "C": "Riluzole", "D": "Thymectomy", "E": "Vaccination"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 20-year-old male is brought to a psychiatrist by his parents for bizarre behavior. His parents report that over the past two semesters in school, his personality and behavior have changed noticeably. He refuses to leave his room because he believes people are spying on him. He hears voices that are persecutory and is convinced that people at school have chips implanted in their brains to spy on him. Screenings for depression and mania are negative. His past medical history is unremarkable. His family history is notable for a maternal uncle with bipolar disorder. He does not drink alcohol or smoke. His temperature is 98.8°F (37.1°C), blood pressure is 115/70 mmHg, pulse is 85/min, and respirations are 18/min. On examination, he appears to be responding to internal stimuli. Which of the following pathways is primarily responsible for these symptoms?", "answer": "Mesolimbic pathway", "options": {"A": "Mesolimbic pathway", "B": "Mesocortical pathway", "C": "Nigrostriatal pathway", "D": "Tuberoinfundibular pathway", "E": "Papez circuit"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old man comes to the physician because of a 3-month history of diffuse perineal and scrotal pain. On a 10-point scale, he rates the pain as a 5 to 6. He reports that during this time he also has pain during ejaculation and dysuria. He did not have fever. The pain is persistent despite taking over-the-counter analgesics. He has smoked one pack of cigarettes daily for 20 years. He appears healthy and well nourished. Vital signs are within normal limits. Abdominal and scrotal examination shows no abnormalities. Rectal examination shows a mildly tender prostate without asymmetry or induration. Laboratory studies show:\nHemoglobin 13.2 g/dL\nLeukocyte count 5000/mm3\nPlatelet count 320,000/mm3\nUrine\nRBC none\nWBC 4-5/hpf\nA urine culture is negative. Analysis of expressed prostatic secretions shows 6 WBCs/hpf (N <10). Scrotal ultrasonography shows no abnormalities. Which of the following is the most likely diagnosis?\"", "answer": "Chronic pelvic pain syndrome", "options": {"A": "Prostatic abscess", "B": "Benign prostatic hyperplasia", "C": "Chronic pelvic pain syndrome", "D": "Chronic epididymitis", "E": "Bladder neck cancer"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 57-year-old man presents to the emergency department for evaluation of slurred speech and left arm and leg weakness over the last 3 hours. History reveals hypertension that is being treated with hydrochlorothiazide. Vital signs include: blood pressure of 110/70 mm Hg, heart rate 104/min, respiratory rate 18/min, and temperature 36.6°C (98.0°F). Physical examination reveals 2/5 strength in both left upper and lower extremities. After 2 hours, the patient’s symptoms suddenly disappear. An electrocardiogram (ECG) is obtained (see image). Which of the following medications could prevent ischemic attacks in this patient in the future?", "answer": "Warfarin", "options": {"A": "Acetylsalicylic acid", "B": "Clopidogrel", "C": "Enoxaparin", "D": "Heparin", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 36-year-old man was sent to the Emergency Department after a stray baseball hit him in the left eye during a game. Paramedics on sight could not perform the necessary testing and encouraged the patient to visit an ED for further testing and imaging. At the Emergency Department, the patient complains of slight pain in the orbital region and minimal diplopia that mildly increases with upward gaze. The patient’s blood pressure is 110/60 mm Hg, heart rate is 53/min, respiratory rate is 13/min, and temperature 36.6℃ (97.9℉). On physical examination, the patient is alert and responsive. There is an ecchymosis involving the lower lid and infraorbital area on the left side, with a slight downward deviation of the left globe, and conjunctival injection of the left eye. An upward gaze is limited on the left side. The visual acuity is 5/20 bilaterally. A head and neck CT shows a small (0.4 cm), nondisplaced, linear fracture of the left orbital floor. Which of the following statements about the condition the patient presents with is the most accurate?", "answer": "The patient can be initially managed conservatively with corticosteroids and observation.", "options": {"A": "The patient’s condition warrants emergency surgery.", "B": "MRI is the best method to evaluate the patient’s condition.", "C": "There is a low chance of spontaneous improvement of the ocular motility.", "D": "The patient can be initially managed conservatively with corticosteroids and observation.", "E": "Surgical intervention within 3 days would allow to prevent enophthalmos in this patient."}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old primigravid woman at 36 weeks' gestation is admitted to the hospital 30 minutes after the onset of labor. On arrival, contractions occur every 8–10 minutes. During the last 2 days she has noted decreased fetal movements. The pregnancy had been complicated by gestational hypertension. Current medications include labetalol and a pregnancy multivitamin. Her temperature is 36.8°C (98.2°F), pulse is 94/min, and blood pressure is 154/96 mm Hg. On pelvic examination, the cervix is 40% effaced and 2 cm dilated; the vertex is at -2 station. The uterus is consistent in size with a 30-week gestation. Ultrasonography shows the fetus in vertex position and a decreased amount of amniotic fluid. A fetal heart tracing is shown. Which of the following is the most likely diagnosis?", "answer": "Placental insufficiency", "options": {"A": "Umbilical cord prolapse", "B": "Umbilical cord compression", "C": "Physiologic fetal heart rate pattern", "D": "Placental insufficiency", "E": "Chorioamnionitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2-year-old male presents to the pediatrician for abdominal pain. The patient’s parents report that he has been experiencing intermittent abdominal pain for two days. Each episode lasts several minutes, and the patient seems to be entirely well between the episodes. The pain seems to improve when the patient squats on the ground with his knees to his chest. The patient’s parents also endorse decreased appetite for two days and report that his last bowel movement was yesterday. Three days ago, the patient had two episodes of blood-streaked stools, which then seemed to resolve. His parents were not concerned at the time because the patient did not seem to be in any pain. They deny any other recent upper respiratory or gastrointestinal symptoms. The patient’s past medical history is otherwise unremarkable. His temperature is 98.2°F (36.8°C), blood pressure is 71/53 mmHg, pulse is 129/min, and respirations are 18/min. The patient is happily playing in his mother’s lap. His abdomen is soft and non-distended, and he is diffusely tender to palpation over the entire right side. A 2x4 cm cylindrical mass can be palpated in the right upper quadrant.\n\nWhich of the following is most likely to be found in this patient?", "answer": "Positive technetium-99m scan", "options": {"A": "Henoch-Schonlein purpura", "B": "Hypertrophy of Peyer’s patches", "C": "Positive stool culture", "D": "Positive technetium-99m scan", "E": "Resolution with dietary modification"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 41-year-old female complains of frequent diarrhea and abdominal pain between meals. Endoscopy reveals a duodenal ulcer distal to the duodenal bulb. CT scan of the abdomen demonstrates a pancreatic mass, and subsequent tissue biopsy of the pancreas reveals a malignant islet cell tumor. Which of the following hormones is likely to be markedly elevated in this patient:", "answer": "Gastrin", "options": {"A": "Gastrin", "B": "Cholecystokinin", "C": "Secretin", "D": "Vasoactive intestinal peptide", "E": "Motilin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 9-year-old boy is brought to the physician by his father, who is concerned because his son has been less interested in playing soccer with him recently. The father and son used to play every weekend, but the son now tires easily and complains of pain in his lower legs while running around on the soccer field. The patient has no personal or family history of serious illness. Cardiac examination reveals a systolic ejection murmur best heard over the left sternal border that radiates to the left paravertebral region. A chest X-ray shows erosions on the posterior aspects of the 6th to 8th ribs. If left untreated, this patient is at the greatest risk for which of the following?", "answer": "Intracranial hemorrhage", "options": {"A": "Abdominal aortic aneurysm", "B": "Central cyanosis", "C": "Intracranial hemorrhage", "D": "Paradoxical embolism", "E": "Right heart failure"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old woman presents to the physician with a cough that began 6 years ago, as well as intermittent difficulty in breathing for the last year. There is no significant sputum production. There is no history of rhinorrhea, sneezing or nose congestion. She has been a chronic smoker from early adulthood. Her temperature is 36.9°C (98.4°F), the heart rate is 80/min, the blood pressure is 128/84 mm Hg, and the respiratory rate is 22/min. A physical examination reveals diffuse end-expiratory wheezing with prolonged expiration on chest auscultation; breath sounds and heart sounds are diminished. There is no cyanosis, clubbing or lymphadenopathy. Her chest radiogram shows hyperinflated lungs bilaterally and a computed tomography scan of her chest is shown in the picture. Which of the following best describes the pathogenesis of the condition of this patient?", "answer": "Structural cell death mediated by Rtp801", "options": {"A": "Infiltration of the lower airway mucosa by activated eosinophils and T lymphocytes", "B": "Increased release of matrix metalloproteinase 12 (MMP-12) by neutrophils", "C": "Structural cell death mediated by Rtp801", "D": "Depletion of the periciliary fluid layer in airway cells", "E": "Activation of histone deacetylase-2"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 82-year-old man presents to the emergency department complaining of vision loss in his left eye. He states that it suddenly appeared as if a curtain was coming down over his left eye. It resolved after five minutes, and his vision has returned to normal. He has a history of coronary artery disease and type 2 diabetes. What is the most likely cause of this patient's presentation?", "answer": "Cholesterol plaque embolization", "options": {"A": "Sclerosis and narrowing of retinal vessels", "B": "Deposition of retinal metabolism byproducts", "C": "Increased intraocular pressure due to a defect in the drainage of aqueous humor", "D": "lnflammation of the optic nerve", "E": "Cholesterol plaque embolization"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old woman presents with symptoms of rectal bleeding and pruritus in the perianal region. She works as a real estate agent and has a history of gastroesophageal reflux disease (GERD). On physical examination, her spleen and liver are enlarged. A blood smear reveals teardrop red blood cells (RBCs), and a leucoerythroblastic picture with the presence of nucleated RBC precursors and immature myeloid cells. A complete blood count shows a normocytic anemia. The physician explains that her condition is due to a JAK2 mutation in one of her chromosomes. What is a characteristic bone marrow aspirate of this condition?", "answer": "Fibrous tissue with sclerotic spicules observed in early stages", "options": {"A": "Hypercellular with numerous abnormal megakaryocytes", "B": "Hypercellular bone marrow with fibrosis in later stages", "C": "Ringed sideroblasts and < 20% of myeloblasts", "D": "Fibrous tissue with sclerotic spicules observed in early stages", "E": "Hypocellular bone marrow"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman is being evaluated due to complaint of fatigue and voiding pink urine. The laboratory results are as follows:\nHb 6.7\nRed blood cell count 3.0 x 1012/L\nLeukocyte count 5,000/mm3\nPlatelets 170 x 109/L\nReticulocyte count 6%\nHematocrit 32%\nThe physician thinks that the patient is suffering from an acquired mutation in hematopoietic stem cells, which is confirmed by flow cytometry analysis that revealed these cells are CD 55 and CD 59 negative. However, the physician is interested in knowing the corrected reticulocyte count before starting the patient on eculizumab. What value does the physician find after calculating the corrected reticulocyte count?", "answer": "4.6%", "options": {"A": "0.4%", "B": "0.6%", "C": "3.1%", "D": "4.6%", "E": "0.1%"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old woman presents to the clinic for a 3-month history of painful hair loss. She was in her usual state of health until about 3 months ago when she started to develop some painfully itchy spots across her scalp. Since that time these spots have lost hair and scarred, with new spots continuing to form. On further questioning, she shares that, for the last couple of years, she has generally felt poorly, specifically noting intermittent fevers, muscle and joint pains, and fatigue. On physical exam, she has several erythematous and scaly plaques across her scalp. These areas have no hair growth, but some do demonstrate hyperpigmentation. Which of the following is the most likely diagnosis?", "answer": "Discoid lupus erythematosus (DLE)", "options": {"A": "Alopecia areata", "B": "Discoid lupus erythematosus (DLE)", "C": "Secondary syphilis", "D": "Tinea capitis", "E": "Trichotillomania"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 60-year-old woman presents to the physician because of shortness of breath and easy fatigability over the past 3 months. Her symptoms become worse with physical activity. She notes no chest pain, cough, or wheezing. Her last menstrual period was 10 years ago. She currently takes calcium and vitamin D supplements as well as a vaginal estrogen cream. For several years, her diet has been poor, as she often does not feel like eating. The patient’s medical history is otherwise unremarkable. She works as a piano teacher at the local community center. She does not use tobacco or illicit drugs and enjoys an occasional glass of red wine with dinner. Her vital signs include: pulse 100/min, respiratory rate 16/min, and blood pressure 140/84 mm Hg. Physical examination reveals impaired vibratory sensation in the legs. Pallor is evident on her hands. Which of the following laboratory tests is expected to be abnormal in this patient?", "answer": "Serum methylmalonic acid level", "options": {"A": "Erythrocyte glutathione reductase activity", "B": "Erythrocyte pyruvate kinase activity", "C": "Serum folate level", "D": "Serum methylmalonic acid level", "E": "Serum protoporphyrin level"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Two weeks after returning from vacation in Mexico, a 21-year-old man comes to the emergency department because of malaise, nausea, vomiting, fever, and abdominal pain. He has no history of serious illness and takes no medications. Physical examination shows scleral icterus and right upper quadrant tenderness. The liver is palpated 1.5 cm below the right costal margin. A biopsy specimen of this patient's liver would most likely show which of the following findings?", "answer": "Ballooning degeneration and bridging necrosis", "options": {"A": "Ground glass hepatocytes and apoptotic bodies", "B": "Dysplastic hepatocytes with intracellular bile", "C": "Ballooning degeneration and bridging necrosis", "D": "Lymphocytic infiltration and progressive ductopenia", "E": "Piecemeal necrosis and fatty changes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-year-old woman comes to the physician because of a 2 week history of anorexia and a feeling of dryness in the mouth; she has had a 5.8-kg (12.8-lb) weight loss during this period. She also complains of fatigue and inability to carry out daily chores. One year ago, she was diagnosed with advanced cervical carcinoma, metastatic to the pancreas, and is being treated with combination chemotherapy. She is 157 cm (5 ft 2 in) tall and weighs 47 kg (103.6 lb); BMI is 19.1 kg/m2. She appears thin and pale. Her temperature is 37.7°C (99.8°F), blood pressure is 110/68 mm Hg, pulse is 105/min, and respirations are 28/min. There is generalized weakness and atrophy of the skeletal muscles. Which of the following is the most appropriate next step in management?", "answer": "Megestrol acetate", "options": {"A": "Dronabinol", "B": "Mirtazapine", "C": "Megestrol acetate", "D": "Cyproheptadine", "E": "Cognitive behavioral therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman is brought to the psychiatric emergency room after she was found naked in the street proclaiming that she was a prophet sent down from heaven to save the world. A review of the electronic medical record reveals that she has a history of an unspecified coagulation disorder. On exam, she speaks rapidly and makes inappropriate sexual comments about the physician. She is alert and oriented to person but not place, time, or situation. She is easily distracted and reports that she has not slept in 3 days. She is involuntarily admitted and is treated appropriately. Her symptoms improve and she is discharged 4 days later. She misses multiple outpatient psychiatric appointments after discharge. She is seen 5 months later and reports feeling better and that she is 3 months pregnant. Her fetus is at an increased risk for developing which of the following?", "answer": "Atrialized right ventricle", "options": {"A": "Atrialized right ventricle", "B": "Cleft palate", "C": "Failure of vertebral arch fusion", "D": "Phocomelia", "E": "Sirenomelia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 10-year-old boy is brought to the emergency department by his parents because of a dull persistent headache beginning that morning. He has nausea and has vomited twice. During the past four days, the patient has had left-sided ear pain and fever, but his parents did not seek medical attention. He is from Thailand and is visiting his relatives in the United States for the summer. There is no personal or family history of serious illness. He is at the 45th percentile for height and 40th percentile for weight. He appears irritable. His temperature is 38.5°C (101.3°F), pulse is 110/min, and blood pressure is 98/58 mm Hg. The pupils are equal and reactive to light. Lateral gaze of the left eye is limited. The left tympanic membrane is erythematous with purulent discharge. There is no nuchal rigidity. Which of the following is the most appropriate next step in management?", "answer": "MRI of the brain", "options": {"A": "Intravenous ceftriaxone and clindamycin therapy", "B": "Intravenous cefazolin and metronidazole therapy", "C": "MRI of the brain", "D": "Cranial burr hole evacuation", "E": "Lumbar puncture"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 7-year-old boy is brought to his pediatrician's office by his mother with a new onset rash. His mother says that the rash appeared suddenly yesterday. He is otherwise well. His medical history is unremarkable except for a recent upper respiratory infection that resolved without intervention two weeks ago. His temperature is 98.2°F (36.8°C), blood pressure is 110/74 mmHg, pulse is 84/min, and respirations are 18/min. Physical exam shows a well appearing child with a diffuse petechial rash. Complete blood count shows the following:\n\nHemoglobin: 12.6 g/dL\nHematocrit: 37%\nLeukocyte count: 5,100/mm^3\nPlatelet count: 65,000/mm^3\n\nWhich of the following is the best choice in management?", "answer": "Observation", "options": {"A": "Dexamethasone", "B": "Intravenous immunoglobulin (IVIg)", "C": "Observation", "D": "Rituximab", "E": "Splenectomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old man presents to his physician with recurrent episodes of facial swelling and abdominal pain. He reports that these episodes started when he was approximately 16 years of age. His mother also has similar episodes of swelling accompanied by swelling of her extremities. The vital signs include: blood pressure 140/80 mm Hg, heart rate 74/min, respiratory rate 17/min, and temperature 36.6℃ (97.8℉). His physical examination is unremarkable. The laboratory work-up shows the following findings:\nTest Result Normal range\nC1 esterase inhibitor  22% > 60%\nComplement C4 level  9 mg/dL  14–40 mg/dL\nComplement C2 level 0.8 mg/dL  1.1–3.0 mg/dL\nComplement component 1q  17 mg/dL 12–22 mg/dL\nWhich of the following anti-hypertensive medications is contraindicated in this patient?", "answer": "Fosinopril", "options": {"A": "Amlodipine", "B": "Valsartan", "C": "Fosinopril", "D": "Atenolol", "E": "Indapamide"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old boy undergoes MRI neuroimaging for the evaluation of worsening headaches and intermittent nausea upon awakening. He receives a bolus of intravenous thiopental for sedation during the procedure. Ten minutes after the MRI, the patient is awake and responsive. Which of the following pharmacological properties is most likely responsible for this patient's rapid recovery from this anesthetic agent?", "answer": "Redistribution", "options": {"A": "First-pass metabolism", "B": "Redistribution", "C": "Zero-order elimination", "D": "Ion trapping", "E": "Cytochrome P450 oxidation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old woman with osteoarthritis comes to the physician because of severe lower back and left leg pain. She has chronic lower back pain that is usually well-controlled with ibuprofen, but 3 hours ago her back pain acutely worsened after she picked up her 3-year-old granddaughter. The pain radiates from her lower back over her left outer thigh and knee towards the top of her big toe. Physical examination shows a diminished posterior tibial reflex on the left side. Muscle strength is 5/5 in all extremities and there are no sensory deficits. Steroid injection into which of the following anatomical locations is most likely to relieve her symptoms?", "answer": "Intervertebral foramen", "options": {"A": "Inferior facet joint", "B": "Intervertebral disc", "C": "Subdural space", "D": "Subarachnoid space", "E": "Intervertebral foramen"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old man presents to the emergency department complaining of difficulty in breathing for the past 2 days. He has had recurrent episodes of bacterial pneumonia in the right lower lobe during the last 6 months. His last episode of pneumonia started 7 days ago for which he is being treated with antibiotics. He has a 35-pack-year smoking history. Past medical history is significant for hypertension for which he takes lisinopril. Physical examination reveals decreased breath sounds and dullness to percussion in the right lung base. Chest X-ray reveals a large right-sided pleural effusion, and chest CT scan shows a large mass near the hilum of the right lung. Cytologic examination of pleural fluid shows evidence of malignancy. Which of the following is the most likely diagnosis of this patient?", "answer": "Small cell lung cancer", "options": {"A": "Pulmonary hamartoma", "B": "Mesothelioma", "C": "Non-small cell lung cancer", "D": "Small cell lung cancer", "E": "Metastatic lung disease"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old man comes to the physician because of a 3-day history of fatigue and yellowish discoloration of his eyes and skin. Physical examination shows mild right upper quadrant abdominal tenderness. The course of different serum parameters over the following 4 months is shown. Which of the following is the most likely explanation for the course of this patient's laboratory findings?", "answer": "Resolved acute hepatitis B infection", "options": {"A": "Chronic hepatitis B infection with low infectivity", "B": "Chronic hepatitis B infection with high infectivity", "C": "Adverse reaction to hepatitis B vaccination", "D": "Acute exacerbation of previous hepatitis B infection", "E": "Resolved acute hepatitis B infection"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old man comes to the physician because of fatigue and muscle cramps for the past 4 weeks. He has also noticed several episodes of tingling in both hands. He has not had fever or nausea. He has had a chronic cough for 10 years. He has chronic bronchitis, hypertension, and osteoarthritis of both knees. His father died from lung cancer. Current medications include salbutamol, ibuprofen, and ramipril. He has smoked 1 pack of cigarettes daily for 45 years. He is 175 cm (5 ft 9 in) tall and weighs 68 kg (163 lb); BMI is 22 kg/m2. His temperature is 36.7°C (98°F), pulse is 60/min, and blood pressure is 115/76 mm Hg. While measuring the patient's blood pressure, the physician observes carpopedal spasm. Cardiopulmonary examination shows no abnormalities. His hematocrit is 41%, leukocyte count is 5,800/mm3, and platelet count is 195,000/mm3. Serum alkaline phosphatase activity is 55 U/L. An ECG shows sinus rhythm with a prolonged QT interval. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Destruction of parathyroid glands", "options": {"A": "Multiple endocrine neoplasia", "B": "Ectopic hormone production", "C": "Medication side effect", "D": "Destruction of parathyroid glands", "E": "Vitamin D deficiency"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is studying the rate of multiplication of hepatitis C virus in hepatocytes. The viral genomic material is isolated, enzymatically cleaved into smaller fragments and then separated on a formaldehyde agarose gel membrane. Targeted probes are then applied to the gel and visualized under x-ray. Which of the following is the most likely structure being identified by this test?", "answer": "Ribonucleic acids", "options": {"A": "Ribonucleic acids", "B": "Deoxyribonucleic acids", "C": "Polypeptides", "D": "Transcription factors", "E": "Lipid-linked oligosaccharides"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old male is brought from his nursing home to the emergency department for fever, chills, dyspnea, productive cough, and oliguria over the past 72 hours. He was in his normal state of health and slowly developed breathing problems and fever. His past medical history is significant for hepatitis C, hypertension, and hypercholesterolemia. His medications include bisoprolol, hydrochlorothiazide, and atorvastatin. Upon arrival to the ED, his blood pressure is 80/48 mm Hg, pulse is 120/min, a respiratory rate of 28/min, and body temperature of 39.0°C (102.2°F). Physical examination reveals decreased breathing sounds in the base of the left lung, along with increased vocal resonance, and pan-inspiratory crackles. The abdomen is mildly distended with a positive fluid wave. The patient’s level of consciousness ranges from disoriented to drowsiness. He is transferred immediately to the ICU where vasoactive support is initiated. Laboratory tests show leukocytosis, neutrophilia with bands. Since admission 6 hours ago, the patient has remained anuric. Which of additional findings would you expect in this patient?", "answer": "Blood urea nitrogen (BUN):Serum creatinine ratio (SCr) <15:1", "options": {"A": "Urinary osmolality > 500 mOsmol/kg", "B": "Urinary osmolality < 350 mOsmol/kg", "C": "Blood urea nitrogen (BUN):Serum creatinine ratio (Cr) > 20:1", "D": "Blood urea nitrogen (BUN):Serum creatinine ratio (SCr) <15:1", "E": "Urine sodium > 40 mEq/L"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 70-year-old Caucasian male presents to the emergency room following a fall. The patient's past medical history is significant for myocardial infarction and atrial fibrillation. His home medications are unknown. The patient's head CT is shown in Image A. Laboratory results reveal an International Normalized Ratio (INR) of 6. Which of the following is the most appropriate pharmacologic therapy for this patient?", "answer": "Vitamin K", "options": {"A": "Vitamin K", "B": "Cryoprecipitate", "C": "Protamine", "D": "Platelet transfusion", "E": "Fresh frozen plasma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 26-year-old woman presents to her gynecologist with complaints of pain with her menses and during intercourse. She also complains of chest pain that occurs whenever she has her menstrual period. The patient has a past medical history of bipolar disorder and borderline personality disorder. Her current medications include lithium and haloperidol. Review of systems is notable only for pain when she has a bowel movement relieved by defecation. Her temperature is 98.2°F (36.8°C), blood pressure is 114/74 mmHg, pulse is 70/min, respirations are 14/min, and oxygen saturation is 98% on room air. Pelvic exam is notable for a tender adnexal mass. The patient's uterus is soft, boggy, and tender. Which of the following is the most appropriate method of confirming the diagnosis in this patient?", "answer": "Laparoscopy", "options": {"A": "Clinical diagnosis", "B": "Endometrial biopsy", "C": "Laparoscopy", "D": "MRI", "E": "Transvaginal ultrasound"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 47-year-old man is brought to the emergency department by police. He was forcibly removed from a bar for lewd behavior. The patient smells of alcohol, and his speech is slurred and unintelligible. The patient has a past medical history of alcohol abuse, obesity, diabetes, and Wernicke encephalopathy. The patient's currently prescribed medications include insulin, metformin, disulfiram, atorvastatin, a multi-B-vitamin, and lisinopril; however, he is non-compliant with his medications. His temperature is 98.5°F (36.7°C), blood pressure is 150/97 mmHg, pulse is 100/min, respirations are 15/min, and oxygen saturation is 96% on room air. Physical exam is notable for a palpable liver edge 2 cm inferior to the rib cage and increased abdominal girth with a positive fluid wave. Laboratory values are ordered and return as below:\n\nHemoglobin: 10 g/dL\nHematocrit: 33%\nLeukocyte count: 7,500 cells/mm^3 with normal differential\nPlatelet count: 245,000/mm^3\n\nSerum:\nNa+: 136 mEq/L\nCl-: 102 mEq/L\nK+: 4.1 mEq/L\nHCO3-: 24 mEq/L\nBUN: 24 mg/dL\nGlucose: 157 mg/dL\nCreatinine: 1.5 mg/dL\nCa2+: 9.6 mg/dL\n\nWhich of the following are the most likely laboratory values that would be seen in this patient in terms of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) (in U/L)?", "answer": "AST: 255, ALT: 130, GGT: 114", "options": {"A": "AST: 225, ALT: 245, GGT: 127", "B": "AST: 255, ALT: 130, GGT: 114", "C": "AST: 265, ALT: 205, GGT: 50", "D": "AST: 425, ALT: 475, GGT: 95", "E": "AST: 455, ALT: 410, GGT: 115"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man is seen in the hospital for a sacral rash. The patient has been hospitalized for the past 3 weeks for a heart failure exacerbation. When the nurse went to bathe him this morning, she noticed a red rash over his sacrum. The patient reports mild discomfort and denies pruritus. The patient has chronic kidney disease, urinary incontinence, ischemic cardiomyopathy, gout, and poor mobility. His current medications include aspirin, furosemide, metoprolol, lisinopril, spironolactone, and prednisone that was started for a recent gout flare. The patient’s temperature is 97°F (37.2°C), blood pressure is 110/62 mmHg, pulse is 68/min, and respirations are 13/min with an oxygen saturation of 98% on room air. On physical examination, there is a 4 cm x 6 cm patch of non-blanchable erythema over the patient’s sacrum that is mildly tender to palpation. Labs are obtained, as shown below:\n\nLeukocyte count: 10,000/mm^3 with normal differential\nHemoglobin: 15.2 g/dL\nPlatelet count: 400,000/mm^3\n\nSerum:\nNa: 138 mEq/L\nK+: 4.3 mEq/L\nCl-: 104 mEq/L\nHCO3-: 25 mEq/L\nBUN: 26 mg/dL\nCreatinine: 1.5 mg/dL\nGlucose: 185 mg/dL\n\nA hemoglobin A1c is pending. Which of the following is the best management for the patient’s most likely diagnosis?", "answer": "Repositioning", "options": {"A": "Metformin", "B": "Prophylactic oral ciprofloxacin", "C": "Repositioning", "D": "Surgical debridement", "E": "Topical silver sulfadiazine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70-year-old man with a long-standing history of diabetes mellitus type 2 and hypertension presents with complaints of constant wrist and shoulder pain. Currently, the patient undergoes hemodialysis 2 to 3 times a week and is on the transplant list for a kidney. The patient denies any recent traumas. Which of the following proteins is likely to be increased in his plasma, causing the patient’s late complaints?", "answer": "β2-microglobulin", "options": {"A": "Ig light chains", "B": "Amyloid A (AA)", "C": "Amyloid precursor protein", "D": "Urine tests will only be diagnostic of end-stage kidney disease", "E": "β2-microglobulin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 25-year-old woman presents to the clinic with complaints of dysuria and increased urinary frequency. Her urinalysis results are negative for nitrites. Urine microscopy shows the findings in figure A.\n\nWhat is the most likely cause underlying her symptoms?", "answer": "S. saprophyticus infection", "options": {"A": "E. coli infection", "B": "S. saprophyticus infection", "C": "Acute tubular necrosis", "D": "Renal calculi", "E": "Enterococci infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A newborn infant is born at 42 weeks gestation to a healthy 36-year-old G1P0. The delivery was complicated by prolonged labor and shoulder dystocia. The child is in the 87th and 91st percentiles for height and weight at birth, respectively. The mother’s past medical history is notable for diabetes mellitus and obesity. Immediately after birth, the child’s temperature is 99°F (37.2°C), blood pressure is 90/50 mmHg, pulse is 120/min, and respirations are 24/min. The child demonstrates a strong cry and pink upper and lower extremities bilaterally. The right arm is adducted and internally rotated at the shoulder and extended at the elbow. Flexion and extension of the wrist and digits appear to be intact in the right upper extremity. Which of the following muscles would most likely have normal strength in this patient?", "answer": "Triceps", "options": {"A": "Teres minor", "B": "Brachialis", "C": "Brachioradialis", "D": "Biceps", "E": "Triceps"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old woman, gravida 2, para 1, at 30 weeks' gestation comes to the physician because of headache for the past 5 days. Her pregnancy has been uncomplicated to date. Pregnancy and vaginal delivery of her first child were uncomplicated. The patient does not smoke or drink alcohol. She does not use illicit drugs. Medications include folic acid and a multivitamin. Her temperature is 37°C (98.6°F), pulse is 82/min, and blood pressure is 150/92 mm Hg. Physical examination reveals 2+ pitting edema in the lower extremities. Laboratory studies show:\nHemoglobin 11.8 g/dL\nPlatelet count 290,000/mm3\nUrine\npH 6.3\nProtein 2+\nWBC negative\nBacteria occasional\nNitrites negative\nThe patient is at increased risk of developing which of the following complications?\"", "answer": "Abruptio placentae", "options": {"A": "Placenta previa", "B": "Abruptio placentae", "C": "Spontaneous abortion", "D": "Uterine rupture", "E": "Polyhydramnios"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old boy with history of seizure disorder is rushed to the Emergency Department with multiple generalized tonic-clonic seizures that have spanned more than 30 minutes in duration. He has not regained consciousness between these episodes. In addition to taking measures to ensure that he maintains adequate respiration, which of the following is appropriate for initial pharmacological therapy?", "answer": "Lorazepam", "options": {"A": "Phenytoin", "B": "Carbamazepine", "C": "Gabapentin", "D": "Valproic acid", "E": "Lorazepam"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old woman presents to an outpatient clinic during winter for persistant rhinorrhea. She states it is persistent and seems to be worse when she goes outside. Otherwise, she states she is generally healthy and only has a history of constipation. Her temperature is 98.7°F (37.1°C), blood pressure is 144/91 mmHg, pulse is 82/min, respirations are 14/min, and oxygen saturation is 98% on room air. Nasal sputum cytology reveals eosinophilia and boggy turbinates. Which of the following is the most likely diagnosis?", "answer": "Environmental allergen", "options": {"A": "Cold weather", "B": "Coronavirus", "C": "Environmental allergen", "D": "Staphylococcus aureus", "E": "Streptococcus pneumonia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 21-year-old male presents to your office with hematuria 3 days after the onset of a productive cough and fever. Following renal biopsy, immunofluorescence shows granular IgA deposits in the glomerular mesangium. Which of the following do you suspect in this patient?", "answer": "Berger’s disease", "options": {"A": "Lipoid nephrosis", "B": "Berger’s disease", "C": "Poststreptococcal glomerulonephritis", "D": "Systemic lupus erythematosus", "E": "HIV infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 73-year-old man presents to the office, complaining of “weird blisters” on his right hand, which appeared 2 weeks ago. The patient says that he initially had a rash, which progressed to blisters. He denies any trauma or known contact with sick people. He is worried because he hasn’t been able to garden since the rash appeared, and he was planning on entering his roses into an annual competition this month. His vital signs are stable. On physical exam, the patient has multiple bullae accompanied by red, papular lesions on his right hand, which progress to his forearm. The right axillary lymph nodes are swollen and tender. What is the treatment for the most likely diagnosis of this patient?", "answer": "Itraconazole", "options": {"A": "Potassium iodide solution", "B": "Azithromycin", "C": "Doxycycline", "D": "Itraconazole", "E": "Topical corticosteroids"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old male presents to the emergency room complaining of substernal chest pain. He reports a three-hour history of dull substernal chest pain that radiates into his left arm and jaw. He had a similar incident two months ago after walking one mile, but this pain is more severe. His past medical history is notable for hypertension and hyperlipidemia. An EKG demonstrates non-specific changes. Serum troponins are normal. In addition to aspirin, oxygen, and morphine, he is started on a medication that generates endothelial nitric oxide. Which of the following is a downstream effect of this molecule?", "answer": "Guanylyl cyclase activation", "options": {"A": "Guanylyl cyclase activation", "B": "cAMP production", "C": "Prostaglandin synthesis inhibition", "D": "ß1-adrenergic antagonism", "E": "L-type calcium channel inhibition"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-year-old male is brought by his mother to the pediatrician because she is concerned about a lump in his neck. She reports that the child was recently ill with a cough, nasal congestion, and rhinorrhea. She also noticed that a small red lump developed on the patient’s neck while he was sick. Although his cough and congestion subsided after a few days, the neck lump has persisted. The child has no notable past medical history. He was born at 39 weeks gestation and is in the 55th percentiles for both height and weight. His temperature is 98.6°F (37°C), blood pressure is 105/65 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination reveals a small, soft, rounded mass at the midline of the neck inferior to the hyoid bone. The mass is warm and tender to palpation. It moves superiorly when the patient drinks water. Histologic examination of this lesion would most likely reveal which of the following?", "answer": "Follicular cells surrounding colloid and admixed with a neutrophilic infiltrate", "options": {"A": "Follicular cells surrounding colloid and admixed with a neutrophilic infiltrate", "B": "Cyst-like structure lined by stratified squamous epithelium and containing mucoid material", "C": "Randomly oriented papillae with fibrovascular cores and empty-appearing nuclei", "D": "Diffuse hyperplasia and hypertrophy of follicular cells", "E": "Stratified squamous epithelium associated with hair follicles and sebaceous glands"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 50-year-old woman presents to the outpatient clinic because of a swollen and enlarged right breast. Clinical examination shows no evidence of mass or axillary lymphadenopathy. There is no history of trauma or inflammation. Her past medical and surgical history is positive for breast augmentation with a textured implant 15 years ago. Magnetic resonance imaging (MRI) shows an accumulation of fluid around the right breast implant with intact implant integrity. Which of the following is the most appropriate next step in the management?", "answer": "Cytological analysis for CD30 and ALK", "options": {"A": "Mastectomy", "B": "Surgical replacement of textured implant with a smooth implant", "C": "Mammogram", "D": "Cytological analysis for CD30 and ALK", "E": "Chemotherapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old man presents to his primary care physician with diarrhea and weight loss. He states he has had diarrhea for the past several months that has been worsening steadily. The patient recently went on a camping trip and drank unfiltered stream water. Otherwise, the patient endorses a warm and flushed feeling in his face that occurs sporadically. His temperature is 97.2°F (36.2°C), blood pressure is 137/68 mmHg, pulse is 110/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam is notable for a murmur heard best over the left lower sternal border and bilateral wheezing on pulmonary exam. Which of the following is the best initial step in management?", "answer": "Urinary 5-hydroxyindoleacetic acid level", "options": {"A": "Echocardiography", "B": "Plasma free metanephrine levels", "C": "Pulmonary function tests", "D": "Stool culture and ova and parasite analysis", "E": "Urinary 5-hydroxyindoleacetic acid level"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old man presents to the emergency department after a motor vehicle accident. He was the unrestrained front seat driver in a head on collision. The patient is unresponsive and his medical history is unknown. His temperature is 99.5°F (37.5°C), blood pressure is 67/38 mmHg, pulse is 190/min, respirations are 33/min, and oxygen saturation is 98% on room air. The patient is started on IV fluids, blood products, and norepinephrine. A FAST exam is performed and a pelvic binder is placed. One hour later, his temperature is 98.3°F (36.8°C), blood pressure is 119/66 mmHg, pulse is 110/min, respirations are 15/min, and oxygen saturation is 97% on room air. The patient is currently responsive. Management of the patient's pelvic fracture is scheduled by the orthopedic service. While the patient is waiting in the emergency department he suddenly complains of feeling hot, aches, and a headache. The patient's temperature is currently 101°F (38.3°C). He has not been given any pain medications and his past medical history is still unknown. Which of the following is the most likely diagnosis?", "answer": "Febrile non-hemolytic transfusion reaction", "options": {"A": "Acute hemolytic transfusion reaction", "B": "Febrile non-hemolytic transfusion reaction", "C": "Leukoagglutination reaction", "D": "Minor blood group incompatibility", "E": "Sympathetic response to pain"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A newborn is rushed to the neonatal ICU after becoming cyanotic shortly after birth. An ultrasound is performed which shows the aorta coming off the right ventricle and lying anterior to the pulmonary artery. The newborn is given prostaglandin E1 and surgery is planned to correct the anatomic defect. Which of the following developmental processes failed to occur in the newborn?", "answer": "Failure of the aorticopulmonary septum to spiral", "options": {"A": "Failure of the septum primum to fuse with the septum secundum", "B": "Failure of the membranous ventricular septum to fuse with the muscular interventricular septum", "C": "Failure of the ductus arteriosus to close", "D": "Failure of the ductus venosus to close", "E": "Failure of the aorticopulmonary septum to spiral"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 48-year-old woman underwent a thyroidectomy with central neck dissection due to papillary thyroid carcinoma. On day 2 postoperatively, she developed irritability, dysphagia, difficulty breathing, and spasms in different muscle groups in her upper and lower extremities. The vital signs include blood pressure 102/65 mm Hg, heart rate 93/min, respiratory rate 17/min, and temperature 36.1℃ (97.0℉). Physical examination shows several petechiae on her forearms, muscle twitching in her upper and lower extremities, expiratory wheezes on lung auscultation, decreased S1 and S2 and the presence of an S3 on cardiac auscultation, and positive Trousseau and Chvostek signs. Laboratory studies show:\nCa2+ 4.4 mg/dL\nMg2+ 1.7 mEq/L\nNa+ 140 mEq/L\nK+ 4.3 mEq/L\nCl- 107 mEq/L\nHCO3-  25 mEq/L\nAdministration of which of the following agents could prevent the patient’s condition?", "answer": "Vitamin D and ionic calcium prior to and 2 weeks after the operation", "options": {"A": "Anticonvulsants prior to and for 1 week after the operation", "B": "Magnesium sulfate intraoperatively", "C": "Vitamin D and ionic calcium prior to and 2 weeks after the operation", "D": "Calcium gluconate intraoperatively", "E": "Potassium supplementation prior to and 2 weeks after the operation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old man presents with sudden-onset severe eye pain and blurred vision. He says the symptoms onset an hour ago and his vision has progressively worsened. Physical examination reveals a cloudy cornea and decreased visual acuity. Timolol is administered into the eyes to treat this patient’s symptoms. Which of the following best describes the mechanism of action of this drug in the treatment of this patient’s condition?", "answer": "It suppresses the ciliary epithelium from producing aqueous humor", "options": {"A": "Increased outflow via dilatation of the uveoscleral veins", "B": "It suppresses the ciliary epithelium from producing aqueous humor", "C": "It increases the transit of aqueous humor into the vitreous humor for absorption into the choroid", "D": "It leads to opening of the trabecular meshwork", "E": "It decreases the production of aqueous humor by decreasing levels of bicarbonate through a cAMP-mediated pathway"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Four days after undergoing a craniotomy and evacuation of a subdural hematoma, a 56-year-old man has severe pain and swelling of his right leg. He has chills and nausea. He has type 2 diabetes mellitus and chronic kidney disease, and was started on hemodialysis 2 years ago. Prior to admission, his medications were insulin, enalapril, atorvastatin, and sevelamer. His temperature is 38.3°C (101°F), pulse is 110/min, and blood pressure is 130/80 mm Hg. Examination shows a swollen, warm, and erythematous right calf. Dorsiflexion of the right foot causes severe pain in the right calf. The peripheral pulses are palpated bilaterally. Cardiopulmonary examination shows no abnormalities. Laboratory studies show:\nHemoglobin 10.1 g/dL\nLeukocyte count 11,800/mm3\nPlatelet count 230,000/mm3\nSerum\nGlucose 87 mg/dL\nCreatinine 1.9 mg/dL\nWhich of the following is the most appropriate next step in treatment?\"", "answer": "Inferior vena cava filter", "options": {"A": "Iliac stenting", "B": "Unfractionated heparin therapy", "C": "Inferior vena cava filter", "D": "Urokinase therapy", "E": "Warfarin therapy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 10-year-old boy is presented to the hospital for a kidney transplant. In the operating room, the surgeon connects an allograft kidney renal artery to the aorta, and after a few moments, the kidney becomes cyanotic, edematous, and dusky with mottling. Which of the following in the recipient’s serum is responsible for this rejection?", "answer": "IgG", "options": {"A": "IgA", "B": "IgG", "C": "CD8+ T cells", "D": "CD4+ T cells", "E": "Macrophages"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Background: Beta-blockers reduce mortality in patients who have chronic heart failure, systolic dysfunction, and are on background treatment with diuretics and angiotensin-converting enzyme inhibitors. We aimed to compare the effects of carvedilol and metoprolol on clinical outcome.\nMethods: In a multicenter, double-blind, and randomized parallel group trial, we assigned 1,511 patients with chronic heart failure to treatment with carvedilol (target dose 25 mg twice daily) and 1,518 to metoprolol (metoprolol tartrate, target dose 50 mg twice daily). Patients were required to have chronic heart failure (NYHA II-IV), previous admission for a cardiovascular reason, an ejection fraction of less than 0.35, and to have been treated optimally with diuretics and angiotensin-converting enzyme inhibitors unless not tolerated. The primary endpoints were all-cause mortality, the composite endpoint of all-cause mortality, or all-cause admission. Analysis was done by intention to treat\nFindings: The mean study duration was 58 months (SD 6). The mean ejection fraction was 0.26 (0.07) and the mean age was 62 years (11). The all-cause mortality was 34% (512 of 1,511) for carvedilol and 40% (600 of 1,518) for metoprolol (hazard ratio 0.83 [95% CI 0.74-0.93], p = 0.0017). The reduction of all-cause mortality was consistent across predefined subgroups. Incidence of side effects and drug withdrawals did not differ by much between the 2 study groups.\nWhich of the following represents the number of patients needed to treat to save one life?", "answer": "1/(0.40 - 0.34)", "options": {"A": "1/(0.40 - 0.34)", "B": "1/(0.34 - 0.40)", "C": "1/(40 - 34)", "D": "1/(34 - 40)", "E": "1/0.83"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 52-year-old man who was recently hospitalized with a pulmonary embolism is put on an unfractionated heparin drip as a bridge to chronic warfarin therapy. During morning rounds, he is found to have diffuse bruising despite minimal trauma, and his heparin infusion rate is found to be faster than prescribed. A coagulation panel is obtained, which shows a aPTT of 130 seconds (therapeutic 70-120 seconds), and the decision is made to reverse the effects of heparin. Which of the following would most likely be administered in order to do this?", "answer": "Protamine sulfate", "options": {"A": "Aminocaproic acid", "B": "Fresh frozen plasma", "C": "Platelets", "D": "Protamine sulfate", "E": "Vitamin K"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A new formula for an anti-wrinkle cream is being tested for efficacy in a group of 362 healthy 40- to 60-year-old female volunteers. The marketing team randomizes the volunteers. Half receive the new formula and the other half of the volunteers receive the original formula. The mean age in the test group is 48 (95% CI 42-56), and the average age of the control group is 49 (95% CI 42-55). The volunteers are unaware of which formula they receive. The research and development team then compares before and after photographs of the volunteers following 6 weeks of at home application twice daily. For simplicity, the marketing team labels the photographs with \"new formula\" or \"original formula.\" 98% of volunteers in the test group complete the study, and 97% of volunteers in the control group complete the study. The researchers conclude that there is improved wrinkle reduction with 6 weeks of use of the new formula. Which of the following potential biases most likely impacted this conclusion?", "answer": "Observer bias", "options": {"A": "Selection bias", "B": "Hawthorn effect", "C": "Observer bias", "D": "Procedure bias", "E": "Recall bias"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 49-year-old woman comes to the physician because of a 1-year history of bloating and constipation alternating with diarrhea. She eats a balanced diet, and there are no associations between her symptoms and specific foods. She had been a competitive swimmer since high school but stopped going to training 4 months ago because her fingers hurt and turned blue as soon as she got into the cold water. She drinks one to two glasses of wine daily. Physical examination shows swollen hands and fingers with wax-like thickening of the skin. There are numerous small, superficial, dilated blood vessels at the tips of the fingers. The abdomen is distended and mildly tender with no guarding or rebound. Further evaluation is most likely to show which of the following findings?", "answer": "Calcium deposits in the skin", "options": {"A": "Bilateral pupillary constriction", "B": "Outpouchings of the sigmoid colon", "C": "Villous atrophy in the duodenum", "D": "Periumbilical dilation of subcutaneous veins", "E": "Calcium deposits in the skin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 20-year-old woman is brought to the emergency department because of severe muscle soreness, nausea, and darkened urine for 2 days. The patient is on the college track team and has been training intensively for an upcoming event. One month ago, she had a urinary tract infection and was treated with nitrofurantoin. She appears healthy. Her temperature is 37°C (98.6°F), pulse is 64/min, and blood pressure is 110/70 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and non-tender. There is diffuse muscle tenderness over the arms, legs, and back. Laboratory studies show:\nHemoglobin 12.8 g/dL\nLeukocyte count 7,000/mm3\nPlatelet count 265,000/mm3\nSerum\nCreatine kinase 22,000 U/L\nLactate dehydrogenase 380 U/L\nUrine\nBlood 3+\nProtein 1+\nRBC negative\nWBC 1–2/hpf\nThis patient is at increased risk for which of the following complications?\"", "answer": "Acute kidney injury", "options": {"A": "Acute kidney injury", "B": "Compartment syndrome", "C": "Metabolic alkalosis", "D": "Myocarditis", "E": "Hemolytic anemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 56-year-old man presents for a follow-up regarding his management for type 2 diabetes mellitus (DM). He was diagnosed with type 2 DM about 7 years ago and was recently started on insulin therapy because oral agents were insufficient to control his glucose levels. He is currently following a regimen combining insulin lispro and neutral protamine Hagedorn (NPH) insulin. He is taking insulin lispro 3 times a day before meals and NPH insulin once in the morning. He has been on this regimen for about 2 months. He says that his glucose reading at night averages around 200 mg/dL and remains close to 180 mg/dL before his shot of NPH in the morning. The readings during the rest of the day range between 100–120 mg/dL. The patient denies any changes in vision or tingling or numbness in his hands or feet. His latest HbA1C level was 6.2%. Which of the following adjustments to his insulin regimen would be most effective in helping this patient achieve better glycemic control?", "answer": "Add another dose of NPH in the evening.", "options": {"A": "Add another dose of insulin lispro in the evening.", "B": "Add another dose of NPH in the evening.", "C": "Add insulin glargine to the current regime.", "D": "Replace lispro with insulin aspart.", "E": "Reduce a dose of insulin lispro."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 17-year-old high school student presents to the physician’s office for a health maintenance examination. He is a recent immigrant from Venezuela and has no complaints at this time. Past medical history is significant for appendicitis at age 10, treated with an appendectomy. He denies the use of alcohol and cigarettes. He admits to occasionally smoking marijuana with his friends. He is sexually active with 1 woman partner and uses condoms inconsistently. The vital signs are within normal limits. Physical examination is unremarkable except for a laparoscopic surgical scar on the right iliac region. Routine blood tests are pending. What is the most appropriate next step in management?", "answer": "HPV vaccine", "options": {"A": "Ceftriaxone and azithromycin as prophylaxis", "B": "Azithromycin as prophylaxis only", "C": "HPV vaccine", "D": "HPV vaccine as a legal adult at age 18", "E": "Urine toxicology"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A group of researchers aimed to study the association between phosphate levels in plasma and renal function decline in pre-dialysis patients. The study started in 2018 by including incident pre-dialysis patients (with chronic kidney disease in stage IV or V) who were already included in pre-dialysis care procedures between 2014 and 2016. These patients were subsequently found in the records of the hospitals participating in the study, and patient files were used to note the laboratory measurements at baseline. The medical courses of those patients were then followed through the medical charts (most notably their decline in renal function) until the start of dialysis, their death, or January 1, 2018. From this data, the researchers calculated that faster declines in renal function were linked to higher phosphate levels at baseline. Moreover, a relative risk for dying (1.5-fold) could be calculated for every mg/dL increase in phosphate levels. Hence, a high plasma phosphate level was shown to be an independent risk factor for not only a more rapid decline in renal function but also for higher mortality rates during the pre-dialysis phase. What is the main limitation of this type of observational study approach?", "answer": "Inability to control for specific factors", "options": {"A": "Significant time commitment", "B": "Hypotheses generation", "C": "Selection based on the exposure status", "D": "Inability to control for specific factors", "E": "Lack of inter-rater reliability"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 56-year-old man comes to the office complaining of a dry cough for 2 months. His medical history includes a recent myocardial infarction (MI), after which he was placed on several medications. He is currently on ramipril, clopidogrel, digoxin, lovastatin, and nitroglycerin. He does not smoke cigarettes and does not drink alcohol. He denies a history of bronchial asthma. Examination of the chest is within normal limits. Which of the following medications may have caused his symptom?", "answer": "Ramipril", "options": {"A": "Ramipril", "B": "Clopidogrel", "C": "Nitroglycerin", "D": "Lovastatin", "E": "Digoxin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An investigator is studying the effect of extracellular pH changes on the substrates for the citric acid cycle. Which of the following substances is required for the reaction catalyzed by the enzyme marked by the arrow in the overview of the citric acid cycle?", "answer": "Pantothenic acid", "options": {"A": "Thiamine", "B": "Pantothenic acid", "C": "Lipoic acid", "D": "Niacin", "E": "Riboflavin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old woman and her son are visited at her home by a health aid. He is her caregiver but has difficulty getting her out of the house. Her son is concerned about continuous and repetitive mouth and tongue movements that started about 2 weeks ago and have become more evident ever since. She is non-verbal at baseline and can complete most activities of daily living. She suffers from an unspecified psychiatric disorder. Her medications include fluphenazine. Today, her heart rate is 90/min, respiratory rate is 17/min, blood pressure is 125/87 mm Hg, and temperature is 37.0°C (98.6°F). On physical exam, she appears gaunt and anxious. She is drooling and her mouth is making a chewing motion that is occasionally disrupted by wagging her tongue back and forth. She seems to be performing these motions absentmindedly. Her heart has a regular rate and rhythm and her lungs are clear to auscultation bilaterally. CMP, CBC, and TSH are normal. A urine toxicology test is negative. What is the next best step in her management?", "answer": "Stop the medication", "options": {"A": "Start clozapine", "B": "Switch to chlorpromazine", "C": "Reduce the dosage", "D": "Expectant management", "E": "Stop the medication"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old woman presents to her primary care physician complaining of 3 weeks of persistent thirst despite consumption of increased quantities of water. She also admits that she has had increased frequency of urination during the same time period. A basic metabolic panel is performed which reveals mild hypernatremia and a normal glucose level. Urine electrolytes are then obtained which shows a very low urine osmolality that does not correct when a water deprivation test is performed. Blood tests reveal an undetectable level of antidiuretic hormone (ADH). Based on this information, what is the most likely cause of this patient's symptoms?", "answer": "Central diabetes insipidus", "options": {"A": "Primary polydipsia", "B": "Diabetes mellitus", "C": "Nephrogenic diabetes insipidus", "D": "Central diabetes insipidus", "E": "Surreptitious diuretic use"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old woman with no known past medical history presents to the emergency department with increasing lower pelvic pain and vaginal discharge over the last several days. She endorses some experimentation with marijuana and cocaine, drinks liquor almost daily, and smokes 2 packs of cigarettes per day. The patient's blood pressure is 84/66 mm Hg, pulse is 121/min, respiratory rate is 16/min, and temperature is 39.5°C (103.1°F). Physical examination reveals profuse yellow-green vaginal discharge and severe cervical motion tenderness. What is the most appropriate definitive treatment for this patient’s presumed diagnosis?", "answer": "Exploratory laparotomy", "options": {"A": "Levofloxacin and metronidazole × 14 days", "B": "Single-dose ceftriaxone IM", "C": "Exploratory laparotomy", "D": "Cefoxitin × 14 days", "E": "Clindamycin + gentamicin × 14 days"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 5-year-old boy presents to your office with his mother. The boy has been complaining of a sore throat and headache for the past 2 days. His mother states that he had a fever of 39.3°C (102.7°F) and had difficulty eating. On examination, the patient has cervical lymphadenopathy and erythematous tonsils with exudates. A streptococcal rapid antigen detection test is negative. Which of the following is the most likely causative agent?", "answer": "A naked, double-stranded DNA virus", "options": {"A": "A gram-negative, pleomorphic, obligate intracellular bacteria", "B": "A naked, double-stranded DNA virus", "C": "A gram-positive, beta-hemolytic cocci in chains", "D": "An enveloped, single-stranded, negative sense RNA virus", "E": "An enveloped, double-stranded DNA virus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 57-year-old man presents to his family physician for a checkup. He has had type 2 diabetes mellitus for 13 years, for which he has been taking metformin and vildagliptin. He has smoked 10–15 cigarettes daily for 29 years. Family history is irrelevant. Vital signs include: temperature 36.6°C (97.8°F), blood pressure 152/87 mm Hg and pulse 88/min. Examination reveals moderate abdominal obesity with a body mass index of 32 kg/m². The remainder of the examination is unremarkable. His fasting lipid profile is shown:\nTotal cholesterol (TC) 280 mg/dL\nLow-density lipoprotein (LDL)-cholesterol 210 mg/dL\nHigh-density lipoprotein (HDL)-cholesterol 40 mg/dL\nTriglycerides (TGs) 230 mg/dL\nWhich of the following is the mechanism of action of the best initial therapy for this patient?", "answer": "Inhibition of cholesterol synthesis", "options": {"A": "Inhibition of cholesterol absorption", "B": "Bile acid sequestration", "C": "Inhibition of adipose tissue lipolysis", "D": "Inhibition of cholesterol synthesis", "E": "Activation of PPAR-alpha"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 69-year-old man comes to the physician with a 2-year history of progressive hearing loss. His hearing is worse in crowded rooms, and he has noticed that he has more difficulty understanding women than men. He has no history of serious illness and does not take any medications. A Rinne test shows air conduction is greater than bone conduction bilaterally. This condition is most likely associated with damage closest to which of the following structures?", "answer": "Basal turn of the cochlea", "options": {"A": "External acoustic meatus", "B": "Tympanic membrane", "C": "Basal turn of the cochlea", "D": "Round window", "E": "Base of the stapes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is studying the growth of an organism in different media. The organism is inoculated on a petri dish that contains heated sheep blood, vancomycin, nystatin, trimethoprim, and colistin. The resulting growth medium is incubated at 37°C. Numerous small, white colonies are seen after incubation for 48 hours. This organism is most likely to cause which of the following conditions?", "answer": "Gonorrhea", "options": {"A": "Pseudomembranous colitis", "B": "Pontiac fever", "C": "Hemolytic uremic syndrome", "D": "Oral thrush", "E": "Gonorrhea"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "The parents of a 4-year-old present to the pediatrician because they are concerned about the poor growth and odd behavior of their son. Their son has been at the 10th percentile for growth since birth and they have noticed that his skin seems to have a bluish hue to it whenever he cries or is agitated. Recently, they have noticed that when he squats it seems to relieve these symptoms. What was the embryologic cause of this patient's current symptoms?", "answer": "Anterosuperior displacement of aorticopulmonary septum", "options": {"A": "Failure of the aorticopulmonary septum to spiral", "B": "Failure of the ductus arteriosus to obliterate", "C": "Partial aorticopulmonary septum development", "D": "Failure of septum primum and septum secundum to fuse", "E": "Anterosuperior displacement of aorticopulmonary septum"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 5-year-old boy is brought to the physician because of early morning headaches for the past 6 months. During this period, he has had severe nausea and occasional episodes of vomiting. For the past month, he has had difficulty walking and intermittent double vision. He was born at term and has been healthy apart from an episode of sinusitis 8 months ago that resolved spontaneously. He is at the 60th percentile for height and 50th percentile for weight. His temperature is 37.1°C (98.8°F), pulse is 80/min, and blood pressure is 105/64 mm Hg. Examination shows normal muscle strength and 2+ deep tendon reflexes bilaterally. He has a broad-based gait and impaired tandem gait. Fundoscopy shows bilateral swelling of the optic disc. There is esotropia of the left eye. Which of the following is the most likely diagnosis?", "answer": "Medulloblastoma\n\"", "options": {"A": "Optic glioma", "B": "Schwannoma", "C": "Hemangioblastoma", "D": "Meningioma", "E": "Medulloblastoma\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 82-year-old male visits his primary care physician for a check-up. He reports that he is in his usual state of health. His only new complaint is that he feels as if the room is spinning, which has affected his ability to live independently. He is currently on lisinopril, metformin, aspirin, warfarin, metoprolol, and simvastatin and says that he has been taking them as prescribed. On presentation, his temperature is 98.8°F (37°C), blood pressure is 150/93 mmHg, pulse is 82/min, and respirations are 12/min. On exam he has a left facial droop and his speech is slightly garbled. Eye exam reveals nystagmus with certain characteristics. The type of nystagmus seen in this patient would most likely also be seen in which of the following diseases?", "answer": "Multiple sclerosis", "options": {"A": "Aminoglycoside toxicity", "B": "Benign paroxysmal positional vertigo", "C": "Meniere disease", "D": "Multiple sclerosis", "E": "Vestibular neuritis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 56-year-old man comes to the physician because of a painless blistering rash on his hands, forearms, and face for 2 weeks. The rash is not itchy and seems to get worse in the sunlight. He has also noticed that his urine is darker than usual. His aunt and sister have a history of similar skin lesions. Examination of the skin shows multiple fluid-filled blisters and oozing erosions on the forearms, dorsal side of both hands, and forehead. There are areas of hyperpigmented scarring and patches of bald skin along the sides of the blisters. Which of the following is the most appropriate pharmacotherapy to treat this patient's condition?", "answer": "Hydroxychloroquine", "options": {"A": "Hemin", "B": "Prednisone", "C": "Fexofenadine", "D": "Acyclovir", "E": "Hydroxychloroquine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old man presents with a 2-day history of loose stools, anorexia, malaise, and abdominal pain. He describes the pain as moderate, cramping in character, and diffusely localized to the periumbilical region. His past medical history is unremarkable. He works as a wildlife photographer and, 1 week ago, he was in the Yucatan peninsula capturing the flora and fauna for a magazine. The vital signs include blood pressure 120/60 mm Hg, heart rate 90/min, respiratory rate 18/min, and body temperature 38.0°C (100.4°F). Physical examination is unremarkable. Which of the following is a characteristic of the microorganism most likely responsible for this patient’s symptoms?", "answer": "Overactivation of guanylate cyclase", "options": {"A": "Production of lecithinase", "B": "Inactivation of the 60S ribosomal subunit", "C": "Presynaptic vesicle dysregulation", "D": "Overactivation of guanylate cyclase", "E": "Disabling Gi alpha subunit"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A young Caucasian couple in their late twenties present for an infertility evaluation after trying to conceive over 2 years. On physical exam, the female appears healthy and states that she has regular menstrual cycles. The male partner is noted to have long extremities with wide hips, low muscle mass, gynecomastia, sparse facial or chest hair, and small, firm testes. Laboratory tests of the male partner reveal elevated serum LH and FSH and low testosterone levels. If cytogenetic tests were performed, which of the following would be seen in this male?", "answer": "Presence of a barr body", "options": {"A": "Presence of a barr body", "B": "Absence of a barr body", "C": "Absence of a second sex chromosome", "D": "Trisomy of chromosome 13", "E": "Trisomy of chromosome 18"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old female presents to the family physician with 3 weeks of headaches, sweating, and palpitations. Her BP was 160/125 mmHg, and a 24-hour urine test revealed elevated vanillylmandelic acid (VMA) and normetanephrine. Past medical history is notable for bilateral retinal hemangioblastomas, and family history is significant for three generations (patient, mother, and maternal grandfather) with similar symptoms. Genetic analysis revealed a mutation of a gene on chromosome 3p. Which of the following is the patient at risk of developing?", "answer": "Clear cell renal cell carcinoma", "options": {"A": "Clear cell renal cell carcinoma", "B": "Retinoblastoma", "C": "Osteosarcoma", "D": "Breast cancer", "E": "Ovarian cancer"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old female presents to a physician's office with complaints of having no energy for the last 2 weeks and sometimes feeling like staying home all day. She works for a technology start-up company and is attending graduate school part-time in the evening. She is very concerned about her health and tries to eat a balanced diet. She runs daily and takes yoga classes 3 times a week. She gets together with her friends every weekend and has continued to do so the last few weeks. Her schedule is quite hectic, and she is always on the go. There have been no changes in her sleep, appetite, or daily routine. She denies having flu-like symptoms, headaches, body aches, indigestion, weight loss, agitation, or restlessness. She admits to moderate drinking and marijuana use but has never smoked cigarettes. The medical history is unremarkable, and she takes no medications other than vitamin C for cold prevention. A friend suggested she take an herbal product containing ginseng and St. John's wort for her decreased energy levels. Her body mass index (BMI) is 22 kg/m2. The physical examination reveals no findings and lab testing shows the following:\nSodium 138 mEq/L\nPotassium 3.9 mEq/L\nChloride 101 mEq/L\nThyroid stimulating hormone 3.5 μU/mL\nHemoglobin (Hb%) 13.5 g/dL\nMean corpuscular hemoglobin (MCH) 31 pg\nMean corpuscular volume (MCV) 85 fL\nLeucocyte count 5000/mm3\nPlatelet count 250,000/mm3\nThe physician advises her to reduce the alcohol consumption and marijuana use. What else should she be advised?", "answer": "She is likely over-exerted and taking the herbal supplements has no proven medical benefit.", "options": {"A": "She should not take St. John's wort because of potential drug interactions with antidepressants.", "B": "She should start with the herbal product and return if her energy level does not improve in 2 weeks.", "C": "She should increase her diet so that she has more energy to go about her day.", "D": "She is likely over-exerted and taking the herbal supplements has no proven medical benefit.", "E": "She is taking excessive vitamin C and it is causing her low energy levels."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old man is brought to the emergency department by police officers due to inappropriate public behavior. He was at a pharmacy demanding to speak with the manager so he could discuss a business deal. Two weeks ago, he left his wife of 10 years and moved from another city in order to pursue his dreams of being an entrepreneur. He has not slept for more than 3-4 hours a night in the last 2 weeks. He has a history of bipolar disorder and diabetes. He has been hospitalized three times in the last year for mood instability. Current medications include lithium and insulin. Mental status examination shows accelerated speech with flight of ideas. His serum creatinine concentration is 2.5 mg/dL. Which of the following is the most appropriate next step in management with respect to his behavior?", "answer": "Valproic acid and quetiapine", "options": {"A": "Carbamazepine only", "B": "Clozapine only", "C": "Lithium and valproic acid", "D": "Valproic acid and quetiapine", "E": "Lithium and olanzapine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old woman undergoes diagnostic laparoscopy under general anesthesia for evaluation of chronic pelvic pain. Postoperatively, the patient requires prolonged intubation. Neostigmine is administered. Results of acceleromyography during train-of-four ulnar nerve stimulation are shown. Which of the following drugs is most likely to have been used preoperatively in this patient?", "answer": "Succinylcholine", "options": {"A": "Clonazepam", "B": "Ropivacaine", "C": "Rocuronium", "D": "Tizanidine", "E": "Succinylcholine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old woman is found to have multiple masses in her liver while performing abdominal ultrasonography for recurrent right upper quadrant abdominal pain. Biopsy of one of the masses discloses large plates of adenoma cells, which are larger than normal hepatocytes and contain glycogen and lipid. Regular septa, portal tracts, and bile ductules are absent. Which of the following is associated with this patient's condition?", "answer": "Oral contraceptive pills", "options": {"A": "Polyvinyl chloride", "B": "Carbon tetrachloride", "C": "Aflatoxin", "D": "Oral contraceptive pills", "E": "Smoking"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is following a 4-year-old boy with Duchenne muscular dystrophy. Western blot of skeletal muscle cells from this boy shows that the dystrophin protein is significantly smaller compared to the dystrophin protein of a healthy subject. Further evaluation shows that the boy's genetic mutation involves a sequence that normally encodes leucine. The corresponding mRNA codon has the sequence UUG. Which of the following codons is most likely present in this patient at the same position of the mRNA sequence?", "answer": "UAG", "options": {"A": "GUG", "B": "AUG", "C": "UAG", "D": "UUU", "E": "UCG"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 31-year-old woman gives birth to a boy in the labor and delivery ward of the local hospital. The child is immediately assessed and found to be crying vigorously. He is pink in appearance with blue extremities that appear to be flexed. Inducing some discomfort shows that both his arms and legs move slightly but remain largely flexed throughout. His pulse is found to be 128 beats per minute. What is the most likely APGAR score for this newborn at this time?", "answer": "7", "options": {"A": "5", "B": "6", "C": "7", "D": "8", "E": "9"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old man comes to his physician because of fatigue, night sweats, chills, and a 5-kg (11-lb) weight loss during the past 3 weeks. Eight years ago, he was treated for a hematological malignancy after biopsy of a neck swelling showed CD15+ and CD30+ cells. Physical examination shows conjunctival pallor and scattered petechiae. A peripheral blood smear is shown. Which of the following is the most likely explanation for this patient's current condition?", "answer": "Radiation-induced myeloid leukemia", "options": {"A": "Accelerated phase of chronic myeloid leukemia", "B": "Leukemic transformation of T-cell lymphoma", "C": "Richter transformation of small lymphocytic lymphoma", "D": "Leukemic transformation of myelodysplastic syndrome", "E": "Radiation-induced myeloid leukemia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old male presents to his primary care doctor complaining of abdominal pain. He reports a three-month history of intermittent burning pain localized to the epigastrium that worsens 2-3 hours after a meal. He attributes this pain to increased stress at his job. He is otherwise healthy and takes no medications. He does not smoke or drink alcohol. His temperature is 98.8°F (37.1°C), blood pressure is 130/85 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination reveals mild epigastric tenderness to palpation. A urease breath test is positive. Which of the following treatments is most appropriate first-line therapy for this patient?", "answer": "Amoxicillin, clarithromycin, and omeprazole", "options": {"A": "Octreotide", "B": "Sulfasalazine", "C": "Pantoprazole", "D": "Amoxicillin, clarithromycin, and omeprazole", "E": "Tetracycline, omeprazole, bismuth, and metronidazole"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 23-year-old woman comes to the physician because of a 1-week history of vaginal discharge. She has no pain or pruritus. She is sexually active with one male partner and uses condoms inconsistently. Pelvic examination shows a malodorous gray vaginal discharge. Microscopic examination of the vaginal discharge is shown. Which of the following is the most likely diagnosis?", "answer": "Bacterial vaginosis", "options": {"A": "Bacterial vaginosis", "B": "Chlamydia", "C": "Gonorrhea", "D": "Syphilis", "E": "Vaginal candidiasis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old man presents to the emergency department after he was assaulted and shot during a robbery. The patient was beaten with a baseball bat and has a bullet entry wound in his neck. He is currently complaining of diffuse pains but is able to speak. His voice sounds muffled, and he is requesting pain medications. An initial resuscitation is begun in the trauma bay. The patient's general appearance reveals ecchymosis throughout his body and minor scrapes and cuts, and possible multiple facial bone fractures. There is another bullet wound found in the left side of his back without an exit wound. Which of the following is the best next step in management?", "answer": "Orotracheal intubation", "options": {"A": "Administration of 100% oxygen", "B": "Cricothyroidotomy", "C": "Laryngeal mask", "D": "Nasotracheal intubation", "E": "Orotracheal intubation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old G3P3003 presents to her gynecologist for an annual visit. She complains of urinary incontinence when jogging since the birth of her last child three years ago. Her periods are regular every 30 days. The patient also has cramping that is worse before and during her period but always present at baseline. She describes a feeling of heaviness in her pelvis that is exacerbated by standing for several hours at her job as a cashier. The patient has had two spontaneous vaginal deliveries, one caesarean section, and currently uses condoms for contraception. She is obese and smokes a pack of cigarettes a day. Her mother died of breast cancer at age 69, and her aunt is undergoing treatment for endometrial cancer. The patient’s temperature is 98.6°F (37.0°C), pulse is 70/min, blood pressure is 142/81 mmHg, and respirations are 13/min. Pelvic exam is notable for a uterine fundus palpated just above the pubic symphysis and a boggy, smooth texture to the uterus. There is no tenderness or mass in the adnexa, and no uterosacral nodularity is noted. Which of the following is a classic pathological feature of this patient’s most likely diagnosis?", "answer": "Presence of endometrial tissue within the myometrium", "options": {"A": "Presence of endometrial tissue outside of the uterus", "B": "Presence of endometrial tissue within the myometrium", "C": "Focal hyperplasia of the myometrium", "D": "Nuclear atypia of endometrial cells", "E": "No pathognomonic findings expected"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 8-year-old girl is brought to the physician by her parents for a 10-month history of disturbing dreams and daytime sleepiness. She has difficulty falling asleep and says she sometimes sees ghosts just before falling asleep at night. She has had a 7-kg (15-lb) weight gain during this period despite no changes in appetite. She is alert and oriented, and neurologic examination is unremarkable. During physical examination, she spontaneously collapses after the physician drops a heavy book, producing a loud noise. She remains conscious after the collapse. Polysomnography with electroencephalogram is most likely to show which of the following?", "answer": "Rapid onset of beta waves", "options": {"A": "Periodic sharp waves", "B": "Slow spike-wave pattern", "C": "Rapid onset of beta waves", "D": "Decreased delta wave sleep duration", "E": "Diffuse slowing of waves"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old woman presents to the office after receiving a bone mineral density screening test result with a T score of -4.1 and a Z score of -3.8. She is diagnosed with osteoporosis. A review of her medical history reveals that she has taken estrogen-containing oral contraceptive pills from the age of 20 to 30. She suffered from heartburn from the age of 45 and took lansoprazole and ranitidine often for her symptoms. She also was on lithium for 2 years after being diagnosed with bipolar disorder at the age of 54. Last year she was diagnosed with congestive heart failure and was started on low dose hydrochlorothiazide. Which of her medications most likely contributed to the development of her osteoporosis?", "answer": "Lansoprazole", "options": {"A": "Lansoprazole", "B": "Hydrochlorothiazide", "C": "Ranitidine", "D": "Lithium", "E": "Estrogen"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old woman, gravida 3, para 2, at 41 weeks' gestation is admitted to the hospital in active labor. Her pregnancy has been uncomplicated. Both of her prior children were delivered by vaginal birth. She has a history of asthma. Current medications include iron and vitamin supplements. After a prolonged labor, she undergoes vaginal delivery. Shortly afterwards, she begins to have heavy vaginal bleeding with clots. Her temperature is 37.2°C (98.9°F), pulse is 90/min, respirations are 17/min, and blood pressure is 130/72 mm Hg. Examination shows a soft, enlarged, and boggy uterus on palpation. Laboratory studies show:\nHemoglobin 10.8 g/dL\nHematocrit 32.3%\nLeukocyte Count 9,000/mm3\nPlatelet Count 140,000/mm3\nProthrombin time 14 seconds\nPartial thromboplastin time 38 seconds\nHer bleeding continues despite bimanual uterine massage and administration of oxytocin. Which of the following is the most appropriate next step in management?\"", "answer": "Administer tranexamic acid", "options": {"A": "Perform hysterectomy", "B": "Perform curettage", "C": "Administer carboprost tromethamine", "D": "Tranfuse blood", "E": "Administer tranexamic acid"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-year-old male is brought to his pediatrician by his mother because of abdominal pain and blood in the stool. Scintigraphy reveals uptake in the right lower quadrant of the abdomen. Persistence of which of the following structures is the most likely cause of this patient's symptoms?", "answer": "Omphalomesenteric duct", "options": {"A": "Urachus", "B": "Omphalomesenteric duct", "C": "Paramesonephric duct", "D": "Allantois", "E": "Ureteric bud"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An otherwise healthy 25-year-old primigravid woman at 31 weeks' gestation comes to the physician with a 2-day history of epigastric pain and nausea that is worse at night. Three years ago, she was diagnosed with a peptic ulcer and was treated with a proton pump inhibitor and antibiotics. Medications include folic acid and a multivitamin. Her pulse is 92/min and blood pressure is 139/90 mm Hg. Pelvic examination shows a uterus consistent in size with a 31-week gestation. Laboratory studies show:\nHemoglobin 8.2 g/dL\nPlatelet count 87,000/mm3\nSerum\nTotal bilirubin 1.4 mg/dL\nAspartate aminotransferase 75 U/L\nLactate dehydrogenase 720 U/L\nUrine\npH 6.1\nProtein 2+\nWBC negative\nBacteria occasional\nNitrites negative\nWhich of the following best explains this patient's symptoms?\"", "answer": "Stretching of Glisson capsule", "options": {"A": "Bacterial invasion of the renal parenchyma", "B": "Break in gastric mucosal continuity", "C": "Acute inflammation of the pancreas", "D": "Inflammation of the gallbladder", "E": "Stretching of Glisson capsule"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-day-old newborn is brought to the emergency department by his mother due to a high fever that started last night. His mother says that he was born via an uneventful vaginal delivery at home at 38 weeks gestation and was doing fine up until yesterday when he became disinterested in breastfeeding and spit up several times. His temperature is 39.5°C (103.1°F), pulse is 155/min, respirations are 45/min, and O2 sats are 92% on room air. He is lethargic and minimally responsive to stimuli. While on his back, his head is quickly lifted towards his chest which causes his legs to flex. The mother had only a few prenatal care visits and none at the end of the pregnancy. What is the most likely source of this patients infection?", "answer": "During birth", "options": {"A": "Contaminated food", "B": "Tick bite", "C": "During birth", "D": "Mother’s roommate", "E": "Infection from surgery"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old man is brought to the emergency department due to right-sided facial and upper extremity weakness and aphasia. The patient was in his usual state of health until two hours prior to presentation, when he was eating breakfast with a friend and acutely developed the aforementioned symptoms. Medical history is unremarkable except for mild palpitations that occur during times of stress or when drinking coffee. Physical examination is consistent with the clinical presentation. Laboratory testing is unremarkable and a 12-lead electrocardiogram is normal. A non-contrast head CT and diffusion-weighted MRI shows no intracranial hemorrhage and an isolated superficial cerebral infarction. Transthoracic echocardiography with agitated saline mixed with air shows microbubbles in the left heart. There is a possible minor effusion surrounding the heart and the ejection fraction is within normal limits. Which of the following is most likely the cause of this patient's clinical presentation?", "answer": "Patent foramen ovale", "options": {"A": "Amyloid deposition within vessels", "B": "Aortic embolism", "C": "Berry aneurysm rupture", "D": "Cardiac arrhythmia", "E": "Patent foramen ovale"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old woman comes to the physician because of a 1-year history of intermittent episodes of shortness of breath, chest tightness, palpitation, dizziness, sweaty hands, and a feeling of impending doom. She says that her symptoms occur when she goes for a walk or waits in line for coffee. She reports that she no longer leaves the house by herself because she is afraid of being alone when her symptoms occur. She only goes out when her boyfriend accompanies her. She does not smoke or use illicit drugs. Within a few hours after each episode, physical examination and laboratory studies have shown no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Agoraphobia", "options": {"A": "Agoraphobia", "B": "Separation anxiety disorder", "C": "Panic disorder", "D": "Somatic symptom disorder", "E": "Generalized anxiety disorder"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old woman presents with chest pain for the last 20 minutes. She describes a ''squeezing'' sensation in the chest and can feel her heart ''racing''. Worried that she might be having a heart attack, she took aspirin before coming to the hospital. Five days ago, she says she had similar symptoms, but they resolved within 10 minutes. Her medical and family history is unremarkable. She denies any drug and alcohol use. Vital signs show a temperature of 37.0°C (98.6°F), a pulse of 110/min, a respiratory rate of 28/min, and blood pressure of 136/80 mm Hg. On physical examination, the patient appears fidgety and restless. An echocardiogram (ECG) shows sinus tachycardia but is otherwise normal. Which of the following is the next best step in treatment of this patient?", "answer": "Alprazolam", "options": {"A": "Alprazolam", "B": "Nitroglycerin", "C": "Propranolol", "D": "Buspirone", "E": "Sertraline"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 8-year-old boy is brought to the emergency department by his parents because of sudden onset of abdominal pain beginning an hour ago. The parents report that their son has also had an episode of dark urine earlier that morning. Three days ago, he was diagnosed with a urinary tract infection and was treated with trimethoprim-sulfamethoxazole. He emigrated from Liberia to the US with his family 3 years ago. There is no personal history of serious illness. His immunizations are up-to-date. Vital signs are within normal limits. Examination shows diffuse abdominal tenderness and scleral icterus. The spleen is palpated 1–2 cm below the left costal margin. Laboratory studies show:\nHemoglobin 10 g/dL\nMean corpuscular volume 90 μm3\nReticulocyte count 3%\nSerum\nBilirubin\nTotal 3 mg/dL\nDirect 0.5 mg/dL\nHaptoglobin 20 mg/dL (N=41–165 mg/dL)\nLactate dehydrogenase 160 U/L\nUrine\nBlood 3+\nProtein 1+\nRBC 2–3/hpf\nWBC 2–3/hpf\nWhich of the following is the most likely underlying cause of this patient's symptoms?\"", "answer": "Deficient glucose-6-phosphate dehydrogenase", "options": {"A": "Production of hemoglobin S", "B": "Cold agglutinins", "C": "Lead poisoning", "D": "Deficient glucose-6-phosphate dehydrogenase", "E": "Defective RBC membrane proteins"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old man comes to the emergency department because of a rash on his neck and back for the past 6 hours. He says that he first noticed some reddening of the skin on his back the previous evening, which turned into a blistering, red rash overnight. He went surfing the previous day and spent 5 hours at the beach. He reports having applied at least 1 oz of water-resistant SPF 30 sunscreen 30 minutes before leaving his home. His vitals are within normal limits. Physical examination shows erythema of the skin over the upper back and dorsum of the neck, with 3 vesicles filled with clear fluid. The affected area is edematous and tender to touch. Which of the following recommendations is most appropriate to prevent a recurrence of this patient's symptoms in the future?", "answer": "Reapply sunscreen after water exposure", "options": {"A": "Reapply sunscreen after water exposure", "B": "Apply sunscreen directly before getting into water", "C": "Use SPF 50 sunscreen", "D": "Apply at least 3 oz of sunscreen", "E": "Use waterproof sunscreen"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old woman comes to the physician because she has not had her period for 4 months. Menses had previously occurred at regular 28-day intervals with moderate flow. A home pregnancy test was negative. She also reports recurrent headaches and has noticed that when she goes to the movies she cannot see the outer edges of the screen without turning her head to each side. This patient's symptoms are most likely caused by abnormal growth of which of the following?", "answer": "Adenohypophysis", "options": {"A": "Astrocytes", "B": "Adenohypophysis", "C": "Arachnoid cap cells", "D": "Schwann cells", "E": "Pineal gland"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old man comes to the physician because of discoloration of the toenails. He has a history of peptic ulcer disease treated with pantoprazole. The physician prescribes oral itraconazole for a fungal infection and temporarily discontinues pantoprazole. Which of the following best describes the reason for discontinuing pantoprazole therapy?", "answer": "Decreased therapeutic effect of itraconazole due to decreased absorption", "options": {"A": "Increased toxicity of itraconazole due to cytochrome p450 induction", "B": "Decreased therapeutic effect of itraconazole due to cytochrome p450 inhibition", "C": "Decreased therapeutic effect of itraconazole due to decreased absorption", "D": "Decreased therapeutic effect of itraconazole due to cytochrome p450 induction", "E": "Increased toxicity of itraconazole due to decreased protein binding"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 15-year-old girl comes to the physician for a routine health maintenance examination. She recently became sexually active with her boyfriend and requests a prescription for an oral contraception. She lives with her parents. She has smoked half a pack of cigarettes daily for the past 2 years. Physical examination shows no abnormalities. A urine pregnancy test is negative. Which of the following is the most appropriate response?", "answer": "\"\"\"I would like to discuss the various contraceptive options that are available.\"\"\"", "options": {"A": "\"\"\"I would recommend performing a Pap smear, since you have become sexually active.\"\"\"", "B": "\"\"\"I would like to discuss the various contraceptive options that are available.\"\"\"", "C": "\"\"\"I would need your parent's permission before I can provide information about contraceptive therapy.\"\"\"", "D": "\"\"\"I cannot prescribe oral contraceptives if you are currently a smoker.\"\"\"", "E": "\"\"\"I would recommend a multiphasic combination of ethinyl estradiol and norgestimate.\"\"\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year-old woman comes to the physician for evaluation of a 5-month history of painful sexual intercourse. She also reports vaginal dryness and occasional spotting. She has no pain with urination. She has hypertension, type 2 diabetes mellitus, and hypercholesterolemia. Her last menstrual period was 8 months ago. She is sexually active with her husband and has two children. Current medications include ramipril, metformin, atorvastatin, and aspirin. Her temperature is 37°C (98.6°F), pulse is 85/min, and blood pressure is 140/82 mm Hg. Pelvic examination shows decreasing labial fat pad, receding pubic hair, and clear vaginal discharge. Which of the following is the most appropriate pharmacotherapy?", "answer": "Topical estrogen cream", "options": {"A": "Oral fluconazole", "B": "Topical nystatin", "C": "Topical estrogen cream", "D": "Oral metronidazole", "E": "Topical corticosteroids\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 36-year-old man is brought to the emergency department by his wife 20 minutes after having a seizure. Over the past 3 days, he has had a fever and worsening headaches. This morning, his wife noticed that he was irritable and demonstrated strange behavior; he put the back of his fork, the salt shaker, and the lid of the coffee can into his mouth. He has no history of serious illness and takes no medications. His temperature is 39°C (102.2°F), pulse is 88/min, and blood pressure is 118/76 mm Hg. Neurologic examination shows diffuse hyperreflexia and an extensor response to the plantar reflex on the right. A T2-weighted MRI of the brain shows edema and areas of hemorrhage in the left temporal lobe. Which of the following is most likely the primary mechanism of the development of edema in this patient?", "answer": "Breakdown of endothelial tight junctions", "options": {"A": "Release of vascular endothelial growth factor", "B": "Cellular retention of sodium", "C": "Breakdown of endothelial tight junctions", "D": "Degranulation of eosinophils", "E": "Increased hydrostatic pressure"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old woman presents to her primary care provider with blood in her urine and pain in her left flank. She has a 5-year history of polycystic ovarian syndrome managed with oral contraceptives and metformin. She is single and is not sexually active and denies a history of kidney stones or abdominal trauma. She has a 15-pack-year smoking history but denies the use of other substances. Her family history is significant for fatal lung cancer in her father at age 50, who also smoked, and recently diagnosed bladder cancer in her 45-year-old brother, who never smoked. On review of systems, she denies weight loss, fever, fatigue, paresthesia, increased pain with urination, or excessive bleeding or easy bruising. She is admitted to the hospital for a workup and observation. Her vital signs and physical exam are within normal limits. A urine pregnancy test is negative. PT is 14 sec and PTT is 20 sec. The rest of the laboratory results including von Willebrand factor activity and lupus anticoagulant panel are pending. A CT angiogram is ordered and is shown in the picture. What is indicated at this time to prevent a potential sequela of this patient’s condition?", "answer": "Administer heparin", "options": {"A": "Surgery", "B": "Administer heparin", "C": "Administer streptokinase", "D": "Thrombectomy", "E": "Administer warfarin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man is brought to the emergency department for crushing substernal chest pain at rest for the past 2 hours. The pain began gradually while he was having an argument with his wife and is now severe. He does not take any medications. He has smoked 1 pack of cigarettes daily for 35 years. He is diaphoretic. His temperature is 37.1°C (98.8°F), pulse is 110/min, respirations are 21/min, and blood pressure is 115/65 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. Cardiac examination shows an S4 gallop. The lungs are clear to auscultation. An ECG is shown. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Occlusion of the left anterior descending artery", "options": {"A": "Occlusion of the left anterior descending artery", "B": "Thromboembolism to the right interlobar pulmonary artery", "C": "Diffuse coronary vasospasm", "D": "Occlusion of the left circumflex artery", "E": "Tear in the intimal lining of the aorta"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old man presents to the office for a scheduled follow-up visit. He has had hypertension for the past 30 years and his current anti-hypertensive medications include lisinopril (40 mg/day) and hydrochlorothiazide (50 mg/day). He follows most of the lifestyle modifications recommended by his physician, but is concerned about his occasional occipital headaches in the morning. His blood pressure is 160/98 mm Hg. The physician adds another drug to his regimen that acts centrally as an α2-adrenergic agonist. Which of the following second messengers is involved in the mechanism of action of this new drug?", "answer": "Cyclic adenosine monophosphate", "options": {"A": "Cyclic adenosine monophosphate", "B": "Cyclic guanosine monophosphate", "C": "Inositol triphosphate", "D": "Diacylglycerol", "E": "Calcium ions"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 61-year-old woman comes to her physician for a burning sensation and numbness in her right hand for 4 weeks. The burning sensation is worse at night and is sometimes relieved by shaking the wrist. In the past week, she has noticed an exacerbation of her symptoms. She has rheumatoid arthritis and type 2 diabetes mellitus. Her medications include insulin, methotrexate, and naproxen. Her vital signs are within normal limits. Examination shows swan neck deformities of the fingers on both hands and multiple subcutaneous nodules over bilateral olecranon processes. There is tingling and numbness over the right thumb, index finger, and middle finger when the wrist is actively flexed. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next best step in management?", "answer": "Volar splinting", "options": {"A": "Physiotherapy", "B": "Initiate sulfasalazine therapy", "C": "Initiate azathioprine therapy", "D": "Volar splinting", "E": "Vitamin B6 supplementation\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old man with a history of chronic alcoholism presents to the emergency department with vomiting and diarrhea for 1 week. He states he feels weak and has had poor oral intake during this time. The patient is a current smoker and has presented many times to the emergency department for alcohol intoxication. His temperature is 97.5°F (36.4°C), blood pressure is 102/62 mmHg, pulse is 135/min, respirations are 25/min, and oxygen saturation is 99% on room air. On physical exam, he is found to have orthostatic hypotension and dry mucus membranes. Laboratory studies are ordered as seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 101 mEq/L\nK+: 3.9 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 9.8 mg/dL\n\nThe patient is given normal saline, oral potassium, dextrose, thiamine, and folic acid. The following day, the patient seems confused and complains of diffuse weakness and muscle/bone pain. An ECG and head CT are performed and are unremarkable. Which of the following is the most likely explanation for this patient's new symptoms?", "answer": "Hypophosphatemia", "options": {"A": "Hypocalcemia", "B": "Hypoglycemia", "C": "Hypomagnesemia", "D": "Hyponatremia", "E": "Hypophosphatemia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-year-old boy from a rural community is brought to the pediatrician after his parents noticed a white reflection in both of his eyes in recent pictures. Physical examination reveals bilateral leukocoria, nystagmus, and inflammation. When asked about family history of malignancy, the father of the child reports losing a brother to an eye tumor when they were children. With this in mind, which of the following processes are affected in this patient?", "answer": "Regulation of the G1-S transition", "options": {"A": "DNA mismatch repair", "B": "Nucleotide excision repair", "C": "Regulation of the G1-S transition", "D": "Base excision repair", "E": "Stem cell self-renewal"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A scientist is studying the excretion of a novel toxin X by the kidney in order to understand the dynamics of this new substance. He discovers that this new toxin X has a clearance that is half that of inulin in a particular patient. This patient's filtration fraction is 20% and his para-aminohippuric acid (PAH) dynamics are as follows:\n\nUrine volume: 100 mL/min\nUrine PAH concentration: 30 mg/mL\nPlasma PAH concentration: 5 mg/mL\n\nGiven these findings, what is the clearance of the novel toxin X?", "answer": "60 ml/min", "options": {"A": "60 ml/min", "B": "120 ml/min", "C": "300 ml/min", "D": "600 ml/min", "E": "1,500 ml/min"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old male with bipolar disorder comes to the physician because of erectile dysfunction for the past month. He cannot maintain an erection during intercourse and rarely wakes up with an erection. He says he is happy in his current relationship, but admits to decreased desire for sex and feeling embarrassed about his sexual performance. He sustained a lumbar vertebral injury one year ago following a motor vehicle accident. He takes medication for his bipolar disorder but does not remember the name. Physical examination shows testicular atrophy with otherwise normal genitalia. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Decreased testosterone levels", "options": {"A": "Decreased testosterone levels", "B": "Peyronie disease", "C": "Microvascular disease", "D": "Peripheral nerve injury", "E": "Psychologic stressors"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A scientist is designing experiments to better appreciate how the lung expands. He acquires two sets of cat lungs and fills one set with saline. He plots changes in the lungs' volume with respect to pressure as shown in Image A. The pressure-volume loop of the liquid-ventilated lung is different from the gas-ventilated lung because of what property?", "answer": "Increased compliance", "options": {"A": "Reduced airway resistance", "B": "Increased residual volume", "C": "More pronounced hysteresis", "D": "Increased compliance", "E": "Increased inspiratory pressure"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old man with a history of alcoholism is hospitalized with acute onset nausea and hematemesis. On admission, his vitals are as follows: blood pressure 110/70 mm Hg, heart rate 88/min, respiratory rate 16/min, and temperature 37.8℃ (100.0℉). Physical examination shows jaundice, palmar erythema, widespread spider angiomata, abdominal ascites, and visibly distended superficial epigastric veins. Abdominal ultrasound demonstrates portal vein obstruction caused by liver cirrhosis. Where in the liver would you find the earliest sign of fibrous deposition in this patient?", "answer": "Perisinusoidal space", "options": {"A": "Portal field", "B": "Lumen of sinusoids", "C": "Perisinusoidal space", "D": "Interlobular connective tissue", "E": "Lumen of bile ducts"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 54-year-old gardener with diabetes mellitus from the Northeast Jillin Province in China acquired a small scratch from a thorn while working in his flower garden. After 3 weeks, he noticed a small pink, painless bump at the site of a scratch. He was not concerned by the bump; however, additional linearly-distributed bumps that resembled boils began to appear 1 week later that were quite painful. When the changes took on the appearance of open sores that drained clear fluid without any evidence of healing (as shown on the image), he finally visited his physician. The physician referred to the gardener for a skin biopsy to confirm his working diagnosis and to start treatment as soon as possible. Which of the following is the most likely diagnosis for this patient?", "answer": "Sporotrichosis", "options": {"A": "Paracoccidioidomycosis", "B": "Blastomycosis", "C": "Cat scratch disease", "D": "Leishmaniasis", "E": "Sporotrichosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 5-year-old girl is brought to her pediatrician by her mother. The mother is concerned about a fine, red rash on her daughter’s limbs and easy bruising. The rash started about 1 week ago and has progressed. Past medical history is significant for a minor cold two weeks ago. The girl was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and is meeting all developmental milestones. Today, she has a heart rate of 90/min, respiratory rate of 22/min, blood pressure of 110/65 mm Hg, and temperature of 37.0°C (98.6°F). On physical exam, the girl has a petechial rash on her arms and legs. Additionally, there are several bruises on her shins and thighs. A CBC shows thrombocytopenia (20,000/mm3). Other parameters of the CBC are within expected range for her age. Prothrombin time (PT), partial thromboplastin time (PTT), and metabolic panels are all within reference range. What is the most likely blood disorder?", "answer": "Immune thrombocytopenic purpura (ITP)", "options": {"A": "Hemophilia B", "B": "Hemophilia A", "C": "Immune thrombocytopenic purpura (ITP)", "D": "Von Willebrand disease", "E": "Acute lymphoblastic leukemia (ALL)"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An otherwise healthy 45-year-old woman comes to the physician because of a 1-year history of episodic abdominal cramps, bloating, and flatulence. The symptoms worsen when she has pizza or ice cream and have become more frequent over the past 4 months. Lactose intolerance is suspected. Which of the following findings would most strongly support the diagnosis of lactose intolerance?", "answer": "Tall villi with focal collections of goblet cells", "options": {"A": "Partial villous atrophy with eosinophilic infiltrates", "B": "Periodic acid-Schiff-positive foamy macrophages", "C": "Tall villi with focal collections of goblet cells", "D": "Duodenal epithelium with dense staining for chromogranin A", "E": "Noncaseating granulomas with lymphoid aggregates"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man presents with an unremitting cough and swelling of the lower limbs for the past 2 weeks. He says he has had a chronic cough for years, however, he feels it is getting worse. He reports a 30-pack-year smoking history. Physical examination reveals mild central cyanosis and expiratory wheezes throughout the chest. Oxygen therapy is ordered immediately but, soon after administering it, his respiratory rate starts to slow down and he becomes drowsy. Dysfunction of which of the following receptors most likely led to this patient’s current condition?", "answer": "Central chemoreceptors", "options": {"A": "Airway stretch receptors", "B": "Central chemoreceptors", "C": "Peripheral chemoreceptors", "D": "Pleural pain receptors", "E": "Pulmonary stretch receptors"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 39-year-old woman comes to the physician because of a 5-month history of episodic retrosternal chest pain. She currently feels well. The pain is unrelated to exercise and does not radiate. The episodes typically last less than 15 minutes and lead to feelings of anxiety; resting relieves the pain. She has not had dyspnea or cough. She has hyperlipidemia treated with simvastatin. She does not smoke, drink alcohol, or use illicit drugs. Her temperature is 37°C (98.6°F), pulse is 104/min, respirations are 17/min, and blood pressure is 124/76 mm Hg. Cardiopulmonary examination shows no abnormalities. An ECG shows sinus tachycardia. Which of the following is the most appropriate next step in the evaluation of coronary artery disease in this patient?", "answer": "No further testing needed", "options": {"A": "Coronary CT angiogram", "B": "Nuclear exercise stress test", "C": "Troponin I measurement", "D": "No further testing needed", "E": "Dobutamine stress echocardiography"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old woman comes to the physician because of swelling of her legs for 2 months. She has noticed that her legs gradually swell up throughout the day. Two years ago, she underwent a coronary angioplasty. She has hypertension and coronary artery disease. She works as a waitress at a local diner. Her father died of liver cancer at the age of 61 years. She has smoked one pack of cigarettes daily for 31 years. She drinks one to two glasses of wine daily and occasionally more on weekends. Current medications include aspirin, metoprolol, and rosuvastatin. Vital signs are within normal limits. Examination shows 2+ pitting edema in the lower extremities. There are several dilated, tortuous veins over both calves. Multiple excoriation marks are noted over both ankles. Peripheral pulses are palpated bilaterally. The lungs are clear to auscultation. Cardiac examination shows no murmurs, gallops, or rubs. The abdomen is soft and nontender; there is no organomegaly. Which of the following is the most appropriate next step in management?", "answer": "Compression stockings", "options": {"A": "CT scan of abdomen and pelvis", "B": "Sclerotherapy", "C": "Compression stockings", "D": "Adjust antihypertensive medication", "E": "Abdominal ultrasound"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old woman with a history of paroxysmal atrial fibrillation comes to the physician for a follow-up visit. She feels well and wants to discuss pausing her only current medication, flecainide. Her pulse is 75/min and regular, blood pressure is 125/75 mm Hg. Physical examination shows no abnormalities. An ECG shows a PR interval of 180 ms, QRS time of 120 ms, and corrected QT interval of 440 ms. Which of the following ECG changes is most likely to be seen on cardiac stress testing in this patient?", "answer": "Prolonged QRS complex", "options": {"A": "Prolonged QTc interval", "B": "False-positive ST-segment depression", "C": "Shortened PR interval", "D": "Prolonged QRS complex", "E": "Decreased maximal heart rate"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old male is brought to the pediatrician for a low-grade fever. His mother states that he has had a waxing and waning fever for the past 6 days with temperatures ranging from 99.8°F (37.7°C) to 101.0°F (38.3°C). She reports that he had a similar episode three months ago. She also reports symmetric joint swelling in the child’s knees and wrists that has become increasingly noticeable over the past 8 weeks. He has not had a cough, difficulty breathing, or change in his bowel movements. The child was born at 40 weeks gestation. His height and weight are in the 45th and 40th percentiles, respectively. He takes no medications. His temperature is 100.1°F (37.8°C), blood pressure is 100/65 mmHg, pulse is 105/min, and respirations are 18/min. On examination, there is a non-pruritic, macular, salmon-colored truncal rash. Serological examination reveals the following:\n\nSerum:\nRheumatoid factor: Negative\nAnti-nuclear antibody: Negative\nAnti-double stranded DNA: Negative\nAnti-SSA: Negative\nAnti-SSB: Negative\nHuman leukocyte antigen B27: Positive\nErythrocyte sedimentation rate: 30 mm/h\n\nThis patient is most likely at increased risk of developing which of the following?", "answer": "Iridocyclitis", "options": {"A": "Iridocyclitis", "B": "Sacroiliitis", "C": "Scoliosis", "D": "Aortitis", "E": "Dactylitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old woman comes to the physician because of worsening chest pain on exertion. She was diagnosed with coronary artery disease and hyperlipidemia 3 months ago. At the time of diagnosis, she was able to walk for 15 minutes on the treadmill until the onset of chest pain. Her endurance had improved temporarily after she began medical treatment and she was able to walk her dog for 30 minutes daily without experiencing chest pain. Her current medications include daily aspirin, metoprolol, atorvastatin, and isosorbide dinitrate four times daily. Her pulse is 55/min and blood pressure is 115/78 mm Hg. Treadmill walking test shows an onset of chest pain after 18 minutes. Which of the following is most likely to improve this patient’s symptoms?", "answer": "Avoid isosorbide dinitrate at night", "options": {"A": "Increase dose of daily metoprolol", "B": "Avoid isosorbide dinitrate at night", "C": "Discontinue atorvastatin therapy", "D": "Add tadalafil to medication regimen", "E": "Decrease amount of aerobic exercise"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 63-year-old man presents to his primary care provider with colicky pain radiating to his left groin. The pain has been intermittent for several days. He has also been experiencing occasional burning pain in his hands and feet and frequent headaches. His past medical history is significant for an NSTEMI last year. He is currently taking atorvastatin and low dose aspirin. Today his temperature is 36.8°C (98.2°F), the heart rate is 103/min, the respiratory rate is 15/min, the blood pressure 135/85 mm Hg, and the oxygen saturation is 100% on room air. On physical exam, he appears gaunt and anxious. His heart is tachycardia with a regular rhythm and his lungs are clear to auscultation bilaterally. On abdominal exam he has hepatomegaly. A thorough blood analysis reveals a hemoglobin of 22 mg/dL and a significantly reduced EPO. Renal function and serum electrolytes are within normal limits. A urinalysis is positive for blood. A non-contrast CT shows a large kidney stone obstructing the left ureter. The patient’s pain is managed with acetaminophen and the stone passes with adequate hydration. It is sent to pathology for analysis. Additionally, a bone marrow biopsy is performed which reveals trilineage hematopoiesis and hypercellularity with a JAK2 mutation. Which medication would help prevent future episodes of nephrolithiasis?", "answer": "Allopurinol", "options": {"A": "Allopurinol", "B": "Probenecid", "C": "Thiazide", "D": "Hydroxyurea", "E": "Antihistamines"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old woman comes to the physician because of a 1-year history of nausea and chronic abdominal pain that is worse after eating. She has Hashimoto thyroiditis. She does not smoke or drink alcohol. A biopsy specimen of the corpus of the stomach shows destruction of the upper glandular layer of the gastric mucosa and G-cell hyperplasia. This patient is at greatest risk for which of the following conditions?", "answer": "Gastric adenocarcinoma", "options": {"A": "Gastric adenocarcinoma", "B": "Duodenal perforation", "C": "Curling ulcer", "D": "Aplastic anemia", "E": "Gastric MALT lymphoma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old female presents to the emergency department with squeezing right upper quadrant pain worse after eating. She has a history of a microcytic, hypochromic anemia with target cells. Physical exam shows severe tenderness to palpation in the right upper quadrant and a positive Murphy's sign. By genetic analysis a single point mutation is detected in the gene of interest. Despite this seemingly minor mutation, the protein encoded by this gene is found to be missing a group of 5 consecutive amino acids though the amino acids on either side of this sequence are preserved. This point mutation is most likely located in which of the following regions of the affected gene?", "answer": "Exon", "options": {"A": "Exon", "B": "Intron", "C": "Kozak consensus sequence", "D": "Polyadenylation sequence", "E": "Transcriptional promoter"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 59-year-old woman is referred to a neurologist for a hand tremor. Her symptoms began a few months prior to presentation and has progressively worsened. She noticed she was having difficulty drinking her coffee and writing in her notebook. The patient reports that her father also had a tremor but is unsure what type of tremor it was. She drinks 2-3 glasses of wine per week and only takes a multivitamin. Laboratory studies prior to seeing the neurologist demonstrated a normal basic metabolic panel and thyroid studies. On physical exam, there is a mid-amplitude 8 Hz frequency postural tremor of the right hand. The tremor is notable when the right hand is outstretched to the very end of finger-to-nose testing. Neurologic exam is otherwise normal. Which of the following is the best treatment option for this patient?", "answer": "Primidone", "options": {"A": "Alprazolam", "B": "Botulism-toxin injection", "C": "Deep brain stimulation", "D": "Levodopa-carbidopa", "E": "Primidone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 38-year-old man complains of a persistent high fever with chills, malaise, and diffuse abdominal pain for over a week. He recently returned from a trip to India. The fever began slowly and climbed its way up to 40.0°C (104.0°F) over the last 4 days. A physical exam reveals a white-coated tongue, enlarged spleen, and rose spots on the abdomen. A bone marrow aspirate was sent for culture which revealed motile gram-negative rods. Which of the following is true about the organism and the pathophysiology of this condition?", "answer": "It survives intracellularly within phagocytes of Peyer's patches.", "options": {"A": "It forms blue-green colonies with fruity odor.", "B": "It survives intracellularly within phagocytes of Peyer's patches.", "C": "Splenectomy may be necessary for carriers.", "D": "Incidence increases after cholecystectomy.", "E": "It releases a toxin which inactivates 60S ribosomes."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old girl is brought to the emergency department for evaluation of fever, poor feeding, and cough that began after she returned with her family from a trip to Mexico 1 week ago. Her temperature is 39°C (102.2°F), pulse is 120/min, respirations are 28/min, and blood pressure is 78/56 mm Hg. An x-ray of the chest shows a reticulonodular infiltrate throughout the lungs and a left-sided pleural effusion. A peripheral blood smear shows acid-fast bacilli. Which of the following abnormalities is most likely to be present?", "answer": "Decreased IFN-γ levels", "options": {"A": "Mutation in WAS gene", "B": "Mutations in common gamma chain gene", "C": "Decreased PTH levels", "D": "Absent B cells with normal T-cell count", "E": "Decreased IFN-γ levels"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old college student was playing basketball when he fell directly onto his left elbow. He had sudden, intense pain and was unable to move his elbow. He was taken immediately to the emergency room by his teammates. He has no prior history of trauma or any chronic medical conditions. His blood pressure is 128/84 mm Hg, the heart rate is 92/min, and the respiratory rate is 14/min. He is in moderate distress and is holding onto his left elbow. On physical examination, pinprick sensation is absent in the left 5th digit and the medial aspect of the left 4th digit. Which of the following is the most likely etiology of this patient’s condition?", "answer": "Ulnar neuropathy", "options": {"A": "Axillary neuropathy", "B": "Radial neuropathy", "C": "Musculocutaneous neuropathy", "D": "Median neuropathy", "E": "Ulnar neuropathy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 20-week-old infant is brought to an urgent care clinic by her mother because she has not been eating well for the past 2 days. The mother said her daughter has also been \"floppy\" since yesterday morning and has been unable to move or open her eyes since the afternoon of the same day. The child has recently started solid foods, like cereals sweetened with honey. There is no history of loose, watery stools. On examination, the child is lethargic with lax muscle tone. She does not have a fever or apparent respiratory distress. What is the most likely mode of transmission of the pathogen responsible for this patient’s condition?", "answer": "Contaminated food", "options": {"A": "Direct contact", "B": "Airborne transmission", "C": "Vector-borne disease", "D": "Contaminated food", "E": "Vertical transmission"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman presents with headaches. She says the headaches started about a month ago, and although initially, they were intermittent, over the past 2 weeks, they have progressively worsened. She describes the pain as severe, worse on the left than the right, and relieved somewhat by non-steroidal anti-inflammatory drugs (NSAIDs). The headaches are usually associated with nausea, vomiting, and photophobia. She denies any changes in vision, seizures, similar past symptoms, or focal neurologic deficits. Past medical history is significant for a posterior communicating artery aneurysm, status post-clipping 10 years ago. Her vital signs include: blood pressure 135/90 mm Hg, temperature 36.7°C (98.0°F), pulse 80/min, and respiratory rate 14/min. Her body mass index (BMI) is 36 kg/m2. On physical examination, the patient is alert and oriented. Her pupils are 3 mm on the right and mid-dilated on the left with subtle left-sided ptosis. Ophthalmic examination reveals a cup-to-disc ratio of 0.4 on the right and 0.5 on the left. The remainder of her cranial nerves are intact. She has 5/5 strength and 2+ reflexes in her upper extremities bilaterally and her left leg; her right leg has 3/5 strength with 1+ reflexes at the knee and ankle. The remainder of the physical examination is unremarkable. Which of the following findings in this patient most strongly suggests a further diagnostic workup?", "answer": "Right-sided weakness", "options": {"A": "Left eye findings", "B": "Right-sided weakness", "C": "Obesity", "D": "Age of onset", "E": "Photophobia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old woman presents to her physician for difficulty breathing. She states that this typically happens to her when she goes outside and improves with rest and staying indoors. Her symptoms are currently worse than usual. The patient has never seen a physician before and has no diagnosed past medical history. Her temperature is 99.5°F (37.5°C), blood pressure is 97/58 mmHg, pulse is 110/min, respirations are 25/min, and oxygen saturation is 88% on room air. Pulmonary function tests demonstrate a decreased inspiratory and expiratory flow rate. Which of the following is the best initial treatment for this patient?", "answer": "Epinephrine", "options": {"A": "Albuterol", "B": "Diphenhydramine", "C": "Epinephrine", "D": "Intubation", "E": "Prednisone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 44-year-old man presents to his psychiatrist for a follow-up appointment. He is currently being treated for schizophrenia. He states that he is doing well but has experienced some odd movement of his face recently. The patient's sister is with him and states that he has been more reclusive lately and holding what seems to be conversations despite nobody being in his room with him. She has not noticed improvement in his symptoms despite changes in his medications that the psychiatrist has made at the last 3 appointments. His temperature is 99.3°F (37.4°C), blood pressure is 157/88 mmHg, pulse is 90/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam is notable for rhythmic movements of the patient's mouth and tongue. Which of the following is a side effect of the next best step in management?", "answer": "Infection", "options": {"A": "Anxiolysis", "B": "Dry mouth and dry eyes", "C": "Infection", "D": "QT prolongation on EKG", "E": "Worsening of psychotic symptoms"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old man comes to the physician because of a 6-week history of fatigue and cramping abdominal pain. He works at a gun range. Examination shows pale conjunctivae and gingival hyperpigmentation. There is weakness when extending the left wrist against resistance. Further evaluation of this patient is most likely to show which of the following?", "answer": "Basophilic stippling of erythrocytes", "options": {"A": "Beta‑2 microglobulin in urine", "B": "White bands across the nails", "C": "Septal thickening on chest x-ray", "D": "Increased total iron binding capacity", "E": "Basophilic stippling of erythrocytes"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 67-year-old man comes to the clinic for establishment of care. He recently retired and moved to Florida with his wife. His past medical history includes hypertension, diabetes, chronic back pain, and hyperlipidemia. According to the patient, he takes lisinopril, metformin, atorvastatin, acetaminophen, and methadone. His previous doctor prescribed methadone for breakthrough pain as he has been having more severe pain episodes due to the recent move. He is currently out of his methadone and asks for a refill on the prescription. A physical examination is unremarkable except for mild lower extremity edema bilaterally and diffuse lower back pain upon palpation. What is the best initial step in the management of this patient?", "answer": "Assess the patient's pain medication history", "options": {"A": "Assess the patient's pain medication history", "B": "Encourage the patient to switch to duloxetine", "C": "Inform the patient that methadone is not the best option and do not prescribe", "D": "Prescribe a limited dose of methadone for breakthrough back pain", "E": "Refer the patient to a pain management clinic"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 75-year-old man presents to the physician because of bloody urine, which has occurred several times over the past month. He has no dysuria or flank pain. He has no history of serious illness, and he currently takes no medications. He is a 40-pack-year smoker. The vital signs are within normal limits. Physical exam shows no abnormalities except generalized lung wheezing. The laboratory test results are as follows:\nUrine:\nBlood 3+\nRBC > 100/hpf\nWBC 1–2/hpf\nRBC casts negative\nBacteria not seen\nCystoscopy reveals a solitary tumor in the bladder. Transurethral resection of the bladder tumor is performed. The tumor is 4 cm. Histologic evaluation shows invasion of the immediate epithelium of cells by a high-grade urothelial carcinoma without invasion of the underlying tissue or muscularis propria. Which of the following is the most appropriate next step in management?", "answer": "Intravesical Bacille Calmette-Guérin (BCG)", "options": {"A": "Bladder radiation", "B": "Bladder-sparing partial cystectomy", "C": "Intravesical Bacille Calmette-Guérin (BCG)", "D": "Systemic combination chemotherapy", "E": "No further treatment is needed at this time"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old man comes to the emergency room for severe left leg pain several hours after injuring himself on a gardening tool. His temperature is 39°C (102.2°F) and his pulse is 105/min. Physical examination of the left leg shows a small laceration on the ankle surrounded by dusky skin and overlying bullae extending to the posterior thigh. There is a crackling sound when the skin is palpated. Surgical exploration shows necrosis of the gastrocnemius muscles and surrounding tissues. Tissue culture shows anaerobic gram-positive rods and a double zone of hemolysis on blood agar. Which of the following best describes the mechanism of cellular damage caused by the responsible pathogen?", "answer": "Degradation of cell membranes by phospholipase", "options": {"A": "Lipopolysaccharide-induced complement and macrophage activation", "B": "Degradation of cell membranes by phospholipase", "C": "Increase of intracellular cAMP by adenylate cyclase", "D": "Inactivation of elongation factor by ribosyltransferase", "E": "Inhibition of neurotransmitter release by protease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old male presents to clinic today complaining that his medication has stopped working. He states despite being able to manage the side effects, a voice has returned again telling him to hurt his Mother. You prescribe him a drug which has shown improved efficacy in treating his disorder but requires frequent followup visits. One week later he returns with the following lab results: WBC : 2500 cells/mcL, Neutrophils : 55% and, Bands : 1%. What drug was this patient prescribed?", "answer": "Clozapine", "options": {"A": "Olanzapine", "B": "Halperidol", "C": "Chlorpromazine", "D": "Clozapine", "E": "Lurasidone"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old male presents to his primary care physician for fatigue, abdominal pain, diarrhea, and weight loss. He states that this issue has occurred throughout his life but seems to “flare up” on occasion. He states that his GI pain is relieved with defecation, and his stools are frequent, large, and particularly foul-smelling. The patient has a past medical history of an ACL tear, as well as a car accident that resulted in the patient needing a transfusion and epinephrine to treat transfusion anaphylaxis. His current medications include vitamin D and ibuprofen. He recently returned from a camping trip in the eastern United States. He states that on the trip they cooked packed meats over an open fire and obtained water from local streams. His temperature is 99.5°F (37.5°C), blood pressure is 120/77 mmHg, pulse is 70/min, respirations are 11/min, and oxygen saturation is 98% on room air. Physical exam reveals poor motor control and an ataxic gait on neurologic exam. Cardiac and pulmonary exams are within normal limits. Laboratory studies are ordered and return as below:\n\nHemoglobin: 9.0 g/dL\nHematocrit: 25%\nHaptoglobin: 12 mg/dL\nLeukocyte count: 7,500 cells/mm^3 with normal differential\nPlatelet count: 255,000/mm^3\n\nSerum:\nNa+: 140 mEq/L\nCl-: 102 mEq/L\nK+: 5.0 mEq/L\nHCO3-: 24 mEq/L\nBUN: 24 mg/dL\nGlucose: 82 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 9.0 mg/dL\nLDH: 457 U/L\nAST: 11 U/L\nALT: 11 U/L\n\nRadiography is ordered which reveals a stress fracture in the patient’s left tibia. Which of the following is the best confirmatory test for this patient’s condition?", "answer": "Bowel wall biopsy", "options": {"A": "Stool ELISA", "B": "Iron studies", "C": "Vitamin E level", "D": "Vitamin B12 and folate level", "E": "Bowel wall biopsy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-month-old boy has a malodorous umbilical discharge that developed shortly after umbilical cord separation. He was treated for omphalitis with 3 doses of antibiotics. The vital signs are as follows: blood pressure 70/40 mm Hg, heart rate 125/min, respiratory rate 34/min, and temperature 36.8℃ (98.2℉). On physical examination, he appears active and well-nourished. The skin in the periumbilical region is red and macerated. There is a slight green-yellow discharge from the umbilicus which resembles feces. The remnant of which structure is most likely causing the patient’s symptoms?", "answer": "Omphalomesenteric duct", "options": {"A": "Urachus", "B": "Right umbilical artery", "C": "Left umbilical artery", "D": "Omphalomesenteric duct", "E": "Umbilical vein"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old woman with a history of multiple sclerosis and recurrent urinary tract infections comes to the emergency department because of flank pain and fever. Her temperature is 38.8°C (101.8°F). Examination shows left-sided costovertebral angle tenderness. She is admitted to the hospital and started on intravenous vancomycin. Three days later, her symptoms have not improved. Urine culture shows growth of Enterococcus faecalis. Which of the following best describes the most likely mechanism of antibiotic resistance in this patient?", "answer": "Alteration of peptidoglycan synthesis", "options": {"A": "Production of beta-lactamase", "B": "Alteration of penicillin-binding proteins", "C": "Increased efflux across bacterial cell membranes", "D": "Alteration of peptidoglycan synthesis", "E": "Alteration of ribosomal targets"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old gravida 1-para-1 (G1P1) presents to the emergency department with severe lower abdominal pain that started several hours ago. She has had fevers, malaise, and nausea for the last 2 days. Her last menstrual period was 3 weeks ago. Her past medical history is insignificant. She has had 3 sexual partners in the past 1 month and uses oral contraception. The vital signs include temperature 38.8°C (101.8°F), and blood pressure 120/75 mm Hg. On physical examination, there is abdominal tenderness in the lower quadrants. Uterine and adnexal tenderness is also elicited. A urine test is negative for pregnancy. On speculum examination, the cervix is inflamed with motion tenderness and a yellow-white purulent discharge. Which of the following is the most likely diagnosis?", "answer": "Pelvic inflammatory disease", "options": {"A": "Vaginitis", "B": "Cervicitis", "C": "Pelvic inflammatory disease", "D": "Ruptured ectopic pregnancy", "E": "Urinary tract infection"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 54-year-old man presents to the emergency department with a severe diffuse abdominal pain, nausea, and vomiting. The patient states that the pain acute onset approximately 3 hours ago and has not improved. He denies any fever or chills. His last bowel movement was yesterday morning which was normal. The patient has a history of hypertension and infectious endocarditis 7 years ago. Current medications are hydrochlorothiazide and lisinopril. Patient denies any history of gastrointestinal disease although notes he frequently has abdominal discomfort after meals. Vital signs are as follows: blood pressure 150/90 mm Hg, heart rate 87/min, respiratory rate 22/min, and temperature of 37.4℃ (99.3℉). On physical examination, the patient is agitated and appears to be in significant pain. Lungs are clear to auscultation. The cardiac exam is significant for a 2/6 pansystolic grade murmur best heard at the apex and the presence of a pulse deficit. The abdomen is soft and nondistended, but there is tenderness to palpation in the periumbilical region. No rebound or guarding. Bowel sounds are present.\nLaboratory tests show the following results:\nRBC count 4.4 x 106/mm3\nHemoglobin 12.9 g/dL\nHematocrit 35%\nLeukocyte count 12,400/mm3\nPlatelet count 312,000/mm3\nSerum:  \nNa+ 140 mEq/L\nCl- 103 mEq/L\nK+ 4.4 mEq/L\nHCO3 20 mEq/L\nBase deficit -4\nBUN 11 mg/dL\nGlucose 97 mg/dL\nCreatinine 1.1 mg/dL\nCa2+ 10.7 mg/dL\nLactate 7.6 mmol/L\nAmylase 240 U/L\nStool guaiac negative\nEKG is significant for findings consistent with atrial fibrillation and left ventricular hypertrophy. Which of the following findings is most likely to be seen on this patient’s contrast CT of the abdomen?", "answer": "Lack of enhancement of the branches of the superior mesenteric artery", "options": {"A": "Dilated appendix with distended lumen and thickened wall", "B": "Numerous round and tubular structures communicating with the small intestine wall", "C": "Inner and outer layer enhancement of the bowel wall with non-enhancing middle layer", "D": "Lack of enhancement of the branches of the superior mesenteric artery", "E": "Loss of normal haustral markings of the large bowel"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 59-year-old woman presents to the family medicine clinic with a lump in her breast for the past 6 months. She states that she has been doing breast self-examinations once a month. She has a medical history significant for generalized anxiety disorder and systemic lupus erythematosus. She takes sertraline and hydroxychloroquine for her medical conditions. The heart rate is 102/min, and the rest of the vital signs are stable. On physical examination, the patient appears anxious and tired. Her lungs are clear to auscultation bilaterally. Capillary refill is 2 seconds. There is no axillary lymphadenopathy present. Palpation of the left breast reveals a 2 x 2 cm mass. What is the most appropriate next step given the history of the patient?", "answer": "Mammography", "options": {"A": "Referral to general surgery", "B": "Mammography", "C": "Lumpectomy", "D": "Biopsy of the mass", "E": "Continue breast self-examinations"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old woman, gravida 2, para 1, at 31 weeks gestation is admitted to the hospital because of regular contractions and pelvic pressure for 3 hours. Her pregnancy has been uncomplicated so far. She has attended many prenatal appointments and followed the physician's advice about screening for diseases, laboratory testing, diet, and exercise. She has no history of fluid leakage or bleeding. Her previous pregnancy was complicated by a preterm delivery at 34 weeks gestation. She smoked 1 pack of cigarettes daily for 10 years before pregnancy and has smoked 4 cigarettes daily during pregnancy. At the hospital, her temperature is 37.2°C (99.0°F), blood pressure is 108/60 mm Hg, pulse is 88/min, and respirations are 16/min. Cervical examination shows 2 cm dilation with intact membranes. Fetal examination shows no abnormalities. A cardiotocography shows a contraction amplitude of 220 montevideo units (MVU) in 10 minutes. Which of the following is the most appropriate pharmacotherapy at this time?", "answer": "Magnesium sulfate + Betamethasone", "options": {"A": "Betamethasone + Progesterone", "B": "Magnesium sulfate + Betamethasone", "C": "Oxytocin + Magnesium sulfate", "D": "Progesterone + Terbutaline", "E": "Terbutaline + Oxytocin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old man comes to the physician because of a sore throat and painful lesions in his mouth for the past few days. Six weeks ago, he underwent cardiac catheterization and stent implantation of the left anterior descending artery for treatment of acute myocardial infarction. Pharmacotherapy with dual antiplatelet medication was started. His temperature is 38.1°C (100.6°F). Oral examination shows several shallow ulcers on the buccal mucosa. Laboratory studies show:\nHematocrit 41.5%\nLeukocyte count 1,050/mm3\nSegmented neutrophils 35%\nPlatelet count 175,000/mm3\nWhich of the following drugs is most likely responsible for this patient's current condition?\"", "answer": "Ticlopidine", "options": {"A": "Abciximab", "B": "Ticlopidine", "C": "Apixaban", "D": "Enoxaparin", "E": "Aspirin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 31-year-old G3P2 who is at 24 weeks gestation presents for a regular check-up. She has no complaints, no concurrent diseases, and her previous pregnancies were vaginal deliveries with birth weights of 3100 g and 4180 g. The patient weighs 78 kg (172 lb) and is 164 cm (5 ft 5 in) in height. She has gained 10 kg (22 lb) during the current pregnancy. Her vital signs and physical examination are normal. The plasma glucose level is 190 mg/dL after a 75-g oral glucose load. Which of the listed factors contributes to the pathogenesis of the patient’s condition?", "answer": "Insulin antagonism of human placental lactogen", "options": {"A": "Insulin antagonism of human placental lactogen", "B": "Production of autoantibodies against pancreatic beta cells", "C": "Decrease in insulin sensitivity of maternal tissues caused by alpha-fetoprotein", "D": "Point mutations in the gene coding for insulin", "E": "Decrease in insulin gene expression"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old man comes to the physician for a follow-up examination. For the past year, he has had increasing calf cramping in both legs when walking, especially on an incline. He has hypertension. Since the last visit 6 months ago, he has been exercising on a treadmill four times a week; he has been walking until the pain starts and then continues after a short break. He has a history of hypertension controlled with enalapril. He had smoked 2 packs of cigarettes daily for 35 years but quit 5 months ago. His temperature is 37°C (98.6°F), pulse is 84/min, and blood pressure is 132/78 mm Hg. Cardiopulmonary examination shows no abnormalities. The calves and feet are pale. Femoral pulses can be palpated bilaterally; pedal pulses are absent. His ankle-brachial index is 0.6. Which of the following is the most appropriate next step in management?", "answer": "Clopidogrel and simvastatin", "options": {"A": "Clopidogrel and simvastatin", "B": "Operative vascular reconstruction", "C": "Percutaneous transluminal angioplasty and stenting", "D": "Vancomycin and piperacillin", "E": "Rest and orthotic braces"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 7-year-old boy is brought to the physician because his parents are concerned about his early sexual development. He has no history of serious illness and takes no medications. His brother was diagnosed with testicular cancer 5 years ago and underwent a radical orchiectomy. The patient is at the 85th percentile for height and 70th percentile for weight. Examination shows greasy facial skin. There is coarse axillary hair. Pubic hair development is at Tanner stage 3 and testicular development is at Tanner stage 2. The remainder of the examination shows no abnormalities. An x-ray of the wrist shows a bone age of 10 years. Basal serum luteinizing hormone and follicle-stimulating hormone are elevated. An MRI of the brain shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Leuprolide therapy", "options": {"A": "Radiation therapy", "B": "Cortisol supplementation", "C": "Leuprolide therapy", "D": "Testicular ultrasound", "E": "Observation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 41-year-old male presents to his primary care provider after seeing bright red blood in the toilet bowl after his last two bowel movements. He reports that the second time he also noticed some blood mixed with his stool. The patient denies abdominal pain and any changes in his stool habits. He notes a weight loss of eight pounds in the last two months. His past medical history is significant for an episode of pancreatitis two years ago for which he was hospitalized for several days. He drinks 2-3 beers on the weekend, and he has never smoked. He has no family history of colon cancer. His temperature is 97.6°F (36.4°C), blood pressure is 135/78 mmHg, pulse is 88/min, and respirations are 14/min. On physical exam, his abdomen is soft and nontender to palpation. Bowel sounds are present, and there is no hepatomegaly.\n\nWhich of the following is the best next step in diagnosis?", "answer": "Colonoscopy", "options": {"A": "Complete blood count", "B": "Abdominal CT", "C": "Colonoscopy", "D": "Barium enema", "E": "Anoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "You are interested in studying the etiology of heart failure reduced ejection fraction (HFrEF) and attempt to construct an appropriate design study. Specifically, you wish to look for potential causality between dietary glucose consumption and HFrEF. Which of the following study designs would allow you to assess for and determine this causality?", "answer": "Cohort study", "options": {"A": "Randomized controlled trial", "B": "Cohort study", "C": "Cross-sectional study", "D": "Case-control study", "E": "Case series"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 66-year-old man comes to the physician because of yellowish discoloration of his eyes and skin, abdominal discomfort, and generalized fatigue for the past 2 weeks. He has had dark urine and pale stools during this period. He has had a 10-kg (22-lb) weight loss since his last visit 6 months ago. He has hypertension. He has smoked one pack of cigarettes daily for 34 years. He drinks three to four beers over the weekends. His only medication is amlodipine. His temperature is 37.3°C (99.1°F), pulse is 89/min, respirations are 14/min, and blood pressure is 114/74 mm Hg. Examination shows jaundice of the sclera and skin and excoriation marks on his trunk and extremities. The lungs are clear to auscultation. The abdomen is soft and nontender. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12 g/dL\nLeukocyte count 5,000/mm3\nPlatelet count 400,000/mm3\nSerum\nUrea nitrogen 28 mg/dL\nCreatinine 1.2 mg/dL\nBilirubin\nTotal 7.0 mg/dL\nDirect 5.5 mg/dL\nAlkaline phosphatase 615 U/L\nAspartate aminotransferase (AST, GOT) 170 U/L\nAlanine aminotransferase (ALT, GPT) 310 U/L\nγ-Glutamyltransferase (GGT) 592 U/L (N = 5–50 U/L)\nAn ultrasound shows extrahepatic biliary dilation. A CT scan of the abdomen shows a 2.5-cm (1-in) mass in the head of the pancreas with no abdominal lymphadenopathy. The patient undergoes biliary stenting. Which of the following is the most appropriate next step in the management of this patient?\"", "answer": "Pancreaticoduodenectomy", "options": {"A": "Stereotactic radiation therapy", "B": "Gastroenterostomy", "C": "Pancreaticoduodenectomy", "D": "Gemcitabine and 5-fluorouracil therapy", "E": "Central pancreatectomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old man presents to the outpatient clinic for an annual employee health checkup. He does not have any complaints at the moment except for skin changes, as seen in the following image. He denies any history of trauma. His medical history is insignificant. His family history is negative for any skin disorders or autoimmune disease. He is a non-smoker and does not drink alcohol. Which of the following is the most likely mechanism for this presentation?", "answer": "Autoreactive T cells against melanocytes", "options": {"A": "Defect in melanoblast migration from the neural crest", "B": "Autoreactive T cells against melanocytes", "C": "Post-inflammatory hypopigmentation", "D": "Melanocytes unable to synthesize melanin", "E": "Invasion of the stratum corneum by Malassezia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old boy is brought to a psychotherapist for counseling because he was physically abused by his father. During the first therapy session, the patient recounts the numerous encounters that he had with his abuser. At the end of the session, the therapist, who lost her own son in a car accident when he was 15 years old, refuses to let the patient take the bus back alone to his custodial guardian's home. She offers to take him back in her own car instead, saying, “This way, I will rest assured that you have reached home safely”. The therapist's behavior can be best described as an instance of which of the following?", "answer": "Countertransference", "options": {"A": "Displacement", "B": "Isolation", "C": "Sublimation", "D": "Countertransference", "E": "Identification"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 8-year-old boy is brought to the physician by his parents because of repeated episodes of “daydreaming.” The mother reports that during these episodes the boy interrupts his current activity and just “stares into space.” She says that he sometimes also smacks his lips. The episodes typically last 1–2 minutes. Over the past 2 months, they have occurred 2–3 times per week. The episodes initially only occurred at school, but last week the patient had one while he was playing baseball with his father. When his father tried to talk to him, he did not seem to listen. After the episode, he was confused for 10 minutes and too tired to play. The patient has been healthy except for an episode of otitis media 1 year ago that was treated with amoxicillin. Vital signs are within normal limits. Physical and neurological examinations show no other abnormalities. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Temporal lobe spikes on EEG", "options": {"A": "Defiant behavior towards figures of authority", "B": "Impairment in communication and social interaction", "C": "Temporal lobe spikes on EEG", "D": "Conductive hearing loss on audiometry", "E": "Normal neurodevelopment"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 9-year-old boy is brought to the emergency room by his mother. She is concerned because her son’s face has been swollen over the past 2 days. Upon further questioning, the boy reports having darker urine without dysuria. The boy was seen by his pediatrician 10 days prior to presentation with a crusty yellow sore on his right upper lip that has since resolved. His medical history is notable for juvenile idiopathic arthritis. His temperature is 99°F (37.2°C), blood pressure is 140/90 mmHg, pulse is 95/min, and respirations are 18/min. On exam, he has mild periorbital edema. Serological findings are shown below:\n\nC2: Normal\nC3: Decreased\nC4: Normal\nCH50: Decreased\n\nAdditional workup is pending. This patient most likely has a condition caused by which of the following?", "answer": "Antigen-antibody complex deposition", "options": {"A": "Antigen-antibody complex deposition", "B": "Effector T cell sensitization and activation", "C": "IgE-mediated complement activation", "D": "IgM-mediated complement activation targeting antigens on the cellular surface", "E": "IgG-mediated complement activation targeting antigens on the cellular surface"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old pregnant woman with unknown medical history is admitted to the hospital at her 36th week of gestation with painful contractions. She received no proper prenatal care during the current pregnancy. On presentation, her vital signs are as follows: blood pressure is 110/60 mm Hg, heart rate is 102/min, respiratory rate is 23/min, and temperature is 37.0℃ (98.6℉). Fetal heart rate is 179/min. Pelvic examination shows a closed non-effaced cervix. During the examination, the patient experiences a strong contraction accompanied by a high-intensity pain after which contractions disappear. The fetal heart rate becomes 85/min and continues to decrease. The fetal head is now floating. Which of the following factors would most likely be present in the patient’s history?", "answer": "Fundal cesarean delivery", "options": {"A": "Postabortion metroendometritis", "B": "Intrauterine synechiae", "C": "Adenomyosis", "D": "Fundal cesarean delivery", "E": "Multiple vaginal births"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old woman presents to her family physician with pain on the front of her right knee. The pain started 2 months ago after she began training for a marathon, and it was gradual in onset and has slowly worsened. The pain increases with prolonged sitting and climbing stairs. She denies significant knee trauma. Her only medication is diclofenac sodium as needed for pain. Medical history is unremarkable. The vital signs include: temperature 36.9°C (98.4°F), blood pressure 100/70 mm Hg, and heart rate 78/min. Her body mass index is 26 kg/m2. The pain is reproduced by applying direct pressure to the right patella, and there is increased patellar laxity with medial and lateral displacement. The remainder of the examination is otherwise unremarkable. Which of the following is the most likely diagnosis?", "answer": "Patellofemoral pain syndrome", "options": {"A": "Patellar tendonitis", "B": "Iliotibial band syndrome", "C": "Prepatellar bursitis", "D": "Patellofemoral pain syndrome", "E": "Osgood-Schlatter's disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old Caucasian male presents to your office complaining of black, tarry stool. Which of the following possible causes of this patient's presentation is LEAST associated with the development of carcinoma?", "answer": "Duodenal ulcer", "options": {"A": "Barrett's esophagus", "B": "H. pylori infection", "C": "Adenomatous polyp", "D": "Gastric ulcer", "E": "Duodenal ulcer"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 30-year-old man with a BMI of 33.7 kg/m2 presents with severe pain in his right toe that began this morning. He had a few beers last night at a friend’s party but otherwise has had no recent dietary changes. On examination, the right toe appears swollen, warm, red, and tender to touch. Joint aspiration is performed. What will examination of the fluid most likely reveal?", "answer": "Needle-shaped, negatively birefringent crystals on polarized light", "options": {"A": "Increased glucose", "B": "Needle-shaped, negatively birefringent crystals on polarized light", "C": "Rhomboid-shaped, positively birefringent crystals on polarized light", "D": "Gram-negative diplococci", "E": "Anti-CCP antibodies"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 38-year-old male presents to his primary care physician complaining of increasing shortness of breath over the past 2 months. He reports experiencing an extended illness of several weeks as a child that required him to miss school. He is unsure but believes it involved a sore throat followed by a fever and joint pains. He does not recall seeing a physician or receiving treatment for this. Today, on physical examination, cardiac auscultation reveals an opening snap after the second heart sound followed by a diastolic murmur. A follow-up echocardiogram is conducted. Which of the following best explains the pathophysiology of this patient's condition?", "answer": "Epitope homology", "options": {"A": "Annular calcification", "B": "Epitope homology", "C": "Myocardial ischemia", "D": "Atherosclerosis", "E": "Congenital heart defect"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old woman presents to the emergency department with an episode of nausea and severe unrelenting right upper abdominal pain. She had a cholecystectomy for gallstones a year earlier and has since experienced frequent recurrences of abdominal pain, most often after a meal. Her past medical history is otherwise unremarkable and she only takes medications for her pain when it becomes intolerable. Her physical exam is normal except for an intense abdominal pain upon deep palpation of her right upper quadrant. Her laboratory values are unremarkable with the exception of a mildly elevated alkaline phosphatase, amylase, and lipase. Her abdominal ultrasound shows a slightly enlarged common bile duct at 8 mm in diameter (N = up to 6 mm) and a normal pancreatic duct. The patient is referred to a gastroenterology service for an ERCP (endoscopic retrograde cholangiopancreatography) to stent her common bile duct. During the procedure the sphincter at the entrance to the duct is constricted. Which statement best describes the regulation of the function of the sphincter which is hampering the cannulation of the pancreatic duct in this patient?", "answer": "A hormone released by the I cells of the duodenum in the presence of fatty acids is the most effective cause of relaxation.", "options": {"A": "A hormone released by the I cells of the duodenum in the presence of fatty acids is the most effective cause of relaxation.", "B": "The sphincter is contracted between meals.", "C": "Sphincter relaxation is enhanced via stimulation of opioid receptors.", "D": "A hormone released by the M cells of the duodenum is the most effective cause of relaxation.", "E": "Regulation of function of the sphincter of Oddi does not involve neural inputs."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old man comes to the emergency department because of a 1-day history of black, tarry stools. He has also had upper abdominal pain that occurs immediately after eating and a 4.4-kg (9.7-lb) weight loss in the past 6 months. He has no history of major medical illness but drinks 3 beers daily. His only medication is acetaminophen. He is a financial consultant and travels often for work. Physical examination shows pallor and mild epigastric pain. Esophagogastroduodenoscopy shows a bleeding 15-mm ulcer in the antrum of the stomach. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Helicobacter pylori infection", "options": {"A": "Age above 40 years", "B": "Alcohol consumption", "C": "Acetaminophen use", "D": "Work-related stress", "E": "Helicobacter pylori infection"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old Nigerian woman arrived 2 days ago to the US to visit her adult children from Nigeria. She is now brought to an urgent care center by her daughter for leg pain. Her right leg has been painful for 24 hours and is now causing her to limp. She denies any fevers, chills, or sweats and does not remember injuring her leg. She tells you she takes medications for hypertension and diabetes and occasionally for exertional chest pain. She has not had any recent chest pain. The right leg is swollen and tender. Flexion of the right ankle causes a worsening of the pain. Doppler ultrasonography reveals a large clot in a deep vein. Which of the following is the most appropriate course of action?", "answer": "Initiation of heparin followed by bridge to warfarin", "options": {"A": "Serologic tests for hypercoagulability", "B": "Initiation of warfarin", "C": "Initiation of heparin", "D": "Treatment with tissue plasminogen activator", "E": "Initiation of heparin followed by bridge to warfarin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old G1P0 woman presents to an obstetrician for her first prenatal visit. She has been pregnant for about 10 weeks and is concerned about how pregnancy will affect her health. Specifically, she is afraid that her complicated medical history will be adversely affected by her pregnancy. Her past medical history is significant for mild polycythemia, obesity hypoventilation syndrome, easy bleeding, multiple sclerosis, and aortic regurgitation. Which of these disorders is most likely to increase in severity during the course of the pregnancy?", "answer": "Heart murmur", "options": {"A": "Easy bleeding", "B": "Heart murmur", "C": "Hypoventilation", "D": "Multiple sclerosis", "E": "Polycythemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year-old man presents to a physician with repeated episodes of joint pain and fever for the last 3 months. The pain is present in the knee joints and small joints of the hands bilaterally. He recorded his temperature at home which never increased above 37.8°C (100.0°F). The medical history is significant for an acute myocardial infarction 1 year ago, with sustained ventricular tachycardia as a complication, for which he has been taking procainamide. The vital signs are as follows: pulse 88/min, blood pressure 134/88 mm Hg, respiratory rate 13/min, and temperature 37.2°C (99.0°F). On physical examination, he has mild joint swelling. A radiologic evaluation of the involved joints does not suggest osteoarthritis or rheumatoid arthritis. Based on the laboratory evaluation, the physician suspects that the joint pain and fever may be due to the use of procainamide. Which of the following serologic finding is most likely to be present in this patient?", "answer": "Presence of anti-histone antibodies", "options": {"A": "Presence of anti-dsDNA antibodies", "B": "Decreased serum C4 level", "C": "Decreased serum C3 level", "D": "Presence of anti-histone antibodies", "E": "Presence of anti-Sm antibodies"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old man is brought to the emergency department by his wife 30 minutes after the onset of nausea, sweating, and palpitations. On the way to the hospital, he had an episode of non-bloody vomiting and intravenous fluid resuscitation has been started. He has no history of similar symptoms. For the past 2 weeks, he has been trying to lose weight and has adjusted his diet and activity level. He eats a low-carb diet and runs 3 times a week for exercise; he came home from a training session 3 hours ago. He was diagnosed with type 2 diabetes mellitus 2 years ago that is controlled with basal insulin and metformin. He appears anxious. His pulse is 105/min and blood pressure is 118/78 mm Hg. He is confused and oriented only to person. Examination shows diaphoresis and pallor. A fingerstick blood glucose concentration is 35 mg/dL. Shortly after, the patient loses consciousness and starts shaking. Which of the following is the most appropriate next step in management?", "answer": "Administer intravenous dextrose", "options": {"A": "Administer intravenous dextrose", "B": "Administer intravenous phenoxybenzamine", "C": "Administer intravenous lorazepam", "D": "Administer intramuscular glucagon", "E": "Obtain an EEG"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 6-year-old girl is brought to the physician by her parents because of concern that she is the shortest in her class. She has always been short for her age, but she is upset now that her classmates have begun teasing her for her height. She has no history of serious illness and takes no medications. She is 109 cm (3 ft 7 in) tall (10th percentile) and weighs 20 kg (45 lb) (50th percentile). Her blood pressure is 140/80 mm Hg. Vital signs are otherwise within normal limits. Physical examination shows a low-set hairline and a high-arched palate. Breast development is Tanner stage 1 and the nipples are widely spaced. Extremities are well perfused with strong peripheral pulses. Her hands are moderately edematous. This patient is at increased risk of developing which of the following complications?", "answer": "Aortic insufficiency", "options": {"A": "Renal cell carcinoma", "B": "Precocious puberty", "C": "Aortic insufficiency", "D": "Ectopia lentis", "E": "Acute lymphoblastic leukemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 62-year-old man presents to the ED complaining of severe eye pain that started a few hours ago. The patient reports that he fell asleep while watching TV on the couch and woke up with right-sided eye pain and blurry vision. His wife drove him to the emergency room. His wife reports that since they arrived the patient has also been complaining of intense nausea. The patient denies fever, headache, or visual floaters. He has a history of hypertension, hyperlipidemia, type II diabetes mellitus, and osteoarthritis. He takes aspirin, lisinopril, metformin, atorvastatin, and over-the-counter ibuprofen. His temperature is 99°F (37.2°C), blood pressure is 135/82 mmHg, and pulse is 78/min. On physical examination, the right eye is firm with an injected conjunctiva and a mildly cloudy cornea. The pupil is dilated at 6 mm and is non-reactive to light. Ocular eye movements are intact. Vision is 20/200 in the right eye and 20/40 in the left eye. The left eye exam is unremarkable. Which of the following is the most appropriate initial treatment?", "answer": "Intravenous acetazolamide", "options": {"A": "Intravenous acetazolamide", "B": "Iridotomy", "C": "Retinal photocoagulation", "D": "Topical epinephrine", "E": "Topical prednisolone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old boy presents to the office with his mother. She states that her son seems weak and unwilling to walk. He only learned how to walk recently after a very notable delay. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all verbal and social milestones but he has a great deal of trouble with gross and fine motor skills. Past medical history is noncontributory. He takes a multivitamin every day. The mother states that some boys on her side of the family have had similar symptoms and worries that her son might have the same condition. Today, the boy’s vital signs include: blood pressure 110/65 mm Hg, heart rate 90/min, respiratory rate 22/min, and temperature 37.0°C (98.6°F). On physical exam, the boy appears well developed and pleasant. He sits and listens and follows direction. His heart has a regular rate and rhythm and his lungs are clear to auscultation bilaterally. He struggles to get up to a standing position after sitting on the floor. A genetic study is performed that reveals a significant deletion in the gene that codes for dystrophin. Which of the following is the most likely diagnosis?", "answer": "Duchenne muscular dystrophy", "options": {"A": "Duchenne muscular dystrophy", "B": "Becker muscular dystrophy", "C": "Limb-girdle muscular dystrophy", "D": "Myotonic muscular dystrophy", "E": "Emery-Dreifuss muscular dystrophy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old woman is brought to the emergency room after an apparent suicide attempt. She is unable to provide a history, but her husband reports that he found her at home severely confused and agitated. She reportedly mentioned swallowing several of her pills but was unable to provide additional details. Her husband reports that she has a history of Crohn disease, major depressive disorder, social anxiety disorder, and prior heroin and alcohol abuse. She has not taken heroin or alcohol for 5 years and attends Alcoholics Anonymous and Narcotics Anonymous regularly. She takes multiple medications but he is unable to recount which medications she takes and they are not in the electronic medical record. Her temperature is 103.9°F (39.9°C), blood pressure is 160/95 mmHg, pulse is 125/min, and respirations are 28/min. On exam, she appears agitated, diaphoretic, and is responding to internal stimuli. She has clonus in her bilateral feet. Pupils are 3 mm and reactive to light. Patellar and Achilles reflexes are 3+ bilaterally. She is given alprazolam for her agitation but she remains severely agitated and confused. Which of the following medications should be given to this patient?", "answer": "Cyproheptadine", "options": {"A": "Ammonium chloride", "B": "Cyproheptadine", "C": "Flumazenil", "D": "N-acetylcysteine", "E": "Naloxone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 21-year-old man was involved in a motor vehicle accident and died. At autopsy, the patient demonstrated abnormally increased mobility at the neck. A section of cervical spinal cord at C6 was removed and processed into slides. Which of the following gross anatomic features is most likely true of this spinal cord level?", "answer": "Cuneate and gracilis fasciculi are present", "options": {"A": "Prominent lateral horns", "B": "Least amount of white matter", "C": "Absence of gray matter enlargement", "D": "Involvement with parasympathetic nervous system", "E": "Cuneate and gracilis fasciculi are present"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A rapid diagnostic test has been developed amid a major avian influenza outbreak in Asia. The outbreak has reached epidemic levels with a very high attack rate. Epidemiologists are hoping to use the rapid diagnostic test to identify all exposed individuals and curb the rapid spread of disease by isolating patients with any evidence of exposure to the virus. The epidemiologists compared rapid diagnostic test results to seropositivity of viral antigen via PCR in 200 patients. The findings are represented in the following table:\nTest result PCR-confirmed avian influenza No avian influenza\nPositive rapid diagnostic test 95 2\nNegative rapid diagnostic test 5 98\nWhich of the following characteristics of the rapid diagnostic test would be most useful for curbing the spread of the virus via containment?\"", "answer": "Sensitivity of 95/100", "options": {"A": "Sensitivity of 98/100", "B": "Specificity of 95/100", "C": "Positive predictive value of 95/97", "D": "Specificity of 98/100", "E": "Sensitivity of 95/100"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 69-year-old woman comes to the emergency department because of a 2-day history of cough and dyspnea. The cough is productive of small amounts of green phlegm. She has stage IV colon cancer and chronic obstructive pulmonary disease. Her medications include 5-fluorouracil, leucovorin, a fluticasone-salmeterol inhaler, and a tiotropium bromide inhaler. Her temperature is 39°C (102.2°F), pulse is 107/min, respirations are 31/min, and blood pressure is 89/68 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 87%. Pulmonary examination shows diffuse crackles and rhonchi. An x-ray of the chest shows a left upper-lobe infiltrate of the lung. Two sets of blood cultures are obtained. Endotracheal aspirate Gram stain shows gram-negative rods that are oxidase-positive. Two large bore cannulas are inserted and intravenous fluids are administered. Which of the following is the most appropriate pharmacotherapy?", "answer": "Cefepime and levofloxacin", "options": {"A": "Ertapenem and gentamicin", "B": "Clarithromycin and amoxicillin-clavulanate", "C": "Cefepime and levofloxacin", "D": "Vancomycin", "E": "Colistin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 31-year-old man presents to the office with complaints of multiple episodes of blood in his urine as well as coughing of blood for the past 3 days. He also reports a decrease in urinary frequency, and denies pain with urination. No previous similar symptoms or significant past medical history is noted. There is no history of bleeding disorders in his family. His vitals include a blood pressure of 142/88 mm Hg, a pulse of 87/min, a temperature of 36.8°C (98.2°F), and a respiratory rate of 11/min. On physical examination, chest auscultation reveals normal vesicular breath sounds. Abdominal exam is normal. The laboratory results are as follows:\nComplete blood count\nHemoglobin 12 g/dL\nRBC 4.9 x 106 cells/µL\nHematocrit 48%\nTotal leukocyte count 6,800 cells/µL\nNeutrophils 70%\nLymphocyte 25%\nMonocytes 4%\nEosinophil 1%\nBasophils 0%\nPlatelets 200,000 cells/µL\n    Urine examination\npH 6.2\nColor dark brown\nRBC 18–20/HPF\nWBC 3–4/HPF\nProtein 1+\nCast RBC casts\nGlucose absent\nCrystal none\nKetone absent\nNitrite absent \n24 hours urine protein excretion  1.3 g\nA renal biopsy under light microscopy shows a crescent formation composed of fibrin and macrophages. Which of the following best describes the indirect immunofluorescence finding in this condition?", "answer": "Linear immunofluorescence deposits of IgG and C3 along GBM", "options": {"A": "Mesangial deposition of IgA often with C3", "B": "Granular sub-endothelial deposits", "C": "Linear immunofluorescence deposits of IgG and C3 along GBM", "D": "Granular lumpy bumpy appearance along GBM and mesangium", "E": "Negative immunofluorescence"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 13-year-old girl is evaluated by an orthopedic surgeon for knee pain. She thinks that the pain started after she fell while playing basketball during gym class 4 months ago. At the time she was evaluated and diagnosed with a muscle strain and told to rest and ice the joint. Since then the pain has gotten progressively worse and interferes with her ability to participate in gym. She has otherwise been healthy and does not take any medications. On physical exam, she is found to have mild swelling and erythema over the left knee. The joint is found to have an intact full range of motion as well as tenderness to palpation on both the medial and lateral femoral condyles. Radiograph shows a crescent-shaped radiolucency in the subchondral bone of the femur with the remainder of the radiograph being normal. Which of the following disorders is most likely responsible for this patient's symptoms?", "answer": "Osteochondritis dissecans", "options": {"A": "Anterior cruciate ligament injury", "B": "Ewing sarcoma", "C": "Osgood-Schlatter disease", "D": "Osteochondritis dissecans", "E": "Osteogenesis imperfecta"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "E. coli has the ability to regulate its enzymes to break down various sources of energy when available. It prevents waste by the use of the lac operon, which encodes a polycistronic transcript. At a low concentration of glucose and absence of lactose, which of the following occurs?", "answer": "Increased cAMP levels result in binding to the catabolite activator protein", "options": {"A": "Increased allolactose levels bind to the repressor", "B": "Increased cAMP levels result in binding to the catabolite activator protein", "C": "Decreased cAMP levels result in poor binding to the catabolite activator protein", "D": "Trascription of the lac Z, Y, and A genes increase", "E": "Repressor releases from lac operator"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 1-month-old female presents with her parents to the pediatrician for a well visit. Her mother reports that the patient has been exclusively breastfed since birth. The patient feeds for 30 minutes 6-7 times per day, urinates 8-10 times per day, and passes 4-5 loose, “seedy” yellow stools per day. The patient sleeps for about ten hours at night and takes 3-4 naps of 2-3 hours duration each. Her mother is concerned that the patient cries significantly more than her two older children. She reports that the patient cries for about 20-30 minutes up to four times per day, usually just before feeds. The crying also seems to be worse in the early evening, and the patient’s mother reports that it is difficult to console the patient. The patient’s parents have tried swaddling the patient and rocking her in their arms, but she only seems to calm down when in the infant swing. The patient’s height and weight are in the 60th and 70th percentiles, respectively, which is consistent with her growth curves. Her temperature is 97.4°F (36.3°C), blood pressure is 74/52 mmHg, pulse is 138/min, and respirations are 24/min. On physical exam, the patient appears comfortable in her mother’s arms. Her anterior fontanelle is soft and flat, and her eye and ear exams are unremarkable. Her abdomen is soft, non-tender, and non-distended. She is able to track to the midline.\n\nThis patient is most likely to have which of the following conditions?", "answer": "Normal infant crying", "options": {"A": "Constipation", "B": "Gastroesophageal reflux disease", "C": "Infantile colic", "D": "Milk protein allergy", "E": "Normal infant crying"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A newborn girl develops poor feeding and respiratory distress 4 days after delivery. She was born at a gestational age of 29 weeks. The child was born via cesarean section due to reduced movement and a non-reassuring fetal heart tracing. APGAR scores were 6 and 8 at 1 and 5 minutes, respectively. Her vitals are as follows:\n  Patient values Normal newborn values\nBlood pressure 67/39 mm Hg 64/41 mm Hg\nHeart rate 160/min 120–160/min\nRespiratory rate 60/min 40–60 min\nThe newborn appears uncomfortable with a rapid respiratory rate and mild cyanosis of the fingers and toes. She also has nasal flaring and grunting. Her legs appear edematous. A chest X-ray shows evidence of congestive heart failure. An echocardiogram shows enlargement of the left atrium and ventricle. What medication would be appropriate to treat this infants condition?", "answer": "Indomethacin", "options": {"A": "Indomethacin", "B": "Methadone", "C": "Caffeine", "D": "Alprostadil", "E": "Dexamethasone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old, previously healthy woman is admitted to the hospital with abdominal pain and bloody diarrhea. She reports consuming undercooked beef a day before the onset of her symptoms. Her medical history is unremarkable. Vital signs include: blood pressure 100/70 mm Hg, pulse rate 70/min, respiratory rate 16/min, and temperature 36.6℃ (97.9℉). Physical examination shows paleness, face and leg edema, and abdominal tenderness in the lower right quadrant. Laboratory investigation shows the following findings:\nErythrocytes 3 x 106/mm3\nHemoglobin 9.4 g/dL\nHematocrit 0.45 (45%)\nCorrected reticulocyte count  5.5%\nPlatelet count 18,000/mm3\nLeukocytes 11,750/mm3\nTotal bilirubin 2.33 mg/dL (39.8 µmol/L)\nDirect bilirubin 0.2 mg/dL (3.4 µmol/L)\nSerum creatinine 4.5 mg/dL (397.8 µmol/L)\nBlood urea nitrogen 35.4 mg/dL (12.6 mmol/L)\nE. coli O157: H7 was identified in the patient’s stool. Which toxin is likely responsible for her symptoms?", "answer": "Verotoxin", "options": {"A": "α-hemolysin", "B": "Shiga toxin", "C": "Verotoxin", "D": "Enterotoxin type B", "E": "Erythrogenic toxin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old woman, gravida 2, para 1, at 35 weeks' gestation comes to the emergency department because of an episode of vaginal bleeding that morning. The bleeding has subsided. She has had no prenatal care. Her previous child was delivered with a caesarean section because of a breech presentation. Her temperature is 37.1°C (98.8°F), pulse is 88/min, respirations are 14/min, and blood pressure is 125/85 mm Hg. The abdomen is nontender and the size of the uterus is consistent with a 35-week gestation. No contractions are felt. The fetal heart rate is 145/min. Her hemoglobin concentration is 12 g/dL, leukocyte count is 13,000/mm3, and platelet count is 350,000/mm3. Transvaginal ultrasound shows that the placenta covers the internal os. Which of the following is the most appropriate next step in management?", "answer": "Schedule elective cesarean delivery", "options": {"A": "Perform emergency cesarean delivery", "B": "Administer oxytocin to induce labor", "C": "Observation only", "D": "Perform bimanual pelvic examination", "E": "Schedule elective cesarean delivery"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old man presents to the emergency department with his family because of abdominal pain, excessive urination, and drowsiness since the day before. He has had type 1 diabetes mellitus for 2 years. He ran out of insulin 2 days ago. The vital signs at admission include: temperature 36.8°C (98.2°F), blood pressure 102/69 mm Hg, and pulse 121/min. On physical examination, he is lethargic and his breathing is rapid and deep. There is a mild generalized abdominal tenderness without rebound tenderness or guarding. His serum glucose is 480 mg/dL. Arterial blood gas of this patient will most likely show which of the following?", "answer": "↓ pH, ↓ bicarbonate and ↑ anion gap", "options": {"A": "↑ pH, ↑ bicarbonate, and normal pCO2", "B": "↑ pH, normal bicarbonate and ↓ pCO2", "C": "↓ pH, normal bicarbonate and ↑ pCO2", "D": "↓ pH, ↓ bicarbonate and ↑ anion gap", "E": "↓ pH, ↓ bicarbonate and normal anion gap"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old woman comes to the physician because of right flank pain that started 3 days following a procedure. Her vital signs are within normal limits. Physical examination shows right costovertebral angle tenderness. An intravenous pyelogram shows a dilated renal pelvis and ureter on the right with a lack of contrast proximal to the ureterovesical junction. This patient most likely recently underwent which of the following procedures?", "answer": "Hysterectomy", "options": {"A": "Cesarean delivery", "B": "Hysterectomy", "C": "Foley catheter insertion", "D": "Inguinal hernia repair", "E": "Appendectomy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-month-old is referred to a pediatric immunologist by his pediatrician for further workup of recurrent sinopulmonary infections which have not abated despite adequate treatment. During the workup flow cytometry demonstrates a decrease in normal CD40L cells. Based on these findings, the immunologist decides to pursue a further workup and obtains immunoglobulin levels. Which of the following immunoglobulin profiles is most likely to be observed in this patient?", "answer": "Increased IgM; Decreased IgG, IgA, IgE", "options": {"A": "Increased IgE; Decreased IgG, IgM", "B": "Decreased IgE, IgM, IgA, IgG", "C": "Increased IgE, IgA; Decreased IgM", "D": "Increased IgE", "E": "Increased IgM; Decreased IgG, IgA, IgE"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 78-year-old woman comes to her family physician for an annual health maintenance examination. Her husband, who worked as an art collector and curator, recently passed away. To express her gratitude for the longstanding medical care of her husband, she offers the physician and his staff a framed painting from her husband's art collection. Which of the following is the most appropriate reaction by the physician?", "answer": "Politely decline and explain that he cannot accept valuable gifts from his patients.", "options": {"A": "Accept the gift to maintain a positive patient-physician relationship but decline any further gifts.", "B": "Politely decline and explain that he cannot accept valuable gifts from his patients.", "C": "Accept the gift and donate the painting to a local museum.", "D": "Politely decline and explain that he cannot accept gifts that belonged to her late husband.", "E": "Accept the gift and assure the patient that he will take good care of her."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old female presents to her primary care physician after noting a lump in her left breast. She reports finding it two months prior to presentation and feels that it has not grown significantly in that time. She denies nipple discharge or tenderness. On exam, she is noted to have a 3-4 cm, rubbery mass in the left breast. Biopsy shows invasive ductal carcinoma that is estrogen receptor positive. Her oncologist prescribes tamoxifen. All of the following are effects of tamoxifen EXCEPT:", "answer": "Decreased risk of endometrial cancer", "options": {"A": "Decreased risk of endometrial cancer", "B": "Increased risk of deep vein thrombosis", "C": "Induction of menopausal symptoms", "D": "Decreased risk of osteoporosis", "E": "Increased risk of ocular toxicity"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old man presents to his physician with the complaint of a painful toe joint on his right foot. He states that the onset of pain came on suddenly, waking him up in the middle of the night. On physical exam, the metatarsophalangeal (MTP) joint of the big toe is swollen and erythematous. The physician obtains information regarding his past medical history and current medications. Which of the following medications would have the potential to exacerbate this patient’s condition?", "answer": "Hydrochlorothiazide", "options": {"A": "Allopurinol", "B": "Colchicine", "C": "Hydrochlorothiazide", "D": "Indomethacin", "E": "Methotrexate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 75 year-old gentleman presents to his general practitioner. He is currently being treated for hypertension and is on a multi-drug regimen. His current blood pressure is 180/100. The physician would like to begin treatment with minoxidil or hydralazine. Which of the following side effects is associated with administration of these drugs?", "answer": "Reflex tachycardia", "options": {"A": "Persistent cough", "B": "Systemic volume loss", "C": "Fetal renal toxicity", "D": "Reflex tachycardia", "E": "Cyanosis in extremities"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 44-year-old woman presents to the emergency department with severe, fluctuating right upper quadrant abdominal pain. The pain was initially a 4/10 but has increased recently to a 6/10 prompting her to come in. The patient has a past medical history of type II diabetes mellitus, depression, anxiety, and irritable bowel syndrome. Her current medications include metformin, glyburide, escitalopram and psyllium husks. On exam you note an obese woman with pain upon palpation of the right upper quadrant. The patient's vital signs are a pulse of 95/min, blood pressure of 135/90 mmHg, respirations of 15/min and 98% saturation on room air. Initial labs are sent off and the results are below:\n\nNa+: 140 mEq/L\nK+: 4.0 mEq/L\nCl-: 100 mEq/L\nHCO3-: 24 mEq/L\nAST: 100 U/L\nALT: 110 U/L\nAmylase: 30 U/L\nAlkaline phosphatase: 125 U/L\nBilirubin\nTotal: 2.5 mg/dL\nDirect: 1.8 mg/dL\n\nThe patient is sent for a right upper quadrant ultrasound demonstrating an absence of stones, no pericholecystic fluid, a normal gallbladder contour and no abnormalities noted in the common bile duct. MRCP with secretin infusion is performed demonstrating patent biliary and pancreatic ductal systems. Her lab values and clinical presentation remain unchanged 24 hours later. Which of the following is the best next step in management?", "answer": "ERCP with manometry", "options": {"A": "Elective cholecystectomy", "B": "Laparoscopy", "C": "ERCP with manometry", "D": "Analgesics and await resolution of symptoms", "E": "MRI of the abdomen"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old child presents to the pediatrician with mental retardation, ataxia, and inappropriate laughter. The parents of the child decide to have the family undergo genetic testing to determine what the cause may be. The results came back and all three had no mutations that would have caused this constellation of symptoms in the child. Karyotyping was performed as well and showed no deletions, insertions, or gene translocations. Based on the symptoms, the child was diagnosed with Angelman syndrome. Which of the following genetic terms could best describe the mechanism for the disorder in the child?", "answer": "Uniparental disomy", "options": {"A": "Codominance", "B": "Incomplete penetrance", "C": "Anticipation", "D": "Uniparental disomy", "E": "Variable expressivity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old man is brought to his neurologist by his wife for bizarre behavior. On several occasions over the last several days, he had started to complain about ‘bunnies, tigers, and emus’ in the living room. The patient has a history of multiple sclerosis and was last seen by his primary neurologist 2 weeks ago for complaints of new left upper extremity weakness. On physical exam, his temperature is 37.0°C (98.6°F), the heart rate is 70/min, the blood pressure is 126/78 mm Hg, the respiratory rate is 16/min, and the oxygen saturation is 98% on room air. The exam is disrupted by the patient’s repeated comments about various animals in the exam room. His neurologic exam is unchanged from his neurologist's last documented exam. The basic metabolic panel is as follows:\nNa+ 138 mEq/L\nK+ 3.9 mEq/L\nCl- 101 mEq/L\nHCO3- 24 mEq/L\nBUN 10 mg/dL\nCr 0.6 mg/dL\nGlucose 356 mg/dL\nWhich of the following is the most likely etiology of this patient's presentation?", "answer": "Medication side effect", "options": {"A": "Medication side effect", "B": "Metabolic abnormality", "C": "Primary psychiatric illness", "D": "Progression of neurologic disease", "E": "Recreational drug intoxication"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man presents to the physician with limb weakness over the last 24 hours. He is an otherwise healthy man with no significant past medical history. On physical examination, his vital signs are stable. On neurological examination, there is decreased strength in the muscles of all 4 extremities, and the deep tendon reflexes are depressed. A detailed laboratory evaluation shows that he has generalized decreased neuronal excitability due to an electrolyte imbalance. Which of the following electrolyte imbalances is most likely to be present in the man?", "answer": "Acute hypercalcemia", "options": {"A": "Acute hyperkalemia", "B": "Acute hypercalcemia", "C": "Acute hypomagnesemia", "D": "Acute hypernatremia", "E": "Acute hypochloremia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-year-old boy comes to the physician for the evaluation of intermittent blood-tinged urine for several months. Four months ago, he had an episode of fever and sore throat that resolved without treatment after 5 days. During the past 2 years, he has also had recurrent episodes of swelling of his face and feet. 5 years ago, he was diagnosed with mild bilateral sensorineural hearing loss. His brother died of a progressive kidney disease at the age of 23. The patient appears pale. His temperature is 37°C (98.6°F), pulse is 70/min, and blood pressure is 145/85 mm Hg. Slit lamp examination shows a conical protrusion of both lenses. Laboratory studies show a hemoglobin concentration of 11 g/dL, urea nitrogen concentration of 40 mg/dL, and creatinine concentration of 2.4 mg/dL. Urinalysis shows:\nBlood 2+\nProtein 1+\nRBC 5–7/hpf\nRBC casts rare\nWhich of the following is the most likely underlying cause of this patient's symptoms?\"", "answer": "Defective type IV collagen", "options": {"A": "IgA deposits", "B": "Type II hypersensitivity reaction", "C": "WT1 gene mutation", "D": "Defective type IV collagen", "E": "Autosomal-recessive kidney disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to the emergency department because of high-grade fever and lethargy for 4 days. He has had a severe headache for 3 days and 2 episodes of non-bilious vomiting. He has sickle cell disease. His only medication is hydroxyurea. His mother has refused vaccinations and antibiotics in the past because of their possible side effects. He appears ill. His temperature is 40.1°C (104.2°F), pulse is 131/min, and blood pressure is 92/50 mm Hg. Examination shows nuchal rigidity. Kernig and Brudzinski signs are present. A lumbar puncture is performed. Analysis of the cerebrospinal fluid (CSF) shows a decreased glucose concentration, increased protein concentration, and numerous segmented neutrophils. A Gram stain of the CSF shows gram-negative coccobacilli. This patient is at greatest risk for which of the following complications?", "answer": "Hearing loss", "options": {"A": "Hearing loss", "B": "Adrenal insufficiency", "C": "Brain abscess", "D": "Cerebral palsy", "E": "Communicating hydrocephalus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old boy is admitted to the emergency department with a history of fatigue, fever of 40.0°C (104.0°F), sore throat, and enlarged cervical lymph nodes. On physical examination, his spleen and liver are not palpable. A complete blood count is remarkable for atypical reactive T cells. An examination of his tonsils is shown in the image below. Which of the following statements is true about the condition of this patient?", "answer": "The infectious organism can become latent in B cells.", "options": {"A": "The infectious organism is heterophile-negative.", "B": "The infectious organism causes Cutaneous T-cell lymphoma.", "C": "The infectious organism can become latent in B cells.", "D": "Splenomegaly is a rare finding.", "E": "The infectious organism can become latent in macrophages."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 54-year-old man was brought to the emergency room due to acute onset of slurred speech while at work, after which he lost consciousness. The patient’s wife says this occurred approximately 30 minutes ago. Past medical history is significant for poorly controlled hypertension and type 2 diabetes mellitus. His blood pressure is 90/50 mm Hg, respiratory rate is 12/min, and heart rate is 48/min. The patient passes away shortly after arriving at the hospital. At autopsy, bilateral wedge-shaped strips of necrosis are seen in this patient’s brain just below the medial temporal lobes. Which of the following is the most likely location of these necrotic cells?", "answer": "Hippocampus", "options": {"A": "Hippocampus", "B": "Caudate nucleus", "C": "Cortex or cerebral hemisphere", "D": "Frontal lobe", "E": "Substantia nigra"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old man is brought to the emergency department 40 minutes after falling off a 10-foot ladder. He has severe pain and swelling of his right ankle and is unable to walk. He did not lose consciousness after the fall. He has no nausea. He appears uncomfortable. His temperature is 37°C (98.6°F), pulse is 98/min, respirations are 16/min, and blood pressure is 110/80 mm Hg. He is alert and oriented to person, place, and time. Examination shows multiple abrasions over both lower extremities. There is swelling and tenderness of the right ankle; range of motion is limited by pain. The remainder of the examination shows no abnormalities. An x-ray of the ankle shows an extra-articular calcaneal fracture. Intravenous analgesia is administered. Which of the following is the most appropriate next step in the management of this patient?", "answer": "X-ray of the spine", "options": {"A": "MRI of the right ankle", "B": "Long leg cast", "C": "Open reduction and internal fixation", "D": "X-ray of the spine", "E": "Broad-spectrum antibiotic therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A G1P0 mother gives birth to a male infant at 37 weeks gestation. She received adequate prenatal care and took all her prenatal vitamins. She is otherwise healthy and takes no medications. On the 1 month checkup, examination revealed a machine-like murmur heard at the left sternal border. Which of the following medications would be most appropriate to give the infant to address the murmur?", "answer": "Indomethacin", "options": {"A": "Bosentan", "B": "Digoxin", "C": "Indomethacin", "D": "Prostaglandin E1", "E": "Prostaglandin E2"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old woman is brought to the physician by her father because of strange behavior for the past 6 months. The father reports that his daughter has increasingly isolated herself in college and received poor grades. She has told her father that aliens are trying to infiltrate her mind and that she has to continuously listen to the radio to monitor these activities. She appears anxious. Her vital signs are within normal limits. Physical examination shows no abnormalities. Neurologic examination shows no focal findings. Mental status examination shows psychomotor agitation. She says: “I can describe how the aliens chase me except for my car which is parked in the garage. You know, the sky is beautiful today. Why does my mother have a cat?” Which of the following best describes this patient's thought process?", "answer": "Loose associations", "options": {"A": "Circumstantial speech", "B": "Thought-blocking", "C": "Loose associations", "D": "Flight of ideas", "E": "Clang associations"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man presents to urgent care for weakness and weight loss. He states for the past several months he has felt progressively weaker and has lost 25 pounds. The patient also endorses intermittent abdominal pain. The patient has not seen a physician in 30 years and recalls being current on most of his vaccinations. He says that a few years ago, he went to the emergency department due to abdominal pain and was found to have increased liver enzymes due to excessive alcohol use and incidental gallstones. The patient has a 50 pack-year smoking history. His temperature is 99.5°F (37.5°C), blood pressure is 161/108 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 95% on room air. Physical exam reveals an emaciated man. The patient has a negative Murphy's sign and his abdomen is non-tender. Cardiopulmonary exam is within normal limits. Which of the following is the next best step in management?", "answer": "CT scan of the abdomen", "options": {"A": "CT scan of the abdomen", "B": "CT scan of the liver", "C": "HIDA scan", "D": "Right upper quadrant ultrasound", "E": "Smoking cessation advice and primary care follow up"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 69-year-old woman is brought to the emergency department by her husband because of a 1-day history of fever, shortness of breath, dizziness, and cough productive of purulent sputum. Six days ago, she developed malaise, headache, sore throat, and myalgias that improved initially. Her temperature is 39.3°C (102.7°F) and blood pressure is 84/56 mm Hg. Examination shows an erythematous, desquamating rash of the distal extremities. A sputum culture grows gram-positive, coagulase-positive cocci in clusters. The most likely causal organism of this patient's current symptoms produces a virulence factor with which of the following functions?", "answer": "Binding of Fc domain of immunoglobulin G", "options": {"A": "Degradation of membranous phospholipids", "B": "Binding of Fc domain of immunoglobulin G", "C": "Overstimulation of guanylate cyclase", "D": "Destruction of immunoglobulin A", "E": "Inactivation of elongation factor 2"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A man is brought into the emergency department by police. The patient was found somnolent in the park and did not respond to questioning. The patient's past medical history is unknown, and he is poorly kempt. The patient's personal belongings include prescription medications and illicit substances such as alprazolam, diazepam, marijuana, cocaine, alcohol, acetaminophen, and a baggie containing an unknown powder. His temperature is 97.0°F (36.1°C), blood pressure is 117/58 mmHg, pulse is 80/min, respirations are 9/min, and oxygen saturation is 91% on room air. Physical exam reveals pupils that do not respond to light bilaterally, and a somnolent patient who only withdraws his limbs to pain. Which of the following is the best next step in management?", "answer": "Naloxone", "options": {"A": "Flumazenil", "B": "Intubation", "C": "N-acetylcysteine", "D": "Naloxone", "E": "Supportive therapy, thiamine, and dextrose"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator inoculates three different broths with one colony-forming unit of Escherichia coli. Broth A contains 100 μmol of lactose, broth B contains 100 μmol of glucose, and broth C contains both 100 μmol of lactose and 100 μmol of glucose. After 24 hours, the amounts of lactose, galactose, and glucose in the three broths are measured. The results of the experiment are shown:\nLactose Galactose Glucose\nBroth A 43 μmol 11 μmol 9 μmol\nBroth B 0 μmol 0 μmol 39 μmol\nBroth C 94 μmol 1 μmol 66 μmol\nThe observed results are most likely due to which of the following properties of broth A compared to broth C?\"", "answer": "Increased activity of adenylate cyclase", "options": {"A": "Increased activity of glycosylases", "B": "Decreased activity of catabolite activator protein", "C": "Decreased production of α-galactosidase A", "D": "Increased activity of adenylate cyclase", "E": "Binding of repressor protein to operator protein"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman presents with a complaint of pain in the metacarpophalangeal joints and proximal interphalangeal joints bilaterally. Serology showed positive anti-CCP antibodies. She has been prescribed infliximab for control of her condition. Which of the following needs to be tested before starting treatment in this patient?", "answer": "PPD skin test", "options": {"A": "Uric acid levels", "B": "PPD skin test", "C": "Complete blood counts", "D": "G6PD levels", "E": "Ophthalmic examination"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old African American G1P0 mother gives birth to a male infant at 33 weeks' gestation. The mother had no prenatal care and took no prenatal vitamins. The child’s postnatal period was complicated by neonatal sepsis due to group B Streptococcus. He required a two week stay in the neonatal intensive care unit to receive antibiotics, cardiopulmonary support, and intravenous nutrition. He eventually recovered and was discharged. At a normal follow-up visit to the pediatrician’s office one month later, the mother asks about the child’s skin color and hair color. On examination, the child has white hair and diffusely pale skin. The child’s irises appear translucent. Further questioning of the mother reveals that there is a distant family history of blindness. This child most likely has a defect in an enzyme involved in the metabolism of which of the following molecules?", "answer": "DOPA", "options": {"A": "DOPA", "B": "Phenylalanine", "C": "Leucine", "D": "Homocystieine", "E": "Homogentisic acid"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A pathologist performed an autopsy on an 18-month-old infant boy who died of pneumonia. Clinical notes revealed the infant had repeated respiratory infections that started after he was weaned off of breast-milk. Laboratory investigation revealed hypogammaglobulinemia and an absence of B-cells. T-cell levels were normal. Histological evaluation of an axillary lymph node revealed an absence of germinal centers. Which of the following is the mode of inheritance of the disorder that afflicted this infant?", "answer": "X-linked recessive", "options": {"A": "Autosomal recessive", "B": "Autosomal dominant", "C": "X-linked recessive", "D": "X-linked dominant", "E": "Mitochondrial inheritance"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old man is brought to the emergency department for the evaluation of intermittent bloody vomiting for the past 2 hours. He has had similar episodes during the last 6 months that usually stop spontaneously within an hour. The patient is not aware of any medical problems. He has smoked one pack of cigarettes daily for 30 years but quit 10 years ago. He drinks half a liter of vodka daily. He appears pale and diaphoretic. His temperature is 37.3°C (99.1°F), pulse is 100/min, respirations are 20/min, and blood pressure is 105/68 mm Hg. Cardiac examination shows no murmurs, rubs, or gallops. There is increased abdominal girth. On percussion of the abdomen, the fluid-air level shifts when the patient moves from the supine to the right lateral decubitus position. The edge of the liver is palpated 2 cm below the costal margin. His hemoglobin concentration is 10.3 g/dL, leukocyte count is 4,200/mm3, and platelet count is 124,000/mm3. Intravenous fluids and octreotide are started. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Intravenous ceftriaxone", "options": {"A": "Transfusion of packed red blood cells", "B": "Endoscopic band ligation", "C": "Intravenous ceftriaxone", "D": "Transjugular intrahepatic portal shunt", "E": "Balloon tamponade"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 33-year-old woman presents with lethargy and neck pain. She says that, for the past 6 months, she has been feeling tired all the time and has noticed a lot of muscle tension around the base of her neck. She also says she finds herself constantly worrying about everything, such as if her registered mail would reach family and friends in time for the holidays or if the children got their nightly bath while she was away or the weekend. She says that this worrying has prevented her from sleeping at night and has made her more irritable and edgy with her family and friends. Which of the following is the best course of treatment for this patient?", "answer": "Buspirone", "options": {"A": "Buspirone", "B": "Diazepam", "C": "Family therapy", "D": "Support groups", "E": "A vacation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman, gravida 2, para 1, at 26 weeks' gestation comes to the emergency department because of vaginal bleeding and epistaxis for the past 2 days. She missed her last prenatal visit 2 weeks ago. Physical examination shows blood in the posterior pharynx and a uterus consistent in size with 23 weeks' gestation. Her hemoglobin concentration is 7.2 g/dL. Ultrasonography shows an intrauterine pregnancy with a small retroplacental hematoma and absent fetal cardiac activity. Further evaluation is most likely to show which of the following findings?", "answer": "Decreased fibrinogen concentration", "options": {"A": "Increased platelet count", "B": "Increased antithrombin concentration", "C": "Decreased prothrombin time", "D": "Increased factor V concentration", "E": "Decreased fibrinogen concentration"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old woman presents to her primary care physician because of fever, fatigue, and shortness of breath. She has noticed that she has a number of bruises, but she attributes this to a hike she went on 1 week ago. She has diabetes and hypertension well controlled on medication and previously had an abdominal surgery but doesn’t remember why. On physical exam, she has some lumps in her neck and a palpable liver edge. Peripheral blood smear shows white blood cells with peroxidase positive eosinophilic cytoplasmic inclusions. The abnormal protein most likely seen in this disease normally has which of the following functions?", "answer": "Recruiting histone acetylase proteins", "options": {"A": "Binding as cofactor to kinases", "B": "Binding to anti-apoptotic factors", "C": "Inhibiting pro-apoptotic factors", "D": "Interacting with IL-3 receptor", "E": "Recruiting histone acetylase proteins"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old girl is brought to the physician because of amenorrhea for 4 months. Menses previously occurred at regular 28-day intervals and last for 3 to 4 days. There is no family history of serious illness. She receives good grades in school and is on the high school track team. She is sexually active with one male partner and uses condoms consistently. She appears thin. Examination shows bilateral parotid gland enlargement. There is fine hair over the trunk. Serum studies show:\nThyroid-stimulating hormone 3.7 μU/mL\nProlactin 16 ng/mL\nEstradiol 23 pg/mL (N > 40)\nFollicle-stimulating hormone 1.6 mIU/mL\nLuteinizing hormone 2.8 mIU/mL\nA urine pregnancy test is negative. Which of the following is the most likely cause of these findings?\"", "answer": "Nutritional deficiency", "options": {"A": "Exogenous steroid use", "B": "Defective androgen receptors", "C": "Gonadal dysgenesis", "D": "Abnormal neuronal cell migration", "E": "Nutritional deficiency"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 52-year-old man with chronic alcoholism presents to an ambulatory medical clinic, where the hepatologist elects to perform comprehensive hepatitis B screening, in addition to several other screening and preventative measures. Given the following choices, which serologic marker, if positive, would indicate the patient has immunity to the hepatitis B virus?", "answer": "HBsAb", "options": {"A": "HBsAgrn", "B": "HBsAb", "C": "HBcAbrn", "D": "HBeAg", "E": "HBeAb"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old woman presents with memory problems for the past few weeks. Patient vividly describes how she forgot where she put her car keys this morning and did not remember to wish her grandson a happy birthday last week. Patient denies any cognitive problems, bowel/bladder incontinence, tremors, gait problems, or focal neurologic signs. Patient mentions she wants to take Ginkgo because her friend told her that it can help improve her brain function and prevent memory loss. Past medical history is significant for an acute cardiac event several years ago. Current medications are aspirin, carvedilol, and captopril. Patient denies any history of smoking, alcohol or recreational drug use. Patient is a widow, lives alone, and is able to perform all activities of daily living (ADLs) easily. No significant family history. Patient is afebrile and vital signs are within normal limits. Physical examination is unremarkable. Which of the following would be the most appropriate response to this patient’s request to take Ginkgo?", "answer": "\"No, taking ginkgo will increase your risk for bleeding.\"", "options": {"A": "\"Yes, ginkgo is widely used for improving brain function and memory.\"", "B": "\"No, taking ginkgo will increase your risk for bleeding.\"", "C": "\"Yes, gingko may not help with your memory, but there is no risk of adverse events so it is safe to take.\"", "D": "“No, herbal preparations are unsafe because they are not regulated by the FDA.”", "E": "“No, you have Alzheimer's disease and need to start donepezil.”"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old man comes to the physician because of excessive daytime sleepiness for 5 months. He wakes up frequently at night, and his wife says his snoring has become louder. He is 180 cm (5 ft 10 in) tall and weighs 104 kg (230 lb); his BMI is 33 kg/m2. His pulse is 80/min and his respiratory rate is 11/min. His jugular venous pressure is 7 cm H2O. He has 2+ pitting edema of the lower legs and ankles. Arterial blood gas analysis on room air shows a pH of 7.42 and a PCO2 of 41 mm Hg. An x-ray of the chest shows normal findings. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Intermittent collapse of the oropharynx", "options": {"A": "Increased medullary ventilatory responsiveness", "B": "Impaired myocardial relaxation", "C": "Decreased levels of hypocretin-1", "D": "Intermittent collapse of the oropharynx", "E": "Daytime alveolar hypoventilation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman with a history of a \"heart murmur since childhood\" presents following a series of syncopal episodes over the past several months. She also complains of worsening fatigue over this time period, and notes that her lips have begun to take on a bluish tinge, for which she has been using a brighter shade of lipstick. You do a careful examination, and detect a right ventricular heave, clubbing of the fingers, and 2+ pitting edema bilaterally to the shins. Despite your patient insisting that every doctor she has ever seen has commented on her murmur, you do not hear one. Transthoracic echocardiography would most likely detect which of the following?", "answer": "Positive bubble study", "options": {"A": "Aortic stenosis", "B": "Mitral insufficiency", "C": "Positive bubble study", "D": "Ventricular aneurysm", "E": "Dynamic left ventricular outflow tract obstruction"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old woman comes to the emergency department with gradually worsening pain in the abdomen and right flank. The abdominal pain started one week ago and is accompanied by foul-smelling, lightly-colored diarrhea. The flank pain started two days ago and is now an 8 out of 10 in intensity. It worsens on rapid movement. She has a history of intermittent knee arthralgias. She has refractory acid reflux and antral and duodenal peptic ulcers for which she currently takes omeprazole. She appears fatigued. Her pulse is 89/min and her blood pressure is 110/75 mmHg. Abdominal examination shows both epigastric and right costovertebral angle tenderness. Urine dipstick shows trace red blood cells (5–10/μL). Ultrasonography shows mobile hyperechogenic structures in the right ureteropelvic junction. Further evaluation is most likely going to show which of the following findings?", "answer": "Hypercalcemia", "options": {"A": "Hypertensive crisis", "B": "Cutaneous flushing", "C": "Hypercalcemia", "D": "Pulmonary stenosis", "E": "QT prolongation on ECG"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 53-year-old woman presents to a physician with a cough which she has had for the last 5 years. She mentions that her cough is worse in the morning and is associated with significant expectoration. There is no history of weight loss or constitutional symptoms like fever and malaise. Her past medical records show that she required hospitalization for breathing difficulty on 6 different occasions in the last 3 years. She also mentions that she was never completely free of her respiratory problems during the period between the exacerbations and that she has a cough with sputum most of the months for the last 3 years. She works in a cotton mill and is a non-smoker. Her mother and her maternal grandmother had asthma. Her temperature is 37.1°C (98.8°F), the pulse is 92/min, the blood pressure is 130/86 mm Hg, and her respiratory rate is 22/min. General examination shows obesity and mild cyanosis. Auscultation of her chest reveals bilateral coarse rhonchi. Her lung volumes on pulmonary function test are given below:\n  Pre-bronchodilator Post-bronchodilator\nFEV1 58% 63%\nFVC  90% 92%\nFEV1/FVC  0.62 0.63\nTLC 98% 98%\nThe results are valid and repeatable as per standard criteria. Which of the following is the most likely diagnosis?", "answer": "Chronic bronchitis", "options": {"A": "Asthma", "B": "Chronic bronchitis", "C": "Emphysema", "D": "Idiopathic pulmonary fibrosis", "E": "Extrinsic allergic alveolitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the physician because of increasing shortness of breath for 1 month. Initially, he was able to climb the 3 flights of stairs to his apartment, but he now needs several breaks to catch his breath. He has no chest pain. He has rheumatic heart disease and type 2 diabetes mellitus. He emigrated from India about 25 years ago. The patient's current medications include carvedilol, torsemide, and insulin. He appears uncomfortable. His temperature is 37.3°C (99.1°F), pulse is 72/min and regular, respirations are 18/min, and blood pressure is 130/80 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Examination shows bilateral crackles at the lung bases. There is an opening snap followed by a low-pitched diastolic murmur at the fifth left intercostal space at the mid-clavicular line. An x-ray of the chest shows left atrial enlargement, straightening of the left cardiac border and increased vascular markings. Which of the following is the preferred intervention to improve this patient's symptoms?", "answer": "Percutaneous mitral balloon commissurotomy", "options": {"A": "Tricuspid valve repair", "B": "Mitral valve replacement", "C": "Percutaneous mitral balloon commissurotomy", "D": "Transcatheter aortic valve replacement", "E": "Enalapril therapy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70-year-old male presents to his primary care physician for complaints of fatigue. The patient reports feeling tired during the day over the past 6 months. Past medical history is significant for moderately controlled type II diabetes. Family history is unremarkable. Thyroid stimulating hormone and testosterone levels are within normal limits. Complete blood cell count reveals the following: WBC 5.0, hemoglobin 9.0, hematocrit 27.0, and platelets 350. Mean corpuscular volume is 76. Iron studies demonstrate a ferritin of 15 ng/ml (nl 30-300). Of the following, which is the next best step?", "answer": "Colonoscopy", "options": {"A": "MRI abdomen", "B": "Blood transfusion", "C": "CT abdomen", "D": "Gel electrophoresis", "E": "Colonoscopy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old woman presents with involuntary passage of urine and occasional watery vaginal discharge. She associates the onset of these symptoms with her discharge from the hospital for an abdominal hysterectomy and bilateral salpingo-oophorectomy for endometrial carcinoma and a left ovary cyst 2 months ago. The incontinence occurs during both day and night and is not related to physical exertion. She denies urgency, incomplete voiding, painful urination, or any other genitourinary symptoms. She is currently on hormone replacement therapy. Her vital signs are as follows: blood pressure, 120/80 mm Hg; heart rate, 77/min; respiratory rate, 13/min; and temperature, 36.6℃ (97.9℉). On physical examination, there is no costovertebral or suprapubic tenderness. The surgical scar is normal in appearance. The gynecologic examination revealed a small opening in the upper portion of the anterior wall of the vagina. No discharge was noted. How would you confirm the diagnosis?", "answer": "Voiding cystourethrography", "options": {"A": "Transabdominal ultrasound", "B": "Cystometry", "C": "Voiding cystourethrography", "D": "Antegrade pyelography", "E": "Urine flow test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 73-year-old man noted a rapid onset of severe dizziness and difficulty swallowing while watching TV at home. His wife reports that he had difficulty forming sentences and his gait was unsteady at this time. Symptoms were severe within 1 minute and began to improve spontaneously after 10 minutes. He has had type 2 diabetes mellitus for 25 years and has a 50 pack-year smoking history. On arrival to the emergency department 35 minutes after the initial development of symptoms, his manifestations have largely resolved with the exception of a subtle nystagmus and ataxia. His blood pressure is 132/86 mm Hg, the heart rate is 84/min, and the respiratory rate is 15/min. After 45 minutes, his symptoms are completely resolved, and neurological examination is unremarkable. Which of the following is the most likely cause of this patient’s condition?", "answer": "Vertebral artery occlusion", "options": {"A": "Anterior cerebral artery occlusion", "B": "Vertebral artery occlusion", "C": "Middle cerebral artery occlusion", "D": "Posterior cerebral artery occlusion", "E": "Lenticulostriate artery occlusion"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man is brought to the emergency department with increasing fever and abdominal pain over the past week. The pain is constant and limited to the lower right part of his abdomen. He has nausea but no vomiting or diarrhea. His past medical history is unremarkable for any serious illnesses. He takes acetaminophen for knee arthritis. He is fully alert and oriented. His temperature is 39.5°C (103.1°F), pulse is 89/min, respirations are 15/min, and blood pressure is 135/70 mm Hg. Abdominal examination shows a tender mass in the right lower quadrant. CT shows obstruction of the appendiceal neck with a fecalith and the appendiceal tip leading to an irregular walled-off fluid collection. Stranding of the surrounding fat planes is also noted. Intravenous hydration is initiated. Which of the following is the most appropriate next step in management?", "answer": "Antibiotics + CT-guided drainage", "options": {"A": "Antibiotics + CT-guided drainage", "B": "Antibiotics + interval appendectomy", "C": "Appendectomy within 12 hours", "D": "Early surgical drainage + interval appendectomy", "E": "Emergency appendectomy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 40-day-old child presents to a physician for the first time for a well-child visit. The mother is a 22-year-old college student who opted for a home birth. Upon examination, the child weighs 4.0 kg (8.8 lbs) and has intact reflexes. The umbilical cord is still attached and looks erythematous and indurated. A complete blood cell count reveals leukocytosis. Immunoglobulin levels are normal. A flow cytometry analysis is performed. Which of the following markers will most likely be deficient in this child?", "answer": "CD18", "options": {"A": "CD21", "B": "CD1a", "C": "CD3", "D": "CD56", "E": "CD18"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old woman presents for her routine annual examination. She has no complaints. She has a 3-year-old child who was born via normal vaginal delivery with no complications. She had a Pap smear during her last pregnancy and the findings were normal. Her remaining past medical history is not significant, and her family history is also not significant. Recently, one of her close friends was diagnosed with breast cancer at the age of 36, and, after reading some online research, she wants to be checked for all types of cancer. Which of the following statements would be the best advice regarding the most appropriate screening tests for this patient?", "answer": "“We should do a Pap smear now. Blood tests are not recommended for screening purposes.”", "options": {"A": "“We should do a Pap smear now. Blood tests are not recommended for screening purposes.”", "B": "“You need HPV (human papillomavirus) co-testing only.”", "C": "“Yes, you are right to be concerned. Let us do a mammogram and a blood test for CA-125.”", "D": "“Your last Pap smear 3 years ago was normal. We can repeat it after 2 more years.”", "E": "“Remember that information on the internet is vague and unreliable. You don't need any screening tests at this time.”"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 59-year-old woman presents to the physician for a 3-month history of progressively worsening shortness of breath on exertion and swelling of her legs. She has a history of breast cancer that was treated with surgery, followed by doxorubicin and cyclophosphamide therapy 4 years ago. Cardiac examination shows an S3 gallop, but there are no murmurs or rubs. Examination of the lower extremities shows pitting edema below the knees. Echocardiography is most likely to show which of the following sets of changes in this patient?\n  Aorto-ventricular pressure gradient\nDiastolic function Ventricular cavity size Ventricular wall thickness\nA Normal ↓ Normal Normal\nB Normal Normal ↑ ↑\nC Normal ↓ ↑ ↑\nD ↑ ↓ ↑ ↑\nE Normal Normal ↑ ↓", "answer": "E", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 19-year-old girl with a history of immune thrombocytopenic purpura (ITP), managed with systemic corticosteroids, presents with bruising, acne, and weight gain. Patient says that 3 months ago she gradually began to notice significant weight gain and facial and truncal acne. She says these symptoms progressively worsened until she discontinued her corticosteroid therapy 4 weeks ago. This week, she began to notice multiple bruises all over her body. Past medical history is significant for ITP, diagnosed 11 years ago, managed until recently with systemic corticosteroid therapy. The patient is afebrile and vital signs are within normal limits. On physical examination, there are multiple petechiae and superficial bruises on her torso and extremities bilaterally. There is moderate truncal obesity and as well as a mild posterior cervical adipose deposition. Multiple deep comedones are present on the face and upper torso. Which of the following is the best course of treatment in this patient?", "answer": "Splenectomy", "options": {"A": "Transplantation of stem cells", "B": "Administration of intravenous immunoglobulin", "C": "Continuation of systemic corticosteroid therapy", "D": "Splenectomy", "E": "Transfusion of thrombocytes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old boxer seeks evaluation by his physician after he noticed swelling at the angle of his jaw a few days ago. He recalls a recent boxing match when he was punched in his face. He says that his jaw is very painful. On examination, a firm mass is palpated, measuring 4 x 4 cm. An ultrasound was performed, which shows a thin, encapsulated, well-circumscribed, predominantly solid mass with occasional cystic areas. The mass is surgically excised, after which he develops a hoarse voice for a few days, but recovers within 1 week. The histopathologic evaluation of the surgical specimen reports a pseudocapsule with a hypocellular stromal component consisting of a myxoid background and cartilage arranged in clusters and a hypercellular epithelial component with cells arranged in sheets and trabeculae. From which of the following structures did the mass most likely arise?", "answer": "Parotid gland", "options": {"A": "Minor salivary gland", "B": "Thyroid", "C": "Parotid gland", "D": "Salivary duct", "E": "Seventh cranial nerve"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old woman comes to the physician because of a 2-week history of involuntary loss of urine. She loses small amounts of urine in the absence of an urge to urinate and for no apparent reason. She also reports that she has an intermittent urinary stream. Two years ago, she was diagnosed with multiple sclerosis. Current medications include glatiramer acetate and a multivitamin. She works as a librarian. She has 2 children who attend middle school. Vital signs are within normal limits. The abdomen is soft and nontender. Pelvic examination shows no abnormalities. Neurologic examination shows a slight hypesthesia in the lower left arm and absent abdominal reflex, but otherwise no abnormalities. Her post-void residual urine volume is 131 mL. Bladder size is normal. Which of the following is the most likely cause of the patient's urinary incontinence?", "answer": "Detrusor sphincter dyssynergia", "options": {"A": "Cognitive impairment", "B": "Vesicovaginal fistula", "C": "Detrusor sphincter dyssynergia", "D": "Bladder outlet obstruction", "E": "Impaired detrusor contractility"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old female comes to see her doctor for a rapidly enlarging abdomen and swelling of both legs. She was hospitalized 2 weeks ago for an upper gastrointestinal bleeding episode. On that occasion, her esophagogastroduodenoscopy showed grade 1 esophageal varices and a 1 cm clean-based antral ulcer. The patient was discharged on omeprazole. Review of symptoms shows that the patient is forgetful, does not sleep well, and is drowsy and fatigued during the day which prevents her from working full-time. She denies abdominal pain. The patient has a 10-year history of type 2 diabetes mellitus, hypertension, and hypercholesterolemia but no history of angina or coronary heart disease. She drank alcohol moderately heavy in her twenties and currently drinks less than 3 drinks per week and does not smoke. Her family history is unremarkable. On physical examination, her blood pressure is 132/82 mm Hg, pulse is 88/min, and her temperature is 37.0°C (98.6°F). She weighs 106.6 kg (235 lb) and her BMI is 33. She is alert, oriented to person, place, year, and month but not to the day. Her sclerae are nonicteric. Her pulmonary and cardiovascular exam are normal but her abdomen is distended with a fluid wave and mild tenderness to palpation. There is no hepatosplenomegaly. There is a 2+ edema to mid-calf and pedal pulses are barely palpable. Her neurological exam is without motor or sensory deficits but she demonstrates flapping tremor of her hands while asked to hold them in front of her for a few seconds and her skin exam shows a few spider telangiectasias on her face and upper chest. After an initial evaluation, lab tests were obtained:\nSerum sodium 133 mEq/L\nSerum potassium 3.8 mEq/L\nBUN 8 mg/dL\nSerum creatinine 1.0 mg/dL\nSerum albumin 2.5 mg/dL\nAspartate aminotransferase 68 IU/ml\nAlanine aminotransferase  46 IU/ml\nAlkaline phosphatase  130 IU/ml\nTotal bilirubin  1.8 mg/dL\n WBC count 4,200/mm3\nPlatelets 94,000/mm3\nHematocrit 35.5%\nProthrombin time (INR) 1.5\nA liver biopsy is performed and the results are pending. The hepatocytes causing her acute issue are predominantly located in which area of the hepatic lobule?\n ", "answer": "The zone closest to the centrolobular vein", "options": {"A": "The zone where gluconeogenesis is predominant", "B": "The zone receiving the most oxygenated blood from the hepatic artery", "C": "The zone with little or no cytochrome P450 enzymes", "D": "The zone closest to the centrolobular vein", "E": "The zone involved in cholesterol synthesis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old woman comes to the physician because of a 6-week history of fever and productive cough with blood-tinged sputum. She has also had a 4-kg (8.8-lb) weight loss during the same time period. Examination shows enlarged cervical lymph nodes. An x-ray of the chest shows a 2.5-cm pulmonary nodule in the right upper lobe. A biopsy specimen of the lung nodule shows caseating granulomas with surrounding multinucleated giant cells. Which of the following is the most likely underlying cause of this patient's pulmonary nodule?", "answer": "Delayed T cell-mediated reaction", "options": {"A": "IgE-mediated mast cell activation", "B": "Delayed T cell-mediated reaction", "C": "Antibody-mediated cytotoxic reaction", "D": "Combined type III/IV hypersensitivity reaction", "E": "Immune complex deposition\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old man comes to the emergency department because of a 1-week history of fever, throat pain, and difficulty swallowing. Head and neck examination shows an erythematous pharynx with purulent exudates overlying the palatine tonsils. Microscopic examination of a throat culture shows pink, spherical bacteria arranged in chains. Treatment with amoxicillin is initiated. A day later, a physician colleague from another department approaches the physician in the lobby of the hospital and asks about this patient, saying, “Did you see him? What does he have? He’s someone I play football with and he hasn’t come to play for the past 5 days. I’m worried about him.” Which of the following is the most appropriate action by the physician?", "answer": "Inform the colleague that she cannot divulge any information about the patient", "options": {"A": "Inform the colleague that she cannot divulge any information about the patient", "B": "Inform the colleague that he should ask the patient's attending physician", "C": "Tell her colleague that she cannot tell him the diagnosis but that his friend was treated with antibiotics", "D": "Tell her colleague the patient's case file number so he can look it up himself", "E": "Ask the colleague to meet in her office so they can discuss the patient in private"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old African American woman comes to the physician because of fatigue and difficulty swallowing for 6 weeks. She also complains of painful discoloration in her fingers when exposed to cold weather. She has smoked one pack of cigarettes daily for 4 years. She appears younger than her stated age. Physical examination shows smooth, swollen fingers with small white calcifications on her fingertips bilaterally. This patient is at increased risk for which of the following complications?", "answer": "Pulmonary hypertension", "options": {"A": "Liver cirrhosis", "B": "Chronic obstructive pulmonary disease", "C": "Pulmonary hypertension", "D": "Aortic aneurysm", "E": "Chondrocalcinosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 61-year-old man presents to the emergency room with a painful, swollen left leg. He states that his symptoms began that morning after a long flight from Australia. He denies shortness of breath, chest pain, or cough. On review of systems, he notes that he has been constipated recently and had several episodes of bright red blood per rectum. He has not noticed any weight loss, fevers, or night sweats. He has a past medical history of a deep vein thrombosis 4 years ago during a hospitalization for community acquired pneumonia and was treated with warfarin for 3 months afterward. He also has chronic hepatitis C from previous intravenous drug use. The patient has a 30 pack-year smoking history and has never had a colonoscopy. His father is 84-years-old and has chronic kidney disease from diabetes, and his mother passed away from a massive pulmonary embolus when pregnant with his younger sister. In the emergency room, his temperature is 98.7°F (37.1°C), blood pressure is 142/85 mm/Hg, pulse is 79/min, and respirations are 14/min. On exam, he is in no acute distress. His left calf is larger in caliber than the right calf which is red and tender to palpation. Dorsiflexion of the foot worsens the pain. His abdomen is soft, nontender, and nondistended without hepatomegaly. The remainder of the physical exam is unremarkable. Labs are shown below:\n\nHemoglobin: 13.0 g/dL\nLeukocyte count: 6,000/mm^3\nPlatelets: 160,000/mm^3\n\nAspartate aminotransferase: 15 U/L\nAlanine aminotransferase: 19 U/L\nAlkaline phosphatase: 81 IU/L\nHepatitis C antibody: reactive\nHepatitis C titer: 0 copies/mL\n\nWhich of the following is the most likely cause of this patient’s condition?", "answer": "Resistance of factor V to inactivation by protein C", "options": {"A": "Protein C deficiency", "B": "Increased estrogen levels", "C": "Loss of antithrombin III in urine", "D": "Resistance of factor V to inactivation by protein C", "E": "Malignancy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old woman with breast cancer presents to her primary care physician for referral to a medical oncologist. She denies any personal history of blood clots in her past. Her past medical history is significant for preeclampsia, hypertension, polycystic ovarian syndrome, and hypercholesterolemia. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and she currently denies any illicit drug use, despite a history of cocaine use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 111/min and irregular, and respiratory rate 17/min. On physical examination, she has a grade 2/6 holosystolic murmur heard best at the left upper sternal border, bilateral bibasilar crackles on the lungs, and a normal abdominal examination. At her follow-up with the oncologist, they subsequently plan to start the patient on a highly emetic chemotherapeutic regimen. Which of the following regimens for the treatment of chemotherapy-induced emesis is most appropriate for patients on the same day of treatment?", "answer": "Aprepitant + dexamethasone + 5-HT3 receptor antagonist", "options": {"A": "Dronabinol + dexamethasone", "B": "Aprepitant + dexamethasone + 5-HT3 receptor antagonist", "C": "Dexamethasone + 5-HT3 receptor antagonist", "D": "Prochlorperazine + dexamethasone + dronabinol", "E": "Aprepitant + dronabinol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A parent presents to her pediatrician requesting information about immunizations for her newborn. The pediatrician explains about basic principles of immunization, types of vaccines, possible adverse effects, and the immunization schedule. Regarding how immunizations work, the pediatrician explains that there are mainly 2 types of vaccines. The first type of vaccine provides stronger and more lasting immunity as it induces both cellular and humoral immune responses. The second type of vaccine produces mainly a humoral response only, and its overall efficacy is less as compared to the first type. Which of the following vaccines belongs to the first type of vaccine that the pediatrician is talking about?", "answer": "Yellow fever vaccine", "options": {"A": "Yellow fever vaccine", "B": "Rabies vaccine", "C": "Hepatitis A vaccine", "D": "Polio vaccine (Salk)", "E": "Hepatitis B vaccine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 22-year-old man, accompanied by his brother, presents to the emergency department with palpitations for the past 30 minutes and nausea for the past hour. When the patient meets the physician, he says, “Doctor, I am the happiest person in the world because I have the best brain possible. It’s just that my heart is saying something, so I came to check with you to see what it is”. The brother says the patient was diagnosed with attention-deficit/hyperactivity disorder (ADHD) 5 years ago. When the doctor asks the patient about his ADHD treatment, he replies, “Doctor, the medicine is wonderful, and I love it very much. I often take one or two tablets extra!” He has no history of a known cardiovascular disorder, alcohol abuse, or smoking. The patient’s temperature is 99.2ºF (37.3ºC), heart rate is 116/minute, respiratory rate is 18/minute, and blood pressure is 138/94 mm Hg. Generalized perspiration is present. Which of the following signs is most likely to be present on ocular examination?", "answer": "Dilated pupils", "options": {"A": "Dilated pupils", "B": "Rotatory nystagmus", "C": "Conjunctival injection", "D": "Bilateral foveal yellow spots", "E": "Bilateral optic disc edema"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 68-year-old man comes to the emergency department because of a 1-week history of worsening bouts of shortness of breath at night. He has had a cough for 1 month. Occasionally, he has coughed up frothy sputum during this time. He has type 2 diabetes mellitus and long-standing hypertension. Two years ago, he was diagnosed with Paget disease of bone during a routine health maintenance examination. He has smoked a pack of cigarettes daily for 20 years. His temperature is 37°C (98.6°F), pulse is 110/min, respirations are 25/min, and blood pressure is 145/88 mm Hg. Current medications include metformin, alendronate, hydrochlorothiazide, and enalapril. Examination shows bibasilar crackles. Cardiac examination shows a dull, low-pitched sound during late diastole that is best heard at the apex. There is no jugular venous distention or peripheral edema. Arterial blood gas analysis on room air shows:\npH 7.46\nPCO2 29 mm Hg\nPO2 83 mm Hg\nHCO3- 18 mEq/L\nEchocardiography shows a left ventricular ejection fraction of 55%. Which of the following is the most likely underlying cause of this patient’s current condition?\"", "answer": "Impaired myocardial relaxation", "options": {"A": "Destruction of alveolar walls", "B": "Decreased myocardial contractility", "C": "Diuretic overdose", "D": "Systemic arteriovenous fistulas", "E": "Impaired myocardial relaxation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old man comes to the physician for hematemesis and progressive heartburn over the past 5 days. Ten days ago, he was started on a medication to treat a condition that causes hearing difficulties and pain of the lower legs. He has no other history of serious illness. He has smoked 1 pack of cigarettes daily for the past 20 years. Physical examination shows bowing of the tibias. Upper endoscopy shows inflammation of the mucosa and a 1-cm punched-out ulcer in the distal esophagus. Which of the following drugs is the most likely cause of the patient's current condition?", "answer": "Risedronate", "options": {"A": "Calcium citrate", "B": "Denosumab", "C": "Risedronate", "D": "Prednisolone", "E": "Acetaminophen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old male died in a motor vehicle accident. Autopsy reveals extensive atherosclerosis of his left anterior descending artery marked by intimal smooth muscle and collagen proliferation. Which of the following is implicated in recruiting smooth muscle cells from the media to intima in atherosclerotic lesions?", "answer": "Platelet-derived growth factor", "options": {"A": "IgE", "B": "Prostacyclin", "C": "Vascular endothelial growth factor", "D": "Factor V Leiden", "E": "Platelet-derived growth factor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old man presents to the emergency room with severe abdominal pain. He states that for the entire day, he has had pain in his lower right abdomen in addition to a loss of appetite accompanied by nausea and vomiting. His temperature is 101.3°F (38.5°C), blood pressure is 125/98 mmHg, pulse is 78/min, and respirations are 15/min. On physical examination, he exhibits increased abdominal pain in his right lower quadrant upon deep palpation of the left lower quadrant. What is the next step in the management of this patient?", "answer": "Laparoscopic surgery", "options": {"A": "Abdominal radiograph", "B": "Abdominal ultrasound", "C": "Colonoscopy", "D": "Laparoscopic surgery", "E": "Stool ova and parasite examination"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2400-g (5.29-lb) male newborn is delivered at term to a 26-year-old woman. Physical examination shows a sloping forehead, a flat nasal bridge, increased interocular distance, low-set ears, and a protruding tongue. There is a single palmar crease and an increased gap between the first and second toe. The abdomen is distended. An x-ray of the abdomen shows two large air-filled spaces in the upper quadrant. Karyotype analysis shows 46 chromosomes in all tested cells. Which of the following is the most likely underlying cause of this patient's findings?", "answer": "Unbalanced translocation", "options": {"A": "Balanced translocation", "B": "Meiotic nondisjunction", "C": "Mitotic nondisjunction", "D": "Unbalanced translocation", "E": "Uniparental disomy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old boy is brought to his pediatrician for a regular checkup by his mother. The patient’s mother is concerned about a slight deviation of his left eye and she also notes that her child’s left eye looks strange on the photos, especially if there is a flash. The patient is the first child in the family born to a 31-year-old woman. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Family history is unremarkable. The eye examination shows left eye converging strabismus. The pupillary reflex cannot be elicited from an illumination of the left eye. Fundal examination reveals are shown in the picture. On testing, visual evoked potential cannot be elicited from the left retina but is normal from the right retina. MRI of the orbits shows a retina-derived tumor in the left eye with an initial spread along the intrabulbar part of the optic nerve and vitreous seeding. The other eye is completely intact. Which of the following methods of treatment is indicated for this patient?", "answer": "Eye enucleation", "options": {"A": "Brachytherapy", "B": "Chemotherapy", "C": "Eye enucleation", "D": "Cryotherapy", "E": "Laser coagulation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 21-year-old man comes to the physician because of a 3-day history of yellowing of his eyes. He has also noticed a decrease in his exercise capacity and gets quickly exhausted after minor physical activity. Examination shows scleral icterus and pale mucous membranes. He has splenomegaly. His hemoglobin concentration is 7.9 mg/dL, leukocyte is count 8500/mm3, and platelet count is 187,000/mm3. Direct antiglobulin and heterophile antibody tests are positive. Which of the following additional laboratory findings are most likely present in this patient?", "answer": "Decreased haptoglobin levels", "options": {"A": "Decreased reticulocyte count", "B": "Decreased haptoglobin levels", "C": "Decreased mean corpuscular volume", "D": "Increased direct to total bilirubin ratio", "E": "Increased bleeding time"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 24-year-old woman comes to the physician because of a 1-day history of painful rash after spending several hours in the sun. Skin examination shows well-demarcated areas of erythema with some scaling on the face, chest, upper back, and arms. The affected areas are hot and sensitive to touch. The oral mucosa appears normal. Which of the following is the most likely underlying mechanism of this patient's skin findings?", "answer": "Apoptosis of keratinocytes in the epidermis", "options": {"A": "Vascular endothelial cell injury in the superficial dermis", "B": "Immune complex deposits at the dermoepidermal junction", "C": "Mast cell activation in the superficial dermis", "D": "Apoptosis of keratinocytes in the epidermis", "E": "T-cell-mediated inflammatory reaction in the dermis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Sixteen hours after delivery, a newborn develops respiratory distress. She was born at 38 weeks' gestation with a birth weight of 3200 g (7 lb 1 oz). Pregnancy was complicated by polyhydramnios. Physical examination shows tachypnea and bluish discoloration of the extremities. Auscultation of the chest shows diffuse crackles in the lung fields and a harsh holosystolic murmur at the left lower sternal border. Abdominal x-ray shows absence of bowel gas. Which of the following best explains the pathogenesis of this newborn's condition?", "answer": "Defect in mesodermal differentiation", "options": {"A": "Defect in the pleuroperitoneal membrane", "B": "Deletion in the long arm of chromosome 7", "C": "Defect in mesodermal differentiation", "D": "Absence of dynein", "E": "Deletion in the long arm of chromosome 22"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 46-year-old male presents to his dermatologist for routine follow-up of his psoriasis. He was last seen in the office six months prior, at which time he started undergoing ultraviolet light therapy. He reports that he initially noticed an improvement in his symptoms but the effects were transient. He has also started noticing pain and stiffness in his fingers. His past medical history is notable for obesity and diabetes mellitus. He takes metformin. His temperature is 99°F (37.2°C), blood pressure is 130/80 mmHg, pulse is 80/min, and respirations are 16/min. Multiple plaques with scaling are noted on the extensor surfaces of the upper and lower extremities. The patient’s physician suggests stopping the ultraviolet light therapy and starting an injectable medication that acts as a decoy receptor for a pro-inflammatory cytokine. Which of the following is an adverse effect associated with the use of this medication?", "answer": "Reactivation of latent tuberculosis", "options": {"A": "Reactivation of latent tuberculosis", "B": "Nephrotoxicity", "C": "Myelosuppression", "D": "Cushing’s syndrome", "E": "Retinopathy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man comes to the physician because of a lesion on his eyelid for 6 months. The lesion is not painful or pruritic. He initially dismissed it as a 'skin tag' but the lesion has increased in size over the past 3 months. He has type 2 diabetes mellitus, coronary artery disease, and left hemiplegia from a stroke 3 years ago. Current medications include sitagliptin, metformin, aspirin, and simvastatin. He used to work as a construction contractor and retired 3 years ago. Examination shows a 1-cm (0.4-in) flesh-colored, nodular, nontender lesion with rolled borders. There is no lymphadenopathy. Cardiopulmonary examination shows no abnormalities. Muscle strength is reduced in the left upper and lower extremities. Visual acuity is 20/20. The pupils are equal and reactive to light. A shave biopsy confirms the diagnosis. Which of the following is the most appropriate next step in management?", "answer": "Mohs micrographic surgery", "options": {"A": "Wide local excision", "B": "Cryotherapy", "C": "Topical chemotherapy", "D": "Mohs micrographic surgery", "E": "Laser ablation\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old man comes to the physician because of a 2-week history of dizziness, fatigue, and shortness of breath. He has noticed increased straining with bowel movements and decreased caliber of his stools over the past 3 months. He has no history of medical illness and takes no medications. He appears pale. Physical examination shows mild tachycardia and conjunctival pallor. Test of the stool for occult blood is positive. His hemoglobin concentration is 6.4 g/dL, and mean corpuscular volume is 74 μm3. A double-contrast barium enema study in this patient is most likely to show which of the following?", "answer": "Filling defect of the rectosigmoid colon", "options": {"A": "Thumbprint sign of the transverse colon", "B": "Lead pipe sign of the descending colon", "C": "Diverticula in the sigmoid colon", "D": "Filling defect of the rectosigmoid colon", "E": "String sign in the terminal ileum"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man is brought to the emergency department 30 minutes after the sudden onset of severe, migrating anterior chest pain, shortness of breath, and sweating at rest. He has hypertension, hypercholesterolemia, and type 2 diabetes mellitus. Medications include atorvastatin, hydrochlorothiazide, lisinopril, and metformin. He has smoked one pack of cigarettes daily for 25 years. He is in severe distress. His pulse is 110/min, respirations are 20/min, and blood pressure is 150/85 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Cardiac examination shows a grade 3/6, high-pitched, blowing, diastolic murmur heard best over the right sternal border. The lungs are clear to auscultation. Femoral pulses are decreased bilaterally. An ECG shows sinus tachycardia and left ventricular hypertrophy. Which of the following is the most likely diagnosis?", "answer": "Aortic dissection", "options": {"A": "Pulmonary embolism", "B": "Esophageal rupture", "C": "Aortic dissection", "D": "Spontaneous pneumothorax", "E": "Papillary muscle rupture"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 19-year-old woman undergoes an laparoscopic appendectomy for acute appendicitis. During the procedure, a black, discolored liver is noted. Other than the recent appendicitis, the patient has no history of serious illness and takes no medications. She has no medication allergies. She does not drink alcohol or use illicit drugs. She has an uncomplicated postoperative course. At her follow-up visit 3 weeks later, her vital signs are within normal limits. Examination shows scleral icterus, which the patient states has been present for many years. Abdominal examination shows healing scars without drainage or erythema. Serum studies show:\nAspartate aminotransferase 30 IU/L\nAlanine aminotransferase 35 IU/L\nAlkaline phosphatase 47 mg/dL\nTotal bilirubin 5.2 mg/dL\nDirect bilirubin 4.0 mg/dL\nWhich of the following is the most likely diagnosis?\"", "answer": "Dubin-Johnson syndrome", "options": {"A": "Type II Crigler-Najjar syndrome", "B": "Dubin-Johnson syndrome", "C": "Gilbert syndrome", "D": "Rotor syndrome", "E": "Wilson disease"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man with atrial fibrillation is brought to the emergency department by his wife 6 hours after the acute onset of right arm weakness and slurred speech. An MRI of the brain shows a thrombus in the left middle cerebral artery. Twelve hours later, the patient develops ventricular tachycardia. Despite appropriate care, he dies. Which of the following histopathologic changes are most likely to be seen on a biopsy specimen from the affected brain tissue?", "answer": "Eosinophilic neuronal cytoplasm with pyknotic nuclei", "options": {"A": "Neutrophilic infiltration with central necrosis", "B": "Reactive gliosis with vascular proliferation", "C": "Glial scarring with fibrous tissue hypertrophy", "D": "Eosinophilic neuronal cytoplasm with pyknotic nuclei", "E": "Normal brain parenchyma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 54-year-old woman is diagnosed with locally-advanced invasive ductal adenocarcinoma of the breast. She undergoes surgical resection, radiation therapy, and is now being started on adjunctive chemotherapy with cyclophosphamide and doxorubicin. The patient is scheduled for follow up by her primary care provider. Which of the following tests should be performed regularly to monitor her current treatment regimen?", "answer": "Echocardiography", "options": {"A": "Cardiac MRI", "B": "Chest radiograph", "C": "ECG", "D": "Echocardiography", "E": "No regular monitoring indicated"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man presents to his primary care physician for a new patient appointment. The patient states that he feels well and has no concerns at this time. The patient has a past medical history of hypertension, an elevated fasting blood glucose, and is not currently taking any medications. His blood pressure is 177/118 mmHg, pulse is 90/min, respirations are 16/min, and oxygen saturation is 97% on room air. Physical exam is notable for an obese man with atrophy of his limbs and striae on his abdomen. Laboratory values are notable for a blood glucose of 175 mg/dL. Which of the following is the best initial step in management?", "answer": "Dexamethasone suppression test", "options": {"A": "Dexamethasone suppression test", "B": "Hydrochlorothiazide", "C": "Metformin", "D": "MRI of the head", "E": "Weight loss"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old man presents with abdominal pain and bloody diarrhea. His symptoms have been recurrent for the past few months, and, currently, he says he is having on average four bowel movements daily, often bloody. He describes the pain as cramping and localized to the left side of his abdomen. He also says that he has lost around 4.5 kg (10 lb) over the past 3 months. There is no other significant past medical history and the patient is not on current medications. His temperature is 37.7° C (100.0° F), pulse rate is 100/min, respiratory rate is 18/min, and blood pressure is 123/85 mm Hg. On physical examination, there is mild tenderness to palpation in the lower left quadrant of the abdomen with no rebound or guarding. Laboratory studies show anemia and thrombocytosis. Colonoscopy is performed, which confirms the diagnosis of ulcerative colitis (UC). What is the mechanism of action of the recommended first-line medication for the treatment of this patient’s condition?", "answer": "Inhibition of leukotriene synthesis and lipoxygenase", "options": {"A": "Inhibition of leukotriene synthesis and lipoxygenase", "B": "TNF-⍺ antagonism", "C": "Suppression of cellular and humoral immunity", "D": "Inhibition of enzyme phospholipase A2", "E": "Cross-linking of DNA of the bacteria causing UC"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-year-old boy is brought to the emergency department by his mother because of a 2-hour history of word-finding difficulty, speech slurring, and weakness and sensory loss of his right arm and leg. He has not had fever, nausea, headache, or diarrhea. His mother reports an episode of severe pain and soft tissue swelling of the dorsum of his hands and feet when he was 12 months old, which self-resolved after 2 weeks. His temperature is 37.7°C (99.8°F), pulse is 90/min, and blood pressure is 110/80 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 91%. He follows commands but has nonfluent aphasia. Examination shows marked weakness and decreased sensation of the right upper and lower extremities. Deep tendon reflexes are 2+ bilaterally. Babinski sign is present on the right. An MRI scan of the brain shows signs of an evolving cerebral infarction on the patient's left side. Which of the following is the most appropriate initial step in management?", "answer": "Exchange transfusion therapy", "options": {"A": "Exchange transfusion therapy", "B": "Intravenous tissue plasminogen activator therapy", "C": "Hydroxyurea therapy", "D": "Heparin therapy", "E": "Aspirin therapy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 9-year-old girl presents with dyspnea, palpitations, joint pain, and fever for the past week. She says that her symptoms started 2 weeks ago with bilateral knee pain which has shifted to both ankles over the past week. She says she noticed bilateral leg swelling since yesterday. Past medical history is significant for a severe sore throat, fever, chills, and myalgia 1 month ago which resolved after a week. Her vital signs include: respiratory rate 22/min, temperature 37.7°C (100.0°F), blood pressure 90/60 mm Hg, pulse 90/min, and SpO2 88% on room air. On physical examination, the patient is ill-appearing with pallor and bilateral pitting edema of legs. The apex beat is prominently located in the 5th intercostal space in the mid-axillary line. Crepitus is noted over both lung bases bilaterally. A loud 3/6 pansystolic murmur is heard at the apex radiating towards the axilla. S3 and S4 sounds are noted at the left sternal border and cardiac apex. Which of the following is the most likely diagnosis in this patient?", "answer": "Acute rheumatic fever", "options": {"A": "Acute rheumatic fever", "B": "Mitral stenosis", "C": "Aortic regurgitation", "D": "Tricuspid regurgitation", "E": "Aortic stenosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 62-year-old woman with type 2 diabetes mellitus comes to the physician because of a 3-month history of fatigue and weakness. Her hemoglobin A1c concentration was 13.5% 12 weeks ago. Her blood pressure is 152/92 mm Hg. Examination shows lower extremity edema. Serum studies show:\nK+ 5.1 mEq/L\nPhosphorus 5.0 mg/dL\nCa2+ 7.8 mg/dL\nUrea nitrogen 60 mg/dL\nCreatinine 2.2 mg/dL\nWhich of the following is the best parameter for early detection of this patient’s renal condition?\"", "answer": "Urinary albumin", "options": {"A": "Urinary red blood cell casts", "B": "Serum total protein", "C": "Urinary albumin", "D": "Serum urea nitrogen", "E": "Serum creatinine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-year-old boy is brought to the pediatrician by his father because of recent changes in his behavior. His father states that he has noticed that the boy has begun to appear less coordinated than normal and has had frequent falls. On exam, the pediatrician observes pes cavus and hammer toes. The pediatrician makes a presumptive diagnosis based on these findings and recommends a formal echocardiogram. The pediatrician is most likely concerned about which of the following cardiovascular defects?", "answer": "Hypertrophic cardiomyopathy", "options": {"A": "Tetrology of fallot", "B": "Coarctation of the aorta", "C": "Endocardial cushion defect", "D": "Hypertrophic cardiomyopathy", "E": "Aortic cystic medial necrosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old girl presents to the emergency department with skin desquamation over her hips and buttocks and right arm; she also has conjunctivitis and fever. The patient was previously seen by her pediatrician for symptoms of impetigo around the nasal folds, and she was treated with topical fusidic acid. She was born at 39 weeks’ gestation via spontaneous vaginal delivery, is up to date on all vaccines, and is meeting all developmental milestones. Medical history and family history are unremarkable. She is admitted to the hospital and started on IV antibiotics. Today, her blood pressure is 100/60 mm Hg, heart rate is 100 beats per minute, respiratory rate is 22 breaths per minute, and temperature is 39.4°C (102.9°F). The total area of desquamation exceeds 20%, sparing the mucous membranes. She is transferred to the pediatric intensive care unit. What is the most likely cause of the disease?", "answer": "Staphylococcus aureus infection", "options": {"A": "Herpes simplex virus infection", "B": "Stevens-Johnson syndrome", "C": "Staphylococcus aureus infection", "D": "Bullous pemphigoid", "E": "Psoriasis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 22-year-old woman comes to the emergency department because of chest and epigastric pain that started just after vomiting 30 minutes ago. She does not take any medications and does not drink alcohol or smoke cigarettes. While in the emergency department, the patient experiences two episodes of forceful, bloody emesis. Her temperature is 99.1°F (37.3°C), pulse is 110/minute, and blood pressure is 105/60 mm Hg. Physical examination shows dental enamel erosion and calluses on the dorsal aspect of her right hand. There is tenderness to palpation in the epigastrium. An x-ray of the chest is normal. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Mucosal lacerations at the gastroesophageal junction", "options": {"A": "Dilated veins in the esophageal submucosa", "B": "Rupture of the distal esophagus", "C": "Clean-based gastric ulcer", "D": "Mucosal lacerations at the gastroesophageal junction", "E": "Friable mass in the distal esophagus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 86-year-old man is admitted to the hospital for management of pneumonia. His hospital course has been relatively uneventful, and he is progressing well. On morning rounds nearing the end of the patient's hospital stay, the patient's cousin finally arrives to the hospital for the first time after not being present for most of the patient's hospitalization. He asks about the patient's prognosis and potential future discharge date as he is the primary caretaker of the patient and needs to plan for his arrival home. The patient is doing well and can likely be discharged in the next few days. Which of the following is the most appropriate course of action?", "answer": "Explain that you cannot discuss the patient's care at this time", "options": {"A": "Bring the cousin to the room and ask the patient if it is acceptable to disclose his course", "B": "Bring the cousin to the room and explain the plan to both the patient and cousin", "C": "Explain that you cannot discuss the patient's care at this time", "D": "Explain the plan to discharge the patient in the next few days", "E": "Tell the cousin that you do not know the patient's course well"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old man presents with an occasional tremor in his left hand. While the tremor disappears when he moves his hand, he finds it increasingly difficult to type and feels his handwriting has gotten much smaller. He finds the tremor is more pronounced when he is stressed out at work. He also complains of a decrease in his sense of smell, mild constipation, difficulty sleeping, and increased urinary frequency – all of which he feels is him ‘just getting older’. No significant past medical history and no current medications. Vital signs are a pulse of 74/min, a respiratory rate of 14/min, a blood pressure of 130/70 mm Hg, and a temperature of 36.7°C (98.0°F). On physical examination, a resting tremor in the left hand is noted with mild rigidity in the upper limbs and mask-like faces. While performing finger-to-nose and rapid alternating movements, he has some difficulty. All his movements are slow. The sensation is intact. Gait is normal except for a decreased arm swing. Which of the following drugs acts directly on the receptors responsible for this patient’s condition?", "answer": "Bromocriptine", "options": {"A": "Selegiline", "B": "Bromocriptine", "C": "Carbidopa", "D": "Benztropine", "E": "Entacapone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 10-year-old boy is brought to the physician by his father, who is concerned because his son has been less interested in playing soccer with him recently. They used to play every weekend, but his son has started to tire easily and has complained of pain in his lower legs while running around on the soccer field. The boy has no personal or family history of serious illness. Cardiac examination shows a systolic ejection murmur best heard over the left sternal border that radiates to the left paravertebral region. An x-ray of the chest shows erosions of the posterior aspects of the 6th to 8th ribs. If left untreated, this patient is at greatest risk for which of the following?", "answer": "Intracranial hemorrhage", "options": {"A": "Intracranial hemorrhage", "B": "Central cyanosis", "C": "Paradoxical embolism", "D": "Abdominal aortic aneurysm", "E": "Right heart failure"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the physician because of progressive difficulty swallowing solids and liquids over the past 4 months. She has lost 4 kg (9 lb) during this period. There is no history of serious illness. She emigrated to the US from Panama 7 years ago. She does not smoke cigarettes or drink alcohol. Cardiopulmonary examination shows a systolic murmur and an S3 gallop. A barium radiograph of the chest is shown. Endoscopic biopsy of the distal esophagus is most likely to show which of the following?", "answer": "Absence of myenteric plexus neurons", "options": {"A": "Atrophy of esophageal smooth muscle cells", "B": "Presence of intranuclear basophilic inclusions", "C": "Infiltration of eosinophils in the epithelium", "D": "Absence of myenteric plexus neurons", "E": "Presence of metaplastic columnar epithelium"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old man is admitted to the hospital because of a 2-day history of fever, nausea, and abdominal pain. His temperature is 39.4°C (102.9°F) and pulse is 106/min. Physical examination shows tenderness in the right upper quadrant. Blood cultures grow nonhemolytic, gram-positive cocci that grow in hypertonic saline. Antibiotic sensitivity testing of the isolated organism shows that gentamicin has a minimum inhibitory concentration (MIC) of 16 μg/mL. The addition of ampicillin, which has an MIC of 2 μg/mL alone, decreases the MIC of gentamicin to 0.85 μg/mL. The decrease in the MIC of gentamicin with the addition of ampicillin is most likely due to which of the following mechanisms?", "answer": "Increase in the intracellular uptake of gentamicin", "options": {"A": "Additive bacteriostatic effect of ampicillin", "B": "Increase in the intracellular uptake of gentamicin", "C": "Stabilization of gentamicin binding at the target site", "D": "Inhibition of the acetylation of gentamicin", "E": "Sequential block of essential micronutrient synthesis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old boy is brought to the physician because of a painful, burning rash on his left arm for 3 days. Three years ago, he was diagnosed with heart failure due to congenital heart disease and received an allogeneic heart transplantation. He takes cyclosporine to prevent chronic transplant rejection. He has not received any routine childhood vaccinations. A photograph of the rash is shown. Microscopic examination of a skin biopsy specimen is most likely to show which of the following findings?", "answer": "Multinucleated epidermal giant cells and intranuclear inclusions", "options": {"A": "Eosinophilic spongiosis and subepidermal blister formation", "B": "Multinucleated epidermal giant cells and intranuclear inclusions", "C": "Papillary microabscesses and granular deposits of IgA", "D": "Fungal hyphae and hyperkeratosis", "E": "Gram-positive cocci and spongiotic dermatitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old woman with refractory gastrointestinal complaints undergoes a bowel biopsy. On histology, the pathologist observes that submucosal glands of Brunner are present in the specimen. Which portion of the bowel was most likely biopsied?", "answer": "Duodenum", "options": {"A": "Duodenum", "B": "Jejunum", "C": "Ileum", "D": "Cecum", "E": "Descending colon"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man is brought to the emergency department because of a 3-day history of increasing shortness of breath and chest pain. He has had a productive cough with foul-smelling sputum for 1 week. He has gastritis as well as advanced Parkinson disease and currently lives in an assisted-living community. He smoked one pack of cigarettes daily for 40 years but quit 5 years ago. He has a 30-year history of alcohol abuse but has not consumed any alcohol in the past 5 years. His temperature is 39.3°C (102.7°F), he is tachycardic and tachypneic and his oxygen saturation is 77% on room air. Auscultation of the lung shows rales and decreased breath sounds over the right upper lung field. Examination shows a resting tremor. Laboratory studies show:\nHematocrit 38%\nLeukocyte count 17,000/mm3\nPlatelet count 210,000/mm3\nLactic acid 4.1 mmol/L (N=0.5–1.5)\nA x-ray of the chest shows infiltrates in the right upper lobe. Which of the following is the most significant predisposing factor for this patient's respiratory symptoms?\"", "answer": "Parkinson disease\n\"", "options": {"A": "Living in an assisted-living community", "B": "Tobacco use history", "C": "Past history of alcohol abuse", "D": "Gastritis", "E": "Parkinson disease\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old man comes to the physician because of palpitations, shortness of breath, diarrhea, and abdominal cramps for 2 months. Physical examination shows cutaneous flushing of the face. Auscultation of the chest shows bilateral wheezing. A 24-hour urine collection shows increased 5-hydroxyindoleacetic acid (5-HIAA) concentration. A contrast-enhanced CT scan of the abdomen shows an intestinal tumor with extensive metastasis to the liver. A diagnosis of an inoperable disease is made and the patient is started on treatment with octreotide. Six weeks later, the patient's symptoms have improved except for his abdominal pain and frequent loose stools. The physician suggests enrolling the patient in a trial to test additional treatment with a new drug that has been shown to improve symptoms in other patients with the same condition. The expected beneficial effect of this new drug is most likely caused by inhibition of which of the following?", "answer": "Tryptophan hydroxylase", "options": {"A": "Dopamine β-hydroxylase", "B": "Vasoactive intestinal peptide", "C": "Plasma kallikrein", "D": "Histidine decarboxylase", "E": "Tryptophan hydroxylase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old girl is brought to the physician because she has not attained menarche. There is no personal or family history of serious illness. She is 165 cm (5 ft 5 in) tall and weighs 60 kg (132 lb); BMI is 22 kg/m2. Breast development is Tanner stage 4, and pubic hair development is Tanner stage 1. Pelvic examination shows a blind vaginal pouch. This patient is most likely to have which of the following karyotypes?", "answer": "46,XY", "options": {"A": "45,XO", "B": "47,XYY", "C": "46,XX", "D": "46,XY", "E": "47,XXY"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old woman is brought to the emergency department after being struck by a car while crossing the street. She has major depressive disorder with psychosis. Current medications include sertraline and haloperidol. Vital signs are within normal limits. X-ray of the lower extremity shows a mid-shaft femur fracture. The patient is taken to the operating room for surgical repair of the fracture. As the surgeon begins the internal fixation, the patient shows muscle rigidity and profuse diaphoresis. Her temperature is 39°C (102.2°F), pulse is 130/min, respirations are 24/min, and blood pressure is 146/70 mm Hg. The pupils are equal and reactive to light. The end tidal CO2 is 85 mm Hg. Which of the following is the most appropriate treatment for this patient's condition?", "answer": "Dantrolene therapy", "options": {"A": "Dantrolene therapy", "B": "Fat embolectomy", "C": "Cyproheptadine therapy", "D": "Bromocriptine therapy", "E": "Propranolol therapy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 10-year-old girl is brought to the physician because of severe malaise, pink eyes, cough, and a runny nose for 3 days. She recently immigrated from Sudan and immunization records are unavailable. Her temperature is 40.1°C (104.1°F). Examination shows bilateral conjunctival injections. There are multiple bluish-gray lesions on an erythematous buccal mucosa and soft palate. This patient is at increased risk for which of the following complications?", "answer": "Subacute sclerosing panencephalitis", "options": {"A": "Immune thrombocytopenic purpura", "B": "Subacute sclerosing panencephalitis", "C": "Non-Hodgkin lymphoma", "D": "Transient arrest of erythropoiesis", "E": "Glomerular immune complex deposition\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old man with known end-stage liver disease from alcoholic cirrhosis presents to the emergency department with decreased urinary output and swelling in his lower extremities. His disease has been complicated by ascites and hepatic encephalopathy in the past. Initial laboratory studies show a creatinine of 1.73 mg/dL up from a previous value of 1.12 one month prior. There have been no new medication changes, and no recent procedures performed. A diagnostic paracentesis is performed that is negative for infection, and he is admitted to the hospital for further management and initiated on albumin. Two days later, his creatinine has risen to 2.34 and he is oliguric. Which of the following is the most definitive treatment for this patient's condition?", "answer": "Liver transplantation", "options": {"A": "Cessation of alcohol use", "B": "Peritoneovenous shunt", "C": "Transjugular intrahepatic portosystemic shunt (TIPS)", "D": "Liver transplantation", "E": "Hemodialysis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old machinist presents to his primary care physician with eye problems. The patient states that he has had a mass in his eye that has persisted for the past month. The patient has a past medical history of blepharitis treated with eye cleansing and squamous cell carcinoma of the skin treated with Mohs surgery. His temperature is 99.5°F (37.5°C), blood pressure is 157/102 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for a firm and rubbery nodule palpable inside the patient's left eyelid. Physical exam does not elicit any pain. Which of the following is the most likely diagnosis?", "answer": "Chalazion", "options": {"A": "Chalazion", "B": "Foreign body", "C": "Hordeolum", "D": "Ingrown eyelash follicle", "E": "Meibomian cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 8-year-old boy is brought to the physician for evaluation of developmental delay and recurrent tonic-clonic seizures. There is no family history of seizures or other serious illness. Current medications include risperidone for hyperactivity. He is at the 17th percentile for head circumference. Examination shows protrusion of the mandible, strabismus, and a laughing facial expression. His gait is unsteady. He has a vocabulary of about 200 words and cannot speak in full sentences. Karyotype analysis shows a 46, XY karyotype without chromosomal deletions. Which of the following genetic mechanisms best explains this patient's findings?", "answer": "Uniparental disomy of chromosome 15", "options": {"A": "Chromosome 22q11 microdeletion", "B": "De novo mutation of MECP2 on the X chromosome", "C": "Nondisjunction of chromosome 21 during meiosis I", "D": "Uniparental disomy of chromosome 15", "E": "Trinucleotide repeat in FMR1 gene"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Twelve days after undergoing a cadaveric renal transplant for adult polycystic kidney disease, a 23-year-old man has pain in the right lower abdomen and generalized fatigue. During the past 4 days, he has had decreasing urinary output. Creatinine concentration was 2.3 mg/dL on the second postoperative day. Current medications include prednisone, cyclosporine, azathioprine, and enalapril. His temperature is 38°C (100.4°F), pulse is 103/min, and blood pressure is 168/98 mm Hg. Examination reveals tenderness to palpation on the graft site. Creatinine concentration is 4.3 mg/dL. A biopsy of the transplanted kidney shows tubulitis. C4d staining is negative. Which of the following is the most likely cause of this patient's findings?", "answer": "Allorecognition with T cell activation", "options": {"A": "Drug-induced nephrotoxicity", "B": "Donor T cells from the graft", "C": "Allorecognition with T cell activation", "D": "Irreversible fibrosis of the glomerular vessels", "E": "Preformed cytotoxic antibodies against class I HLA"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man is rushed to the emergency room after he was found unconscious in bed that afternoon. The patient’s wife says he has been confused and irritable for the past several days. She says he has a history of chronic daily alcohol abuse and has been hospitalized multiple times with similar symptoms His temperature is 37°C (98.6°F), the blood pressure is 110/80 mm Hg, the pulse is 90/min, and the respiratory rate is 14/min. On physical examination, the patient is minimally responsive to painful stimuli. His abdomen is distended with positive shifting dullness. Laboratory results are as follows:\nComplete blood count\nHematocrit 35%\nPlatelets 100,000/mm3\nWhite blood cells 5000/mm3\nLiver function studies\nSerum Albumin 2 g/dL\nAlkaline phosphatase (ALP) 200 IU/L\nAspartate aminotransferase (AST) 106 IU/L\nAlanine aminotransferase (ALT) 56 IU/L\nThe patient is admitted to the hospital and started on the appropriate treatment to improve his mental status. Which of the following best describes the mechanism of action of the drug that is most likely used to treat this patient’s symptoms?", "answer": "Decreases pH in the gastrointestinal lumen", "options": {"A": "Prevents the conversion of ammonia into ammonium", "B": "Decreases the colonic concentration of bacteria", "C": "Increases ammonia production and absorption", "D": "Increases pH in the gastrointestinal lumen", "E": "Decreases pH in the gastrointestinal lumen"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 41-year-old homeless man is brought to the emergency department complaining of severe fever, dizziness, and a persistent cough. The patient has a history of long-standing alcohol abuse and has frequently presented to the emergency department with acute alcohol intoxication. The patient states that his cough produces ‘dark brown stuff’ and he provided a sample for evaluation upon request. The patient denies having any other underlying medical conditions and states that he has no other symptoms. He denies taking any medications, although he states that he knows he has a sulfa allergy. On observation, the patient looks frail and severely fatigued. The vital signs include: blood pressure 102/72 mm Hg, pulse 98/min, respiratory rate 15/min, and temperature 37.1°C (98.8°F). Auscultation reveals crackles in the left upper lobe and chest X-ray reveals an infiltrate in the same area. Which of the following is the most appropriate treatment for this patient?", "answer": "Ciprofloxacin", "options": {"A": "Vancomycin", "B": "Piperacillin-tazobactam", "C": "Clindamycin", "D": "Ciprofloxacin", "E": "Trimethoprim-sulfamethoxazole"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old man is brought to the emergency department by ambulance after developing an altered mental state following blunt trauma to the head. The patient was competing at a local mixed martial arts competition when he was struck in the head and lost consciousness. A few minutes later, upon regaining consciousness, he had a progressive decline in mental status. Past medical history is noncontributory. Upon arrival at the hospital, the temperature is 37.0°C (98.6°F), the blood pressure is 145/89 mm Hg, the pulse is 66/min, the respiratory rate is 14/min, and the oxygen saturation is 99% on room air. He is alert now. A noncontrast CT scan is performed, and the result is provided in the image. Which of the following structures is most likely affected in this patient?", "answer": "Middle Meningeal artery", "options": {"A": "Bridging veins", "B": "Middle Meningeal artery", "C": "Subarachnoid space", "D": "Suprasellar cistern", "E": "Ventricular system"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying the efficacy of a new bisphosphonate analog in preventing hip fractures in patients above 60 years of age with risk factors for osteoporosis but no confirmed diagnosis. Participating patients were randomized to either pharmacologic therapy with the new bisphosphonate analog or a placebo. The results show:\nHip fracture No hip fracture\nPharmacologic therapy 3 97\nNo pharmacologic therapy 10 190\nBased on this information, which of the following best represents the proportionate reduction in the risk of hip fractures brought about due to pharmacologic therapy, in comparison to the control group?\"", "answer": "40%", "options": {"A": "3%", "B": "5%", "C": "40%", "D": "2%", "E": "60%"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 44-year-old man presents to the emergency department with weakness. He states that he has felt progressively more weak over the past month. He endorses decreased libido, weight gain, and headaches. His temperature is 97.0°F (36.1°C), blood pressure is 177/108 mmHg, pulse is 80/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for an obese man who appears fatigued. He has abdominal striae, atrophied arms, and limbs with minimal muscle tone. His ECG is notable for a small upward deflection right after the T wave. A fingerstick blood glucose is 225 mg/dL. The patient is treated appropriately and states that he feels much better several hours later. Which of the following treatments could prevent this patient from presenting again with a similar chief complaint?", "answer": "Eplerenone", "options": {"A": "Eplerenone", "B": "Hydrochlorothiazide", "C": "Insulin", "D": "Metoprolol", "E": "Torsemide"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 1-year-old boy is brought to the physician for a well-child examination. He has no history of serious illness. His older sister had an eye disease that required removal of one eye at the age of 3 years. Examination shows inward deviation of the right eye. Indirect ophthalmoscopy shows a white reflex in the right eye and a red reflex in the left eye. The patient is at increased risk for which of the following conditions?", "answer": "Osteosarcoma", "options": {"A": "Neuroblastoma", "B": "Basal cell carcinoma", "C": "Osteosarcoma", "D": "Gastric cancer", "E": "Wilms tumor"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 67-year-old Caucasian female presents to her primary care physician after a screening DEXA scan reveals a T-score of -3.0. Laboratory work-up reveals normal serum calcium, phosphate, vitamin D, and PTH levels. She smokes 1-2 cigarettes per day. Which of the following measures would have reduced this patient's risk of developing osteoporosis?", "answer": "Calcium and vitamin D supplementation", "options": {"A": "Reduced physical activity to decrease the chance of a fall", "B": "Initiating a swimming exercise program three days per week", "C": "Intranasal calcitonin therapy", "D": "Calcium and vitamin D supplementation", "E": "Weight loss"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 43-year-old man is brought to the emergency department 45 minutes after his wife found him on the floor sweating profusely. On arrival, he is lethargic and unable to provide a history. He vomited multiple times on the way to the hospital. His temperature is 37.3°C (99.1°F), pulse is 55/min, respirations are 22/min, and blood pressure is 98/65 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 80%. Examination shows profuse diaphoresis and excessive salivation. He withdraws his extremities sluggishly to pain. The pupils are constricted and reactive. Scattered expiratory wheezing and rhonchi are heard throughout both lung fields. Cardiac examination shows no abnormalities. There are fine fasciculations in the lower extremities bilaterally. Muscle strength is reduced and deep tendon reflexes are 1+ bilaterally. His clothes are soaked with urine and feces. Which of the following is the mechanism of action of the most appropriate initial pharmacotherapy?", "answer": "Competitive antagonism of mACh receptors", "options": {"A": "Urine alkalization", "B": "Enteral binding", "C": "Competitive antagonism of mACh receptors", "D": "Non-selective α-adrenergic antagonism", "E": "Alkaloid emesis-induction"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 82-year-old woman visits her primary care provider complaining of a vague cramping pain on the right side of her abdomen for the past 6 hours. She is also and had an episode of vomiting earlier today and two episodes yesterday. Past medical history includes third-degree heart block, gastroesophageal reflux disease, hypertension, hypothyroidism and chronic cholecystitis with cholelithiasis. She is not a good candidate for cholecystectomy due to cardiac disease and is treated with analgesics and ursodeoxycholic acid. Her medications include chlorthalidone, omeprazole, levothyroxine, and occasional naproxen for pain. Vitals are normal. A supine abdominal X-ray reveals air in the gallbladder and biliary tree (saber sign), small bowel obstruction, and a large a radiolucent gallstone impacted in the small bowel. What is the most likely diagnosis?", "answer": "Gallstone ileus", "options": {"A": "Cholecystitis", "B": "Choledocolithiasis", "C": "Gallstone ileus", "D": "Primary biliary cholangitis", "E": "Small bowel perforation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man with a long-standing history of type 2 diabetes and hypertension managed with lisinopril and metformin presents with itchy skin. He also describes moderate nausea, vomiting, muscle weakness, and fatigue. The vital signs include: temperature 36.8°C (98.2°F), heart rate 98/min, respiratory rate 15/min, blood pressure 135/85 mm Hg, oxygen saturation 100% on room air. Physical exam is notable for pale conjunctivae, pitting edema, and ascites. Laboratory findings are shown below:\nBUN 78 mg/dL\npCO2 25 mm Hg\nCreatinine 7.2 mg/dL\nGlucose 125 mg/dL\nSerum chloride 102 mmol/L\nSerum potassium 6.3 mEq/L\nSerum sodium 130 mEq/L\nTotal calcium 1.3 mmol/L\nMagnesium 1.2 mEq/L\nPhosphate 1.9 mmol/L\nHemoglobin 9.5 g/dL\nMCV 86 μm3\nBicarbonate (HCO3) 10 mmol/L\nShrunken kidneys are identified on renal ultrasound. The doctor explains to the patient that he will likely need dialysis due to his significant renal failure until a renal transplant can be performed. The patient is concerned because he is very busy and traveling a lot for work. What is a potential complication of the preferred treatment?", "answer": "Hypertriglyceridemia", "options": {"A": "Hypoglycemia", "B": "Hypotension", "C": "Muscle cramping", "D": "Hypertriglyceridemia", "E": "Excessive bleeding"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old man is brought to the emergency department because of a 2-week history of abdominal cramps, vomiting, and constipation. He also reports having to urinate frequently and occasional leg pain. He has had similar episodes in the past. He has hypertension and peptic ulcer disease. Current medications include captopril and ranitidine. He appears depressed. Physical examination shows weakness in the extremities. Abdominal examination shows mild epigastric tenderness. There is no rebound or guarding. He has a restricted affect. Laboratory studies show elevated serum parathyroid hormone levels; serum calcium is 14.2 mg/dL. Abdominal ultrasonography shows multiple small calculi in the right kidney. Which of the following is most likely to provide rapid relief in this patient?", "answer": "Normal saline and intravenous calcitonin therapy", "options": {"A": "Intravenous pamidronate therapy", "B": "Reduction of dietary intake of calcium", "C": "Normal saline and intravenous furosemide therapy", "D": "Normal saline and intravenous fentanyl therapy", "E": "Normal saline and intravenous calcitonin therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An obese 37-year-old woman is brought to the emergency department 2 hours after the onset of weakness in her left arm and leg. She fell from the stairs the day prior but did not have any loss of consciousness or nausea after the fall. She travels to Asia regularly on business; her last trip was 4 days ago. She has no history of serious illness. Her only medication is an oral contraceptive. Her temperature is 37.8°C (100°F), pulse is 113/min and regular, and blood pressure is 162/90 mm Hg. Examination shows decreased muscle strength on the left side. Deep tendon reflexes are 4+ on the left. Babinski sign is present on the left. The right lower leg is swollen, erythematous, and tender to palpation. Further evaluation is most likely to show which of the following?", "answer": "Patent foramen ovale", "options": {"A": "Ventricular septal defect", "B": "Carotid artery dissection", "C": "Atrial fibrillation", "D": "Patent foramen ovale", "E": "Atrial myxoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 21-year-old female was brought to the emergency room after losing large amounts of blood from slicing her wrists longitudinally. A few days later, she was interviewed by the psychiatrist and discussed with him why she had tried to kill herself. \"My evil boyfriend of 2 months left me because I never let him leave my side for fear that he would cheat on me and leave me...now I feel so empty without him.\" Which of the following personality disorders does this female most likely have?", "answer": "Borderline", "options": {"A": "Histrionic", "B": "Dependent", "C": "Avoidant", "D": "Borderline", "E": "Paranoid"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old man comes to the physician because of weight gain over the past 3 months. During this period, he has gained 10 kg (22 lb) unintentionally. He also reports decreased sexual desire, oily skin, and sleeping difficulties. There is no personal or family history of serious illness. He has smoked one pack of cigarettes daily for the past 10 years. The patient appears lethargic. His temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 150/90 mm Hg. Physical examination shows central obesity, acne, and thin, easily bruisable skin with stretch marks on the abdomen. There is darkening of the mucous membranes and the skin creases. Examination of the muscles shows atrophy and weakness of proximal muscle groups. His serum glucose concentration is 240 mg/dL. Which of the following findings would most likely be present on imaging?", "answer": "Pituitary microadenoma", "options": {"A": "Pituitary microadenoma", "B": "Decreased thyroid size", "C": "Multiple kidney cysts", "D": "Adrenal carcinoma", "E": "Kidney tumor"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old man is brought to the emergency department by the police after attempting to assault a waiter with a broom. The patient states that the FBI has been following him his entire life and that this man was an agent spying on him. The patient has a past medical history of irritable bowel syndrome. His temperature is 98.0°F (36.7°C), blood pressure is 137/68 mmHg, pulse is 110/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam is deferred due to patient combativeness. The patient is given haloperidol and diphenhydramine. The patient is later seen in his room still agitated. Intraosseous access is obtained. Which of the following is the best next step in management?", "answer": "Urine toxicology", "options": {"A": "Assess for suicidal ideation", "B": "Complete blood count", "C": "Syphilis screening", "D": "Thyroid stimulating hormone level", "E": "Urine toxicology"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 58-year-old woman presents to a physician with a painless swelling behind her right ear, which she noticed 1 month ago. She has no other complaint nor does she have any specific medical condition. On physical examination, her vital signs are stable. An examination of the right post-auricular area shows enlarged lymph nodes, which are non-tender and rubbery in consistency, with normal overlying skin. A detailed general examination reveals the presence of one enlarged axillary lymph node on the left side with similar features. Complete blood counts are within normal limits but atypical lymphocytes are present on the peripheral blood smear. The patient’s serum lactate dehydrogenase level is slightly elevated. Excisional biopsy of the lymph node is performed and histopathological examination of the tissue yields a diagnosis of follicular lymphoma. Further cytogenetic studies reveal that the condition is associated with overexpression of the BCL-2 gene. Which of the following cytogenetic abnormalities is most likely to be present?", "answer": "t(14;18)(q32;q21)", "options": {"A": "t(3;3)(q27;27)", "B": "t(9;14)(p13;q32)", "C": "t(11;14)(q13;q32)", "D": "t(11;18)(q21;q21)", "E": "t(14;18)(q32;q21)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old woman is brought in to the emergency department after her husband noticed that she appeared to be choking on her dinner. He performed a Heimlich maneuver but was concerned that she may have aspirated something. The patient reports a lack of pain and temperature on the right half of her face, as well as the same lack of sensation on the left side of her body. She also states that she has been feeling \"unsteady\" on her feet. On physical exam you note a slight ptosis on the right side. She is sent for an emergent head CT. Where is the most likely location of the neurological lesion?", "answer": "Medulla", "options": {"A": "Internal capsule", "B": "Midbrain", "C": "Pons", "D": "Medulla", "E": "Cervical spinal cord"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2300-g (5-lb 1-oz) male newborn is delivered to a 29-year-old primigravid woman. The mother has HIV and received triple antiretroviral therapy during pregnancy. Her HIV viral load was 678 copies/mL 1 week prior to delivery. Labor was uncomplicated. Apgar scores are 7 and 8 at 1 and 5 minutes respectively. Physical examination of the newborn shows no abnormalities. Which of the following is the most appropriate next step in management of this infant?", "answer": "Administer zidovudine", "options": {"A": "HIV antibody testing", "B": "Administer zidovudine, lamivudine and nevirapine", "C": "Administer lamivudine and nevirapine", "D": "Administer nevirapine", "E": "Administer zidovudine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 33-year-old woman comes to the physician 1 week after noticing a lump in her right breast. Fifteen years ago, she was diagnosed with osteosarcoma of her left distal femur. Her father died of an adrenocortical carcinoma at the age of 41 years. Examination shows a 2-cm, firm, immobile mass in the lower outer quadrant of the right breast. A core needle biopsy of the mass shows adenocarcinoma. Genetic analysis in this patient is most likely to show a defect in which of the following genes?", "answer": "TP53", "options": {"A": "KRAS", "B": "TP53", "C": "BRCA1", "D": "PTEN", "E": "Rb"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old African American man presents to the physician with dyspnea on exertion for the past 2 months. He also has occasional episodes of coughing at night. He says that he has been healthy most of his life. He is a non-smoker and a non-alcoholic. He does not have hypercholesterolemia or ischemic heart disease. His father died due to congestive heart failure. On physical examination, the pulse rate was 116/min, the blood pressure was 164/96 mm Hg, and the respiratory rate was 20/min. Chest auscultation reveals bilateral fine crepitations at the lung bases. A complete diagnostic work-up suggests a diagnosis of hypertension with heart failure due to left ventricular dysfunction. Which of the following drug combinations is most likely to benefit the patient?", "answer": "Isosorbide dinitrate-Hydralazine", "options": {"A": "Amlodipine-Atenolol", "B": "Amlodipine-Valsartan", "C": "Atenolol-Hydrochlorothiazide", "D": "Isosorbide dinitrate-Hydralazine", "E": "Metoprolol-Atorvastatin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 26-year-old woman comes to the physician for a pre-employment examination. She has no complaints. She has a history of polycystic ovarian syndrome. She exercises daily and plays soccer recreationally on the weekends. Her mother was diagnosed with hypertension at a young age. She does not smoke and drinks 2 glasses of wine on the weekends. Her current medications include an oral contraceptive pill and a daily multivitamin. Her vital signs are within normal limits. Cardiac examination shows a grade 1/6 decrescendo diastolic murmur heard best at the apex. Her lungs are clear to auscultation bilaterally. Peripheral pulses are normal and there is no lower extremity edema. An electrocardiogram shows sinus rhythm with a normal axis. Which of the following is the most appropriate next step in management?", "answer": "Transthoracic echocardiogram", "options": {"A": "Exercise stress test", "B": "No further testing", "C": "Transthoracic echocardiogram", "D": "X-ray of the chest", "E": "CT scan of the chest with contrast"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 54-year-old man comes to the emergency department because of burning oral mucosal pain, chest pain, and shortness of breath that started one hour ago. He reports that the pain is worse when swallowing. Two years ago, he was diagnosed with major depressive disorder but does not adhere to his medication regimen. He lives alone and works as a farmer. He smokes 1 pack of cigarettes and drinks 6 oz of homemade vodka daily. The patient is oriented to person, place, and time. His pulse is 95/min, respirations are 18/min, and blood pressure is 130/85 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 95%. Examination of the oropharynx shows profuse salivation with mild erythema of the buccal mucosa, tongue, and epiglottis area. This patient has most likely sustained poisoning by which of the following substances?", "answer": "Potassium hydroxide", "options": {"A": "Potassium hydroxide", "B": "Parathion", "C": "Morphine", "D": "Ethylene glycol", "E": "Amitriptyline"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old man comes to the emergency department with an open wound on his right hand. He states that he got into a bar fight about an hour ago. He appears heavily intoxicated and does not remember the whole situation, but he does recall lying on the ground in front of the bar after the fight. He does not recall any history of injuries but does remember a tetanus shot he received 6 years ago. His temperature is 37°C (98.6°F), pulse is 77/min, and blood pressure is 132/78 mm Hg. Examination shows a soft, nontender abdomen. His joints have no bony deformities and display full range of motion. There is a 4-cm (1.6-in) lesion on his hand with the skin attached only on the ulnar side. The wound, which appears to be partly covered with soil and dirt, is irrigated and debrided by the hospital staff. Minimal erythema and no purulence is observed in the area surrounding the wound. What is the most appropriate next step in management?", "answer": "Application of moist sterile dressing + tetanus vaccine", "options": {"A": "Apposition of wound edges under tension + rifampin", "B": "Surgical treatment with skin graft + tetanus vaccine", "C": "Tension-free apposition of wound edges + sterile dressing", "D": "Application of moist sterile dressing + tetanus vaccine", "E": "Surgical treatment with skin flap + ciprofloxacin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man comes to the physician because of a 3-week history of intermittent burning epigastric pain. His pain improves with antacid use and eating but returns approximately 2 hours following meals. He has a history of chronic osteoarthritis and takes ibuprofen daily. Upper endoscopy shows a deep ulcer located on the posterior wall of the duodenal bulb. This ulcer is most likely to erode into which of the following structures?", "answer": "Gastroduodenal artery", "options": {"A": "Splenic vein", "B": "Pancreatic duct", "C": "Descending aorta", "D": "Gastroduodenal artery", "E": "Transverse colon"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old woman with Wolff-Parkinson-White syndrome presents to her cardiologist’s office for a follow-up visit. She collapsed at her job and made a trip to the emergency department 1 week ago. At that time, she received a diagnosis of atrial fibrillation with rapid ventricular response and hemodynamic instability. While in the emergency department, she underwent direct-current cardioversion to return her heart to sinus rhythm. Her current medications include procainamide. At the cardiologist’s office, her heart rate is 61/min, respiratory rate is 16/min, the temperature is 36.5°C (97.7°F), and blood pressure is 118/60 mm Hg. Her cardiac examination reveals a regular rhythm and a I/VI systolic ejection murmur best heard at the right upper sternal border. An ECG obtained in the clinic is shown. Which of the following is the most appropriate treatment to prevent further episodes of tachyarrhythmia?", "answer": "Refer her for electrophysiology (EP) study and ablation", "options": {"A": "Begin anticoagulation with warfarin", "B": "Begin anticoagulation with dabigatran", "C": "Add verapamil to her medication regimen", "D": "Refer her for electrophysiology (EP) study and ablation", "E": "Refer her for right heart catheterization"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 43-year-old woman is brought to the emergency department for evaluation of worsening abdominal pain that suddenly started 2 hours ago. The patient also has nausea and has vomited twice. She has hypothyroidism, systemic lupus erythematosus, major depressive disorder, and chronic right knee pain. Current medications include levothyroxine, prednisone, fluoxetine, naproxen, and a chondroitin sulfate supplement. She appears distressed. Her temperature is 37.9°C (100.2°F), pulse is 101/min, and blood pressure is 115/70 mm Hg. Examination shows a rigid abdomen with rebound tenderness; bowel sounds are hypoactive. Laboratory studies show a leukocyte count of 13,300/mm3 and an erythrocyte sedimentation rate of 70 mm/h. An x-ray of the chest is shown. Which of the following is the most appropriate next step in management?", "answer": "Exploratory laparotomy", "options": {"A": "Peritoneal lavage", "B": "Esophagogastroduodenoscopy", "C": "Endoscopic retrograde cholangiopancreatography", "D": "Abdominal CT with contrast", "E": "Exploratory laparotomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 67-year-old man is brought to the emergency department because of severe dyspnea and orthopnea for 6 hours. He has a history of congestive heart disease and an ejection fraction of 40%. The medical history is otherwise unremarkable. He appears confused. At the hospital, his blood pressure is 165/110 mm Hg, the pulse is 135/min, the respirations are 48/min, and the temperature is 36.2°C (97.2°F). Crackles are heard at both lung bases. There is pitting edema from the midtibia to the ankle bilaterally. The patient is intubated and admitted to the critical care unit for mechanical ventilation and treatment. Intravenous morphine, diuretics, and nitroglycerine are initiated. Which of the following is the most effective method to prevent nosocomial infection in this patient?", "answer": "Condom catheter placement", "options": {"A": "Condom catheter placement", "B": "Daily urinary catheter irrigation with antimicrobial agent", "C": "Daily oropharynx decontamination with antiseptic agent", "D": "Nasogastric tube insertion", "E": "Suprapubic catheter insertion"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman with no past medical history is post operative day 2 from a cesarean section that resulted in the birth of her first child. She begins to cry when she's told that today's lunch will be gluten-free. Although the patient feels \"exhausted\" and has had trouble sleeping, she deeply desires to return home and take care of her newborn. The patient denies any changes in concentration or suicidal thoughts now or during the pregnancy. What is the diagnosis and likely outcome?", "answer": "Postpartum \"blues\"; her symptoms are likely self-limited", "options": {"A": "Postpartum \"blues\"; her symptoms are likely self-limited", "B": "Postpartum depression; the patient will likely remain depressed for at least six more months", "C": "Major depressive episode; this patient is at high risk of recurrence", "D": "Postpartum psychosis; symptoms will resolve in time, but she needs treatment with antipsychotics, lithium, and/or antidepressants", "E": "Postpartum bipolar disorder; this patient will likely have future bipolar episodes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old man comes to the physician because of a hypopigmented skin lesion on his finger. He first noticed it 4 weeks ago after cutting his finger with a knife while preparing food. He did not feel the cut. For the past week, he has also had fever, fatigue, and malaise. He has not traveled outside the country since he immigrated from India to join his family in the United States 2 years ago. His temperature is 38.7°C (101.7°F). Physical examination shows a small, healing laceration on the dorsal aspect of the left index finger and an overlying well-defined, hypopigmented macule with raised borders. Sensation to pinprick and light touch is decreased over this area. Which of the following is the most likely causal pathogen of this patient's condition?", "answer": "Mycobacterium leprae", "options": {"A": "Pseudomonas aeruginosa", "B": "Epidermophyton floccosum", "C": "Mycobacterium leprae", "D": "Leishmania donovani", "E": "Malassezia furfur"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man presents to his primary care provider with progressive right foot swelling, redness, and malaise. He reports seeing a blister on his forefoot several months ago after he started using new work boots. He has dressed the affected area daily with bandages; however, healing has not occurred. He has a history of type 2 diabetes mellitus and stage 2 chronic kidney disease. He has smoked 20 to 30 cigarettes daily for the past 25 years. Vital signs are a temperature of 38.1°C (100.58°F), blood pressure of 110/70 mm Hg, and pulse of 102/minute. On physical examination, there is a malodorous right foot ulcer overlying the first metatarsophalangeal joint. Fluctuance and erythema extend 3 cm beyond the ulcer border. Moderate pitting edema is notable over the remaining areas of the foot and ankle. Which of the following is the best initial step for this patient?", "answer": "Antibiotics and supportive care", "options": {"A": "Graded compression stockings", "B": "Superficial swabs", "C": "Antibiotics and supportive care", "D": "Endovascular intervention", "E": "Minor amputation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old woman presents to the doctor's office seeking evaluation for her recurrent urinary tract infections. She admits to urinary frequency and a burning sensation when urinating. This is her 3rd UTI in the past year. She has a history of generalized anxiety disorder for which she takes paroxetine. She is sexually active and has had multiple partners during the past year. The patient’s blood pressure is 116/72 mm Hg, the heart rate is 76/min, the respiratory rate is 12/min and the temperature is 36.8°C (98.2°F). On physical examination, she is alert and oriented to time, place, and person. There is no murmur. Her lungs are clear to auscultation bilaterally. Her abdomen is soft and non-tender to palpation. The distance from the urethra to anus is shorter than the average female her age. Urinalysis and urine culture results are provided:\nUrine culture results  200 CFUs of Escherichia coli (normal < 100 if symptomatic)\nLeukocyte esterase positive\nWBC 50-100 cells/hpf\nNitrite positive\nRBC 3 cells/hpf\nEpithelial cells 2 cells/hpf\npH 5.2 (normal 4.5–8)\nWhich of the following recommendations would be most appropriate for this patient?", "answer": "Trimethoprim-sulfamethoxazole, and urinating before and after intercourse", "options": {"A": "Trimethoprim-sulfamethoxazole, and urinating before and after intercourse", "B": "Urinating before and after intercourse", "C": "Cephalexin", "D": "Cranberry juice", "E": "Trimethoprim-sulfamethoxazole"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A primary care physician who focuses on treating elderly patients is researching recommendations for primary, secondary, and tertiary prevention. She is particularly interested in recommendations regarding aspirin, as she has several patients who ask her if they should take it. Of the following, which patient should be started on lifelong aspirin as monotherapy for atherosclerotic cardiovascular disease prevention?", "answer": "A 63-year-old male with a history of a transient ischemic attack", "options": {"A": "A 75-year-old male who had a drug-eluting coronary stent placed 3 days ago", "B": "A 67-year-old female who has diabetes mellitus and atrial fibrillation", "C": "A 45-year-old female with no health problems", "D": "An 83-year-old female with a history of a hemorrhagic stroke 1 year ago without residual deficits", "E": "A 63-year-old male with a history of a transient ischemic attack"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 60-year-old man presents with breathlessness for the past 3 months. His symptoms have been getting progressively worse during this time. He denies any history of cough, fever, or chest pain. He works at a local shipyard and is responsible for installing the plumbing aboard the vessels. His past medical history is significant for hypertension for which he takes metoprolol every day. He denies smoking and any illicit drug use. His pulse is 74/min, respiratory rate is 14/min, blood pressure is 130/76 mm Hg, and temperature is 36.8°C (98.2°F). Physical examination is significant for fine bibasilar crackles at the end of inspiration without digital clubbing. Which of the following additional findings would most likely be present in this patient?", "answer": "Decreased diffusion lung capacity of CO", "options": {"A": "Decreased diffusion lung capacity of CO", "B": "Decreased pulmonary arterial pressure", "C": "Increased pulmonary capillary wedge pressure", "D": "Increased residual lung volume", "E": "Reduced FEV1/FVC ratio"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-year-old boy is presented to the pediatrician due to poor weight gain and easy fatigability. His mother states that the patient barely engages in any physical activity as he becomes short of breath easily. The prenatal and birth histories are insignificant. Past medical history includes a few episodes of upper respiratory tract infection that were treated successfully. The patient is in the 10th percentile for weight and 40th percentile for height. The vital signs include: heart rate 122/min and respirations 32/min. Cardiac auscultation reveals clear lungs and a grade 2/6 holosystolic murmur loudest at the left lower sternal border. The remainder of the physical examination is negative for clubbing, cyanosis, and peripheral edema. Which of the following is the most likely diagnosis in this patient?", "answer": "Ventricular septal defect (VSD)", "options": {"A": "Patent ductus arteriosus (PDA)", "B": "Atrial septal defect (ASD)", "C": "Ventricular septal defect (VSD)", "D": "Coarctation of aorta", "E": "Tetralogy of Fallot (TOF)"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "On cardiology service rounds, your team sees a patient admitted with an acute congestive heart failure exacerbation. In congestive heart failure, decreased cardiac function leads to decreased renal perfusion, which eventually leads to excess volume retention. To test your knowledge of physiology, your attending asks you which segment of the nephron is responsible for the majority of water absorption. Which of the following is a correct pairing of the segment of the nephron that reabsorbs the majority of all filtered water with the means by which that segment absorbs water?", "answer": "Proximal convoluted tubule via passive diffusion following ion reabsorption", "options": {"A": "Distal convoluted tubule via aquaporin channels", "B": "Collecting duct via aquaporin channels", "C": "Thick ascending loop of Henle via passive diffusion following ion reabsorption", "D": "Proximal convoluted tubule via passive diffusion following ion reabsorption", "E": "Distal convoluted tubule via passive diffusion following ion reabsorption"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old male presents to his primary care physician for a check-up. He reports that he visited an urgent care clinic last week for seasonal allergies; he was instructed at that encounter to follow-up with his primary care doctor because his blood pressure measured at that time was 162/88. He denies any bothersome symptoms and reports that he feels well overall. The patient denies any past history of medical problems other than cholecystitis that was surgically treated over 30 years ago. On further probing through review of symptoms, the patient reports that he often feels 'shaky' when performing tasks; he reports that his hands shake whenever he attempts to eat or drink something and also when he writes. Vital signs obtained at the visit are as follows: T 37.2 C, HR 88, BP 154/96, RR 20, SpO2 98%. A second blood pressure reading 10 minutes after the first set of vitals shows a blood pressure of 150/94. Physical examination is overall unremarkable and does not reveal a resting tremor in either hand; however, when the patient is asked to pick up a pen to fill out insurance paperwork, you note a fine shaking in his right hand. Which of the following is the next best step in the management of this patient?", "answer": "Start propranolol", "options": {"A": "Instruction to begin a diet and exercise regimen", "B": "Referral to a neurologist", "C": "Initiate levodopa", "D": "Prescribe losartan", "E": "Start propranolol"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 68-year-old man presents with a 3-month history of difficulty starting urination, weak stream, and terminal dribbling. The patient has no history of serious illnesses and is not under any medications currently. The patient’s father had prostate cancer at the age of 58 years. Vital signs are within normal range. Upon examination, the urinary bladder is not palpable. Further examination reveals normal anal sphincter tone and a bulbocavernosus muscle reflex. Digital rectal exam (DRE) shows a prostate size equivalent to 2 finger pads with a hard nodule and without fluctuance or tenderness. The prostate-specific antigen (PSA) level is 5 ng/mL. Image-guided biopsy indicates prostate cancer. MRI shows tumor confined within the prostate. Radionuclide bone scan reveals no abnormalities. Which of the following interventions is the most appropriate next step in the management of this patient?", "answer": "Radiation therapy + androgen deprivation therapy", "options": {"A": "Chemotherapy + androgen deprivation therapy", "B": "Finasteride + tamsulosin", "C": "Radiation therapy + androgen deprivation therapy", "D": "Radical prostatectomy + chemotherapy", "E": "Radical prostatectomy + radiation therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old woman recently underwent kidney transplantation for end-stage renal disease. Her early postoperative period was uneventful, and her serum creatinine is lowered from 4.3 mg/dL (preoperative) to 2.5 mg/dL. She is immediately started on immunosuppressive therapy. On postoperative day 7, she presents to the emergency department (ED) because of nausea, fever, abdominal pain at the transplant site, malaise, and pedal edema. The vital signs include: pulse 106/min, blood pressure 167/96 mm Hg, respirations 26/min, and temperature 40.0°C (104.0°F). The surgical site shows no signs of infection. Her urine output is 250 mL over the past 24 hours. Laboratory studies show:\nHematocrit 33%\nWhite blood cell (WBC) count 6700/mm3\nBlood urea 44 mg/dL\nSerum creatinine 3.3 mg/dL\nSerum sodium 136 mEq/L\nSerum potassium 5.6 mEq/L\nAn ultrasound of the abdomen shows collection of fluid around the transplanted kidney with moderate hydronephrosis. Which of the following initial actions is the most appropriate?", "answer": "Continue with an ultrasound-guided biopsy of the transplanted kidney", "options": {"A": "Continue with an ultrasound-guided biopsy of the transplanted kidney", "B": "Consider hemodialysis", "C": "Start on pulse steroid treatment or OKT3", "D": "Re-operate and remove the failed kidney transplant", "E": "Supportive treatment with IV fluids, antibiotics, and antipyretics"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 40-year-old African American female with a past obstetrical history of para 5, gravida 4 with vaginal birth 4 weeks ago presents with the chief complaint of shortness of breath. On examination, the patient has an elevated jugular venous pressure, an S3, respiratory crackles, and bilateral pedal edema. Chest X-ray shows bronchial cuffing, fluid in the fissure, and a pleural effusion. Her ejection fraction is 38% on echocardiogram. Which of the following is a characteristic of the most likely diagnosis?", "answer": "Ventricular dilatation", "options": {"A": "Conduction disorder", "B": "Hypertrophy", "C": "Infarction", "D": "Pericarditis", "E": "Ventricular dilatation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 59-year-old man presents to a clinic with exertional chest pain for the past several months. He says the pain is central in his chest and relieved with rest. The physical examination is unremarkable. An electrocardiogram is normal, but an exercise tolerance test revealed ST-segment depression in chest leads V1-V4. He is prescribed nitroglycerin to be taken in the first half of the day. Which of the following statements best describes the reason behind the timing of this medication?", "answer": "To avoid nitrate tolerance", "options": {"A": "To prevent collapse", "B": "To avoid nitrate headache", "C": "More effective in patients with angina due to anemia", "D": "To prevent methemoglobinemia", "E": "To avoid nitrate tolerance"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 39-year-old woman comes to the physician for difficulty sleeping and poor concentration at work. She sleeps with the lights turned on and wakes up frequently during the night with palpitations and profuse sweating. Three weeks ago she was sexually assaulted in her car. Since the assault she has avoided using her car and only uses public transportation. She also has nightmares of her attacker. She has been sent home from work for yelling at her coworkers. She has Hashimoto thyroiditis. Current medications include levothyroxine. She has been treated for pelvic inflammatory disease in the past. She has tried alcohol and melatonin to help her sleep. Mental status examination shows a depressed mood and a negative affect. Which of the following is the most likely diagnosis?", "answer": "Acute stress disorder", "options": {"A": "Acute stress disorder", "B": "Adjustment disorder", "C": "Post-traumatic stress disorder", "D": "Persistent complex bereavement disorder", "E": "Adverse effect of medication\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 1-day-old infant presents to the office because the mother noticed “blood” in the diaper of her child. She has brought the diaper with her which shows a small reddish marking. The pregnancy was without complications, as was the delivery. The patient presents with no abnormal findings on physical examination. The laboratory analysis shows uric acid levels in the blood to be 5 mg/dL. Which of the following should be the next step in management?", "answer": "No therapy is required", "options": {"A": "Allopurinol", "B": "Febuxostat", "C": "No therapy is required", "D": "Rasburicase", "E": "Sodium bicarbonate"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the emergency department because of a sudden loss of vision in his left eye for 2 hours. He has no pain. He had a similar episode 1 month ago which lasted only seconds. He has no history of a headache or musculoskeletal pain. He has had ischemic heart disease for 8 years and hypertension and diabetes mellitus for 13 years. His medications include metoprolol, aspirin, insulin, lisinopril, and atorvastatin. He has smoked 1 pack of cigarettes for 39 years. The vital signs include: blood pressure 145/98 mm Hg, pulse 86/min, respirations 16/min, and temperature 36.7°C (98.1°F). Physical examination of the left eye shows a loss of light perception. After illumination of the right eye and conceptual constriction of the pupils, illumination of the left eye shows pupillary dilation. A fundoscopy image is shown. Which of the following best explains these findings?", "answer": "Central retinal artery occlusion", "options": {"A": "Central retinal artery occlusion", "B": "Demyelinating optic neuritis", "C": "Retinal detachment", "D": "Temporal arteritis", "E": "Wet macular degeneration"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 29-year-old woman presents with low mood and tearfulness on most days for the past 4 weeks. She says that she has been struggling to cope with her life and feels that everything that is going wrong is her fault. She also says that there are nights when she cries herself to sleep as the burden of the whole day is too overwhelming for her. In the last 3 weeks, she cannot recall a day when she felt interested in going out and participating in her daily activities. She also says she doesn’t seem to have much energy and feels fatigued all day. She has lost her appetite and feels that she is losing weight. Over the past month, she also reports experiencing frequent and often unbearable migraine headaches. No significant past medical history. The patient has prescribed a drug for her symptoms which is known to be cardiotoxic and may result in ECG changes. Which of the following is the mechanism of action of the drug most likely prescribed to this patient?", "answer": "Inhibits the uptake of serotonin and norepinephrine at the presynaptic terminal", "options": {"A": "Blocks the reuptake of serotonin, increasing its concentration in the synaptic cleft", "B": "Non-selectively inhibits monoamine oxidase A and B", "C": "Stimulates the release of norepinephrine and dopamine in the presynaptic terminal", "D": "Inhibits the uptake of serotonin and norepinephrine at the presynaptic terminal", "E": "Acts as an antagonist at the dopamine and serotonin receptors"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 46-year-old man comes to the clinic complaining of abdominal pain for the past month. The pain comes and goes and is the most prominent after meals. He reports 1-2 episodes of black stools in the past month, a 10-lbs weight loss, fevers, and a skin rash on his left arm. A review of systems is negative for any recent travel, abnormal ingestion, palpitations, nausea/vomiting, diarrhea, or constipation. Family history is significant for a cousin who had liver failure in his forties. His past medical history is unremarkable. He is sexually active with multiple partners and uses condoms intermittently. He admits to 1-2 drinks every month and used to smoke socially during his teenage years. His laboratory values are shown below:\n\nSerum:\nNa+: 138 mEq/L\nCl-: 98 mEq/L\nK+: 3.8 mEq/L\nHCO3-: 26 mEq/L \nBUN: 10 mg/dL \nGlucose: 140 mg/dL\nCreatinine: 2.1 mg/dL\nThyroid-stimulating hormone: 3.5 µU/mL\nCa2+: 10 mg/dL\nAST: 53 U/L\nALT: 35 U/L\n\nHBsAg: Positive\nAnti-HBc: Positive\nIgM anti-HBc: Positive\nAnti-HBs: Negative\n\nWhat findings would you expect to find in this patient?", "answer": "Segmental ischemic necrosis of various ages at the mesenteric arteries", "options": {"A": "Diffuse bridging fibrosis and regenerative nodules at the liver", "B": "PAS-positive macrophages in the intestinal lamina propria", "C": "Presence of anti-proteinase 3", "D": "Segmental ischemic necrosis of various ages at the mesenteric arteries", "E": "Ulcers at the gastric mucosa"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is studying the effects of zinc deprivation on cancer cell proliferation. It is hypothesized that because zinc is known to be a component of transcription factor motifs, zinc deprivation will result in slower tumor growth. To test this hypothesis, tumor cells are cultured on media containing low and high concentrations of zinc. During the experiment, a labeled oligonucleotide probe is used to identify the presence of a known transcription factor. The investigator most likely used which of the following laboratory techniques?", "answer": "Southwestern blot", "options": {"A": "Western blot", "B": "Northern blot", "C": "PCR", "D": "ELISA", "E": "Southwestern blot"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 64-year-old female presents with acute right wrist pain after she lost her balance while reaching overhead and fell from standing height. Her right wrist radiographs shows a fracture of her right distal radius. A follow-up DEXA bone density scan is performed and demonstrates a T-score of -3.5 at the femoral neck and spine. Her medical history is significant for hypertension, for which she is not currently taking any medication. She has not had a previous fracture. Which of the following antihypertensive agents would be preferred in this patient?", "answer": "Hydrochlorothiazide", "options": {"A": "Hydrochlorothiazide", "B": "Furosemide", "C": "Lisinopril", "D": "Propranolol", "E": "Amlodipine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 18-month-old boy is brought to the physician because of walking difficulties. His mother says that he cannot walk unless he is supported. She has also noted orange, sandy residues in his diapers. Over the past year, she has frequently caught him pulling his toenails and chewing the tips of his fingers. Examination shows scarring of his fingertips. Muscle tone is decreased in the upper and lower extremities. He cannot pick up and hold small objects between the tips of the index finger and the thumb. The most appropriate pharmacotherapy for this patient's condition inhibits which of the following conversions?", "answer": "Xanthine to urate\n\"", "options": {"A": "Hypoxanthine to inosine monophosphate", "B": "Ornithine to citrulline", "C": "Orotate to uridine monophosphate", "D": "Adenosine to inosine", "E": "Xanthine to urate\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old man, otherwise healthy, has a routine CBC done prior to donating blood for the first time. The results are as follows:\nHemoglobin 10.8 g/dL\nMean corpuscular volume (MCV) 82 μm3\nMean corpuscular hemoglobin concentration (MCHC) 42%\nReticulocyte count 3.2%\nWhite blood cell count 8,700/mm3\nPlatelet count 325,000/mm3\nThe patient is afebrile and his vital signs are within normal limits. On physical examination, his spleen is just palpable. A peripheral blood smear is shown in the exhibit (see image). A direct antiglobulin test (DAT) is negative. Which of the following best describes the etiology of this patient’s most likely diagnosis?", "answer": "Inherited membrane abnormality of red cells", "options": {"A": "Bone marrow hypocellularity", "B": "Inherited membrane abnormality of red cells", "C": "Microangiopathic process", "D": "Immune-mediated hemolysis", "E": "Oxidant hemolysis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old man is brought to the emergency department because of severe retrosternal pain radiating to the back and left shoulder for 4 hours. The pain began after attending a farewell party for his coworker at a local bar. He had 3–4 episodes of nonbilious vomiting before the onset of the pain. He has hypertension. His father died of cardiac arrest at the age of 55 years. He has smoked one pack of cigarettes daily for the last 23 years and drinks 2–3 beers daily. His current medications include amlodipine and valsartan. He appears pale. His temperature is 37° C (98.6° F), pulse is 115/min, and blood pressure is 90/60 mm Hg. There are decreased breath sounds over the left base and crepitus is palpable over the thorax. Abdominal examination shows tenderness to palpation in the epigastric region; bowel sounds are normal. Laboratory studies show:\nHemoglobin 16.5 g/dL\nLeukocyte count 11,100/mm3\nSerum\nNa+ 133 mEq/L\nK+ 3.2 mEq/L\nCl- 98 mEq/L\nHCO3- 30 mEq/L\nCreatinine 1.4 mg/dL\nAn ECG shows sinus tachycardia with left ventricular hypertrophy. Intravenous fluid resuscitation and antibiotics are begun. Which of the following is the most appropriate test to confirm the diagnosis in this patient?\"", "answer": "CT scan of the chest", "options": {"A": "Esophagogastroduodenoscopy", "B": "Aortography", "C": "CT scan of the chest", "D": "Abdominal ultrasound", "E": "Transthoracic echocardiography\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4430-g (9-lb 10-oz) male newborn is delivered at term to a 27-year-old woman, gravida 2, para 1. The second stage of labor was prolonged and required vacuum-assisted vaginal delivery. Apgar scores are 9 and 10 at 1 and 5 minutes, respectively. Examination of the neonate 2 hours later shows a soft, nonpulsatile swelling over the left parietal bone that does not cross suture lines. Vital signs are within normal limits. The pupils are equal and reactive to light. The lungs are clear to auscultation. Heart sounds are normal. The spine is normal. Which of the following is the most likely diagnosis?", "answer": "Cephalohematoma", "options": {"A": "Lipoma", "B": "Cephalohematoma", "C": "Subgaleal hemorrhage", "D": "Epidermoid cyst", "E": "Encephalocele"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 19-year-old university student presents to the student clinic with painful joints. He states that over the past week his right wrist has become increasingly stiff. This morning he noticed pain and stiffness in his left ankle and left knee. The patient has celiac disease and takes a daily multivitamin. He says he is sexually active with multiple male and female partners. He smokes marijuana but denies intravenous drug abuse. He recently traveled to Uganda to volunteer at a clinic that specialized in treating patients with human immunodeficiency virus (HIV). He also went on an extended hiking trip last week in New Hampshire. Physical exam reveals swelling of the right wrist and a warm, swollen, erythematous left knee. The left Achilles tendon is tender to palpation. There are also multiple vesicopustular lesions on the dorsum of the right hand. No penile discharge is appreciated. Arthrocentesis of the left knee is performed. Synovial fluid results are shown below:\n\nSynovial fluid:\nAppearance: Cloudy\nLeukocyte count: 40,000/mm^3 with neutrophil predominance\n\nGram stain is negative. A synovial fluid culture is pending. Which of the following is the patient’s most likely diagnosis?", "answer": "Disseminated gonococcal infection", "options": {"A": "Dermatitis herpetiformis", "B": "Disseminated gonococcal infection", "C": "Lyme disease", "D": "Reactive arthritis", "E": "Septic arthritis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 56-year-old man comes to the physician because of lower back pain for the past 2 weeks. The pain is stabbing and shooting in quality and radiates down the backs of his legs. It began when he was lifting a bag of cement at work. The pain has been getting worse, and he has started to notice occasional numbness and clumsiness while walking. He has hypertension and peripheral artery disease. Medications include hydrochlorothiazide and aspirin. His temperature is 37°C (98.6°F), pulse is 82/min, and blood pressure is 133/92 mm Hg. Peripheral pulses are palpable in all four extremities. Neurological examination shows 5/5 strength in the upper extremities and 3/5 strength in bilateral foot dorsiflexion. Sensation to light touch is diminished bilaterally over the lateral thigh area and the inner side of lower legs. Passive raising of either the right or left leg causes pain radiating down the ipsilateral leg. Which of the following is the most appropriate next step in management?", "answer": "MRI of the lumbar spine", "options": {"A": "X-ray of the lumbar spine", "B": "Erythrocyte sedimentation rate", "C": "MRI of the lumbar spine", "D": "Therapeutic exercise regimen", "E": "PSA measurement"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 12-year-old boy is brought to the emergency department after a motor vehicle collision. He was being carpooled to school by an intoxicated driver and was involved in a high velocity head-on collision. The patient is otherwise healthy and has no past medical history. His temperature is 99.2°F (37.3°C), blood pressure is 80/45 mmHg, pulse is 172/min, respirations are 36/min, and oxygen saturation is 100% on room air. A FAST exam demonstrates free fluid in Morrison pouch. The patient’s parents arrive and state that they are Jehovah’s witnesses. They state they will not accept blood products for their son but will allow him to go to the operating room to stop the bleeding. Due to poor understanding and a language barrier, the parents are also refusing IV fluids as they are concerned that this may violate their religion. The child is able to verbalize that he agrees with his parents and does not want any treatment. Which of the following is the best next treatment for this patient?", "answer": "Blood products and emergency surgery", "options": {"A": "Blood products and emergency surgery", "B": "IV fluids alone as surgery is too dangerous without blood product stabilization", "C": "IV fluids and emergency surgery", "D": "IV fluids and vasopressors followed by emergency surgery", "E": "Observation and monitoring and obtain a translator"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old male presents to his primary care physician with upper abdominal pain. He reports a 3-month history of mild epigastric pain that improves with meals. He has lost 15 pounds since his symptoms started. His past medical history is notable for gynecomastia in the setting of a prolactinoma for which he underwent surgical resection over 10 years prior. He has a 15-pack-year smoking history, a history of heroin abuse, and is on methadone. His family history is notable for parathyroid adenoma in his father. His temperature is 98.8°F (37.1°C), blood pressure is 125/80 mmHg, pulse is 78/min, and respirations are 18/min. This patient’s symptoms are most likely due to elevations in a substance with which of the following functions?", "answer": "Promote gastric mucosal growth", "options": {"A": "Decrease gastric acid secretion", "B": "Decrease gastrin secretion", "C": "Increase pancreatic bicarbonate secretion", "D": "Increase pancreatic exocrine secretion", "E": "Promote gastric mucosal growth"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old male with a history of hypertension presents to his primary care physician complaining of multiple episodes of chest pain, palpitations, and syncope. Episodes have occurred twice daily for the last week, and he is asymptomatic between episodes. Electrocardiogram reveals a narrow-complex supraventricular tachycardia. He is treated with diltiazem. In addition to its effects on cardiac myocytes, on which of the following channels and tissues would diltiazem also block depolarization?", "answer": "L-type Ca channels in smooth muscle", "options": {"A": "L-type Ca channels in skeletal muscle", "B": "L-type Ca channels in smooth muscle", "C": "P-type Ca channels in Purkinje fibers", "D": "N-type Ca channels in the peripheral nervous system", "E": "T-type Ca channels in bone"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old G2P1 female at 30 weeks gestation presents to the emergency department with complaints of vaginal bleeding and severe abdominal pain. She states that she began feeling poorly yesterday with a stomach-ache, nausea, and vomiting. She first noted a small amount of spotting this morning that progressed to much larger amounts of vaginal bleeding with worsened abdominal pain a few hours later, prompting her to come to the emergency department. Her previous pregnancy was without complications, and the fetus was delivered at 40 weeks by Cesarean section. Fetal heart monitoring shows fetal distress with late decelerations. Which of the following is a risk factor for this patient's presenting condition?", "answer": "Hypertension", "options": {"A": "Hyperlipidemia", "B": "Hypertension", "C": "Patient age", "D": "Prior Cesarean section", "E": "Singleton pregnancy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 48-year-old woman presents to her family practitioner complaining of tremulousness of both hands for the past few years that have deteriorated over the past 7 months. She sometimes spills coffee while holding a full cup. She is a receptionist and her symptoms have led to difficulties with typing at work. She denies weight loss, diarrhea, fatigue, blurring of vision, walking difficulties, and heat intolerance. The past medical history is significant for well-controlled bronchial asthma. She does not smoke or use illicit drugs, but she drinks one cup of coffee daily. She drinks alcohol only socially and has noticed a decrease in her tremors afterward. She reports that her father had a head tremor, and her mother had hyperthyroidism. The patient is oriented to person, place, time and situation. On physical examination, the eye movements are normal and there is no nystagmus. She has a prominent rhythmic tremor of both hands that increase when hands are stretched with abducted fingers. The muscle strength, tone, and deep tendon reflexes are normal in all 4 limbs. The sensory examination and gait are normal. The laboratory test results are as follows:\nHemoglobin  14.8 g/dL\nLeukocytes 5,500/mm3\nPlatelets 385,000/mm3\nBUN  18 mg/dL\nCreatinine 0.9 mg/dL\nNa+ 143 mmol/L\nK+ 4.2 mmol/L\nWhich of the following is the most appropriate management for this patient? ", "answer": "Primidone", "options": {"A": "Clonazepam", "B": "Levodopa/Carbidopa", "C": "Primidone", "D": "Propranolol", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 29-year-old man presents to his primary care provider after complaining of a rash on his penis. He describes it as small painless growths that have developed over the past several months. They have slowly increased in size over time. His medical history is unremarkable. He has had several sexual partners and uses condoms inconsistently. He describes himself as having generally good health and takes no medication. On physical exam, his vital signs are normal. There are multiple cauliflower-like papular eruptions just under the glans penis. They are tan-pink and raised. Examination of the scrotum, perineum, and anus shows no abnormalities. There is no inguinal lymphadenopathy. The remainder of the physical exam shows no abnormalities. Which of the following is the most appropriate initial management?", "answer": "Cryotherapy", "options": {"A": "Cryotherapy", "B": "Interferon ɑ", "C": "Laser therapy", "D": "Quadrivalent vaccine", "E": "Topical imiquimod"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 19-year-old man presents with painful oral ulcers and rash. He says that his symptoms started 1 week ago with a low-grade fever, malaise, and cough. Then, 3 days ago, he noted small painful red bumps on his hands and feet, which quickly worsened and spread to involve his extremities and upper torso. At the same time, multiple painful oral ulcers appeared, which have not improved. He denies any trouble breathing, pruritus, hemoptysis, hematochezia, or similar symptoms in the past. Past medical history is significant for a recent methicillin-resistant staphylococcus aureus (MRSA) skin infection 2 weeks ago secondary to a laceration on his left leg for which he has been taking trimethoprim-sulfamethoxazole. No other current medications. The patient is afebrile, and his vital signs are within normal limits. Physical examination reveals multiple raised, erythematous, circular papules averaging 1–2 cm in diameter with a central bulla, as shown in the exhibit (see image below). The cutaneous lesions occupy < 10% of his total body surface area (BSA). Nicolsky sign is negative. Multiple mucosal erosions are noted in the oral cavity. Generalized lymphadenopathy is present. A well-healing laceration is present on the left leg with no evidence of drainage or fluctuance. A cutaneous punch biopsy of one of the lesions is performed. Which of the following histopathologic features would most likely be found on this patient’s biopsy?", "answer": "Rich dermal inflammatory infiltrate, predominantly composed of CD4+ T cells", "options": {"A": "Scant dermal inflammatory infiltrate, predominantly composed of macrophages and dendritic cells", "B": "Rich dermal inflammatory infiltrate, predominantly composed of CD4+ T cells", "C": "Presence of intradermal blister and separation of suprabasal epidermal cells from basal cells", "D": "Presence of a subepidermal blister and a polymorphous inflammatory infiltrate with an eosinophilic predominance", "E": "Mucin deposition in the dermal layer"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old woman presents to her gynecologist's office with complaints of frequent hot flashes and significant sweating episodes, which affect her sleep at night. She complains that she has to change her clothes in the middle of the night because of the sweating events. She also complains of irritability, which is affecting her relationships with her husband and daughter. She reports vaginal itchiness and pain with intercourse. Her last menstrual period was eight months ago. She was diagnosed with breast cancer 15 years ago, which was promptly detected and cured successfully via mastectomy. The patient is currently interested in therapies to help control her symptoms. Which of the following options is the most appropriate medical therapy in this patient for symptomatic relief?", "answer": "Low-dose vaginal estrogen", "options": {"A": "Conjugated estrogen orally", "B": "Conjugated estrogen and medroxyprogesterone acetate orally", "C": "Low-dose vaginal estrogen", "D": "Transdermal estradiol-17B patch", "E": "This patient is not a candidate for hormone replacement therapy."}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An investigator is studying a hereditary defect in the mitochondrial enzyme succinyl-CoA synthetase. In addition to succinate, the reaction catalyzed by this enzyme produces a molecule that is utilized as an energy source for protein translation. This molecule is also required for which of the following conversion reactions?", "answer": "Oxaloacetate to phosphoenolpyruvate", "options": {"A": "Acetaldehyde to acetate", "B": "Fructose-6-phosphate to fructose-1,6-bisphosphate", "C": "Glucose-6-phosphate to 6-phosphogluconolactone", "D": "Oxaloacetate to phosphoenolpyruvate", "E": "Pyruvate to acetyl-CoA"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old man comes to the physician because of a 1-month history of fatigue, low-grade fevers, and cough productive of blood-tinged sputum. He has type 2 diabetes mellitus and chronic kidney disease and underwent kidney transplantation 8 months ago. His temperature is 38.9°C (102.1°F) and pulse is 98/min. Examination shows rhonchi in the right lower lung field. An x-ray of the chest shows a right-sided lobar consolidation. A photomicrograph of specialized acid-fast stained tissue from a blood culture is shown. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Exposure to contaminated soil", "options": {"A": "Poor oral hygiene", "B": "Exposure to contaminated soil", "C": "Exposure to contaminated air-conditioning unit", "D": "Sharing of unsterile IV needles", "E": "Crowded living situation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-day-old male newborn born at 39 weeks' gestation is brought to the physician because of yellowing of his skin. His mother received no prenatal care and the delivery was uncomplicated. She has no history of serious medical illness and has one other son who is healthy. Physical examination shows jaundice, hepatomegaly, and decreased muscle tone. Laboratory studies show:\nHemoglobin 9.4 g/dL\nMaternal blood type O\nPatient blood type O\nSerum\nBilirubin\nTotal 16.3 mg/dL\nDirect 0.4 mg/dL\nWhich of the following is the most likely underlying cause of this patient's condition?\"", "answer": "IgG antibody formation against Rh antigen", "options": {"A": "Glucose-6-phosphate dehydrogenase deficiency", "B": "IgM antibody formation against A and B antigens", "C": "Biliary duct malformation", "D": "UDP-glucuronosyltransferase deficiency", "E": "IgG antibody formation against Rh antigen"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old man is brought to the emergency department by a neighbor with signs of altered mental status. He was found 6 hours ago stumbling through his neighbor's bushes and yelling obscenities. The neighbor helped him home, but found him again 1 hour later slumped over on his driveway in a puddle of vomit. He is oriented to self, but not to place or time. His vitals are as follows: temperature, 36.9°C (98.5°F); pulse, 82/min; respirations, 28/min; and blood pressure, 122/80 mm Hg. Cardiopulmonary examination indicates no abnormalities. He is unable to cooperate for a neurological examination. Physical examination reveals muscle spasms involving his arms and jaw. Laboratory studies show:\nNa+ 140 mEq/L\nK+ 5.5 mEq/L\nCI- 101 mEq/L\nHCO3- 9 mEq/L\nUrea nitrogen 28 mg/dL\nCreatinine 2.3 mg/dL\nGlucose 75 mg/dL\nCalcium 7.2 mg/dL\nOsmolality 320 mOsm/kg\nThe calculated serum osmolality is 294 mOsm/kg. The arterial blood gas shows a pH of 7.25 and a lactate level of 3.2 mmol/L. Urine examination shows oxalate crystals and the absence of ketones. What is the most appropriate treatment indicated for this patient experiencing apparent substance toxicity?", "answer": "Fomepizole", "options": {"A": "Ethanol", "B": "Fomepizole", "C": "Hydroxocobalamin", "D": "Methylene blue", "E": "N-acetyl cysteine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 23-year-old woman from Texas is transferred to the intensive care unit after delivering a child at 40 weeks gestation. The pregnancy was not complicated, and there was some blood loss during the delivery. The patient was transferred for severe hypotension refractory to IV fluids and vasopressors. She is currently on norepinephrine and vasopressin with a mean arterial pressure of 67 mmHg. Her past medical history is notable only for a recent bout of asthma treated with albuterol and a prednisone taper over 5 days for contact dermatitis. Physical exam is notable for abnormally dark skin for a Caucasian woman. The patient states she feels extremely weak. However, she did experience breastmilk letdown and was able to breastfeed her infant. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 127 mEq/L\nCl-: 92 mEq/L\nK+: 6.1 mEq/L\nHCO3-: 22 mEq/L\nBUN: 20 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the most likely diagnosis?", "answer": "Primary adrenal insufficiency", "options": {"A": "Acute kidney injury", "B": "Mycobacteria tuberculosis", "C": "Primary adrenal insufficiency", "D": "Sheehan syndrome", "E": "Withdrawal from prednisone use"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old man is evaluated for abdominal discomfort he has had for the past 6 days and fever for the past 2 weeks. He also notes that his right upper abdomen is bothering him. He states that he does not drink alcohol or use illicit drugs. His medical history is insignificant and family history is negative for any liver disease. On physical examination, his temperature is 38.0°C (100.4°F), blood pressure is 120/80 mm Hg, pulse rate is 102/min, and respiratory rate is 22/min. He is alert and oriented. Scleral icterus and hepatomegaly are noted. Laboratory results are as follows:\nAnti-hepatitis A IgM positive\nAnti-hepatitis A IgG negative\nHepatitis B surface Ag negative\nHepatitis B surface AB negative\nAlanine aminotransferase 1544 U/L\nAspartate aminotransferase 1200 U/L\nWhich of the following transcription factors is required for the B cells to differentiate into plasma cells in this patient?", "answer": "B lymphocyte induced maturation protein 1 (BLIMP1)", "options": {"A": "Paired box protein 5 (PAX5)", "B": "B cell lymphoma 6 (BCL6)", "C": "Microphthalmia-associated transcription factor (MITF)", "D": "Metastasis-associated 1 family, member 3 (MTA-3)", "E": "B lymphocyte induced maturation protein 1 (BLIMP1)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 53-year-old woman presents to her primary care provider complaining of fatigue for the last several months. She reports feeling tired all day, regardless of her quality or quantity of sleep. On further questioning, she has also noted constipation and a 4.5 kg (10 lb) weight gain. She denies shortness of breath, chest pain, lightheadedness, or blood in her stool. At the doctor’s office, the vital signs include: pulse 58/min, blood pressure 104/68 mm Hg, and oxygen saturation 98% on room air. The physical exam shows only slightly dry skin. The complete blood count (CBC) is within normal limits. Which of the following best describes the pathogenesis of this patient's condition?", "answer": "Autoimmune attack on endocrine tissue", "options": {"A": "Autoimmune attack on endocrine tissue", "B": "Bone marrow failure", "C": "Chronic blood loss", "D": "Iatrogenesis", "E": "Nutritional deficiency"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 67-year-old woman is brought to the emergency department for evaluation of fever, chest pain, and a cough that has produced a moderate amount of greenish-yellow sputum for the past 2 days. During this period, she has had severe malaise, chills, and difficulty breathing. Her past medical history is significant for hypertension, hypercholesterolemia, and type 2 diabetes, for which she takes lisinopril, atorvastatin, and metformin. She has smoked one pack of cigarettes daily for 20 years. Her vital signs show her temperature is 39.0°C (102.2°F), pulse is 110/min, respirations are 33/min, and blood pressure is 143/88 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 94%. Crackles are heard on auscultation of the right upper lobe. Laboratory studies show a leukocyte count of 12,300/mm3, an erythrocyte sedimentation rate of 60 mm/h, and urea nitrogen of 15 mg/dL. A chest X-ray is shown. Which of the following is the most appropriate next step to manage this patient’s symptoms?", "answer": "Inpatient treatment with azithromycin and ceftriaxone", "options": {"A": "ICU admission and administration of ampicillin-sulbactam and levofloxacin", "B": "Inpatient treatment with azithromycin and ceftriaxone", "C": "Inpatient treatment with cefepime, azithromycin, and gentamicin", "D": "Inpatient treatment with cefepime, azithromycin, and gentamicin", "E": "Outpatient treatment with moxifloxacin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 68-year-old woman is brought to the emergency department because of a 3-day history of nausea, anorexia, polyuria, and confusion. Her only medication is acetaminophen, which she takes daily for back pain that started 6 weeks ago. Physical examination shows conjunctival pallor. She is oriented to person but not to time or place. Laboratory studies show a hemoglobin concentration of 9.3 g/dL, a serum calcium concentration of 13.8 mg/dL, and a serum creatinine concentration of 2.1 mg/dL. Her erythrocyte sedimentation rate is 65 mm/h. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Overproliferation of plasma cells", "options": {"A": "Excessive intake of calcium", "B": "Overproliferation of plasma cells", "C": "Ectopic release of PTHrP", "D": "Decreased renal excretion of calcium", "E": "Excess PTH secretion from parathyroid glands"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old man with alcohol use disorder is brought to the emergency department because of sudden-onset blurry vision, severe upper abdominal pain, and vomiting that started one day after he drank a bottle of paint thinner. Physical examination shows epigastric tenderness without rebound or guarding. Ophthalmologic examination shows a visual acuity of 20/200 bilaterally despite corrective lenses. Arterial blood gas analysis on room air shows:\npH 7.21\nSodium 135 mEq/L\nChloride 103 mEq/L\nBicarbonate 13 mEq/L\nAn antidote with which of the following mechanisms of action is the most appropriate therapy for this patient's condition?\"", "answer": "Inhibition of alcohol dehydrogenase", "options": {"A": "Activation of acetyl-CoA synthetase", "B": "Inhibition of acetaldehyde dehydrogenase", "C": "Inhibition of acetyl-CoA synthetase", "D": "Activation of acetaldehyde dehydrogenase", "E": "Inhibition of alcohol dehydrogenase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "One week after delivery, a 3550-g (7-lb 13-oz) newborn has multiple episodes of bilious vomiting and abdominal distention. He passed urine 14 hours after delivery and had his first bowel movement 3 days after delivery. He was born at term to a 31-year-old woman. Pregnancy was uncomplicated and the mother received adequate prenatal care. His temperature is 37.1°C (98.8°F), pulse is 132/min, and respirations are 50/min. Examination shows a distended abdomen. Bowel sounds are hypoactive. Digital rectal examination shows a patent anus and an empty rectum. The remainder of the examination shows no abnormalities. An x-ray of the abdomen is shown. Which of the following is the underlying cause of these findings?", "answer": "Defective migration of neural crest cells", "options": {"A": "Defective migration of neural crest cells", "B": "Disruption of blood flow to the fetal jejunum", "C": "Mutation in the CFTR gene", "D": "Abnormal rotation of the intestine", "E": "Failed recanalization of the fetal duodenum"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 35-year-old man presents with erectile dysfunction. Past medical history is significant for diabetes mellitus type 1 diagnosed 25 years ago, managed with insulin, and for donating blood 6 months ago. The patient denies any history of smoking or alcohol use. He is afebrile, and his vital signs are within normal limits. Physical examination shows a bronze-colored hyperpigmentation on the dorsal side of the arms bilaterally. Nocturnal penile tumescence is negative. Routine basic laboratory tests are significant for a moderate increase in glycosylated hemoglobin and hepatic enzymes. Which of the following is the most likely diagnosis in this patient?", "answer": "Hemochromatosis", "options": {"A": "Hemochromatosis", "B": "Psychogenic erectile dysfunction", "C": "Wilson's disease", "D": "Porphyria cutanea tarda", "E": "Chronic hepatitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old woman sees her family doctor for a follow-up appointment to discuss her imaging studies. She previously presented with chest pain and shortness of breath for the past 2 months. Her CT scan shows a 3.5 cm mass in the lower lobe of her right lung. The mass has irregular borders. Saddle/hilar lymph nodes are enlarged. No distant metastases are identified with PET imaging. The patient has been a smoker for over 35 years (1.5 packs per day), but she has recently quit. This patient is referred to the Pulmonary Diseases Center. What is the most effective step in appropriately managing her case?", "answer": "Tissue biopsy", "options": {"A": "Tissue biopsy", "B": "Sputum cytology", "C": "CT scan in 3 months", "D": "Paclitaxel", "E": "Radiotherapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A researcher discovers a new inhibitor for 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase that she believes will be more effective than current drugs. The compound she discovers uses the same mechanism of inhibiting the target enzyme as current drugs of this class; however, it has fewer off target effects and side effects. Therefore, she thinks that this drug can be used at higher concentrations. In order to study the effects of this compound on the enzyme, she conducts enzyme kinetics studies. Specifically, she plots the substrate concentration of the enzyme on the x-axis and its initial reaction velocity on the y-axis. She then calculates the Michaelis-Menten constant (Km) as well as the maximum reaction velocity (Vmax) of the enzyme. Compared to values when studying the enzyme alone, what will be the values seen after the inhibitor is added?", "answer": "Higher Km and same Vmax", "options": {"A": "Higher Km and lower Vmax", "B": "Higher Km and same Vmax", "C": "Same Km and higher Vmax", "D": "Same Km and lower Vmax", "E": "Same Km and same Vmax"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 37-year-old G1P1 woman gives birth to a male infant at 36 weeks gestation. The patient had an uncomplicated Caesarean delivery and gave birth to a 6-pound infant. The patient has a past medical history of cocaine and heroine use but states she quit 8 years ago. She also suffers from obesity and type II diabetes mellitus. Her blood sugar is well-controlled with diet and exercise alone during the pregnancy. Her temperature is 98.4°F (36.9°C), blood pressure is 167/102 mmHg, pulse is 90/min, respirations are 13/min, and oxygen saturation is 98% on room air. Laboratory values for her infant are ordered as seen below.\n\nHemoglobin: 22 g/dL\nHematocrit: 66%\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\n\nWhich of the following is the most likely cause of this infant's laboratory abnormalities?", "answer": "Maternal hypertension", "options": {"A": "Advanced maternal age", "B": "Caesarean section delivery", "C": "Gestational age", "D": "Maternal diabetes", "E": "Maternal hypertension"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old patient presents to your office with rhinorrhea that you believe to be viral in origin. He respectfully requests treatment with antibiotics, and he demonstrates an understanding of the risks, benefits, and alternatives to treatment. His mental status is intact, and you believe him to have full decision-making capacity. Which of the following is the best course of action?", "answer": "Deny the patient's request", "options": {"A": "Prescribe ciprofloxacin", "B": "Prescribe amoxicillin", "C": "Prescribe zidovudine", "D": "Refer the patient to an infectious disease specialist", "E": "Deny the patient's request"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old man is discovered unconscious by local police while patrolling in a park. He is unresponsive to stimulation. Syringes were found scattered around him. His heart rate is 70/min and respiratory rate is 6/min. Physical examination reveals a disheveled man with track marks on both arms. His glasgow coma scale is 8. Pupillary examination reveals miosis. An ambulance is called and a reversing agent is administered. Which of the following is most accurate regarding the reversal agent most likely administered to this patient?", "answer": "Results in acute withdrawal", "options": {"A": "Results in acute withdrawal", "B": "Has a short half-life", "C": "Works on dopamine receptors", "D": "Is a non-competitive inhibitor", "E": "Can be given per oral"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 35-year-old pregnant woman gives birth to a baby at term. The antepartum course was uneventful. She was compliant with all prenatal examinations and was given a prophylactic tetanus vaccine. While performing the neonatal examination, the pediatrician reports Apgar scores of 9 and 10 at 1 and 5 min, respectively. The pediatrician notices that the baby has ambiguous genitalia and blood pressure that is high for a neonate. The notable laboratory results are as follows:\nRenin 0.4 nmoL/L/h\nAldosterone 70 pmoL/L\nCortisol 190 nmoL/L\nSerum creatinine 1.0 mg/dL\nSex hormones are higher than the normal values at this age. Which of the following is responsible for the neonate's hypertension?", "answer": "Increased amount of 11-deoxycorticosterone", "options": {"A": "Increased concentration of sex hormones", "B": "Decreased amount of aldosterone", "C": "Increased amount of 11-deoxycorticosterone", "D": "Decreased amount of cortisol", "E": "Decreased angiotensin response"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 64-year-old woman comes to the physician because of a 7-month history of abdominal discomfort, fatigue, and a 6.8-kg (15-lb) weight loss. Physical examination shows generalized pallor and splenomegaly. Laboratory studies show anemia with pronounced leukocytosis and thrombocytosis. Cytogenetic analysis shows a BCR-ABL fusion gene. A drug with which of the following mechanisms of action is most appropriate for this patient?", "answer": "Tyrosine kinase inhibitor", "options": {"A": "Tyrosine kinase inhibitor", "B": "Topoisomerase II inhibitor", "C": "Monoclonal anti-CD20 antibody", "D": "Monoclonal anti-HER-2 antibody", "E": "Ribonucleotide reductase inhibitor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man is brought to the emergency room by his daughter with complaints of a productive cough, rust-colored sputum, and fever for 1 week. He denies any breathlessness or chest pain. The past medical history is unremarkable. The vital signs include a pulse rate of 103/min, respiratory rate of 34/min, and blood pressure of 136/94 mm Hg, with an axillary temperature of 38.9°C (102.0°F). The SaO2 is 86% on room air. The chest examination revealed a dull percussion note and coarse crepitations over the left mid-chest. The patient was admitted to the medical unit and intravenous antibiotics were started. He responded well, but after 2 days an elevated temperature was noted. The patient deteriorated and he was transferred to the intensive care unit. A few days later, his temperature was 39.0°C (103.2°F), the respiratory rate was 23/min, the blood pressure was 78/56 mm Hg, and the SaO2 was 78%. He also had a delayed capillary refill time with a pulse of 141/min. Blood was drawn for the white cell count, which revealed a total count of 17,000/µL. The attending physician decides to begin therapy for the low blood pressure, which brings about a change in the cardiovascular physiology, as shown in the graph with the post-medication represented by a dashed line. Which of the following medications was most likely administered to the patient?", "answer": "Norepinephrine", "options": {"A": "Captopril", "B": "Phenoxybenzamine", "C": "Low-dose dopamine", "D": "Isoproterenol", "E": "Norepinephrine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 64-year-old man presents with a complaint of prominent stiffness in his legs which is causing a difficulty in ambulation. He is not able to relax his trunk area and has frequent, painful muscle spasms. He denies diplopia, swallowing difficulties, and urinary or bowel problems. He has a medical history of stage IV lung cancer. He has received 4 sessions of chemotherapy. The neurological examination reveals an increased generalized muscle tone. He has a spastic gait with exaggerated lumbar lordosis. The needle electromyography (EMG) studies show continuous motor unit activity that persists at rest. Which paraneoplastic antibody is most likely associated with the symptoms of this patient?", "answer": "Amphiphysin", "options": {"A": "Amphiphysin", "B": "Anti-Hu", "C": "Anti-Ri", "D": "Glutamic acid decarboxylase", "E": "Voltage-gated calcium channel"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man comes to the physician for the evaluation of difficulty swallowing that has worsened over the past year. He also reports some hoarseness and generalized bone, muscle, and joint pain. During the past six months, he has had progressive constipation and two episodes of kidney stones. He also reports recurrent episodes of throbbing headaches, diaphoresis, and palpitations. He does not smoke or drink alcohol. He takes no medications. His vital signs are within normal limits. Physical examination and an ECG show no abnormalities. Laboratory studies show calcium concentration of 12 mg/dL, phosphorus concentration of 2 mg/dL, alkaline phosphatase concentration of 100 U/L, and calcitonin concentration of 11 pg/mL (N < 8.8). Ultrasonography of the neck shows hypoechoic thyroid lesions with irregular margins and microcalcifications. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Altered RET proto-oncogene expression", "options": {"A": "Mutated NF1 gene", "B": "Exposure to ionizing radiation", "C": "Deleted VHL gene", "D": "Altered RET proto-oncogene expression", "E": "Disrupted menin protein function"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old boy presents with bilateral conjunctivitis and pharyngitis. The patient’s mother says that symptoms acutely onset 3 days ago and include itchy red eyes, a low-grade fever, and a sore throat. She says that the patient recently attended a camp where other kids were also ill and were completely healthy before going. No significant past medical history. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Adenovirus", "options": {"A": "Enterovirus", "B": "Metapneumovirus", "C": "Influenza virus", "D": "Rhinovirus", "E": "Adenovirus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to the emergency department after the sudden onset of a rash that started on the head and progressed to the trunk and extremities. Over the past week, he has had a runny nose, a cough, and red, crusty eyes. He recently immigrated with his family from Yemen and immunization records are unavailable. The patient appears malnourished. His temperature is 40.0°C (104°F). Examination shows generalized lymphadenopathy and a blanching, partially confluent maculopapular exanthema. Administration of which of the following is most likely to improve this patient's condition?", "answer": "Retinol", "options": {"A": "Valacyclovir", "B": "Penicillin V", "C": "Retinol", "D": "Live-attenuated vaccine", "E": "Intravenous immunoglobulin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old man presents with a 1-year history of resting tremor and clumsiness in his right hand. He says his symptoms are progressively worsening and are starting to interfere with his work. He has no significant past medical history and is not currently taking any medications. The patient denies any smoking history, alcohol, or recreational drug use. Family history is significant for his grandfather, who had a tremor, and his father, who passed away at a young age. Neither his brother nor his sister have tremors. Vital signs include: pulse 70/min, respiratory rate 15/min, blood pressure 124/70 mm Hg, and temperature 36.7°C (98.1°F). Physical examination reveals decreased facial expression, hypophonia, resting tremor in the right hand, rigidity in the upper limbs, and normal deep tendon reflexes. No abnormalities of posture are seen and gait is normal except for decreased arm swing on the right. The remainder of the exam is unremarkable. Which of the following medications would be most effective in treating this patient’s movement problems and his depression?", "answer": "Selegiline", "options": {"A": "Benztropine", "B": "Selegiline", "C": "Entacapone", "D": "Bromocriptine", "E": "Levodopa/carbidopa"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year-old woman presented to her PCP with one week of difficulty falling asleep, despite having good sleep hygiene. She denies changes in her mood, weight loss, and anhedonia. She has had difficulty concentrating and feels tired throughout the day. Recently, she was fired from her previous job. What medication would be most helpful for this patient?", "answer": "Zolpidem", "options": {"A": "Quetiapine", "B": "Zolpidem", "C": "Diphenhydramine", "D": "Diazepam", "E": "Citalopram"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old male patient is brought into the emergency department by emergency medical services. The patient has a history of schizophrenia and is on medication per his mother. His mother also states that the dose of his medication was recently increased, though she is not sure of the specific medication he takes. His vitals are HR 110, BP 170/100, T 102.5, RR 22. On exam, he cannot respond to questions and has rigidity. His head is turned to the right and remains in that position during the exam. Labs are significant for a WBC count of 14,000 cells/mcL, with a creatine kinase (CK) level of 3,000 mcg/L. What is the best treatment for this patient?", "answer": "Dantrolene", "options": {"A": "Diazepam", "B": "Morphine", "C": "Dantrolene", "D": "Valproate", "E": "Lamotrigine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old woman presents to the clinic for a several-month history of heat intolerance. She lives in a small apartment with her husband and reports that she always feels hot and sweaty, even when their air conditioning is on high. On further questioning, she's also had a 4.5 kg (10 lb) unintentional weight loss. The vital signs include: heart rate 102/min and blood pressure 150/80 mm Hg. The physical exam is notable for warm and slightly moist skin. She also exhibits a fine tremor in her hands when her arms are outstretched. Which of the following laboratory values is most likely low in this patient?", "answer": "Thyroid-stimulating hormone", "options": {"A": "Calcitonin", "B": "Glucose", "C": "Triiodothyronine (T3)", "D": "Thyroxine (T4)", "E": "Thyroid-stimulating hormone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old man presents to the emergency room with a complaint of lower abdominal pain that started about 5 hours ago. The pain was initially located around the umbilicus but later shifted to the right lower abdomen. It is a continuous dull, aching pain that does not radiate. He rates the severity of his pain as 7/10. He denies any previous history of similar symptoms. The vital signs include heart rate 100/min, respiratory rate 20/min, temperature 38.0°C (100.4°F), and blood pressure 114/77 mm Hg. On physical examination, there is severe right lower quadrant tenderness on palpation. Deep palpation of the left lower quadrant produces pain in the right lower quadrant. Rebound tenderness is present. The decision is made to place the patient on antibiotics and defer surgery. Two days later, his abdominal pain has worsened. Urgent computed tomography (CT) scan reveals new hepatic abscesses. The complete blood count result is given below:\nHemoglobin 16.2 mg/dL\nHematocrit 48%\nLeukocyte count 15,000/mm³\nNeutrophils 69%\nBands 3%\nEosinophils 1%\nBasophils 0%\nLymphocytes 24%\nMonocytes 3%\nPlatelet count 380,000/mm³\nWhich of the following complications has this patient most likely experienced?", "answer": "Pylephlebitis", "options": {"A": "Pylephlebitis", "B": "Intestinal obstruction", "C": "Peritonitis", "D": "Perforation", "E": "Appendiceal abscess"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 37-year-old man comes to the physician for a follow-up examination. He is being evaluated for high blood pressure readings that were incidentally recorded at a routine health maintenance examination 1 month ago. He has no history of serious illness and takes no medications. His pulse is 88/min and blood pressure is 165/98 mm Hg. Physical examination shows no abnormalities. Serum studies show:\nNa+ 146 mEq/L\nK+ 3.0 mEq/L\nCl- 98 mEq/L\nGlucose 77 mg/dL\nCreatinine 0.8 mg/dL\nHis plasma aldosterone concentration (PAC) to plasma renin activity (PRA) ratio is 36 (N = < 10). A saline infusion test fails to suppress aldosterone secretion. A CT scan of the adrenal glands shows bilateral adrenal abnormalities. An adrenal venous sampling shows elevated PACs from bilateral adrenal veins. Which of the following is the most appropriate next step in management?\"", "answer": "Eplerenone therapy", "options": {"A": "Amiloride therapy", "B": "Propranolol therapy", "C": "Unilateral adrenalectomy", "D": "Eplerenone therapy", "E": "Bilateral adrenalectomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 73-year-old woman is brought to the emergency department because of a 1-day history of skin lesions. Initially, she experienced pain in the affected areas, followed by discoloration of the skin and formation of blisters. Four days ago, the patient was started on a new medication by her physician after failed cardioversion for intermittent atrial fibrillation. She lives alone and does not recall any recent falls or trauma. She has hypertension treated with metoprolol and diabetes mellitus treated with insulin. Her temperature is 37°C (98.6°F), pulse is 108/min and irregularly irregular, and blood pressure is 145/85 mm Hg. Examination of her skin shows well-circumscribed purple maculae, hemorrhagic blisters, and areas of skin ulceration over the breast, lower abdomen, and gluteal region. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Deficiency of a natural anticoagulant", "options": {"A": "Mutation in clotting factor V", "B": "Deficiency of a natural anticoagulant", "C": "Damaged aortic valve", "D": "Formation of antibodies against a platelet antigen", "E": "Major neurocognitive disorder\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old man presents with multiple painful ulcers on his penis. He says that the ulcers all appeared suddenly at the same time 3 days ago. He reports that he is sexually active with multiple partners and uses condoms inconsistently. He is afebrile and his vital signs are within normal limits. Physical examination reveals multiple small shallow ulcers with an erythematous base and without discharge. There is significant inguinal lymphadenopathy present. Which of the following is the most likely etiologic agent of this patient’s ulcers?", "answer": "Herpes simplex virus", "options": {"A": "Human papillomavirus", "B": "Chlamydia trachomatis", "C": "Treponema pallidum", "D": "Haemophilus ducreyi", "E": "Herpes simplex virus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 71-year-old male is admitted to the hospital with a Staphylococcal aureus infection of his decubitus ulcers. He is diabetic and has a body mass index of 45. His temperature is 37°C (98.6°F), respirations are 15/min, pulse is 67/min and blood pressure is 122/98 mm Hg. The nurse is monitoring his blood glucose and records it as 63 mg/dL. She then asks the resident on call if the patient should receive glargine insulin as ordered seeing his glucose levels. Which of the following would be the most appropriate response by the resident?", "answer": "Yes, glargine insulin is a long-acting insulin and should still be given to control his blood glucose over the next 24 hours.", "options": {"A": "Yes, glargine insulin is a long-acting insulin and should still be given to control his blood glucose over the next 24 hours.", "B": "No, glargine insulin should not be given during an episode of hypoglycemia as it will further lower blood glucose.", "C": "No, glargine insulin was probably ordered in error as it is not recommended in type 2 diabetes.", "D": "No, due to his S. aureus infection he is more likely to have low blood glucose and glargine insulin should be held until he has recovered.", "E": "No, glargine insulin should be stopped and replaced with lispro insulin until his blood glucose increases."}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 10-year-old boy presents to your office with puffy eyes. The patient's mother states that his eyes seem abnormally puffy and thinks he may have an eye infection. Additionally, he had a sore throat a week ago which resolved with over the counter medications. The mother also thought that his urine was darker than usual and is concerned that blood may be present. His temperature is 99.5°F (37.5°C), blood pressure is 107/62 mmHg, pulse is 100/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for bilateral periorbital edema. Cranial nerves are grossly intact bilaterally. Which of the following is the most likely finding on renal biopsy for this patient", "answer": "Sub-epithelial electron dense deposits on electron microscopy", "options": {"A": "Alternating thickening and thinning of basement membrane with splitting of the lamina densa", "B": "Linear Ig deposits along the basement membrane", "C": "No abnormalities", "D": "Podocyte fusion on electron microscopy", "E": "Sub-epithelial electron dense deposits on electron microscopy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man presents to his primary care provider after noticing increasing fatigue over the past several weeks. He now becomes short of breath after going up 1 flight of stairs. He was previously healthy and has not seen a doctor for several years. He denies any fever or changes to his bowel movements. On exam, his temperature is 98.8°F (37.1°C), blood pressure is 116/76 mmHg, pulse is 74/min, and respirations are 14/min. On basic labs, his hemoglobin is found to be 9.6 g/dL and MCV is 75 fL. Fecal blood testing is positive for occult blood. Imaging is notable for a mass in the cecum that is partially obstructing the lumen, as well as several small lesions in the liver. Which of the following structures is most at risk for involvement in this patient’s disease?", "answer": "Superior mesenteric vein", "options": {"A": "Inferior mesenteric vein", "B": "Inferior rectal vein", "C": "Right gonadal vein", "D": "Right renal vein", "E": "Superior mesenteric vein"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old woman is brought to the emergency department by her roommate because of bizarre behavior and incoherent talkativeness for the past week. Her roommate reports that the patient has been rearranging the furniture in her room at night and has ordered a variety of expensive clothes online. The patient says she feels “better than ever” and has a lot of energy. She had absence seizures as a child and remembers that valproate had to be discontinued because it damaged her liver. She has been otherwise healthy and is not taking any medication. She is sexually active with her boyfriend. She does not smoke, drink alcohol, or use illicit drugs. Physical and neurologic examinations show no abnormalities. Her pulse is 78/min, respirations are 13/min, and blood pressure is 122/60 mm Hg. Mental status examination shows pressured and disorganized speech, flight of ideas, lack of insight, and affective lability. Which of the following is the best initial step before deciding on a therapy for this patient's condition?", "answer": "Obtain TSH, β-hCG, and serum creatinine concentration", "options": {"A": "Obtain CBC, liver function studies, and beta-HCG", "B": "Assess for suicidal ideation and obtain echocardiography", "C": "Obtain TSH, β-hCG, and serum creatinine concentration", "D": "Perform urine drug testing and begin cognitive behavior therapy", "E": "Obtain BMI, HbA1c, lipid levels, and prolactin levels"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 36-year-old woman comes to the physician because of a 12-month history of upper abdominal pain. The pain is worse after eating, which she reports as 7 out of 10 in intensity. Over the last year, she has also had nausea, heartburn, and multiple episodes of diarrhea with no blood or mucus. Eight months ago, she underwent an upper endoscopy, which showed several ulcers in the gastric antrum, the pylorus, and the duodenum, as well as thick gastric folds. The biopsies from these ulcers were negative for H. pylori. Current medications include pantoprazole and over-the-counter antacids. She appears anxious. Vital signs are within normal limits. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and there is tenderness to palpation in the epigastric and umbilical areas. Test of the stool for occult blood is positive. A repeat upper endoscopy shows persistent gastric and duodenal ulceration with minimal bleeding. Which of the following is the most appropriate next step in diagnosis?", "answer": "Fasting serum gastrin level", "options": {"A": "Secretin stimulation test", "B": "Urea breath test", "C": "24-hour esophageal pH monitoring", "D": "Fasting serum gastrin level", "E": "CT scan of the abdomen and pelvis\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old Caucasian woman comes to the clinic with complaints of fatigability and persistent headaches for the last month. Her headache is dull, encompassing her whole head, and has been getting worse lately. She has associated diplopia and progressively diminishing peripheral vision. She also complains of difficulty losing weight despite trying to control her diet and exercising regularly. She weighs 91 kg (200 lb) at present and reports having gained 9 kg (20 lb) in the past month. Past medical history is insignificant. Blood pressure is 110/70 mm Hg, pulse rate is 60/min, respiratory rate is 12/min, temperature is 36.5°C (97.7°F). Physical examination shows bilateral papilledema. There is some pedal edema and her deep tendon reflexes are slow. CT scan shows suprasellar calcifications. Laboratory studies show:\nNa+ 140 mEq/L\nK+ 3.8 mEq/L\nSerum calcium 9.5 mg/dL\nTSH 0.05 U/mL\nFree T4 0.2 ng/mL\nWhich of the following is the most probable diagnosis?", "answer": "Craniopharyngioma", "options": {"A": "Craniopharyngioma", "B": "Primary hypothyroidism", "C": "Optic nerve atrophy", "D": "Glioblastoma", "E": "Pituitary adenoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old man is brought to the emergency department by his roommate 20 minutes after being discovered unconscious at home. On arrival, he is unresponsive to painful stimuli. His pulse is 65/min, respirations are 8/min, and blood pressure is 110/70 mm Hg. Pulse oximetry shows an oxygen saturation of 75%. Despite appropriate lifesaving measures, he dies. The physician suspects that he overdosed. If the suspicion is correct, statistically, the most likely cause of death is overdose with which of the following groups of drugs?", "answer": "Opioid analgesics", "options": {"A": "Opioid analgesics", "B": "Amphetamines", "C": "Heroin", "D": "Antidepressants", "E": "Acetaminophen"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman presents with fever, chills, nausea, and dysuria. She says her symptoms started 4 days ago and have progressively worsened. Her past medical history is significant for recurrent UTIs for the past 6 months and for diabetes mellitus type 2, diagnosed 5 years ago and treated with metformin. Her vital signs include: temperature 39.5°C (103.1°F), blood pressure 100/70 mm Hg, pulse 90/min, and respiratory rate 23/min. On physical examination, moderate right costovertebral angle tenderness is noted. Laboratory findings are significant for the following:\nWBC 9,500/mm3\nRBC 4.20 x 106/mm3\nHematocrit 41.5%\nHemoglobin 13.0 g/dL\nPlatelet count 225,000/mm3\nUrinalysis:\nColor Dark yellow\nClarity Turbid\npH 5.5\nSpecific gravity 1.021\nGlucose None\nKetones None\nNitrites Positive\nLeukocyte esterase Positive\nBilirubin Negative\nUrobilirubin 0.6 mg/dL\nProtein Trace\nBlood None\nWBC 25/hpf\nBacteria Many\nUrine culture and sensitivities are pending. Which of the following is the best next step in the management of this patient?", "answer": "Admit for IV antibiotic therapy", "options": {"A": "Contrast MRI of the abdomen and pelvis", "B": "Discharge with outpatient antibiotic therapy", "C": "Admit for prompt percutaneous nephrostomy", "D": "Renal ultrasound", "E": "Admit for IV antibiotic therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old woman presents with progressive vision loss in her right eye and periorbital pain for 5 days. She says that she has also noticed weakness, numbness, and tingling in her left leg. Her vital signs are within normal limits. Neurological examination shows gait imbalance, positive Babinski reflexes, bilateral spasticity, and exaggerated deep tendon reflexes in the lower extremities bilaterally. FLAIR MRI is obtained and is shown in the image. Which of the following is the most likely cause of this patient’s condition?", "answer": "Multiple sclerosis", "options": {"A": "Acute disseminated encephalomyelitis", "B": "Amyotrophic lateral sclerosis", "C": "Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephaly (CADASIL)", "D": "Lead intoxication", "E": "Multiple sclerosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-month-old girl is brought to the emergency department by her parents after she appeared to have a seizure at home. On presentation, she no longer has convulsions though she is still noted to be lethargic. She was born through uncomplicated vaginal delivery and was not noted to have any abnormalities at the time of birth. Since then, she has been noted by her pediatrician to be falling behind in height and weight compared to similarly aged infants. Physical exam reveals an enlarged liver, and laboratory tests reveal a glucose of 38 mg/dL. Advanced testing shows that a storage molecule present in the cells of this patient has abnormally short outer chains. Which of the following enzymes is most likely defective in this patient?", "answer": "Debranching enzyme", "options": {"A": "Branching enzyme", "B": "Debranching enzyme", "C": "Glucose-6-phosphatase", "D": "Hepatic phosphorylase", "E": "Muscle phosphorylase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A scientist is studying the mechanisms by which bacteria become resistant to antibiotics. She begins by obtaining a culture of vancomycin-resistant Enterococcus faecalis and conducts replicate plating experiments. In these experiments, colonies are inoculated onto a membrane and smeared on 2 separate plates, 1 containing vancomycin and the other with no antibiotics. She finds that all of the bacterial colonies are vancomycin resistant because they grow on both plates. She then maintains the bacteria in liquid culture without vancomycin while she performs her other studies. Fifteen generations of bacteria later, she conducts replicate plating experiments again and finds that 20% of the colonies are now sensitive to vancomycin. Which of the following mechanisms is the most likely explanation for why these colonies have become vancomycin sensitive?", "answer": "Plasmid loss", "options": {"A": "Gain of function mutation", "B": "Plasmid loss", "C": "Point mutation", "D": "Loss of function mutation", "E": "Viral infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman presents to clinic in emotional distress. She states she has been unhappy for the past couple of months and is having problems with her sleep and appetite. Additionally, she reports significant anxiety regarding thoughts of dirtiness around the house. She states that she cleans all of the doorknobs 5-10 times per day and that, despite her actions, the stress related to cleaning is becoming worse. What is this patient's diagnosis?", "answer": "Obsessive compulsive disorder (OCD)", "options": {"A": "Obsessive compulsive disorder (OCD)", "B": "Tic disorder", "C": "Panic Disorder (PD)", "D": "Generalized anxiety disorder (GAD)", "E": "Obsessive compulsive personality disorder (OCPD)"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old woman presents to the emergency department with a chief concern of shortness of breath. She was hiking when she suddenly felt unable to breathe and had to take slow deep breaths to improve her symptoms. The patient is a Swedish foreign exchange student and does not speak any English. Her past medical history and current medications are unknown. Her temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 120/min, respirations are 22/min, and oxygen saturation is 90% on room air. Physical exam is notable for poor air movement bilaterally and tachycardia. The patient is started on treatment. Which of the following best describes this patient's underlying pathology?\n\nFEV1 = Forced expiratory volume in 1 second\nFVC = Forced vital capacity\nDLCO = Diffusing capacity of carbon monoxide", "answer": "Normal DLCO", "options": {"A": "Decreased airway tone", "B": "Increased FEV1", "C": "Increased FEV1/FVC", "D": "Increased FVC", "E": "Normal DLCO"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A mother brings her 1-week-old son to the pediatrician because she is concerned about the child’s umbilicus. She notes that there appears to be fluid draining from the child’s umbilicus several times a day. The child has been breastfeeding normally. On exam, a small amount of clear light yellow fluid drains from the child’s umbilical stump when pressure is applied to the child’s lower abdomen. No bilious or feculent drainage is noted. Which of the following embryologic structures is associated with this patient’s condition?", "answer": "Urachus", "options": {"A": "Omphalomesenteric duct", "B": "Umbilical vein", "C": "Paramesonephric duct", "D": "Urachus", "E": "Ductus venosus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old woman, gravida 1, para 0, at 32 weeks' gestation is admitted to the hospital for the management of elevated blood pressures. On admission, her pulse is 81/min, and blood pressure is 165/89 mm Hg. Treatment with an intravenous drug is initiated. Two days after admission, she has a headache and palpitations. Her pulse is 116/min and regular, and blood pressure is 124/80 mm Hg. Physical examination shows pitting edema of both lower extremities that was not present on admission. This patient most likely was given a drug that predominantly acts by which of the following mechanisms?", "answer": "Direct dilation of the arterioles", "options": {"A": "Inhibition of β1, β2, and α1 receptors", "B": "Activation of α2 adrenergic receptors", "C": "Inhibition of angiotensin II production", "D": "Inhibition of sodium reabsorption", "E": "Direct dilation of the arterioles"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old G3P2002 presents to her obstetrician’s office for her first prenatal visit at ten weeks and two days gestation. She notes that she has felt nauseous the last several mornings and has been especially tired for a few weeks. Otherwise, she feels well. The patient has had two uncomplicated spontaneous vaginal deliveries at full term with her last child born six years ago. She is concerned about the risk of Down syndrome in this fetus, as her sister gave birth to an affected child at age 43. The patient has a history of generalized anxiety disorder, atopic dermatitis, and she is currently on escitalopram. At this visit, this patient’s temperature is 98.6°F (37.0°C), pulse is 70/min, blood pressure is 121/67 mmHg, and respirations are 13/min. The patient appears anxious, but overall comfortable, and cardiopulmonary and abdominal exams are unremarkable. Pelvic exam reveals normal female external genitalia, a closed and slightly soft cervix, a ten-week-sized uterus, and no adnexal masses. Which of the following is the best next step for definitively determining whether this patient’s fetus has Down syndrome?", "answer": "Chorionic villus sampling", "options": {"A": "Amniocentesis", "B": "Chorionic villus sampling", "C": "Anatomy ultrasound", "D": "Genetic testing of patient’s sister", "E": "Nuchal translucency test"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 48-year-old woman is transferred from her primary care physician's office to the emergency department for further evaluation of hypokalemia to 2.5 mEq/L. She was recently diagnosed with hypertension 2 weeks ago and started on medical therapy. The patient said that she enjoys all kinds of food and exercises regularly, but has not been able to complete her workouts as she usually does. Her temperature is 97.7°F (36.5°C), blood pressure is 107/74 mmHg, pulse is 80/min, respirations are 15/min, and SpO2 is 94% on room air. Her physical exam is unremarkable. Peripheral intravenous (IV) access is obtained. Her basic metabolic panel is obtained below.\n\nSerum:\nNa+: 135 mEq/L\nCl-: 89 mEq/L\nK+: 2.2 mEq/L\nHCO3-: 33 mEq/L\nBUN: 44 mg/dL\nGlucose: 147 mg/dL\nCreatinine: 2.3 mg/dL\nMagnesium: 2.0 mEq/L\n\nWhat is the next best step in management?", "answer": "Administer isotonic saline 1 liter via peripheral IV", "options": {"A": "Obtain an electrocardiogram", "B": "Administer potassium bicarbonate 50mEq per oral", "C": "Administer potassium chloride 40mEq via peripheral IV", "D": "Administer isotonic saline 1 liter via peripheral IV", "E": "Obtain urine sodium and creatinine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Nine days after being treated for a perforated gastric ulcer and sepsis, a 78-year-old woman develops decreased urinary output and malaise. She required emergency laparotomy and was subsequently treated in the intensive care unit for sepsis. Blood cultures grew Pseudomonas aeruginosa. The patient was treated with ceftazidime and gentamicin. She has type 2 diabetes mellitus, arterial hypertension, and osteoarthritis of the hips. Prior to admission, her medications were insulin, ramipril, and ibuprofen. Her temperature is 37.3°C (99.1°F), pulse is 80/min, and blood pressure is 115/75 mm Hg. Examination shows a healing surgical incision in the upper abdomen. Laboratory studies show:\nHemoglobin count 14 g/dL\nLeukocyte count 16,400 mm3\nSegmented neutrophils 60%\nEosinophils 2%\nLymphocytes 30%\nMonocytes 6%\nPlatelet count 260,000 mm3\nSerum\nNa+ 137 mEq/L\nCl- 102 mEq/L\nK+ 5.1 mEq/L\nUrea nitrogen 25 mg/dL\nCreatinine 4.2 mg/dL\nFractional excretion of sodium is 2.1%. Which of the following findings on urinalysis is most likely associated with this patient's condition?\"", "answer": "Muddy brown casts", "options": {"A": "WBC casts", "B": "Pigmented casts", "C": "Muddy brown casts", "D": "RBC casts", "E": "Waxy casts"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 50-year-old woman comes to the physician because of palpitations and irritability. Over the past 4 months, she has had several episodes of heart racing and skipping beats that lasted between 30 seconds and several hours. She has also been arguing with her husband more, often about the temperature being too warm. The patient has also lost 8.8-kg (19.4-lb) over the past 4 months, despite being less strict with her diet. She has mild asthma treated with inhaled bronchodilators. Her pulse is 102/min and blood pressure is 148/98 mm Hg. On physical examination, the skin is warm and moist. A mass is palpated in the anterior neck area. On laboratory studies, thyroid stimulating hormone is undetectable and there are antibodies against the thyrotropin-receptor. Thyroid scintigraphy shows diffusely increased iodine uptake. Two weeks later, a single oral dose of radioactive iodine is administered. This patient will most likely require which of the following in the long-term?", "answer": "L-thyroxine therapy", "options": {"A": "Near-total thyroidectomy", "B": "Estrogen replacement therapy", "C": "Methimazole therapy", "D": "Propranolol therapy", "E": "L-thyroxine therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old woman presents to the office with complaints of pain in her right breast for 5 days. The pain is moderate-to-intense and is localized to the upper quadrant of the right breast, and mainly to the areola for the past 48 hours. She adds that there is some nipple discharge on the same side and that the right breast is red. She was diagnosed with type 1 diabetes at the age of 10 years of age, for which she takes insulin. The family history is negative for breast and ovarian cancers, and endometrial disorders. She smokes one-half pack of cigarettes every day and binge drinks alcohol on the weekends. Two weeks ago she was hit by a volleyball while playing at the beach. There is no history of fractures or surgical procedures. The physical examination reveals a swollen, erythematous, and warm right breast with periareolar tenderness and nipple discharge. There are no palpable masses or lymphadenopathy. Which of the following is the most important risk factor for the development of this patient’s condition?", "answer": "Smoking", "options": {"A": "Age", "B": "Trauma", "C": "Smoking", "D": "Diabetes", "E": "Parity"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 33-year-old woman comes to the physician because of pain and sometimes numbness in her right thigh for the past 2 months. She reports that her symptoms are worse when walking or standing and are better while sitting. Three months ago, she started going to a fitness class a couple times a week. She is 163 cm (5 ft 4 in) tall and weighs 88 kg (194 lb); BMI is 33.1 kg/m2. Her vital signs are within normal limits. Examination of the skin shows no abnormalities. Sensation to light touch is decreased over the lateral aspect of the right anterior thigh. Muscle strength is normal. Tapping the right inguinal ligament leads to increased numbness of the affected thigh. The straight leg test is negative. Which of the following is the most appropriate next step in management of this patient?", "answer": "Advise patient to wear looser pants", "options": {"A": "MRI of the lumbar spine", "B": "Blood work for inflammatory markers", "C": "Advise patient to wear looser pants", "D": "X-ray of the hip", "E": "Reduction of physical activity"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old man presents to the office with progressive shortness of breath and cough. A chest X-ray shows prominent hilar lymph nodes and scattered nodular infiltrates. Biopsy of the latter reveals noncaseating granulomas. This patient most likely as a history of exposure to which of the following?", "answer": "Beryllium", "options": {"A": "Organic dust", "B": "Coal dust", "C": "Beryllium", "D": "Silica", "E": "Asbestos"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old man presents to the emergency department acutely confused. The patient's wife found him mumbling incoherently in the kitchen this morning as they were preparing for a hike. The patient was previously healthy and only had a history of mild forgetfulness, depression, asthma, and seasonal allergies. His temperature is 98.5°F (36.9°C), blood pressure is 122/62 mmHg, pulse is 119/min, and oxygen saturation is 98% on room air. The patient is answering questions inappropriately and seems confused. Physical exam is notable for warm, flushed, and dry skin. The patient's pupils are dilated. Which of the following is also likely to be found in this patient?", "answer": "Urinary retention", "options": {"A": "Coronary artery vasospasm", "B": "Hypoventilation", "C": "Increased bronchial secretions", "D": "QRS widening", "E": "Urinary retention"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old male presents to your office with fever and dyspnea on exertion. He has been suffering from chronic, non-productive cough for 1 year. You note late inspiratory crackles on auscultation. Pulmonary function tests reveal an FEV1/FVC ratio of 90% and an FVC that is 50% of the predicted value. Which of the following would you most likely see on a biopsy of this patient's lung?", "answer": "Subpleural cystic enlargement", "options": {"A": "Subpleural cystic enlargement", "B": "Charcot-Leyden crystals", "C": "Hyaline membranes", "D": "Arteriovenous malformations", "E": "Anti-GBM antibodies"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A team of intensivists working in a private intensive care unit (ICU) observe that the clinical efficacy of vancomycin is low, and proven nosocomial infections have increased progressively over the past year. A clinical microbiologist is invited to conduct a bacteriological audit of the ICU. He analyzes the microbiological reports of all patients treated with vancomycin over the last 2 years and takes relevant samples from the ICU for culture and antibiotic sensitivity analysis. The audit concludes that there is an increased incidence of vancomycin-resistant Enterococcus fecalis infections. Which of the following mechanisms best explains the changes that took place in the bacteria?", "answer": "Replacement of the terminal D-ala in the cell wall peptidoglycan by D-lactate", "options": {"A": "Protection of the antibiotic-binding site by Qnr protein", "B": "Replacement of the terminal D-ala in the cell wall peptidoglycan by D-lactate", "C": "Increased expression of efflux pumps which extrude the antibiotic from the bacterial cell", "D": "Decreased number of porins in the bacterial cell wall leading to decreased intracellular entry of the antibiotic", "E": "Production of an enzyme that hydrolyzes the antibiotic"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old male with a history of recurrent deep venous thromboses on warfarin presents to his hematologist for a follow-up visit. He reports that he feels well and has no complaints. His INR at his last visit was 2.5 while his current INR is 4.0. His past medical history is also notable for recent diagnoses of hypertension, hyperlipidemia, and gastroesophageal reflux disease. He also has severe seasonal allergies. He reports that since his last visit, he started multiple new medications at the recommendation of his primary care physician. Which of the following medications was this patient likely started on?", "answer": "Omeprazole", "options": {"A": "Omeprazole", "B": "Lisinopril", "C": "Hydrochlorothiazide", "D": "Atorvastatin", "E": "Cetirizine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old man presents to his physician with increased thirst and polyuria for the past 4 months. Patient also notes a decrease in his vision for the past 6 months and tingling in his feet. The medical history is significant for a chronic pyelonephritis and stage 2 chronic kidney disease. The current medications include losartan and atorvastatin. He reports a daily alcohol intake of 3 glasses of whiskey. The blood pressure is 140/90 mm Hg and the heart rate is 63/min. The BMI is 35.4 kg/m2. On physical examination, there is 2+ pitting edema of the lower legs and face. The pulmonary, cardiac, and abdominal examinations are within normal limits. There is no costovertebral angle tenderness noted. Ophthalmoscopy shows numerous microaneurysms and retinal hemorrhages concentrated in the fundus. The neurological examination reveals a symmetric decrease in vibration and 2 point discrimination in the patient’s feet and legs extending up to the lower third of the calves. The ankle-deep tendon reflexes are decreased bilaterally. The laboratory test results are as follows:\nSerum glucose (fasting) 140 mg/dL\nHbA1c 8.5%\nBUN 27 mg/dL\nSerum creatinine 1.3 mg/dL\neGFR 55 mL/min\nThe patient is prescribed the first-line drug recommended for his condition. Which of the following side effect is associated with this drug?", "answer": "Lactic acidosis", "options": {"A": "Iron deficiency anemia", "B": "Hypoglycemia", "C": "Lactic acidosis", "D": "Infections", "E": "Hyperkalemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 59-year-old man comes to the physician for evaluation of a progressively enlarging, 8-mm skin lesion on the right shoulder that developed 1 month ago. The patient has a light-skinned complexion and has had several dysplastic nevi removed in the past. A photograph of the lesion is shown. The lesion is most likely derived from cells that are also the embryological origin of which of the following tumors?", "answer": "Neuroblastoma", "options": {"A": "Neuroblastoma", "B": "Liposarcoma", "C": "Medullary thyroid cancer", "D": "Adrenal adenoma", "E": "Basal cell carcinoma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old woman comes to the physician because of a 14-hour history of left flank pain associated with dark urine. Her temperature is 37.2°C (99°F). The abdomen is soft with normal bowel sounds. There is guarding on the left lateral side and tenderness to palpation over the left costophrenic angle. An x-ray of the abdomen shows an 8-mm kidney stone. In addition to adequate hydration, which of the following diets should be advised for this patient?", "answer": "Low-protein diet", "options": {"A": "High-oxalate diet", "B": "Vitamin C supplementation", "C": "Low-protein diet", "D": "Low-calcium diet", "E": "High-sodium diet"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old woman presents to her primary care physician for recurrent deep venous thrombosis (DVT) of her left lower extremity. She is a vegetarian and often struggles to maintain an adequate intake of non-animal based protein. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and currently denies any illicit drug use, although she endorses a history of heroin use (injection). Her past medical history is significant for 4 prior admissions for lower extremity swelling and pain that resulted in diagnoses of deep venous thrombosis. Her vital signs include: temperature, 36.7°C (98.0°F); blood pressure, 126/74 mm Hg; heart rate, 87/min; and respiratory rate, 16/min. On physical examination, her pulses are bounding, the patent’s complexion is pale, breath sounds are clear, and heart sounds are normal. The spleen is mildly enlarged. She is admitted for DVT treatment and a full hypercoagulability workup. Which of the following is the best initial management for this patient?", "answer": "Begin heparin and warfarin", "options": {"A": "Begin heparin", "B": "Begin heparin and warfarin", "C": "Begin warfarin, target INR 2.0–3.0", "D": "Begin warfarin, target INR 2.5–3.5", "E": "Consult IR for IVC filter placement"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-year-old woman presents to the clinic, with her mother, complaining of a circular, itchy rash on her scalp for the past 3 weeks. Her mother is also worried about her hair loss. The girl has a past medical history significant for asthma. She needs to use her albuterol inhaler once per week on average. Her blood pressure is 112/70 mm Hg; the heart rate is 104/min; the respiratory rate is 20/min, and the temperature is 37.0°C (98.6°F). On exam, the patient is alert and interactive. Her lungs are clear on bilateral auscultation. On palpation, a tender posterior cervical node is present on the right side. Examination of the head is shown in the image. Which of the following is the best treatment option for the patient?", "answer": "Oral terbinafine", "options": {"A": "Subcutaneous triamcinolone", "B": "Ketoconazole shampoo", "C": "Oral doxycycline", "D": "Oral terbinafine", "E": "Topical betamethasone"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 66-year-old man is brought to the emergency department by his daughter because of 3 days of fever, chills, cough, and shortness of breath. The cough is productive of yellow sputum. His symptoms have not improved with rest and guaifenesin. His past medical history is significant for hypertension, for which he takes hydrochlorothiazide. He has a 30-pack-year history of smoking. His temperature is 38.9 C (102.0 F), blood pressure 88/56 mm Hg, and heart rate 105/min. Following resuscitation with normal saline, his blood pressure improves to 110/70 mm Hg. His arterial blood gas is as follows:\n\nBlood pH 7.52, PaO2 74 mm Hg, PaCO2 28 mm Hg, and HCO3- 21 mEq/L.\n\nWhich of the following acid-base disturbances best characterizes this patient's condition?", "answer": "Respiratory alkalosis", "options": {"A": "Normal acid-base status", "B": "Metabolic acidosis", "C": "Metabolic alkalosis", "D": "Respiratory acidosis", "E": "Respiratory alkalosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old patient presented to his family physician 8 years ago with initial complaints of increasing generalized stiffness with trouble initiating movement and worsening micrographia. He was started on levodopa after further evaluation led to a suspected diagnosis of Parkinson's disease; however, this therapy ultimately failed to improve the patient's symptoms. Additionally, over the ensuing 8 years since his initial presentation, the patient also developed symptoms including worsening balance, orthostatic hypotension, urinary incontinence, and impotence. The patient's overall condition deteriorated ever since this initial diagnosis with increasing disability from his motor symptoms, and he recently passed away at the age of 67, 8 years after his first presentation to his physician. The family requests an autopsy. Which of the following would be expected on autopsy evaluation of this patient's brain tissue?", "answer": "Glial cytoplasmic inclusions", "options": {"A": "Astrocytosis and caudate atrophy", "B": "Glial cytoplasmic inclusions", "C": "Round intracellular tau protein aggregates", "D": "Beta-amyloid plaques", "E": "Periventricular white matter plaques"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A newborn girl is delivered vaginally at term to a healthy 25-year-old G1P1. The pregnancy was uncomplicated. On examination, she was found to have a slight anal invagination, but no opening. Further examination shows a vestibular fistula and normally developed external genitalia. Which of the following statements about this condition is correct?", "answer": "There is a failure of the invagination and rupture of the dorsal portion of the cloacal membrane.", "options": {"A": "Such abnormal anatomy is formed after week 12 of intrauterine development.", "B": "The presence of an associated perineal or vestibular fistula is more likely in females with trisomy 21.", "C": "There is a failure of the division of the embryonic cloaca into the urogenital sinus and rectoanal canal.", "D": "There is a failure of the invagination and rupture of the dorsal portion of the cloacal membrane.", "E": "Other congenital abnormalities are extremely rare in patients with this condition."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 71-year-old man comes to the physician because of decreased sexual performance for the past 2 years. He reports that it takes longer for his penis to become erect, and he cannot maintain an erection for as long as before. His ejaculations have become less forceful. Once he has achieved an orgasm, he requires several hours before he can have another orgasm. He has been happily married for 40 years and he has no marital conflicts. His only medication is esomeprazole for gastroesophageal reflux disease. Examination shows coarse dark pubic and axillary hair. The skin of his lower extremity is warm to the touch; pedal pulses and sensation are intact. Rectal examination shows a symmetrically enlarged prostate with no masses. His fasting serum glucose is 96 mg/dL and his prostate-specific antigen is 3.9 ng/mL (N < 4). Which of the following etiologies is the most likely cause of the patient's symptoms?", "answer": "Physiologic", "options": {"A": "Vascular", "B": "Psychogenic", "C": "Neoplastic", "D": "Neurogenic", "E": "Physiologic"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old man comes to the otolaryngologist for the evaluation of a 6-month history of difficulty breathing through his nose and clear nasal discharge. He has a history of seasonal atopic rhinosinusitis. Anterior rhinoscopy shows a nasal polyp obstructing the superior nasal meatus. A CT scan of the head is most likely to show opacification of which of the following structures?", "answer": "Sphenoidal sinus and posterior ethmoidal sinuses", "options": {"A": "Pterygopalatine fossa and middle ethmoidal sinus", "B": "Maxillary sinus and anterior ethmoidal sinus", "C": "Sphenoidal sinus and posterior ethmoidal sinuses", "D": "Nasolacrimal duct and eustachian tube", "E": "Frontal sinus and anterior ethmoidal sinus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old man presents to a physician with repeated episodes of syncope and dizziness over the last month. On physical examination, his pulse is 64/min while all other vital signs are normal. His 24-hour ECG monitoring suggests a diagnosis of sinus node dysfunction. His detailed genetic evaluation shows that he carries a copy of a mutated gene “X” that codes for an ion channel, which is the most important ion channel underlying the automaticity of the sinoatrial node. This is the first ion channel to be activated immediately after hyperpolarization. Which of the following ion channels does the gene “X” code for?", "answer": "HCN-channels", "options": {"A": "HCN-channels", "B": "L-type voltage-dependent calcium channels", "C": "T-type voltage-dependent calcium channels", "D": "Fast delayed rectifier (IKr) voltage-dependent K+ channels", "E": "Stretch-activated cationic channels"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old man presents the office for a 3-day history of fever and fatigue. Upon further questioning, he says that he also had constant muscular pain, headaches, and fever during these days. He adds additional information by giving a history of regular unprotected sexual relationship with multiple partners. He is a non-smoker and drinks alcohol occasionally. The heart rate is 102/min, respiratory rate is 18/min, temperature is 38.0°C (100.4°F), and blood pressure is 120/80 mm Hg. On physical examination, he is icteric and hepatosplenomegaly is evident with diffuse muscular and abdominal tenderness particularly in the right upper quadrant. The serologic markers show the following pattern:\nAnti-HAV IgM negative\nHBsAg positive\nAnti-HBs negative\nIgM anti-HBc positive\nAnti-HCV negative\nAnti-HDV negative\nWhat is the most likely diagnosis?", "answer": "Viral hepatitis B", "options": {"A": "Viral hepatitis D", "B": "Viral hepatitis A", "C": "Viral hepatitis E", "D": "Viral hepatitis C", "E": "Viral hepatitis B"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "After a year of trying to conceive, a young couple in their early twenties decided to try in vitro fertilization. During preliminary testing of fertility, it was found that the male partner had dysfunctional sperm. Past medical history revealed that he had frequent sinus and lung infections throughout his life. The physician noted an abnormal exam finding on palpation of the right fifth intercostal space at the midclavicular line. What would be the most likely diagnosis responsible for this patient's infertility?", "answer": "Kartagener syndrome", "options": {"A": "Chédiak-Higashi syndrome", "B": "Williams syndrome", "C": "Cystic fibrosis", "D": "Adenosine deaminase deficiency", "E": "Kartagener syndrome"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old man presents to the office because of painless rectal bleeding for the past 3 months. He describes intermittent streaks of bright red blood on the toilet paper after wiping and blood on but not mixed within the stool. Occasionally, he has noted a small volume of blood within the toilet bowl, and he associates this with straining. For the past 2 weeks, he has noticed an 'uncomfortable lump' in his anus when defecating, which goes away by itself immediately afterwards. He says he has no abdominal pain, weight loss, or fevers. He is a well-appearing man that is slightly obese. Digital rectal examination shows bright red blood on the examination glove following the procedure. Anoscopy shows enlarged blood vessels above the pectinate line. Which of the following is the most likely cause?", "answer": "Grade 2 internal hemorrhoids", "options": {"A": "Grade 1 external hemorrhoids", "B": "Grade 1 internal hemorrhoids", "C": "Grade 2 external hemorrhoids", "D": "Grade 2 internal hemorrhoids", "E": "Grade 3 external hemorrhoids"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2755-g (6-lb 1-oz) baby boy is delivered at 37 weeks' gestation to a 29-year-old woman who is gravida 3, para 3. His mother received no prenatal care during her pregnancy. 12 hours after birth, he is evaluated for jaundice and lethargy. Laboratory studies show a hemoglobin concentration of 9.6 g/dL and a serum total bilirubin concentration of 10 mg/dL. The results of a direct Coombs test are positive. Further evaluation is most likely to show which of the following?", "answer": "Hepatosplenomegaly", "options": {"A": "Hyposthenuria", "B": "Positive eosin-5-maleimide binding test", "C": "Petechial rash", "D": "Hepatosplenomegaly", "E": "Elevated urinary coproporphyrins"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman presents to her primary care provider complaining of daytime drowsiness and fatigue. She reports that she can manage at most a couple of hours of work before needing a nap. She has also noted impaired memory and a 6.8 kg (15 lb) weight gain. She denies shortness of breath, chest pain, lightheadedness, or blood in her stool. At the doctor’s office, the vital signs include: pulse 58/min, blood pressure 104/68 mm Hg, and oxygen saturation 99% on room air. The physical exam is notable only for slightly dry skin. The complete blood count (CBC) is within normal limits. Which of the following is a likely additional finding in this patient?", "answer": "Hypercholesterolemia", "options": {"A": "Anxiety", "B": "Hypercholesterolemia", "C": "Lid lag", "D": "Palpitations", "E": "Tremor"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 5-month-old male infant is brought to the physician by his mother because of a generalized pruritic rash for 2-weeks. The itchiness often causes the infant to wake up at night. He was strictly breastfed until 4 months of age, when he was transitioned to formula feeding. His father has a history of asthma. His immunizations are up-to-date. He is at the 75th percentile for length and the 70th percentile for weight. Examination shows dry and scaly patches on the face and extensor surfaces of the extremities. The groin is spared. Which of the following is the most appropriate next step in management?", "answer": "Topical emollient\n\"", "options": {"A": "Topical coal tar", "B": "Oral acyclovir", "C": "Oral vitamin A", "D": "Tar-containing shampoo", "E": "Topical emollient\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 74-year-old man is rushed to the emergency department with left-sided weakness, facial deviation, and slurred speech. His wife first noticed these changes about an hour ago. The patient is having difficulty communicating. He can answer questions by nodding his head, and his wife is providing detailed information. He denies fever, loss of consciousness, head injury, bleeding, or seizures. Past medical history is significant for diabetes mellitus, hypertension, hyperlipidemia, ischemic heart disease, chronic kidney disease, and osteoarthritis. He had a heart attack 6 weeks ago. Baseline creatinine is 2.5 mg/dL, and he is not on hemodialysis. Medications include aspirin, clopidogrel, metoprolol, ramipril, rosuvastatin, and insulin detemir. Blood pressure is 175/95 mm Hg and the heart rate is 121/min. Muscle strength is decreased in both the upper and lower extremities on the left-side. A forehead sparing left sided facial weakness is also appreciated. An ECG reveals atrial fibrillation. An urgent head CT shows a hypodense area in the right parietal cortex with no indication of hemorrhage. Treatment with tissue plasminogen activator (tPA) is deferred due to which condition?", "answer": "History of myocardial infarction 6 weeks ago", "options": {"A": "Aspirin and clopidogrel use", "B": "Atrial fibrillation on electrocardiogram", "C": "Chronic kidney disease", "D": "History of myocardial infarction 6 weeks ago", "E": "Raised blood pressures"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 59-year-old woman is brought to the emergency room after collapsing at home. She had been sitting on her couch reading, when she started feeling lightheaded and lost consciousness. According to her husband, she was unconscious for approximately 30 seconds. Since regaining consciousness, she has continued to be lightheaded and dizzy. She has not had palpitations. Her only medication is simvastatin for hyperlipidemia. Her pulse is 37/min, respirations are 18/min, and blood pressure is 92/50 mm Hg. Her ECG is shown. Which of the following is the most appropriate next step in management?", "answer": "Administration of atropine", "options": {"A": "Administration of dopamine", "B": "Administration of atropine", "C": "Administration of norepinephrine", "D": "Administration of epinephrine", "E": "Transcutaneous pacemaker placement"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 78-year-old man presents to the hospital because of shortness of breath and chest pain that started a few hours ago. 3 weeks ago he had surgery for a total hip replacement with a prosthesis. The patient was treated with prophylactic doses of low-weight heparin until he was discharged. He did not have a fever, expectoration, or any accompanying symptoms. He has a history of right leg deep vein thrombosis that occurred 5 years ago. His vital signs include: heart rate 110/min, respiratory rate 22/min, and blood pressure 150/90 mm Hg. There were no significant findings on the physical exam. Chest radiography was within normal limits. What is the most likely diagnosis?", "answer": "Pulmonary thromboembolism", "options": {"A": "Pneumothorax", "B": "Pneumonia", "C": "Myocardial infarction", "D": "Pulmonary thromboembolism", "E": "Exacerbation of chronic lung disease"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 41-year-old woman with a past medical history significant for asthma and seasonal allergies presents with a new rash. She has no significant past surgical, social, or family history. The patient's blood pressure is 131/90 mm Hg, the pulse is 77/min, the respiratory rate is 17/min, and the temperature is 36.9°C (98.5°F). Physical examination reveals a sharply demarcated area of skin dryness and erythema encircling her left wrist. Review of systems is otherwise negative. Which of the following is the most likely diagnosis?", "answer": "Contact dermatitis", "options": {"A": "Tinea corporis", "B": "Scabies", "C": "Atopic dermatitis", "D": "Psoriasis", "E": "Contact dermatitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-year-old male is brought to the pediatrician for a check-up. The patient has a history of recurrent ear infections and several episodes of pneumonia. His mother reports the presence of scaly skin lesions on the face and in the antecubital and popliteal fossa since the patient was 2 months old. Physical examination also reveals bruising of the lower extremities and petechiae distributed evenly over the boy's entire body. A complete blood count reveals normal values except for a decreased platelet count of 45,000/mL. Which of the following findings would be expected on follow-up laboratory work-up of this patient's condition?", "answer": "Decreased CD43 expression on flow cytometry", "options": {"A": "Decreased CD18 expression on flow cytometry", "B": "Decreased CD43 expression on flow cytometry", "C": "Decreased CD8/CD4 ratio on flow cytometry", "D": "Increased IgM on quantitative immunoglobulin serology", "E": "Decreased IgE on quantitative immunoglobulin serology"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old woman makes an appointment with her primary care physician because she recently started experiencing post-menopausal bleeding. She states that she suffered from anorexia as a young adult and has been thin throughout her life. She says that this nutritional deficit is likely what caused her to not experience menarche until age 15. She used oral contraceptive pills for many years, has never been pregnant, and experienced menopause at age 50. A biopsy of tissue inside the uterus reveals foci of both benign and malignant squamous cells. Which of the following was a risk factor for the development of the most likely cause of her symptoms?", "answer": "Never becoming pregnant", "options": {"A": "Being underweight", "B": "Menarche at age 15", "C": "Menopause at age 50", "D": "Never becoming pregnant", "E": "Using oral contraceptive pills"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old woman is brought to the emergency department because of a 1-hour history of sudden-onset headache associated with nausea and vomiting. The patient reports she was sitting at her desk when the headache began. The headache is global and radiates to her neck. She has hypertension. She has smoked one pack of cigarettes daily for the last 10 years. She drinks alcohol occasionally. Her father had a stroke at the age 58 years. Current medications include hydrochlorothiazide. She is in severe distress. She is alert and oriented to person, place, and time. Her temperature is 38.2°C (100.8°F), pulse is 89/min, respirations are 19/min, and blood pressure is 150/90 mm Hg. Cardiopulmonary examination shows no abnormalities. Cranial nerves II–XII are intact. She has no focal motor or sensory deficits. She flexes her hips and knees when her neck is flexed while lying in a supine position. A CT scan of the head is shown. Which of the following is the most appropriate intervention?", "answer": "Perform surgical clipping", "options": {"A": "Administer intravenous vancomycin and ceftriaxone", "B": "Administer intravenous alteplase", "C": "Perform burr hole surgery", "D": "Perform decompressive craniectomy", "E": "Perform surgical clipping"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old nulligravid woman comes to the physician because of a 10-day history of small quantities of intermittent, blood-tinged discharge from her left nipple. There is no personal or family history of serious illness. She has smoked 1 pack of cigarettes daily for 5 years. Her last menstrual period was 12 days ago. She is sexually active and uses condoms inconsistently. Physical examination shows scant serosanguinous fluid expressible from the left nipple. There is no palpable breast mass or axillary lymphadenopathy. Examination shows no other abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Subareolar ultrasound", "options": {"A": "Subareolar ultrasound", "B": "Image-guided core biopsy of the affected duct", "C": "Nipple discharge cytology", "D": "Breast MRI", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator is studying the immune response and the spleen in a mouse model infected with Escherichia coli. Which of the following anatomical sites in the spleen is important for the initial maturation of B cells that will ultimately target Escherichia coli?", "answer": "Germinal center", "options": {"A": "Periarteriolar lymphatic sheaths", "B": "Red pulp", "C": "Marginal zone", "D": "Germinal center", "E": "Sinusoids"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old woman at 30 weeks gestation is rushed to the emergency room with the sudden onset of vaginal bleeding accompanied by intense abdominopelvic pain and uterine contractions. The intensity and frequency of pain have increased in the past 2 hours. This is her 1st pregnancy and she was diagnosed with gestational diabetes several weeks ago. Her vital signs include a blood pressure of 124/68 mm Hg, a pulse of 77/min, a respiratory rate of 22/min, and a temperature of 37.0°C (98.6°F). The abdominal examination is positive for a firm and tender uterus. An immediate cardiotocographic evaluation reveals a fetal heart rate of 150/min with prolonged and repetitive decelerations and high-frequency and low-amplitude uterine contractions. Your attending physician warns you about delaying the vaginal physical examination until a quick sonographic evaluation is completed. Which of the following is the most likely diagnosis in this patient?", "answer": "Placenta abruption", "options": {"A": "Miscarriage", "B": "Vasa previa", "C": "Uterine rupture", "D": "Placenta previa", "E": "Placenta abruption"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 18-month-old girl is brought to the emergency room by her mother because of wheezing for 1 day. The baby has never had similar symptoms. She also has a runny nose and a cough. She is not feeding well. Her immunizations are up-to-date. Her rectal temperature is 38.8°C (101.8°F), the heart rate is 120/min, and the respiratory rate is 23/min. On examination, a clear nasal discharge is noticed with intercostal retractions. Chest auscultation reveals bilateral fine rales and diffuse fine wheezing. A chest X-ray is given in the exhibit. What is the most likely diagnosis?\n ", "answer": "Bronchiolitis", "options": {"A": "Bronchial asthma", "B": "Bronchiolitis", "C": "Bacterial pneumonia", "D": "Bronchial foreign body", "E": "Croup"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old man presents to the urgent care clinic complaining of cough and unintentional weight loss over the past 3 months. He works as a computer engineer, and he informs you that he has been having to meet several deadlines recently and has been under significant stress. His medical history is significant for gout, hypertension, hypercholesterolemia, diabetes mellitus type 2, and pulmonary histoplasmosis 10 years ago. He currently smokes 2 packs of cigarettes/day, drinks a 6-pack of beer/day, and he endorses a past history of cocaine use back in the early 2000s but currently denies any drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 18/min. His physical examination shows minimal bibasilar rales, but otherwise clear lungs on auscultation, grade 2/6 holosystolic murmur, and a benign abdominal physical examination. However, on routine lab testing, you notice that his sodium is 127 mEq/L. His chest X-ray is shown in the picture. Which of the following is the most likely underlying diagnosis?", "answer": "Small cell lung cancer", "options": {"A": "Small cell lung cancer", "B": "Non-small cell lung cancer", "C": "Large cell lung cancer", "D": "Squamous cell carcinoma", "E": "Adenocarcinoma"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old female presents to an urgent care clinic for evaluation of a loose bowel movement that she developed after returning from her honeymoon in Mexico last week. She states that she has been having watery stools for the past 3 days at least 3 times per day. She now has abdominal cramps as well. She has no significant past medical history, and the only medication she takes is depot-medroxyprogesterone acetate. Her blood pressure is 104/72 mm Hg; heart rate is 104/min; respiration rate is 14/min, and temperature is 39.4°C (103.0°F). Her physical examination is normal aside from mild diffuse abdominal tenderness and dry mucous membranes. Stool examination reveals no ova. Fecal leukocytes are not present. A stool culture is pending. In addition to oral rehydration, which of the following is the best treatment option for this patient?", "answer": "Ciprofloxacin", "options": {"A": "Ciprofloxacin", "B": "Trimethoprim-sulfamethoxazole", "C": "Metronidazole", "D": "Doxycycline", "E": "Albendazole"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 12-year-old girl is brought to a pediatrician by her parents to establish care after moving to a new state. She does not have any complaints. Her past medical history is insignificant, and immunization history is up to date. The physical examination reveals a slightly raised strawberry-colored nodule on the skin of her abdomen below the umbilicus, as seen in the image. She adds that the nodule has been present ever since she can remember and has not changed in color or size. Which of the following neoplasms is associated with this patient's skin lesion?", "answer": "Hemangioma", "options": {"A": "Hemangioma", "B": "Sarcoma", "C": "Carcinoma", "D": "Lymphoma", "E": "Malignant melanoma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man comes to the physician because of progressive abdominal distension and swelling of his legs for 4 months. He has a history of ulcerative colitis. Physical examination shows jaundice. Abdominal examination shows shifting dullness and dilated veins in the periumbilical region. This patient's abdominal findings are most likely caused by increased blood flow in which of the following vessels?", "answer": "Superior epigastric vein", "options": {"A": "Left gastric vein", "B": "Hepatic vein", "C": "Superior epigastric vein", "D": "Superior mesenteric vein", "E": "Superior rectal vein"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old man comes to the physician for the evaluation of a severely pruritic skin rash. Physical examination shows a symmetrical rash over the knees and elbows with tense, grouped vesicles, and several excoriation marks. Microabscesses in the papillary dermis are seen on light microscopy. Immunofluorescence shows deposits of immunoglobulin A at the tips of dermal papillae. This patient's skin findings are most likely associated with which of the following?", "answer": "Gliadin-dependent hypersensitivity", "options": {"A": "Mite eggs and fecal pellets", "B": "Gliadin-dependent hypersensitivity", "C": "Multinucleated giant cells", "D": "Nail pitting", "E": "Positive Nikolsky sign"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old man presents to the emergency department with agitation and combativeness. The paramedics who brought him in say that he was demonstrating violent, reckless behavior and was running into oncoming traffic. Chemical sedation is required to evaluate the patient. Physical examination reveals horizontal and vertical nystagmus, tachycardia, and profuse diaphoresis. Which of the following is the most likely causative agent in this patient?", "answer": "Phencyclidine (PCP)", "options": {"A": "Cannabis", "B": "Cocaine", "C": "Gamma-hydroxybutyric acid (GHB)", "D": "Lysergic acid diethylamide (LSD)", "E": "Phencyclidine (PCP)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "One day after undergoing a left carotid endarterectomy, a 63-year-old man has a severe headache. He describes it as 9 out of 10 in intensity. He has nausea. He had 80% stenosis in the left carotid artery and received heparin prior to the surgery. He has a history of 2 transient ischemic attacks, 2 and 4 months ago. He has hypertension, type 2 diabetes mellitus, and hypercholesterolemia. He has smoked one pack of cigarettes daily for 40 years. He drinks 1–2 beers on weekends. Current medications include lisinopril, metformin, sitagliptin, and aspirin. His temperature is 37.3°C (99.1°F), pulse is 111/min, and blood pressure is 180/110 mm Hg. He is confused and oriented only to person. Examination shows pupils that react sluggishly to light. There is a right facial droop. Muscle strength is decreased in the right upper and lower extremities. Deep tendon reflexes are 3+ on the right. There is a left cervical surgical incision that shows no erythema or discharge. Cardiac examination shows no abnormalities. A complete blood count and serum concentrations of creatinine, electrolytes, and glucose are within the reference range. A CT scan of the head is shown. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Hypertension", "options": {"A": "Degree of carotid stenosis", "B": "Aspirin therapy", "C": "Perioperative heparin", "D": "Hypertension", "E": "Smoking"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old mother presents to her primary care physician for wrist pain. The patient recently gave birth to a healthy newborn at 40 weeks gestation. Beginning one week ago, she started having pain over her wrist that has steadily worsened. The patient notes that she also recently fell while walking and broke the fall with her outstretched arm. The patient is an accountant who works from home and spends roughly eight hours a day typing or preparing financial statements. Recreationally, the patient is a competitive cyclist who began a rigorous training routine since the birth of her child. The patient's past medical history is notable for hypothyroidism that is treated with levothyroxine. On physical exam, inspection of the wrist reveals no visible or palpable abnormalities. Pain is reproduced when the thumb is held in flexion, and the wrist is deviated toward the ulna. The rest of the patient's physical exam is within normal limits. Which of the following is the best next step in management?", "answer": "Rest and ibuprofen", "options": {"A": "Radiography of the wrist", "B": "Thumb spica cast", "C": "Wrist guard to be worn during work and at night", "D": "Repositioning of the wrist while cycling", "E": "Rest and ibuprofen"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old woman comes to the physician because of a 2-week history of painful swelling on the right side of her face. The pain worsens when she eats. Examination of the face shows a right-sided, firm swelling that is tender to palpation. Oral examination shows no abnormalities. Ultrasonography shows a stone located in a duct that runs anterior to the masseter muscle and passes through the buccinator muscle. Sialoendoscopy is performed to remove the stone. At which of the following sites is the endoscope most likely to be inserted during the procedure?", "answer": "Lateral to the second upper molar tooth", "options": {"A": "Lateral to the superior labial frenulum", "B": "Lateral to the lingual frenulum", "C": "Lateral to the second upper molar tooth", "D": "Into the floor of the mouth", "E": "Into the mandibular foramen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Ten days after the vaginal delivery of a healthy infant girl, a 27-year-old woman is brought to the physician by her husband because of frequent mood changes. She has been tearful and anxious since she went home from the hospital 2 days after delivery. She says that she feels overwhelmed with her new responsibilities and has difficulties taking care of her newborn because she feels constantly tired. She only sleeps for 2 to 3 hours nightly because the baby “is keeping her awake.” Sometimes, the patient checks on her daughter because she thinks she heard her cry but finds her sleeping quietly. Her husband says that she is afraid that something could happen to the baby. She often gets angry at him and has yelled at him when he picks up the baby without using a hand sanitizer beforehand. She breastfeeds the baby without any problems. The patient's mother has bipolar disorder with psychotic features. The patient's vital signs are within normal limits. Physical examination shows an involuting uterus consistent in size with her postpartum date. Mental status examination shows a labile affect with no evidence of homicidal or suicidal ideation. Laboratory studies show a hemoglobin concentration of 13 g/dL and a thyroid-stimulating hormone level of 3.1 μU/mL. Which of the following is the most appropriate next step in management?", "answer": "Reassurance", "options": {"A": "Sertraline therapy", "B": "Cognitive behavioral therapy", "C": "Risperidone therapy", "D": "Reassurance", "E": "Bupropion therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 82-year-old man dies in a motor vehicle collision. At autopsy, the heart shows slight ventricular thickening. There are abnormal, insoluble aggregations of protein filaments in beta-pleated linear sheets in the ventricular walls and, to a lesser degree, in the atria and lungs. No other organs show this abnormality. Bone marrow examination shows no plasma cell dyscrasia. The abnormal protein aggregations are most likely composed of which of the following?", "answer": "Normal transthyretin", "options": {"A": "Natriuretic peptide", "B": "Normal transthyretin", "C": "Immunoglobulin light chain", "D": "Serum amyloid A", "E": "β-amyloid peptide\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the physician with complaints of gingival growth in the lower jaw with associated pain for the past few weeks. He has no history of trauma or any other significant medical conditions. His temperature is 37.0°C (98.6°F), pulse is 92/min, and respiratory rate is 24/min. On extraoral examination, a swelling of 4 cm x 2 cm is present on the left lower jaw. On intraoral examination, a diffuse erythematous swelling covered with necrotic slough is present on the gingiva. Computed tomography (CT) scan of the head shows multiple soft tissue density lesions involving mandibular, maxillary, left occipital, and temporal regions. Which of the following findings, if present, would be the most specific indicator of the disease in this patient?", "answer": "Birbeck granules", "options": {"A": "Ragged red fibers", "B": "Prominent perifascicular and paraseptal atrophy", "C": "Birbeck granules", "D": "Endomysial inflammatory infiltrates and myofiber necrosis", "E": "Polygonal myofibers with peripherally placed nuclei"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 62-year-old man presents to the emergency department with chest pain. He was at home watching television when he suddenly felt chest pain that traveled to his back. The patient has a past medical history of alcoholism, obesity, hypertension, diabetes, and depression. His temperature is 98.4°F (36.9°C), blood pressure is 177/118 mmHg, pulse is 123/min, respirations are 14/min, and oxygen saturation is 97% on room air. Physical exam reveals a S4 on cardiac exam and chest pain that seems to worsen with palpation. The patient smells of alcohol. The patient is started on 100% oxygen and morphine. Which of the following is the best next step in management?", "answer": "Labetalol", "options": {"A": "Aspirin", "B": "CT scan", "C": "Labetalol", "D": "Nitroprusside", "E": "NPO, IV fluids, serum lipase"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old G1P0 woman comes to the emergency department complaining that her water just broke. She reports irregular prenatal care due to her erratic schedule. She is also unsure of her gestational age but claims that her belly began to show shortly after she received her thyroidectomy for her Graves disease about 9 months ago. She denies any known fevers, chills, abnormal vaginal discharge/bleeding, or sexually transmitted infections. She develops frequent and regular contractions and subsequently goes into active labor. A fetus was later vaginally delivered with a fetal heart rate of 180 bpm. A neonatal physical examination demonstrates a lack of a sagittal cranial suture and an APGAR score of 8 and 8, at 1 and 5 minutes respectively. What findings would you expect in the baby?", "answer": "High levels of free T4 and total T3", "options": {"A": "Group B streptococcus in blood", "B": "High levels of free T4 and total T3", "C": "High thyroid-stimulating hormone", "D": "Low hemoglobin", "E": "Pericardial effusion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old male visits a urologist and reports that for the past 2 weeks, his penis has been gradually curving to the right with associated pain during intercourse. He is able to have a normal erection and he does not recollect of any trauma to his penis. Although he is married, he admits to having unprotected sexual relationship with several females in the past year. His vitals are normal and physical examination in unremarkable except for a lesionless curved penis. It is painless to touch. Test results for sexually transmitted disease is pending. Which of the following is the most likely cause?", "answer": "Fibrosis of tunica albuginea", "options": {"A": "Fibrosis of corpus cavernosa", "B": "Congenital hypospadias", "C": "Syphilitic chancre", "D": "Fibrosis of tunica albuginea", "E": "Hypertrophy of corpus cavernosa"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-day-old newborn has difficulty feeding and diarrhea for 2 days. During this period he has vomited after each of his feeds. He was born at 28 weeks' gestation and weighed 1100-g (2-lb 7-oz). His feeds consist of breast milk and cow milk based-formula. He appears lethargic. His temperature is 36.4°C (97.5°F), pulse is 120/min, respirations are 67/min and blood pressure is 70/35 mm Hg. Examination shows diffuse abdominal tenderness; rigidity and guarding are present. Bowel sounds are absent. Test of the stool for occult blood is positive. His hemoglobin concentration is 12.8 g/dL, leukocyte count is 18,000/mm3 and platelet count is 78,000/mm3. An x-ray of the abdomen is shown. Which of the following is the most likely diagnosis?", "answer": "Necrotizing enterocolitis\n\"", "options": {"A": "Meckel diverticululum", "B": "Intussusception", "C": "Hypertrophic pyloric stenosis", "D": "Duodenal atresia", "E": "Necrotizing enterocolitis\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-month-old male infant is brought to a pediatrician by his guardian for scheduled immunizations. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. The infant is generally healthy; however, the guardian is concerned about multiple patches of bluish discolorations on the skin overlying the lower back and sacrum. A review of medical records indicates that these patches have been present since birth. On further review the child was placed into protective services due to neglect and abuse by his biological family. On physical examination, his vital signs are normal. The pediatrician notes the presence of multiple blue-brown patches over the lumbosacral region, buttocks, and back. These patches are soft and nontender on palpation. Which of the following is the best next step in management of the infant?", "answer": "Reassurance", "options": {"A": "Reassurance", "B": "Topical hydrocortisone cream", "C": "Skin biopsy", "D": "Inform child protective services", "E": "Radiographic skeletal survey"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A previously healthy 46-year-old woman comes to the physician with a one-week history of productive cough and fatigue. Two weeks ago, she had fever, nasal congestion, rhinorrhea, and myalgias that resolved with supportive care. She has not traveled out of the United States. Pulmonary examination shows dullness to percussion and increased fremitus at the right middle lobe. An x-ray of the chest is shown. A sputum sample is most likely to show which of the following findings?", "answer": "Gram-positive, catalase-positive cocci", "options": {"A": "Gram-positive, catalase-positive cocci", "B": "Silver-staining, gram-negative bacilli", "C": "Gram-positive, beta-hemolytic cocci in chains", "D": "Septate, acute-branching hyphae", "E": "Encapsulated, gram-negative coccobacilli"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old man comes to the physician because of progressive swelling of the left lower leg for 4 months. One year ago, he had an episode of intermittent fever and tender lymphadenopathy that occurred shortly after he returned from a trip to India and resolved spontaneously. Physical examination shows 4+ nonpitting edema of the left lower leg. His leukocyte count is 8,000/mm3 with 25% eosinophils. A blood smear obtained at night confirms the diagnosis. Treatment with diethylcarbamazine is initiated. Which of the following is the most likely route of transmission of the causal pathogen?", "answer": "Deposition of thread-like larvae into the skin by a female mosquito", "options": {"A": "Deposition of larvae into the skin by a female black fly", "B": "Penetration of the skin by cercariae from contaminated fresh water", "C": "Deposition of thread-like larvae into the skin by a female mosquito", "D": "Penetration of the skin by hookworms in feces", "E": "Ingestion of encysted larvae in undercooked pork\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old woman presents with progressively worsening headache, photophobia, and intermittent fever that have lasted for 6 days. She says her headache is mostly frontal and radiates down her neck. She denies any recent history of blood transfusions, recent travel, or contact with animals. Her past medical history is unremarkable. She is sexually active with a single partner for the past 3 years. Her temperature is 38.5°C (101.3°F). On physical examination, she appears pale and diaphoretic. A fine erythematous rash is noted on the neck and forearms. A lumbar puncture is performed and CSF analysis reveals:\nOpening pressure: 300 mm H2O\n  Erythrocytes: None\nLeukocytes: 72/mm3\nNeutrophils: 10%\nLymphocytes: 75%\nMononuclear: 15%\nProtein: 100 mg/dL\nGlucose: 70 mg/dL\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Enterovirus meningitis", "options": {"A": "Brucellosis", "B": "Lymphocytic choriomeningitis virus", "C": "Mumps meningitis", "D": "Ehrlichiosis", "E": "Enterovirus meningitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man comes to the emergency room complaining of severe, episodic back pain. He states that it started suddenly this morning. The pain is 9/10 and radiates to his left groin. He endorses seeing blood in his urine earlier but denies dysuria or abnormal urethral discharge. His medical history is significant for Crohn disease, gout, and insulin-dependent diabetes. He takes insulin, allopurinol, and sulfasalazine. He is sexually active with multiple women and uses condoms inconsistently. He drinks 4 cans of beer on the weekends. He denies tobacco use or other recreational drug use. The patient’s temperature is 99°F (37.2°C), blood pressure is 121/73 mmHg, pulse is 89/min, and respirations are 14/min with an oxygen saturation of 94% on room air. A contrast computed tomography of the abdomen and pelvis reveals a 5-mm stone in the left ureter without evidence of hydronephrosis. Urinalysis and urine microscopy reveal hematuria and envelope-shaped crystals. Which of the following most likely contributed to the development of the patient’s acute symptoms?", "answer": "Crohn disease", "options": {"A": "Crohn disease", "B": "Diabetes mellitus", "C": "Gout", "D": "Medication effect", "E": "Sexual history"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 19-year-old man with a history of type 1 diabetes presents to the emergency department for the evaluation of a blood glucose level of 492 mg/dL. Laboratory examination revealed a serum bicarbonate level of 13 mEq/L, serum sodium level of 122 mEq/L, and ketonuria. Arterial blood gas demonstrated a pH of 6.9. He is admitted to the hospital and given bicarbonate and then started on an insulin drip and intravenous fluid. Seven hours later when his nurse is making rounds, he is confused and complaining of a severe headache. Repeat sodium levels are unchanged, although his glucose level has improved. His vital signs include a temperature of 36.6°C (98.0°F), pulse 50/min, respiratory rate 13/min and irregular, and blood pressure 177/95 mm Hg. What other examination findings would be expected in this patient?", "answer": "Papilledema", "options": {"A": "Pupillary constriction", "B": "Hypoglycemia", "C": "Pancreatitis", "D": "Papilledema", "E": "Peripheral edema"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old African American college student comes to the office for a scheduled visit. He has been healthy, although he reports occasional flank discomfort which comes and goes. He denies any fever, chills, dysuria, or polyuria in the past year. His vaccinations are up to date. His family history is unknown, as he was adopted. He smokes 1 pack of cigarettes every 3 days, drinks socially, and denies any current illicit drug use, although he endorses a history of injection drug use. He currently works as a waiter to afford his college tuition. His physical examination shows a young man with a lean build, normal heart sounds, clear breath sounds, bowel sounds within normal limits, and no lower extremity edema. You order a urinalysis which shows 8 red blood cells (RBCs) per high-power field (HPF). The test is repeated several weeks later and shows 6 RBCs/HPF. What is the most appropriate next step in management?", "answer": "Intravenous (IV) pyelogram", "options": {"A": "Plain abdominal X-ray", "B": "Intravenous (IV) pyelogram", "C": "24-hour urine collection test", "D": "Repeat urinalysis in 6 months", "E": "Observation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 11-year-old girl is brought to the emergency department after she fell during a dance class. She was unable to stand after the accident and has a painful and swollen knee. On presentation she says that she has had 2 previous swollen joints as well as profuse bleeding after minor cuts. Based on her presentation, a panel of bleeding tests is obtained with the following results:\n\nBleeding time: 11 minutes\nProthrombin time: 12 seconds\nPartial thromboplastin time: 52 seconds\n\nWhich of the following treatments would be most effective in treating this patient's condition?", "answer": "Desmopressin", "options": {"A": "Desmopressin", "B": "Factor VII repletion", "C": "Factor VIII repletion", "D": "Platelet infusion", "E": "Vitamin K"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Researchers are studying the effects of a new medication for the treatment of type 2 diabetes. A randomized group of 100 subjects is given the new medication 1st for 2 months, followed by a washout period of 2 weeks, and then administration of the gold standard medication for 2 months. Another randomized group of 100 subjects is be given the gold standard medication 1st for 2 months, followed by a washout period of 2 weeks, and then administration of the new medication for 2 months. What is the main disadvantage of this study design?", "answer": "Carryover effect", "options": {"A": "Increasing confounding bias", "B": "Increasing selection bias", "C": "Decreasing power", "D": "Hawthorne effect", "E": "Carryover effect"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old woman, gravida 1, para 0, at 26 weeks' gestation comes to the physician for a routine prenatal examination. Her pregnancy has been uneventful. Physical examination shows a uterus consistent in size with a 26-week gestation. She is given an oral 50-g glucose load; 1 hour later, her serum glucose concentration is 116 mg/dL. Which of the following most likely occurred immediately after the entrance of glucose into the patient's pancreatic beta-cells?", "answer": "Generation of adenosine triphosphate", "options": {"A": "Closure of membranous potassium channels", "B": "Generation of adenosine triphosphate", "C": "Increased expression of hexokinase I mRNA", "D": "Depolarization of beta-cell membrane", "E": "Exocytosis of insulin granules"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "You are treating a neonate with meningitis using ampicillin and a second antibiotic, X, that is known to cause ototoxicity. What is the mechanism of antibiotic X?", "answer": "It binds the 30s ribosomal subunit and inhibits formation of the initiation complex", "options": {"A": "It binds the 50S ribosomal subunit and inhibits peptidyltransferase", "B": "It binds the 50S ribosomal subunit and inhibits formation of the initiation complex", "C": "It binds the 30s ribosomal subunit and inhibits formation of the initiation complex", "D": "It binds the 30s ribosomal subunit and reversibly inhibits translocation", "E": "It binds the 50s ribosomal subunit and reversibly inhibits translocation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old man is brought to the emergency department after being found down on the sidewalk. On presentation, he is found to have overdosed on opioids so he is given naloxone and quickly recovers. Physical exam also reveals lumps on his neck and face that are covered by small yellow granules. These lumps are slowly draining yellow pus-like fluid. He says that these lumps have been present for several months, but he has ignored them because he has not had any fever or pain from the lumps. He does not recall the last time he visited a primary care physician or a dentist. Oral exam reveals multiple cavities and abscesses. The most likely cause of this patient's facial lumps has which of the following characteristics?", "answer": "Gram-positive rod", "options": {"A": "Acid-fast rods", "B": "Gram-negative cocci", "C": "Gram-negative rod", "D": "Gram-positive cocci", "E": "Gram-positive rod"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old woman presents to the physician because of fever and sore throat for 2 days. She also reports generalized body pain and fatigue over this period. She was diagnosed with Graves’ disease 6 months ago. Because of arthralgias and rash due to methimazole 3 months ago, her physician switched methimazole to PTU. She appears ill. The vital signs include: temperature 38.4℃ (101.1℉), pulse 88/min, respiratory rate 12/min, and blood pressure 120/80 mm Hg. A 1 × 1 cm ulcer is seen on the side of the tongue and is painful with surrounding erythema. Examination of the neck, lungs, heart, and abdomen shows no abnormalities. She had normal liver aminotransferases last week. Which of the following is the most important diagnostic study at this time?", "answer": "Complete blood count with differential", "options": {"A": "Alanine aminotransferase", "B": "Complete blood count with differential", "C": "Erythrocyte sedimentation rate", "D": "Thyroid-stimulating hormone", "E": "No further testing is indicated"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man with a history of poorly controlled human immunodeficiency virus (HIV) infection presents to the emergency room complaining of clumsiness and weakness. He reports a 3-month history of worsening balance, asymmetric muscle weakness, and speech difficulties. He recently returned from a trip to Guatemala to visit his family. He has been poorly compliant with his anti-retroviral therapy and his most recent CD4 count was 195. His history is also notable for rheumatoid arthritis and hepatitis C. His temperature is 99°F (37.2°C), blood pressure is 140/90 mmHg, pulse is 95/min, and respirations are 18/min. On exam, he has 4/5 strength in his right upper extremity, 5/5 strength in his left upper extremity, 5/5 strength in his right lower extremity, and 3/5 strength in his left lower extremity. His speech is disjointed with intermittent long pauses between words. Vision is 20/100 in the left eye and 20/40 in his right eye; previously, his eyesight was 20/30 bilaterally. This patient most likely has a condition caused by which of the following types of pathogens?", "answer": "Polyomavirus", "options": {"A": "Arenavirus", "B": "Bunyavirus", "C": "Herpesvirus", "D": "Picornavirus", "E": "Polyomavirus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-year-old girl is brought to the pediatrician by her father for an annual physical examination. The father reports that the patient is a happy and healthy child, but he sometimes worries about her weight. He says that she is a “picky” eater and only wants chicken nuggets and French fries. He also notes some mild acne on her cheeks and forehead but thinks it’s because she “doesn’t like baths.” The father says she has met all her pediatric milestones. She has recently started kindergarten, can tell time, and is beginning to read. Her teacher says she gets along with her classmates well. The patient was born at 38 weeks gestation. She has no chronic medical conditions and takes only a multivitamin. Height and weight are above the 95th percentile. Physical examination reveals scattered comedones on the patient’s forehead and bilateral cheeks. There is palpable breast tissue bilaterally with raised and enlarged areolae. Scant axillary hair and coarse pubic hair are also noted. A radiograph of the left hand shows a bone age of 9 years. Serum follicular stimulating hormone (FSH) level is 9.6 mU/mL (normal range 0.7-5.3 mU/mL) and luteinizing hormone (LH) level is 6.4 mU/mL (normal range < 0.26 mU/mL). Which of the following is the most appropriate diagnostic test?", "answer": "Head computed tomography (CT)", "options": {"A": "17-hydroxyprogesterone levels", "B": "Dehydroepiandrosterone sulfate levels", "C": "Estrogen levels", "D": "Head computed tomography (CT)", "E": "Pelvic ultrasound"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old woman presents complaining of pain in her hands. She reports that the pain is in both hands, and that it is usually worse in the morning. She reports that her hands are also stiff in the morning, but that this gradually improves throughout the morning. She notes, however, that her symptoms seem to be getting worse over the last three months. What is the most likely pathogenesis of her disease process?", "answer": "Production of antibodies against antibodies", "options": {"A": "Repetitive microtrauma", "B": "Type 1 hypersensitivity reaction", "C": "Production of antibodies against smooth muscle", "D": "Production of antibodies against antibodies", "E": "Anti-neutrophil cytoplasmic antibody production"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old male presents to the emergency department with sudden onset shortness of breath and epigastric pain. The patient has a past medical history of GERD, obesity, diabetes mellitus type II, anxiety, glaucoma, and irritable bowel syndrome. His current medications include omeprazole, insulin, metformin, lisinopril, and clonazepam as needed. The patient's temperature is 99.5°F (37.5°C), pulse is 112/min, blood pressure is 90/70 mmHg, respirations are 18/min, and oxygen saturation is 95% on room air. On physical exam the patient's lungs are clear to auscultation bilaterally. JVD is notable and cardiac auscultation is not revealing. An EKG is obtained in the emergency department. The patient is given a bolus of fluids and his pulse becomes 80/min with a blood pressure of 105/75 mmHg. The patient is then started on beta-blockers, oxygen, nitroglycerin, morphine, IV fluids, and aspirin. Repeat vitals demonstrate a blood pressure of 80/65 mmHg. Which of the following is the best explanation of this patient's current vital signs?", "answer": "Increased cGMP", "options": {"A": "Beta-adrenergic blockade", "B": "Increased cGMP", "C": "Fluid overload", "D": "Ventricular free wall rupture", "E": "Left ventricular failure"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 70-year-old man comes to the physician because of a painless skin lesion on his neck for the past 5 months. The lesion has gradually become darker in color and is often pruritic. He has a similar lesion on the back. He is a retired landscaper. He has smoked half a pack of cigarettes daily for 45 years. Physical examination shows a 0.9-cm hyperpigmented papule on the neck with a greasy, wax-like, and stuck-on appearance. Histopathologic examination is most likely to show which of the following?", "answer": "Immature keratinocytes with small keratin-filled cysts", "options": {"A": "S100-positive epithelioid cells with fine granules in the cytoplasm", "B": "Koilocytes in the granular cell layer of the epidermis", "C": "Nests of melanocytes at the base of rete ridges and the dermis", "D": "Immature keratinocytes with small keratin-filled cysts", "E": "Fibroblast proliferation with small, benign dermal growth"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old man presents to the emergency department brought in by police. He was found shouting at strangers in the middle of the street. The patient has no significant past medical history, and his only medications include a short course of prednisone recently prescribed for poison ivy exposure. His temperature is 77°F (25°C), blood pressure is 90/50 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. The patient is only wearing underwear, and he is occasionally mumbling angrily about the government. He appears to be responding to internal stimuli, and it is difficult to obtain a history from him. Which of the following is the next best step in management?", "answer": "Warmed IV normal saline and warm blankets", "options": {"A": "Haloperidol IM", "B": "Lorazepam and discontinue steroids", "C": "Warm air recirculator", "D": "Risperidone and warm blankets", "E": "Warmed IV normal saline and warm blankets"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old man with coronary artery disease and hypertension comes to the emergency department because of intermittent retrosternal chest pain, lightheadedness, and palpitations. He has smoked one pack of cigarettes daily for 39 years. His pulse is 140/min and irregularly irregular, respirations are 20/min, and blood pressure is 108/60 mm Hg. An ECG shows an irregular, narrow-complex tachycardia with absent P waves. A drug with which of the following mechanisms of action is most likely to be effective in the long-term prevention of embolic stroke in this patient?", "answer": "Interference with carboxylation of glutamate residues", "options": {"A": "Binding and activation of antithrombin III", "B": "Irreversible inhibition of cyclooxygenase", "C": "Interference with carboxylation of glutamate residues", "D": "Activation of the conversion of plasminogen to plasmin", "E": "Irreversible blockade of adenosine diphosphate receptors"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old woman comes to the physician because of a 3-month history of intermittent palpitations and shortness of breath. Cardiopulmonary examination shows no other abnormalities. An ECG shows an absence of P waves, an oscillating baseline, and irregular RR intervals at a rate of approximately 95 beats per minute. The difference between atrial and ventricular rates in this patient is most likely due to which of the following?", "answer": "Temporary inactivation of Na+ channels in the AV node", "options": {"A": "Temporary inactivation of Na+ channels in the AV node", "B": "Inhibition of the Na+/K+-ATPase pump in ventricular cells", "C": "Transient activation of K+ current in Purkinje fibers", "D": "Limited speed of conduction through the left bundle branch", "E": "Prolonged influx through voltage-gated Ca2+ channels in the bundle of His"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old woman presents to the emergency department with abdominal and pelvic pain. She states it started 3 days ago and it has been getting gradually worse. She states it is diffuse and is located over her abdomen, pelvis, and inside her vagina. She also endorses vaginal pruritus and a discharge from her vagina. The patient works in an ice cream parlor and is sexually active with multiple different partners. Her temperature is 98.0°F (36.7°C), blood pressure is 122/80 mmHg, pulse is 82/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is notable for a foul smelling vagina with a thin, white discharge. Her abdomen is diffusely tender. The patient is noted to be itching her vagina during the exam. Which of the following is the most appropriate initial step in management?", "answer": "Urine hCG", "options": {"A": "Cervical swab and culture", "B": "CT abdomen/pelvis", "C": "KOH prep", "D": "Urine hCG", "E": "Wet mount"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old man presents to his primary care physician because he has been experiencing shortness of breath and cough. He began feeling short of breath when playing recreational soccer with his friends. Over time these episodes have become more severe. They now impair his ability to work as a construction worker. In addition, he has developed a chronic dry cough that has been increasing in intensity. Radiography reveals subpleural cystic enlargement, and biopsy reveals fibroblast proliferation in the affected tissues. Which of the following describes the mechanism of action for a drug that can cause a similar pattern of pulmonary function testing as would be seen in this disease?", "answer": "Dihydrofolate reductase inhibitor", "options": {"A": "Dihydrofolate reductase inhibitor", "B": "Microtubule inhibitor", "C": "Purine analogue", "D": "Pyrimidine analogue", "E": "Xanthine oxidase inhibitor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "While walking through a park with his wife, a 51-year-old man with type 2 diabetes mellitus develops nausea, sweating, pallor, and palpitations. For the past 3 weeks, he has been trying to lose weight and has adjusted his diet and activity level. He eats a low-carb diet and swims 3 times a week. The man returned home from a training session 2 hours ago. Current medications include basal insulin and metformin. Shortly before his wife returns from their car with his emergency medication kit, he becomes unconscious. Administration of which of the following is the most appropriate next step in management?", "answer": "Intramuscular glucagon", "options": {"A": "Sublingual nitroglycerine", "B": "Oral glucose", "C": "Intramuscular glucagon", "D": "Rectal lorazepam", "E": "Intra-arterial dextrose"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An x-ray of the chest is conducted and shown below. Which of the following is the most appropriate next step in management?", "answer": "Administer isoniazid for 9 months", "options": {"A": "Perform interferon-γ release assay", "B": "Administer isoniazid for 9 months", "C": "Administer isoniazid + rifampin + pyrazinamide + ethambutol", "D": "Repeat PPD skin test", "E": "Obtain a chest CT scan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old woman presents to her physician with a four-month history of headache. Her headache is nonfocal but persistent throughout the day without any obvious trigger. She was told that it was a migraine but has never responded to sumatriptan, oxygen, or antiemetics. She takes amlodipine for hypertension. She does not smoke. She denies any recent weight loss or constitutional symptoms. Her temperature is 98°F (36.7°C), blood pressure is 180/100 mmHg, pulse is 70/min, and respirations are 15/min. She is obese with posterior cervical fat pads and central abdominal girth. Her neurological exam is unremarkable. In her initial laboratory workup, her fasting blood glucose level is 200 mg/dL. The following additional lab work is obtained and is as follows:\n\nSerum:\nNa+: 142 mEq/L\nCl-: 102 mEq/L\nK+: 4.1 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 135 mg/dL\nCreatinine: 1.3 mg/dL\nCa2+: 10.0 mg/dL\nAST: 8 U/L\nALT: 8 U/L\n24-hour urinary cortisol: 500 µg (reference range < 300 µg)\nSerum cortisol: 25 µg/mL (reference range 5-23 µg/dL)\n24-hour low dose dexamethasone suppression test: Not responsive\nHigh dose dexamethasone suppression test: Responsive\nAdrenocorticotropin-releasing hormone (ACTH): 20 pg/mL (5-15 pg/mL)\n\nImaging reveals a 0.5 cm calcified pulmonary nodule in the right middle lobe that has been present for 5 years but an otherwise unremarkable pituitary gland, mediastinum, and adrenal glands. What is the best next step in management?", "answer": "Inferior petrosal sinus sampling", "options": {"A": "Repeat high dose dexamethasone suppression test", "B": "Inferior petrosal sinus sampling", "C": "Pituitary resection", "D": "CT-guided biopsy of the pulmonary nodule", "E": "Pulmonary nodule resection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "During the exam of a 2-day-old female neonate you determine that she appears lethargic, cyanotic, and has a coarse tremor of her right arm. The patient's mother explains that she observed what she believed to be seizure-like activity just before you arrived in the room. The mother has a history of type two diabetes mellitus and during childbirth there was a delay in cord clamping. You decide to get electrolytes and a complete blood count to work up this patient. The labs are significant for mild hypoglycemia and a hematocrit of 72%. What is the most effective treatment for this patient's condition?", "answer": "Partial exchange transfusion with hydration", "options": {"A": "Phlebotomy", "B": "Partial exchange transfusion with hydration", "C": "Fluid resuscitation", "D": "Hydroxyurea", "E": "Interferon alpha"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 75-year-old woman comes to the physician because of generalized weakness for 6 months. During this period, she has also had a 4-kg (8.8-lb) weight loss and frequent headaches. She has been avoiding eating solids because of severe jaw pain. She has hypertension and osteoporosis. She underwent a total left-sided knee arthroplasty 2 years ago because of osteoarthritis. The patient does not smoke or drink alcohol. Her current medications include enalapril, metoprolol, low-dose aspirin, and a multivitamin. She appears pale. Her temperature is 37.5°C (99.5°F), pulse is 82/min, and blood pressure is 135/80 mm Hg. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 10 g/dL\nMean corpuscular volume 87 μm3\nLeukocyte count 8,500/mm3\nPlatelet count 450,000/mm3\nErythrocyte sedimentation rate 90 mm/h\nWhich of the following is the most appropriate next step in management?\"", "answer": "Oral prednisone and temporal artery biopsy", "options": {"A": "Intravenous methylprednisolone only", "B": "Oral prednisone only", "C": "Intravenous methylprednisolone and temporal artery biopsy", "D": "Oral prednisone and temporal artery biopsy", "E": "Temporal artery biopsy only\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old primigravida at 28 weeks gestation presents to the office stating that she “can’t feel her baby kicking anymore.” She also noticed mild-to-moderate vaginal bleeding. A prenatal visit a few days ago confirmed the fetal cardiac activity by Doppler. The medical history is significant for GERD, hypertension, and SLE. The temperature is 36.78°C (98.2°F), the blood pressure is 125/80 mm Hg, the pulse is 70/min, and the respiratory rate is 14/min. Which of the following is the next best step in evaluation?", "answer": "Confirmation of cardiac activity by Doppler", "options": {"A": "Abdominal delivery", "B": "Confirmation of cardiac activity by Doppler", "C": "Speculum examination", "D": "Misoprostol", "E": "Order platelet count, fibrinogen, PT and PTT levels"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 47-year-old woman comes to her primary care doctor because of a new, pruritic rash. She was gardening in her yard two days ago and now has an eczematous papulovesicular rash on both ankles. You also note a single, 5 mm brown lesion with a slightly raised border on her left thigh. You prescribe a topical corticosteroid for contact dermatitis. Which of the following is the appropriate next step for the thigh lesion?", "answer": "Further questioning", "options": {"A": "Further questioning", "B": "Topical corticosteroid", "C": "Reassurance", "D": "Simple shave biopsy", "E": "Full thickness biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old man presents to the emergency department with vomiting. He states that he has experienced severe vomiting starting last night that has not been improving. He states that his symptoms improve with hot showers. The patient has presented to the emergency department with a similar complaints several times in the past as well as for intravenous drug abuse. His temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 110/min, respirations are 22/min, and oxygen saturation is 98% on room air. Physical exam is deferred as the patient is actively vomiting. Which of the following is associated with the most likely diagnosis?", "answer": "Marijuana use", "options": {"A": "Alcohol use", "B": "Marijuana use", "C": "Substance withdrawal", "D": "Toxin ingestion", "E": "Viral gastroenteritis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old female presents to your office complaining of several brief episodes of shortness of breath of varying severity. Which of the following substances would lead to a decrease in FEV1 of 20% if the patient has asthma?", "answer": "Methacholine", "options": {"A": "Methacholine", "B": "Epinephrine", "C": "Ipratroprium", "D": "Norepinephrine", "E": "Albuterol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 59-year-old man presents to his primary care physician with a 5-month history of breathing difficulties. He says that he has been experiencing exertional dyspnea that is accompanied by a nonproductive cough. His past medical history is significant for a solitary lung nodule that was removed surgically 10 years ago and found to be benign. He works as a secretary for a coal mining company, does not smoke, and drinks socially with friends. His family history is significant for autoimmune diseases. Physical exam reveals fine bibasilar inspiratory crackles in both lungs, and laboratory testing is negative for antinuclear antibody and rheumatoid factor. Which of the following is associated with the most likely cause of this patient's symptoms?", "answer": "Subpleural cystic enlargement", "options": {"A": "Anticancer agents", "B": "Interstitial lymphoid infiltrates in lung tissue", "C": "Proteinaceous material in the alveoli", "D": "Subpleural cystic enlargement", "E": "Type III hypersensitivity reaction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old woman comes to the physician because of a 1-month history of persistent abdominal cramping, diarrhea, and rectal pain. During the past 2 weeks, she has had up to 4 small volumed, blood-tinged stools with mucus daily. She has also had intermittent fevers and a 4.5-kg (10-lb) weight loss during this time. She traveled to Southeast Asia 3 months ago and received all appropriate vaccinations and medications beforehand. She has no history of serious illness and takes no medications. Her temperature is 37.2°C (99°F), pulse is 90/min, respirations are 16/min, and blood pressure is 125/80 mm Hg. The abdomen is soft, and there is tenderness to palpation of the left lower quadrant with guarding but no rebound. Bowel sounds are normal. The stool is brown, and a test for occult blood is positive. Flexible sigmoidoscopy shows a granular, hyperemic, and friable rectal mucosa that bleeds easily on contact. Which of the following is this patient at greatest risk of developing?", "answer": "Colorectal cancer", "options": {"A": "Hemolytic uremic syndrome", "B": "Oral ulcers", "C": "Gastric cancer", "D": "Colorectal cancer", "E": "Colonic granulomas"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old man comes to the emergency department because of recurrent episodes of vomiting for 1 day. He has had over 15 episodes of bilious vomiting. During this period he has had cramping abdominal pain but has not had a bowel movement or passed flatus. He does not have fever or diarrhea. He was diagnosed with Crohn disease at the age of 28 years which has been well controlled with oral mesalamine. He underwent a partial small bowel resection for midgut volvulus at birth. His other medications include vitamin B12, folic acid, loperamide, ferrous sulfate, and vitamin D3. He appears uncomfortable and his lips are parched. His temperature is 37.1°C (99.3°F), pulse is 103/min, and blood pressure is 104/70 mm Hg. The abdomen is distended, tympanitic, and tender to palpation over the periumbilical area and the right lower quadrant. Rectal examination is unremarkable. A CT scan of the abdomen shows multiple dilated loops of small bowel with a transition zone in the mid to distal ileum. After 24 hours of conservative management with IV fluid resuscitation, nasogastric bowel decompression, promethazine, and analgesia, his condition does not improve and a laparotomy is scheduled. During the laparotomy, two discrete strictures are noted in the mid-ileum, around 20 cm apart. Which of the following is the most appropriate next step in management?", "answer": "Strictureplasty of individual strictures", "options": {"A": "Ileocolectomy", "B": "Strictureplasty of individual strictures", "C": "Small bowel resection and primary anastomosis", "D": "Abdominal closure and start palliative care", "E": "Small bowel resection with ileostomy\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old gravida 4 para 1 presents to the emergency department with sudden severe abdominal pain and mild vaginal bleeding. Her last menstrual period was 12 weeks ago. She describes her pain as similar to uterine contractions. She has a history of 2 spontaneous abortions in the first trimester. She is not complaining of dizziness or dyspnea. On physical examination, the temperature is 36.9°C (98.4°F), the blood pressure is 120/85 mm Hg, the pulse is 95/min, and the respiratory rate is 17/min. The pelvic examination reveals mild active bleeding and an open cervical os. There are no clots. Transvaginal ultrasound reveals a fetus with no cardiac activity. She is counseled about the findings and the options are discussed. She requests to attempt medical management with mifepristone before progressing to surgical intervention. Which of the following describes the main mechanism of action for mifepristone?", "answer": "Increase myometrial sensitivity to contractions and induced decidual breakdown", "options": {"A": "Induce teratogenesis in the fetus", "B": "Induce cervical dilation", "C": "Increase myometrial sensitivity to contractions and induced decidual breakdown", "D": "Interferes with cell growth in rapidly dividing cells", "E": "Interferes with placental blood supply to the fetus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man presents to his family physician for a routine exam. He feels well and reports no new complaints since his visit last year. Last year, he had a colonoscopy which showed no polyps, a low dose chest computerized tomography (CT) scan that showed no masses, and routine labs which showed a fasting glucose of 93 mg/dL. He is relatively sedentary and has a body mass index (BMI) of 24 kg/m^2. He has a history of using methamphetamines, alcohol (4-5 drinks per day since age 30), and tobacco (1 pack per day since age 18), but he joined Alcoholics Anonymous and has been in recovery, not using any of these for the past 7 years. Which of the following is indicated at this time?", "answer": "Chest computerized tomography (CT) scan", "options": {"A": "Abdominal ultrasound", "B": "Chest computerized tomography (CT) scan", "C": "Colonoscopy", "D": "Chest radiograph", "E": "Fasting glucose"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man presents to his primary care physician for a wellness visit. He says that he has been experiencing episodes of chest pain and lightheadedness. Approximately 1 week ago he fell to the ground after abruptly getting up from the bed. Prior to the fall, he felt lightheaded and his vision began to get blurry. According to his wife, he was unconscious for about 5 seconds and then spontaneously recovered fully. He experiences a pressure-like discomfort in his chest and lightheadedness with exertion. At times, he also experiences shortness of breath when climbing the stairs. Medical history is significant for hypertension and hypercholesterolemia. He does not smoke cigarettes or drink alcohol. Cardiac auscultation demonstrates a systolic ejection murmur at the right upper border and a normal S1 and soft S2. Which of the following is most likely found in this patient?", "answer": "Increased blood flow velocity through the aortic valve", "options": {"A": "Bicuspid aortic valve", "B": "Decreased murmur intensity with squatting", "C": "High bounding pulses", "D": "Increased blood flow velocity through the aortic valve", "E": "Pulsus paradoxus"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old G1P1001 presents for her 6-week postpartum visit after delivering a male infant by spontaneous vaginal delivery at 41 weeks and 5 days gestation. She notes that five days ago, her right breast began to hurt, and the skin near her nipple turned red. She also states that she has felt feverish and generally achy for 2 days but thought she was just sleep deprived. The patient’s son has been having difficulty latching for the last 2 weeks and has begun receiving formula in addition to breast milk, though the patient wishes to continue breastfeeding. She is generally healthy with no past medical history but has smoked half a pack per day for the last 15 years. Her mother died from breast cancer at the age of 62, and her father has hypertension and coronary artery disease. At this visit, her temperature is 100.6° F (38.1° C), blood pressure is 116/73 mmHg, pulse is 80/min, and respirations are 14/min. She appears tired and has a slightly flat affect. Examination reveals a 4x4 cm area of erythema on the lateral aspect near the nipple on the right breast. In the center of this area, there is a fluctuant, tender mass that measures 2x2 cm. The overlying skin is intact. The remainder of her exam is unremarkable. Which of the following is the best next step in management?", "answer": "Needle aspiration and oral dicloxacillin", "options": {"A": "Mammogram", "B": "Incision and drainage", "C": "Cessation of breastfeeding", "D": "Needle aspiration and oral dicloxacillin", "E": "Cessation of smoking"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 66-year-old woman with hypertension comes to the physician because of crampy, dull abdominal pain and weight loss for 1 month. The pain is located in the epigastric region and typically occurs within the first hour after eating. She has had a 7-kg (15.4-lb) weight loss in the past month. She has smoked 1 pack of cigarettes daily for 20 years. Physical examination shows a scaphoid abdomen and diffuse tenderness to palpation. Laboratory studies including carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), and lipase concentrations are within the reference range. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Narrowing of the celiac artery", "options": {"A": "Narrowing of the celiac artery", "B": "Malignant mass at the head of the pancreas", "C": "Embolus in the superior mesenteric artery", "D": "Focal wall thickening in the colon", "E": "Decreased motility of gastric smooth muscle"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old woman makes an appointment with her physician to discuss the results of her cervical cancer screening. She has been menopausal for  2 years and does not take hormone replacement therapy. Her previous Pap smear showed low-grade squamous intraepithelial lesion (LSIL); no HPV testing was performed. Her gynecologic examination is unremarkable. The results of her current Pap smear is as follows:\nSpecimen adequacy satisfactory for evaluation\nInterpretation low-grade squamous intraepithelial lesion\nNotes atrophic pattern\nWhich option is the next best step in the management of this patient?", "answer": "Colposcopy", "options": {"A": "Reflex HPV testing", "B": "Test for HPV 16 and 18", "C": "Colposcopy", "D": "Immediate loop excision", "E": "Repeat HPV testing in 6 months"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 19-year-old woman is brought to the physician by her parents because of irritable mood that started 5 days ago. Since then, she has been staying up late at night working on a secret project. She is energetic despite sleeping less than 4 hours per day. Her parents report that she seems easily distracted. She is usually very responsible, but this week she spent her paycheck on supplies for her project. She has never had similar symptoms before. In the past, she has had episodes where she felt too fatigued to go to school and slept until 2 pm every day for 2 weeks at a time. During those times, her parents noticed that she cried excessively, was very indecisive, and expressed feelings of worthlessness. Two months ago, she had an asthma exacerbation and was treated with bronchodilators and steroids. She tried cocaine once in high school but has not used it since. Vital signs are within normal limits. On mental status examination, she is irritable but cooperative. Her speech is pressured and her thought process is linear. Which of the following is the most likely diagnosis?", "answer": "Bipolar II disorder", "options": {"A": "Bipolar II disorder", "B": "Bipolar I disorder", "C": "Major depressive disorder", "D": "Schizoaffective disorder", "E": "Substance abuse"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 36-year-old man presents with massive hematemesis. Past medical history is significant for a gastric ulcer. He has a pulse of 115/min, respiratory rate of 20/min, temperature of 36°C (96.8°F), and blood pressure of 90/59 mm Hg. The patient receives a transfusion of 2 units of packed red blood cells. Around 5–10 minutes after the transfusion, he starts having chills, pain in the lumbar region, and oliguria. His vital signs change to pulse of 118/min, respiratory rate of 19/min, temperature of 38°C (100.4°F), and blood pressure of 60/40 mm Hg. Which of the following is the most likely cause of this patient’s condition?", "answer": "Acute hemolytic transfusion reaction", "options": {"A": "Acute hemolytic transfusion reaction", "B": "Anaphylactic transfusion reaction", "C": "Febrile non-hemolytic transfusion reaction", "D": "Transfusion-associated sepsis", "E": "Transfusion-related acute lung injury"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-day-old neonate is brought to the pediatrician by his parents for yellow skin for the past few days. His parents also reported that he remains quiet all day and does not even respond to sound. Further perinatal history reveals that he was born by cesarean section at 36 weeks of gestation, and his birth weight was 2.8 kg (6.1 lb). This baby is the second child of this couple, who are close relatives. Their first child died as the result of an infection at an early age. His temperature is 37.0°C (98.6°F), pulse is 116/min, and respirations are 29/min. On physical examination, hypotonia is present. His laboratory studies show:\nHemoglobin 12.9 gm/dL\nLeukocyte count 9,300/mm3\nPlatelet count 170,000/mm3\nUnconjugated bilirubin 33 mg/dL\nConjugated bilirubin 0.9 mg/dL\nCoombs test Negative\nWhich of the following is the most appropriate next step?", "answer": "Liver transplantation", "options": {"A": "No treatment is required\nrnrn", "B": "Phenobarbital", "C": "Phototherapy", "D": "Liver transplantation", "E": "Discontinue the breast feeding"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old boy presents to the pediatrician after his parents noted that he could not sustain physical exertion and would experience muscle cramping. It was noted that after physical exertion the boy experienced severe muscle pain. After a series of biochemical and genetic tests, it was discovered the that the boy had a nonsense mutation in the gene encoding the muscle glycogen phosphorylase. Thus he was diagnosed with McArdle's disease. Which of the following mRNA changes would be expected to cause this mutation?", "answer": "UAU -> UAA", "options": {"A": "UGU -> CGC", "B": "AUG -> UCA", "C": "CUG -> AUG", "D": "UGA -> UAG", "E": "UAU -> UAA"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old man presents to the emergency department with difficulty breathing for the past 3 hours. He also mentions that over the last week he was frequently breathless and fatigued after walking a few blocks. He has had diabetes mellitus and hypertension for the past 10 years, and his regular medications include metformin, glipizide, and lisinopril. However, he did not take his medications last week due to unplanned travel. Review of his medical records reveals an episode of acute viral hepatitis about 6 months ago from which he recovered well. His temperature is 37.0°C (98.6°F), the pulse is 108/min, the blood pressure is 170/94 mm Hg, and the respiratory rate is 24/min. On physical examination, periorbital edema is present with pitting edema over both ankles and pretibial regions. Pallor and icterus are absent. Auscultation of the chest reveals crackles over the infrascapular regions bilaterally. Abdominal examination shows tender hepatomegaly. Which of the following is the most likely diagnosis?", "answer": "Acute decompensated heart failure", "options": {"A": "Acute hepatic failure", "B": "Diabetic ketoacidosis", "C": "Acute decompensated heart failure", "D": "Pulmonary embolism", "E": "Acute renal failure"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl comes to the physician because of left lower abdominal pain for 1 day. She describes the pain as 6 out of 10 in intensity. Over the past 5 months, she has had similar episodes of pain that occur once a month and last 1 to 2 days. Menses occur at regular 28-day intervals and last 5 to 6 days. Menarche was at the age of 13 years, and her last menstrual period was 2 weeks ago. She has been sexually active with 1 male partner in the past and has used condoms inconsistently. She tested negative for sexually transmitted infections on her last visit 6 months ago. Abdominal and pelvic examination shows no abnormalities. A urine pregnancy test is negative. Which of the following is the most appropriate next step in the management of this patient's symptoms?", "answer": "Reassurance", "options": {"A": "CT scan of the pelvis", "B": "Diagnostic laparoscopy", "C": "Reassurance", "D": "Combined oral contraceptive pill", "E": "Pelvic ultrasonography\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 6-month-old boy is brought to the physician for a well-child examination. The boy was born at term, and the pregnancy was complicated by prolonged labor. There is no family history of any serious illnesses. He can sit upright but needs help to do so and cannot roll over from the prone to the supine position. He can pull himself to stand. He can grasp his rattle and can transfer it from one hand to the other. He babbles. He cries if anyone apart from his parents holds him or plays with him. He touches his own reflection in the mirror. Vital signs are within normal limits. He is at the 40th percentile for head circumference, 30th percentile for length, and 40th percentile for weight. Physical examination reveals no abnormalities. Which of the following developmental milestones is delayed in this infant?", "answer": "Gross motor", "options": {"A": "Cognitive", "B": "Fine motor", "C": "Gross motor", "D": "Language", "E": "Social"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old woman with HIV comes to the emergency department because of fever and multiple skin lesions for 1 week. She also has nausea, anorexia, and abdominal pain. The skin lesions are non-pruritic and painless. She has smoked one pack of cigarettes daily for 15 years and drinks 2 beers daily. She has been using intravenous crack cocaine for 6 years. She appears ill. Her temperature is 38°C (100.4°F), pulse is 105/min, blood pressure is 110/75 mm Hg. Her BMI is 19 kg/m2. Examination shows track marks on both cubital fossae. There are white patches on her palate that can be scraped off. There are several red papules measuring 1 to 2 cm on her face and trunk. Her CD4+T-lymphocyte count is 98/mm3 (N ≥ 500). Biopsy of a skin lesion shows vascular proliferation and small black bacteria on Warthin-Starry stain. Which of the following is the most appropriate pharmacotherapy?", "answer": "Erythromycin", "options": {"A": "Pyrimethamine and sulfadiazine", "B": "Vinblastine", "C": "Azithromycin and ethambutol", "D": "Erythromycin", "E": "Nitazoxanide"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 63-year-old man presents to the emergency department because of progressive difficulty with breathing. He has a history of diabetes, hypertension, and chronic bronchitis. He has been receiving medications to moderate his conditions and reports being compliant with his schedule. He reports a recent difficulty with tackling simple chores in the house. He has not been able to walk for more than 1 block over the past few days. His persistent cough has also been worsening with more formation of sputum. During his diagnosis of bronchitis, about a year ago, he had a 40-pack-year smoking history. The patient is in evident distress and uses his accessory muscles to breathe. The vital signs include: temperature 38.6°C (101.5°F), blood pressure 120/85 mm Hg, pulse 100/min, respiratory rate 26/min, and oxygen (O2) saturation 87%. A decrease in breathing sounds with expiratory wheezes is heard on auscultation of the heart. The arterial blood gas (ABG) analysis shows:\nPCO2 60 mm Hg\nPO2 45 mm Hg\npH 7.3\nHCO3– 25 mEq/L\nWhich of the following is the most appropriate next step in the treatment?", "answer": "O2 supplementation", "options": {"A": "Albuterol", "B": "Methylprednisolone", "C": "Levofloxacin", "D": "O2 supplementation", "E": "Aminophylline"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old girl is brought to the physician for a well-child examination. She is at 95th percentile for height and 70th percentile for weight. Examination shows elevated breast buds that extend beyond the areola. Coarse pubic and axillary hair is present. The external genitalia appear normal. An x-ray of the left wrist shows a bone age of 10 years. Serum luteinizing hormone levels do not increase following GnRH agonist stimulation. Which of the following is the most likely cause of these findings?", "answer": "Granulosa cell tumor", "options": {"A": "Granulosa cell tumor", "B": "Ovarian fibroma", "C": "McCune-Albright syndrome", "D": "Hypothalamic glioma", "E": "Congenital adrenal hyperplasia\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A researcher is investigating the effects of a new antihypertensive medication on renal physiology. She gives a subject a dose of the new medication, and she then collects plasma and urine samples. She finds the following: Hematocrit: 40%; Serum creatinine: 0.0125 mg/mL; Urine creatinine: 1.25 mg/mL. Urinary output is 1 mL/min. Renal blood flow is 1 L/min. Based on the above information and approximating that the creatinine clearance is equal to the GFR, what answer best approximates filtration fraction in this case?", "answer": "17%", "options": {"A": "10%", "B": "25%", "C": "17%", "D": "50%", "E": "33%"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 71-year-old man with asthma and dementia presents to the emergency department in acute respiratory distress. He is with his home care nurse who explains that he has been hiding his bronchodilators for the past 3 weeks, and she has had to dutifully look for them and help him administer them. Over the past 2 days, however, she has been completely unsuccessful in finding his medication and was in the process of contacting his primary care physician for a refill of his prescription when he suddenly had a ‘coughing fit’ and began wheezing uncontrollably. The patient is obviously uncomfortable and is using accessory muscles of respiration to catch his breath. He is struggling to speak and is immediately given multiple doses of nebulized albuterol and intravenous methylprednisolone; however, his condition does not improve. The arterial blood gas test result shows pH 7.20. He is subsequently intubated and sent to the intensive care unit (ICU). In patients who are intubated for mechanical ventilation, there is an increased risk for ventilator-associated pneumonia. Which of the following should be prophylactically given to this patient to lower his risk for pneumonia?", "answer": "Sucralfate", "options": {"A": "Ranitidine", "B": "Sucralfate", "C": "Clarithromycin", "D": "Ceftazidime", "E": "Omeprazole"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "The serum brain natriuretic peptide and N-terminal pro-BNP are elevated. A diagnosis of heart failure with preserved ejection fraction is made. In addition to supplemental oxygen therapy, which of the following is the most appropriate initial step in management?", "answer": "Intravenous furosemide therapy\n\"", "options": {"A": "Intermittent hemodialysis", "B": "Intravenous morphine therapy", "C": "Thoracentesis", "D": "Intravenous dobutamine", "E": "Intravenous furosemide therapy\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 53-year-old female presents with worsening shortness of breath with activity. Physical exam reveals a diastolic murmur with an opening snap. The patient’s medical history is significant for a left hip replacement 10 years ago, and she vaguely recalls an extended period of illness as a child described as several severe episodes of sore throat followed by rash, fever, and joint pains. Administration of which of the following treatments at that time would have been most effective in reducing her risk of developing cardiac disease?", "answer": "Penicillin", "options": {"A": "Acyclovir", "B": "Penicillin", "C": "Vancomycin", "D": "Aspirin", "E": "Ciprofloxacin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 69-year-old woman with acute myeloid leukemia comes to the physician to discuss future treatment plans. She expresses interest in learning more about an experimental therapy being offered for her condition. After the physician explains the mechanism of the drug and describes the risks and benefits, the patient then states that she is not ready to die. When the physician asks her what her understanding of the therapy is, she responds “I don't remember the details, but I just know that I definitely want to try it, because I don't want to die.” Which of the following ethical principles is compromised in this physicians' interaction with the patient?", "answer": "Decision-making capacity", "options": {"A": "Therapeutic privilege", "B": "Patient autonomy", "C": "Decision-making capacity", "D": "Information disclosure", "E": "Patient competence"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 22-year-old man has had dyspnea and hemoptysis for the past week. He has no known sick contacts. There is no personal or family history of serious illness. He takes no medications. His temperature is 37°C (98.6°F), pulse is 82/min, respirations are 22/min, and blood pressure is 152/90 mm Hg. Examination shows inspiratory crackles at both lung bases. The remainder of the examination shows no abnormalities. His hemoglobin is 14.2 g/dL, leukocyte count is 10,300/mm3, and platelet count is 205,000/mm3. Urinalysis shows a proteinuria of 2+, 70 RBC/hpf, and 1–2 WBC/hpf. Chest x-ray shows pulmonary infiltrates. Further evaluation is most likely to show which of the following findings?", "answer": "Increased anti-GBM antibody titers", "options": {"A": "Increased anti-GBM antibody titers", "B": "Increased serum IgA titers", "C": "Increased c-ANCA titers", "D": "Increased p-ANCA titers", "E": "Increased anti-dsDNA antibody titers"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old man comes to the emergency department for severe, acute right leg pain. The patient's symptoms began suddenly 4 hours ago, while he was reading the newspaper. He has poorly-controlled hypertension and osteoarthritis. He has smoked one pack of cigarettes daily for 31 years. Current medications include lisinopril, metoprolol succinate, and ibuprofen. He appears to be in severe pain and is clutching his right leg. His temperature is 37.4°C (99.3°F), pulse is 102/min and irregularly irregular, respirations are 19/min, and blood pressure is 152/94 mm Hg. The right leg is cool to the touch, with decreased femoral, popliteal, posterior tibial, and dorsalis pedis pulses. There is moderate weakness and decreased sensation in the right leg. An ECG shows absent P waves and a variable R-R interval. Right leg Doppler study shows inaudible arterial signal and audible venous signal. Angiography shows 90% occlusion of the right common femoral artery. In addition to initiating heparin therapy, which of the following is the most appropriate next step in management?", "answer": "Balloon catheter embolectomy", "options": {"A": "Open embolectomy", "B": "Balloon catheter embolectomy", "C": "Amputation of the affected limb", "D": "Surgical bypass of the affected vessel", "E": "Percutaneous transluminal angioplasty"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man comes to the physician because of intermittent lower back pain for 1 week. His symptoms began shortly after lifting heavy boxes at work. He has not had any fever, chills, or weight loss. He has a history of peptic ulcer disease. He does not smoke or drink alcohol. His vital signs are within normal limits. Examination shows mild paraspinal lumbar tenderness. Neurologic examination shows no focal findings. An x-ray of the spine shows no abnormalities. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Acetaminophen", "options": {"A": "Aspirin", "B": "Acetaminophen", "C": "Oxycodone", "D": "Naproxen", "E": "Ibuprofen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old man presents to his primary care physician complaining of headaches. He states that over the past month he has been trying to study for an accounting exam, but he finds it increasingly more difficult to focus due to his headaches. He also complains of lower extremity muscle cramping. He has no significant past medical history and takes ibuprofen and acetaminophen as needed. The patient’s temperature is 98°F (36.7°C), blood pressure is 168/108 mmHg, and pulse is 75/min. Labs are obtained, as shown below:\n\nSerum:\npH (VBG): 7.50\nNa: 146 mEq/L\nK+: 3.2 mEq/L\nCl-: 104 mEq/L\nHCO3-: 32 mEq/L\nUrea nitrogen: 20 mg/dL\nCreatinine: 1.1 mg/dL\nGlucose: 85 mg/dL\n\nAn ultrasound reveals a hypoechoic lesion within the right adrenal gland. A 2 cm right-sided homogeneous adrenal mass is confirmed with computed tomography. Which of the following findings is associated with the patient’s most likely diagnosis?", "answer": "Low plasma renin", "options": {"A": "Elevated 17-hydroxyprogesterone", "B": "High adrenocorticotropic hormone", "C": "High plasma renin", "D": "Low aldosterone level", "E": "Low plasma renin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old woman presents to the emergency department with a throbbing headache. She states that the pain is worse when eating and is localized over the right side of her head. Review of systems is only notable for some blurry vision in the right eye which is slightly worse currently. The patient's past medical history is notable only for chronic pain in her muscles and joints for which she has been taking ibuprofen. Her temperature is 99.1°F (37.3°C), blood pressure is 144/89 mmHg, pulse is 87/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical examination is significant for tenderness to palpation over the right temporal region. Which of the following is the best initial step in management?", "answer": "Methylprednisolone", "options": {"A": "100% oxygen", "B": "CT head", "C": "Ibuprofen and acetaminophen", "D": "Methylprednisolone", "E": "MRI head"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old Caucasian female presents to the emergency department with complaints of a new-onset, right-sided throbbing headache which becomes markedly worse when eating. The daughter also reports that her mother has recently had difficulties with performing daily activities, such as climbing stairs or standing up. Past medical history is significant for a lower extremity deep vein thrombosis. The blood pressure is 124/78 mm Hg, the heart rate is 72/min, and the respiratory rate is 15/min. The physical examination is unremarkable except for the right visual field defect. Laboratory results are presented below:\nHemoglobin 11.3 g/dL\nHematocrit 37.7%\nLeukocyte count 6,200/mm3\nMean corpuscular volume 82.2 μm3\nPlatelet count 200,000/mm3\nErythrocyte sedimentation rate 75 mm/h\nC-reactive protein 50 mg/dL\nWhich of the following medications would be most beneficial for this patient?", "answer": "Prednisolone", "options": {"A": "Low-molecular weight heparin ", "B": "Gabapentin", "C": "Celecoxib", "D": "Prednisolone", "E": "Methotrexate"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old woman presents to the office with the complaint of a tingling sensation over her face and distal parts of her lower limbs. Three weeks ago, she had an episode of bloody diarrhea and was successfully treated with erythromycin. She is a full-time radiology technician. Currently, she takes oral contraceptives and zopiclone (1 mg) at bedtime. Her blood pressure is 100/80 mm Hg, her heart rate is 91/min, her respiratory rate is 15/min, and her temperature is 36.7°C (98.0°F). Neurological examination reveals loss of all sensation over the face and in the distal part of her lower limbs. Strength in calf flexor and extensor muscles is diminished bilaterally (4/5 on all of the muscle groups). Deep tendon reflexes are 1+ in the knees and 1+ in the ankles. Plantar reflexes are flexor. What is the most probable mechanism of the pathological findings in this patient?", "answer": "Antibody-mediated destruction of peripheral myelin by cytotoxic cells", "options": {"A": "Antibody-mediated destruction of peripheral myelin by cytotoxic cells", "B": "Direct damage to myelin caused by diarrhea causing organism", "C": "Granulomatous alteration of the vessels supplying peripheral nerves", "D": "Radiation-induced oxidative stress in the neurons of dorsal ganglia", "E": "Failure of Schwann cells to produce myelin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 12-year-old girl is brought to the physician by her mother 2 hours after cutting her hand while playing in the yard. Examination of the right hand shows a 2-cm laceration on the thenar region of the palm with some surrounding tenderness and erythema. The right palm appears mildly swollen in comparison to the left. In response to this patient's injury, the endothelial cells lining the blood vessels of the affected area express increased numbers of cellular adhesion molecules. Which of the following mediators is most likely directly responsible for the described change?", "answer": "Interleukin-1", "options": {"A": "Interleukin-10", "B": "Interferon alpha", "C": "Interleukin-1", "D": "Interleukin-6", "E": "Interferon gamma\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3-week-old male is brought to the emergency department because of increasing lethargy. He was born at home without prenatal care or neonatal screening and appeared to be normal at birth. Despite this, his parents noticed that he would vomit after breastfeeding. He then progressively became more lethargic and began to have a few episodes of diarrhea after feeding. His parents do not recall any significant family history and neither of his siblings have had similar symptoms. Upon presentation, the infant is found to be generally unresponsive with mild hepatomegaly. Physical exam further reveals signs of clouding in the lenses of his eyes bilaterally. The levels of which of the following metabolites will be most dramatically elevated in this patient?", "answer": "Galactose-1-phosphate", "options": {"A": "Galactose", "B": "Galactose-1-phosphate", "C": "Fructose", "D": "Fructose-1-phosphate", "E": "Lactose"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-year-old boy is brought to the physician by his mother for the evaluation of abdominal pain and trouble sleeping for the past 6 months. His mother says he complains of crampy abdominal pain every morning on school days. He started attending a new school 7 months ago and she is concerned because he has missed school frequently due to the abdominal pain. He also has trouble falling asleep at night and asks to sleep in the same room with his parents every night. He has not had fever, vomiting, diarrhea, or weight loss. He sits very close to his mother and starts to cry when she steps out of the room to take a phone call. Abdominal examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Separation anxiety disorder", "options": {"A": "Separation anxiety disorder", "B": "Normal behavior", "C": "Irritable bowel syndrome", "D": "Conduct disorder", "E": "Acute stress disorder"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 69-year old male presents to the Emergency Department with bilious vomiting that started within the past 24 hours. His medical history is significant for hypertension, hyperlipidemia, and a myocardial infarction six months ago. His past surgical history is significant for a laparotomy 20 years ago for a perforated diverticulum. Most recently he had some dental work done and has been on narcotic pain medicine for the past week. He reports constipation and obstipation. He is afebrile with a blood pressure of 146/92 mm Hg and a heart rate of 116/min. His abdominal exam reveals multiple well-healed scars with distension but no tenderness. An abdominal/pelvic CT scan reveals dilated small bowel with a transition point to normal caliber bowel distally. When did the cause of his pathology commence?", "answer": "20 years ago", "options": {"A": "At birth", "B": "24 hours ago", "C": "One week ago", "D": "Six months ago", "E": "20 years ago"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 52-year-old woman comes to the physician because of vaginal itchiness and urinary frequency for the past 1 year. She stopped having vaginal intercourse with her husband because it became painful and occasionally resulted in vaginal spotting. Her last menstrual cycle was 14 months ago. She has vitiligo. Her only medication is a topical tacrolimus ointment. Her temperature is 37.1°C (98.8°F), pulse is 85/min, and blood pressure is 135/82 mm Hg. Examination shows multiple white maculae on her forearms, abdomen, and feet. Pelvic examination shows scarce pubic hair, vulvar pallor, and narrowing of the vaginal introitus. Which of the following most likely contributes to this patient's current symptoms?", "answer": "Thinning of the mucosa", "options": {"A": "Thinning of the mucosa", "B": "Inflammation of the vestibular glands", "C": "Decrease of pH", "D": "Dysplasia of the epithelium", "E": "Sclerosis of the dermis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old woman presents to the obstetrics ward to deliver her baby. The obstetrician establishes a pudendal nerve block via intravaginal injection of lidocaine near the tip of the ischial spine. From which of the following nerve roots does the pudendal nerve originate?", "answer": "S2-S4", "options": {"A": "L3-L4", "B": "L4-L5", "C": "L5-S1", "D": "L5-S2", "E": "S2-S4"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 25-year-old woman presents to her primary care physician for her yearly physical exam. She has no past medical history and says that she does not currently have any health concerns. On physical exam, she is found to have hyperactive patellar reflexes but says that she has had this finding since she was a child. She asks her physician why this might be the case. Her physician explains that there are certain cells that are responsible for detecting muscle stretch and responding to restore the length of the muscle. Which of the following is most likely a characteristic of these structures?", "answer": "They are in parallel with extrafusal skeletal muscle fibers", "options": {"A": "They activate inhibitory interneurons", "B": "They are in parallel with extrafusal skeletal muscle fibers", "C": "They are in series with extrafusal skeletal muscle fibers", "D": "They are innervated by group Ib afferent neurons", "E": "They inhibit the activity of alpha-motoneurons"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-month-old boy is brought to the physician for a routine follow-up examination. He was delivered at 32 weeks' gestation to a 35-year-old woman. Cardiac examination is shown. Which of the following is the most likely cause for this patient's findings?", "answer": "Patent ductus arteriosus", "options": {"A": "Patent ductus arteriosus", "B": "Ventricular septal defect", "C": "Atrial septal defect", "D": "Mitral valve prolapse", "E": "Tetralogy of Fallot"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 61-year-old woman is brought to an urgent care clinic by her husband with an altered mental status. The patient’s husband says that her symptoms onset acutely 24 hours ago. He says she suddenly started to feel excessively drowsy and quickly became altered. Past medical history is significant for renal transplant 18 months ago, well-managed with immunosuppressive medication. The vital signs include: temperature 39.4°C (103.0°F), blood pressure 85/50 mm Hg, pulse 135/min and respirations 24/min. On physical examination, the patient is arousable but non-responsive to commands. Oriented x 0. Glasgow Coma Scale (GCS) score is 10/15. Multiple black skin lesions are present on the trunk. Lesions are approximately 4 cm is diameter and round with a necrotic center forming an eschar. Laboratory findings are significant for the following:\nHemoglobin 14.2 g/dL\nWBC count 3,700/µL\nNeutrophils 22%\nLymphocytes 52%\nMonocytes 17%\nEosinophils 5%\nBasophils 4%\nPlatelets 179,000/µL\nBUN 15 mg/dL\nCreatinine 0.8 mg/dL\nBlood cultures are positive for Pseudomonas aeruginosa. Which of the following factors is most likely responsible for this patient’s condition?", "answer": "Decreased phagocytic cell count", "options": {"A": "Failure of trimethoprim/sulfamethoxazole prophylactic therapy", "B": "Failure of immunosuppressive therapy", "C": "Decreased interleukin-2 levels", "D": "DiGeorge Syndrome", "E": "Decreased phagocytic cell count"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 44-year-old male is brought to the emergency department by fire and rescue after he was the unrestrained driver in a motor vehicle accident. His wife notes that the patient’s only past medical history is recent development of severe episodes of headache accompanied by sweating and palpitations. She says that these episodes were diagnosed as atypical panic attacks by the patient’s primary care provider, and the patient was started on sertraline and alprazolam. In the trauma bay, the patient’s temperature is 97.6°F (36.4°C), blood pressure is 81/56 mmHg, pulse is 127/min, and respirations are 14/min. He has a Glascow Coma Score (GCS) of 10. He is extremely tender to palpation in the abdomen with rebound and guarding. His skin is cool and clammy, and he has thready peripheral pulses. The patient's Focused Assessment with Sonography for Trauma (FAST) exam reveals bleeding in the perisplenic space, and he is taken for emergency laparotomy. He is found to have a ruptured spleen, and his spleen is removed. During manipulation of the bowel, the patient’s temperature is 97.8°F (36.6°C), blood pressure is 246/124 mmHg, and pulse is 104/min. The patient is administered intravenous labetalol, but his blood pressure continues to worsen. The patient dies during the surgery.\n\nWhich of the following medications would most likely have prevented this outcome?", "answer": "Phenoxybenzamine", "options": {"A": "Dantrolene", "B": "Lorazepam", "C": "Phenoxybenzamine", "D": "Propylthiouracil", "E": "Phentolamine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 44-year-old man comes to the emergency department because of a severe headache and blurry vision for the past 3 hours. He has hypertension treated with hydrochlorothiazide. He has missed taking his medication for the past week as he was traveling. He is only oriented to time and person. His temperature is 37.1°C (98.8°F), pulse is 92/min and regular, and blood pressure is 245/115 mm Hg. Cardiopulmonary examination shows no abnormalities. Fundoscopy shows bilateral retinal hemorrhages and exudates. Neurologic examination shows no focal findings. A complete blood count and serum concentrations of electrolytes, glucose, and creatinine are within the reference range. A CT scan of the brain shows no abnormalities. Which of the following is the most appropriate pharmacotherapy?", "answer": "Intravenous nitroprusside", "options": {"A": "Intravenous nitroprusside", "B": "Oral captopril", "C": "Intravenous mannitol", "D": "Oral clonidine", "E": "Sublingual nifedipine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old man is brought to the emergency department by ambulance after falling during a hiking trip. He was hiking with friends when he fell off a 3 story ledge and was not able to be rescued until 6 hours after the accident. On arrival, he is found to have multiple lacerations as well as a pelvic fracture. His past medical history is significant for diabetes and benign prostatic hyperplasia, for which he takes metformin and prazosin respectively. Furthermore, he has a family history of autoimmune diseases. Selected lab results are shown below:\n\nSerum:\nNa+: 135 mEq/L\nCreatinine: 1.5 mg/dL\nBlood urea nitrogen: 37 mg/dL\n\nUrine:\nNa+: 13.5 mEq/L\nCreatinine: 18 mg/dL\nOsmolality: 580 mOsm/kg\n\nWhich of the following is the most likely cause of this patient's increased creatinine level?", "answer": "Blood loss", "options": {"A": "Autoimmune disease", "B": "Blood loss", "C": "Compression of urethra by prostate", "D": "Diabetic nephropathy", "E": "Rhabdomyolysis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the emergency department because of fever, fatigue, and productive cough for 2 days. He had similar symptoms 6 months ago, when he was diagnosed with pneumonia. Three weeks ago, he was diagnosed with otitis media for the sixth time since his birth and was treated with amoxicillin. His temperature is 38.7°C (101.7°F), pulse is 130/min, respirations are 36/min, and blood pressure is 84/40 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 93%. Examination shows purulent discharge in the left ear canal and hypoplastic tonsils without exudate. Coarse crackles are heard over the right lung field on auscultation. An x-ray of the chest shows a right middle lobe consolidation. Flow cytometry shows absent B cells and normal T cells. Which of the following is the most appropriate next step in management?", "answer": "Intravenous immunoglobulins", "options": {"A": "Thymus transplantation", "B": "Stem cell transplantation", "C": "Intravenous immunoglobulins", "D": "Recombinant human granulocyte-colony stimulating factor administration", "E": "Interferon-γ therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old woman presents to the emergency department with dysuria. She denies any hematuria or dyspareunia. Her last menstrual period was 3 weeks ago, and she denies any recent sexual activity. Her temperature is 99.7°F (37.6°F), blood pressure is 127/67 mmHg, pulse is 90/min, and respirations are 17/min. An unusual odor is detected on inspection of the vagina and some gray discharge is noted. Speculum exam reveals a normal cervix and a bimanual exam is unremarkable for adnexal masses or tenderness. What is the next best step in management?", "answer": "Urinalysis, urine culture, KOH prep, and urine pregnancy test", "options": {"A": "Complete blood count (CBC)", "B": "Urinalysis and Pap smear", "C": "Urinalysis, urine culture, and potassium hydoxide prep (KOH)", "D": "Urinalysis, urine culture, KOH prep, and urine pregnancy test", "E": "Urinalysis, KOH prep, and nucleic acid amplification tests for N. gonorrhea and C. trachomatis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old man is brought to the emergency department because of violent jerky movements of his arms and legs that began 30 minutes ago. His father reports that the patient has a history of epilepsy. He is not responsive. Physical examination shows alternating tonic jerks and clonic episodes. There is blood in the mouth. Administration of intravenous lorazepam is begun. In addition, treatment with a second drug is started that alters the flow of sodium ions across neuronal membranes. The second agent administered was most likely which of the following drugs?", "answer": "Fosphenytoin", "options": {"A": "Topiramate", "B": "Fosphenytoin", "C": "Lamotrigine", "D": "Phenobarbital", "E": "Carbamazepine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old girl is brought to the physician because of generalized fatigue and an inability to concentrate in school for the past 4 months. During this period, she has had excessive daytime sleepiness. While going to sleep, she sees cartoon characters playing in her room. She wakes up once or twice every night. While awakening, she feels stiff and cannot move for a couple of minutes. She goes to sleep by 9 pm every night and wakes up at 7 am. She takes two to three 15-minute naps during the day and wakes up feeling refreshed. During the past week while listening to a friend tell a joke, she had an episode in which her head tilted and jaw dropped for a few seconds; it resolved spontaneously. Her father has schizoaffective disorder and her parents are divorced. Vital signs are within normal limits. Physical examination is unremarkable. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Modafinil", "options": {"A": "Modafinil", "B": "Citalopram", "C": "Oral contraceptive pill", "D": "Risperidone", "E": "Venlafaxine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman presents to the emergency department for chest pain and shortness of breath. She was at home making breakfast when her symptoms began. She describes the pain as sharp and located in her chest. She thought she was having a heart attack and began to feel short of breath shortly after. The patient is a college student and recently joined the soccer team. She has no significant past medical history except for a progesterone intrauterine device which she uses for contraception, and a cyst in her breast detected on ultrasound. Last week she returned on a trans-Atlantic flight from Russia. Her temperature is 98.4°F (36.9°C), blood pressure is 137/69 mmHg, pulse is 98/min, respirations are 18/min, and oxygen saturation is 99% on room air. Physical exam reveals an anxious young woman. Cardiac and pulmonary exam are within normal limits. Deep inspiration and palpation of the chest wall elicits pain. Neurologic exam reveals a stable gait and cranial nerves II-XII are grossly intact. Which of the following best describes the most likely underlying etiology?", "answer": "Musculoskeletal inflammation", "options": {"A": "Clot in the pulmonary arteries", "B": "Clot in the pulmonary veins", "C": "Ischemia of the myocardium", "D": "Musculoskeletal inflammation", "E": "Psychogenic etiology"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 26-year-old nursing home staff presents to the emergency room with complaints of palpitations and chest pain for the past 2 days. She was working at the nursing home for the last year but has been trying to get into modeling for the last 6 months and trying hard to lose weight. She is a non-smoker and occasionally drinks alcohol on weekends with friends. On examination, she appears well nourished and is in no distress. The blood pressure is 150/84 mm Hg and the pulse is 118/min. An ECG shows absent P waves. All other physical findings are normal. What is the probable diagnosis?", "answer": "Factitious thyrotoxicosis", "options": {"A": "Factitious thyrotoxicosis", "B": "Anorexia nervosa", "C": "Hashimoto thyroiditis", "D": "Toxic nodular goiter", "E": "Graves' disease"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "You are taking care of a patient with renal failure secondary to anti-fungal therapy. The patient is a 66-year-old male being treated for cryptococcal meningitis. This drug has a variety of known side effects including acute febrile reactions to infusions, anemia, hypokalemia and hypomagnesemia. What is the mechanism of action of of this drug?", "answer": "Pore formation secondary to ergosterol binding", "options": {"A": "Inhibition of 1,3-beta-glucan synthase", "B": "Pore formation secondary to ergosterol binding", "C": "Disruption of microtubule formation", "D": "Inhibition of squalene epoxidase", "E": "Binding of the 50S subunit"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old man presents to the physician for the evaluation of increasing dyspnea and swelling of the lower extremities over the past year. He has no cough. He also complains of frequent awakenings at night and excessive daytime sleepiness. He has no history of a serious illness. He takes no medications other than zolpidem before sleep. He is a 35-pack-year smoker. His blood pressure is 155/95 mm Hg. His BMI is 37 kg/m2. Oropharyngeal examination shows a small orifice and an enlarged tongue and uvula. The soft palate is low-lying. The examination of the nasal cavity shows no septal deviation or polyps. Symmetric pitting edema is seen below the knee, bilaterally. The lungs are clear to auscultation. Echocardiography shows a mildly dilated right ventricle and an elevated systolic pulmonary artery pressure with no abnormalities of the left heart. A ventilation-perfusion scan shows no abnormalities. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Obstructive sleep apnea", "options": {"A": "Chronic obstructive pulmonary disease", "B": "Heart failure with a preserved ejection fraction", "C": "Idiopathic pulmonary artery hypertension", "D": "Obstructive sleep apnea", "E": "Pulmonary thromboembolism"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 43-year-old man comes to the physician for a follow-up examination. Four months ago, he was treated conservatively for ureteric colic. He has noticed during micturition that his urine is reddish-brown initially and then clears by the end of the stream. He has no dysuria. He has hypertension. His only medication is hydrochlorothiazide. He appears healthy and well-nourished. His temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 122/86 mm Hg. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14.1 g/dL\nSerum\nGlucose 88 mg/dL\nCreatinine 0.6 mg/dL\nUrine\nBlood 2+\nProtein negative\nLeukocyte esterase negative\nNitrite negative\nRBCs 5–7/hpf\nWBCs 0–1/hpf\nRBC casts none\nWhich of the following is the most likely origin of this patient's hematuria?\"", "answer": "Urethra", "options": {"A": "Renal glomeruli", "B": "Ureter", "C": "Renal pelvis", "D": "Urethra", "E": "Urinary bladder\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 15-year-old African-American boy is brought to the physician because of left-sided groin pain and difficulty walking for 3 weeks. He reports having pain at rest and increased pain with activity. He recently started playing flag football but does not recall any trauma. He has had many episodes of joint and bone pain that required hospitalization in the past. He is at the 25th percentile for height and 20th percentile for weight. His temperature is 37°C (98.6°F), blood pressure is 120/80 mm Hg, and pulse is 90/min. Examination shows tenderness over the lateral aspect of the hip with no swelling, warmth, or erythema. There is pain with passive internal rotation of the left hip. The remainder of the examination shows no abnormalities. Leukocyte count is 9,000/mm3. Which of the following conditions is the most likely cause of the patient's current symptoms?", "answer": "Avascular necrosis", "options": {"A": "Developmental dysplasia of the hip", "B": "Slipped capital femoral epiphysis", "C": "Stress fracture", "D": "Septic arthritis", "E": "Avascular necrosis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 36-year-old primigravid woman comes to the physician for a prenatal visit at 14 weeks' gestation. She has had episodic headaches over the past month. At home, blood pressure measurements have ranged from 134/82 mm Hg to 148/94 mm Hg. Today, her blood pressure is 146/91 mm Hg. Pelvic examination shows a uterus consistent in size with a 13-week gestation. Serum creatinine is 0.8 mg/dL, serum ALT is 17 U/L, and platelet count is 320,000/mm3. Urinalysis shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Chronic hypertension", "options": {"A": "Chronic hypertension", "B": "Gestational hypertension", "C": "Eclampsia", "D": "Isolated systolic hypertension", "E": "Preeclampsia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman visits the office with complaints of yellowish vaginal discharge and increased urinary frequency for a week. She also complains of pain during urination. Past medical history is irrelevant. She admits to having multiple sexual partners in the past few months. Physical examination is within normal limits except for lower abdominal tenderness. Urine culture yields Chlamydiae trichomatis. What is the most appropriate next step in the management of this patient?", "answer": "Doxycycline", "options": {"A": "Acyclovir", "B": "Doxycycline", "C": "Boric acid", "D": "Clindamycin", "E": "Metronidazole"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old man who is postoperative day 1 after an emergency appendectomy is evaluated by the team managing his care. He complains that he still has not been able to urinate after removal of the urinary catheter that was inserted during surgery. Given this issue, he is started on a medication that acts on a post-synaptic receptor and is resistant to a synaptic esterase. Which of the following is most likely another use of the medication that was administered in this case?", "answer": "Neurogenic ileus", "options": {"A": "Bronchial airway challenge test", "B": "Diagnosis of myasthenia gravis", "C": "Glaucoma management", "D": "Neurogenic ileus", "E": "Pupillary contraction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to his pediatrician by his mother who is worried about his clumsiness. She states that over the past 3 months she has noticed progressive weakness. He used to climb trees and run outside with his cousins, but now he says he gets “too tired.” She’s recently noticed him starting to “walk funny,” despite having “muscular legs.” Upon physical examination, the patient has calf muscle hypertrophy. He uses his arms to rise out of the chair. Labs are obtained that show an elevated creatine kinase. Genetic analysis detects a dystropin gene mutation. A muscle biopsy is performed that reveals reduced dystrophin. Which of the following is the most likely diagnosis?", "answer": "Becker muscular dystrophy", "options": {"A": "Becker muscular dystrophy", "B": "Duchenne muscular dystrophy", "C": "Fragile X syndrome", "D": "Pompe disease", "E": "Spinal muscular atrophy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-month-old male is brought to the emergency room by his mother who reports that the child has a fever. The child was born at 39 weeks of gestation and is at the 15th and 10th percentiles for height and weight, respectively. The child has a history of eczema. Physical examination reveals an erythematous fluctuant mass on the patient’s inner thigh. His temperature is 101.1°F (38.4°C), blood pressure is 125/70 mmHg, pulse is 120/min, and respirations are 22/min. The mass is drained and the child is started on broad-spectrum antibiotics until the culture returns. The physician also orders a flow cytometry reduction of dihydrorhodamine, which is found to abnormal. This patient is at increased risk of infections with which of the following organisms?", "answer": "Aspergillus fumigatus", "options": {"A": "Aspergillus fumigatus", "B": "Enterococcus faecalis", "C": "Giardia lamblia", "D": "Streptococcus pyogenes", "E": "Streptococcus viridans"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old male presents to the emergency department after losing his footing and falling 20 feet off a construction scaffold. He hit his left side on a railing on the way down before landing on his left arm. He denies loss of consciousness during the event or feelings of lightheadedness. He has no significant past medical or surgical history and does not take any regular medications. Evaluation in the trauma bay revealed mild lacerations to the upper and lower extremities, pain to palpation in the distal left forearm, and bruising to the upper left quadrant of the abdomen as well as the lower left thorax. Free fluid was found in the abdomen by ultrasound, fluids were started, and he was rushed to the operating room for an exploratory laparotomy. A heavily lacerated spleen was discovered and removed. No other sources of bleeding were found. Further workup determined he suffered a non-displaced left distal radius fracture and non-displaced 9th and 10th rib fractures. Which of the following should be administered to this patient?", "answer": "Pneumococcal vaccine", "options": {"A": "Pneumococcal vaccine", "B": "Nothing by mouth (NPO)", "C": "Prophylactic ceftriaxone", "D": "Open reduction internal fixation", "E": "Total parenteral nutrition (TPN)"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 53-year-old woman is brought to the physician by her husband for the evaluation of progressive memory loss, which he reports began approximately 2 weeks ago. During this time, she has had problems getting dressed and finding her way back home after running errands. She has also had several episodes of jerky, repetitive, twitching movements that resolved spontaneously. She is oriented only to person and place. She follows commands and speaks fluently. She is unable to read and has difficulty recognizing objects. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Mutant prion accumulation", "options": {"A": "Extracellular senile plaques", "B": "Copper accumulation", "C": "Mutant prion accumulation", "D": "Severe cerebral ischemia", "E": "Increased number of CAG repeats"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-day-old male newborn is brought to the emergency department 1 hour after having a seizure. It lasted approximately 1 minute, and involved blinking and lip-smacking movements as well as left-sided jerking of the hand and foot. His mother says she measured a temperature of 38.2°C (100.7°F) at that time. He has had increasing difficulty feeding since yesterday. He was born at 39 weeks' gestation and weighed 3189 g (7 lb, 1 oz); he currently weighs 2980 g (6 lb, 9 oz). The mother's prenatal course was significant for gonorrhea infection diagnosed early in pregnancy and treated with ceftriaxone and azithromycin combination therapy. The boy appears irritable and lethargic. His temperature is 36.0°C (96.8°F). Examination shows clusters of vesicular lesions with an erythematous base on the patient's face and trunk. There is profuse lacrimation. Laboratory studies show:\nLeukocyte count 16,200/mm3\nSegmented neutrophils 25%\nBands 5%\nLymphocytes 65%\nMonocytes 3%\nEosinophils 2%\nSerum\nGlucose 80 mg/dL\nA lumbar puncture is performed. Cerebrospinal fluid analysis shows a leukocyte count of 117/μL, a protein concentration of 52 mg/dL, and a glucose concentration of 58 mg/dL. Results of blood cultures are pending. Which of the following is the most appropriate pharmacotherapy?\"", "answer": "IV acyclovir", "options": {"A": "IV ganciclovir", "B": "Pyrimethamine", "C": "IV ceftriaxone", "D": "IV acyclovir", "E": "IV vancomycin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 3-day-old boy is brought to the pediatrician for nonpigmented vomiting for the last day. A detailed developmental history reveals that his parents have a nonconsanguineous marriage. He was born by cesarean section at 36 weeks of gestation. His birth weight was 2.6 kg (5.7 lb) and he has been breastfed exclusively. His temperature is 37.0ºC (98.6°F), pulse is 120/min, and respiratory rate is 35/min. On physical examination, a distended abdomen and signs of dehydration are present. On abdominal imaging, a ‘double bubble’ sign and upper intestinal obstruction is present. Abdominal computed tomography shows narrowing of the second part of the duodenum. Barium enema shows normal rotation of the colon. Which of the following is most likely cause of intestinal obstruction in this patient?", "answer": "Annular pancreas", "options": {"A": "Meckel diverticulum", "B": "Annular pancreas", "C": "Leukocyte adhesion deficiency", "D": "Crigler-Najjar type 1", "E": "Intussusception"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 59-year-old female presents to your office with complaints of progressive numbness and tingling in her fingers and toes over the last several months. She also reports \"feeling weak\" in her arms and legs. The patient's past medical history is significant for hypertension and Crohn's disease, which has been well-controlled since undergoing an ileocolectomy 7 years ago. Physical examination is significant for the following findings: decreased sensation to light touch, temperature, and vibration in the bilateral lower extremities; ataxia; positive Romberg sign. Deficiency of which of the following is most likely responsible for this patient's symptoms?", "answer": "Vitamin B12", "options": {"A": "Vitamin B1", "B": "Vitamin B2", "C": "Vitamin B3", "D": "Vitamin B6", "E": "Vitamin B12"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-year-old man presents to his physician with a complaint of pain with urination that has developed and persisted over the past 8 days. Upon awakening today, he also noted a clear discharge from his urethra. The patient states he is otherwise healthy. Social history is notable for the patient working at a local farm with livestock. Review of systems is notable for left knee and ankle pain for the past week and worsening of his seasonal allergies with red and itchy eyes. His temperature is 97.7°F (36.5°C), blood pressure is 122/83 mmHg, pulse is 89/min, respirations are 14/min, and oxygen saturation is 98% on room air. Which of the following is likely to be positive in this patient?", "answer": "HLA-B27", "options": {"A": "Anti-CCP", "B": "Anti-dsDNA", "C": "HLA-B27", "D": "HLA-DR4", "E": "p-ANCA"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 50-year-old woman with a history of schizophrenia is being admitted to a locked inpatient psychiatry unit after discontinuing her medication. She was found wandering the streets, screaming in the air. According to her medical records, she was diagnosed with schizophrenia in her early 20s. She was initially living with her family but because of issues with medication compliance, substance abuse, and interpersonal problems, she has been homeless for the past 10 years. In addition to schizophrenia, her complicated medical history includes hypertension, diabetes, hypothyroidism, hyperlipidemia, morbid obesity, and substance abuse. She is not taking any medications at this time. At the hospital, her heart rate is 90/min, respiratory rate is 17/min, blood pressure is 110/65 mm Hg, and temperature is 37.0°C (98.6°F). She appears nervous and dirty. The clothes she was wearing are tattered and smell of urine and feces. She is too agitated and disruptive to perform a proper physical exam. Which of the following medications would be the most appropriate treatment for schizophrenia in this patient?", "answer": "Haloperidol", "options": {"A": "Clozapine", "B": "Olanzapine", "C": "Quetiapine", "D": "Haloperidol", "E": "Risperidone"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old sexually active, otherwise healthy female presents to her primary care physician complaining of several days of dysuria, frequency, urgency, and suprapubic pain. She denies fever, flank pain, vaginal itching, or vaginal bleeding/discharge. Which organism is most likely responsible for this patient's symptoms?", "answer": "Escherichia coli", "options": {"A": "Staphylococcus saprophyticus", "B": "Chlamydia trachomatis", "C": "Proteus mirabilis", "D": "Klebsiella pneumoniae", "E": "Escherichia coli"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old IV drug user comes into the emergency department after four days of pain in his right ankle. The patient is lethargic and unable to answer any questions about his medical history. His vitals are HR 110, T 101.5, RR 20, BP 100/60. His physical exam is notable for track marks in his toes and his right ankle is erythematous and swollen. Moving any part of the right foot creates a 10/10 pain. A radiograph revels no evidence of fractures. A Gram stain of the joint fluid aspirate demonstrates purple cocci in clusters. The fluid is yellow, opaque, with more than 70,000 cells/mm^3 (80% neutrophils). What is the most likely diagnosis?", "answer": "Staphylococcus infectious arthritis", "options": {"A": "Monosodium urate crystal formation", "B": "Salmonella infectious arthritis", "C": "Staphylococcus infectious arthritis", "D": "Borrelia infectious arthritis", "E": "Osteoarthritis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman presents with abdominal pain. She says that she has been experiencing a mild ‘tummy ache’ for about a week. On further questioning, the physician finds that she has been struggling to cope with her daily activities for the past month. She says that she is sad on most days of the week and doesn’t have much motivation to get up and do anything. She has difficulty concentrating and focusing on her job and, on many occasions, doesn’t have the urge to wake up and go to work. She has observed that on certain days she sleeps for 10-12 hours. She attributes this to the heaviness she feels in her legs which make it very difficult for her to get out of bed. Lately, she has also noticed that she is eating more than usual. Which of the following would most likely be another characteristic of this patient’s condition?", "answer": "Inability to participate in social events she is invited to", "options": {"A": "Inability to participate in social events she is invited to", "B": "A belief that people are secretly out to sabotage her", "C": "An increased frequency of symptoms during winter", "D": "Guilt related to the way she treats others", "E": "Spells of deranged excitement"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-month-old boy is brought to the emergency department 25 minutes after having a seizure. He has had multiple seizures during the past week. His mother has noticed that he has become lethargic and has had a weak cry for the past month. He was born at 37 weeks' gestation. He is at the 20th percentile for height and 15th percentile for weight. His temperature is 36.7°C (98°F), respirations are 50/min, and pulse is 140/min. Examination shows a soft and nontender abdomen. The liver is palpated 4 cm below the right costal margin; there is no splenomegaly. Serum studies show:\nNa+ 137 mEq/L\nCl- 103 mEq/L\nK+ 3.9 mEq/L\nGlucose 32 mg/dL\nCalcium 9.6 mg/dL\nTotal cholesterol 202 mg/dL\nTriglycerides 260 mg/dL\nLactate 4.2 mEq/L (N = 0.5 - 2.2 mEq/L)\nA deficiency of which of the following enzymes is the most likely cause of this infant's symptoms?\"", "answer": "Glucose 6-phosphatase", "options": {"A": "Glycogen branching enzyme", "B": "Galactose 1-phosphate uridyltransferase", "C": "Fructokinase", "D": "Glucose 6-phosphatase", "E": "Acid maltase\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old gentleman with severe COPD is found to have a respiratory quotient of 0.8. His physician would like to decrease the amount of CO2 produced by the patient's metabolism, thereby reducing the energy breathing expenditure required to eliminate the patient's CO2 respiratory burden. Which of the following dietary modifications would decrease this patient's respiratory quotient?", "answer": "Decreasing carbohydrate intake, increasing fat intake", "options": {"A": "Increasing carbohydrate intake, decreasing fat intake", "B": "Increasing carbohydrate intake, decreasing protein intake", "C": "Decreasing carbohydrate intake, increasing fat intake", "D": "Decreasing carbohydrate intake, increasing protein intake", "E": "Decreasing fat intake, increasing protein intake"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 61-year-old man presents to the family medicine clinic with a worsening cough for the last week. He denies hemoptysis, sputum production, shortness of breath, or upper respiratory tract symptoms. He does endorse nausea and heartburn after he eats large meals, as well as an occasional metallic taste in his mouth throughout the day. He has been diagnosed with hypertension and osteoarthritis, for which he takes lisinopril and aspirin. He has smoked half a pack of cigarettes per day since he was 20 years old. Three years ago, he had his second colonoscopy performed with normal results. His heart rate is 76/min, respiratory rate is 16/min, temperature is 37.3°C (99.2°F), and blood pressure is 148/92 mm Hg. He exhibits signs of truncal obesity. Heart auscultation reveals wide splitting of S2. Auscultation of the lungs is clear, but wheezing is noted on forced expiration. Which of the following is recommended for the patient at this time?", "answer": "Zoster vaccine", "options": {"A": "Low-dose chest CT", "B": "Intra-articular steroid injection", "C": "Zoster vaccine", "D": "Hepatitis B vaccine", "E": "Meningococcal vaccine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 62-year-old man, a retired oil pipeline engineer, presents to his primary care physician with complaints of headaches, fatigue, and constant ringing in his ears. Recurrently he has developed pruritus, usually after a hot shower. He also noted a constant burning sensation in his fingers and toes, independent of physical activity. On examination, he has a red face and his blood pressure levels are 147/89 mm Hg. A CBC revealed that his Hb is 19.0 g/dL and Hct is 59%. Because of his condition, his physician prescribes him 81 mg of aspirin to be taken daily in addition to therapeutic phlebotomy. Which of the statements below is true about this patient’s condition?", "answer": "Mutation of the JAK2 gene is commonly seen in this condition.", "options": {"A": "Arterial oxygen saturation is usually higher than normal values in this condition.", "B": "Mutation of the JAK2 gene is commonly seen in this condition.", "C": "The patient has a decreased risk of developing myelofibrosis.", "D": "Serum erythropoietin is expected to be high.", "E": "Warfarin and phlebotomy are the preferred course of treatment."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old man presents with yellowing of the eyes. He says symptoms onset acutely 3 days ago and have not improved. He says he has had similar episodes for the past 10 years. Each episode is self-limited, lasting no more than 3–5 days. The patient denies any recent history of nausea, weight loss, abdominal pain, light-colored stools, dark urine, or pruritus. Current medications are herbal supplements and a multivitamin. The patient is afebrile and vital signs are within normal limits. His BMI is 32 kg/m2. Physical exam is unremarkable. Laboratory findings are significant for the following:\nTotal bilirubin 3 mg/dL\nDirect bilirubin 0.2 mg/dL\nAST/ALT/Alkaline phosphatase Normal\nHematocrit/lactate dehydrogenase (LDH)/haptoglobin Normal\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Gilbert’s syndrome", "options": {"A": "Medication-induced hemolysis", "B": "Crigler-Najjar syndrome type 1", "C": "Dubin-Johnson syndrome", "D": "Cholelithiasis", "E": "Gilbert’s syndrome"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 75-year-old woman with hypertension presents to your office for a routine health exam. Her medications include hydrochlorothiazide and a multivitamin. She has been feeling well; however, she mentions that her family has been complaining about the volume of the television. She also reports difficulty hearing when others have called her name. On physical examination, her temperature is 99°F (37.2°C), blood pressure is 120/85 mmHg, pulse is 70/min, respirations are 17/min, and pulse oximetry is 99% on room air. The tympanic membrane is gray with no drainage or granulation tissue. Audiometry is consistent with high frequency sensorineural hearing loss. Which of the following is the most likely physiology behind this patient’s presentation?", "answer": "Destruction of cochlear hair cells", "options": {"A": "Increased endolymph production", "B": "Destruction of cochlear hair cells", "C": "Bacterial infection of the middle ear", "D": "Abnormal skin growth in the middle ear", "E": "Fixation of the stapes to the cochlea"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old woman presents to the dermatologist with concern for a new skin lesion (Image A). You note two similar lesions on her back. Which of the following is a true statement about these lesions?", "answer": "They will likely increase in number over time.", "options": {"A": "They will likely grow rapidly.", "B": "They will likely regress spontaneously.", "C": "They may be associated with von Hippel-Lindau disease.", "D": "They will likely increase in number over time.", "E": "They must be followed closely for concern of malignancy."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old man comes to the physician because of a 3-month history of upper abdominal pain and nausea that occurs about 3 hours after eating and at night. These symptoms improve with eating. After eating, he often has a feeling of fullness and bloating. He has had several episodes of dark stools over the past month. He has smoked one pack of cigarettes daily for 40 years and drinks 2 alcoholic beverages daily. He takes no medications. His temperature is 36.4°C (97.5°F), pulse is 80/min, and blood pressure is 110/70 mm Hg. Abdominal examination shows epigastric tenderness with no guarding or rebound. Bowel sounds are normal. Which of the following treatments is most appropriate to prevent further complications of the disease in this patient?", "answer": "Amoxicillin, clarithromycin, and omeprazole", "options": {"A": "Truncal vagotomy", "B": "Amoxicillin, clarithromycin, and omeprazole", "C": "Fundoplication, hiatoplasty, and gastropexy", "D": "Distal gastrectomy with gastroduodenostomy", "E": "Intravenous vitamin B12 supplementation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old woman comes to the physician because of a 12-week history of persistent cough. The cough is nonproductive and worse at night. She otherwise feels well. She has not had any changes in appetite or exercise tolerance. For the past year, she has smoked an occasional cigarette at social occasions. Use of herbal cough medications has not provided any symptom relief. She has no history of serious illness but reports getting a runny nose every morning during winter. Her temperature is 37°C (98.6°F), pulse is 68/min, respirations are 12/min, and blood pressure is 110/76 mm Hg. Cardiopulmonary examination and an x-ray of the chest show no abnormalities. Her FEV1 is normal. Which of the following is the most appropriate next step in management?", "answer": "Oral diphenhydramine", "options": {"A": "Prednisone therapy", "B": "Oral amoxicillin-clavulanate", "C": "Codeine syrup", "D": "Oral acetylcysteine", "E": "Oral diphenhydramine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 51-year-old man comes to the physician because of progressively worsening dyspnea on exertion and fatigue for the past 2 months. Cardiac examination shows no murmurs or bruits. Coarse crackles are heard at the lung bases bilaterally. An ECG shows an irregularly irregular rhythm with absent p waves. An x-ray of the chest shows globular enlargement of the cardiac shadow with prominent hila and bilateral fluffy infiltrates. Transthoracic echocardiography shows a dilated left ventricle with an ejection fraction of 40%. Which of the following is the most likely cause of this patient's condition?", "answer": "Chronic supraventricular tachycardia", "options": {"A": "Uncontrolled essential hypertension", "B": "Chronic supraventricular tachycardia", "C": "Deposition of misfolded proteins", "D": "Inherited β-myosin heavy chain mutation", "E": "Acute psychological stress"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old female presents to her gynecologist with bloating, abdominal discomfort, and fatigue. She has a history of hypertension and takes hydrochlorothiazide. Physical exam reveals ascites and right adnexal tenderness. Initial imaging reveals a mass in the right ovary and eventual biopsy of the mass reveals ovarian serous cystadenocarcinoma. She is started on a chemotherapeutic agent with plans for surgical resection. Soon after starting the medication, she develops dysuria and hematuria. Laboratory analysis of her urine is notable for the presence of a cytotoxic metabolite. Which of the following mechanisms of action is consistent with the medication in question?", "answer": "DNA alkylating agent", "options": {"A": "DNA alkylating agent", "B": "Platinum-based DNA intercalator", "C": "Microtubule inhibitor", "D": "Folate analog", "E": "BRAF inhibitor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old man is running a marathon. Upon reaching the finish line, his serum lactate levels were measured and were significantly increased as compared to his baseline. Which of the following pathways converts the lactate produced by muscles into glucose and transports it back to the muscles?", "answer": "Cori cycle", "options": {"A": "Glycogenesis", "B": "Citric acid cycle", "C": "Glycolysis", "D": "Cori cycle", "E": "Pentose phosphate pathway"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old man is admitted to the hospital for pain and swelling in his right foot. His temperature is 39.7°C (103.5°F), pulse is 116/min, respirations are 23/min, and blood pressure is 69/39 mmHg. A drug is administered via a peripheral intravenous line that works primarily by increasing inositol trisphosphate concentrations in arteriolar smooth muscle cells. Eight hours later, the patient has pain at the right antecubital fossa. Examination shows the skin around the intravenous line site to be pale and cool to touch. After discontinuing the infusion, which of the following is the most appropriate pharmacotherapy to prevent further tissue injury in this patient?", "answer": "Phentolamine", "options": {"A": "Procaine", "B": "Phentolamine", "C": "Tamsulosin", "D": "Conivaptan", "E": "Heparin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old man comes to the physician for the evaluation of episodic headaches involving both temples for 5 months. The patient has been taking acetaminophen, but it has not provided relief. He has also had double vision. Ophthalmic examination shows impaired peripheral vision bilaterally. Contrast MRI of the head shows a 14 x 10 x 8-mm intrasellar mass. Further evaluation is most likely to show which of the following findings?", "answer": "Impotence", "options": {"A": "Macroglossia", "B": "Impotence", "C": "Galactorrhea", "D": "Polyuria", "E": "Diarrhea"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 44-year-old G2P2 African American woman presents to her gynecologist for dysmenorrhea. She reports that for the past few months, she has been having severe pain during her menses. She also endorses menstrual bleeding that has been heavier than usual. The patient reports that her cycles are regular and occur every 30 days, and she denies both dyspareunia and spotting between her periods. Her last menstrual period was two weeks ago. In terms of her obstetric history, the patient had two uncomplicated pregnancies, and she had no difficulty becoming pregnant. She has never had an abnormal pap smear. Her past medical history is otherwise significant for hyperlipidemia and asthma. On physical exam, the patient’s uterus is tender, soft, and enlarged to the size of a pregnant uterus at 10 weeks of gestation. She is non-tender during vaginal exam, without cervical motion tenderness or adnexal masses. Her BMI is 24 kg/m2. A urine pregnancy test is negative.\n\nWhich of the following is the most likely diagnosis for this patient?", "answer": "Presence of endometrial glands and stroma in uterine myometrium", "options": {"A": "Hyperplastic overgrowths of endometrial glands and stroma", "B": "Malignant invasion of endometrial cells into uterine myometrium", "C": "Presence of endometrial glands and stroma in uterine myometrium", "D": "Presence of endometrial glands and stroma outside the uterus", "E": "Benign smooth muscle tumor of the uterus"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman is brought to the emergency department by her friend because of strange behavior. Two hours ago, she was at a night club where she got involved in a fight with the bartender. Her friend says that she was smoking a cigarette before she became irritable and combative. She repeatedly asked “Why are you pouring blood in my drink?” before hitting the bartender. She has no history of psychiatric illness. Her temperature is 38°C (100.4°F), pulse is 100/min, respirations are 19/min, and blood pressure is 158/95 mm Hg. Examination shows muscle rigidity. She has a reduced degree of facial expression. She has no recollection of her confrontation with the bartender. Which of the following is the most likely primary mechanism responsible for this patient's symptoms?", "answer": "Inhibition of NMDA receptors", "options": {"A": "Inhibition of dopamine D2 receptors", "B": "Stimulation of cannabinoid receptors", "C": "Stimulation of 5HT2A and dopamine D2 receptors", "D": "Inhibition of norepinephrine, serotonin, and dopamine reuptake", "E": "Inhibition of NMDA receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 50-year-old overweight woman presents to her physician with complaints of recurrent episodes of right upper abdominal discomfort and cramping. She says that the pain is mild and occasionally brought on by the ingestion of fatty foods. The pain radiates to the right shoulder and around to the back, and it is accompanied by nausea and occasional vomiting. She admits to having these episodes over the past several years. Her temperature is 37°C (98.6° F), respiratory rate is 15/min, pulse is 67/min, and blood pressure is 122/98 mm Hg. Her physical examination is unremarkable. Lab reports reveal:\nHb%   13 gm/dL\nTotal count (WBC):   11,000/mm3\nDifferential count:    \n  Neutrophils: 70%\n  Lymphocytes: 25%\n  Monocytes: 5%\nESR:   10 mm/hr\nSerum:    \n  Albumin: 4.2 gm/dL\n  Alkaline phosphatase: 150 U/L\n  Alanine aminotransferase: 76 U/L\n  Aspartate aminotransferase: 88 U/L\nWhat is the most likely diagnosis?", "answer": "Choledocholithiasis", "options": {"A": "Acute cholecystitis", "B": "Choledocholithiasis", "C": "Pancreatitis", "D": "Duodenal peptic ulcer", "E": "Gallbladder cancer"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2400-g (5.29-lb) male newborn is delivered at term to a 38-year-old woman. The initial examination shows that the child is at the 5th percentile for head circumference and 10th percentile for weight and length. He has a sloping forehead, a flat nasal bridge, increased interocular distance, low-set ears, and a protruding tongue. An examination of the peripheries reveals a single palmar crease and an increased gap between the first and second toe. Ocular examination reveals small white and brown spots in the periphery of both irises. The abdomen is distended. An x-ray of the abdomen shows two large air-filled spaces in the upper quadrant. This child's condition is most likely associated with which of the following cardiac anomalies?", "answer": "Atrioventricular septal defect", "options": {"A": "Atrioventricular septal defect", "B": "Ventricular septal defect", "C": "Tetralogy of Fallot", "D": "Pulmonary valve stenosis", "E": "Transposition of the great arteries\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-month-old boy is brought the pediatrician for immunizations and assessment. His parents report that he is eating well and produces several wet diapers every day. He is occasionally fussy, but overall a happy and curious child. The boy was born at 39 weeks gestation via spontaneous vaginal delivery On physical examination his vital signs are stable. His weight and height are above the 85th percentile for his age and sex. On chest auscultation, the pediatrician detects a loud harsh holosystolic murmur over the left lower sternal border. The first and second heart sounds are normal. An echocardiogram confirms the diagnosis of the muscular ventricular septal defect without pulmonary hypertension. Which of the following is the best management strategy for this patient?", "answer": "Reassurance of the parents and regular follow-up", "options": {"A": "Reassurance of the parents and regular follow-up", "B": "Antibiotic prophylaxis against infective endocarditis", "C": "Oral digoxin and regular follow-up", "D": "Surgical closure of the defect using cardiopulmonary bypass", "E": "Transcatheter occlusion closure of the defect"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 49-year-old male presents to the emergency room with dyspnea and pulmonary edema. He reports that he has been smoking 2 packs a day for the past 25 years and has difficulty breathing during any sustained physical activity. His blood pressure is normal, and he reports a history of COPD. An echocardiogram was ordered as part of a cardiac workup. Which of the following would be the most likely finding?", "answer": "Coronary sinus dilation", "options": {"A": "Aortic stenosis", "B": "Mitral valve insufficiency", "C": "Left ventricular hypertrophy", "D": "Coronary sinus dilation", "E": "Tricuspid valve stenosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman comes to the physician because of an 8-month history of weakness and intermittent burning pain in her neck, shoulders, and arms. She was involved in a motor vehicle collision 1 year ago. Examination of the upper extremities shows absent reflexes, muscle weakness, and fasciculations bilaterally. Sensation to temperature and pain is absent; vibration and proprioception are preserved. The pupils are equal and reactive to light. Which of the following is the most likely diagnosis?", "answer": "Syringomyelia", "options": {"A": "Tabes dorsalis", "B": "Syringomyelia", "C": "Subacute combined degeneration", "D": "Amytrophic lateral sclerosis", "E": "Cervical disk prolapse"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 43-year-old man presents to his primary care provider with concerns about general weakness and decreased concentration over the past several months. He reports constipation and unintentional weight loss of about 9.1 kg (20 lb). The past medical symptoms are noncontributory. He works as a bank manager and occasionally drinks alcohol but does not smoke tobacco. Today, the vital signs include blood pressure 145/90 mm Hg, heart rate 60/min, respiratory rate 19/min, and temperature 36.6°C (97.9°F). On physical examination, the patient looks fatigued. His heart has a regular rate and rhythm, and his lungs are clear to auscultation bilaterally. Laboratory studies show:\nCalcium 14.5 mg/dL  \nPhosphate 2.2 mg/dL  \nParathyroid hormone (PTH)  18 pg/mL  \nParathyroid hormone-related protein (PTHrP) 4 pmol/L Normal value: < 2 pmol/L\nCalcitriol 46 pg/mL Normal value: 25–65 pg/mL\nT3 120 ng/mL  \nT4 10.2 mcg/dL  \nTaking into account the clinical and laboratory findings, what is the most likely cause of this patient’s hypercalcemia?", "answer": "Malignancy", "options": {"A": "Chronic kidney disease", "B": "Hyperparathyroidism", "C": "Hypervitaminosis D", "D": "Malignancy", "E": "Thyrotoxicosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 61-year-old woman who recently emigrated from India comes to the physician because of a 2-month history of fever, fatigue, night sweats, and a productive cough. She has had a 5-kg (11-lb) weight loss during this period. She has a history of type 2 diabetes mellitus and poorly controlled asthma. She has had multiple asthma exacerbations in the past year that were treated with glucocorticoids. An x-ray of the chest shows a cavitary lesion of the posterior apical segment of the left upper lobe with consolidation of the surrounding parenchyma. The pathogen identified on sputum culture is found to be resistant to multiple drugs, including streptomycin. Which of the following mechanisms is most likely involved in bacterial resistance to this drug?", "answer": "Alteration in 30S ribosomal subunit", "options": {"A": "Alteration in the sequence of gyrA genes", "B": "Inhibition of bacterial synthesis of RNA", "C": "Alteration in 30S ribosomal subunit", "D": "Upregulation of mycolic acid synthesis", "E": "Upregulation of arabinosyl transferase production"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old woman comes to the physician because of a 3-month history of intermittent severe left neck, shoulder, and arm pain and paresthesias of the left hand. The pain radiates to the radial aspect of her left forearm, thumb, and index finger. She first noticed her symptoms after helping a friend set up a canopy tent. There is no family history of serious illness. She appears healthy. Vital signs are within normal limits. When the patient extends and rotates her head to the left and downward pressure is applied, she reports paresthesias along the radial aspect of her left forearm and thumb. There is weakness when extending the left wrist against resistance. The brachioradialis reflex is 1+ on the left and 2+ on the right. The radial pulse is palpable bilaterally. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "C5-C6 disc herniation\n\"", "options": {"A": "Carpal tunnel syndrome", "B": "Syringomyelia", "C": "Thoracic outlet syndrome", "D": "Amyotrophic lateral sclerosis", "E": "C5-C6 disc herniation\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 38-year-old male is admitted to the hospital after a motor vehicle accident in which he sustained a right diaphyseal femur fracture. His medical history is significant for untreated hypertension. He reports smoking 1 pack of cigarettes per day and drinking 1 liter of bourbon daily. On hospital day 1, he undergoes open reduction internal fixation of his fracture with a femoral intramedullary nail. At what time after the patient's last drink is he at greatest risk for suffering from life-threatening effects of alcohol withdrawal?", "answer": "48-72 hours", "options": {"A": "Less than 24 hours", "B": "24-48 hours", "C": "48-72 hours", "D": "5-6 days", "E": "1 week"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 54-year-old male comes to the clinic to initiate care with a new physician. He has no complaints at this time. When taking his history, the patient says his medical history is notable for diabetes and hypertension both of which are well managed on his medications. His medications are metformin and lisinopril. A review of systems is negative. While taking the social history, the patient hesitates when asked about alcohol consumption. Further gentle questioning by the physician leads the patient to admit that he drinks 5-6 beers per night and up to 10-12 drinks per day over the weekend. He says that he has been drinking like this for “years.” He becomes emotional and says that his alcohol is negatively affecting his relationship with his wife and children; however, when asked about efforts to decrease his consumption, the patient says he has not tried in the past and doesn’t think he has “the strength to stop”. Which of the following stages of change most accurately describes this patient’s behavior?", "answer": "Contemplation", "options": {"A": "Precontemplation", "B": "Contemplation", "C": "Preparation", "D": "Action", "E": "Maintenance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old man comes to the physician because of a 2-month history of severe chest discomfort. The chest discomfort usually occurs after heavy meals or eating in the late evening and lasts several hours. He has nausea sometimes but no vomiting. He has also had an occasional nighttime cough during this period. He has hypertension and type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for the past 41 years and drinks one beer daily. Current medications include metformin, naproxen, enalapril,and sitagliptin. He is 177 cm (5 ft 10 in) tall and weighs 135 kg (297 lb); BMI is 43 kg/m2. Vital signs are within normal limits. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. Laboratory studies are within the reference ranges. An ECG shows no abnormalities. An upper endoscopy shows that the Z-line is located 4 cm above the diaphragmatic hiatus and reveals the presence of a 1.5-cm esophageal ulcer with an erythematous base and without bleeding. The physician recommends weight loss as well as smoking and alcohol cessation. Treatment with omeprazole is begun. One month later, his symptoms are unchanged. Which of the following is the most appropriate next step in management?", "answer": "Laparoscopic Nissen fundoplication with hiatoplasty", "options": {"A": "Clarithromycin, amoxicillin, and omeprazole therapy for 2 weeks", "B": "Laparoscopic herniotomy", "C": "Laparoscopic Nissen fundoplication with hiatoplasty", "D": "Calcium carbonate therapy for 2 months", "E": "Bariatric surgery"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old man presents to his primary care physician because he has been experiencing episodes where he wakes up at night gasping for breath. His past medical history is significant for morbid obesity as well as hypertension for which he takes lisinopril. He is diagnosed with sleep apnea and prescribed a continuous positive airway pressure apparatus. In addition, the physician discusses making lifestyle and behavioral changes such as dietary modifications and exercise. The patient agrees to attempt these behavioral changes. Which of the following is most likely to result in improving patient adherence to this plan?", "answer": "Provide follow-up appointments to assess progress in attaining goals", "options": {"A": "Ask the patient to bring a family member to next appointment", "B": "Inform the patient of the health consequences of not intervening", "C": "Provide appropriate publications for the patient's educational level", "D": "Provide follow-up appointments to assess progress in attaining goals", "E": "Refer the patient to a peer support group addressing lifestyle changes"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 12-year-old boy presents to the emergency room with difficulty breathing after several days of severe sore throat. Further history reveals that his family immigrated recently from Eastern Europe and he has never previously seen a doctor. Physical exam shows cervical lymphadenopathy with extensive neck edema as well as the finding shown in the image provided. You suspect a bacteria that causes the disease by producing an AB type exotoxin. Which of the following is the proper medium to culture the most likely cause of this infection?", "answer": "Tellurite Agar", "options": {"A": "Bordet-Genou Agar", "B": "Charcoal Yeast Agar", "C": "Eaton's Agar", "D": "Tellurite Agar", "E": "Thayer-Martin Agar"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman with β-thalassemia major comes to the physician with a 1-week history of fatigue. She receives approximately 8 blood transfusions per year; her last transfusion was 1 month ago. Examination shows conjunctival pallor. Her hemoglobin level is 6.5 mg/dL. Microscopic evaluation of a liver biopsy specimen in this patient would most likely show which of the following?", "answer": "Macrophages with cytoplasmic granules that stain golden-yellow with hematoxylin", "options": {"A": "Macrophages with yellow-brown, lipid-containing granules", "B": "Macrophages with cytoplasmic granules that stain golden-yellow with hematoxylin", "C": "Extracellular deposition of pink-staining proteins", "D": "Cytoplasmic brown-pigmented granules that stain positive for S-100", "E": "Cytoplasmic pink-staining granules that stain positive with PAS"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Myeloperoxidase (MPO) is a heme-containing molecule that is found in the azurophilic granules of neutrophils. Upon release, the enzyme catalyzes hypochlorous acid production during the phagocytic response. In the setting of pneumonia, which of the following is the end result and clinical significance of this reaction?", "answer": "Green color of sputum", "options": {"A": "Green color of sputum", "B": "Cough", "C": "Rust-tinged sputum", "D": "Fever", "E": "Shortness of breath"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 11-year-old male is brought in by ambulance to the emergency department after being a restrained passenger in a motor vehicle accident. His father was driving him to soccer practice when they were hit by a wrong way driver. On presentation, his temperature is 101°F (38.3°C), blood pressure is 100/62 mmHg, pulse is 108/min, and respirations are 21/min. He is found to be agitated and complains of nausea, severe epigastric pain, and lower extremity pain. Physical exam reveals lacerations and ecchymosis on his left forehead, right flank, and lower extremities. Radiographs demonstrate an open book fracture of the pelvis as well as bilateral femur fractures. Despite multiple interventions, his condition deteriorates and he passes away from his injuries. Post-mortem pathologic examination of abdominal tissues reveals white deposits containing calcium. Abnormal activity of which of the following proteins is most likely responsible for these deposits?", "answer": "Lipases", "options": {"A": "Immunoglobulin", "B": "Lipases", "C": "Plasmin", "D": "Proteases", "E": "Thrombin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old homeless man presents to the emergency department with an altered mental status. He is not answering questions. His past medical history is unknown. A venous blood gas is drawn demonstrating the following.\n\nVenous blood gas\npH: 7.2\nPaO2: 80 mmHg\nPaCO2: 80 mmHg\nHCO3-: 24 mEq/L\n\nWhich of the following is the most likely etiology of this patient's presentation?", "answer": "Heroin overdose", "options": {"A": "Aspirin overdose", "B": "COPD", "C": "Diabetic ketoacidosis", "D": "Ethylene glycol intoxication", "E": "Heroin overdose"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 5-year-old girl is brought to the physician by her mother because of a 1-month history of a painful ulcer on her face. She has developed painful sunburns in the past with minimal UV exposure. Examination of the skin shows a 2-cm ulcerated nodule on the left cheek. There are scaly, hyperpigmented papules and plaques over the skin of the entire body. Ophthalmologic examination shows decreased visual acuity, clouded corneas, and limbal injection. Examination of a biopsy specimen from the facial lesion shows poorly-differentiated squamous cell carcinoma. Impairment of which of the following proteins is the most likely cause of this patient's condition?", "answer": "Excision endonuclease", "options": {"A": "Excision endonuclease", "B": "Rb nuclear protein", "C": "Base-specific glycosylase", "D": "DNA helicase", "E": "ATM serine/threonine kinase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old woman is brought to the physician by her son for an evaluation of cognitive decline. Her son reports that she has had increased difficulty finding her way back home for the last several months, despite having lived in the same city for 40 years. He also reports that his mother has been unable to recall the names of her relatives and been increasingly forgetting important family gatherings such as her grandchildren's birthdays over the last few years. The patient has hypertension and type 2 diabetes mellitus. She does not smoke or drink alcohol. Her current medications include enalapril and metformin. Her temperature is 37°C (98.6°F), pulse is 70/min, and blood pressure is 140/80 mm Hg. She is confused and oriented only to person and place. She recalls 2 out of 3 words immediately and 1 out of 3 after 5 minutes. Her gait and muscle strength are normal. Deep tendon reflexes are 2+ bilaterally. The remainder of the examination shows no abnormalities. Further evaluation is most likely to reveal which of the following findings?", "answer": "Generalized cerebral atrophy", "options": {"A": "Hallucinations", "B": "Resting tremor", "C": "Generalized cerebral atrophy", "D": "Urinary incontinence", "E": "Myoclonic movements\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 20-year-old man is brought to the behavioral health clinic by his roommate. The patient’s roommate says that the patient has been looking for cameras that aliens planted in their apartment for the past 2 weeks. Approximately 3 months prior to the onset of this episode, the roommate says the patient stopped playing basketball daily because the sport no longer interested him. He stayed in his bedroom most of the day and was often tearful. The roommate recalls the patient talking about death frequently. The patient states he has been skipping many meals and has lost a significant amount of weight as a result. At the time his delusions about the aliens began, the depressive-related symptoms were no longer present. He has no other medical conditions. He does not drink but smokes 2 packs of cigarettes daily for the past 5 years. His vitals include: blood pressure 130/88 mm Hg, pulse 92/min, respiratory rate 16/min, temperature 37.3°C (99.1°F). On physical examination, the patient seems apathetic and uses an obscure word that appears to be ‘chinterfittle’. His affect is flat throughout the entire interaction. He is experiencing bizarre delusions but no hallucinations. The patient does not express suicidal or homicidal ideations. Urine drug screen results are provided below:\nAmphetamine negative\nBenzodiazepine negative\nCocaine negative\nGHB negative\nKetamine negative\nLSD negative\nMarijuana positive\nOpioids negative\nPCP negative\nWhich of the following is the correct diagnosis?", "answer": "Schizoaffective disorder", "options": {"A": "Schizophrenia with depression", "B": "Schizoaffective disorder", "C": "Depression with psychotic features", "D": "Cannabis intoxication", "E": "Brief psychotic disorder"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman presents with diplopia. She says that she has been experiencing drooping of her eyelids and severe muscle weakness. She reports that her symptoms are worse at the end of the day. Which of the following additional findings would most likely be seen in this patient?", "answer": "Increased acetylcholine receptor antibody", "options": {"A": "Increased antinuclear antibodies", "B": "Increased acetylcholine receptor antibody", "C": "Increased calcium channel receptor antibodies", "D": "Increased serum creatine kinase levels", "E": "Albuminocytological dissociation in the cerebrospinal fluid"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old man presents to the primary care clinic to establish care. He has not seen a physician for many years. He has no complaints or concerns but, on further questioning, does have some vague abdominal discomfort. He has no known past medical history and takes no medications. His social history is notable for injecting heroin throughout his late-teens and 20s, but he has been clean and sober for over a decade. At the clinic, the vital signs include: heart rate 90/min, respiratory rate 17/min, blood pressure 110/65 mm Hg, and temperature 37.0°C (98.6°F). The physical exam shows a slightly distended abdomen. The laboratory studies are notable for a platelet count of 77,000/uL and an international normalized ratio (INR) of 1.7. Which of the following is the next best step in the diagnosis of this patient?", "answer": "Hepatitis C antibody", "options": {"A": "Anti-nuclear antibody test", "B": "Bone marrow biopsy", "C": "Hepatitis C antibody", "D": "HIV ELISA", "E": "Platelet aggregation assay"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 8-year-old boy presents with a limp favoring his right leg. The patient’s mother noticed he had been limping without complaint for the past 6 months. Past medical history is significant for the flu last year. No current medications. All immunizations are up to date. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 100/60 mm Hg, pulse 74/min, respiratory rate 19/min, and oxygen saturation 99% on room air. The body mass index (BMI) is 17.2 kg/m2. On physical examination, the patient is alert and cooperative. A limp favoring the right leg is noted when the patient is walking. There is mild tenderness on deep palpation of the left lumbar region but no erythema, edema, or warmth. There is a decreased range of motion of the left hip. Which of the following is the most likely diagnosis in this patient?", "answer": "Legg-Calve-Perthes disease", "options": {"A": "Slipped capital femoral epiphysis", "B": "Developmental dysplasia of the hip", "C": "Viral-induced synovitis", "D": "Legg-Calve-Perthes disease", "E": "Pelvic fracture"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 59-year-old female is brought to the emergency department with an acute onset of weakness in her left hand that started 3 hours ago. She has not had numbness or tingling of the hand. Other than recent episodes of blurry vision and headaches, her medical history is unremarkable. She has one daughter who was diagnosed with multiple sclerosis at age 23. Her temperature is 36.7°C (98°F), pulse is 80/min, and blood pressure is 144/84 mm Hg. Examination shows facial erythema. There are mild scratch marks on her arms and torso. Left hand strength is slightly decreased and there is mild dysmetria of the left hand finger-to-nose testing. The remainder of the neurological examination shows no abnormalities. Her laboratory studies shows:\nHematocrit 55%\nLeukocyte count 14,500/mm3\nSegmented neutrophils 61%\nEosinophils 3%\nLymphocytes 29%\nMonocytes 7%\nPlatelet count 690,000/mm3\nHer erythropoietin levels are decreased. CT scan of the head without contrast shows two focal areas of hypo-attenuation in the right parietal lobe. Which of the following is the most appropriate treatment to prevent complications of this patient's underlying condition?\"", "answer": "Repeated phlebotomies", "options": {"A": "Radiation therapy", "B": "Glucocorticoid therapy", "C": "Busulfan", "D": "Imatinib therapy", "E": "Repeated phlebotomies"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old man is undergoing a bone marrow transplantation for treatment of a non-Hodgkin lymphoma that has been refractory to several rounds of chemotherapy and radiation over the past 2 years. He has been undergoing a regimen of cyclophosphamide and total body irradiation for the past several weeks in anticipation of his future transplant. This morning, he reports developing a productive cough and is concerned because he noted some blood in his sputum this morning. The patient also reports pain with inspiration. His temperature is 101°F (38.3°C), blood pressure is 115/74 mmHg, pulse is 120/min, respirations are 19/min, and oxygen saturation is 98% on room air. A chest radiograph and CT are obtained and shown in Figures A and B respectively. Which of the following is the most likely diagnosis?", "answer": "Aspergillus fumigatus", "options": {"A": "Aspergillus fumigatus", "B": "Mycoplasma pneumonia", "C": "Pneumocystis jiroveci pneumonia", "D": "Staphylococcus aureus", "E": "Streptococcus pneumonia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old woman comes to the physician because of a 2-month history of a lump on her neck and a 1-week history of hoarseness. Examination shows a 3-cm, firm, non-tender nodule on the anterior neck. Further evaluation confirms a thyroid malignancy, and she undergoes thyroidectomy. Histopathologic examination of the surgical specimen shows lymphatic invasion. Genetic analysis shows an activating mutation in the RET/PTC genes. Microscopic examination of the surgical specimen is most likely to also show which of the following?", "answer": "Calcified spherules and large oval cells with empty-appearing nuclei", "options": {"A": "Pleomorphic giant cells with numerous atypical mitotic figures", "B": "Sheets of polygonal cells surrounding amyloid deposition", "C": "Calcified spherules and large oval cells with empty-appearing nuclei", "D": "Cuboidal cells arranged spherically around colloid lakes", "E": "Hyperplastic epithelium with colloid scalloping"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 71-year-old woman is brought to the emergency department following a syncopal episode. Earlier in the day, the patient had multiple bowel movements that filled the toilet bowl with copious amounts of bright red blood. Minutes later, she felt dizzy and lightheaded and collapsed into her daughter's arms. The patient has a medical history of diabetes mellitus and hypertension. Her temperature is 99.0°F (37.2°C), blood pressure is 155/94 mmHg, pulse is 82/min, respirations are 15/min, and oxygen saturation is 99% on room air. The patient's exam is notable for fecal occult blood positivity on rectal exam; however, the patient is no longer having bloody bowel movements. The patient's lungs are clear to auscultation and her abdomen is soft and nontender. Labs are ordered as seen below.\n\nHemoglobin: 7.1 g/dL\nHematocrit: 25%\nLeukocyte count: 5,300/mm^3 with normal differential\nPlatelet count: 182,500/mm^3\n\nTwo large bore IV's are placed and the patient is given normal saline. What is the best next step in management?", "answer": "Type and screen", "options": {"A": "Colonoscopy", "B": "CT abdomen", "C": "Fresh frozen plasma", "D": "Packed red blood cells", "E": "Type and screen"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 35-year-old man who works in a shipyard presents with a sharp pain in his left big toe for the past 5 hours. He says he has had this kind of pain before a few days ago after an evening of heavy drinking with his friends. He says he took acetaminophen and ibuprofen for the pain as before but, unlike the last time, it hasn't helped. The patient denies any recent history of trauma or fever. No significant past medical history and no other current medications. Family history is significant for his mother who has type 2 diabetes mellitus and his father who has hypertension. The patient reports regular drinking and the occasional binge on the weekends but denies any smoking history or recreational drug use. The vital signs include pulse 86/min, respiratory rate 14/min, and blood pressure 130/80 mm Hg. On physical examination, the patient is slightly overweight and in obvious distress. The 1st metatarsophalangeal joint of the left foot is erythematous, severely tender to touch, and swollen. No obvious deformity is seen. The remainder of the examination is unremarkable. Joint arthrocentesis of the 1st left metatarsophalangeal joint reveals sodium urate crystals. Which of the following drugs would be the next best therapeutic step in this patient?", "answer": "Naproxen", "options": {"A": "Probenecid", "B": "Morphine", "C": "Aspirin", "D": "Allopurinol", "E": "Naproxen"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An investigator studying epigenetic mechanisms isolates histone proteins, the structural motifs involved in DNA binding and regulation of transcription. The peptide bonds of histone proteins are hydrolyzed and one type of amino acid is isolated. At normal body pH, this amino acid has a net charge of +1 . The investigator performs titration of this amino acid and obtains the graph shown. The isolated amino acid is most likely which of the following?", "answer": "Lysine", "options": {"A": "Serine", "B": "Lysine", "C": "Aspartate", "D": "Histidine", "E": "Proline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 6-month-old boy is brought to a pediatrician by his parents for his first visit after they adopt him from a European country. His parents are concerned about the boy’s short episodes of shaking of his arms and legs; they believe it might be epilepsy. They also note that the child is less responsive than other children of his age. The family is unable to provide any vaccination, birth, or family history. His pulse is 130/min, respiratory rate is 28/min, and blood pressure is 90/50 mm Hg. The boy has a light skin tone and emits a noticeable musty body odor. Which of the following should be supplemented in this patient’s diet?", "answer": "Tyrosine", "options": {"A": "Histidine", "B": "Isoleucine", "C": "Leucine", "D": "Phenylalanine", "E": "Tyrosine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old woman comes to her primary care physician because of an irritating sensation in her nose. She noticed recently that there seems to be a lump in her nose. Her past medical history is significant for pain that seems to migrate around her body and is refractory to treatment. She has intermittently been taking a medication for the pain and recently increased the dose of the drug. Which of the following processes was most likely responsible for development of this patient's complaint?", "answer": "Increased lipoxygenase pathway activity", "options": {"A": "Decreased lipoxygenase pathway activity", "B": "Decreased prostaglandin activity", "C": "Increased allergic reaction in mucosa", "D": "Increased lipoxygenase pathway activity", "E": "Increased mucous viscosity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old man is brought to the emergency department after a witnessed tonic-clonic seizure. His wife says he has had a persistent dry cough for 6 months. During this time period, he has also had fatigue and a 4.5-kg (10-lb) weight loss. The patient has no history of serious illness and does not take any medications. He has smoked 1 pack of cigarettes daily for 35 years. He is confused and oriented only to person. Laboratory studies show a serum sodium concentration of 119 mEq/L and glucose concentration of 102 mg/dL. An x-ray of the chest shows an irregular, poorly demarcated density at the right hilum. Microscopic examination of this density is most likely to confirm which of the following diagnoses?", "answer": "Small cell lung carcinoma", "options": {"A": "Squamous cell lung carcinoma", "B": "Small cell lung carcinoma", "C": "Large cell lung carcinoma", "D": "Bronchial carcinoid tumor", "E": "Lung adenocarcinoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old soldier sustains a gunshot wound to the left side of the chest during a deployment in Syria. The soldier and her unit take cover from gunfire in a nearby farmhouse, and a combat medic conducts a primary survey of her injuries. She is breathing spontaneously. Two minutes after sustaining the injury, she develops severe respiratory distress. On examination, she is agitated and tachypneic. There is an entrance wound at the midclavicular line at the 2nd rib and an exit wound at the left axillary line at the 4th rib. There is crepitus on the left side of the chest wall. Which of the following is the most appropriate next step in management?", "answer": "Needle thoracostomy\n\"", "options": {"A": "Administration of supplemental oxygen", "B": "Endotracheal intubation", "C": "Intravenous administration of fentanyl", "D": "Ultrasonography of the chest", "E": "Needle thoracostomy\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 13-year-old boy is brought to the emergency department by ambulance after suddenly losing consciousness while playing in a soccer tournament. The patient has had 2 episodes of syncope without a discernable trigger over the past year. He has been otherwise healthy. His father died suddenly at the age of 37. He reports lightheadedness and suddenly loses consciousness when physical examination is attempted. Radial pulses are not palpable. An ECG shows ventricular tachycardia with peaks of the QRS twisting around the isoelectric line. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Mutation of myocardial potassium channels", "options": {"A": "Accessory atrioventricular conduction pathway", "B": "Myofibrillar disarray of cardiac septum", "C": "Bicuspid aortic valve", "D": "Defect in interatrial septum", "E": "Mutation of myocardial potassium channels"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man presents after an episode of severe left ankle pain. The pain has resolved, but he decided to come in for evaluation as he has had pain like this before. He says he has experienced similar episodes of intense pain in the same ankle and his left knee in the past, which he associates with eating copious amounts of fatty food during parties. On one occasion the pain was so excruciating, he went to the emergency room, where an arthrocentesis was performed, revealing needle-shaped negatively birefringent crystals and a high neutrophil count in the synovial fluid. His past medical history is relevant for essential hypertension which is managed with hydrochlorothiazide 20 mg/day. His vital signs are stable, and his body temperature is 36.5°C (97.7°F). Physical examination shows a minimally tender left ankle with full range of motion. Which of the following is the most appropriate long-term treatment in this patient?\n ", "answer": "Xanthine oxidase inhibitor", "options": {"A": "Colchicine", "B": "Nonsteroidal antiinflammatory drugs (NSAIDs)", "C": "Uricosuric drug", "D": "Intra-articular steroid injection", "E": "Xanthine oxidase inhibitor"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-year-old boy is presented to a pediatric clinic by his mother with complaints of fever, malaise, and cough for the past 2 days. He frequently complains of a sore throat and has difficulty eating solid foods. The mother mentions that, initially, the boy’s fever was low-grade and intermittent but later became high grade and continuous. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. The past medical history is noncontributory. The boy takes a multivitamin every day. The mother reports that he does well in school and is helpful around the house. The boy’s vital signs include blood pressure 110/65 mm Hg, heart rate 110/min, respiratory rate 32/min, and temperature 38.3°C (101.0°F). On physical examination, the boy appears uncomfortable and has difficulty breathing. His heart is mildly tachycardic with a regular rhythm and his lungs are clear to auscultation bilaterally. Oropharyngeal examination shows that his palatine tonsils are covered with pus and that there is erythema of the surrounding mucosa. Which of the following mediators is responsible for this patient’s elevated temperature?", "answer": "Prostaglandin E2", "options": {"A": "Leukotriene D4", "B": "Thromboxane A2", "C": "Prostaglandin E2", "D": "Prostaglandin I2", "E": "Prostaglandin F2"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 1-year-old male with a history of recurrent pseudomonal respiratory infections and steatorrhea presents to the pediatrician for a sweat test. The results demonstrate a chloride concentration of 70 mEq/L (nl < 40 mEq/L). Which of the following defects has a similar mode of inheritance as the disorder experienced by this patient?", "answer": "Accumulation of glycogen in the lysosome", "options": {"A": "Trinucleotide repeat expansion of CAG on chromosome 4", "B": "Accumulation of glycogen in the lysosome", "C": "Inability to convert carbamoyl phosphate and ornithine into citrulline", "D": "Abnormal production of type IV collagen", "E": "Mutated gene for mitochondrial-tRNA-Lys"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old woman comes to the emergency department because of sharp chest pain and shortness of breath for 1 day. Her temperature is 37.8°C (100°F), pulse is 110/min, respirations are 30/min, and blood pressure is 86/70 mm Hg. CT angiography of the chest shows a large embolus at the right pulmonary artery. Pharmacotherapy with a tissue plasminogen activator is administered. Six hours later, she develops right-sided weakness and slurred speech. Laboratory studies show elevated prothrombin and partial thromboplastin times and normal bleeding time. A CT scan of the head shows a large, left-sided intracranial hemorrhage. Administration of which of the following is most appropriate to reverse this patient's acquired coagulopathy?", "answer": "Aminocaproic acid", "options": {"A": "Protamine sulfate", "B": "Vitamin K", "C": "Plasmin", "D": "Desmopressin", "E": "Aminocaproic acid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "You have been entrusted with the task of finding the causes of low birth weight in infants born in the health jurisdiction for which you are responsible. In 2017, there were 1,500 live births and, upon further inspection of the birth certificates, 108 of these children had a low birth weight (i.e. lower than 2,500 g), while 237 had mothers who smoked continuously during pregnancy. Further calculations have shown that the risk of low birth weight in smokers was 14% and in non-smokers, it was 7%, while the relative risk of low birth weight linked to cigarette smoking during pregnancy was 2%. In other words, women who smoked during pregnancy were twice as likely as those who did not smoke to deliver a low-weight infant. Using this data, you are also asked to calculate how much of the excess risk for low birth weight, in percentage terms, can be attributed to smoking. What is the attributable risk for smoking leading to low birth weight?", "answer": "50%", "options": {"A": "10%", "B": "20%", "C": "30%", "D": "40%", "E": "50%"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 63-year-old woman comes to the physician for a follow-up examination. She has had numbness and burning sensation in her feet for 4 months. The pain is worse at rest and while sleeping. She has hypercholesterolemia and type 2 diabetes mellitus. Current medications include insulin, metformin, and atorvastatin. She has smoked one pack of cigarettes daily for 33 years. Her temperature is 37°C (98.6°F), pulse is 88/min, and blood pressure is 124/88 mm Hg. Examination shows full muscle strength and normal muscle tone in all extremities. Sensation to pinprick, light touch, and vibration is decreased over the soles of both feet. Ankle jerk is 1+ bilaterally. Biceps and triceps reflexes are 2+ bilaterally. Babinski sign is negative bilaterally. Laboratory studies show:\nHemoglobin 11.2 g/dL\nMean corpuscular volume 93 μm3\nHemoglobin A1C 8.2 %\nSerum\nGlucose 188 mg/dL\nWhich of the following is the most appropriate next step in management?\"", "answer": "Venlafaxine therapy", "options": {"A": "Ankle-brachial index", "B": "MRI with contrast of the spine", "C": "Nerve conduction studies", "D": "Vitamin B12 therapy", "E": "Venlafaxine therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 87-year-old man comes to the physician because of progressive involuntary urine dribbling over the past two years. He has to use the restroom more frequently than he used to and feels like he cannot fully empty his bladder. Physical examination shows a palpable suprapubic mass. An ultrasound image of the left kidney is shown. Which of the following is the most likely explanation of this patient's imaging findings?", "answer": "Compression of renal cortex and medulla", "options": {"A": "Short intramural ureter segment", "B": "Compression of renal cortex and medulla", "C": "Posterior urethral valves", "D": "Chronic inflammation of renal interstitium", "E": "Formation of renal parenchymal cysts"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 31-year-old woman, gravida 1, para 0, at 10 weeks' gestation comes to the physician because of a rash on her upper arm that appeared 3 days ago. She has also had headaches and muscle aches for 1 day. She went on a camping trip in Maine 10 days ago. Her temperature is 39°C (102.2°F). A photograph of her rash is shown. Which of the following is the most appropriate pharmacotherapy?", "answer": "Amoxicillin", "options": {"A": "Doxycycline", "B": "Clotrimazole", "C": "Ceftriaxone", "D": "Penicillin G", "E": "Amoxicillin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An investigator studying immune-mediated pulmonary damage performs an autopsy on a bilateral lung transplant recipient who died of hypercapnic respiratory failure. The patient underwent lung transplantation for idiopathic pulmonary fibrosis. Microscopic examination of the lung shows diffuse eosinophilic scarring of the terminal and respiratory bronchioles and near-complete luminal obliteration by polypoidal plugs of granulation tissue. Examination of the skin shows no abnormalities. The findings in this patient are most consistent with which of the following conditions?", "answer": "Chronic graft rejection", "options": {"A": "Transfusion-related acute lung injury", "B": "Recurrence of primary disease", "C": "Chronic graft rejection", "D": "Acute graft-versus-host disease", "E": "Acute graft rejection"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-month-old male infant from a consanguineous marriage presents with severe sunburns and freckling in sun exposed areas. The mother explains that the infant experiences these sunburns every time the infant goes outside despite applying copious amounts of sunscreen. Which of the following DNA repair mechanisms is defective in this child?", "answer": "Nucleotide excision repair", "options": {"A": "Nucleotide excision repair", "B": "Base excision repair", "C": "Mismatch repair", "D": "Homologous recombination", "E": "Non-homologous end joining"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 63-year-old woman comes to the physician because of diarrhea and weakness after her meals for 2 weeks. She has the urge to defecate 15–20 minutes after a meal and has 3–6 bowel movements a day. She also has palpitations, sweating, and needs to lie down soon after eating. One month ago, she underwent a distal gastrectomy for gastric cancer. She had post-operative pneumonia, which was treated with cefotaxime. She returned from a vacation to Brazil 6 weeks ago. Her immunizations are up-to-date. She is 165 cm (5 ft 5 in) tall and weighs 51 kg (112 lb); BMI is 18.6 kg/m2. Vital signs are within normal limits. Examination shows a well-healed abdominal midline surgical scar. The abdomen is soft and nontender. Bowel sounds are hyperactive. Rectal examination is unremarkable. Which of the following is the most appropriate next step in management?", "answer": "Dietary modifications", "options": {"A": "Stool microscopy", "B": "Stool PCR test", "C": "Octreotide therapy", "D": "Metronidazole therapy", "E": "Dietary modifications"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 19-year-old girl comes to her physician with blurred vision upon awakening for 3 months. When she wakes up in the morning, both eyelids are irritated, sore, and covered with a dry crust. Her symptoms improve after she takes a hot shower. She is otherwise healthy and takes no medications. She does not wear contact lenses. Recently, she became sexually active with a new male partner. Her temperature is 37.4°C (99.3°F), and pulse is 88/minute. Both eyes show erythema and irritation at the superior lid margin, and there are flakes at the base of the lashes. There is no discharge. Visual acuity is 20/20 bilaterally. Which of the following is the next best step in management?", "answer": "Lid hygiene and warm compresses", "options": {"A": "Oral doxycycline", "B": "Topical cyclosporine", "C": "Topical erythromycin", "D": "Topical mupirocin", "E": "Lid hygiene and warm compresses"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 50-year-old woman presents with acute onset fever and chills for the past hour. She mentions earlier in the day she felt blue, so she took some St. John’s wort because she was told by a friend that it helps with depression. Past medical history is significant for hypertension, diabetes mellitus, and depression managed medically with captopril, metformin, and fluoxetine. She has no history of allergies. Her pulse is 130/min, the respiratory rate is 18/min, the blood pressure is 176/92 mm Hg, and the temperature is 38.5°C (101.3°F). On physical examination, the patient is profusely diaphoretic and extremely irritable when asked questions. Oriented x 3. The abdomen is soft and nontender with no hepatosplenomegaly. Increased bowel sounds are heard in the abdomen. Deep tendon reflexes are 3+ bilaterally and clonus is elicited. The sensation is decreased in the feet bilaterally. Mydriasis is present. Fingerstick glucose is 140 mg/dL. An ECG shows sinus tachycardia but is otherwise normal. Which of the following is the most likely cause of this patient’s condition?", "answer": "Serotonin syndrome", "options": {"A": "Neuroleptic malignant syndrome", "B": "Diabetic ketoacidosis", "C": "Anaphylactic reaction", "D": "Serotonin syndrome", "E": "Sepsis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 61-year-old Caucasian woman comes to the physician for a routine health maintenance examination. She feels well. She had a normal mammography 10 months ago and a normal serum lipid profile 3 years ago. Two years ago, a pap smear and testing for human papillomavirus were performed and were negative. She had a normal colonoscopy 6 years ago. HIV testing at that time was also negative. Her blood pressure and serum blood glucose were within normal limits during a routine visit 6 months ago. She is a retired university professor and lives together with her husband. She has no children. Menopause occurred 7 years ago. Her father developed colon cancer at the age of 75 years. She does not smoke or drink alcohol. Her only medication is a daily multivitamin. She is 163 cm (5 ft 4 in) tall and weighs 58 kg (128 lb); BMI is 22 kg/m2. Which of the following health maintenance recommendations is most appropriate at this time?", "answer": "Reassurance", "options": {"A": "Serum HIV testing", "B": "Colonoscopy", "C": "Dual-energy x-ray bone absorptiometry", "D": "Fecal occult blood test", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A previously healthy 20-year-old woman comes to her physician because of pain during sexual intercourse. She recently became sexually active with her boyfriend. She has had no other sexual partners. She is frustrated because she has consistently been experiencing a severe, sharp vaginal pain on penetration. She has tried lubricants without significant relief. She has not been able to use tampons in the past due to similar pain with tampon insertion. External vulvar examination shows no abnormalities. She is unable to undergo a bimanual or speculum exam due to intracoital pain with attempted digit or speculum insertion. Testing for Chlamydia trachomatis and Neisseria gonorrhoeae is negative. Which of the following is the best next step in management?", "answer": "Pelvic floor physical therapy", "options": {"A": "Pelvic floor physical therapy", "B": "Vaginal Botox injections", "C": "Sex psychotherapy", "D": "Lorazepam", "E": "Vaginal estrogen cream\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old man is brought to the emergency department because of weakness, headache, and vomiting for 40 minutes. He is an amateur chef and his symptoms started 10 minutes after he ingested pufferfish that he had prepared. On arrival, he is lethargic. His temperature is 37°C (98.6°F), pulse is 120/min, respirations are 8/min, and blood pressure is 92/64 mm Hg. He is intubated and mechanical ventilation is begun. Intravenous fluid resuscitation is started. The cause of this patient's condition exerts its effect by which of the following mechanisms of action?", "answer": "Decrease in cell membrane permeability to sodium ions", "options": {"A": "Decrease in cell membrane permeability to sodium ions", "B": "Increase in cell membrane permeability to chloride ions", "C": "Decrease in cell membrane permeability to calcium ions", "D": "Decrease in cell membrane permeability to potassium ions", "E": "Increase in cell membrane permeability to calcium ions"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A group of scientists studies the effects of cytokines on effector cells, including leukocytes. They observe that interleukin (IL)–12 is secreted by antigen-presenting cells in response to bacterial lipopolysaccharide. Which of the following responses will a CD4+ T cell produce when it is exposed to this interleukin?", "answer": "Cell-mediated immune response", "options": {"A": "Release of granzymes", "B": "Activation of B cells", "C": "Secretion of IL–4", "D": "Cell-mediated immune response", "E": "Response to extracellular pathogens"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old woman presents to the emergency department with pain in her right knee. She states that the pain started last night and rapidly worsened, prompting her presentation for care. The patient has a past medical history of rheumatoid arthritis and osteoarthritis. Her current medications include corticosteroids, infliximab, ibuprofen, and aspirin. The patient denies any recent trauma to the joint. Her temperature is 99.5°F (37.5°C), pulse is 112/min, blood pressure is 100/70 mmHg, respirations are 18/min, and oxygen saturation is 98% on room air. On physical exam, you note erythema and edema of the right knee. There is limited range of motion due to pain of the right knee.\n\nWhich of the following is the best initial step in management?", "answer": "Aspiration", "options": {"A": "CT scan", "B": "Broad spectrum antibiotics", "C": "Aspiration", "D": "Surgical drainage", "E": "Conservative therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 11-year-old boy presents with a 2-day history of uncontrollable shivering. During admission, the patient’s vital signs are within normal limits, except for a fluctuating body temperature registering as low as 35.0°C (95.0°F) and as high as 40.0°C (104.0°F), requiring alternating use of cooling and warming blankets. A complete blood count (CBC) is normal, and a chest radiograph is negative for consolidations and infiltrates. An MRI of the brain reveals a space-occupying lesion infiltrating the posterior hypothalamus and extending laterally. Which of the following additional findings are most likely, based on this patient’s physical examination?", "answer": "Anorexia", "options": {"A": "Hyperphagia", "B": "Anorexia", "C": "Galactorrhea", "D": "Sleep disturbances", "E": "Polyuria"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 9-month-old girl is brought to the emergency department because of a 3-day history of fever, irritability, and discharge from her right ear. She had an episode of ear pain and fever three weeks ago. Her parents did not seek medical advice and the symptoms improved with symptomatic treatment. There is no family history of frequent infections. She appears ill. Her temperature is 39.3°C (102.7°F). Physical examination shows erythema and tenderness in the right postauricular region, and lateral and inferior displacement of the auricle. Otoscopy shows a bulging and cloudy tympanic membrane, with pus oozing out. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11.5 g/dL\nLeukocyte count 15,800/mm3\nSegmented neutrophils 80%\nEosinophils 1%\nLymphocytes 17%\nMonocytes 2%\nPlatelet count 258,000/mm3\nWhich of the following is the most appropriate next step in management?\"", "answer": "CT scan of the temporal bone", "options": {"A": "Topical 0.3% ciprofloxacine therapy", "B": "Phenylephrine nasal drops therapy", "C": "CT scan of the temporal bone", "D": "Oral amoxicillin therapy", "E": "Oral aspirin therapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old boy is brought to the physician with complaints of an ataxic gait and hearing deficits for the past few days. His parents also reported a history of tonic gaze deviation on the right side and the spontaneous remission of a similar episode 6 months ago. His temperature is 37°C (98.6°F), pulse is 88/min, and respirations are 20/min. On physical examination, no abnormality is found, but evoked potential tests are abnormal. Magnetic resonance imaging of the head shows multiple lesions with high T2 signal intensity and one large white matter lesion showing contrast enhancement. His laboratory studies show:\nHemoglobin 12.9 g/dL\nCSF leukocyte count 1000/μL\nCSF gamma globulin 15.4% (normal 7–14%)\nErythrocyte sedimentation rate 16 mm/h\nWhich of the following most likely explains the mechanism of this condition?", "answer": "Type IV hypersensitivity", "options": {"A": "Type I hypersensitivity", "B": "Type II hypersensitivity", "C": "Type III hypersensitivity", "D": "Type IV hypersensitivity", "E": "Type V hypersensitivity"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 75-year-old male is diagnosed with advanced metastatic prostate cancer. After further evaluation and staging, the patient is started on flutamide therapy. Addition of which of the following medications to this patient’s medication regimen would be of greatest benefit in the treatment of this patient’s condition?", "answer": "Leuprolide", "options": {"A": "Leuprolide", "B": "Anastrozole", "C": "Clomiphene", "D": "Tamoxifen", "E": "Cyproterone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old man comes to the physician because of a persistent tingling sensation in the right side of his face. The sensation began after he underwent an extraction of an impacted molar 2 weeks ago. Examination shows decreased sensation of the skin over the right side of the mandible, chin, and the anterior portion of the tongue. Taste sensation is preserved. The affected nerve exits the skull through which of the following openings?", "answer": "Foramen ovale", "options": {"A": "Foramen magnum", "B": "Hypoglossal canal", "C": "Foramen ovale", "D": "Foramen rotundum", "E": "Stylomastoid foramen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3-year-old male presents with his parents to a pediatrician for a new patient visit. The child was recently adopted and little is known about his prior medical or family history. The parents report that the child seems to be doing well, but they are concerned because the patient is much larger than any of the other 3-year-olds in his preschool class. They report that he eats a varied diet at home, and that they limit juice and snack foods. On physical exam, the patient is in the 73rd percentile for weight, 99th percentile for height, and 86th percentile for head circumference. He appears mildly developmentally delayed. He has a fair complexion and tall stature with a prominent sternum. The patient also has joint hypermobility and hyperelastic skin. He appears to have poor visual acuity and is referred to an ophthalmologist, who diagnoses downward lens subluxation of the right eye.\n\nThis child is most likely to develop which of the following complications?", "answer": "Thromboembolic stroke", "options": {"A": "Aortic dissection", "B": "Medullary thyroid cancer", "C": "Osteoarthritis", "D": "Thromboembolic stroke", "E": "Wilms tumor"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 21-year-old woman is evaluated for dry cough, shortness of breath, and chest tightness which occur episodically 1–2 times per week. She notes that she develops significant shortness of breath when running, especially during cool weather. She also says she has 1 episode of coughing attacks during the night per month. She denies any history of tobacco use. Medical history is significant for atopic dermatitis as a child, although she now rarely experiences skin flares. Family history is non-contributory. Vital signs include a temperature of 37.0°C (98.6°F), blood pressure of 115/75 mm Hg, and heart rate of 88/min. Her pulse oximetry is 98% on room air. Physical examination reveals normal air entry and no wheezes. A chest X-ray is normal. Spirometry findings are within normal parameters. Which of the following is the best next step in the management of this patient’s condition?", "answer": "Methacholine challenge test", "options": {"A": "Sweat chloride test", "B": "Methacholine challenge test", "C": "Skin-prick testing", "D": "Ciliary studies", "E": "Clinical observation without further evaluation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 17-year-old boy is brought to the physician because of swelling of his face and legs for 5 days. He immigrated to the United States from Korea with his family 10 years ago. He has been healthy except for an episode of sore throat 2 weeks ago. His younger sister has type 1 diabetes mellitus. His temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 145/87 mm Hg. Examination shows periorbital edema and 3+ pitting edema of the lower extremities. Laboratory studies show:\nHemoglobin 13.9 g/dL\nLeukocyte count 8,100/mm3\nSerum\nGlucose 78 mg/dL\nAlbumin 2.4 g/dL\nHepatitis B surface antigen positive\nHepatitis B surface antibody negative\nComplement C4 decreased\nUrine\nBlood negative\nProtein 4+\nGlucose negative\nProtein/creatinine ratio 8.1 (N ≤ 0.2)\nFurther evaluation is most likely to show which of the following additional findings?\"", "answer": "Subepithelial deposits on renal biopsy", "options": {"A": "Subepithelial deposits on renal biopsy", "B": "Eosinophilic nodules on renal biopsy", "C": "Antineutrophil cytoplasmic antibody level in serum", "D": "Normal-appearing glomeruli on renal biopsy", "E": "Increased IgA levels in serum"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man comes to the physician because of fatigue and joint pain for 8 months. He has pain in both knees, both elbows, and diffuse muscle pain. He does not have dyspnea. He also had several episodes of a nonpruritic rash on his lower extremities. Eight years ago, the patient was diagnosed with hepatitis C. His temperature is 37.9°C (100.2°F), pulse is 90/min, and blood pressure is 140/90 mm Hg. Examination of the lower extremities shows raised purple papules that do not blanch when pressure is applied. Cardiopulmonary examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13.9 g/dL\nLeukocyte count 8,500/mm3\nPlatelets 160,000/mm3\nSerum\nCreatinine 1.1 mg/dL\nALT 123 U/L\nAST 113 U/L\nFurther evaluation of this patient is most likely to show which of the following findings?\"", "answer": "Hypocomplementemia", "options": {"A": "Elevated perinuclear anti-neutrophil cytoplasmic antibodies", "B": "Elevated IgA in serum", "C": "Granulomatous inflammation of vessels", "D": "Positive pathergy test", "E": "Hypocomplementemia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 46-year-old homeless man was found wandering aimlessly in the supermarket. On examination, he is confused and said that the President appointed men to kill him because he is disclosing state secrets to extraterrestrial organisms. The man also has horizontal nystagmus and an ataxic gait. What is the most likely cause of the clinical presentation?", "answer": "Necrosis of mammillary bodies", "options": {"A": "Hypothyroidism", "B": "Trinucleotide repeat disorder", "C": "Neurofibrillary tangles", "D": "Atrophy of globus pallidus", "E": "Necrosis of mammillary bodies"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 30-year-old man comes to the physician because of an episode of bloody vomiting this morning and a 1-week history of burning upper abdominal pain. Two weeks ago, he sustained a head injury and was in a coma for 3 days. An endoscopy shows multiple, shallow hemorrhagic lesions predominantly in the gastric fundus and greater curvature. Biopsies show patchy loss of epithelium and an acute inflammatory infiltrate in the lamina propria that does not extend beyond the muscularis mucosa. Which of the following is the most likely diagnosis?", "answer": "Erosive gastritis", "options": {"A": "Type B gastritis", "B": "Dieulafoy lesion", "C": "Cushing ulcer", "D": "Penetrating ulcer", "E": "Erosive gastritis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old medical student comes to the physician for a chest x-ray to rule out active pulmonary tuberculosis. He needs a medical and radiological report before starting a medical internship in South Africa. He has no history of serious illness and does not complain of any symptoms. He has smoked 1 pack of cigarettes daily for the past 6 years. He does not drink alcohol. He is 190 cm (6 ft 3 in) tall and weighs 75 kg (165 lbs); BMI is 20.8 kg/m2. His temperature is 37°C (98.6°F), pulse is 80/min, respirations are 18/min, and blood pressure is 128/89 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The x-ray of the chest shows a small pneumothorax (rim of < 2 cm) between the upper left lung margin and the chest wall. Which of the following is the most appropriate next step in management of this patient?", "answer": "Observation and follow-up x-ray", "options": {"A": "Emergent needle thoracostomy", "B": "Observation and follow-up x-ray", "C": "Immediate intubation and assisted ventilation", "D": "CT of the chest", "E": "Urgent chest tube placement"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 47-year-old woman presents to her physician for a routine checkup. She is in good health and has no complaints. Past medical history is significant for type 2 diabetes mellitus and obesity. She recently started metformin and is tolerating the mild side effects, but her fasting blood glucose levels range from 160–190 mg/dL. Today, her blood pressure is 125/82 mm Hg, the heart rate is 90/min, the respiratory rate is 17/min, and the temperature is 37.0°C (98.6°F). On physical exam, she appears well developed and obese. Her heart has a regular rate and rhythm and his lungs are clear to auscultation bilaterally. Her fasting glucose level is 175 mg/dL and her A1c is 7.1%. Her physician decides to add canagliflozin to her current treatment regimen. Which of the following should be evaluated before starting this medication?", "answer": "Serum creatinine", "options": {"A": "γ-glutamyltransferase", "B": "β-hCG levels", "C": "Alanine aminotransferase", "D": "Serum creatinine", "E": "Atrial natriuretic peptide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old primigravid woman comes to the emergency department because of a 12-hour history of lower abdominal pain and vaginal bleeding. She also had nausea and fatigue for the past 3 weeks. Her last menstrual period was 8 weeks ago. Prior to that, her menses occurred regularly at 30-day intervals and lasted for 4 days. There is no history of medical illness, and she takes no medications. Her temperature is 37°C (98.6°F), pulse is 95/min, and blood pressure is 100/70 mm Hg. Pelvic examination is painful and shows a uterus consistent in size with a 13-week gestation. A urine pregnancy test is positive. β-HCG level is 106,000 mIU/mL (N < 5 mIU/mL). Transvaginal ultrasonography shows unclear, amorphous fetal parts and a large placenta with multiple cystic spaces. Which of the following is the most likely cause of this patient's condition?", "answer": "Trophoblastic proliferation with chorionic villi distention", "options": {"A": "Placenta implantation into myometrium", "B": "Malignant transformation of trophoblastic tissue", "C": "Trophoblastic proliferation with chorionic villi distention", "D": "Malpositioned placenta overlying the cervix", "E": "Embryonic death with cervical dilation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old man presents with a 3-day history of cough and fever. He says that he recently became a factory worker in a huge plant that is involved in the polyvinyl chloride (PVC) polymerization process. Because he has heard about occupational diseases specifically related to this particular industry, he asks the physician whether his new job is associated with any serious conditions. His physician mentions that polyvinyl chloride is a known chemical carcinogen and that workers who have been exposed to it are known to be at increased risk of developing a particular type of cancer. Which of the following cancers is the physician most likely talking about?", "answer": "Hepatic angiosarcoma", "options": {"A": "Adenocarcinoma of the small intestine", "B": "Bronchogenic carcinoma", "C": "Hepatic angiosarcoma", "D": "Urothelial carcinoma", "E": "Malignant lymphoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 29-year-old African-American male comes to the physician with a 2-week history of progressive fatigue and shortness of breath on exertion. Last week he noticed that his eyes were gradually turning yellow and his urine was dark. He has a family history of type II diabetes. He denies changes in urinary frequency, dysuria, or nocturia. His temperature is 37°C (98.6° F), blood pressure is 120/80 mmHg, and heart rate is 80/min. Examination shows pale conjunctivae, splenomegaly, and jaundice. There is no lymphadenopathy. Laboratory studies show:\nHematocrit 19.5%\nHemoglobin 6.5 g/dL\nWBC count 11,000/mm3\nPlatelet count 300,000/mm3\nReticulocyte count 8%\nSerum\nTotal bilirubin 6 mg/dL\nDirect bilirubin 1.0 mg/dL\nUrea nitrogen 9 mg/dL\nCreatinine 1 mg/dL\nLactate dehydrogenase 365 U/L\nPeripheral blood smear shows gross polychromasia with nucleated red blood cells and spherocytes. Direct Coombs' test is positive. Which of the following is the most likely diagnosis?\"", "answer": "Autoimmune hemolytic anemia\n\"", "options": {"A": "Hereditary spherocytosis", "B": "Paroxysmal nocturnal hemoglobinuria", "C": "Alpha thalassemia", "D": "Spur cell hemolytic anemia", "E": "Autoimmune hemolytic anemia\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old woman is admitted to the intensive care unit (ICU) with hematemesis and shock. Five days ago she had a severe fever 40.0℃ (104.0℉), retro-orbital pain, nausea, and myalgias. The high temperatures decreased over a few days, but she developed severe abdominal pain and bleeding gums. A single episode of hematemesis occurred prior to ICU admission. She travels to Latin America every winter. Two weeks ago, she traveled to Brazil and spent most of her time outdoors. She is restless. The temperature is 38.0℃ (100.4℉), the pulse is 110/min, the respiration rate is 33/min, and the blood pressure is 90/70 mm Hg. Conjunctival suffusion is seen. The extremities are cold. A maculopapular rash covers the trunk and extremities. Ecchymoses are observed on the lower extremities. The lung bases reveal absent sounds with dullness to percussion. The abdomen is distended. The liver edge is palpable and liver span is 15 cm. Shifting dullness is present. The laboratory studies show the following:\nLaboratory test\nHemoglobin 16.5 g/dL\nLeukocyte count 3500/mm3\nSegmented neutrophils 55%\nLymphocytes 30%\nPlatelet count 90,000/mm3\nSerum\nAlanine aminotransferase (ALT) 75 U/L\nAspartate aminotransferase (AST) 70 U/L\nTotal bilirubin 0.8 mg/dL\nDirect bilirubin 0.2 mg/dL\nWhich of the following is the most likely diagnosis?", "answer": "Dengue fever", "options": {"A": "Chikungunya virus infection", "B": "Dengue fever", "C": "Chagas disease", "D": "Yellow fever", "E": "Zika virus infection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old boy is brought to the emergency department after he vomited and said he was having double vision in school. He also says that he has been experiencing morning headaches, nausea, and dizziness over the last month. He has no past medical history and is not taking any medications. Physical exam reveals a broad-based gait, dysmetria on finger-to-nose testing, and nystagmus. Both serum and urine toxicology are negative, and radiography reveals a solid mass in the midline cerebellum that enhances after contrast administration. Biopsy of this lesion reveals cells of primitive neuroectodermal origin. Which of the following would most likely be seen on histology of this lesion?", "answer": "Rosettes with small blue cells", "options": {"A": "Eosinophilic corkscrew fibers", "B": "Foamy cells and high vascularity", "C": "Perivascular pseudorosettes", "D": "Rosettes with small blue cells", "E": "Tooth enamel-like calcification"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 16-year-old boy is brought to the emergency department following a car accident in which he suffered multiple injuries. He is accompanied by his mother. She reports that his medical history is notable only for recurrent sinusitis and otitis as a child. He lost a significant amount of blood from the accident, and he is transfused two units of O-negative blood on arrival at the emergency department. Shortly thereafter, he complains of itching and increasing shortness of breath. He develops stridor. Which of the following could have prevented this reaction?", "answer": "Administering washed blood products", "options": {"A": "Pre-transfusion acetaminophen", "B": "Pre-transfusion diphenhydramine", "C": "Administering type-specific blood", "D": "Administering IVIG with transfusion", "E": "Administering washed blood products"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Three hours after undergoing a total right hip replacement, a 71-year-old woman has tingling around the lips and numbness in her fingertips. Her surgery was complicated by unintentional laceration of the right femoral artery that resulted in profuse bleeding. She appears uncomfortable. Examination shows an adducted thumb, extended fingers, and flexed metacarpophalangeal joints and wrists. Tapping on the cheeks leads to contraction of the facial muscles. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Calcium chelation", "options": {"A": "Acute kidney injury", "B": "Calcium chelation", "C": "Intravascular hemolysis", "D": "Parathyroid ischemia", "E": "Metabolic acidosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old man presents to the office for evaluation of a lesion on his upper arm that appeared a few months ago and has not healed. A patient appears healthful but has a history of cardiovascular disease. He states that his friend at the industrial ammunition factory where he works told him he should “get it looked at.” The patient admits to some nausea, vomiting, and diarrhea over the past year, but he states that he “feels fine now.” On physical examination, the lesion is an erythematous, scaly, ulcerated plaque on the flexor surface of his upper arm. The rest of the exam is within normal limits. What is the most likely diagnosis?", "answer": "Squamous cell carcinoma (SCC)", "options": {"A": "Squamous cell carcinoma (SCC)", "B": "Actinic keratosis", "C": "Erysipelas", "D": "Contact dermatitis", "E": "Erythema multiforme"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 30-year-old man is brought to the emergency department with complaints of fevers to 39.0℃ (102.2℉) and diarrhea for the past 12 hours. There is no history of headaches, vomiting, or loss of consciousness. The past medical history is unobtainable because the patient recently immigrated from abroad and has a language barrier, but his wife says that her husband had a motor vehicle accident when he was a teenager that required emergent surgery. He is transferred to the ICU after a few hours in the ED due to dyspnea, cyanosis, and hemodynamic collapse. There are no signs of a meningeal infection. The blood pressure is 70/30 mm Hg at the time of transfer. A chest X-ray at the time of admission shows interstitial infiltrates without homogeneous opacities. The initial laboratory results reveal metabolic acidosis, leukopenia with a count of 2000/mm3, thrombocytopenia (15,000/mm3), and a coagulation profile suggesting disseminated intravascular coagulation. A peripheral smear is performed as shown in the accompanying image. Despite ventilatory support, administration of intravenous fluids, antibiotics, and vasopressor agents, the patient dies the next day. The gram stain from the autopsy specimen of his lungs reveals gram-positive, lancet-shaped diplococci occurring singly and in chains. Which of the following organisms is the most likely cause for the patient’s condition?", "answer": "Streptococcus pneumoniae", "options": {"A": "Staphylococcus aureus", "B": "Streptococcus pyogene", "C": "Streptococcus pneumoniae", "D": "Neisseria meningitidis", "E": "Non-typeable H. influenzae"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 79-year-old woman is brought to the emergency department by her husband 20 minutes after losing consciousness. She was walking briskly with her husband when she collapsed suddenly. Her husband says that she regained consciousness after 1 minute. She has had episodes of mild chest pain for the past 2 months, especially when working in the garden. Physical examination shows a grade 3/6 systolic ejection murmur. The intensity of the murmur decreases with the handgrip maneuver and does not change with inspiration. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Dystrophic calcification on the aortic valve", "options": {"A": "Cystic medial degeneration of the aortic root", "B": "Sterile platelet thrombi on the mitral valve", "C": "Infected fibrin aggregates on the tricuspid valve", "D": "Dystrophic calcification on the aortic valve", "E": "Granulomatous nodules on the mitral valve"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A researcher is studying receptors that respond to epinephrine in the body and discovers a particular subset that is expressed in presynaptic adrenergic nerve terminals. She discovers that upon activation, these receptors will lead to decreased sympathetic nervous system activity. She then studies the intracellular second messenger changes that occur when this receptor is activated. She records these changes and begins searching for analogous receptor pathways. Which of the following receptors would cause the most similar set of intracellular second messenger changes?", "answer": "Dopamine receptors in the brain", "options": {"A": "Aldosterone receptors in the kidney", "B": "Dopamine receptors in the brain", "C": "Growth hormone receptors in the musculoskeletal system", "D": "Muscarinic cholinoreceptors in the gastrointestinal tract", "E": "Vasopressin receptors in the kidney"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old man comes to the emergency department because of a dry mouth and blurred vision for the past 30 minutes. Prior to this, he was on a road trip and started to feel nauseous, dizzy, and fatigued, so his friend gave him a drug that had helped in the past. Physical examination shows dry mucous membranes and dilated pupils. The remainder of the examination shows no abnormalities. Administration of which of the following drugs is most likely to cause a similar adverse reaction in this patient?", "answer": "Oxybutynin", "options": {"A": "Oxycodone", "B": "Oxybutynin", "C": "Pilocarpine", "D": "Phenylephrine", "E": "Loratadine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An inconsolable mother brings her 2-year-old son to the emergency room after finding a large amount of bright red blood in his diaper, an hour ago. She states that for the past week her son has been having crying fits while curling his legs towards his chest in a fetal position. His crying resolves either after vomiting or passing fecal material. Currently, the child is in no apparent distress. Physical examination with palpation in the gastric region demonstrates no acute findings. X-ray of the abdominal area demonstrates no acute findings. His current temperature is 36.5°C (97.8°F), heart rate is 93/min, blood pressure is 100/64 mm Hg, and respiratory rate is 26/min. His weight is 10.8 kg (24.0 lb), and height is 88.9 cm (35.0 in). Laboratory tests show the following:\nRBC count 5 million/mm3\nHematocrit 36%\nHemoglobin 12 g/dL\nWBC count 6,000/mm3\nMean corpuscular volume 78 fL\nWhat is the most likely cause of this condition?", "answer": "Failure of the vitelline duct to close", "options": {"A": "Failure of the vitelline duct to open", "B": "Failure of the vitelline duct to close", "C": "Problem with bilirubin conjugation", "D": "Problem with bilirubin uptake", "E": "Elevated anti-mitochondrial uptake"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man is brought to the emergency department by police for abnormal behavior in a mini-market. The patient was found passed out in the aisle, and police were unable to arouse him. The patient has a past medical history of alcohol abuse and is not currently taking any medications according to his medical records. His temperature is 99.5°F (37.5°C), blood pressure is 120/87 mmHg, pulse is 50/min, respirations are 5/min, and oxygen saturation is 93% on room air. On physical exam, the patient is minimally responsive. He responds to painful stimuli by retracting his limbs and groaning, but otherwise does not answer questions or obey commands. Which of the following is most likely to be found in this patient?", "answer": "Miosis", "options": {"A": "Conjunctival hyperemia", "B": "Hyperactive bowel sounds", "C": "Miosis", "D": "Mydriasis", "E": "Visual hallucinations"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 8-year-old boy with asthma is brought to the physician because of a 2-week history of facial pain and congestion. His mother states that the nasal discharge was initially clear, but it has become thicker and more purulent over the last week. He has tried multiple over-the-counter oral decongestants and antihistamines, with minimal relief. Current medications include cetirizine, intranasal oxymetazoline, and albuterol. His temperature is 37.7°C (99.8°F), pulse is 100/min, respirations are 14/min, and blood pressure is 110/70 mm Hg. Examination shows congested nasal mucosa with purulent discharge from the nares bilaterally. There is tenderness to palpation over the cheeks, with no transillumination over the maxillary sinuses. Which of the following is the most likely predisposing factor for this patient's current condition?", "answer": "Viral upper respiratory tract infection", "options": {"A": "Nasal polyps", "B": "Viral upper respiratory tract infection", "C": "Asthma", "D": "Foreign body", "E": "Recent use of antihistamines\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 76-year-old woman is brought to the physician because of lesions on her left arm. She first noticed them 3 months ago and they have grown larger since that time. She has not had any pain or pruritus in the area. She has a history of invasive ductal carcinoma of the left breast, which was treated with mastectomy and radiation therapy 27 years ago. Since that time, she has had lymphedema of the left arm. Physical examination shows extensive edema of the left arm. There are four coalescing, firm, purple-blue nodules on the left lateral axillary region and swelling of the surrounding skin. Which of the following is the most likely diagnosis?", "answer": "Angiosarcoma", "options": {"A": "Cellulitis", "B": "Thrombophlebitis", "C": "Angiosarcoma", "D": "Melanoma", "E": "Kaposi sarcoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 39-year-old female presents to the clinic with the complaints of dry skin for a few months. She adds that she also has constipation for which she started eating vegetables and fruits but with no improvement. She lives with her husband and children who often complain when she turns the air conditioning to high as she cannot tolerate low temperatures. She has gained 5 kgs (11.2 lb) since her last visit 2 months back although her diet has not changed much. Her past medical history is relevant for cardiac arrhythmias and diabetes. She is on several medications currently. Her temperature is 98.6° F (37° C), respirations are 15/min, pulse is 57/min and blood pressure is 132/98 mm Hg. A physical examination is within normal limits. Thyroid function test results are given below:\nSerum\nTSH: 13.0 μU/mL\nThyroxine (T4): 3.0 μg/dL\nTriiodothyronine (T3): 100 ng/dL\nWhich of the following medications is most likely to be responsible for her symptoms?", "answer": "Amiodarone", "options": {"A": "Digoxin", "B": "Amiodarone", "C": "Metformin", "D": "Theophylline", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old man with a past medical history of previous myocardial infarction, angina, hypertension, hyperlipidemia, diabetes mellitus, peripheral vascular disease, and below knee amputation has developed new chest pain. His medication includes insulin, hydrochlorothiazide, lisinopril, metoprolol, daily aspirin, atorvastatin, and nitroglycerin as needed. His vitals include: blood pressure 135/87 mm Hg, pulse 52/min, and respirations 17/min. Coronary arteriography shows a reduced ejection fraction, a 65% stenosis of the left anterior descending artery, and a 75% stenosis of the left circumflex artery. Which of the following is the recommended treatment for the patient?", "answer": "Coronary artery bypass grafting (CABG)", "options": {"A": "Coronary artery bypass grafting (CABG)", "B": "Heparin", "C": "Increased beta blocker dosage", "D": "Extended release nitrate therapy", "E": "Angioplasty with stent placement"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A newborn infant is born at 41 weeks gestation to a healthy G1P0 mother. The delivery was complicated by shoulder dystocia. The infant is in the 89th and 92th percentiles for height and weight, respectively. The mother's past medical history is notable for diabetes mellitus and obesity. Immediately after birth, the child's temperature is 99°F (37.2°C), blood pressure is 90/50 mmHg, pulse is 120/min, and respirations are 24/min. The child demonstrates a strong cry and pink upper and lower extremities bilaterally. The left arm is adducted and internally rotated at the shoulder and extended at the elbow. Extension at the elbow and flexion and extension of the wrist appear to be intact in the left upper extremity. The right upper extremity appears to have normal strength and range of motion in all planes. Which of the following sets of nerves or nerve roots is most likely affected in this patient?", "answer": "C5 and C6 nerve roots", "options": {"A": "Axillary nerve only", "B": "C5 and C6 nerve roots", "C": "C5, C6, and C7 nerve roots", "D": "Musculocutaneous nerve only", "E": "Suprascapular nerve only"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Activation of the renin-angiotensin-aldosterone system yields a significant physiological effect on renal blood flow and filtration. Which of the following is most likely to occur in response to increased levels of Angiotensin-II?", "answer": "Decreased renal plasma flow, increased filtration fraction", "options": {"A": "Increased renal plasma flow, decreased filtration fraction", "B": "Increased renal plasma flow, increased filtration fraction", "C": "Decreased renal plasma flow, decreased filtration fraction", "D": "Decreased renal plasma flow, increased filtration fraction", "E": "Decreased renal plasma flow, increased glomerular capillary oncotic pressure"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old woman presents to her family physician because of sinusitis and nasal drainage for 3 months. The nasal drainage is purulent and occasionally hemorrhagic. She has only temporary improvement after trying multiple over the counter medications. Over the last 2 weeks, she also has fatigue and joint pain, mainly affecting the ankles, knees, and wrists. Vital signs include: temperature 36.9°C (98.4°F), blood pressure 142/91 mm Hg, and pulse 82/min. On examination, there is inflammation and bleeding of the nasal mucosa, along with tenderness to percussion over the maxillary sinuses. Urine dipstick reveals 4+ microscopic hematuria and 2+ proteinuria. Which of the following is the most likely diagnosis?", "answer": "Granulomatosis with polyangiitis", "options": {"A": "Polyarteritis nodosa", "B": "Churg-Strauss syndrome", "C": "Granulomatosis with polyangiitis", "D": "Immunoglobulin A nephropathy", "E": "Sarcoidosis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 64-year-old male presents to the emergency room complaining of chest pain. He reports a pressure-like sensation over his sternum that radiates into his jaw. The pain came on suddenly 2 hours ago and has been constant since then. His past medical history is notable for a stable abdominal aortic aneurysm, hypertension, diabetes, and hyperlipidemia. He takes aspirin, enalapril, spironolactone, atorvastatin, canagliflozin, and metformin. His temperature is 99.1°F (37.3°C), blood pressure is 155/85 mmHg, pulse is 115/min, and respirations are 22/min. On exam, he is diaphoretic and in moderate distress. He is admitted for further management and does well after initial stabilization. He is seen two days later by the admitting team. This patient is at increased risk for a complication that is characterized by which of the following?", "answer": "Friction rub", "options": {"A": "Friction rub", "B": "Cardiac tamponade", "C": "Intra-cardiac shunt", "D": "Mitral insufficiency", "E": "Ventricular fibrillation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 69-year-old woman is rushed to the emergency room by her daughter after she found her unconscious. Bruises are visible on the patient’s torso and limbs, and it is evident that she has epistaxis. Her daughter says that the patient was diagnosed with immune thrombocytopenic purpura at 61 years of age and has not had a normal thrombocyte count since the time of diagnosis. She was treated with corticosteroids, which were discontinued several weeks ago. Her current platelet count is 4,000/mm3. Which of the following is the best next step in the treatment of this patient?", "answer": "Administration of intravenous immunoglobulins", "options": {"A": "Splenectomy", "B": "Platelet transfusion", "C": "Administration of intravenous immunoglobulins", "D": "Continuation of corticosteroids", "E": "Stem cell transplantation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 9-year-old girl is admitted to the hospital with a one-day history of acute abdominal pain and vomiting. She also has a two-day history of fever, headache, and neck pain. Her immunizations are up-to-date. She is confused and oriented only to place and person. Her temperature is 39.7°C (103.5°F), pulse is 148/min, blood pressure is 90/50 mm Hg, and respiratory rate is 28/min. Cervical range of motion is limited by pain. The remainder of the neurologic examination shows no abnormalities. Laboratory studies show:\nHemoglobin 10.9 g/dL\nLeukocyte count 44,000/mm3\nSerum\npH 7.33\nNa+ 130 mEq/L\nCl- 108 mEq/L\nK+ 6.1 mEq/L\nHCO3- 20 mEq/L\nUrea nitrogen 34 mg/dL\nGlucose 180 mg/dL\nCreatinine 2.4 mg/dL\nUrine ketones negative\nA CT scan of the head shows enhancement of the arachnoid and pia mater. Cerebrospinal fluid analysis shows a leukocyte count of 3,400/μL (90% neutrophils), a glucose concentration of 50 mg/dL, protein concentration of 81 mg/dL, and no erythrocytes. Gram stain of the CSF shows gram-negative diplococci. This patient is at increased risk for which of the following complications?\"", "answer": "Adrenal hemorrhage", "options": {"A": "Pancreatitis", "B": "Adrenal hemorrhage", "C": "Vesicular skin eruptions", "D": "Temporal lobe inflammation", "E": "Deep neck abscess"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 48-year-old woman comes to the physician because of a 6-month history of muscle stiffness, myalgia, and a 7-kg (15-lb) weight gain. Her last menstrual period was 4 months ago. Physical examination shows cold, dry skin, and proximal muscle weakness. Deep tendon reflexes are 2+ bilaterally, with delayed relaxation. The creatine kinase level is 2,940 U/L. Which of the following is the most appropriate next step in diagnosis?", "answer": "Thyroid function tests", "options": {"A": "Thyroid function tests", "B": "Serum assay for muscle specific tyrosine kinase antibody", "C": "Muscle biopsy", "D": "Serum electrolytes", "E": "Repetitive nerve stimulation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 73-year-old man presents to the emergency department with acute substernal chest pain that began a few hours ago. The pain is described as a “pressure” that radiates to his left arm. His past medical history is significant for hypertension and hyperlipidemia. He is on chlorthalidone for his hypertension and simvastatin for hyperlipidemia. He has a 30 pack-year history of smoking and drinks 1-2 beers on weekends. His EKG shows ST depressions in the anterior precordial leads and he is given the proper medications and sent for emergency revascularization. Seven days later, he develops dyspnea that worsens in the supine position. Bibasilar crackles are heard on pulmonary auscultation. Cardiac exam reveals a new 3/6 holosystolic murmur best heard at the left sternal border. What is the most likely etiology of this patient’s new symptoms?", "answer": "Papillary muscle rupture", "options": {"A": "Aortic stenosis", "B": "Ventricular wall aneurysm", "C": "Restrictive pericarditis", "D": "Papillary muscle rupture", "E": "Arrhythmia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old woman is brought to the emergency department for a severe throbbing headache, nausea, and photophobia for 3 hours. She has severe occipital pain and chest tightness. Prior to onset of symptoms, she had attended a networking event where she had red wine and, shortly after, a snack consisting of salami and some dried fruits. The patient has recurrent migraine headaches and depression, for which she takes medication daily. She is mildly distressed, diaphoretic, and her face is flushed. Her temperature is 37.0°C (98.6 F), pulse is 90/min, respirations are 20/min, and blood pressure is 195/130 mmHg. She is alert and oriented. Deep-tendon reflexes are 2+ bilaterally. This patient's symptoms are most likely caused by a side effect of which of the following medications?", "answer": "Phenelzine", "options": {"A": "Ibuprofen", "B": "Verapamil", "C": "Phenelzine", "D": "Topiramate", "E": "Valproic acid"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A group of scientists is verifying previous research on DNA replication. The diagram below illustrates the theoretical DNA replication process in bacteria such as E. coli. Which of the following enzymes would need to be decreased to prevent the removal of RNA primers formed in the lagging strand?", "answer": "DNA polymerase I 5’ to 3’ exonuclease activity", "options": {"A": "Helicase", "B": "DNA polymerase I 3’ to 5’ exonuclease activity", "C": "DNA polymerase III 3’ to 5’ exonuclease activity", "D": "DNA polymerase I 5’ to 3’ exonuclease activity", "E": "DNA ligase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 58-year-old man is brought to the emergency department by his family because of severe upper back pain, which he describes as ripping. The pain started suddenly 1 hour ago while he was watching television. He has hypertension for 13 years, but he is not compliant with his medications. He denies the use of nicotine, alcohol or illicit drugs. His temperature is 36.5°C (97.7°F), the heart rate is 110/min and the blood pressure is 182/81 mm Hg in the right arm and 155/71 mm Hg in the left arm. CT scan of the chest shows an intimal flap limited to the descending aorta. Intravenous opioid analgesia is started. Which of the following is the best next step in the management of this patient condition?", "answer": "Intravenous esmolol", "options": {"A": "Emergency surgical intervention", "B": "Oral metoprolol and/or enalapril", "C": "Sublingual nitroglycerin", "D": "Intravascular ultrasound", "E": "Intravenous esmolol"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old man comes to the physician because of several episodes of painless bloody urine over the past 6 months. The episodes are not related to physical activity. He has had frequent nosebleeds since early childhood and an episode of heavy bleeding after a tooth extraction one year ago. He smokes one pack of cigarettes daily. He drinks 1 to 2 beers on social occasions. He appears pale. His vital signs are within normal limits. Physical examination shows several small hematomas in different stages of healing over his arms and legs. Examination of the extremities shows decreased passive range of motion with crepitus in both ankles. His abdomen is soft and nontender. Laboratory studies show:\nHemoglobin 9.5 mg/dL\nLeukocyte count 5000/mm3\nPlatelet count 240,000/mm3\nBleeding time 5 minutes\nProthrombin time 14 seconds\nPartial thromboplastin time 68 seconds\nUrine\nRBC 30–40/hpf\nRBC casts negative\nWBC none\nProtein negative\nAn x-ray of the pelvis shows no abnormalities. Further evaluation of this patient is most likely to show which of the following findings?\"", "answer": "Intraarticular iron deposition", "options": {"A": "Evasive behavior when asked about the hematomas", "B": "Palpable spleen below the left costal margin", "C": "Nephrolithiasis", "D": "Intraarticular iron deposition", "E": "Hemosiderin-laden alveolar macrophages\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old man comes to the physician because of a 3-week history of progressive diarrhea and a 2.2-kg (5-lb) weight loss. During the past week, he has had six small bloody stools daily. He is employed as a sales manager and regularly flies to South America. He has HIV, gastroesophageal reflux disease, and hypertension. Current medications include chlorthalidone, omeprazole, emtricitabine, tenofovir, and efavirenz. He reports taking efavirenz irregularly. He is 175 cm (5 ft 9 in) tall and weighs 64 kg (143 lb); BMI is 22 kg/m2. His temperature is 38.1°C (100.6°F), pulse is 91/min, and blood pressure is 116/69 mm Hg. The abdomen is scaphoid. Bowel sounds are normal. His CD4+ T-lymphocyte count is 44/mm3 (N ≥ 500), leukocyte count is 6,000/mm3, and erythrocyte sedimentation rate is 12 mm/h. Colonoscopy shows areas of inflammation scattered throughout the colon with friability, granularity, and shallow linear ulcerations. The intervening mucosa between areas of inflammation appears normal. A biopsy specimen is shown. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Cytomegalovirus", "options": {"A": "Cytomegalovirus", "B": "Hepatitis A virus", "C": "Adverse effect of medications", "D": "Cryptosporidium parvum", "E": "Clostridioides difficile"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 43-year-old female presents to her primary care physician complaining of a gradually enlarging neck mass. She reports that she first developed a firm nodular midline mass on the anterior aspect of her neck two months ago. She is otherwise healthy and takes no medications. A fine-needle aspiration is performed and a histological sample of the specimen is shown. Which of the following is the most likely diagnosis?", "answer": "Papillary thyroid carcinoma", "options": {"A": "Medullary thyroid carcinoma", "B": "Follicular thyroid carcinoma", "C": "Papillary thyroid carcinoma", "D": "B-cell lymphoma", "E": "Anaplastic thyroid carcinoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old G1P0 female of Middle Eastern descent gives birth to a male infant at 38 weeks’ gestation. The child is in the 15th percentile for both height and weight. Over the course of the first six months of the child’s life, he develops multiple severe skin and mucosal infections characterized by dramatically elevated white blood cell counts. The patient also demonstrates mental retardation soon after birth. A thorough hematologic analysis via flow cytometry reveals that the child's neutrophils that lack Sialyl-Lewis X. Which of the following processes is likely deficient in this patient?", "answer": "Rolling", "options": {"A": "Chemoattraction", "B": "Rolling", "C": "Tight adhesion", "D": "Diapedesis", "E": "Transmigration through the extracellular matrix"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old girl is brought to the physician by her mother for a 2-day history of abdominal pain, nausea, vomiting, diarrhea, and decreased appetite. Her last menstrual period was 3 weeks ago. Her temperature is 37.6°C (99.7°F). Abdominal examination shows tenderness to palpation with guarding in the right lower quadrant. Laboratory studies show a leukocyte count of 12,600/mm3. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Lymphatic tissue hyperplasia", "options": {"A": "Bacterial mesenteric lymphadenitis", "B": "Pseudomembranous plaque formation in the colon", "C": "Diverticular inflammation", "D": "Congenital anomaly of the omphalomesenteric duct", "E": "Lymphatic tissue hyperplasia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man presents to the emergency department with a headache, blurry vision, and abdominal pain. He states that his symptoms started several hours ago and have been gradually worsening. His temperature is 99.3°F (37.4°C), blood pressure is 222/128 mmHg, pulse is 87/min, respirations are 16/min, and oxygen saturation is 99% on room air. Physical exam is notable for an uncomfortable and distressed man. The patient is started on an esmolol and a nitroprusside drip thus lowering his blood pressure to 200/118 mmHg. The patient states that he feels better, but complains of feeling warm and flushed. An hour later, the patient seems confused and states his headache has resurfaced. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 138 mEq/L\nCl-: 101 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 17 mEq/L\nBUN: 31 mg/dL\nGlucose: 199 mg/dL\nCreatinine: 1.4 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the best treatment for this patient?", "answer": "Hydroxocobalamin", "options": {"A": "Amyl nitrite", "B": "Hydroxocobalamin", "C": "Insulin", "D": "IV fluids", "E": "Labetalol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 18-year-old man presents to his primary care physician with a complaint of excessive daytime sleepiness. He denies any substance abuse or major changes in his sleep schedule. He reports frequently dozing off during his regular daily activities. On further review of systems, he endorses falling asleep frequently with the uncomfortable sensation that there is someone in the room, even though he is alone. He also describes that from time to time, he has transient episodes of slurred speech when experiencing heartfelt laughter. Vital signs are stable, and his physical exam is unremarkable. This patient is likely deficient in a neurotransmitter produced in which part of the brain?", "answer": "Hypothalamus", "options": {"A": "Thalamus", "B": "Pons nucleus", "C": "Hippocampus", "D": "Hypothalamus", "E": "Midbrain"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old man presents to the primary care office with a recent history of frequent falls. He had been able to walk normally until about a year ago when he started noticing that both of his legs felt weak. He's also had some trouble with feeling in his feet. These 2 problems have caused multiple falls over the last year. On physical exam, he has notable leg and foot muscular atrophy and 4/5 strength throughout his bilateral lower extremities. Sensation to light touch and pinprick is absent up to the mid-calf. Ankle jerk reflex is absent bilaterally. A photo of the patient's foot is shown. Which of the following best describes the etiology of this patient's condition?", "answer": "Genetic", "options": {"A": "Autoimmune", "B": "Genetic", "C": "Ischemic", "D": "Infectious", "E": "Metabolic"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 60-year-old man is brought to the emergency department because of a 1-hour history of disorientation and slurred speech. He has a 10-year history of hypertension and hypercholesterolemia. His blood pressure is 210/110 mm Hg, and pulse is 90/min. Once the patient is stabilized, an MRI of the brain is performed, which shows an infarct of the left precentral gyrus involving the region that supplies the facial nerve. Given the MRI findings, which of the following neurological findings would most be expected?", "answer": "Flattening of the right nasolabial fold", "options": {"A": "Loss of taste in the posterior third of the right half of the tongue", "B": "Flattening of the right nasolabial fold", "C": "Decreased lacrimation of the left eye", "D": "Drooping of the left eyelid", "E": "Inability to raise the right eyebrow\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old boy presents to the pediatrician for a well child visit. He is meeting his developmental milestones and is in the 15th percentile for height and 70th percentile for weight. His parents report that he complains of fatiguing easily and having trouble participating in sports. They are concerned he is not getting enough sleep and state that sometimes they hear him snore. The patient has a past medical history of a supracondylar fracture of the humerus, which was appropriately treated. He is doing well in school but is sometimes bullied for being small. The patient eats a balanced diet of milk, fruit, and some vegetables. His parents have been trying to get him to drink more milk so he can grow taller. His temperature is 99.5°F (37.5°C), blood pressure is 90/48 mmHg, pulse is 100/min, respirations are 19/min, and oxygen saturation is 98% on room air. On physical exam, the patient appears well. HEENT exam is notable for conjunctival pallor and a unilateral clear middle ear effusion. Cardiac exam reveals a benign flow murmur. Pulmonary exam is clear to auscultation bilaterally. The patient's gait is stable and he is able to jump up and down. A full set of labs are ordered as requested by the parents including a serum vitamin D level, B12 level, and IGF level. A selection of these lab values are seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 9.9 mg/dL\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following would you expect to find in this patient?", "answer": "Increased RDW and TIBC", "options": {"A": "Decreased IGF levels", "B": "Decreased oxygen saturation when the patient sleeps", "C": "Decreased vitamin D level", "D": "Increased RDW and TIBC", "E": "Increased MCV"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old man is brought to the emergency department because of a knife wound to his back. His pulse is 110/min, respirations are 14/min, and blood pressure is 125/78 mm Hg. Examination shows a 5-cm deep stab wound at the level of T9. He withdraws the right foot to pain but is unable to sense vibration or whether his right toe is flexed or extended. Sensation in the left leg is normal. Motor strength is 5/5 in all extremities. Rectal tone is normal. Which of the following spinal column structures was most likely affected?", "answer": "Posterior spinal artery", "options": {"A": "Dorsal root", "B": "Posterior spinal artery", "C": "Central spinal cord grey matter", "D": "Lateral corticospinal tract", "E": "Artery of Adamkiewicz"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-year-old girl is brought to the physician because of a 2-hour history of severe epigastric pain, nausea, and vomiting. Her father has a history of similar episodes of abdominal pain and developed diabetes mellitus at the age of 30 years. Abdominal examination shows guarding and rigidity. Ultrasonography of the abdomen shows diffuse enlargement of the pancreas; no gallstones are visualized. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Premature activation of trypsinogen", "options": {"A": "Elevated serum amylase levels", "B": "Increased β-glucuronidase activity", "C": "Premature activation of trypsinogen", "D": "Defective elastase inhibitor", "E": "Impaired cellular copper transport"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old man is brought to your emergency department under arrest by the local police. The patient was found naked at a busy intersection jumping up and down on top of a car. Interviewing the patient, you discover that he has not slept in 2 days because he does not feel tired. He reports hearing voices. The patient was previously hospitalized 1 year ago with auditory hallucinations, paranoia, and a normal mood. What is the most likely diagnosis?", "answer": "Schizoaffective disorder", "options": {"A": "Schizophrenia", "B": "Schizotypal disorder", "C": "Schizoaffective disorder", "D": "Bipolar disorder", "E": "Unipolar mania"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought to the emergency department with an enlarged left knee. The patient’s parents state that his knee began to swell up a few hours ago while the family was indoors, watching TV. This has never happened before. The boy says his knee hurts when he puts weight on it. Past medical history is unremarkable. He was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Today, his vitals are normal for his age group with a blood pressure of 104/60 mm Hg, heart rate 90/min, respiratory rate 25/min, and temperature 37.1°C (98.8°F). On physical exam the child's left knee is indurated, erythematous, and painful to palpation. An ultrasound of the knee is consistent with hemarthrosis. A hematology workup is completed and the appropriate treatment was administered. Which of the following was the most likely treatment administered to this patient?", "answer": "Desmopressin", "options": {"A": "Fresh frozen plasma (FFP)", "B": "Cryoprecipitate", "C": "Desmopressin", "D": "vWF product", "E": "Factor IX replacement injections"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 69-year-old man is brought in by his wife with acute onset aphasia for the past 5 hours. The patient’s wife says that they were sitting having dinner when suddenly he was not able to speak. They delayed coming to the hospital because he had a similar episode 2 months ago which resolved within an hour. His past medical history is significant for hypercholesterolemia, managed with rosuvastatin, and a myocardial infarction (MI) 2 months ago, status post percutaneous transluminal coronary angioplasty complicated by residual angina. His family history is significant for his father who died of MI at age 60. The patient reports a 15-pack-year smoking history but denies any alcohol or recreational drug use. The vital signs include: temperature 37.0℃ (98.6℉), blood pressure 125/85 mm Hg, pulse 96/min, and respiratory rate 19/min. On physical examination, the patient has productive aphasia. There is a weakness of the right-sided lower facial muscles. The strength in his upper and lower extremities is 4/5 on the right and 5/5 on the left. There is also a decreased sensation on his right side. A noncontrast computed tomography (CT) scan of the head is unremarkable. CT angiography (CTA) and diffusion-weighted magnetic resonance imaging (MRI) of the brain are acquired, and the findings are shown in the exhibit (see image). Which of the following is the best course of treatment in this patient?", "answer": "Mechanical thrombectomy", "options": {"A": "IV tPA", "B": "Aspirin", "C": "Low molecular weight heparin", "D": "Mechanical thrombectomy", "E": "Mannitol"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old woman presents with a painful lesion in her mouth. She denies tooth pain, bleeding from the gums, nausea, vomiting, diarrhea, or previous episodes similar to this in the past. She states that her last normal menstrual period was 12 days ago, and she has not been sexually active since starting medical school 2 years ago. On physical examination, the patient has good dentition with no signs of infection with the exception of a solitary ulcerated lesion on the oral mucosa. The nonvesicular lesion has a clean gray-white base and is surrounded by erythema. Which of the following is correct concerning the most likely etiology of the oral lesion in this patient?", "answer": "This lesion is non-contagious but will most likely recur.", "options": {"A": "This lesion is due to a fungal infection and may mean you're immunocompromised.", "B": "This lesion is highly contagious and is due to reactivation of a dormant virus.", "C": "This lesion is associated with an autoimmune disease characterized by a sensitivity to gluten.", "D": "This lesion is non-contagious but will most likely recur.", "E": "This lesion may progress to squamous cell carcinoma."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old woman, gravida 1, para 1, comes to the physician for the evaluation of a painful mass in her left breast for several days. She has no fevers or chills. She has not noticed any changes in the right breast. She has no history of serious illness. Her last menstrual period was 3 weeks ago. She appears anxious. Her temperature is 37°C (98.6°F), pulse is 80/min, respirations are 13/min, and blood pressure is 130/75 mm Hg. Examination shows a palpable, mobile, tender mass in the left upper quadrant of the breast. Ultrasound shows a 1.75-cm, well-circumscribed anechoic mass with posterior acoustic enhancement. The patient says that she is very concerned that she may have breast cancer and wishes further diagnostic testing. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Fine needle aspiration", "options": {"A": "Fine needle aspiration", "B": "Mammogram", "C": "MRI scan of the left breast", "D": "Excisional biopsy", "E": "Core needle biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-month-old girl is brought to the pediatrician by her mother with a history of 3 episodes of breath-holding spells. The patient’s mother says that this is a new behavior and she is concerned. The patient was born at full term by spontaneous vaginal delivery with an uneventful perinatal period. She is also up to date on her vaccines. However, after the age of 6 months, the patient’s mother noticed that she was not as playful as other children of similar age. She is also not interested in interacting with others and her eye contact is poor. Her growth charts suggest that her weight, length, and head circumference were normal at birth, but there have been noticeable decelerations in weight and head circumference. On physical examination, her vital signs are normal. A neurologic examination reveals the presence of generalized mild hypotonia. She also makes repetitive hand wringing motions. Which of the following clinical features is most likely to develop in this patient during the next few years?", "answer": "Loss of purposeful use of her hands", "options": {"A": "Absence seizures", "B": "Hemiparesis", "C": "Intention tremor", "D": "Loss of purposeful use of her hands", "E": "Sensorineural deafness"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 43-year-old woman presents to the physician with the complaint of worsening fatigue over the past several months. She has found that she requires nearly double the amount of coffee consumption each day to stay awake at work and that despite maintaining a balanced, healthy diet, she has experienced significant weight gain. A blood test confirms the presence of anti-thyroid peroxidase antibodies. Which of the following additional findings would be consistent with her condition?", "answer": "Galactorrhea", "options": {"A": "Brisk deep tendon reflexes", "B": "Diarrhea", "C": "Galactorrhea", "D": "Heat intolerance", "E": "Proptosis of the globe"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 65-year-old woman comes to the physician because of a 3-month history of progressive shortness of breath and a dry cough. She has also noticed gradual development of facial discoloration. She has coronary artery disease, hypertension, and atrial fibrillation. She does not remember which medications she takes. Her temperature is 37°C (98.6°F), pulse is 90/min, respirations are 18/min, and blood pressure is 150/85 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 95%. Examination shows blue-gray discoloration of the face and both hands. Diffuse inspiratory crackles are heard. An x-ray of the chest shows reticular opacities around the lung periphery and particularly around the lung bases. The most likely cause of this patient's findings is an adverse effect to which of the following medications?", "answer": "Amiodarone", "options": {"A": "Procainamide", "B": "Lisinopril", "C": "Metoprolol", "D": "Amiodarone", "E": "Warfarin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 12-month-old boy is brought to the physician by his mother for a well-child examination. He was delivered at term after an uncomplicated pregnancy. His mother says he is breastfeeding well. He is at the 50th percentile for height and 65th percentile for weight. Physical examination shows no abnormalities. Urinalysis shows 3+ reducing substances. Compared to a healthy infant, giving this patient apple juice to drink will result in increased activity of which of the following enzymes?", "answer": "Hexokinase", "options": {"A": "Aldolase B", "B": "Galactokinase", "C": "Fructokinase", "D": "α-1,6-glucosidase", "E": "Hexokinase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 15-year-old girl presents with menorrhagia for the last 4 months. The patient’s mother says that she just started getting her period 4 months ago, which have been heavy and prolonged. The patient does recall getting a tooth extracted 3 years ago that was complicated by persistent bleeding afterward. She has no other significant past medical history and takes no current medications. Her vital signs include: blood pressure 118/76 mm Hg, respirations 17/min, pulse 64/min, temperature 36.7°C (98.0°F). Physical examination is unremarkable. Which of the following laboratory tests is most likely to be of the greatest diagnostic value in the workup of this patient?", "answer": "Partial thromboplastin time (PTT)", "options": {"A": "Factor IX assay", "B": "Partial thromboplastin time (PTT)", "C": "Anti-cardiolipin antibodies", "D": "Ro/La autoantibodies", "E": "Prothrombin time (PT)"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man comes to the physician because of a 2-month history of worsening shortness of breath with walking. He has not had any cough, fevers, or recent weight loss. He has hypercholesterolemia, for which he takes simvastatin, but otherwise is healthy. For 35 years he has worked for a demolition company. He has smoked 1 pack of cigarettes daily for the past 33 years. Pulmonary examination shows fine bibasilar end-expiratory crackles. An x-ray of the chest shows diffuse bilateral infiltrates predominantly in the lower lobes and bilateral calcified pleural plaques. The patient is most likely to develop which of the following conditions?", "answer": "Bronchogenic carcinoma\n\"", "options": {"A": "Thyroid carcinoma", "B": "Tuberculosis", "C": "Sarcoidosis", "D": "Mesothelioma", "E": "Bronchogenic carcinoma\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old woman comes to the physician because of painful paresthesias in her foot. Examination shows decreased sensation in the first interdigital space and a hallux valgus deformity. This patient's paresthesias are most likely caused by compression of which of the following nerves?", "answer": "Deep peroneal nerve", "options": {"A": "Superficial peroneal nerve", "B": "Deep peroneal nerve", "C": "Sural nerve", "D": "Saphenous nerve", "E": "Medial plantar nerve\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old male is brought to the emergency department by paramedics after being found down on the sidewalk. The paramedics are unable to provide any further history and the patient in unresponsive. On exam, the patient's vitals are: T: 36 deg C, HR: 65 bpm, BP: 100/66, RR: 4, SaO2: 96%. The emergency physician also observes the findings demonstrated in figures A and B. This patient most likely overdosed on which of the following?", "answer": "Heroin", "options": {"A": "Cocaine", "B": "Marijuana", "C": "Alcohol", "D": "Heroin", "E": "Phencyclidine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A retrospective study was conducted in a US county in order to determine the frequency of hypodontia (tooth agenesis), the most common craniofacial malformation in humans, as well as to assess the need for an interdisciplinary approach to managing subsequent functional and esthetic sequelae in a target population. Using a dental administration computer software tool, a total of 1498 patients who visited the outpatient clinic of a large specialist dental center between April 2017 and February 2018 were identified. The group comprised 766 women and 732 men. Hypodontia was found in 6.3% of the patients, a rate that was consistent with the average values found in the published medical literature. Which measure of frequency was used to describe the percentage of patients affected by hypodontia in this example?", "answer": "Period prevalence", "options": {"A": "Point prevalence", "B": "Period prevalence", "C": "Cumulative incidence", "D": "Incidence rate", "E": "Attack rate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A child is brought into the emergency room by her mother. Her mother states that the 7-year-old child was playing with their dog, who is up to date on his vaccinations. When the dog started playing more aggressively, the child suffered a bite on the hand with two puncture wounds from the dog's canines. The child is up-to-date on her vaccinations and has no medical history. Her vitals are within normal limits. If this bite becomes infected, what is the most likely organism to be the cause of infection?", "answer": "Pasteurella multocida", "options": {"A": "Clostridium perfringens", "B": "Pseudomonas aeruginosa", "C": "Pasteurella multocida", "D": "Clostridium tetani", "E": "Fusobacterium"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A previously healthy 4-year-old boy is brought to the physician because of a 2-day history of fever and swelling of the neck. His mother says that he has been increasingly weak over the past month. He takes no medications. His vaccination history is complete. His temperature is 39.5°C (103.1°F), blood pressure is 115/70 mm Hg, pulse is 94/min, and respiratory rate is 16/min. Palpation reveals bilateral cervical lymphadenopathy. There are several petechiae on the distal lower extremities and on the soft palate. The spleen is palpable 3 cm below the costal margin. Laboratory studies show:\nHemoglobin 8 g/dL\nLeukocyte 2400/mm3\nPlatelet 30,000/mm3\nA peripheral blood smear is shown. Which of the following best explains these findings?", "answer": "Acute lymphoid leukemia", "options": {"A": "Acute lymphoid leukemia", "B": "Bacterial sepsis", "C": "Burkitt’s lymphoma", "D": "Infectious mononucleosis", "E": "Aplastic anemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-month-old male infant is brought to the physician by his father because of swelling of his left hemiscrotum. He has otherwise been healthy and is gaining weight appropriately. Physical examination shows a nontender left scrotal mass that transilluminates. The mass increases in size when the boy cries but is easily reducible. Which of the following is the most likely underlying cause of this patient's findings?", "answer": "Patent processus vaginalis", "options": {"A": "Lack of testicular fixation", "B": "Germ cell neoplasia", "C": "Sperm collection in epididymal duct", "D": "Patent processus vaginalis", "E": "Dilation of pampiniform plexus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old woman presents to the family medical center with a 2-week history of a sore throat. She says that she has felt increasingly tired during the day and has a difficult time staying awake during her classes at the university. She appears well-nourished with a low energy level. Her vital signs include the following: the heart rate is 82/min, the respiratory rate is 14/min, the temperature is 37.8°C (100.0°F), and the blood pressure is 112/82 mm Hg. Inspection of the pharynx is depicted in the picture. Palpation of the neck reveals posterior cervical lymphadenopathy. The membrane does not bleed upon scraping. What is the most specific finding for detecting the syndrome described in the vignette?", "answer": "Positive monospot test", "options": {"A": "Positive monospot test", "B": "> 10% atypical lymphocytes", "C": "Positive rapid strep test", "D": "Increased transaminase levels", "E": "Growth in Loffler’s medium"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 64-year-old man is brought to the emergency department because of a 2-hour history of nausea, vomiting, and retrosternal pain that radiates to the back. Abdominal examination shows tenderness to palpation in the epigastric area. A CT scan of the patient's chest is shown. Which of the following is the most likely diagnosis?", "answer": "Esophageal rupture", "options": {"A": "Esophageal rupture", "B": "Pulmonary embolism", "C": "Pneumothorax", "D": "Mallory-Weiss syndrome", "E": "Aspiration pneumonia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the emergency department because of abdominal cramping, vomiting, and watery diarrhea for the past 4 hours. One day ago, she went to a seafood restaurant with her family to celebrate her birthday. Three of the attendees have developed similar symptoms. The patient appears lethargic. Her temperature is 38.8°C (101.8°F). Which of the following organisms is most likely responsible for this patient's current symptoms?", "answer": "Vibrio parahaemolyticus", "options": {"A": "Campylobacter jejuni", "B": "Staphylococcus aureus", "C": "Vibrio parahaemolyticus", "D": "Listeria monocytogenes", "E": "Salmonella enterica"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman comes to the physician because of recurrent episodes of reddish discoloration of her urine. She also has a 3-month history of intermittent abdominal pain, yellowish discoloration of the skin and eyes, and fatigue. Physical examination shows pallor and scleral icterus. The spleen is not palpable. Her hemoglobin concentration is 7.8 g/dL, leukocyte count is 2,000/mm3, and platelet count is 80,000/mm3. Serum LDH and unconjugated bilirubin concentrations are elevated. Addition of a serum containing anti-human globulins to a blood sample shows no agglutination. A urine dipstick shows blood; urinalysis shows no RBCs. A CT scan of the abdomen shows a thrombus in a distal branch of the superior mesenteric vein. Which of the following is the most likely cause of this patient's condition?", "answer": "Absence of protective factors against destruction by complement", "options": {"A": "Activation and consumption of platelets and coagulation factors", "B": "Endothelial cell dysfunction from bacterial toxin production", "C": "Absence of protective factors against destruction by complement", "D": "Formation of IgG antibodies against glycoprotein IIb/IIIa", "E": "Replacement of a single amino acid in a β-globin chain\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old male presents to the emergency department with facial swelling and trouble breathing. These symptoms began this morning and progressively worsened over the past several hours. Vital signs are as follows: T 37.7, HR 108, BP 120/76, RR 20, and SpO2 96%. Physical examination reveals nonpitting swelling of the face, hands, and arms as well as edema of the tongue and mucus membranes of the mouth and pharynx. The patient reports several episodes of mild facial swelling that occurred during childhood between the ages of 5-18, but he does not recall seeing a physician or receiving treatment for this. His medical history is otherwise negative, except for mild hypertension for which his primary care physician initiated lisinopril 2 weeks ago. This patient most likely has which of the following underlying abnormalities?", "answer": "Deficiency of C1 esterase inhibitor", "options": {"A": "MHC class I deficiency", "B": "Defective lysosomal storage proteins", "C": "Lack of NADPH oxidase", "D": "Defect in cytoskeletal glycoprotein", "E": "Deficiency of C1 esterase inhibitor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old man comes to the emergency department with palpitations, sweating, and shortness of breath that began 10 minutes ago. He says, “Please help me, I don't want to die.” He has experienced several similar episodes over the past 2 months, which occurred without warning in situations including open spaces or crowds and resolved gradually after 5 to 10 minutes. He has been staying at home as much as possible out of fear of triggering another episode. He has no history of serious illness and takes no medications. He drinks 3 bottles of beer daily. He appears anxious and has a flushed face. His pulse is 104/min, respirations are 12/min, and blood pressure is 135/82 mm Hg. Cardiopulmonary examination shows no abnormalities. An ECG shows sinus tachycardia. Which of the following is the most appropriate initial step in management?", "answer": "Oral alprazolam", "options": {"A": "Oral propranolol", "B": "Oral buspirone", "C": "Oral alprazolam", "D": "Oral venlafaxine", "E": "Long-term ECG monitoring"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 22-year-old man presents to a physician with a single painless ulcer on his glans penis that he first noticed 2 weeks ago. He mentions that he is sexually active with multiple partners. There is no history of fevers. Initially, he thought that the ulcer would go away on its own, but decided to come to the clinic because the ulcer persisted. On palpation of the ulcer, the edge and base are indurated. There is no purulence. Multiple painless, firm, and non-fixed lymph nodes are present in the inguinal regions bilaterally. The physician orders a Venereal Disease Research Laboratory (VDRL) test, which is positive. The Treponema pallidum particle agglutination assay is also positive. Upon discussing the diagnosis, the patient informs the physician that he has a severe allergy to penicillin and he declines treatment with an injectable medicine. Which of the following drugs is most appropriate for this patient?", "answer": "Azithromycin", "options": {"A": "Azithromycin", "B": "Chloramphenicol", "C": "Ciprofloxacin", "D": "Metronidazole", "E": "Trimethoprim-sulfamethoxazole"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-year-old girl with an aortic stenosis correction comes to the office for a follow-up visit for acute lymphoblastic lymphoma. She initiated chemotherapy a week before through a peripherally inserted central line. She reports being ‘tired all the time’ and has been bruising easily. Her vital signs are within normal limits. Physical examination shows several tenders, non-blanching petechiae on the pads of the fingers and toes; several dark, non-tender petechiae on her palms and soles; and small, linear hemorrhages under her fingernails. Fundoscopic examination shows various small areas of hemorrhage on the retinae bilaterally. Cardiac examination is notable for a II/VI systolic ejection murmur that seems to have worsened in comparison to the last visit. Which of the following is the most likely cause?", "answer": "Infective endocarditis", "options": {"A": "Acute rheumatic fever", "B": "Bleeding diathesis secondary to thrombocytopenia", "C": "Dilated cardiomyopathy", "D": "Hypertrophic cardiomyopathy", "E": "Infective endocarditis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old pregnant woman, G4 P3, visits your office at week 30 of gestation. She is very excited about her pregnancy and wants to be the healthiest she can be in preparation for labor and for her baby. What vaccination should she receive at this visit?", "answer": "Tetanus, diphtheria, and acellular pertussis (Tdap)", "options": {"A": "Live attenuated influenza vaccine", "B": "Tetanus, diphtheria, and acellular pertussis (Tdap)", "C": "Varicella vaccine", "D": "Herpes zoster vaccine", "E": "Measles, mumps, and rubella (MMR)"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old Caucasian male presents to your office with hemoptysis and hematuria. On physical exam you note a saddle nose deformity. Laboratory results show an elevated level of cytoplasmic antineutrophil cytoplasmic antibody. Which of the following interventions is most appropriate for this patient?", "answer": "Corticosteroids", "options": {"A": "Smoking cessation", "B": "IV immunoglobulin", "C": "Corticosteroids", "D": "Isoniazid", "E": "Discontinuation of ibuprofen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 54-year-old man is brought to the emergency department 1 hour after the sudden onset of shortness of breath, severe chest pain, and sweating. He has hypertension and type 2 diabetes mellitus. He has smoked one pack and a half of cigarettes daily for 20 years. An ECG shows ST-segment elevations in leads II, III, and avF. The next hospital with a cardiac catheterization unit is more than 2 hours away. Reperfusion pharmacotherapy is initiated. Which of the following is the primary mechanism of action of this medication?", "answer": "Conversion of plasminogen to plasmin", "options": {"A": "Blocking of adenosine diphosphate receptors", "B": "Conversion of plasminogen to plasmin", "C": "Prevention of thromboxane formation", "D": "Inhibition of glutamic acid residue carboxylation", "E": "Direct inhibition of thrombin activity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man presents to the outpatient clinic for a routine health checkup. He recently lost his hearing completely in both ears and has occasional flare-ups of osteoarthritis in his hands and hips. He is a non-diabetic and hypertensive for the past 25 years. His brother recently died due to prostate cancer. His current blood pressure is 126/84 mm Hg. His cholesterol and PSA levels are within normal limits. The flexible sigmoidoscopy along with stool guaiac test is negative. The serum calcium, phosphorus concentrations and liver function test results are within normal limits. However, the ALP levels are increased by more than thrice the upper limit. Radiography of the axial skeleton reveals cortical thickening. What is the most likely diagnosis?", "answer": "Paget's disease of the bone", "options": {"A": "Osteomalacia", "B": "Paget's disease of the bone", "C": "Metastatic bone disease", "D": "Plasmacytoma", "E": "Primary hyperparathyroidism"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old man is brought to the emergency room after suffering a catastrophic fall while skiing during a training session. He was found unconscious by the aeromedical emergency services team, who established an airway and cervical spine control measures. Upon arrival at the emergency department, ventilatory support is started followed by an evaluation of the patient by the neurosurgical team. His blood pressure is 210/125 mm Hg, the heart rate is 55/min, and the respiratory rate is 15/min with a Cheyne-Stokes breathing pattern. Neurological examination shows a Glasgow Coma Score of 4/15, with dilated, fixed pupils and a decerebrate posture. An MRI of the brain shows diffuse axonal injury to the brain with severe cerebral edema, multiple frontal and occipital lobe contusions and multiple flame-shaped hemorrhages in the brainstem. Despite the medical team efforts, the patient dies 24 hours later. What would be the most likely type of herniation found at this patient’s autopsy?", "answer": "Central herniation", "options": {"A": "Uncal herniation", "B": "Subfalcine herniation", "C": "Central herniation", "D": "Downward cerebellar herniation", "E": "Upward cerebellar herniation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 11-year-old boy with Burkitt lymphoma is brought to the emergency department because of nausea, vomiting, flank pain, and dark urine for 1 day. Two days ago, he began induction chemotherapy with cyclophosphamide, vincristine, prednisolone, and doxorubicin. Urinalysis shows 3+ blood and abundant amber-colored, rhomboid crystals. Which of the following is most likely to have been effective in preventing this patient’s symptoms?", "answer": "Alkalinization of the urine", "options": {"A": "Water restriction", "B": "Administration of ceftriaxone", "C": "Alkalinization of the urine", "D": "Administration of probenecid", "E": "Administration of hydrochlorothiazide\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old male with a history significant for IV drug use comes to the emergency department complaining of persistent fatigue and malaise for the past three weeks. On physical exam, you observe a lethargic male with icteric sclera and hepatomegaly. AST and ALT are elevated at 600 and 750, respectively. HCV RNA is positive. Albumin is 3.8 g/dL and PT is 12. A liver biopsy shows significant inflammation with bridging fibrosis. What is the most appropriate treatment at this time?", "answer": "Combined interferon and ribavirin", "options": {"A": "Interferon", "B": "Ribavirin", "C": "Lamivudine", "D": "Combined interferon and ribavirin", "E": "Combined interferon and lamivudine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 41-year-old woman comes to the doctor because of gradually progressive weakness in her right hand over the past few weeks. She goes to the gym to lift weights 5 times a week. With the dorsum of the right hand on a flat surface, the patient is unable to move her thumb to touch a pen held 2 cm above the interphalangeal joint of the thumb. An MRI of the right arm shows compression of a nerve that passes through the pronator teres muscle. Based on the examination findings, loss of innervation of which of the following muscles is most likely in this patient?", "answer": "Abductor pollicis brevis", "options": {"A": "Adductor pollicis", "B": "Flexor pollicis longus", "C": "First dorsal interosseus", "D": "Abductor pollicis brevis", "E": "Opponens pollicis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old woman presents to the emergency department because she started experiencing dyspnea and urticaria after dinner. Her symptoms began approximately 15 minutes after eating a new type of shellfish that she has never had before. On physical exam her breathing is labored, and pulmonary auscultation reveals wheezing bilaterally. Given this presentation, she is immediately started on intramuscular epinephrine for treatment of her symptoms. If part of this patient's symptoms were related to the systemic release of certain complement components, which of the following is another function of the responsible component?", "answer": "Chemotaxis", "options": {"A": "Chemotaxis", "B": "Clearance of immune complexes", "C": "Direct cytolysis", "D": "Inhibition of kallikrein activation", "E": "Opsonization of pathogens"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 8-year-old boy is brought to the physician by his mother because of 6 months of progressive fatigue and weight loss. His mother reports that during this time, he has had decreased energy and has become a “picky eater.” He often has loose stools and complains of occasional abdominal pain and nausea. His family moved to a different house 7 months ago. He is at the 50th percentile for height and 25th percentile for weight. His temperature is 36.7°C (98°F), pulse is 116/min, and blood pressure is 85/46 mm Hg. Physical examination shows tanned skin and bluish-black gums. The abdomen is soft, nondistended, and nontender. Serum studies show:\nNa+ 134 mEq/L\nK+ 5.4 mEq/L\nCl- 104 mEq/L\nBicarbonate 21 mEq/L\nUrea nitrogen 16 mg/dL\nCreatinine 0.9 mg/dL\nGlucose 70 mg/dL\nIntravenous fluid resuscitation is begun. Which of the following is the most appropriate initial step in treatment?\"", "answer": "Glucocorticoids", "options": {"A": "Levothyroxine", "B": "Fluoxetine", "C": "Glucocorticoids", "D": "Hyperbaric oxygen", "E": "Deferoxamine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 10-year-old girl presents to your office with a fever and rash. Her mother first noticed the rash 2 days ago after a camping trip. The rash began on her wrists and ankles and has now spread to her palms and the soles of her feet. This morning, she was feeling unwell and complaining of a headache. She had a fever of 102°F (39°C) prompting her mother to bring her to your office. She is otherwise healthy and does not take any medications. Her medical history is significant for a broken arm at age 8. On physical exam her blood pressure is 120/80 mmHg, pulse is 110/min, and respirations are 22/min. You notice a petechial rash on the palms, soles, ankles, and wrists. Which of the following findings would confirm the most likely cause of this patient's symptoms?", "answer": "Cross-reactivity of serum with proteus antigens", "options": {"A": "Granulocytes with morulae in the cytoplasm", "B": "Cross-reactivity of serum with proteus antigens", "C": "Monocytes with morulae in the cytoplasm", "D": "Positive fluorescent treponemal antibody absorption test (FTA-ABS)", "E": "Positive Borrelia burgdorferi antibodies"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old man suffered an anterior wall myocardial infarction that was managed in the cath lab with emergent coronary stenting and revascularization. The patient states that his wife, adult children, and cousins may be disclosed information regarding his care and health information. The patient has been progressing well without any further complications since his initial catheterization. On hospital day #3, a woman stops you in the hall outside of the patient's room whom you recognize as the patient's cousin. She asks you about the patient's prognosis and how the patient is progressing after his heart attack. Which of the following is the most appropriate next step?", "answer": "Discuss the patient's hospital course and expected prognosis with the woman", "options": {"A": "Direct the woman to discuss these issues with the patient himself", "B": "Discuss the patient's hospital course and expected prognosis with the woman", "C": "Ask for identification confirming that the woman is truly the patient's cousin", "D": "Decline to comment per HIPAA patient confidentiality regulations", "E": "Ask the patient if it is acceptable to share information with this individual"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An otherwise healthy 28-year-old primigravid woman at 30 weeks' gestation comes to the physician with a 5-day history of epigastric pain and nausea that is worse at night. Two years ago, she was diagnosed with a peptic ulcer and was treated with a proton pump inhibitor and antibiotics. Medications include folic acid and a multivitamin. Her pulse is 90/min and blood pressure is 130/85 mm Hg. Pelvic examination shows a uterus consistent in size with a 30-week gestation. Laboratory studies show:\nHemoglobin 8.6 g/dL\nPlatelet count 95,000/mm3\nSerum\nTotal bilirubin 1.5 mg/dL\nAspartate aminotransferase 80 U/L\nLactate dehydrogenase 705 U/L\nUrine\npH 6.2\nProtein 2+\nWBC negative\nBacteria occasional\nNitrates negative\nWhich of the following best explains this patient's symptoms?\"", "answer": "Stretching of Glisson capsule", "options": {"A": "Inflammation of the gall bladder", "B": "Bacterial infection of the kidney", "C": "Inflammation of the lower esophageal mucosa", "D": "Stretching of Glisson capsule", "E": "Acute inflammation of the pancreas"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 54-year-old man is brought to the emergency department because of progressive tingling and weakness in both of his legs for the past two days. The patient reports that his symptoms interfere with his ability to walk. Two weeks ago, he had an upper respiratory tract infection, which resolved spontaneously. His vital signs are within normal limits. Examination shows weakness in the lower extremities with absent deep tendon reflexes. Reflexes are 1+ in the upper extremities. Sensation to pinprick and light touch is intact. Romberg's test is negative. Laboratory studies show a leukocyte count of 12,000/mm3. Cerebrospinal fluid analysis results show:\nOpening pressure normal\nProtein 200 mg/dL\nGlucose 70 mg/dL\nWhite blood cells 4/mm3\nThis patient is at increased risk for which of the following conditions?\"", "answer": "Respiratory failure", "options": {"A": "Dementia", "B": "Thymoma", "C": "Urinary incontinence", "D": "Respiratory failure", "E": "Hypertrophic cardiomyopathy\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 44-year-old man comes to the physician because of a 3-week history of productive cough, fever, and lethargy. He also has several skin lesions over his body. His symptoms began 3 weeks after he returned from a camping trip in Kentucky. Three years ago, he underwent kidney transplantation for polycystic kidney disease. Current medications include sirolimus and prednisone. His temperature is 38°C (100.4°F). Diffuse crackles are heard over the lung fields. There are 4 white, verrucous skin patches over his chest and upper limbs. A photomicrograph of a skin biopsy specimen from one of the lesions is shown. Which of the following is the most likely diagnosis?", "answer": "Blastomycosis", "options": {"A": "Histoplasmosis", "B": "Mucormycosis", "C": "Coccidioidomycosis", "D": "Cryptococcosis", "E": "Blastomycosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old woman presents for a routine wellness checkup. She complains of general fatigue and lethargy for the past 6 months. She does not have a significant past medical history and is currently not taking any medications. The patient reports that she drinks “socially” approx. 6 nights a week. She says she also enjoys a “nightcap,” which is 1–2 glasses of wine before bed every night. She denies any history of drug use or smoking. The patient is afebrile, and her vital signs are within normal limits. A physical examination reveals pallor of the mucous membranes. Her laboratory findings are significant for a mean corpuscular volume of 72 fL, leukocyte count of 5,300/mL, hemoglobin of 11.0 g/dL, and platelet count of 420,000/mL.\nWhich of the following is the most likely cause of this patient’s thrombocytosis?", "answer": "Iron deficiency anemia", "options": {"A": "Iron deficiency anemia", "B": "Chronic alcohol abuse", "C": "Chronic myelogenous leukemia (CML)", "D": "Aplastic anemia", "E": "Essential thrombocytosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 39-year-old male is rushed to the emergency department after he developed a sudden-onset severe headache with ensuing nausea, vomiting, vision changes, and loss of consciousness. Past medical history is unattainable. He reports that the headache is worse than any he has experienced before. Noncontrast CT of the head is significant for an intracranial hemorrhage. Follow-up cerebral angiography is performed and shows a ruptured anterior communicating artery aneurysm. Which of the following has the strongest association with this patient's current presentation?", "answer": "Kidney ultrasound showing numerous bilateral renal cysts", "options": {"A": "History of multiple hemangioblastomas of the retina and spine as well as pheochromocytoma", "B": "Brain MRI showing a butterfly glioma with a central necrotic core", "C": "Abdominal CT suggestive of renal cell carcinoma", "D": "Kidney ultrasound showing numerous bilateral renal cysts", "E": "History of renal transplantation at 8 years of age"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 15-year-old girl comes to the physician for a well-child examination. She feels well. Her father has coronary artery disease and hypertension. Her mother has type 2 diabetes mellitus, hypercholesterolemia, and had a myocardial infarction at the age of 52 years. She is at the 25th percentile for height and above the 95th percentile for weight. Her BMI is 32 kg/m2. Her temperature is 37°C (98.6°F), pulse is 99/min, and blood pressure is 140/88 mm Hg. Physical examination shows no abnormalities. Random serum studies show:\nGlucose 160 mg/dL\nCreatinine 0.8 mg/dL\nTotal cholesterol 212 mg/dL\nHDL-cholesterol 32 mg/dL\nLDL-cholesterol 134 mg/dL\nTriglycerides 230 mg/dL\nIn addition to regular aerobic physical activity, which of the following is the most appropriate next step in management?\"", "answer": "Reduced-calorie diet", "options": {"A": "Niacin therapy", "B": "Reduced-calorie diet", "C": "Fenofibrate therapy", "D": "Atorvastatin therapy", "E": "Metformin therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old woman who is an established patient presents to your office. She is complaining of increased urination and increased thirst. She has recently began taking several over-the-counter vitamins and supplements. On further review, she reports she has also been having abdominal pain and constipation. She denies significant weight changes. Her fingerstick blood glucose in your office is 96 mg/dL.\n\nWhich of the following test is most likely to provide the diagnosis?", "answer": "Calcium level", "options": {"A": "Pyridoxine levels", "B": "Niacin levels", "C": "Calcium level", "D": "Hemoglobin A1C", "E": "Free T4 levels"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 9-year-old boy is brought to his primary care physician after his mom noticed that he was limping. He says that he has been experiencing significant hip and knee pain over the last 2 months but thought he may have just strained a muscle. Radiographs show a collapse of the femoral head, and he is diagnosed with Legg-Calve-Perthes disease. He undergoes surgery and is placed in a Petrie cast from his hips to his toes bilaterally so that he is unable to move his knees or ankles. Eight weeks later, the cast is removed, and he is found to have significantly smaller calves than before the cast was placed. Which process in myocytes is most likely responsible for this finding?", "answer": "Polyubiquitination of proteins", "options": {"A": "Decreased formation of double membrane bound vesicles", "B": "Increased formation of double membrane bound vesicles", "C": "Inhibition of gene transcription", "D": "Monoubiquitination of proteins", "E": "Polyubiquitination of proteins"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old African American G1P0010 presents to her gynecologist for an annual visit. She has a medical history of hypertension, for which she takes hydrochlorothiazide. The patient’s mother had breast cancer at age 68, and her sister has endometriosis. At this visit, the patient’s temperature is 98.6°F (37.0°C), blood pressure is 138/74 mmHg, pulse is 80/min, and respirations are 13/min. Her BMI is 32.4 kg/m^2. Pelvic exam reveals a nontender, 16-week sized uterus with an irregular contour. A transvaginal ultrasound is performed and demonstrates a submucosal leiomyoma. This patient is at most increased risk of which of the following complications?", "answer": "Iron deficiency anemia", "options": {"A": "Infertility", "B": "Uterine prolapse", "C": "Endometrial cancer", "D": "Miscarriage", "E": "Iron deficiency anemia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old previously healthy woman with no other past medical history is post-operative day one from an open reduction and internal fixation of a fractured right radius and ulna after a motor vehicle accident. What is one of the primary ways of preventing postoperative pneumonia in this patient?", "answer": "Incentive spirometry", "options": {"A": "In-hospital intravenous antibiotics", "B": "Outpatient oral antibiotics", "C": "Hyperbaric oxygenation", "D": "Incentive spirometry", "E": "Shallow breathing exercises"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old gravida-2-para-1 at 12 weeks gestation presents for a prenatal visit. Over the past week, she has felt increasingly tired, even after waking up in the morning. She is vegan and avoids all animal products. She was diagnosed with Graves’ disease 6 months ago. Before conception, methimazole was switched to propylthiouracil (PTU). Other medications include folic acid and a multivitamin. The vital signs include: temperature 37.1℃ (98.8℉), pulse 72/min, respiratory rate 12/min, and blood pressure 110/75 mm Hg. The conjunctivae and nail beds are pale. Petechiae are present over the distal lower extremities. The pelvic examination reveals a uterus consistent in size with a 12-week gestation. Examination of the neck, lungs, heart, and abdomen shows no abnormalities. The laboratory studies show the following:\nLaboratory test\nHemoglobin 9.0 g/dL\nMean corpuscular volume 90 μm3\nLeukocyte count 4,000/mm3\nSegmented neutrophils 55%\nLymphocytes 40%\nPlatelet count 110,000/mm3\nSerum\nThyroid-stimulating hormone 0.1 μU/mL\nThyroxine (T-4) 8 μg/dL\nLactate dehydrogenase 60 U/L\nTotal bilirubin 0.5 mg/dL\nIron 100 μg/dL\nFerritin 110 ng/mL\nTotal iron-binding capacity 250 μg/dL\nWhich of the following best explains these findings?", "answer": "Drug-induced marrow failure", "options": {"A": "Autoimmune hemolysis", "B": "Drug-induced marrow failure", "C": "Hemodilution of pregnancy", "D": "Excess antithyroid medication", "E": "Vitamin B12 deficiency"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 29-year-old man comes to the physician for a routine health maintenance examination. He has no history of serious illness. His mother has hypertension and his father died of testicular cancer at the age of 51 years. He does not smoke or drink. He is sexually active and uses condoms consistently. He takes no medications. His immunization records are unavailable. He works as a financial consultant and will go on a business trip to Mexico City in 2 weeks. His temperature is 36.7°C (98.7° F), pulse is 78/min, and blood pressure is 122/78 mm Hg. Cardiopulmonary examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13.4 g/dL\nLeukocyte count 9800/mm3\nPlatelet count 168,000/mm3\nSerum\nGlucose 113 mg/dL\nCreatinine 1.1 mg/dL\nWhich of the following recommendations is most appropriate at this time?\"", "answer": "Hepatitis A vaccine", "options": {"A": "Malaria chemoprophylaxis", "B": "Rabies vaccine", "C": "Cholera vaccine", "D": "Yellow fever vaccine", "E": "Hepatitis A vaccine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 39-year-old woman seeks evaluation from her gynecologist due to recent changes in her menstrual cycle. Her last menstrual period was greater than 12 months ago. She has 2 children and had regular menstrual periods in the past. She also complains of difficulty in falling and staying asleep, occasional hot flashes, vaginal dryness, and decreased libido. The physical examination is unremarkable, and the height and weight are 1.68 m (5 ft 6 in) and 70 kg (154 lb), respectively. She has the following hormonal panel from 2 months ago when she first sought help for her symptoms.\nHormonal panel results  \nHuman Chorionic Gonadotropin 4 IU/L (0.8 - 7.3 IU/L)\nThyroid Stimulating Hormone 2.5 mIU/L (0.4 - 4.2 mIU/L)\nProlactin 5 ng/mL (2-29 ng/mL)\nFollicle Stimulating Hormone 45 mIU/mL (Follicular phase: 3.1-7.9 mIU/mL; Ovulation peak: 2.3-18.5 mIU/mL; Luteal phase: 1.4-5.5 mIU/mL)\nEstradiol 5 pg/mL (Mid-follicular phase: 27-123 pg/mL; Periovulatory: 96-436 pg/mL; Mid-luteal phase: 49-294 pg/mL)\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Primary ovarian insufficiency (POI)", "options": {"A": "Polycystic ovary syndrome (PCOS)", "B": "Breast cancer", "C": "Pituitary adenoma", "D": "Hyperthyroidism", "E": "Primary ovarian insufficiency (POI)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old female was found upon mammography to have branching calcifications in the right lower breast. Physical exam revealed a palpable nodularity in the same location. A tissue biopsy was taken from the lesion, and the pathology report diagnosed the lesion as comedocarcinoma. Which of the following histological findings is most likely present in the lesion?", "answer": "Pleomorphic cells surrounding areas of caseous necrosis", "options": {"A": "Orderly rows of cells surrounding lobules", "B": "Disordered glandular cells invading the ductal basement membrane", "C": "Extensive lymphocytic infiltrate", "D": "Halo cells in epidermal tissue", "E": "Pleomorphic cells surrounding areas of caseous necrosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-year-old male presents to the pediatrician with seizures. His mother reports that the patient has had two seizures lasting about 30 seconds each over the last three days. She reports that the patient has previously had seizures a few times per year since he was 12 months of age. The patient’s past medical history is otherwise notable for intellectual disability. He rolled over at 14 months of age and walked at 24 months of age. The patient’s mother denies any family history of epilepsy or other neurologic diseases. The patient is in the 3rd percentile for height and the 15th percentile for weight. On physical exam, he has a happy demeanor with frequent smiling. The patient has strabismus and an ataxic gait accompanied by flapping of the hands. He responds intermittently to questions with one-word answers. This patient is most likely to have which of the following genetic abnormalities?", "answer": "Paternal uniparental disomy of chromosome 15", "options": {"A": "Chromosomal macrodeletion on chromosome 5", "B": "Imprinting defect on chromosome 11", "C": "Maternal uniparental disomy of chromosome 15", "D": "Paternal uniparental disomy of chromosome 15", "E": "Trinucleotide repeat disorder"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old woman comes to the physician for the evaluation of progressive loss of vision in her left eye and gradual blurring of vision in her right eye over the past 2 months. She also says that she has had occasional headaches and has noticed a decrease in her sense of smell lately. The patient's only medication is fexofenadine for seasonal allergies. She is 158 cm (5 ft 2 in) tall and weighs 61 kg (135 lbs); BMI is 24.7 kg/m2. Vital signs are within normal limits. Visual acuity is 20/40 in the right eye and there is minimal light perception in the left eye. In the swinging flashlight test, both of her eyes dilate as the light moves from the right to left eye. Fundoscopy shows papilledema in the right optic disc and a pale left optic disc. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Meningioma", "options": {"A": "Hereditary optic neuropathy", "B": "Pseudotumor cerebri", "C": "Anterior ischemic optic neuropathy", "D": "Meningioma", "E": "Multiple sclerosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old man presents to his primary care physician for a general checkup. The patient is a healthy young man with no significant past medical history. He is a MD/PhD student and lives in New York City. He exercises frequently and is doing very well in school. He is currently sexually active with multiple female partners and does not use protection. His temperature is 98.9°F (37.2°C), blood pressure is 147/98 mmHg, pulse is 90/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is notable for a very muscular young man. The patient has comedonal acne and palpable breast tissue. Testicular exam reveals small and symmetrical testicles. Which of the following laboratory changes is most likely to be found in this patient?", "answer": "Decreased GnRH", "options": {"A": "Decreased bone density", "B": "Decreased GnRH", "C": "Decreased LDL", "D": "Increased HDL", "E": "Increased sperm count"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man presents to the physician with blood in his sputum for 3 days. He also mentions that he has had a cough for the last 3 months but thought that it was because of the winter season. He also has often experienced fatigue recently. His temperature is 37.0°C (98.6°F), the respiratory rate is 15/min, the pulse is 67/min, and the blood pressure is 122/98 mm Hg. Auscultation of his chest reveals normal heart sounds but localized rhonchi over the right infrascapular region. A detailed diagnostic evaluation including a complete blood count and other serum biochemistry, chest radiogram, computed tomography of chest and abdomen, magnetic resonance imaging of the brain, bone scan, and pulmonary function tests are ordered, which confirm a diagnosis of limited-disease small cell lung cancer of 2.5 cm (1 in) in diameter, located in the lower lobe of the right lung, with the involvement of ipsilateral hilar lymph nodes and intrapulmonary lymph nodes. The mediastinal, subcarinal, scalene or supraclavicular lymph nodes are not involved, and there is no distant metastasis. There is no additional comorbidity and his performance status is good. The patient does not have any contraindication to any chemotherapeutic agents or radiotherapy. Which of the following is the best treatment option for this patient?", "answer": "Platinum-based chemotherapy plus etoposide and thoracic radiation therapy", "options": {"A": "Lobectomy with adjuvant topotecan-based chemotherapy", "B": "Pneumonectomy with adjuvant platinum-based chemotherapy and thoracic radiation therapy", "C": "Platinum-based chemotherapy plus etoposide and thoracic radiation therapy", "D": "Topotecan-based chemotherapy plus thoracic radiation therapy", "E": "Thoracic radiation therapy followed by prophylactic cranial irradiation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old man is brought to a psychiatric hospital by friends for erratic behavior. He has been up for the past several nights painting his apartment walls purple and reading the Bible out loud, as well as talking fast and making sexually provocative comments. Collateral information from family reveals 2 similar episodes last year. Mental status exam is notable for labile affect and grandiose delusions. Urine toxicology is negative. The patient is admitted and started on lithium for mania. His symptoms resolve within 2 weeks. How should this patient’s lithium be managed in anticipation of discharge?", "answer": "Continue lithium lifelong", "options": {"A": "Continue lithium lifelong", "B": "Continue lithium until a therapeutic serum lithium level is reached, then taper it", "C": "Cross-taper lithium to aripiprazole for maintenance therapy", "D": "Cross-taper lithium to valproic acid for maintenance therapy", "E": "Discontinue lithium, but re-start in the future if the patient has another manic episode"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 70-year-old man comes to the physician for a follow-up examination of diffuse exertional chest pain which he has successfully been treating with sublingual nitroglycerin for the past year. The patient has been taking lisinopril daily for essential hypertension. His pulse is 75/min and regular, and blood pressure is 155/90 mm Hg. Cardiac and pulmonary examination show no abnormalities; there is no peripheral edema. A decrease of which of the following is the most likely explanation for the improvement of this patient's chest pain?", "answer": "End-diastolic pressure", "options": {"A": "Ventricular compliance", "B": "Peripheral arterial resistance", "C": "Electrical conduction speed", "D": "Venous pooling", "E": "End-diastolic pressure"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 78-year-old woman living in New Jersey is brought to the emergency department in July with a fever for 5 days. Lethargy is present. She has had bloody urine over the last 48 hours but denies any nausea, vomiting, or abdominal pain. She has no history of serious illness and takes no medications. She has not traveled anywhere outside her city for the past several years. She appears ill. The temperature is 40.8℃ (105.4℉), the pulse is 108/min, the respiration rate is 20/min, and the blood pressure is 105/50 mm Hg. The abdominal exam reveals hepatosplenomegaly. Lymphadenopathy is absent. Petechiae are seen on the lower extremities. Laboratory studies show the following:\nLaboratory test\nHemoglobin 8 g/dL\nMean corpuscular volume (MCV) 98 µm3\nLeukocyte count 4,200/mm3\nSegmented neutrophils 32%\nLymphocytes 58%\nPlatelet count 108,000/mm3\nBilirubin, total 5.0 mg/dL\nDirect 0.7 mg/dL\nAspartate aminotransferase (AST) 51 U/L\nAlanine aminotransferase (ALT) 56 U/L\nAlkaline phosphatase 180 U/L\nLactate dehydrogenase (LDH) 640 U/L (N = 140–280 U/L)\nHaptoglobin 20 mg/dL (N = 30–200 mg/dL)\nUrine\nHemoglobin +\nUrobilinogen +\nProtein +\nA peripheral blood smear is shown (see image). Which of the following is the most likely diagnosis?", "answer": "Babesiosis", "options": {"A": "Babesiosis", "B": "Lyme disease", "C": "Malaria", "D": "Plague", "E": "Leishmaniasis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old woman is referred to a reproduction specialist because of an inability to conceive. She comes with her husband, who was previously examined for causes of male infertility, but was shown to be healthy. The patient has a history of 2 pregnancies at the age of 15 and 17, which were both terminated in the first trimester. She had menarche at the age of 11, and her menstrual cycles began to be regular at the age of 13. Her menses are now regular, but painful and heavy. Occasionally, she notes a mild pain in the lower left quadrant of her abdomen. Her past medical history is also significant for episodes of depression, but she currently denies any depressive symptoms. Current medications are sertraline daily and cognitive-behavioral therapy twice a week. After reviewing her history, the doctor suggests performing an exploratory laparoscopy with salpingoscopy. He explains the flow of the procedure and describes the risks and benefits of the procedure to the patient and her husband. The patient says she understands all the risks and benefits and agrees to undergo the procedure, but her husband disagrees and insists that he should have the final word because his wife is \"a mentally unstable woman.\" Which of the following is correct about the informed consent for the procedure in this patient?", "answer": "The patient can make the decision about the treatment herself because she does not show signs of decision-making incapability.", "options": {"A": "The patient can make the decision about the treatment herself because she does not show signs of decision-making incapability.", "B": "The decision must be made by both the wife and the husband because of the patient’s mental illness.", "C": "Because of the patient’s mental disease, the consent should be given by her husband.", "D": "Informed consent is not necessary in this case because the benefit of the procedure for the patient is obvious.", "E": "The patient does not have the capacity to make her own decisions because she is taking a psychotropic medication."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old man is referred to the dermatologist for 2 months of increasing appearance of multiple smooth, circular patches of complete hair loss on his scalp. He says that the patches have associated pruritus and a burning sensation, and are not improving with the over-the-counter products recommended by his hair stylist. He denies pulling his hair intentionally. Physical examination reveals no epidermal inflammation or erythema, and no fluorescence is detected under Wood’s lamp. A punch biopsy shows a peribulbar lymphocytic inflammatory infiltrate surrounding anagen follicles, resembling a swarm of bees. Which of the following is the most likely diagnosis in this patient?", "answer": "Alopecia areata", "options": {"A": "Tinea capitis", "B": "Telogen effluvium", "C": "Lichen planopilaris", "D": "Androgenic alopecia", "E": "Alopecia areata"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 71-year-old woman presents to her hematologist-oncologist for follow up after having begun doxorubicin and cyclophosphamide in addition to radiation therapy for the treatment of her stage 3 breast cancer. Her past medical history is significant for preeclampsia, hypertension, polycystic ovarian syndrome, and hypercholesterolemia. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and denies any illicit drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 111/min, and respiratory rate 23/min. On physical examination, the pulses are strong and irregular, she has a grade 3/6 holosystolic murmur heard best at the left upper sternal border, clear bilateral breath sounds, and erythema over her site of radiation. Which of the following statements regarding doxorubicin is true?", "answer": "Doxorubicin has a maximum lifetime dose, due to the risk of cardiac toxicity", "options": {"A": "Doxorubicin frequently causes an acneiform rash", "B": "Doxorubicin will increase her risk for deep vein thrombosis (DVT) and pulmonary embolism (PE)", "C": "Doxorubicin has a maximum lifetime dose, due to the risk of cardiac toxicity", "D": "Doxorubicin has a maximum lifetime dose, due to the risk of pulmonary toxicity", "E": "Doxorubicin frequently causes cystitis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old man comes to the physician because of a 3-week history of left testicular swelling. He has no pain. He underwent a left inguinal hernia repair as a child. He takes no medications. He appears healthy. His vital signs are within normal limits. Examination shows an enlarged, nontender left testicle. When the patient is asked to cough, there is no bulge present in the scrotum. When a light is held behind the scrotum, it does not shine through. There is no inguinal lymphadenopathy. Laboratory studies show:\nHemoglobin 14.5 g/dL\nLeukocyte count 8,800/mm3\nPlatelet count 345,000/mm3\nSerum\nGlucose 88 mg/dL\nCreatinine 0.8 mg/dL\nTotal bilirubin 0.7 mg/dL\nAlkaline phosphatase 35 U/L\nAST 15 U/L\nALT 14 U/L\nLactate dehydrogenase 60 U/L\nβ-Human chorionic gonadotropin 80 mIU/mL (N < 5)\nα-Fetoprotein 6 ng/mL (N < 10)\nWhich of the following is the most likely diagnosis?\"", "answer": "Seminoma", "options": {"A": "Leydig cell tumor", "B": "Spermatocele of testis", "C": "Choriocarcinoma", "D": "Yolk sac tumor", "E": "Seminoma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 33-year-old woman presents to the emergency department with pain in her right wrist. She says she was walking on the sidewalk a few hours ago when she suddenly slipped and landed forcefully on her outstretched right hand with her palm facing down. The patient is afebrile, and vital signs are within normal limits. Physical examination of her right wrist shows mild edema and tenderness on the lateral side of the right hand with a decreased range of motion. Sensation is intact. The patient is able to make a fist and OK sign with her right hand. A plain radiograph of her right wrist is shown in the image. Which of the following bones is most likely fractured in this patient?", "answer": "Bone labeled 'D'", "options": {"A": "Bone labeled 'A'", "B": "Bone labeled 'B'", "C": "Bone labeled 'C'", "D": "Bone labeled 'D'", "E": "Bone labeled 'E'"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old primigravida presents to her physician for regular prenatal care at 31 weeks gestation . She has no complaints and the antepartum  course has been uncomplicated. Her pre-gestational history is significant for obesity (BMI = 30.5 kg/m2). She has gained a total of 10 kg (22.4 lb) during pregnancy,; and  2 kg (4.48 lb) since her last visit 4 weeks ago. Her vital signs are as follows: blood pressure, 145/90 mm Hg; heart rate, 87/min; respiratory rate, 14/min; and temperature, 36.7℃ (98℉). The fetal heart rate is 153/min. The physical examination shows no edema and is only significant for a 2/6 systolic murmur best heard at the apex of the heart. A 24-hour urine is negative for protein. Which of the following options describe the best management strategy in this case?", "answer": "Observation in the outpatient settings", "options": {"A": "Admission to hospital for observation", "B": "Treatment in outpatient settings with labetalol", "C": "Observation in the outpatient settings", "D": "Treatment in the inpatient settings with methyldopa", "E": "Treatment in the outpatient settings with nifedipine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old boy is brought to the physician by his father because of fever, congestion, and malaise for the past 2 days. He reports a sensation of pressure over his nose and cheeks. Over the past year, he has had an intermittent cough productive of green sputum and lately has noticed some streaks of blood in the sputum. He has had over 10 episodes of sinusitis, all of which were successfully treated with antibiotics. There is no family history of serious illness. The patient's vaccinations are up-to-date. His temperature is 38°C (100.4°F), pulse is 90/min, and blood pressure is 120/80 mm Hg. Physical examination shows tenderness to palpation over both cheeks. Crackles and rhonchi are heard on auscultation of the chest. Cardiac examination shows an absence of heart sounds along the left lower chest. Which of the following additional findings is most likely in this patient?", "answer": "Immotile sperm", "options": {"A": "Defective interleukin-2 receptor gamma chain", "B": "Absence of B lymphocytes", "C": "Increased forced expiratory volume", "D": "Increased sweat chloride levels", "E": "Immotile sperm"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old woman presents with episodes of intermittent fever, arthralgias, constant fatigue, weight loss, and plaque-like rash on sun-exposed areas, which have been gradually increasing over the last 6 months. On presentation, her vital signs include: blood pressure is 110/80 mm Hg, heart rate is 87/min, respiratory rate is 14/min, and temperature is 37.5°C (99.5°F). Physical examination reveals an erythematous scaling rash on the patient’s face distributed in a ‘butterfly-like’ fashion, erythematous keratinized patches on the sun-exposed areas, and mild lower leg edema. During the workup, the patient is found to be positive for anti-Sm (anti-Smith) antibodies. Which process is altered in this patient?", "answer": "Ineffective clearance of cellular debris", "options": {"A": "Base-excision repair", "B": "DNA transcription", "C": "Protein folding", "D": "Mismatch repair", "E": "Ineffective clearance of cellular debris"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A medical student is reviewing dose-response curves of various experimental drugs. She is specifically interested in the different factors that cause the curve to shift in different directions. From her study, she plots the following graph (see image). She marks the blue curve for drug A, which acts optimally on a receptor. After drawing the second (green) curve, she discovers that this drug B has a lower ability to produce a reaction than the first one. She also discovers that more of the second drug B is required to produce the same response as the first one. Which of the following terms best describes the activity of drug B in comparison to drug A?", "answer": "Lower potency", "options": {"A": "Lower potency", "B": "Higher efficacy", "C": "Higher potency", "D": "Increased affinity", "E": "Decreased efficacy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 40-year-old woman comes to the physician because of a 3-month history of a lump on her neck. The lump is mildly painful. She appears healthy. Examination shows a swelling on the left side of her neck that moves on swallowing. Cardiopulmonary examination shows no abnormalities. Her TSH is 3.6 μU/mL. Ultrasound shows a 0.4-cm (0.15-in) hypoechoic mass in the left thyroid lobe. Fine-needle aspiration of the mass shows neoplastic follicular cells. Molecular analysis of the aspirate shows a mutation in the RAS gene. Which of the following is the most appropriate next step in management?", "answer": "Thyroid lobectomy", "options": {"A": "Watchful waiting", "B": "Thyroid lobectomy", "C": "External beam radiation", "D": "Radioiodine therapy", "E": "Total thyroidectomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 46-year-old woman presents to her primary care provider for itching. She reports that she has always had dry skin but that the itching has gotten significantly worse over the last few years. The patient also endorses fatigue and dull abdominal pain. Her past medical history includes Hashimoto’s thyroiditis, mitral valve prolapse, and osteoarthritis. She takes levothyroxine and ibuprofen for pain in her knees. The patient drinks 2-3 beers per week. She has a 10 pack-year smoking history but quit 15 years ago. She denies any family history of cancer. On physical exam, her sclera are anicteric. Her abdomen is soft and tender to palpation in the right upper quadrant. Her bowel sounds are normal and hepatomegaly is present. A right upper quadrant ultrasound shows no evidence of extrahepatic biliary dilation. Laboratory studies are performed which reveal the following:\n\nAspartate aminotransferase (AST): 76 U/L\nAlanine aminotransferase (ALT): 57 U/L\nAlkaline phosphatase: 574 U/L\nTotal bilirubin: 1.6 mg/dL\n\nThis patient is most likely to have which of the following additional findings?", "answer": "Hyperlipidemia", "options": {"A": "Hyperlipidemia", "B": "Skin hyperpigmentation", "C": "Anti-smooth muscle antibodies", "D": "Anti-neutrophil cytoplasmic antibodies", "E": "Personality changes"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 67-year-old man with type 2 diabetes mellitus and benign prostatic hyperplasia comes to the physician because of a 2-day history of sneezing and clear nasal discharge. He has had similar symptoms occasionally in the past. His current medications include metformin and tamsulosin. Examination of the nasal cavity shows red, swollen turbinates. Which of the following is the most appropriate pharmacotherapy for this patient's condition?", "answer": "Desloratadine", "options": {"A": "Desloratadine", "B": "Theophylline", "C": "Diphenhydramine", "D": "Nizatidine", "E": "Amoxicillin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old man presents with recurrent abdominal pain, diarrhea with fatty porridge-like stools and occasional blood up to 8 times per day, joint pain, and weight loss. Ileocolonoscopy shows regions of erythema, swelling, and cobblestone-like appearance of the ascending colon and terminal ileum. Targeted biopsies are taken for evaluation. One of the slides, which underwent histological assessment, is shown in the image. Which of the following best describes the histologic finding marked with the blue circle?", "answer": "Cryptitis", "options": {"A": "Crypt ulcer", "B": "Cryptitis", "C": "Granuloma", "D": "Epithelial cell dysplasia", "E": "Goblet cell aplasia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old man comes to the emergency department because of progressively worsening shortness of breath and fever for 2 days. He also has a nonproductive cough. He does not have chest pain or headache. He has chronic myeloid leukemia and had a bone marrow transplant 3 months ago. His current medications include busulfan, mycophenolate mofetil, tacrolimus, and methylprednisolone. His temperature is 38.1°C (100.6°F), pulse is 103/min, respirations are 26/min, and blood pressure is 130/70 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 93%. Pulmonary examination shows diffuse crackles. The spleen tip is palpated 4 cm below the left costal margin. Laboratory studies show:\nHemoglobin 10.3 g/dL\nLeukocyte count 4,400/mm3\nPlatelet count 160,000/mm3\nSerum\nGlucose 78 mg/dL\nCreatinine 2.1 mg/dL\nD-dimer 96 ng/mL (N < 250)\npp65 antigen positive\nGalactomannan antigen negative\nUrinalysis is normal. An x-ray of the chest shows diffuse bilateral interstitial infiltrates. An ECG shows sinus tachycardia. Which of the following is the most appropriate pharmacotherapy?\"", "answer": "Ganciclovir", "options": {"A": "Levofloxacin", "B": "Valganciclovir", "C": "Acyclovir", "D": "Ganciclovir", "E": "Azithromycin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 20-year-old student is referred to his college's student health department because his roommates are concerned about his recent behavior. He rarely leaves his room, has not showered in several days, appears to be praying constantly even though he is not religious, and has not been studying despite previously being an extremely good student. After evaluating this patient, a physician decides to recommend initiation of pharmacological treatment. The patient's family is concerned because they heard that the drug being recommended may be associated with heart problems. Which of the following characteristics is a property of the most likely drug that was prescribed in this case?", "answer": "Associated with development of retinal deposits", "options": {"A": "Associated with development of corneal deposits", "B": "Associated with development of retinal deposits", "C": "Higher affinity for receptors than comparable drugs", "D": "Less sedation and hypotension than comparable drugs", "E": "More extrapyramidal symptoms than comparable drugs"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A researcher is investigating the risk of symptomatic intracerebral hemorrhage associated with tissue plasminogen activator (tPA) treatment in severe ischemic stroke. The outcomes of a large randomized controlled trial of ischemic stroke patients, some of whom were randomized to tPA, is shown:\nSymptomatic intracerebral hemorrhage No symptomatic intracerebral hemorrhage\nReceived tPA 12 188\nDid not receive tPA 25 475\nBased on this data, how many patients with severe ischemic stroke would need to be treated with tPA, on average, to contribute to one case of symptomatic intracerebral hemorrhage?\"", "answer": "100", "options": {"A": "6", "B": "0.01", "C": "13", "D": "1.2", "E": "100"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 31-year-old Israeli male with a history of heavy smoking presents to your office with painful ulcerations on his hands and feet. Upon examination, he is found to have hypersensitivity to intradermally injected tobacco extract. Which of the following processes is most likely responsible for his condition?", "answer": "Segmental vasculitis of small and medium-sized arteries", "options": {"A": "Increased endothelial permeability", "B": "Necrotizing inflammation involving renal arteries", "C": "Segmental vasculitis of small and medium-sized arteries", "D": "Eosinophil-rich granulomatous inflammation", "E": "Concentric thickening of the arteriolar wall"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old boy is brought to the physician because of increasing swelling of his legs and generalized fatigue for 1 month. During this period he has also had a productive cough and shortness of breath. He has been unable to carry out his daily activities. He has a history of recurrent respiratory tract infections and chronic nasal congestion since childhood. He has a 3-month history of foul-smelling and greasy stools. He is at 4th percentile for height and weight. His temperature is 37°C (98.6°F), pulse is 112/min, respirations are 23/min, and blood pressure is 104/64 mm Hg. Examination shows clubbing of his fingers and scoliosis. There is 2+ pitting edema of the lower extremities. Jugular venous distention is present. Inspiratory crackles are heard in the thorax. Cardiac examination shows a loud S2. The abdomen is mildly distended and the liver is palpated 2 cm below the right costal margin. Hepato-jugular reflux is present. Which of the following is the most likely diagnosis?", "answer": "Cystic fibrosis", "options": {"A": "Minimal change disease", "B": "Hypertrophic cardiomyopathy", "C": "Protein malnutrition", "D": "Goodpasture syndrome", "E": "Cystic fibrosis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 49-year-old female with a long history of poorly controlled diabetes mellitus visits her primary care physician with 2+ non-pitting edema in her legs. The patient has a serum creatinine of 2.9 mg/dL and a blood urea nitrogen of 61 mg/dL. A 24-hour urine collection reveals 8.5 grams of protein. A renal biopsy is obtained. Which of the following histologic findings is most likely to be seen upon tissue analysis:", "answer": "Nodular thickening of the glomerular basement membrane", "options": {"A": "Normal glomeruli", "B": "Nodular thickening of the glomerular basement membrane", "C": "Crescentic proliferation in Bowman’s space", "D": "Lymphocytic infiltration of glomerular tufts", "E": "Non-caseating interstitial granuloma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old man with longstanding history of diabetes mellitus and hypertension presents to the emergency department with sudden-onset numbness. On your neurological exam, you note that he has loss of sensation on the left side of his face, arm, and leg. His motor strength exam is normal, as are his cranial nerves. Which of the following is the most likely explanation for his presentation?", "answer": "Thalamic stroke", "options": {"A": "Anterior cerebral artery stroke", "B": "Middle cerebral artery stroke", "C": "Conversion disorder", "D": "Thalamic stroke", "E": "Basilar artery stroke"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old graduate student is brought to the emergency department by her boyfriend because of chest pain that started 90 minutes ago. Her boyfriend says she has been taking medication to help her study for an important exam and has not slept in several days. On examination, she is diaphoretic, agitated, and attempts to remove her IV lines and ECG leads. Her temperature is 37.6°C (99.7°F), pulse is 128/min, and blood pressure is 163/97 mmHg. Her pupils are dilated. The most appropriate next step in management is the administration of which of the following?", "answer": "Lorazepam", "options": {"A": "Dantrolene", "B": "Activated charcoal", "C": "Ketamine", "D": "Lorazepam", "E": "Haloperidol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old man comes to the emergency department because of abdominal pain, nausea, and vomiting for 4 hours. Initially, the pain was dull and located diffusely around his umbilicus, but it has now become sharper and moved towards his lower right side. He has no history of serious illness and takes no medications. His temperature is 38.2°C (100.7°F) and blood pressure is 123/80 mm Hg. Physical examination shows severe right lower quadrant tenderness without rebound or guarding; bowel sounds are decreased. His hemoglobin concentration is 14.2 g/dL, leukocyte count is 12,000/mm3, and platelet count is 280,000/mm3. Abdominal ultrasonography shows a dilated noncompressible appendix with distinct wall layers and echogenic periappendiceal fat. Intravenous fluid resuscitation is begun. Which of the following is the most appropriate next step in management?", "answer": "Perform laparoscopic appendectomy", "options": {"A": "Begin bowel rest and nasogastric aspiration", "B": "Perform percutaneous drainage", "C": "Prescribe oral amoxicillin and clavulanic acid", "D": "Perform interval appendectomy", "E": "Perform laparoscopic appendectomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 57-year-old man is brought to the emergency department 2 hours after the onset of severe nausea and vomiting. He also has cramping abdominal pain and feels fatigued. Two months ago, he injured his lumbar spine in a car accident and lost complete motor and sensory function below the level of injury. He has been bedridden ever since and is cared for at home. He has type 2 diabetes mellitus and renal insufficiency. Examination shows dry mucosal membranes and sensory impairment with flaccid paralysis in both lower limbs that is consistent with prior examinations. Laboratory studies show:\nSerum\nCalcium 12.8 mg/dL\nParathyroid hormone, N-terminal 180 pg/mL\nThyroid-stimulating hormone 2.5 μU/mL\nThyroxine 8 μg/dL\nCalcitriol Decreased\nCreatinine 2.6 mg/dL\nUrine\nCalcium 550 mg/24 h\nIn addition to administration of intravenous 0.9% saline and calcitonin, which of the following is the most appropriate next step in management?\"", "answer": "Bisphosphonates", "options": {"A": "Reduced calcium intake", "B": "Thiazide diuretics", "C": "Hemodialysis", "D": "Bisphosphonates", "E": "Glucocorticoids"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 49-year-old homeless man comes to the emergency department because of fatigue, cough, and worsening shortness of breath for 2 weeks. He was diagnosed with HIV-infection 25 years ago but has never had any symptoms. He has always refused to take antiretroviral medication. Pulmonary examination shows diffuse crackles over bilateral lower lung fields. An x-ray of the chest shows diffuse, symmetrical interstitial infiltrates. His serum level of beta-d-glucan is elevated. Further testing shows a heterozygous mutation that prevents entry of HIV into macrophages. Which of the following proteins is most likely affected by the mutation in this patient?", "answer": "CCR5", "options": {"A": "ICAM-1", "B": "CCR5", "C": "Gp120", "D": "CD4", "E": "P antigen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old man presents to the emergency department with complaints of red, pinkish urine in the morning. He adds that he has been feeling some abdominal pain. The patient is not taking any medication, and his laboratory test results are as follows:\nHb 11.0 g/dL\nRBC 3.7 x 1012/L\nWBC 4,000/mm3\nPLT 100,000/mm3\nReticulocytes 17% of red cells\nCoombs test Negative\nBlood smear Polychromasia\nWhich statement is true about this patient’s condition?", "answer": "Eculizumab can be used to treat this condition", "options": {"A": "Eculizumab can be used to treat this condition", "B": "CD25 deficiency is expected to be seen", "C": "Patient is at great risk for bleeding", "D": "Rituximab therapy is effective", "E": "Urinary hemosiderin testing will be negative"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 15-year-old man presents with his father to the urgent care with 5 days of frequent diarrhea, occasionally with streaks of blood mixed in. Stool cultures are pending, but preliminary stool samples demonstrate fecal leukocytes and erythrocytes. His vital signs are as follows: blood pressure is 126/83 mm Hg, heart rate is 97/min, and respiratory rate is 15/min. He is started on outpatient therapy for presumed Shigella infection. Which of the following is the most appropriate therapy?", "answer": "Oral TMP-SMX", "options": {"A": "IV erythromycin", "B": "Oral metronidazole", "C": "Oral vancomycin", "D": "Oral doxycycline", "E": "Oral TMP-SMX"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "During subject selection for an infant neurological development study, a child is examined by the primary investigator. She is at the 80th percentile for length and weight. She has started crawling. She looks for dropped objects. She says mama and dada non-specifically. She can perform the pincer grasp. Which of the following additional skills or behaviors would be expected in a healthy patient of this developmental age?", "answer": "Pulls up to stand", "options": {"A": "Engages in pretend play", "B": "Pulls up to stand", "C": "Points to 3 body parts", "D": "Says at least 1 word clearly", "E": "Turns pages in a book"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old man comes to the emergency department because of a 3-week history of abdominal distention, yellow coloring of the skin, and dark urine. He also reports malaise and progressive shortness of breath, associated with slight exertion, for several weeks. The patient is a chronic drinker, and he was diagnosed with cirrhosis 2 years ago. He was warned to stop drinking alcohol, but he continues to drink. He hasn’t accepted any more testing and has refused to visit the doctor until now. His vital signs are heart rate 62/min, respiratory rate 26/min, temperature 37.4°C (99.3°F), and blood pressure 117/95 mm Hg. On physical examination, there is dyspnea and polypnea. Skin and sclera are jaundiced. The abdomen has visible collateral circulation and looks distended. There is diffuse abdominal pain upon palpation in the right hemiabdomen, and the liver is palpated 10 cm below the right costal border. The legs show significant edema. CT scan shows cirrhosis with portal hypertension and collateral circulation. During the fifth day of his hospital stay, the patient presents with oliguria and altered mental status. Laboratory studies show:\n  Day 1\nDay 5\nHemoglobin\n12.1 g/dL\n11.2 g/dL\nHematocrit\n33.3%\n31.4%\nLeukocyte count\n7,000/mm3\n6,880/mm3\nPlatelet count\n220,000/mm3\n134,000/mm3\nTotal bilirubin\n20.4 mg/dL\n28.0 mg/dL\nDirect bilirubin\n12.6 mg/dL\n21.7 mg/dL\nCreatinine\n2.2 mg/dL\n2.9 mg/dL\nAlbumin\n3.4 g/dL\n2.6 g/dL\nPT\n5 s\n16.9 s\naPTT\n19 s\n35 s\nUrinalysis\n  Negative for nitrite\nNegative for leukocyte esterase\n0–2 RBCs per high power field\n0–1 WBC per high power field\nNo evidence of casts or proteinuria\nWhat is the most likely cause of this patient’s increased creatinine?", "answer": "Hepatorenal syndrome", "options": {"A": "Acute tubular necrosis", "B": "Chronic kidney disease", "C": "Glomerulonephritis", "D": "Hepatorenal syndrome", "E": "Pyelonephritis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 73-year-old man is brought to the emergency department because of fever and a productive cough for 2 days. He has had increasing fatigue and dyspnea for the past 2 weeks. During this time he has lost 3 kg (6.6 lb). He received chemotherapy for myelodysplastic syndrome (MDS) 1 year ago. He is currently on supportive treatment and regular blood transfusions. He does not smoke or drink alcohol. The vital signs include: temperature 38.5℃ (101.3℉), pulse 93/min, respiratory rate 18/min, and blood pressure 110/65 mm Hg. He has petechiae distally on the lower extremities and several purpura on the trunk and extremities. Several enlarged lymph nodes are detected in the axillary and cervical regions on both sides. On auscultation of the lungs, crackles are heard in the left lower lobe area. Physical examination of the heart and abdomen shows no abnormalities. The laboratory studies show the following:\nHemoglobin 9 g/dL\nMean corpuscular volume 95 μm3\nLeukocyte count 18,000/mm3\nPlatelet count 40,000/mm3\nProthrombin time 11 sec (INR = 1)\nBased on these findings, this patient is most likely to have developed which of the following?", "answer": "Acute myeloid leukemia", "options": {"A": "Acute myeloid leukemia", "B": "Burkitt lymphoma", "C": "Disseminated intravascular coagulation", "D": "Non-cardiogenic pulmonary edema", "E": "Small cell lung cancer"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 1-year-old girl is brought to the physician for a well-child examination. She has no history of serious illness. She receives a vaccine in which a polysaccharide is conjugated to a carrier protein. Which of the following pathogens is the most likely target of this vaccine?", "answer": "Streptococcus pneumoniae", "options": {"A": "Clostridium tetani", "B": "Hepatitis A virus", "C": "Varicella zoster virus", "D": "Streptococcus pneumoniae", "E": "Bordetella pertussis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old G1P1001 is recovering in the postpartum unit three days after a Caesarean section. Her surgery was indicated for breech presentation of the infant. She was at 40 weeks and 2 days gestation at the time of delivery. The patient is now complaining of purulent discharge and continued heavy bleeding. She also notes difficulty and discomfort with urination. The patient’s prenatal course was complicated by one episode of pyelonephritis, which was treated with intravenous ceftriaxone and suppression nitrofurantoin for the remainder of the pregnancy. The patient has a medical history of generalized anxiety disorder and atopic dermatitis. On the third postpartum day, her temperature is 101.2°F (38.4°C), pulse is 112/min, blood pressure is 118/71 mmHg, and respirations are 13/min. Exam reveals that she is uncomfortable and diaphoretic. Her lochia is purulent with several blood clots, and her uterus is slightly boggy and soft. There is mild tenderness with uterine manipulation. Which of the following is the best next step in management for this patient's condition?", "answer": "Clindamycin and gentamicin", "options": {"A": "Urinalysis and urine culture", "B": "Endometrial culture", "C": "Clindamycin", "D": "Clindamycin and gentamicin", "E": "Ceftriaxone"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "One week after admission to the hospital for an extensive left middle cerebral artery stroke, a 91-year-old woman is unable to communicate, walk, or safely swallow food. She has been without nutrition for the duration of her hospitalization. The patient's sister requests placement of a percutaneous endoscopic gastrostomy tube for nutrition. The patient's husband declines the intervention. There is no living will. Which of the following is the most appropriate course of action by the physician?", "answer": "Encourage a family meeting", "options": {"A": "Proceed with PEG placement", "B": "Consult the hospital ethics committee", "C": "Initiate total parenteral nutrition", "D": "Encourage a family meeting", "E": "Transfer to a physician specialized in hospice care"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old man presents to the emergency department because of severe flank pain. He says that the pain came on suddenly while he was at home and is located on his right side. He also says that he has had fever and chills for the last 2 days, but he did not seek medical attention because he assumed that it was just a cold. His past medical history is significant for intermittent kidney stones, hypertension, peptic ulcer disease, and low back pain. He says that he takes vitamin supplements, antihypertensives, a proton pump inhibitor, and occasional over the counter pain medicine though he doesn't recall the names of these drugs. He also drinks socially with his friends but does not exceed 2 drinks per day. Physical exam reveals severe costovertebral angle tenderness as well as gross hematuria. A computed tomography scan is obtained showing ring shadows in the medullae of the right kidney. Which of the following most likely contributed to the development of this patient's condition?", "answer": "Pain medicine", "options": {"A": "Alcohol", "B": "Antihypertensives", "C": "Pain medicine", "D": "Proton pump inhibitor", "E": "Vitamin supplement"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 13-year-old boy is brought to the emergency department by his parents for severe right hip pain that suddenly started about 2 hours ago. The parents are extremely anxious and feel overwhelmed because the boy has been hospitalized several times in the past for similar episodes of pain. The boy was born at 39 weeks of gestation via spontaneous vaginal delivery. He is up to date on all vaccinations and is meeting all developmental milestones. His only medication is hydroxyurea, which he has been receiving for 3 years. His blood pressure is 125/84 mm Hg, the respirations are 23/min, the pulse is 87/min, and the temperature is 36.7°C (98.0°F). On physical examination, the patient is in distress and has severe pain (8/10) elicited by gentle palpation of the right femoral head. Which of the following conditions has the same pathophysiology as the likely diagnosis for the patient described in this case?", "answer": "Legg-Calve-Perthes disease", "options": {"A": "Iliotibial band syndrome", "B": "Osgood-Schlatter disease", "C": "Legg-Calve-Perthes disease", "D": "Posterior dislocation of the hip", "E": "Developmental dysplasia of the hip"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 21-year-old woman is diagnosed with a rare subtype of anti-NMDA encephalitis. During the diagnostic workup, she was found to have an ovarian teratoma. Her physician is curious about the association between anti-NMDA encephalitis and ovarian teratomas. A causal relationship between this subtype of anti-NMDA encephalitis and ovarian teratomas is suspected. The physician aims to identify patients with anti-NMDA encephalitis and subsequently evaluate them for the presence of ovarian teratomas. Which type of study design would be the most appropriate?", "answer": "Case-control study", "options": {"A": "Cross-sectional study", "B": "Case series", "C": "Case-control study", "D": "Randomized controlled trial", "E": "Retrospective cohort study"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 29-year-old man comes to the physician for a routine health maintenance examination. He feels well. He works as a nurse at a local hospital in the city. Three days ago, he had a needlestick injury from a patient whose serology is positive for hepatitis B. He completed the 3-dose regimen of the hepatitis B vaccine 2 years ago. His other immunizations are up-to-date. He appears healthy. Physical examination shows no abnormalities. He is concerned about his risk of being infected with hepatitis B following his needlestick injury. Serum studies show negative results for hepatitis B surface antigen, hepatitis B surface antibody, and hepatitis C antibody. Which of the following is the most appropriate next step in management?", "answer": "Administer hepatitis B immunoglobulin and 3-dose regimen of hepatitis B vaccine", "options": {"A": "Administer hepatitis B immunoglobulin and single dose hepatitis B vaccine", "B": "Administer hepatitis B immunoglobulin", "C": "Revaccinate with two doses of hepatitis B vaccine", "D": "Revaccinate with 3-dose regimen of hepatitis B vaccine", "E": "Administer hepatitis B immunoglobulin and 3-dose regimen of hepatitis B vaccine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A previously healthy 33-year-old woman comes to the emergency department 1 hour after falling from a ladder. She is conscious. She does not smoke, drink alcohol, or use illicit drugs. There is no family history of serious illness. Her pulse is 72/min, respirations are 17/min, and blood pressure is 110/72 mm Hg. Physical examination shows ecchymosis and point tenderness over the right clavicle. An x-ray of the chest shows a nondisplaced fracture of the midshaft of the right clavicle and a 3.5-mm pulmonary nodule in the central portion of the left upper lung field. No previous x-rays of the patient are available. The fracture is treated with pain management and immobilization with a sling. A CT scan of the chest shows that the pulmonary nodule is solid and has well-defined, smooth borders. Which of the following is the most appropriate next step in management of this patient's pulmonary nodule?", "answer": "Reassurance", "options": {"A": "Reassurance", "B": "Follow-up CT scan of the chest in 6–12 months", "C": "Follow-up x-ray of the chest in 6–12 months", "D": "CT-guided transthoracic biopsy", "E": "Bronchoscopy with biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 36-year-old woman comes to the physician because of multiple episodes of headache over the past 3 months. The headaches last the entire day and are unilateral and throbbing. During the headaches, she has severe nausea and is unable to work and perform her daily activities. She has noticed that she becomes unusually hungry prior to the onset of headache. She locks herself in a dark room, takes ibuprofen, and avoids going out until the headache subsides. However, over the past month, the headaches have increased to 2–3 times a week and become more intense. She has hypertension treated with amlodipine. Her temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 128/76 mm Hg. Physical and neurologic examinations show no abnormalities. Which of the following is the most appropriate therapy for long-term prevention of headaches in this patient?", "answer": "Propranolol", "options": {"A": "Fluoxetine", "B": "Ergotamine", "C": "Propranolol", "D": "Sumatriptan", "E": "Naproxen"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old man presents with a painless genital ulcer for the past 2 weeks. He reports that he recently has been having unprotected sex with multiple partners. Past medical history is unremarkable. On physical examination, a single ulcer is present on the dorsal shaft of the penis which is circumscribed, indurated, and partially healed. There is moderate inguinal lymphadenopathy but no buboes. Which of the following tests would confirm the most likely diagnosis in this patient?", "answer": "Fluorescent treponemal antibody absorption (FTA-ABS) test", "options": {"A": "Viral and rickettsial disease research laboratory (VDRL) test", "B": "Swab the chancre and perform a saline wet mount", "C": "Fluorescent treponemal antibody absorption (FTA-ABS) test", "D": "Frei test", "E": "Perform a darkfield microscopic examination of a swab from the chancre"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Background: Aldosterone blockade reduces mortality and morbidity among patients with severe heart failure. Researchers conducted a double-blind, placebo-controlled study evaluating the effect of eplerenone, a selective aldosterone blocker, on morbidity and mortality among patients with acute myocardial infarction complicated by left ventricular dysfunction and heart failure.\nMethods: Patients were randomly assigned to eplerenone (25 mg per day initially, titrated to a maximum of 50 mg per day; 3,319 patients) or placebo (3,313 patients) in addition to optimal medical therapy. The study continued until 1,012 deaths occurred. The primary endpoints were death from any cause, death from cardiovascular causes, hospitalization for heart failure, acute myocardial infarction, stroke, or ventricular arrhythmia.\nResults: During a mean follow-up of 16 months, there were 478 deaths in the eplerenone group (14.4%) and 554 deaths in the placebo group (16.7%, p = 0.008). Of these deaths, 407 in the eplerenone group and 483 in the placebo group were attributed to cardiovascular causes (relative risk, 0.83; 95 percent confidence interval, 0.72 to 0.94; p = 0.005). The rate of the other primary endpoints, death from cardiovascular causes or hospitalization for cardiovascular events, was reduced by eplerenone (relative risk, 0.87; 95 percent confidence interval, 0.79 to 0.95; p = 0.002), as was the secondary endpoint of death from any cause or any hospitalization (relative risk, 0.92; 95 percent confidence interval, 0.86 to 0.98; p = 0.02). There was also a reduction in the rate of sudden death from cardiac causes (relative risk, 0.79; 95 percent confidence interval, 0.64 to 0.97; p = 0.03). The rate of serious hyperkalemia was 5.5 percent in the eplerenone group and 3.9 percent in the placebo group (p = 0.002), whereas the rate of hypokalemia was 8.4 percent in the eplerenone group and 13.1 percent in the placebo group (p < 0.001).\nWhich of the following represents the number of patients needed to treat to save one life, based on the primary endpoint?", "answer": "1/(0.167 - 0.144)", "options": {"A": "1/(0.144 - 0.167)", "B": "1/(0.136 - 0.118)", "C": "1/(0.300 - 0.267)", "D": "1/(0.167 - 0.144)", "E": "1/(0.267 - 0.300)"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 54-year-old woman presents to the emergency ward with a chief complaint of chest pain. The pain is sharp and present in the anterior part of the chest. There is no radiation of the pain; however, the intensity is decreased while sitting and leaning forward. There is no associated shortness of breath. Vital signs are the following: blood pressure is 132/84 mm Hg; pulse rate is 82/min, rhythmic, and regular. Lungs are clear on auscultation and cardiovascular examination demonstrates scratchy and squeaking sounds at the left sternal border and a 'knock' heard on auscultation. Kussmaul sign is positive and ECG shows new widespread ST segment elevation and PR depression in leads II, III and aVF. The most likely cause for these findings in this patient is?", "answer": "Constrictive pericarditis", "options": {"A": "Constrictive pericarditis", "B": "Pleurisy", "C": "Cardiac tamponade", "D": "Restrictive cardiomyopathy", "E": "Right ventricular myocardial infarction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old man with lymphoma presents to his oncologist with severe abdominal pain and flank pain. He says that the pain started 2 days ago and has gotten worse over time. He has also not been able to urinate over the same time period. On presentation, his temperature is 99°F (37.2°C), blood pressure is 110/72 mmHg, pulse is 105/min, and respirations are 12/min. Physical exam reveals bilateral flank tenderness. Labs results are shown below:\n\nBlood urea nitrogen: 34 mg/dL\nCreatinine: 3.7 mg/dl\nUrine osmolality: 228 mOsm/kg\n\nRenal ultrasonography shows dilation of the kidneys bilaterally with a normal-sized bladder. Which of the following would most likely be beneficial in treating this patient's condition?", "answer": "Bilateral stenting of the ureters", "options": {"A": "Administration of a loop diuretic", "B": "Bilateral stenting of the renal arteries", "C": "Bilateral stenting of the ureters", "D": "Catheterization of the bladder", "E": "Volume repletion with saline"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old man presents with recurrent epigastric pain and diarrhea. He has had these symptoms for the last year or so and has been to the clinic several times with similar complaints. His current dosage of omeprazole has been steadily increasing to combat his symptoms. The pain seems to be related to food intake. He describes his diarrhea as watery and unrelated to his meals. Blood pressure is 115/80 mm Hg, pulse is 76/min, and respiratory rate is 19/min. He denies tobacco or alcohol use. He does not take any medications. An upper endoscopy is performed due to his unexplained and recurrent dyspepsia and reveals thickened gastric folds with three ulcers in the first part of the duodenum, all of which are negative for H. pylori. Which of the following is the best next step in this patient’s management?", "answer": "Fasting serum gastrin levels", "options": {"A": "Serum calcium levels", "B": "Fasting serum gastrin levels", "C": "Secretin stimulation test", "D": "CT scan of the abdomen", "E": "Somatostatin receptor scintigraphy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A mother brings her 7-year-old son to the pediatrician because she is worried about his sleep. She reports that the child has repeatedly woken up in the middle of the night screaming and thrashing. Although she tries to reassure the child, he does not respond to her or acknowledge her presence. Soon after she arrives, he stops screaming and appears confused and lethargic before falling back asleep. When asked about these events, the child reports that he cannot recall ever waking up or having any bad dreams. These events typically occur within four hours of the child going to sleep. The child’s past medical history is notable for asthma and type I diabetes mellitus. He uses albuterol and long-acting insulin. There have been no recent changes in this patient’s medication regimen. His family history is notable for obesity and obstructive sleep apnea in his father. Physical examination reveals a healthy male at the 40th and 45th percentiles for height and weight, respectively. Which of the following EEG waveforms is most strongly associated with this patient’s condition?", "answer": "Delta waves", "options": {"A": "Alpha waves", "B": "Beta waves", "C": "Theta waves", "D": "Delta waves", "E": "Sleep spindles"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man presents to a physician for evaluation of 3 months of increased vertigo. He says that occasionally he will experience several seconds of intense vertigo that makes him lose his balance. He came in for evaluation because this symptom is affecting his ability to drive to work. He has also been occasionally experiencing tinnitus. Physical exam reveals rotatory nystagmus that is delayed in onset and stops with visual fixation. The nerve that is most likely causing these symptoms exits the skull at which of the following locations?", "answer": "Internal auditory meatus", "options": {"A": "Cribriform plate", "B": "Foramen ovale", "C": "Foramen rotundum", "D": "Internal auditory meatus", "E": "Jugular foramen"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old woman comes to the clinic complaining of joint pain and stiffness for the past year. The pain is mainly concentrated in her hands and is usually worse towards the late afternoon. It is described with a burning quality that surrounds the joint with some numbness and tingling. The stiffness is especially worse in the morning and lasts approximately for 15-20 minutes. Her past medical history is significant for recurrent gastric ulcers. She reports that her mother struggled with lupus and is concerned that she might have the same thing. She denies fever, rashes, ulcers, genitourinary symptoms, weight loss, or bowel changes. Physical examination is significant for mild tenderness at the distal interphalangeal joints bilaterally. What is the best initial medication to prescribe to this patient?", "answer": "Acetaminophen", "options": {"A": "Acetaminophen", "B": "Aspirin", "C": "Hydroxychloroquine", "D": "Infliximab", "E": "Methotrexate"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-day-old male newborn is brought to the physician because he became somnolent and felt cold after breastfeeding. Pregnancy and delivery were uncomplicated. He was born at 40 weeks' gestation and weighed 3538 g (7 lb 13 oz); he currently weighs 3311 g (7 lb 5 oz). Examination shows generalized hypotonia. Serum studies show an ammonia concentration of 150 μmol/L (N < 50 μmol/L). Which of the following is the most likely cause of the patient's neurological symptoms?", "answer": "Decreased γ-aminobutyric acid concentration", "options": {"A": "Increased α-ketoglutarate concentration", "B": "Increased succinyl-CoA concentration", "C": "Increased glutamate concentration", "D": "Decreased acylcarnitine concentration", "E": "Decreased γ-aminobutyric acid concentration"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old man comes to the physician because of several months of recurrent abdominal pain and diarrhea. Six months ago, he traveled to Lake Superior for a fishing trip with his friends, during which they often ate their day's catch for dinner. Physical examination shows pallor. Laboratory studies show macrocytic anemia with eosinophilia. A peripheral blood smear shows hypochromic red blood cells with megaloblasts and hypersegmented neutrophils. A cestode infection is suspected and a drug is prescribed that kills cestodes by inducing uncontrollable muscle spasm in the parasite. The drug prescribed for this patient most likely acts by which of the following mechanisms of action?", "answer": "Increased calcium influx into the sarcoplasm", "options": {"A": "Blockade of myosin binding sites", "B": "Increased calcium influx into the sarcoplasm", "C": "Increased sodium efflux from the sarcoplasm", "D": "Increased potassium efflux from the sarcoplasm", "E": "Phosphorylation of adenosine diphosphate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old male is brought to the emergency department by his friends after a camping trip. He and his friends were in the woods camping when the patient started experiencing severe right upper quadrant abdominal pain after foraging and ingesting some wild mushrooms about 3 hours earlier. The patient is lethargic on exam and appears jaundiced. He has scleral icterus and is severely tender to palpation in the right upper quadrant. He has scattered petechiae on his extremities. Liver function tests are:\n\nSerum:\nNa+: 134 mEq/L\nCl-: 100 mEq/L\nK+: 4.2 mEq/L\nHCO3-: 24 mEq/L\nUrea nitrogen: 50 mg/dL\nGlucose: 100 mg/dL\nCreatinine: 1.4 mg/dL\nAlkaline phosphatase: 400 U/L\nAspartate aminotransferase (AST, GOT): 3278 U/L\nAlanine aminotransferase (ALT, GPT): 3045 U/L\ngamma-Glutamyltransferase (GGT): 100 U/L\n\nThe most likely cause of this patient’s clinical presentation acts by inhibiting which of the following molecules?", "answer": "RNA polymerase II", "options": {"A": "RNA polymerase I", "B": "RNA polymerase II", "C": "RNA polymerase III", "D": "Prokaryote RNA polymerase", "E": "Topoisomerase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An otherwise healthy 39-year-old woman presents to her primary care provider because of right-leg swelling, which started 4 months ago following travel to Kenya. The swelling has been slowly progressive and interferes with daily tasks. She denies smoking or alcohol use. Family history is irrelevant. Vital signs include: temperature 38.1°C (100.5°F), blood pressure 115/72 mm Hg, and pulse 99/min. Physical examination reveals non-pitting edema of the entire right leg. The overlying skin is rough, thick and indurated. The left leg is normal in size and shape. Which of the following is the most likely cause of this patient condition?", "answer": "Obstruction of lymphatic channels", "options": {"A": "Persistent elevation of venous pressures", "B": "Lymphatic hypoplasia", "C": "Obstruction of lymphatic channels", "D": "Hypoalbuminemia", "E": "Venous thromboembolism"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 13-day-old male is brought in by his mother for eye redness and ocular discharge. Additionally, the mother reports that the patient has developed a cough and nasal discharge. Pregnancy and delivery were uncomplicated, but during the third trimester, the mother had limited prenatal care. Immediately after delivery, the baby was given silver nitrate drops and vitamin K. Upon visual examination of the eyes, mucoid ocular discharge and eyelid swelling are noted. A fluorescein test is negative. On lung exam, scattered crackles are appreciated. A chest radiograph is performed that shows hyperinflation with bilateral infiltrates. Which of the following is the best pharmacotherapy for this patient's underlying condition?", "answer": "Oral erythromycin", "options": {"A": "Artificial tears", "B": "Intravenous ceftriaxone", "C": "Topical erythromycin", "D": "Oral erythromycin", "E": "Intravenous acyclovir"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 12-year-old girl presents to her primary care physician with left knee pain for the past 6 weeks. She recently joined the field hockey team at her school. The pain is the most severe when she is running up and down the stairs at the school stadium. The pain decreases when she goes home and rests after practice. She additionally admits to tripping and landing on her left knee 5 days ago. Physical exam shows a knee with a healing abrasion over the left patella. The tibial tuberosity is tender to palpation. A radiograph of the knee is presented in figure A. Which of the following is the most likely diagnosis?", "answer": "Osgood-Schlatter disease", "options": {"A": "Osgood-Schlatter disease", "B": "Patellar tendonitis", "C": "Patellofemoral pain syndrome", "D": "Pes anserine bursitis", "E": "Tibial plateau fracture"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 80-year-old woman died due to the respiratory complications of lung cancer. She had been a heavy smoker, and battled COPD and adenocarcinoma of the lungs for the last 20 years. The autopsy also revealed a pathological finding in the mitral valve. Which of the following was most likely seen?", "answer": "Non-destructive vegetations", "options": {"A": "Destructive vegetations", "B": "Non-destructive vegetations", "C": "Ruptured papillary muscle", "D": "Stenosis of leaflets", "E": "Discoloration of leaflets"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old gravida 2 para 1 woman at 16 weeks gestation presents for prenatal care. Her prenatal course has been uncomplicated. She takes no medications besides her prenatal vitamin which she takes every day, and she has been compliant with routine prenatal care. She has a 7-year-old daughter who is healthy. The results of her recent quadruple screen are listed below:\n\nAFP: Low\nhCG: Low\nEstriol: Low\nInhibin-A: Normal\n\nWhich of the following is the most appropriate next step to confirm the diagnosis?", "answer": "Amniocentesis", "options": {"A": "Amniocentesis", "B": "Chorionic villus sampling", "C": "Folic acid supplementation", "D": "Return to clinic in 4 weeks", "E": "Ultrasound for nuchal translucency"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old primigravida woman comes for her primary care physician for the second prenatal visit. She is 10 weeks pregnant. She has no current complaint except for occasional nausea. She does not have any chronic health problems. She denies smoking or alcohol intake. Her family history is positive for paternal colon cancer at the age of 55. Vital signs include a temperature of 37.1°C (98.8°F), blood pressure of 120/60 mm Hg, and pulse of 90/min. Physical examination discloses no abnormalities. According to the United States Preventive Services Task Force (USPSTF), which of the following screening tests is recommended for this patient?", "answer": "Colonoscopy for colorectal cancer at the age of 40", "options": {"A": "Colonoscopy for colorectal cancer at the age of 50", "B": "Glucose tolerance test for gestational diabetes mellitus", "C": "Urine culture for asymptomatic bacteriuria", "D": "Colonoscopy for colorectal cancer at the age of 40", "E": "HbA1C for type 2 diabetes mellitus"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 20-year-old college student presents to her college's mental health services department because her dean has been concerned about her academic performance. She was previously a straight A student; however, she has been barely passing her exams since the death of her younger brother in an accident 5 months ago. She reveals that she feels guilty for not spending more time with him in the years leading up to his death. Furthermore, she has been experiencing abdominal pain when she thinks about him. Additional questioning reveals that she is convinced that her brother simply went missing and will return again despite her being at his funeral. Finally, she says that she saw a vision of her brother in his childhood bedroom when she went home for winter break. Which of the following symptoms indicates that this patient's grief is pathologic?", "answer": "Delusions about her brother", "options": {"A": "Delusions about her brother", "B": "Duration of the grief", "C": "Feelings of guilt", "D": "Hallucinations about her brother", "E": "Somatic symptoms"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old gentleman presents to his primary care physician for difficulties with his gait and recent fatigue. The patient works in a health food store, follows a strict vegan diet, and takes an array of supplements. He noticed that his symptoms have progressed over the past year and decided to see a physician when he found himself feeling abnormally weak on a daily basis in conjunction with his trouble walking. The patient has a past medical history of Crohn's disease, diagnosed in his early 20's, as well as Celiac disease. He states that he has infrequent exacerbations of his Crohn's disease. Recently, the patient has been having worsening bouts of diarrhea that the patient claims is non-bloody. The patient is not currently taking any medications and is currently taking traditional Chinese medicine supplements. Physical exam is notable for 3/5 strength in the upper and lower extremities, absent upper and lower extremity reflexes, and a staggering, unbalanced gait. Laboratory values reveal the following:\n\nSerum:\nNa+: 135 mEq/L\nCl-: 100 mEq/L\nK+: 5.6 mEq/L\nHCO3-: 22 mEq/L\nBUN: 27 mg/dL\nGlucose: 79 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 8.4 mg/dL\nMg2+: 1.5 mEq/L\n\nLeukocyte count and differential:\nLeukocyte count: 4,522/mm^3\nHemoglobin: 9.2 g/dL\nHematocrit: 29%\nPlatelet count: 169,000/mm^3\nReticulocyte count: 2.5%\nLactate dehydrogenase: 340 U/L\nMean corpuscular volume: 97 fL\n\nWhich of the following is most likely deficient in this patient?", "answer": "Vitamin E", "options": {"A": "Vitamin B9", "B": "Vitamin B12", "C": "Vitamin D", "D": "Vitamin E", "E": "Iron"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man comes to the physician because of fatigue and decreased urine output for 2 weeks. He has not been to the physician for many years and takes no medications. Serum studies show a urea nitrogen concentration of 42 mg/dL and a creatinine concentration of 2.3 mg/dL. Urinalysis shows heavy proteinuria. A photomicrograph of a section of a kidney biopsy specimen is shown. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Diabetes mellitus", "options": {"A": "Diabetes mellitus", "B": "Amyloidosis", "C": "Fibromuscular dysplasia", "D": "Severe hypertension", "E": "Dyslipidemia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old male comes to the physician because of a 2-day history of blisters and brownish discoloration of urine. His symptoms appeared after he returned from a 4-day trip with his friends in Florida. He has had similar episodes of blistering twice in the past three years. Each episode resolved spontaneously after a few weeks. Examination shows vesicles and bullae on the face and the dorsal surfaces of his hands and forearms. His condition is most likely caused by a defect in which of the following enzymes?", "answer": "Uroporphyrinogen III decarboxylase", "options": {"A": "Aminolevulinic acid dehydratase", "B": "Uroporphyrinogen III synthase", "C": "Porphobilinogen deaminase", "D": "Uroporphyrinogen III decarboxylase", "E": "Aminolevulinic acid synthase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 21-year-old man presents with eye redness, itching, and watering; nasal congestion, and rhinorrhea. He reports that these symptoms have been occurring every year in the late spring since he was 18 years old. The patient’s medical history is significant for endoscopic resection of a right maxillary sinus polyp at the age of 16. His father and younger sister have bronchial asthma. He takes oxymetazoline as needed to decrease nasal congestion. The patient’s blood pressure is 120/80 mm Hg, heart rate is 71/min, respiratory rate is 18/min, and temperature is 36.7°C (98.0°F). On physical examination, there is conjunctival injection and clear nasal discharge bilaterally. His lymph nodes are not enlarged and his sinuses do not cause pain upon palpation. Heart and lung sounds are normal. Which of the following is most likely to be a part of his condition’s pathogenesis?", "answer": "Excessive release of histamine by the mast cells", "options": {"A": "Production of specific IgM antibodies by B lymphocytes", "B": "Secretion of granzymes and perforin by cytotoxic T lymphocytes", "C": "Excessive release of histamine by the mast cells", "D": "IL-2 secretion by Th1 lymphocytes", "E": "Release of reactive oxygen species by neutrophils"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A medicine resident on her nephrology rotation notices that she has received more alerts of high serum potassium levels on her patients through the hospital electronic medical record despite her census not having changed. On inspection of the laboratory result reports, critical alert markers are seen for potassium values greater than 5.5 mEq/L 3 days ago, whereas the same alerts are seen for values > 5.0 mEq/L since yesterday. One of her patient's nurses asks if the patient should get an electrocardiogram. How has the potassium value reporting been affected?", "answer": "Sensitivity increased and specificity decreased", "options": {"A": "Sensitivity decreased and specificity decreased", "B": "Sensitivity decreased and specificity increased", "C": "Sensitivity increased and specificity decreased", "D": "Sensitivity increased and specificity increased", "E": "Sensitivity increased and specificity unchanged"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 53-year-old woman comes to the emergency department because of blurry vision, headache, and multiple episodes of nosebleeds over the last few weeks. During this time, she has also been itching a lot, especially after getting ready for work in the mornings. She has had an 8-kg (17.6-lb) weight loss and increasing fatigue during the past 6 months. Her temperature is 37.8°C (100.0°F), pulse is 80/min, respirations are 15/min, and blood pressure is 158/90 mm Hg. Physical examination shows no lesions or evidence of trauma in the nasal cavity. Her face, palms, nail beds, oral mucosa, and conjunctiva appear red. Abdominal examination shows splenomegaly. Her hemoglobin concentration is 19 g/dL, hematocrit is 58%, platelets are 450,000/μL, and erythropoietin level is below normal. A peripheral blood smear shows RBC precursor cells. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Mutated JAK2 gene", "options": {"A": "Stress erythrocytosis", "B": "Mutated JAK2 gene", "C": "Increased intracranial pressure", "D": "Megakaryocyte proliferation", "E": "Renal cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman comes to the physician because of a 2-month history of fatigue, muscle weakness, paresthesias, headache, and palpitations. Her pulse is 75/min and blood pressure is 152/94 mm Hg. Physical examination shows no abnormalities. Serum studies show:\nSodium 144 mEq/L\nPotassium 2.9 mEq/L\nBicarbonate 31 mEq/L\nCreatinine 0.7 mg/dL\nFurther evaluation shows low serum renin activity. Which of the following is the most likely diagnosis?\"", "answer": "Aldosteronoma", "options": {"A": "Renal artery stenosis", "B": "Cushing syndrome", "C": "Aldosteronoma", "D": "Laxative abuse", "E": "Pheochromocytoma\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old man presents to the emergency department with a 3-day history of fever and severe back pain. The fever is high-grade, continuous, without chills and rigors. The back pain is severe, localized to the thoracic region, and aggravated by deep breathing. The patient tried taking ibuprofen with little improvement. Past medical history is significant for essential hypertension, dyslipidemia, hyperuricemia, and bronchial asthma. Current medicines include allopurinol, amlodipine, atorvastatin, clopidogrel, montelukast, and a corticosteroid inhaler. The patient reports a 25-pack-year smoking history and drinks alcohol only socially. His vital signs include: blood pressure 152/94 mm Hg, pulse 101/min, temperature 39.5°C (103.1°F). BMI 36.8 kg/m2. On physical examination, the patient is alert and oriented. Multiple injection marks are visible around the left-sided cubital fossa and hand veins. The neck is supple on head flexion. Point tenderness is present in the thoracic region at the midline. Motor and sensory examinations are unremarkable with normal deep tendon reflexes. Laboratory findings are significant for the following:\nHemoglobin 14.5 mg/dL\nWhite blood cell 24,500/mm3\nPlatelets 480,000/mm3\nBUN 28 mg/dL\nCreatinine 1.1 mg/dL\nESR 45 mm/hr\nC-reactive protein 84 mg/dL\nSodium 144 mEq/L\nPotassium 4.1 mEq/L\nCalcium 9.7 mEq/L\nA contrast MRI of the spine reveals a peripherally enhancing dorsal epidural process compressing the thecal sac and causing a mild leftwards displacement. Which of the following is the most likely risk factor for this patient’s condition?", "answer": "Intravenous drug use", "options": {"A": "Alcohol use", "B": "Increased BMI", "C": "Inhaled steroid use", "D": "Intravenous drug use", "E": "Smoking"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 33-year-old man presents to his primary care physician for left-sided knee pain. The patient has a history of osteoarthritis but states that he has been unable to control his pain with escalating doses of ibuprofen and naproxen. His past medical history includes diabetes mellitus and hypertension. His temperature is 102.0°F (38.9°C), blood pressure is 167/108 mmHg, pulse is 100/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam reveals a warm and tender joint that is very tender to the touch and with passive range of motion. The patient declines a gait examination secondary to pain. Which of the following is the best next step in management?", "answer": "Arthrocentesis", "options": {"A": "Antibiotics", "B": "Arthrocentesis", "C": "Colchicine", "D": "IV steroids", "E": "Rest, elevation, and ice"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man presents with fever and yellow discoloration of the skin for the past 4 days. He denies any recent weight loss or changes in urine or stool color. His past medical history is unremarkable. He admits to drinking about 130 g/day of alcohol and says he has been doing so for the past 25 years. His wife who is accompanying him during this visit adds that once her husband drank 15 cans of beer at a funeral. The patient also reports a 10-pack-year smoking history. His vital signs include: pulse 98/min, respiratory rate 13/min, temperature 38.2°C (100.8°F) and blood pressure 120/90 mm Hg. On physical examination, the patient appears jaundiced and is ill-appearing. Sclera is icteric. Abdominal examination reveals tenderness to palpation in the right upper quadrant with no rebound or guarding. Percussion reveals significant hepatomegaly extending 3 cm below the right costal margin. Laboratory studies are significant for the following:\nSodium 135 mEq/L\nPotassium 3.5 mEq/L\nALT 240 mEq/L\nAST 500 mEq/L\nA liver biopsy is obtained but the results are pending. Which of the following would most likely be seen in this patient’s biopsy?", "answer": "Mallory-Denk bodies", "options": {"A": "Gaucher cells", "B": "'Florid' bile duct lesion", "C": "Steatosis alone", "D": "Mallory-Denk bodies", "E": "Hürthle cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Six days after undergoing a thoracic endovascular aortic repair following a high-speed motorcycle accident, a 29-year-old woman develops a fever, cough, and shortness of breath. Serum studies show a sodium concentration of 129 mEq/L. An x-ray of the chest shows a left-sided pleural effusion. Thoracentesis is performed and shows milky white fluid in the pleural space that remains uniform after centrifugation. A culture of the pleural fluid shows no organisms. Further analysis of the fluid would most likely show which of the following?", "answer": "High triglycerides", "options": {"A": "High triglycerides", "B": "Antinuclear antibodies", "C": "High adenosine deaminase", "D": "Cholesterol crystals", "E": "High LDH"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 12-year-old boy presents to the emergency department with a swollen and painful knee. He says that he was exploring with his friends when he tripped and hit his knee against the ground. He didn't feel like he hit it very hard but it started swelling and becoming very painful. His mom reports that he has always been prone to bleeding from very minor trauma and that others in the family have had similar problems. Based on clinical suspicion a coagulation panel was obtained showing a prothrombin time (PT) of 10 seconds (normal range 9-11 seconds), a partial thromboplastin time (PTT) of 45 seconds (normal 20-35 seconds), and a normal ristocetin cofactor assay (equivalent to bleeding time). Mixing tests with factor IX and XI do not show complementation, but mixing with factor VIII reverses the coagulation abnormality. Which of the following is the most likely diagnosis for this patient?", "answer": "Hemophilia A", "options": {"A": "Bernard-Soulier disease", "B": "Glanzmann thrombasthenia", "C": "Hemophilia A", "D": "Hemophilia B", "E": "von Willebrand disease"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 21-year-old man is brought to the emergency department 4 hours after the sudden onset of shortness of breath and pleuritic chest pain. He has smoked 1 pack of cigarettes daily for the past 3 years. He is 188 cm (6.2 ft) tall and weighs 70 kg (154 lb); BMI is 19.8 kg/m2. Physical examination shows decreased tactile fremitus and diminished breath sounds over the left lung. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Rupture of a subpleural bleb", "options": {"A": "Embolic occlusion of the pulmonary artery", "B": "Rupture of a subpleural bleb", "C": "Infection with gram-positive diplococci", "D": "Hyperresponsiveness of the bronchial system", "E": "Inflammation of the costal cartilage"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old girl brought to the emergency department by her mother with seizures. The blood glucose is 94 mg/dl and the serum calcium is 5.3 mg/dl; however, the PTH levels are low. The medical history includes a delay in achieving developmental milestones. Her mother also says she needs frequent hospital visits due to recurrent bouts with the flu. The cardiovascular examination is within normal limits. What is the most likely cause underlying this presentation?", "answer": "Deletion of the chromosome 22q11", "options": {"A": "B cell maturation failure", "B": "B cell development failure", "C": "Lysosomal trafficking regulator gene defect", "D": "Deletion of the chromosome 22q11", "E": "Mutation in the WAS gene"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old woman comes to the physician because of a 9-month history of progressive fatigue. Examination shows pallor. Her hemoglobin concentration is 8.9 g/dL, mean corpuscular volume is 75 μm3, and serum ferritin is 9 ng/mL. Test of the stool for occult blood is positive. Colonoscopy shows an irregular, bleeding 3-cm exophytic ulcer in the right colon. Which of the following lesions is the greatest risk factor for this patient's condition?", "answer": "Villous adenomatous polyp", "options": {"A": "Submucosal lipomatous polyp", "B": "Serrated hyperplastic polyp", "C": "Villous adenomatous polyp", "D": "Tubular adenomatous polyp", "E": "Pedunculated inflammatory polyp"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old woman comes to the physician for the evaluation of dry cough and some chest tightness for the past several weeks. The cough is worse at night and while playing volleyball. She frequently has a runny nose and nasal congestion. Her mother has systemic lupus erythematosus. The patient has smoked one pack of cigarettes daily for the last 5 years. She does not drink alcohol. Her only medication is cetirizine. Her vital signs are within normal limits. Pulse oximetry on room air shows an oxygen saturation of 98%. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Spirometry", "options": {"A": "Spirometry", "B": "Blood gas analysis", "C": "Methacholine challenge test", "D": "CT scan of the chest", "E": "Laboratory studies"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 8-year-old male presents to his pediatrician with dry, cracking skin on his hands. His mother states that this problem has been getting progressively worse over the past couple of months. During this time period, she has noticed that he also has become increasingly concerned with dirtiness. He tearfully admits to washing his hands many times a day because \"everything has germs.\" When asked what happens if he doesn't wash them, he responds that he just feels very worried until he does. With which other condition is this disorder associated?", "answer": "Tourette's syndrome", "options": {"A": "Tourette's syndrome", "B": "Obessive-compulsive personality disorder", "C": "Delusional disorder", "D": "Rett's disorder", "E": "Autism spectrum disorders"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old man of Mediterranean descent comes to the clinic with complaints of fatigue for the past month. He reports that it is increasingly difficult for him to complete his after-dinner walks as he would get breathless and tired around 10 minutes. He endorses dizziness and an upper respiratory infection last week for which he “took a lot of aspirin.” Past medical history is significant for malaria 10 years ago (for which he was adequately treated with anti-malarial medications) and aortic stenosis status post prosthetic valve replacement 5 months ago. When asked if he has had similar episodes before, he claims, “Never! I’ve been as healthy as a horse until my heart surgery.” Physical examination is significant for mild scleral icterus bilaterally and a faint systolic murmur. Which of the following images represents a potential peripheral smear in this patient?", "answer": "A", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 50-year-old man with a remote history of intravenous drug use and a past medical history of AIDS presents to his primary care provider with several weeks of productive cough and a mild fever. He was in his normal state of health and slowly started to develop these symptoms. He is hoping to be prescribed an antibiotic so he can get back to “normal”. Family history is significant for cardiovascular disease and diabetes. He takes antiviral medication and a multivitamin daily. His heart rate is 90/min, respiratory rate is 19/min, blood pressure is 135/85 mm Hg, and temperature is 38.3°C (100.9°F). On physical examination, he looks uncomfortable. A chest examination reveals consolidation in the right lower lung. Chest radiography confirms right lower lobe pneumonia. Of the following options, which is the most likely cause of the patient’s pneumonia?", "answer": "Community-acquired pneumonia", "options": {"A": "Aspiration pneumonia", "B": "Community-acquired pneumonia", "C": "Disseminated cutaneous infection", "D": "Pneumocystis pneumonia", "E": "Pulmonary sequestration"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A two-year-old female presents to the pediatrician with her mother for a routine well-child visit. Her mother is concerned that the patient is a picky eater and refuses to eat vegetables. She drinks milk with meals and has juice sparingly. She goes to sleep easily at night and usually sleeps for 11-12 hours. The patient has trouble falling asleep for naps but does nap for 1-2 hours a few times per week. She is doing well in daycare and enjoys parallel play with the other children. Her mother reports that she can walk down stairs with both feet on each step. She has a vocabulary of 10-25 words that she uses in the form of one-word commands. She is in the 42nd percentile for height and 48th percentile for weight, which is consistent with her growth curves. On physical exam, she appears well nourished. She can copy a line and throw a ball. She can follow the command to “give me the ball and then close the door.”\n\nThis child is meeting her developmental milestones in all but which of the following categories?", "answer": "Expressive language skills", "options": {"A": "Fine motor skills", "B": "Gross motor skills", "C": "Expressive language skills", "D": "Social and receptive language skills", "E": "This child is developmentally normal"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman presents to the office with complaints of frothy urine and swelling in her body that started 6 days ago. She says that she first noticed the swelling in her face that gradually involved other parts of her body. On further questioning, she gives a history of rheumatoid arthritis for 2 years. She is taking Penicillamine and Methotrexate for the past 6 months. Vitals include: blood pressure 122/89 mm Hg, pulse rate 55/min, temperature 36.7°C (98.0°F), and a respiratory rate 14/min. On examination, there is generalized pitting edema along with some subcutaneous nodules on the dorsal aspect of the forearm.\nUrinalysis\npH 6.6\nColor light yellow\nRBC none\nWBC 1–2/HPF\nProtein 4+\nCast fat globules\nGlucose absent\nCrystal none\nKetone absent\nNitrite absent\n24 hours urine protein excretion  4.8 g\n    Basic metabolic panel\nSodium 141 mEq/L\nPotassium 5.1 mEq/L\nChloride 101 mEq/L\nBicarbonate 22 mEq/L\nAlbumin 3.2 mg/dL\nUrea nitrogen 17 mg/dL\nCreatinine 1.3 mg/dL\nUric Acid 6.8 mg/ dL\nCalcium 8.9 mg/ dL\nGlucose 111 mg/dL\nA renal biopsy is ordered which shows diffuse capillary and glomerular basement membrane thickening. Which of the following is the most likely cause for her impaired renal function?", "answer": "Membranous nephropathy", "options": {"A": "Lipoid nephrosis", "B": "Minimal change disease", "C": "Membranous nephropathy", "D": "Renal amyloidosis", "E": "Diabetic glomerulonephropathy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old man with a history of alcohol binge drinking and polysubstance use is found down in his hotel room with bottles of alcohol, oxycodone, alprazolam, amphetamine-dextroamphetamine, and tadalafil. When EMS arrives, he appears comatose with pinpoint pupils and oxygen saturation of 80% on room air. He is intubated at the scene and airlifted to the nearest intensive care unit. Body temperature is 95 degrees F (35 degrees C). Creatine phosphokinase is 12,000 U/L. MRI of the brain demonstrates extensive infarcts consistent with acute hypoxic ischemic injury. Which of the following is the likely culprit for his overdose?", "answer": "Opioids", "options": {"A": "Alcohol", "B": "Opioids", "C": "Benzodiazepines", "D": "Amphetamines", "E": "Phosphodiesterase-5 (PDE-5) inhibitors"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying metabolic processes in cells from a mouse model. She identifies certain cells that are unable to generate enough reducing factor for respiratory burst. Increased production of which of the following substances is most likely to be present in these cells?", "answer": "Ribose-5-phosphate from fructose-6-phosphate", "options": {"A": "Ribulose-5-phosphate from glucose-6-phosphate", "B": "Palmitic acid from malonyl-CoA", "C": "Mevalonate from β-hydroxy-β-methylglutaryl-CoA", "D": "Ribose-5-phosphate from fructose-6-phosphate", "E": "6-phosphogluconolactone from glucose-6-phosphate"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old woman comes to the clinic because her period is 4 weeks late, and she is experiencing fatigue and morning nausea. She had her last period almost 8 weeks ago. She is gravida 0 para 0 with previously regular menses and an unremarkable medical history. She had her menarche at the age of 13 years. She has a single sexual partner and does not use contraception. At presentation, her vital signs are within normal limits. Gynecological examination reveals breast and uterine enlargement. There is also cyanosis and softening in the cervical and vaginal regions. Which of the following statements is correct?", "answer": "As the patient’s condition progresses, her estriol levels may rise up to 1000-fold", "options": {"A": "The venous congestion in the patient’s reproductive organs is due to the influence of estrogens", "B": "Estrone has the largest blood concentration among the estrogens in this patient", "C": "Hyperestrogenemia is the most probable cause of this patient’s menstrual delay", "D": "In the patient’s condition, blood estrogen level falls dramatically", "E": "As the patient’s condition progresses, her estriol levels may rise up to 1000-fold"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old gentleman passes away after a car accident. On routine autopsy it is incidentally noted that he has both a ventral and dorsal pancreatic duct. This incidental finding observed by the pathologist is generated due to failure of which of the following embryological processes?", "answer": "Fusion", "options": {"A": "Notochord signaling", "B": "Apoptosis", "C": "Fusion", "D": "Neural crest cell migration", "E": "Stem cell differentiation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old man comes to the physician because of a 6-month history of fatigue and increased sweating at night. He says that he feels “constantly tired” and needs more rest than usual although he sleeps well. In the morning, his sheets are often wet and his skin is clammy. He has not had any sore throat, runny nose, or cough recently. He has not traveled anywhere. Over the past 4 months, he has had a 6.8-kg (15-lb) weight loss, despite having a normal appetite. He does not drink or urinate more than usual. He is 181 cm (5 ft 11 in) tall and weighs 72 kg (159 lb); BMI is 22 kg/m2. His temperature is 37.9°C (100.2°F), pulse is 65/min, and blood pressure is 120/70 mm Hg. Physical examination shows no abnormalities. An HIV screening test and confirmatory test are both positive. The CD4 count is 600 cells/μl and the viral load is 104 copies/mL. Treatment with lamivudine, zidovudine, and indinavir is begun. The patient is at greatest risk for which of the following adverse effects?", "answer": "Urolithiasis\n\"", "options": {"A": "Stevens-Johnson syndrome", "B": "Hypersensitivity reaction", "C": "Pancreatitis", "D": "Chronic kidney disease", "E": "Urolithiasis\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 57-year-old man comes to the physician with a 3-month history of right flank pain. Urinalysis shows 60 RBC/hpf. Renal ultrasound shows a 3 cm, well-defined mass in the upper pole of the right kidney. A photomicrograph of a section of the resected mass is shown. Which of the following is the most likely diagnosis?", "answer": "Oncocytoma", "options": {"A": "Clear cell renal carcinoma", "B": "Oncocytoma", "C": "Nephroblastoma", "D": "Chromophobe renal cell carcinoma", "E": "Angiomyolipoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old man comes to the physician because of a 6-week history of increasing shortness of breath, fatigue, and fever. He has had a cough productive of foul-smelling sputum for 4 weeks. He was hospitalized for alcohol intoxication twice over the past 6 months. He has hypertension and depression. He has smoked one pack of cigarettes daily for 20 years and drinks 6 alcoholic beverages daily. Current medications include ramipril and fluoxetine. He appears malnourished. He is 185 cm (6 ft 1 in) tall and weighs 65.7 kg (145 lb); BMI is 19.1 kg/m2. His temperature is 38.3°C (100.9°F), pulse is 118/min, respirations are 24/min, and blood pressure is 147/96 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 94%. Examination of the chest shows dullness to percussion over the right upper lung field. An x-ray of the chest shows a lung cavity with an air-fluid level and surrounding infiltrate in the right upper lobe of the lung. Which of the following is the most appropriate next step in management?", "answer": "Clindamycin therapy", "options": {"A": "Vancomycin and levofloxacin therapy", "B": "Bronchoscopy and drainage of the lesion", "C": "Sputum cultures", "D": "Metronidazole therapy", "E": "Clindamycin therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 16-year-old girl presents to the emergency department complaining of acute bilateral lower quadrant abdominal pain. She states she is nauseous and reports a 24-hour history of multiple episodes of vomiting. She admits to having unprotected sex with multiple partners. Her temperature is 102.0°F (38.9°C). Physical examination reveals bilateral lower quadrant tenderness. Bimanual pelvic exam reveals cervical exudate and cervical motion tenderness. Her β-HCG is within normal limits. Transvaginal ultrasound reveals a tubular complex lesion located in the right lower quadrant. Which of the following is the most appropriate initial step in the treatment of this patient?", "answer": "Cefoxitin and doxycycline", "options": {"A": "Cefoxitin and doxycycline", "B": "Ceftriaxone and azithromycin", "C": "Levofloxacin and metronidazole", "D": "Metronidazole", "E": "Fluconazole"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man is brought to the emergency department by ambulance after vomiting blood. The patient reports that he only ate a small snack the morning before and had not eaten anything for over 24 hours. At the hospital, the patient is stabilized. He is admitted to a surgical floor and placed on NPO with a nasogastric tube set to intermittent suction. He has been previously diagnosed with liver cirrhosis. An esophagogastroduodenoscopy (EGD) has been planned for the next afternoon. At the time of endoscopy, some pathways were generating glucose to maintain serum glucose levels. Which of the following enzymes catalyzes the irreversible biochemical reaction of this process?", "answer": "Fructose-1,6-bisphosphatase", "options": {"A": "Glycogen phosphorylase", "B": "Enolase", "C": "Glucose-6-phosphate dehydrogenase", "D": "Fructose-1,6-bisphosphatase", "E": "Glyceraldehyde-3-phosphate dehydrogenase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 41-year-old man is admitted to the emergency room after being struck in the abdomen by a large cement plate while transporting it. On initial assessment by paramedics at the scene, his blood pressure was 110/80 mm Hg, heart rate 85/min, with no signs of respiratory distress. On admission, the patient is alert but in distress. He complains of severe, diffuse, abdominal pain and severe weakness. Vital signs are now: blood pressure 90/50 mm Hg, heart rate 96/min, respiratory rate 19/min, temperature 37.4℃ (99.3℉), and oxygen saturation of 95% on room air. His lungs are clear on auscultation. The cardiac exam is significant for a narrow pulse pressure. Abdominal examination reveals a large bruise over the epigastric and periumbilical regions. The abdomen is distended and there is diffuse tenderness to palpation with rebound and guarding, worst in the epigastric region. There is hyperresonance to percussion in the epigastric region and absence of hepatic dullness in the right upper quadrant. Aspiration of the nasogastric tube reveals bloody contents. Focused assessment with sonography for trauma (FAST) shows free fluid in the pelvic region. Evaluation of the perisplenic and perihepatic regions is impossible due to the presence of free air. Aggressive intravenous fluid resuscitation is administered but fails to improve upon the patient’s hemodynamics. Which of the following is the next best step in management?", "answer": "Emergency laparotomy", "options": {"A": "CT scan", "B": "Diagnostic peritoneal lavage (DPL)", "C": "Abdominal ultrasound", "D": "Emergency laparotomy", "E": "Emergency laparoscopy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "The incidence of a relatively benign autosomal recessive disease, X, is 1 in 25 in the population. Assuming that the conditions for Hardy Weinberg Equilibrium are met, what is the probability that a male and female, who are carriers, will have a child expressing the disease?", "answer": "1/4", "options": {"A": "1/4", "B": "1/5", "C": "4/5", "D": "1/25", "E": "8/25"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old male presents to his primary care physician complaining of left hip pain for the past six months. He denies any trauma or recent falls. He is accompanied by his wife who reports that he has experienced progressive hearing loss over the same time period. The patient has also noticed that he is no longer able to fit into his favorite hat even though it previously fit well. A radiograph of the patient’s pelvis is shown. Which of the following laboratory abnormalities is most likely to be found in this patient?", "answer": "Elevated serum alkaline phosphatase", "options": {"A": "Elevated serum parathyroid hormone", "B": "Elevated serum calcium", "C": "Decreased serum calcium", "D": "Elevated serum alkaline phosphatase", "E": "Decreased serum alkaline phosphatase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old male is brought to the emergency department by his roommate for 'strange' behavior over the last 48 hours. The patient states that he is hearing voices speak to him, giving him secret messages and instructions to carry out. He believes that the FBI is following him and spying on his conversations. The patient is concerned that they are listening to these messages and will find out his secrets. The patient's friend does not believe the patient ingested any substance or used any recreational drugs prior to this episode. A negative drug screen is obtained and confirms this. Physical examination does not reveal any abnormalities. Which of the following treatments might best target this patient's symptoms?", "answer": "Risperidone", "options": {"A": "Sertraline", "B": "Risperidone", "C": "Haloperidol", "D": "Chlorpromazine", "E": "Psychotherapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old man presents to the emergency department with left lower quadrant abdominal pain and fever for 1 day. He states during this time frame he has had weight loss and a decreased appetite. The patient had surgery for a ruptured Achilles tendon 1 month ago and is still recovering but is otherwise generally healthy. His temperature is 102°F (38.9°C), blood pressure is 154/94 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is remarkable for an uncomfortable and thin man with left lower quadrant abdominal tenderness without rebound findings. Fecal occult test for blood is positive. Laboratory studies are ordered as seen below.\n\nHemoglobin: 10 g/dL\nHematocrit: 30%\nLeukocyte count: 3,500/mm^3 with normal differential\nPlatelet count: 157,000/mm^3\n\nWhich of the following is the most appropriate next step in management?", "answer": "CT abdomen", "options": {"A": "Ceftriaxone and metronidazole", "B": "Ciprofloxacin and metronidazole", "C": "Colonoscopy", "D": "CT abdomen", "E": "MRI abdomen"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Six days after falling in the shower, a 75-year-old man with COPD is brought to the emergency department because of progressively worsening left-sided chest pain and shortness of breath. He has smoked one pack of cigarettes daily for 50 years. His temperature is 36.5°C (97.7°F), pulse is 110/min, respirations are 30/min, and blood pressure is 115/58 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 88%. Examination shows dullness to percussion and decreased fremitus over the left lung base. There are faint expiratory wheezes throughout the lungs. An x-ray of the chest is shown. Which of the following is the most likely cause of this patient’s current condition?", "answer": "Blood in the pleural space", "options": {"A": "Air between the pleura and chest wall", "B": "Bacteria in the pulmonary parenchyma", "C": "Fluid in alveoli", "D": "Neoplastic cells in the bronchi", "E": "Blood in the pleural space"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-month-old boy is brought to the emergency department by his mother for several hours of crying and severe abdominal pain, followed by dark and bloody stools in the last hour. The mother reports that she did not note any vomiting or fevers leading up to this incident. She does report that the boy and his 7-year-old sister recently had “stomach bugs” but that both have been fine and that the sister has gone back to school. The boy was born by spontaneous vaginal delivery at 39 weeks and 5 days after a normal pregnancy. His temperature is 100.4°F (38.0°C), blood pressure is 96/72 mmHg, pulse is 90/min, respirations are 22/min. Which of the following was most likely to play a role in the pathogenesis of this patient’s disease?", "answer": "Hyperplasia of Peyer patches", "options": {"A": "Embolism to the mesenteric vessels", "B": "Failure of neural crest migration", "C": "Hyperplasia of Peyer patches", "D": "Intestinal mass", "E": "Vascular malformation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old man comes to the physician because of severe lower back pain for the past 2 days. The pain is constant and non-radiating, and he describes it as 7 out of 10 in intensity. The pain began after he helped a friend move into a new apartment. Three weeks ago, he was diagnosed with urethritis and was treated with azithromycin and ceftriaxone. He has a history of intravenous heroin use. He takes no medications. His temperature is 37°C (98.6°F), pulse is 98/min, and blood pressure is 128/90 mm Hg. Examination shows old track marks on the cubital fossae bilaterally. His lumbar paraspinal muscles are firm and tense on palpation. There is no midline spinal tenderness. Flexing the hip and extending the knee while raising the leg to 70° does not cause any pain. Urinalysis shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Analgesia and regular activity", "options": {"A": "Analgesia and regular activity", "B": "MRI of the spine", "C": "Measurement of serum HLA-B27", "D": "Broad-spectrum antibiotic therapy", "E": "Spinal traction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man with known coronary artery disease presents to the ED with epigastric pain, worsening fatigue, and melena. He takes aspirin and rosuvastatin, but took ibuprofen over the past two weeks for lower back pain. He denies nausea, vomiting, hematemesis, chest pain, fever, and weight loss. Sitting blood pressure is 100/70 mmHg and pulse is 90/min, but standing blood pressure is 85/60 mmHg and pulse is 110/min. Airway is patent. His hands feel cold and clammy. Abdominal exam confirms epigastric pain, but no rebound tenderness or hyperpercussion. Despite 2 liters of lactated Ringer's, the blood pressure and pulse have not changed. What hemoglobin (Hb) threshold should be considered if packed red blood cell (pRBC) transfusion is ordered in this patient?", "answer": "threshold does not matter", "options": {"A": "threshold does not matter", "B": "< 10", "C": "< 9", "D": "< 8", "E": "< 7"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 61-year-old farmer comes to the physician because of a 3-month history of progressively worsening cough and shortness of breath. He has had a 7.5-kg (16.5-lb) weight loss during this period. He smokes occasionally and does not drink alcohol. Physical examination shows clubbing of the fingers. End-inspiratory crackles are heard in both lower lung fields. X-ray of the chest shows bilateral reticulonodular densities with interstitial fibrosis. Histologic examination of a lung biopsy specimen shows noncaseating granulomas in the interstitium. Which of the following is the most likely underlying mechanism of this patient's condition?", "answer": "IgG-mediated immune complex deposition", "options": {"A": "Aspergillus-induced eosinophil release", "B": "Silica-induced macrophage activation", "C": "IgG-mediated immune complex deposition", "D": "IgE-mediated histamine release", "E": "Elastase-mediated parenchymal destruction"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man comes to the emergency department because he has been having problems seeing over the last week. He says that he has been seeing specks in his vision and his vision also becomes blurry when he tries to focus on objects. He says that he cannot recall anything that may have precipitated this; however, he has been homeless for several months. His CD4+ cell count is 27 cells/mL so he is started on a new medication. Notably, this drug has the following properties when mixed with various proteins:\n\nDrug alone - drug remains unphosphorylated\nDrug and HSV proteins - drug remains unphosphorylated\nDrug and CMV proteins - drug remains unphosphorylated\nDrug and human proteins - drug is phosphorylated\n\nWhich of the following drugs is most consistent with this set of findings?", "answer": "Cidofovir", "options": {"A": "Acyclovir", "B": "Cidofovir", "C": "Foscarnet", "D": "Ganciclovir", "E": "Oseltamivir"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "One day after a 4700-g (10-lb 6-oz) male newborn is delivered to a 28-year-old primigravid woman, the newborn has bluish discoloration of the lips and fingernails. His temperature is 37.3°C (99.1°F), pulse is 166/min, respirations are 63/min, and blood pressure is 68/44 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 81%. Examination shows central cyanosis. A grade 2/6 holosystolic murmur is heard over the left lower sternal border. A single second heart sound is present. Supplemental oxygen does not improve cyanosis. An x-ray of the chest shows an enlarged cardiac silhouette with a narrowed mediastinum. Further evaluation of the mother is most likely to show which of the following?", "answer": "Elevated hemoglobin A1c", "options": {"A": "Increased serum TSH", "B": "Prenatal alcohol consumption", "C": "Prenatal lithium intake", "D": "Positive rapid plasma reagin test", "E": "Elevated hemoglobin A1c"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 36-year-old woman gravida 5, para 4 was admitted at 31 weeks of gestation with worsening fatigue and shortness of breath on exertion for the past month. She also has nausea and loss of appetite. No significant past medical history. The patient denies any smoking history, alcohol or illicit drug use. Her vital signs include: blood pressure 110/60 mm Hg, pulse 120/min, respiratory rate 22/min and temperature 35.1℃ (97.0℉). A complete blood count reveals a macrocytosis with severe pancytopenia, as follows:\nHb 7.2 g/dL\nRBC 3.6 million/uL\nWBC 4,400/mm3\nNeutrophils 40%\nLymphocytes 20%\nPlatelets 15,000/mm3\nMCV 104 fL\nReticulocytes 0.9%\nSerum ferritin and vitamin B12 levels were within normal limits. There was an elevated homocysteine level and a normal methylmalonic acid level. Which of the following is the most likely diagnosis in this patient?", "answer": "Folate deficiency", "options": {"A": "Vitamin B12 deficiency", "B": "Iron deficiency anemia", "C": "Folate deficiency", "D": "Normal pregnancy", "E": "Aplastic anemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 78-year-old Caucasian male actor presents to your office complaining of a dry, non-productive cough. He has a history of hypertension, diabetes, and coronary artery disease and he follows a complicated regimen of medications to treat his multiple co-morbidities. Which of the following medications is most likely to be associated with his chief complaint?", "answer": "Lisinopril", "options": {"A": "Aspirin", "B": "Lisinopril", "C": "Hydrochlorothiazide", "D": "Metoprolol", "E": "Nifedipine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator studying viral mutation isolates a virus strain from the gastric contents of an infant with gastroenteritis. This virus has a nonenveloped RNA genome with 11 segments and a helical symmetrical capsid. The investigator finds that if 2 strains of this virus coinfect a single host cell, some of the resulting viral progeny have genome segments derived from both parental viruses. The observed phenomenon is most likely also seen in which of the following viral families?", "answer": "Orthomyxoviruses", "options": {"A": "Flaviviruses", "B": "Orthomyxoviruses", "C": "Caliciviruses", "D": "Picornaviruses", "E": "Retroviruses"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Please refer to the summary above to answer this question\nAdministration of which of the following is most likely to improve this patient's current symptoms?\"\n\"Patient information\nAge: 82 years\nGender: M, self-identified\nEthnicity: Caucasian\nSite of care: office\nHistory\nReason for Visit/Chief Concern: “I have been getting these large bruises on my arms and legs.”\nHistory of Present Illness:\nhis wife noticed 6 weeks ago that he had bruising on the bilateral lower extremities\nadditional ecchymoses developed on the bilateral upper extremities 2 weeks ago\nfeels increasingly fatigued\nhas joint pain of the elbows, hips, and knees\nwas unable to complete his final cycle of chemotherapy for non-small cell lung carcinoma because of the pain\nhas not had trauma or prior episodes of significant bleeding\nPast Medical History:\nhypertension\nbenign prostatic hyperplasia\nosteoarthritis\nnon-small cell lung carcinoma: treated with resection, currently undergoing adjuvant chemotherapy\nSocial History:\nlives with his wife\nhas been eating sparingly\nhas smoked 2 packs of cigarettes daily for 60 years\nMedications:\namlodipine, lisinopril, tamsulosin, acetaminophen; currently undergoing cisplatin-based chemotherapy\nAllergies:\nno known drug allergies\nPhysical Examination\nTemp Pulse Resp. BP O2 Sat Ht Wt BMI\n36.6°C\n(97.8°F)\n88/min 20/min 128/83 mm Hg 96%\n175 cm\n(5 ft 9 in)\n53 kg\n(117 lb)\n17 kg/m2\nAppearance: pale, tired-appearing, cachectic man, sitting in a wheelchair\nHEENT: mild mucosal bleeding\nPulmonary: diminished breath sounds in the left lower lung field; moderate inspiratory wheezes bilaterally; no rales or rhonchi\nCardiac: normal S1 and S2; no murmurs, rubs, or gallops\nAbdominal: soft; nontender; nondistended; normal bowel sounds\nExtremities: symmetrically cool; no edema\nSkin: coiled hairs with perifollicular hemorrhages; multiple ecchymoses of the bilateral upper and lower extremities\nNeurologic: symmetrically decreased sensation to pinprick, vibration, and fine touch in the distal lower extremities\"", "answer": "Vitamin C", "options": {"A": "Vitamin C", "B": "Vitamin A", "C": "Vitamin B12", "D": "Vitamin B6", "E": "Vitamin K\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 53-year-old woman comes to the emergency department because of weakness and abdominal pain for 24 hours. She has had three bowel movements with dark stool during this period. She has not had vomiting and has never had such episodes in the past. She underwent a tubal ligation 15 years ago. She has chronic lower extremity lymphedema, osteoarthritis, and type 2 diabetes mellitus. Her father died of colon cancer at the age of 72 years. Current medications include metformin, naproxen, and calcium with vitamin D3. She had a screening colonoscopy at 50 years of age which was normal. She appears pale and diaphoretic. Her temperature is 36°C (96.8°F), pulse is 110/min, respirations are 20/min, and blood pressure is 90/50 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. The abdomen is soft and nondistended with mild epigastric tenderness. Rectal exam shows tarry stool. Two large bore IV lines are placed and fluid resuscitation with normal saline is initiated. Which of the following is the most appropriate next step in management?", "answer": "Esophagogastroduodenoscopy", "options": {"A": "CT scan of the abdomen with contrast", "B": "Diagnostic laparoscopy", "C": "Colonoscopy", "D": "Flexible sigmoidoscopy", "E": "Esophagogastroduodenoscopy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old woman with no significant past medical, past surgical, or family history presents with new symptoms of chest pain, an oral rash, and pain with swallowing. She lost her husband several months earlier and has moved into an elderly assisted living community. She states that her symptoms began several weeks earlier. Physical examination reveals numerous white plaques on her buccal mucosa and tongue. What is the next step in the patient’s management?", "answer": "CD4 count", "options": {"A": "Single contrast esophagram with barium sulfate contrast", "B": "Modified barium swallow", "C": "Denture fitting assessment", "D": "CD4 count", "E": "Single contrast esophagram with water soluble iodine contrast"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 33-year-old man presents to the emergency department with a fever and fatigue. He states that he has not felt well since he returned from a hiking trip in Alabama. He is generally healthy and has no other medical conditions. His temperature is 101°F (38.3°C), blood pressure is 127/85 mmHg, pulse is 108/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam including a full dermatologic inspection is unremarkable. Laboratory studies are ordered as seen below.\n\nHemoglobin: 13 g/dL\nHematocrit: 39%\nLeukocyte count: 2,200/mm^3 with normal differential\nPlatelet count: 77,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 24 mEq/L\nBUN: 19 mg/dL\nGlucose: 98 mg/dL\nCreatinine: 1.3 mg/dL\nCa2+: 10.2 mg/dL\nAST: 92 U/L\nALT: 100 U/L\n\nWhich of the following is the most likely diagnosis?", "answer": "Ehrlichiosis", "options": {"A": "Babesiosis", "B": "Ehrlichiosis", "C": "Influenza", "D": "Lyme disease", "E": "Rocky mountain spotted fever"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 42-year-old woman comes to the physician for evaluation of a 6-month history of irregular menstrual periods. Her last period was 3 months ago. Previously, her periods occurred at regular 28-day intervals and lasted 4–5 days with moderate flow. She has also noticed breast tenderness and scant nipple discharge. She has type 2 diabetes mellitus and refractory bipolar I disorder. Current medications include metformin, glipizide, lithium, and risperidone. Physical examination shows no abnormalities. A urine pregnancy test is negative. Which of the following is the most likely cause of the changes in her menstrual cycle?", "answer": "Blockade of pituitary dopamine receptors", "options": {"A": "Dysregulation of theca and granulosa cell steroidogenesis", "B": "Reduced renal elimination of prolactin", "C": "Impaired production and release of thyroxine", "D": "Failure of ovaries to respond to gonadotropins", "E": "Blockade of pituitary dopamine receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 15-year-old boy is brought to the physician by his mother for a well-child examination. He recently stopped attending his swim classes. The patient is at the 97th percentile for height and the 50th percentile for weight. Examination shows decreased facial hair, bilateral breast enlargement, and long extremities. Genital examination shows scant pubic hair, small testes, and a normal-sized penis. Further evaluation is most likely to show which of the following karyotypes?", "answer": "47,XXY", "options": {"A": "47,XYY", "B": "46,XX/46,XY", "C": "45,XO", "D": "47,XXY", "E": "45,XO/46,XX"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 14-year-old girl comes to the physician for exertional leg pain. The pain began last week when she started jogging to lose weight. She is at the 5th percentile for height and 80th percentile for weight. Physical examination shows a broad neck with bilateral excess skin folds that extend to the shoulders, as well as a low-set hairline and ears. There is an increased carrying angle when she fully extends her arms at her sides. Pulses are palpable in all extremities; lower leg pulses are delayed. Which of the following additional findings is most likely in this patient?", "answer": "Ovarian dysgenesis", "options": {"A": "Ovarian dysgenesis", "B": "Absent uterus", "C": "Mitral valve prolapse", "D": "Triphalangeal thumb", "E": "Horseshoe adrenal gland"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-year-old boy is brought to the physician because of recurrent respiratory infections and difficulty walking for 2 months. Physical examination shows numerous telangiectasias on the nose, ears, and neck. There is overshoot on the finger-to-nose test. He has a narrow-based gait. Genetic analysis shows a nonsense mutation in the ataxia-telangiectasia gene (ATM gene). Sequencing of the encoded truncated protein shows that the C-terminal amino acid is not methionine but another amino acid. The last correctly incorporated amino acid is most likely encoded by which of the following tRNA anticodons?", "answer": "3'ACC5'", "options": {"A": "3'AUU5'", "B": "3'UAC5'", "C": "3'ACC5'", "D": "3'ACU5'", "E": "3'AUC5'"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 8-year-old child with “elfin” facial features is very friendly with strangers. He has a history of mild mental retardation, and a hemizygous deletion on chromosome 7q11.23, that includes a portion of the elastin gene. Which of the following is most likely true in this patient?", "answer": "Symptoms may develop secondary to left ventricular outflow tract obstruction", "options": {"A": "Carpopedal spasm induced by sphygmomanometer inflation", "B": "Vitamin D supplementation is recommended", "C": "Holosystolic murmur heard at the apex with radiation to the axilla", "D": "Symptoms may develop secondary to left ventricular outflow tract obstruction", "E": "This patient is less likely to experience angina"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A study aimed to evaluate the relationship between inflammatory markers and lipid metabolism in individuals with rheumatoid arthritis (RA) recruited 252 patients with RA in a tertiary care hospital. Fasting blood samples were taken for lipid profiling and for the assessment of inflammatory markers such as C-reactive protein (CRP) and erythrocyte sedimentation rate. The relationship between CRP and total cholesterol was assessed using Pearson’s correlation coefficient. A scatter plot between CRP and total cholesterol can be seen in the picture. Based on the scatter plot, which of the following can be correctly concluded about the value of the Pearson correlation coefficient, r, for CRP and total cholesterol?", "answer": "r value lies between 0 and -1", "options": {"A": "r value is exactly +1", "B": "r value lies between 0 and +1", "C": "r value is exactly 0", "D": "r value lies between 0 and -1", "E": "r value is exactly -1"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old woman, gravida 1, para 0, at 33 weeks' gestation comes to her doctor for a routine visit. Her pregnancy has been uncomplicated. She has systemic lupus erythematosus and has had no flares during her pregnancy. She does not smoke cigarettes, drink alcohol, or use illicit drugs. Current medications include iron, vitamin supplements, and hydroxychloroquine. Her temperature is 37.2°C (98.9°F), pulse is 70/min, respirations are 17/min, and blood pressure is 134/70 mm Hg. She appears well. Physical examination shows no abnormalities. Ultrasound demonstrates fetal rhythmic breathing for > 30 seconds, amniotic fluid with deepest vertical pocket of 1 cm, one distinct fetal body movement over 30 minutes, and no episodes of extremity extension over 30 minutes. Nonstress test is reactive and reassuring. Which of the following is the next best step in management?", "answer": "Induction of labor", "options": {"A": "Perform cesarean delivery", "B": "Discontinue hydroxychloroquine and continue close monitoring", "C": "Administer corticosteroids and continue close monitoring", "D": "Induction of labor", "E": "Reassurance with expectant management"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 15-year-old girl is brought to the physician by her parents because she has not had menstrual bleeding for the past 2 months. Menses had previously occurred at irregular 15–45 day intervals with moderate to heavy flow. Menarche was at the age of 14 years. Eight months ago, she was diagnosed with bipolar disorder and treatment with risperidone was begun. Her parents report that she is very conscious of her weight and appearance. She is 168 cm (5 ft 5 in) tall and weighs 76 kg (168 lb); BMI is 26.9 kg/m2. Pelvic examination shows a normal vagina and cervix. Serum hormone studies show:\nProlactin 14 ng/mL\nFollicle-stimulating hormone 5 mIU/mL\nLuteinizing hormone 5.2 mIU/mL\nProgesterone 0.9 ng/mL (follicular N <3; luteal N >3–5)\nTestosterone 2.7 nmol/L (N <3.5)\nA urine pregnancy test is negative. Which of the following is the most likely cause of her symptoms?\"", "answer": "Anovulatory cycles", "options": {"A": "Primary ovarian insufficiency", "B": "Anovulatory cycles", "C": "Uterine leiomyomas", "D": "Adverse effect of medication", "E": "Self-induced vomiting"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man is brought to the emergency department because of headaches, vertigo, and changes to his personality for the past few weeks. He was diagnosed with HIV 14 years ago and was started on antiretroviral therapy at that time. Medical records from one month ago indicate that he followed his medication schedule inconsistently. Since then, he has been regularly taking his antiretroviral medications and trimethoprim-sulfamethoxazole. His vital signs are within normal limits. Neurological examination shows ataxia and apathy. Mini-Mental State Examination score is 15/30. Laboratory studies show:\nHemoglobin 12.5 g/dL\nLeukocyte count 8400/mm3\nSegmented neutrophils 80%\nEosinophils 1%\nLymphocytes 17%\nMonocytes 2%\nCD4+ T-lymphocytes 90/μL\nPlatelet count 328,000/mm3\nAn MRI of the brain with contrast shows a solitary ring-enhancing lesion involving the corpus callosum and measuring 4.5 cm in diameter. A lumbar puncture with subsequent cerebrospinal fluid analysis shows slight pleocytosis, and PCR is positive for Epstein-Barr virus DNA. Which of the following is the most likely diagnosis?\"", "answer": "CNS lymphoma", "options": {"A": "AIDS dementia", "B": "CNS lymphoma", "C": "Progressive multifocal leukoencephalopathy", "D": "Bacterial brain abscess", "E": "Glioblastoma\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old man comes to the physician because of right shoulder pain that began after he repainted his house 1 week ago. Physical examination shows right subacromial tenderness. The pain is reproduced when the patient is asked to abduct the shoulder against resistance with the arm flexed forward by 30° and the thumb pointing downwards. The tendon of which of the following muscles is most likely to be injured in this patient?", "answer": "Supraspinatus", "options": {"A": "Supraspinatus", "B": "Subscapularis", "C": "Infraspinatus", "D": "Teres minor", "E": "Deltoid"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 19-year-old woman presents to the primary care clinic to establish care. She has no acute complaints or concerns. Upon further questioning, she shares that she gets frequent nosebleeds and often bleeds from her gums a little after brushing her teeth. She also typically has relatively heavy menstrual periods, soaking eight tampons per day. She has not had any serious bleeding events, and she has never had a blood transfusion. Physical exam is unremarkable. A complete blood count shows mild anemia with a normal platelet count. Which of the following is the next best step in the management of this patient?", "answer": "Perform platelet aggregation tests", "options": {"A": "Perform bone marrow biopsy", "B": "Start corticosteroids", "C": "Start desmopressin", "D": "Start intravenous immunoglobulin", "E": "Perform platelet aggregation tests"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 23-year-old woman is brought to the physician by her father because of irritability, mood swings, and difficulty sleeping over the past 10 days. A few days ago, she quit her job and spent all of her savings on supplies for a “genius business plan.” She has been energetic despite sleeping only 1–2 hours each night. She was diagnosed with major depressive disorder 2 years ago. Mental status examination shows pressured speech, a labile affect, and flight of ideas. Throughout the examination, she repeatedly states “I feel great, I don't need to be here.” Urine toxicology screening is negative. Which of the following is the most likely diagnosis?", "answer": "Bipolar disorder type I", "options": {"A": "Delusional disorder", "B": "Bipolar disorder type II", "C": "Bipolar disorder type I", "D": "Schizoaffective disorder", "E": "Attention-deficit hyperactivity disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 6-year-old girl is brought to the physician by her parents because of slowed growth and fatigue. Over the past year, she went from average height for her age group to the shortest in her class. She has also been having more problems concentrating in class and is less interested in playing. She has not had any change in appetite or diet. She is at the 10th percentile for height and the 90th percentile for weight. Vital signs are within normal limits. There is a nontender mass palpated on the anterior cervical examination. Serum laboratory studies show thyroid-stimulating hormone level of 6.7 μU/mL. Further evaluation is most likely to show which of the following findings?", "answer": "Lymphocytic infiltration on fine needle aspiration", "options": {"A": "Lymphocytic infiltration on fine needle aspiration", "B": "Positive serum thyroid stimulating hormone receptor antibody", "C": "Psammoma bodies on fine needle aspiration", "D": "Increased uptake on I-131 scan in a discrete 1-cm nodule", "E": "Low urine iodine levels\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 5-year-old non-verbal child with a history of autism is brought into the emergency department by his grandmother. The patient’s grandmother is concerned her grandchild is being abused at home. The patient lives in an apartment with his mother, step-father, and two older brothers in low-income housing. The department of social services has an open case regarding this patient and his family. The patient is afebrile. His vital signs include: blood pressure 97/62 mm Hg, pulse 175/min, respiratory rate 62/min. Physical examination reveals a malnourished and dehydrated child in dirty and foul-smelling clothes. Which one of the following people is most likely abusing this patient?", "answer": "Mother", "options": {"A": "Mother", "B": "Step-father", "C": "Brother", "D": "Neighbor", "E": "Stranger"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "BACKGROUND:\nAldosterone blockade reduces mortality and morbidity among patients with severe heart failure. We conducted a double-blind, placebo-controlled study evaluating the effect of eplerenone, a selective aldosterone blocker, on morbidity and mortality among patients with acute myocardial infarction complicated by left ventricular dysfunction and heart failure.\nMETHODS:\nPatients were randomly assigned to eplerenone (25 mg per day initially, titrated to a maximum of 50 mg per day; 3,319 patients) or placebo (3,313 patients) in addition to optimal medical therapy. The study continued until 1,012 deaths occurred. The primary endpoints were death from any cause, death from cardiovascular causes, hospitalization for a heart failure exacerbation, acute myocardial infarction, stroke, or ventricular arrhythmia.\nRESULTS:\nDuring a mean follow-up of 16 months, there were 478 deaths in the eplerenone group and 554 deaths in the placebo group (relative risk, 0.85; 95% confidence interval, 0.75 to 0.96; p=0.008). Of these deaths, 407 in the eplerenone group and 483 in the placebo group were attributed to cardiovascular causes (relative risk, 0.83; 95% confidence interval, 0.72 to 0.94; p=0.005). The rate of the other primary endpoints, death from cardiovascular causes or hospitalization for cardiovascular events, was reduced by eplerenone (relative risk, 0.87; 95% confidence interval, 0.79 to 0.95; p=0.002), as was the secondary endpoint of death from any cause or any hospitalization (relative risk, 0.92; 95% confidence interval, 0.86 to 0.98; p=0.02). There was also a reduction in the rate of sudden death from cardiac causes (relative risk, 0.79; 95% confidence interval, 0.64 to 0.97; p=0.03). The rate of serious hyperkalemia was 5.5% in the eplerenone group and 3.9% in the placebo group (p=0.002), whereas the rate of hypokalemia was 8.4% in the eplerenone group and 13.1% in the placebo group (p<0.001).\nWhich of the following represents the relative risk reduction (RRR) in all-cause mortality, the primary endpoint, in patients supplemented with eplerenone?", "answer": "0.15", "options": {"A": "0.15", "B": "0.17", "C": "0.13", "D": "0.08", "E": "0.21"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 20-year-old woman comes to the physician for the evaluation of fatigue and low energy levels for 2 months. She has not had fever or weight changes. She has no history of serious illness except for an episode of infectious mononucleosis 4 weeks ago. Menses occur at regular 28-day intervals and last 5 days with moderate flow. Her last menstrual period was 3 weeks ago. Her mother has Hashimoto's thyroiditis. Vital signs are within normal limits. Examination shows pale conjunctivae, inflammation of the corners of the mouth, and brittle nails. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 10.3 g/dL\nMean corpuscular volume 74 μm3\nPlatelet count 280,000/mm3\nLeukocyte count 6,000/mm3\nWhich of the following is the most appropriate initial step in management?\"", "answer": "Iron studies", "options": {"A": "Iron studies", "B": "Vitamin B12 levels", "C": "Hemoglobin electrophoresis", "D": "Peripheral blood smear", "E": "Direct Coombs test"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-year-old boy is brought to the clinic by his father for complaints of “constant irritation.” His father explains that ever since his divorce with the son’s mother last year he has noticed increased irritability in his son. \"He has been skipping out on his baseball practices which he has always enjoyed,” his dad complains. After asking the father to step out, the patient reports trouble concentrating at school and has been staying up late “just thinking about stuff.” When probed further, he states that he “feels responsible for his parents' divorce because he was being rebellious.” What is the best treatment for this patient at this time?", "answer": "Escitalopram", "options": {"A": "Buspirone", "B": "Escitalopram", "C": "Quetiapine", "D": "Methylphenidate", "E": "Venlafaxine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 12-year-old boy is brought to the emergency room by his mother with complaints of abdominal pain and fever that started 24 hours ago. On further questioning, the mother says that her son vomited twice and has constipation that started approximately 1 and one-half days ago. The medical history is benign. The vital signs are as follows: heart rate 103/min, respiratory rate of 20/min, temperature 38.7°C (101.66°F), and blood pressure 109/69 mm Hg. On physical examination, there is severe right lower quadrant abdominal tenderness on palpation. Which of the following is the most likely cause for this patient’s symptoms?", "answer": "Luminal obstruction due to a fecalith", "options": {"A": "Luminal obstruction due to a fecalith", "B": "Twisting of testes on its axis, hampering the blood supply", "C": "Ascending infection of the urinary tract", "D": "Luminal obstruction preventing passage of gastrointestinal contents", "E": "Immune-mediated vasculitis associated with IgA deposition"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old man comes to the emergency department because of a wound in his foot. Four days ago, he stepped on a nail while barefoot at the beach. Examination of the plantar surface of his right foot shows a purulent puncture wound at the base of his second toe with erythema and tenderness of the surrounding skin. The afferent lymphatic vessels from the site of the lesion drain directly into which of the following groups of regional lymph nodes?", "answer": "Superficial inguinal", "options": {"A": "Deep inguinal", "B": "Superficial inguinal", "C": "External iliac", "D": "Popliteal", "E": "Anterior tibial"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old male is admitted to the ICU for severe hypertension complicated by a headache. The patient has a past medical history of insulin-controlled diabetes, hypertension, and hyperlipidemia. He smokes 2 packs of cigarettes per day. He states that he forgot to take his medications yesterday and started getting a headache about one hour ago. His vitals on admission are the following: blood pressure of 160/110 mmHg, pulse 95/min, temperature 98.6 deg F (37.2 deg C), and respirations 20/min. On exam, the patient has an audible abdominal bruit. After administration of antihypertensive medications, the patient has a blood pressure of 178/120 mmHg. The patient reports his headache has increased to a 10/10 pain level, that he has trouble seeing, and he can't move his extremities. After stabilizing the patient, what is the best next step to diagnose the patient's condition?", "answer": "CT head without intravenous contrast", "options": {"A": "CT head with intravenous contrast", "B": "CT head without intravenous contrast", "C": "MRI head with intravenous constrast", "D": "MRI head without intravenous constrast", "E": "Doppler ultrasound of the carotids"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 23-year-old nulligravida presents for evaluation 5 weeks after her last menstrual period. Her previous menstruation cycle was regular, and her medical history is benign. She is sexually active with one partner and does not use contraception. A urine dipstick pregnancy test is negative. The vital signs are as follows: blood pressure 120/80 mm Hg, heart rate 71/min, respiratory rate 13/min, and temperature 36.8°C (98.2°F). The physical examination is notable for breast engorgement, increased pigmentation of the nipples, and linea alba. The gynecologic examination demonstrates cervical and vaginal cyanosis.\nMeasurement of which of the following substances is most appropriate in this case?", "answer": "Blood human chorionic gonadotropin", "options": {"A": "Blood estriol", "B": "Urinary human chorionic gonadotropin", "C": "Blood progesterone", "D": "Urinary estrogen metabolites", "E": "Blood human chorionic gonadotropin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A scientist wants to extract mRNA from a cell line of interest, amplify a specific mRNA, and insert it into a plasmid so that he can transfect it into a cell in order to over-express that protein. Which of the following proteins is required for the first step of amplification of this mRNA?", "answer": "Reverse transcriptase", "options": {"A": "Taq DNA polymerase", "B": "Ligase", "C": "Reverse transcriptase", "D": "Restriction digestion enzymes", "E": "RNA polymerase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 33-year-old pregnant woman undergoes a routine quad-screen during her second trimester. The quad-screen results demonstrate the following: decreased alpha-fetoprotein, increased Beta-hCG, decreased estriol, and increased inhibin A. A presumptive diagnosis is made based upon these findings and is later confirmed with genetic testing. After birth, this child is at greatest risk for which of the following hematologic malignancies?", "answer": "Acute lymphoblastic leukemia", "options": {"A": "Chronic lymphocytic leukemia", "B": "Hairy cell leukemia", "C": "Acute promyelocytic leukemia", "D": "Acute lymphoblastic leukemia", "E": "Chronic myelogenous leukemia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2-year-old girl is brought to her pediatrician’s office with intermittent and severe stomach ache and vomiting for the last 2 days. Last week the whole family had a stomach bug involving a few days of mild fever, lack of appetite, and diarrhea but they have all made a full recovery since. This current pain is different from the type she had during infection. With the onset of pain, the child cries and kicks her legs up in the air or pulls them to her chest. The parents have also observed mucousy stools and occasional bloody stools that are bright red and mucousy. After a while, the pain subsides and she returns to her normal activity. Which of the following would be the next step in the management of this patient?", "answer": "Air enema", "options": {"A": "Air enema", "B": "Abdominal CT scan", "C": "Abdominal radiograph", "D": "Surgical reduction", "E": "Observe for 24 hours"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old woman presents to the emergency department with a 3-day history of fever and headache. She says that the symptoms started suddenly after she woke up 3 days ago, though she has been feeling increasingly fatigued over the last 5 months. On presentation, her temperature is 102°F (38.9°C), blood pressure is 117/74 mmHg, pulse is 106/min, and respirations are 14/min. Physical exam reveals diffuse petechiae and conjunctival pallor and selected laboratory results are shown as follows:\n\nBleeding time: 11 minutes\nPlatelet count: 68,000/mm^3\nLactate dehydrogenase: 105 U/L\n\nWhich of the following would also most likely be true for this patient?", "answer": "Increased serum von Willebrand factor multimers", "options": {"A": "Decreased platelet aggregation on peripheral blood smear", "B": "Immune production of anti-platelet antibodies", "C": "Increased prothrombin time and partial thromboplastin time", "D": "Increased serum von Willebrand factor multimers", "E": "Large platelets on peripheral blood smear"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old healthy college student presents to the clinic with her boyfriend complaining of a productive cough with rust-colored sputum associated with breathlessness for the past week. She also reports symptoms of the common cold which began about 1 week ago. She reports that her weekly routine has not changed despite feelings of being sick and generally weak. The vitals signs include a blood pressure 120/80 mm Hg, pulse rate 68/min, respiratory rate 12/min, and temperature 36.6°C (97.9°F). On pulmonary examination, inspiratory crackles were heard. The cardiac examination revealed an S3 sound but was otherwise normal. A chest X-ray was performed and is shown in the picture below. What medication is known to be associated with the same condition that she is suffering from?", "answer": "Anthracyclines", "options": {"A": "Quinidine", "B": "Anthracyclines", "C": "Metoprolol", "D": "Vincristine", "E": "Cisplatin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old Caucasian woman presents to the physician with urinary frequency, urgency, and pelvic pain for 1 week. She has poor sleep quality because her symptoms persist throughout the night, as well as the day. Her pain partially subsides with urination. She does not have dysuria or urinary incontinence. Her menstrual cycles are regular. Over the past 6 months, she has had several similar episodes, each lasting 1–2 weeks. She has been relatively symptom-free between episodes. Her symptoms began 6 months ago after an established diagnosis of cystitis, for which she was treated with appropriate antibiotics. Since that time, urine cultures have consistently been negative. Her past history is significant for a diagnosis of fibromyalgia 2 years ago, multiple uterine fibroids, irritable bowel syndrome, and depression. She takes tramadol occasionally and sertraline daily. The vital signs are within normal limits. The neurologic examination showed no abnormalities. Examination of the abdomen, pelvis, and rectum was unremarkable. Cystoscopy reinspection after full distension and drainage reveals small, petechial hemorrhages throughout the bladder except for the trigone. Which of the following is the most appropriate next step in management?", "answer": "Behavior modification", "options": {"A": "Amitriptyline", "B": "Behavior modification", "C": "Bladder hydrodistention", "D": "Intravesical dimethyl sulfoxide", "E": "Oxybutynin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A mother brings her 6-month-old boy to the emergency department. She reports that her son has been breathing faster than usual for the past 2 days, and she has noted occasional wheezing. She states that prior to the difficulty breathing, she noticed some clear nasal discharge for several days. The infant was born full-term, with no complications, and no significant medical history. His temperature is 100°F (37.8°C), blood pressure is 60/30 mmHg, pulse is 120/min, respirations are 40/min, and oxygen saturation is 95% on room air. Physical exam reveals expiratory wheezing, crackles diffusely, and intercostal retractions. The child is currently playing with toys. Which of the following is the most appropriate next step in management?", "answer": "Monitoring", "options": {"A": "Albuterol", "B": "Azithromycin and ceftriaxone", "C": "Chest radiograph", "D": "Intubation", "E": "Monitoring"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A patient presents to the emergency room in an obtunded state. The patient is a known nurse within the hospital system and has no history of any medical problems. A finger stick blood glucose is drawn showing a blood glucose of 25 mg/dL.\n\nThe patient's daughter immediately arrives at the hospital stating that her mother has been depressed recently and that she found empty syringes in the bathroom at the mother's home. Which of the following is the test that will likely reveal the diagnosis?", "answer": "C-peptide level", "options": {"A": "Genetic testing", "B": "C-peptide level", "C": "24 hr cortisol", "D": "Fasting blood glucose", "E": "Urine metanephrines"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 38-year-old project manager is told by her boss that her team will need to work on an additional project in the coming week for a very important client. This frustrates the woman, who already feels that she works too many hours. Instead of discussing her feelings directly with her boss, the woman leaves a voice message for her boss the next day and deceitfully says she cannot come to work for the next week because of a family emergency. Which of the following psychological defense mechanisms is this individual demonstrating?", "answer": "Passive aggression", "options": {"A": "Acting out", "B": "Displacement", "C": "Passive aggression", "D": "Malingering", "E": "Blocking"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 83-year-old woman with fever, malaise, and cough for the past 24 hours is brought to the emergency department. She lives in an assisted living facility, and several of her neighbors have had similar symptoms. She has a past medical history of hypertension treated with lisinopril. Her temperature is 38.9°C (102.2°F), pulse is 105/min, respirations are 22/min, and blood pressure is 112/62 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 88%. Her leukocyte count is 10,500/mm3, and serum creatinine is 0.9 mg/dL. An X-ray of the chest shows bilateral reticulonodular opacities in the lower lobes. Serum procalcitonin level is 0.06 µg/L (N < 0.06 µg/L). What mechanism of action is the appropriate next step to manage her condition?", "answer": "Inhibition of neuraminidase", "options": {"A": "Inhibition of DNA polymerase", "B": "Inhibition of neuraminidase", "C": "Inhibition of nucleoside reverse transcriptase", "D": "Inhibition of protease", "E": "Inhibition of proton translocation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 36-year-old woman presents for a pre-employment health assessment. She has no complaints. Her last annual physical examination 8 months ago was normal. She has no significant past medical history. She is a nonsmoker and says she quit all alcohol consumption last year. A complete hepatic biochemistry panel is performed, which is significant for a serum alkaline phosphatase (ALP) level 5 times the upper limit of the normal range. Immunologic tests are positive for antimitochondrial antibodies. A liver biopsy is performed and reveals an inflammatory infiltrate surrounding the biliary ducts. Which of the following is the most likely diagnosis in this patient?", "answer": "Primary biliary cholangitis", "options": {"A": "Hepatic amyloidosis", "B": "Fascioliasis", "C": "Primary biliary cholangitis", "D": "Pancreatic cancer", "E": "Choledocolithiasis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old Caucasian man is brought to the emergency department by his roommate after he reportedly ingested a bottle of Tylenol. He reports being suddenly sad and very lonely and impulsively overdosed on some pills that he had laying around. He then immediately induced vomiting and regurgitated most of the pills back up and rushed to his roommate for help. The patient has a past medical history significant for hypertension and diabetes. He takes chlorthalidone, methadone, and glimepiride regularly. He lives in a room alone with no family and mostly keeps to himself. The patient’s vital signs are normal. Physical examination is unremarkable. The patient says that he still enjoys his life and regrets trying to overdose on the pills. He says that he will probably be fine for the next few days but has another bottle of pills he can take if he starts to feel sad again. Which of the following is the best predictor of this patient attempting to commit suicide again in the future?", "answer": "He has a previous attempt", "options": {"A": "He has a previous attempt", "B": "He has a plan", "C": "His age", "D": "His race", "E": "His lack of social support"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old man is brought to the physician by his wife for a psychiatric evaluation. Over the past 12 months, his behavior has become increasingly disruptive. His wife no longer brings him along shopping because he has attempted to grope a female cashier on 2 occasions. He has begun to address the mail carrier using a racial epithet. Three years later, the patient dies. Light microscopy of sections of the frontal and temporal lobes shows intracellular inclusions of transactive response DNA binding protein (TDP-43). These proteins are bound to a regulatory molecule that usually marks them for degradation. The regulatory molecule in question is most likely which of the following?", "answer": "Ubiquitin", "options": {"A": "Kinesin", "B": "Cyclin", "C": "Ubiquitin", "D": "Chaperone", "E": "Clathrin\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 73-year-old man presents to your office accompanied by his wife. He has been experiencing a tremor in his right hand for the last several months that seems to be worsening. He does not have any other complaints and says he’s “fine.” His wife thinks that he has also had more difficulty walking. His history is significant for hypertension and an ischemic stroke of the right middle cerebral artery 2 years ago. His medications include hydrochlorothiazide and daily aspirin. On physical exam you note that the patient speaks with a soft voice and has decreased facial expressions. He has a resting tremor that is worse on the right side. He has increased resistance to passive movement when you flex and extend his relaxed wrist. He has 5/5 strength bilaterally. Neuronal degeneration in which of the following locations is most likely responsible for the progression of this disease?", "answer": "Substantia nigra pars compacta", "options": {"A": "Substantia nigra pars compacta", "B": "Frontotemporal lobe", "C": "Subthalamic nucleus", "D": "Caudate and putamen", "E": "Vermis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman, gravida 3, para 3 comes to the physician because of a 14-month history of prolonged and heavy menstrual bleeding. Menses occur at regular 28-day intervals and last 7 days with heavy flow. She also feels fatigued. She is sexually active with her husband and does not use contraception. Vital signs are within normal limits. Pelvic examination shows a firm, irregularly-shaped uterus consistent in size with a 16-week gestation. Her hemoglobin concentration is 9 g/dL, hematocrit is 30%, and mean corpuscular volume is 92 μm3. Pelvic ultrasound shows multiple intramural masses in an irregularly enlarged uterus. The ovaries appear normal bilaterally. The patient has completed childbearing and would like definitive treatment for her symptoms. Operative treatment is scheduled. Which of the following is the most appropriate next step in management?", "answer": "Leuprolide", "options": {"A": "Progestin-only contraceptive pills", "B": "Leuprolide", "C": "Levonorgestrel-releasing intrauterine device", "D": "Tranexamic acid", "E": "Estrogen-progestin contraceptive pills"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 53-year-old man presents with swelling of the right knee. He says that the pain began the previous night and was reduced by ibuprofen and an ice-pack. The pain persists but is tolerable. He denies any recent fever, chills, or joint pains in the past. Past medical history includes a coronary artery bypass graft (CABG) a year ago for which he takes aspirin, atorvastatin, captopril, and carvedilol. The patient reports a 20-pack-year history of smoking but quits 5 years ago. He also says he was a heavy drinker for the past 30 years but now drinks only a few drinks on the weekends. On physical examination, the right knee is erythematous, warm, swollen, and mildly tender to palpation. Cardiac exam is significant for a mild systolic ejection murmur. The remainder of the examination is unremarkable. Arthrocentesis of the right knee joint is performed, which reveals the presence of urate crystals. Which of the following medications is most likely responsible for this patient's symptoms?", "answer": "Aspirin", "options": {"A": "Aspirin", "B": "Vitamin C", "C": "Carvedilol", "D": "Atorvastatin", "E": "Captopril"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 26-year-old woman presents with blood in her urine for the past 2 days. She says she has had increasing urinary frequency at night for the past several days and recently noticed a reddish tinge in her urine. She is also concerned that her feet are beginning to swell, and she has been feeling increasingly fatigued for the past week. She gives no history of joint pains, rashes, or skin changes. Past medical history is relevant for an occasional bluish discoloration of her fingers during exposure to cold. Her vital signs are a pulse of 80/min, a respiratory rate of 14/min, and blood pressure of 140/88 mm Hg. On physical examination, the patient has 1+ pitting edema of her feet bilaterally. Remainder of examination is unremarkable. Laboratory findings are significant for the following:\nSerum glucose (fasting) 88 mg/dL\nSodium 143 mEq/L\nPotassium 3.7 mEq/L\nChloride 102 mEq/L\nSerum creatinine 1.7 mg/dL\nBlood urea nitrogen 32 mg/dL\nCholesterol, total 180 mg/dL\nHDL-cholesterol 43 mg/dL\nLDL-cholesterol 75 mg/dL\nTriglycerides 135 mg/dL\nHemoglobin (Hb%) 12.5 g/dL\nMean corpuscular volume (MCV) 80 fL\nReticulocyte count 1%\nErythrocyte count 5.1 million/mm3\nThyroid stimulating hormone 4.5 μU/mL\nUrinalysis:\nGlucose negative\nProtein +++\nKetones negative\nNitrites negative\nRBCs negative\nCasts +++\nA renal biopsy is performed which reveals findings consistent with lupus nephritis. Which of the following is the next best step in treatment of this patient?", "answer": "Corticosteroids", "options": {"A": "Corticosteroids", "B": "Azathioprine", "C": "Cyclosporine", "D": "Mycophenolic acid", "E": "Cyclophosphamide"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A physician scientist is looking for a more efficient way to treat HIV. Patients infected with HIV mount a humoral immune response by producing antibodies against the HIV envelope proteins. These antibodies are the same antibodies detected by the ELISA and western blot assays used to diagnose the disease. The physician scientist is trying to generate a new, more potent antibody against the same HIV envelope proteins targeted by the natural humoral immune response. Of the following proteins, which is the most likely target of the antibody he is designing?", "answer": "gp120", "options": {"A": "gp120", "B": "CXCR4", "C": "p24", "D": "p17", "E": "CCR5"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 21-year-old man is brought to the emergency department for the evaluation of an episode of unconsciousness that suddenly happened while playing football 30 minutes ago. He was not shaking and regained consciousness after about 30 seconds. Over the past three months, the patient has had several episodes of shortness of breath while exercising as well as sensations of a racing heart. He does not smoke or drink alcohol. He takes no medications. His vital signs are within normal limits. On mental status examination, he is oriented to person, place, and time. Cardiac examination shows a systolic ejection murmur that increases with valsalva maneuver and standing and an S4 gallop. The remainder of the examination shows no abnormalities. An ECG shows a deep S wave in lead V1 and tall R waves in leads V5 and V6. Echocardiography is most likely to show which of the following findings?", "answer": "Abnormal movement of the mitral valve", "options": {"A": "Abnormal movement of the mitral valve", "B": "Symmetric left ventricular wall thickening", "C": "Ventricular septum defect", "D": "Mitral valve leaflet thickening ≥ 5 mm", "E": "Reduced left ventricular ejection fraction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 1-week-old baby is brought to the pediatrician’s office for a routine checkup. On examination, she is observed to have microcephaly with a prominent occiput. She also has clenched fists and rocker-bottom feet with prominent calcanei. A cardiac murmur is evident on auscultation. Based on the clinical findings, a diagnosis of nondisjunction of chromosome 18 is suspected. The pediatrician orders a karyotype for confirmation. He goes on to explain to the mother that her child will face severe growth difficulties. Even if her daughter progresses beyond a few months, she will not be able to reach developmental milestones at the appropriate age. In addition to the above, which of the following is most likely a consequence of this genetic disturbance?", "answer": "Death within the first year life", "options": {"A": "Alzheimer’s disease", "B": "Supravalvular aortic stenosis", "C": "Death within the first year life", "D": "Cutis aplasia", "E": "Macroglossia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 42-year-old biochemist receives negative feedback from a senior associate on a recent project. He is placed on probation within the company and told that he must improve his performance on the next project to remain with the company. He is distraught and leaves his office early. When he gives an account of the episode to his wife, she says, “I'll always be proud of you no matter what because I know that you always try your best.” Later that night, he tearfully accuses her of believing that he is a failure. Which of the following psychological defense mechanisms is he demonstrating?", "answer": "Projection", "options": {"A": "Denial", "B": "Projection", "C": "Transference", "D": "Displacement", "E": "Passive aggression"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 43-year-old woman presents to the neurology clinic in significant pain. She reports a sharp, stabbing electric-like pain on the right side of her face. The pain started suddenly 2 weeks ago. The pain is so excruciating that she can no longer laugh, speak, or eat her meals as these activities cause episodes of pain. She had to miss work last week as a result. Her attacks last about 3 minutes and go away when she goes to sleep. She typically has 2–3 attacks per day now. The vital signs include: blood pressure 132/84 mm Hg, heart rate 79/min, and respiratory rate 14/min. A neurological examination shows no loss of crude touch, tactile touch, or pain sensations on the left side of the face. The pupillary light and accommodation reflexes are normal. There is no drooping of her mouth, ptosis, or anhidrosis noted. Which of the following is the most likely diagnosis?", "answer": "Trigeminal neuralgia", "options": {"A": "Bell’s palsy", "B": "Cluster headache", "C": "Trigeminal neuralgia", "D": "Trigeminal cephalgia", "E": "Basilar migraine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "During a clinical study on an island with a population of 2540 individuals, 510 are found to have fasting hyperglycemia. Analysis of medical records of deceased individuals shows that the average age of onset of fasting hyperglycemia is 45 years, and the average life expectancy is 70 years. Assuming a steady state of population on the island with no change in environmental risk factors, which of the following is the best estimate of the number of individuals who would newly develop fasting hyperglycemia over 1 year?", "answer": "20", "options": {"A": "50", "B": "10", "C": "30", "D": "40", "E": "20"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 57-year-old woman is brought to the emergency department because of crampy abdominal pain and foul-smelling, watery diarrhea. One week ago, she underwent treatment of cellulitis with clindamycin. She has developed shortness of breath and urticaria after treatment with vancomycin in the past. Her temperature is 38.4°C (101.1°F). Abdominal examination shows mild tenderness in the left lower quadrant. Her leukocyte count is 12,800/mm3. An enzyme immunoassay is positive for glutamate dehydrogenase antigen and toxins A and B. Which of the following is the mechanism of action of the most appropriate pharmacotherapy for this patient's condition?", "answer": "Inhibition of RNA polymerase sigma subunit", "options": {"A": "Inhibition of cell wall peptidoglycan formation", "B": "Blocking of protein synthesis at 50S ribosomal subunit", "C": "Inhibition of bacterial topoisomerases II and IV", "D": "Generation of toxic free radical metabolites", "E": "Inhibition of RNA polymerase sigma subunit"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old woman comes to the physician because of abdominal discomfort, anorexia, and mild fatigue. She has systemic lupus erythematosus and takes hydroxychloroquine. She does not drink alcohol or use illicit drugs. Physical examination shows no abnormalities. Laboratory studies show:\nAlanine aminotransferase 455 U/L\nAspartate aminotransferase 205 U/L\nHepatitis B surface antigen positive\nHepatitis B surface antibody negative\nHepatitis B envelope antigen positive\nHepatitis B core antigen IgG antibody positive\nWhich of the following is the most appropriate pharmacotherapy for this patient?\"", "answer": "Tenofovir", "options": {"A": "Pegylated interferon-gamma", "B": "Acyclovir", "C": "Tenofovir", "D": "Dolutegravir", "E": "Sofosbuvir\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 34-year-old man was brought into the emergency room after he was found running in the streets. Upon arrival to the emergency room, he keeps screaming, “they are eating me alive,\" and swatting his hands. He reports that there are spiders crawling all over him. His girlfriend, who arrives shortly after, claims that he has been forgetful and would forget his keys from time to time. He denies weight loss, fever, shortness of breath, abdominal pain, or urinary changes but endorses chest pain. His temperature is 98.9°F (37.2°C), blood pressure is 160/110 mmHg, pulse is 112/min, respirations are 15/min, and oxygen saturation is 98%. He becomes increasingly agitated as he believes the healthcare providers are trying to sacrifice him to the “spider gods.” What is the most likely explanation for this patient’s symptoms?", "answer": "Cocaine use", "options": {"A": "Cocaine use", "B": "Narcolepsy", "C": "Pick disease", "D": "Schizophrenia", "E": "Temporal lobe epilepsy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old boy is brought to the pediatrician with fever, diarrhea and bilateral red eye for 7 days. His parents noted that he has never had an episode of diarrhea this prolonged, but several other children at daycare had been ill. His immunization history is up to date. His vitals are normal except for a temperature of 37.5°C (99°F). A physical exam is significant for mild dehydration, preauricular adenopathy, and bilateral conjunctival injection with watery discharge. What is the most likely diagnosis?\n ", "answer": "Adenovirus infection", "options": {"A": "Rotavirus infection", "B": "C. difficile colitis", "C": "Adenovirus infection", "D": "Norovirus infection", "E": "Vibrio parahaemolyticus infection"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "Three hours after the onset of labor, a 39-year-old woman, gravida 2, para 1, at 40 weeks' gestation has sudden worsening of abdominal pain and vaginal bleeding. 18 months ago her first child was delivered by a lower segment transverse cesarean section because of cephalopelvic disproportion. Her temperature is 37.5°C (99.5°F), pulse is 120/min, respirations are 20/min, and blood pressure is 90/50 mm Hg. Examination shows abdominal tenderness and the absence of uterine contractions. The cervix is 100% effaced and 10 cm dilated; the vertex is at -3 station. An hour before, the vertex was at 0 station. Cardiotocography shows fetal bradycardia, late decelerations, and decreased amplitude of uterine contractions. Which of the following is the most specific feature of this patient's condition?", "answer": "Loss of fetal station", "options": {"A": "Loss of fetal station", "B": "Hemodynamic instability", "C": "Fetal distress", "D": "Absent uterine contractions", "E": "Abdominal tenderness"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 64-year-old man with longstanding ischemic heart disease presents to the clinic with complaints of increasing exercise intolerance and easy fatigability for the past 2 weeks. He further states that he has been experiencing excessive daytime somnolence and shortness of breath with exertion. His wife adds that his shortness of breath is more in the recumbent position, and after approximately 2 hours of sleep, after which he suddenly wakes up suffocating and gasping for breath. This symptom is relieved after assuming an upright position for more than 30 minutes. The vital signs are as follows: heart rate, 126/min; respiratory rate, 16/min; temperature, 37.6°C (99.6°F); and blood pressure, 122/70 mm Hg. The physical examination reveals a S3 gallop on cardiac auscultation and positive hepatojugular reflux with distended neck veins. An electrocardiogram shows ischemic changes similar to ECG changes noted in the past. An echocardiogram reveals an ejection fraction of 33%. Which of the following best describes the respiratory pattern abnormality which occurs in this patient while sleeping?", "answer": "Increased pulmonary artery pressure", "options": {"A": "Increased pulmonary artery pressure", "B": "Decreased sympathetic activity", "C": "Decreased central hypercapnic ventilatory responsiveness", "D": "Increased partial pressure of oxygen", "E": "Shortened lung-to-brain circulation time"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman with a medical history significant for asthma, hypertension, and occasional IV drug use comes to the emergency department with fever. On physical exam, there are findings depicted in figure A, for which the patient cannot account. What test will be most helpful to establish the diagnosis?", "answer": "Echocardiography", "options": {"A": "Echocardiography", "B": "Chest X-ray", "C": "Pulmonary function tests", "D": "Electrocardiogram (EKG)", "E": "CT pulmonary angiography"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man is brought to the emergency department because of progressive weakness of his lower extremities and urinary incontinence for the past 3 weeks. Over the past 2 months, he has also had increasing back pain. Physical examination shows an unsteady gait. Muscle strength is decreased in both lower extremities. Sensation to pain, temperature, and position sense is absent in the buttocks, perineum, and lower extremities. Ankle clonus is present. An x-ray of the spine shows multiple sclerotic lesions in the thoracic and lumbar vertebrae. Further evaluation of this patient is most likely to show which of the following?", "answer": "Elevated prostate-specific antigen in the serum", "options": {"A": "Elevated prostate-specific antigen in the serum", "B": "Palpable thyroid nodule on neck examination", "C": "Bence Jones protein in the urine", "D": "Elevated carcinoembryonic antigen in the serum", "E": "Irregular, asymmetric mole on skin examination\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 75-year-old woman comes to the physician because of fatigue and decreasing exercise tolerance over the past 6 weeks. She also has intermittent episodes of dizziness. She has never smoked and does not drink alcohol. She takes a daily multivitamin. She appears pale. Physical examination shows a smooth liver that is palpable 1 cm below the costal margin. The spleen is not palpable. Laboratory studies show:\nHemoglobin 9.8 g/dL\nMCV 104 fL\nReticulocyte count 0.2 %\nFolate 21 ng/mL (N = 2–20)\nVitamin B12 789 pg/mL (N = 200–900)\nA peripheral blood smear shows anisocytosis and bone marrow aspirate shows ringed sideroblasts. This patient is most likely to develop which of the following?\"", "answer": "Acute myelocytic leukemia", "options": {"A": "Sézary syndrome", "B": "Chronic lymphocytic leukemia", "C": "Burkitt lymphoma", "D": "Acute myelocytic leukemia", "E": "Hairy cell leukemia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old woman has a follow-up visit with her physician. She was diagnosed with allergic rhinitis and bronchial asthma at 11 years of age. Her regular controller medications include daily high-dose inhaled corticosteroids and montelukast, but she still needs to use a rescue inhaler 3–4 times a week following exercise. She also becomes breathless with moderate exertion. After a thorough evaluation, the physician explains that her medication dosages need to be increased. She declines taking oral corticosteroids daily due to concerns about side effects. The physician prescribes omalizumab, which is administered subcutaneously every 3 weeks. Which of the following best explains the mechanism of action of the new medication that has been added to the controller medications?", "answer": "Prevention of binding of IgE antibodies to mast cell receptors", "options": {"A": "Inhibition of synthesis of interleukin-4 (IL-4)", "B": "Prevention of binding of IgE antibodies to mast cell receptors", "C": "Selective binding to interleukin-3 (IL-3) and inhibition of its actions", "D": "Prevention of binding of interleukin-5 (IL-5) to its receptors", "E": "Inhibition of synthesis of IgE antibodies"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old woman comes to the physician because of several days of fever, abdominal cramps, and diarrhea. She drank water from a stream 1 week ago while she was hiking in the woods. Abdominal examination shows increased bowel sounds. Stool analysis for ova and parasites shows flagellated multinucleated trophozoites. Further evaluation shows the presence of antibodies directed against the pathogen. Secretion of these antibodies most likely requires binding of which of the following?", "answer": "CD40 to CD40 ligand", "options": {"A": "CD8 to MHC I", "B": "CD40 to CD40 ligand", "C": "gp120 to CD4", "D": "CD28 to B7 protein", "E": "CD80/86 to CTLA-4"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought in to his pediatrician for a routine checkup. The parents mention that the child has been developing appropriately, although they have been noticing that the child appears to have chronic constipation. The parents report that their child does not routinely have daily bowel movements, and they have noticed that his abdomen has become more distended recently. In the past, they report that the patient was also delayed in passing meconium, but this was not further worked up. On exam, his temperature is 98.6°F (37.0°C), blood pressure is 110/68 mmHg, pulse is 74/min, and respirations are 14/min. The patient is noted to have a slightly distended abdomen that is nontender. Eventually, this patient undergoes a biopsy. Which of the following layers most likely reveals the causative pathologic finding of this disease?", "answer": "Submucosa", "options": {"A": "Lamina propria", "B": "Muscularis mucosa", "C": "Neural crest layer", "D": "Outer longitudinal layer of muscularis", "E": "Submucosa"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 60-year-old rock musician presents to the office because he has been feeling increasingly tired for the past 6 months. He has a history of intravenous drug use and alcohol abuse. He states that he feels quite tired, but he otherwise has no complaints. Physical examination is noncontributory. His laboratory values are normal other than moderately elevated liver enzymes. Which of the following additional tests should you order first?", "answer": "Hepatitis C virus RNA", "options": {"A": "Hepatitis A virus-specific IgM antibodies", "B": "Hepatitis B surface antigen", "C": "Hepatitis C virus RNA", "D": "Hepatitis D virus-specific IgG antibody", "E": "Hepatitis E virus-specific IgM antibodies"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 54-year-old male has a history of gout complicated by several prior episodes of acute gouty arthritis and 3 prior instances of nephrolithiasis secondary to uric acid stones. He has a serum uric acid level of 11 mg/dL (normal range 3-8 mg/dL), a 24 hr urine collection of 1300 mg uric acid (normal range 250-750 mg), and a serum creatinine of 0.8 mg/dL with a normal estimated glomerular filtration rate (GFR). Which of the following drugs should be avoided in this patient?", "answer": "Probenecid", "options": {"A": "Naproxen", "B": "Colchicine", "C": "Allopurinol", "D": "Indomethacin", "E": "Probenecid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old woman is brought to the emergency department by her family for not being responsive. The patient had locked herself in her room for several hours after breaking up with her boyfriend. When her family found her, they were unable to arouse her and immediately took her to the hospital. The patient has a past medical history of anorexia nervosa, which is being treated, chronic pain, and depression. She is not currently taking any medications. The patient has a family history of depression in her mother and grandmother. IV fluids are started, and the patient seems to be less somnolent. Her temperature is 101°F (38.3°C), pulse is 112/min, blood pressure is 90/60 mmHg, respirations are 18/min, and oxygen saturation is 95% on room air. On physical exam, the patient is somnolent and has dilated pupils and demonstrates clonus. She has dry skin and an ultrasound of her bladder reveals 650 mL of urine. The patient is appropriately treated with sodium bicarbonate. Which of the following is the best indicator of the extent of this patient's toxicity?", "answer": "QRS prolongation", "options": {"A": "Anion gap acidosis", "B": "Liver enzyme elevation", "C": "QRS prolongation", "D": "QT prolongation", "E": "Serum drug level"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "After hospitalization for urgent chemotherapy to treat Burkitt’s lymphoma, a 7-year-old boy developed paresthesias of the fingers, toes, and face. Vital signs are taken. When inflating the blood pressure cuff, the patient reports numbness and tingling of the fingers. His blood pressure is 100/65 mm Hg. Respirations are 28/min, pulse is 100/min, and temperature is 36.2℃ (97.2℉). He has excreted 20 mL of urine in the last 6 hours.\nLaboratory studies show the following:\nHemoglobin 15 g/dL\nLeukocyte count 6000/mm3 with a normal differential serum\nK+ 6.5 mEq/L\nCa+ 6.6 mg/dL\nPhosphorus 5.4 mg/dL\nHCO3− 15 mEq/L\nUric acid 12 mg/dL\nUrea nitrogen 54 mg/dL\nCreatinine 3.4 mg/dL\nArterial blood gas analysis on room air:\npH 7.30\nPCO2 30 mm Hg\nO2 saturation 95%\nWhich of the following is the most likely cause of this patient’s renal condition?", "answer": "Precipitation of uric acid in renal tubules/tumor lysis syndrome", "options": {"A": "Deposition of calcium phosphate in the kidney", "B": "Direct tubular toxicity through filtered light chains", "C": "Intense renal vasoconstriction and volume depletion", "D": "Pigment-induced nephropathy", "E": "Precipitation of uric acid in renal tubules/tumor lysis syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 16-year-old female presents to your clinic concerned that she has not had her menstrual cycle in 5 months. She has not been sexually active and her urine pregnancy test is negative. She states that she has been extremely stressed as she is in the middle of her gymnastics season and trying to get recruited for a college scholarship. Physical exam is remarkable for a BMI of 16, dorsal hand calluses, and fine hair over her cheeks. What other finding is likely in this patient?", "answer": "Low bone density", "options": {"A": "Polycythemia", "B": "Elevated TSH", "C": "Normal menstrual cycles", "D": "Elevated estrogen levels", "E": "Low bone density"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 43-year-old male with a history of thyroid cancer status post total thyroidectomy presents to his primary care physician after repeated bouts of headaches. His headaches are preceded by periods of anxiety, palpitations, and sweating. The patient says he is unable to pinpoint any precipitating factors and instead says the events occur without warning. Of note, the patient's father and uncle also have a history of thyroid cancer. On exam his vitals are: T 36.8 HR 87, BP 135/93, RR 14, and O2 Sat 100% on room air. The patient's TSH is within normal limits, and he reports taking his levothyroxine as prescribed. What is the next best step in diagnosing this patient's chief complaint?", "answer": "Plasma fractionated metanephrines", "options": {"A": "Abdominal CT scan with and without IV contrast", "B": "24-hour urine free cortisol", "C": "High dose dexamethasone suppression test", "D": "Plasma fractionated metanephrines", "E": "Plasma aldosterone/renin ratio"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old woman presents to her college campus clinic with the complaint of being unable to get up for her morning classes. She says that, because of this, her grades are being affected. For the past 6 weeks, she says she has been feeling depressed because her boyfriend dumped her. She finds herself very sleepy, sleeping in most mornings, eating more snacks and fast foods, and feeling drained of energy. She is comforted by her friend’s efforts to cheer her up but still feels guarded around any other boy that shows interest in her. The patient says she had similar symptoms 7 years ago for which she was prescribed several selective serotonin reuptake inhibitors (SSRIs) and a tricyclic antidepressant (TCA). However, none of the medications provided any long-term relief. She has prescribed a trial of Phenelzine to treat her symptoms. Past medical history is significant for a long-standing seizure disorder well managed with phenytoin. Which of the following statements would most likely be relevant to this patient’s new medication?", "answer": "“While taking this medication, you should avoid drinking red wine.”", "options": {"A": "“While taking this medication, you should avoid drinking red wine.”", "B": "“You will have a risk for cardiotoxicity from this medication.”", "C": "“While on this medication, you may have a decreased seizure threshold.”", "D": "“This medication is known to cause anorgasmia during treatment.”", "E": "“A common side effect of this medication is sedation.”"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 9-year-old boy is brought to the physician for evaluation of 2 months of progressive clumsiness, falls, and increased urinary frequency. Physical examination shows bilateral temporal visual field loss. An MRI of the head shows a small calcified suprasellar mass. The patient undergoes surgery with complete removal of the mass. Pathological examination of the specimen shows a lobular tumor composed of cysts filled with oily, brownish-yellow fluid. This mass is most likely derived from which of the following structures?", "answer": "Rathke pouch", "options": {"A": "Rathke pouch", "B": "Arachnoid cells", "C": "Astroglial cells", "D": "Lactotroph cells", "E": "Ventricular ependyma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old male is brought to the emergency department with a 1-week history of worsening headache. Over the past 2 days, he has become increasingly confused and developed nausea as well as vomiting. One week ago, he struck his head while exiting a car, but did not lose consciousness. His maternal uncle had a bleeding disorder. He appears in moderate distress. He is oriented to person and time but not to place. His temperature is 37.1°C (98.8°F), pulse is 72/min, respirations are 20/min, and blood pressure is 128/78 mm Hg. Cardiopulmonary examination is unremarkable. His abdomen is soft and nontender. Muscle strength is 5/5 in left upper and left lower extremities, and 3/5 in right upper and right lower extremities. Laboratory studies show:\nLeukocyte Count 10,000/mm3\nHemoglobin 13.6 g/dL\nHematocrit 41%\nPlatelet Count 150,000/mm3\nPT 13 seconds\naPTT 60 seconds\nSerum\nSodium 140 mEq/L\nPotassium 4.2 mEq/L\nChloride 101 mEq/L\nBicarbonate 24 mEq/L\nUrea Nitrogen 15 mg/dL\nCreatinine 1.0 mg/dL\nCT scan of the head is shown. Which of the following is the most likely cause of this patient's symptoms?\"", "answer": "Subdural hematoma", "options": {"A": "Subgaleal hemorrhage", "B": "Cerebral sinus venous thrombosis", "C": "Epidural hematoma", "D": "Subdural hematoma", "E": "Intracerebral hemorrhage"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 63-year-old woman is brought to the clinic by her husband with complaints of cognitive decline. The patient’s husband says that she has had intermittent problems with her memory for the past few years. He says she has occasional ‘bad days’ where her memory deteriorates to the point where she cannot perform activities of daily living. She is also sometimes found conversing in an empty room and, when inquired, she confirms that she is talking to a friend. There have also been had some recent falls. There is no history of fever, recent head trauma, loss of consciousness, or illicit drug use. Past medical history is significant for bronchial asthma and osteoarthritis, both managed medically. Her mother died due to metastatic breast cancer at age 71 and her father was diagnosed with Alzheimer’s disease at age 65. The patient is afebrile and her vital signs are within normal limits. Physical examination reveals a tremor present in both her hands that attenuates with voluntary movement. Deep tendon reflexes are 2+ bilaterally. Romberg’s sign is negative. She has a slow gait with a mild stooped posture. Her laboratory findings are significant for the following:\nHemoglobin 12.9 g/dL\nWhite cell count  8,520/mm³\nPlatelets 295,000/mm³\nSerum creatinine  10 mg/dL\nGlucose 94 mg/dL\nSodium 141 mEq/L\nPotassium 3.9 mEq/L\nCalcium 92 mg/dL\nFerritin 125 ng/mL\nSerum B12 305 ng/L\nTSH 2.1 µU/mL\nCeruloplasmin 45 mg/dL\nWhich of the following is the most appropriate management for this patient?", "answer": "Rivastigmine", "options": {"A": "Escitalopram", "B": "Haloperidol", "C": "Penicillamine", "D": "Rivastigmine", "E": "Ropinirole"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old woman presents for prenatal counseling at 18 weeks gestation. The patient tells you that her sister recently had a child with Down's syndrome, and the patient would like prenatal screening for Down's in her current pregnancy.\n\nWhich of the following prenatal screening tests and results would raise concern for Down's syndrome?", "answer": "Decreased AFP, increased HCG, decreased unconjugated estriol", "options": {"A": "Increased AFP, normal HCG, normal unconjugated estriol", "B": "Decreased AFP, increased HCG, decreased unconjugated estriol", "C": "Decreased AFP, decreased HCG, decreased unconjugated estriol", "D": "Normal AFP, increased HCG, decreased unconjugated estriol", "E": "Normal AFP, decreased HCG, decreased unconjugated estriol"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 28-year-old woman gives birth to a 2.2 kg child while on vacation. The mother's medical records are faxed to the hospital and demonstrate the following on hepatitis panel: hepatitis B surface antigen (HbsAg) positive, anti-hepatitis B core antigen (anti-HbcAg) positive, hepatitis C RNA is detected, hepatitis C antibody is reactive. Which of the following should be administered to the patient's newborn child?", "answer": "Hepatitis B IVIG and vaccine", "options": {"A": "Hepatitis B vaccine, ledipisvir/sofosbuvir", "B": "Hepatitis B IVIG now, hepatitis B vaccine in one month", "C": "Hepatitis B IVIG, hepatitis B vaccine and ledipisvir/sofosbuvir", "D": "Hepatitis B IVIG and vaccine", "E": "Hepatitis B vaccine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 19-year-old woman presents to the emergency department with chronic diarrhea, fatigue, and weakness. She also had mild lower extremity edema. On examination, she was noted to be pale. Blood testing revealed peripheral eosinophilia (60%) and a Hb concentration of 8 g/dL. The stool examination revealed Fasciolopsis buski eggs. Which of the following drugs would most likely be effective?", "answer": "Praziquantel", "options": {"A": "Bethional", "B": "Praziquantel", "C": "Albendazole", "D": "Niclosamide", "E": "Oxamniquine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator studying influenza virus variability isolates several distinct influenza virus strains from the respiratory secretions of a study subject. Mass spectrometry analysis of one strain shows that it expresses neuraminidase on its surface. Subsequent sequencing of this strain shows that its genome lacks the neuraminidase gene. Which of the following is the most likely explanation for this finding?", "answer": "Phenotypic mixing", "options": {"A": "Transduction", "B": "Reassortment", "C": "Recombination", "D": "Phenotypic mixing", "E": "Complementation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old male presents with left hip pain. Examination reveals mild effusions in both knees, with crepitus in both patellofemoral joints. He states his hearing has worsened recently and that he feels like his hats don't fit anymore. Bone scan reveals diffuse uptake in the calvarium, right proximal femur, and left ilium. Which of the following laboratory abnormalities would be expected in this patient?", "answer": "Increased serum alkaline phosphatase", "options": {"A": "Decreased serum alkaline phosphatase", "B": "Increased serum alkaline phosphatase", "C": "Decreased serum parathyroid hormone", "D": "Increased serum parathyroid hormone", "E": "Increased serum calcium"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 21-year-old G2P1 woman presents to the clinic and is curious about contraception immediately after her baby is born. She is anxious about taking care of one child and does not believe that she can handle the responsibility of caring for another. She has no other questions or complaints today. Her past medical history consists of generalized anxiety disorder, antithrombin deficiency, and chronic deep vein thrombosis. She has been hospitalized for acute on chronic deep vein thrombosis. Her only medication is buspirone. Her blood pressure is 119/78 mm Hg and the heart rate is 78/min. BMI of the patient is 32 kg/m2. On physical examination, her fundal height is 21 cm from pubic symphysis. No ovarian masses are palpated during the bimanual examination. Ultrasound exhibits a monoamniotic, monochorionic fetus. Which of the following forms of contraception would be the most detrimental given her risk factors?", "answer": "Transdermal contraceptive patch", "options": {"A": "Norethindrone", "B": "Copper IUD", "C": "Depot medroxyprogesterone acetate", "D": "Levonorgestrel IUD", "E": "Transdermal contraceptive patch"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 1-year-old girl born to a 40-year-old woman is undergoing an examination by a pediatric resident in the hospital. The pregnancy was uneventful and there were no complications during the delivery. The physical examination reveals midface hypoplasia with a flat nasal bridge and upslanting palpebral fissures. She has a small mouth and chest auscultation reveals a blowing holosystolic murmur that is heard best along the sternal border. The family history is unremarkable. A karyotype analysis is ordered because the resident suspects a numerical chromosomal disorder. Which of the following phenomena leads to the infant’s condition?", "answer": "Meiotic non-disjunction", "options": {"A": "Trinucleotide repeat", "B": "Meiotic non-disjunction", "C": "Uniparental disomy", "D": "Genomic imprinting", "E": "Partial deletion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man presents to the clinic with a midline swelling in his neck. He is unsure about when it appeared. He denies any difficulty with swallowing or hoarseness. His past medical history is insignificant. On physical examination, there is a 1 cm x 2 cm firm mildly tender nodule on the anterior midline aspect of the neck which moves with deglutition and elevates with protrusion of the tongue. Which of the following is the most likely embryologic origin of the nodule in this patient?", "answer": "Midline endoderm of the pharynx", "options": {"A": "The branchial cleft", "B": "1st and 2nd pharyngeal arch", "C": "4th pharyngeal arch", "D": "4th pharyngeal pouch", "E": "Midline endoderm of the pharynx"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 13-year-old girl presents after losing consciousness during class 30 minutes ago. According to her friends, she was doing okay since morning, and nobody noticed anything abnormal. The patient’s mother says that her daughter does not have any medical conditions. She also says that the patient has always been healthy but has recently lost weight even though she was eating as usual. Her vital signs are a blood pressure of 100/78 mm Hg, a pulse of 89/min, and a temperature of 37.2°C (99.0°F). Her breathing is rapid but shallow. Fingerstick glucose is 300 mg/dL. Blood is drawn for additional lab tests, and she is started on intravenous insulin and normal saline. Which of the following HLA subtypes is associated with this patient’s most likely diagnosis?", "answer": "DR3", "options": {"A": "A3", "B": "B8", "C": "DR3", "D": "B27", "E": "DR5"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old woman comes to the physician because of a 3-month history of recurring chest discomfort. The symptoms occur when walking up the stairs to her apartment or when walking quickly for 5 minutes on level terrain. She has not had shortness of breath, palpitations, or dizziness. She has hypertension and hyperlipidemia. Current medications include estrogen replacement therapy, metoprolol, amlodipine, lisinopril, hydrochlorothiazide, and rosuvastatin. She drinks 3–4 cups of coffee per day. She does not drink alcohol. Her pulse is 65/min, respirations are 21/min, and blood pressure is 145/90 mm Hg. Physical examination shows no abnormalities. A resting ECG shows normal sinus rhythm. She is scheduled for a cardiac exercise stress test in 2 days. Discontinuation of which of the following is the most appropriate next step in management at this time?", "answer": "Metoprolol and amlodipine", "options": {"A": "Metoprolol and amlodipine", "B": "Metoprolol and rosuvastatin", "C": "Estrogen and hydrochlorothiazide", "D": "Estrogen and amlodipine", "E": "Lisinopril and hydrochlorothiazide"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 13-year-old boy presents with several light brown macules measuring 4–5 cm located on his trunk. He has no other medical conditions, but his mother has similar skin findings. He takes no medications, and his vital signs are within normal limits. Ophthalmic examination findings are shown in the image below. What is the most likely neoplasm that can develop in this child?", "answer": "Neurofibroma", "options": {"A": "Acoustic neuroma", "B": "Meningioma", "C": "Dermatofibroma", "D": "Neurofibroma", "E": "Retinoblastoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman is brought to the emergency room by her mother after she is found to have cut both of her wrists with razor blades. The patient admits to a history of self-mutilation and attributed this incident to a recent breakup with a man she had been seeing for the previous 2 weeks. On morning rounds, the patient reports that the nurses are incompetent but the doctors are some of the best in the world. The patient's vitals are stable and her wrist lacerations are very superficial requiring only simple dressings without sutures. The patient is discharged a few days later and she feels well. Which of the following is the most appropriate initial treatment for this patient?", "answer": "Dialectical behavior therapy", "options": {"A": "Amitriptyline", "B": "Cognitive behavioral therapy", "C": "Dialectical behavior therapy", "D": "Fluoxetine", "E": "Lithium"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 16-year-old boy is brought to the emergency department by ambulance with a visible deformity of the upper thigh after being involved in a motor vehicle collision. He is informed that he will require surgery and is asked about his medical history. He mentions that he had surgery to remove his tonsils several years ago and at that time suffered a complication during the surgery. Specifically, shortly after the surgery began, he began to experience severe muscle contractions and an increased body temperature. Based on this information, a different class of muscle relaxants are chosen for use during the upcoming surgery. If these agents needed to be reversed, the reversal agent should be administered with which of the following to prevent off-target effects?", "answer": "Atropine", "options": {"A": "Atropine", "B": "Echothiophate", "C": "Epinephrine", "D": "Methacholine", "E": "Phentolamine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 47-year-old male presents to his primary care physician complaining of upper abdominal pain. He reports a four-month history of gnawing epigastric discomfort that improves with meals. He has lost 10 pounds over that same period. His past medical history is significant for a prolactinoma for which he underwent transphenoidal resection. He does not smoke or drink alcohol. His family history is notable for a paternal uncle and paternal grandmother with parathyroid neoplasms. His temperature is 99°F (37.2°C), blood pressure is 115/80 mmHg, pulse is 80/min, and respirations are 18/min. Upon further diagnostic workup, which of the following sets of laboratory findings is most likely?", "answer": "Elevated fasting serum gastrin that increases with secretin administration", "options": {"A": "Normal fasting serum gastrin", "B": "Elevated fasting serum gastrin that decreases with secretin administration", "C": "Elevated fasting serum gastrin that increases with somatostatin administration", "D": "Elevated fasting serum gastrin that decreases with cholecystokinin administration", "E": "Elevated fasting serum gastrin that increases with secretin administration"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old man presents to the emergency department with a fever and weakness. He states his symptoms started yesterday and have been gradually worsening. The patient has a past medical history of obesity, diabetes, alcohol abuse, as well as a 30 pack-year smoking history. He lives in a nursing home and has presented multiple times in the past for ulcers and delirium. His temperature is 103°F (39.4°C), blood pressure is 122/88 mmHg, pulse is 129/min, respirations are 24/min, and oxygen saturation is 99% on room air. Physical exam is notable for a murmur. The patient is started on vancomycin and piperacillin-tazobactam and is admitted to the medicine floor. During his hospital stay, blood cultures grow Streptococcus bovis and his antibiotics are appropriately altered. A transesophageal echocardiograph is within normal limits. The patient’s fever decreases and his symptoms improve. Which of the following is also necessary in this patient?", "answer": "Colonoscopy", "options": {"A": "Addiction medicine referral", "B": "Colonoscopy", "C": "Repeat blood cultures for contamination concern", "D": "Replace the patient’s central line and repeat echocardiography", "E": "Social work consult for elder abuse"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old man is brought to the emergency department by the police for examination. The police have reason to believe he may have swallowed a large number of cocaine-containing capsules during an attempt to smuggle the drug across the border. They request an examination of the patient to determine if this is actually the case. The patient has no history of any serious illnesses and takes no medications. He does not smoke, drinks, or consume any drugs. He appears upset. His vital signs are within normal limits. Despite the pressure by the police, he refuses to undergo any further medical evaluation. Which of the following is the most appropriate next step in the evaluation of this patient?", "answer": "Explain the risk of internal rupture to the patient", "options": {"A": "Examine the patient without his consent", "B": "Explain the risk of internal rupture to the patient", "C": "Obtain an abdominal X-ray", "D": "Refuse to examine the patient", "E": "Request a court order from the police"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-year-old boy presents to the emergency department with his parents. The boy complains of fever, neck stiffness, and drowsiness for the last several days. His past medical history is noncontributory. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. There were no sick contacts at home or at school. The family did not travel out of the area recently. His heart rate is 100/min, respiratory rate is 22/min, blood pressure is 105/65 mm Hg, and temperature is 40.5ºC (104.9°F). On physical examination, he appears unwell and confused. His heart rate is elevated with a regular rhythm and his lungs are clear to auscultation bilaterally. During the examination, he experiences a right-sided focal seizure, which is controlled with lorazepam. A head CT reveals bilateral asymmetrical hypodensities of the temporal region. A lumbar puncture is performed and reveals the following:\nWBC count 25/mm3\nCell predominance lymphocytes\nProtein elevated\nThe patient is started on a medication to treat the underlying cause of his symptoms. What is the mechanism of action of this medication?", "answer": "Inhibition of DNA polymerase", "options": {"A": "Fusion inhibition", "B": "Binding with ergosterol in the cell membrane", "C": "Inhibition of DNA polymerase", "D": "Nucleoside reverse transcriptase inhibition", "E": "Cell wall synthesis inhibition"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old man is seen by his endocrinologist for routine followup of his type 2 diabetes. Although he has previously been on a number of medication regimens, his A1C has remained significantly elevated. In order to try to better control his glucose level, the endocrinologist prescribes a new medication. He explains that this new medication works by blocking the ability of his kidneys to reabsorb glucose and therefore causes glucose wasting in the urine. Which of the following medications has this mechanism of action?", "answer": "Canagliflozin", "options": {"A": "Acarbose", "B": "Canagliflozin", "C": "Exenatide", "D": "Glyburide", "E": "Metformin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old African-American man comes to the physician for intermittent episodes of dark urine and mild flank pain. The patient has had 3 episodes of frank reddish discoloration of his urine within 1 month. He has chronic headaches and back pain for which he has been taking aspirin and ibuprofen daily for 1 year. The patient has sickle cell trait. He has smoked a pack of cigarettes daily for 10 years. He appears well. His temperature is 37.4°C (99.3°F). His pulse is 66/min, and his blood pressure is 150/90 mm Hg. Physical exam shows mild, bilateral flank tenderness. Laboratory analysis shows a serum creatinine concentration of 2.4 mg/dL. Urine studies are shown below.\nUrine\nBlood 3+\nProtein 2+\nRBC > 10/hpf\nWBC 3/hpf\nWhich of the following is the most likely underlying cause of this patient's hematuria?\"", "answer": "Renal papillary ischemia", "options": {"A": "Chronic hemoglobin filtration", "B": "Purulent renal inflammation", "C": "Renal reperfusion injury", "D": "Renal papillary ischemia", "E": "Direct nephrotoxic injury"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old woman comes to the physician because of painless lesions on the vulva that she first noticed 2 days ago. She does not have any urinary symptoms. She has gastroesophageal reflux disease for which she takes omeprazole. She has smoked one pack of cigarettes daily for 10 years. She is sexually active with multiple partners and uses condoms inconsistently. Examination shows clusters of several 3- to 5-mm raised lesions with a rough texture on the vulva. Application of a dilute acetic acid solution turns the lesions white. An HIV test is negative. Which of the following is the most appropriate next step in management?", "answer": "Cryotherapy", "options": {"A": "Parenteral benzathine penicillin", "B": "Cryotherapy", "C": "Topical mometasone", "D": "Radiotherapy", "E": "Oral acyclovir"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old male is brought into the emergency department complaining of chills, headaches, and malaise for several days. He also states that he experiences shortness of breath when climbing two flights of stairs in his home. He admits to occasionally using intravenous drugs during the previous year. On exam, his vital signs are temperature 39.2° C, heart rate 108/min, blood pressure 124/82 mm Hg, respiratory rate 20/min, and oxygen saturation 98% on room air. A holosystolic murmur is heard near the lower left sternal border. An echocardiogram confirms vegetations on the tricuspid valve. What is the most likely causative organism of this patient's condition?", "answer": "Staphylococcus aureus", "options": {"A": "Streptococcus bovis", "B": "Staphylococcus epidermidis", "C": "Streptococcus mutans", "D": "Staphylococcus aureus", "E": "Candida albicans"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old patient who immigrated from the Middle East to the United States 10 years ago presents to the emergency department because of excessive weakness, abdominal discomfort, and weight loss for the past 10 months. He has had type 2 diabetes mellitus for 10 years for which he takes metformin. He had an appendectomy 12 years ago in his home country, and his postoperative course was not complicated. He denies smoking and drinks alcohol socially. His blood pressure is 110/70 mm Hg, pulse is 75/min, and temperature is 37.1°C (98.7°F). On physical examination, the patient appears exhausted, and his sclerae are yellowish. A firm mass is palpated in the right upper abdominal quadrant. Abdominal ultrasonography shows liver surface nodularity, splenomegaly, and increased diameter of the portal vein. Which of the following is the most common complication of this patient condition?", "answer": "Ascites", "options": {"A": "Hepatic osteodystrophy", "B": "Hepatic encephalopathy", "C": "Hepatorenal syndrome", "D": "Hepatopulmonary syndrome", "E": "Ascites"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 9-year-old girl is brought to the physician by her father because of abnormal movements of her limbs for 4 days. She has had involuntary nonrhythmic movements of her arms and legs, and has been dropping drinking cups and toys. The symptoms are worse when she is agitated, and she rarely experiences them while sleeping. During this period, she has become increasingly irritable and inappropriately tearful. She had a sore throat 5 weeks ago. Her temperature is 37.2°C (99°F), pulse is 102/min, respirations are 20/min, and blood pressure is 104/64 mm Hg. Examination shows occasional grimacing with abrupt purposeless movements of her limbs. Muscle strength and muscle tone are decreased in all extremities. Deep tendon reflexes are 2+ bilaterally. She has a wide-based and unsteady gait. When the patient holds her arms in extension, flexion of the wrists and extension of the metacarpophalangeal joints occurs. When she grips the physician's index and middle fingers with her hands, her grip increases and decreases continuously. The remainder of the examination shows no abnormalities. Which of the following is the most likely underlying cause of these findings?", "answer": "Antibody cross-reactivity", "options": {"A": "Cerebral viral infection", "B": "Tumor in the posterior fossa", "C": "Antibody cross-reactivity", "D": "Trinucleotide repeat mutation", "E": "Autosomal recessive genetic mutation\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 70-year-old man comes to the physician because of progressive fatigue and lower back pain for the past 4 months. The back pain worsened significantly after he had a minor fall while doing yard work the previous day. For the past year, he has had a feeling of incomplete emptying of his bladder after voiding. His vital signs are within normal limits. Examination shows bilateral paravertebral muscle spasm, severe tenderness over the second lumbar vertebra, and mild tenderness over the lower thoracic vertebrae. Neurologic examination shows no abnormalities. His hemoglobin is 10.5 g/dl, alkaline phosphatase is 110 U/L, and serum calcium is 11.1 mg/dl. An x-ray of the skull is shown. Which of the following is the most appropriate next step in diagnosis?", "answer": "Serum protein electrophoresis", "options": {"A": "Bone marrow biopsy", "B": "Serum protein electrophoresis", "C": "Serum vitamin D levels", "D": "Prostate biopsy", "E": "Bone scan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old man presents to his primary care provider with complaints of 2 days of profuse diarrhea. He states that his stool started to turn watery and lighter in color beginning yesterday, and he has not noticed any fevers. His diarrhea episodes have become more frequent and white-colored over the past day. He has also noticed dry mouth symptoms and darker urine today. He is otherwise healthy but recently returned from a trip with friends to South Asia. None of his friends have reported any symptoms. On exam, his temperature is 98.6°F (37.0°C), blood pressure is 110/68 mmHg, pulse is 80/min, respirations are 14/min. The patient has normal skin turgor, but he has noticeably dry oral mucosa and chapped lips. The patient has dull abdominal aching but no tenderness to palpation. The stool is found to contain large quantities of comma-shaped organisms. Fecal occult blood testing is negative and no steatorrhea is found. The provider recommends immediate oral rehydration therapy. Which of the following is the likely mechanism of this patient’s diarrhea?", "answer": "Increased cyclic AMP", "options": {"A": "Decreased cyclic AMP", "B": "Increased cyclic AMP", "C": "Increased cyclic GMP", "D": "Inhibition of protein synthesis", "E": "Shortening of intestinal villi"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 6-year-old boy is brought to the physician for a well-child examination. His mother has noticed he frequently falls while running. He was born at term and pregnancy was uncomplicated. He has a seizure disorder treated with phenytoin. He is at the 20th percentile for height and at 30th percentile for weight. Vital signs are within normal limits. Examination shows decreased muscle strength in the lower extremities. There is a deep groove below the costal margins bilaterally. An x-ray of the lower extremities is shown. Which of the following is the most likely cause of these findings?", "answer": "Metabolic abnormality", "options": {"A": "Normal development", "B": "Proximal tibial growth plate disruption", "C": "Metabolic abnormality", "D": "Neoplastic growth", "E": "Heavy metal toxicity"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old woman presents with an 8-month history of insomnia and anxiety. She says that she has difficulty sleeping and has feelings of impending doom linked to her difficult financial situation. No significant family history and no current medications. The patient has prescribed an 8 week supply of medication. She follows up 4 weeks later saying that she has increased anxiety and needs a refill. She says that over the past month, due to increasing anxiety levels, she started taking extra doses of her medication to achieve an anxiolytic effect. Which of the following medications was most likely prescribed to this patient?", "answer": "Triazolam", "options": {"A": "Hydroxyzine", "B": "Buspirone", "C": "Propranolol", "D": "Triazolam", "E": "Thiopental"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-year-old girl comes to the physician because of a sore throat and subjective fevers for the past 2 weeks. She has been feeling lethargic and is unable to attend school. She has a history of multiple episodes of streptococcal pharyngitis treated with amoxicillin. She immigrated with her family to the United States from China 10 years ago. She appears thin. Her temperature is 37.8°C (100°F), pulse is 97/min, and blood pressure is 90/60 mm Hg. Examination shows pharyngeal erythema and enlarged tonsils with exudates and palatal petechiae. There is cervical lymphadenopathy. The spleen is palpated 2 cm below the left costal margin. Her hemoglobin concentration is 12 g/dL, leukocyte count is 14,100/mm3 with 54% lymphocytes (12% atypical lymphocytes), and platelet count is 280,000/mm3. A heterophile agglutination test is positive. The underlying cause of this patient's symptoms is most likely to increase the risk of which of the following conditions?", "answer": "Nasopharyngeal carcinoma", "options": {"A": "Pneumonia", "B": "Kaposi sarcoma", "C": "Nasopharyngeal carcinoma", "D": "Necrotizing retinitis", "E": "Glomerulonephritis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 49 year-old-male presents with a primary complaint of several recent episodes of severe headache, sudden anxiety, and a \"racing heart\". The patient originally attributed these symptoms to stress at work; however, these episodes are becoming more frequent and severe. Laboratory evaluation during such an episode reveals elevated plasma free metanephrines. Which of the following additional findings in this patient is most likely?", "answer": "Episodic hypertension", "options": {"A": "Decreased 24 hour urine vanillylmandelic acid (VMA) levels", "B": "Episodic hypertension", "C": "Anhidrosis", "D": "Diarrhea", "E": "Hypoglycemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old woman is brought to the emergency department following a motor vehicle accident. She was walking on the sidewalk when a car traveling at high speed knocked her off her feet. She did not sustain any obvious injury but has painful breathing. An X-ray of the chest is taken to exclude a rib fracture and contusion of the lungs. The X-ray is found to be normal except for a solitary calcified nodule located in the left hilar region. The physician then asks the patient if she is or was a smoker, or has any pertinent medical history to explain the nodule. Her past medical history is insignificant, including any previous lung infections. Physical examination does not reveal any significant signs indicative of a tumor. A chest CT is ordered and a solitary nodule of 0.5 cm is confirmed. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Repeat chest CT scan in 6 months", "options": {"A": "Positron emission scan", "B": "Mediastinoscopy", "C": "Sputum cytology", "D": "CT scan of abdomen", "E": "Repeat chest CT scan in 6 months"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old man with a past medical history significant for HIV and a social history of multiple sexual partners presents with new skin findings. His past surgical and family histories are noncontributory. The patient's blood pressure is 129/75 mm Hg, the pulse is 66/min, the respiratory rate is 16/min, and the temperature is 37.5°C (99.6°F). Physical examination reveals numerous painless skin-colored, flattened and papilliform lesions along the penile shaft and around the anus on physical exam. The application of 5% acetic acid solution causes the lesions to turn white. What is the etiology of these lesions?", "answer": "HPV (types 6 & 11)", "options": {"A": "Molluscum contagiosum", "B": "HPV (types 6 & 11)", "C": "Neisseria gonorrhoeae", "D": "HPV (types 16 & 18)", "E": "HSV (type 2)"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old female presents to her primary care physician with constipation and abdominal pain. She notes that the pain has been present for several days and is not related to food. She also reports increased urinary frequency without incontinence, as well as increased thirst. She takes no medications, but notes taking vitamin supplements daily. Her vital signs are: BP 130/72 mmHg, HR 82 bpm, T 97.0 degrees F, and RR 12 bpm. Lab studies reveal: Na 139, K 4.1, Cl 104, HCO3 25, Cr 0.9, and Ca 12.4. Further studies show an increased ionized calcium, decreased PTH, and increased phosphate. What is the most likely cause of this patient's symptoms?", "answer": "Vitamin overdose", "options": {"A": "Vitamin deficiency", "B": "Vitamin overdose", "C": "Primary endocrine dysfunction", "D": "Plasma cell neoplasm", "E": "Inherited disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A previously healthy 39-year-old woman comes to the physician because of a slowly enlarging, painless neck mass that she first noticed 3 months ago. During this period, she has also experienced intermittent palpitations, hair loss, and a weight loss of 4.5 kg (10 lb). There is no personal or family history of serious illness. She appears anxious and fidgety. Her temperature is 37.1°C (98.8°F), pulse is 101/min and irregular, respirations are 16/min, and blood pressure is 140/90 mm Hg. Physical examination shows a firm, nontender left anterior cervical nodule that moves with swallowing. Laboratory studies show:\nTSH 0.4 μU/mL\nT4 13.2 μg/dL\nT3 196 ng/dL\nUltrasonography confirms the presence of a 3-cm solid left thyroid nodule. A thyroid 123I radionuclide scintigraphy scan shows increased uptake in a nodule in the left lobe of the thyroid gland with suppression of the remainder of the thyroid tissue. Which of the following is the most likely underlying mechanism of this patient's condition?\"", "answer": "Gain-of-function mutations of the TSH receptor", "options": {"A": "Thyroid peroxidase autoantibody-mediated destruction of thyroid tissue", "B": "Gain-of-function mutations of the TSH receptor", "C": "Persistent TSH stimulation and heterogeneous thyroid tissue hyperplasia", "D": "Thyroglobulin antibody production", "E": "Activation of oncogenes promoting cell division"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old woman presents to the emergency room with complaints of severe headache, vomiting, neck stiffness, and chest pain that have developed over the last several hours. Her past medical history is notable for diabetes, hypertension, and dyslipidemia. Her temperature is 99.0°F (37.2°C), blood pressure is 197/124 mm Hg, pulse is 120/min, respirations are 19/min, and oxygen saturation is 98% on room air. Physical examination is significant for papilledema. Urinalysis reveals gross hematuria and proteinuria. Which of the following is the next best step in management for this patient?", "answer": "Esmolol", "options": {"A": "Esmolol", "B": "Hydralazine", "C": "Lisinopril", "D": "Nitroprusside", "E": "Propranolol"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A research team develops a new monoclonal antibody checkpoint inhibitor for advanced melanoma that has shown promise in animal studies as well as high efficacy and low toxicity in early phase human clinical trials. The research team would now like to compare this drug to existing standard of care immunotherapy for advanced melanoma. Because the novel drug has been determined to have few side effects, this trial will offer the novel drug to patients who are deemed to be at risk for toxicity with the current standard of care immunotherapy. Which of the following best describes the level of evidence that this study can offer?", "answer": "Level 2", "options": {"A": "Level 1", "B": "Level 2", "C": "Level 3", "D": "Level 4", "E": "Level 5"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old male with a homozygous CCR5 mutation is found to be immune to HIV infection. The patient’s CCR5 mutation interferes with the function of which viral protein?", "answer": "gp120", "options": {"A": "Reverse transcriptase", "B": "gp120", "C": "gp41", "D": "p24", "E": "pp17"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A cross-sectional study is investigating the association between smoking and the presence of Raynaud phenomenon in adults presenting to a primary care clinic in a major city. A standardized 3-question survey that assesses symptoms of Raynaud phenomenon was used to clinically diagnosis patients if they answered positively to all 3 questions. Sociodemographics, health-related information, and smoking history were collected by trained interviewers. Subjects were grouped by their reported tobacco use: non-smokers, less than 1 pack per day (PPD), between 1-2 PPD, and over 2 PPD. The results were adjusted for gender, age, education, and alcohol consumption. The adjusted odds ratios (OR) were as follows:\n\nNon-smoker: OR = reference\n<1 PPD: OR = 1.49 [95% confidence interval (CI), 1.24-1.79]\n1-2 PPD: OR = 1.91 [95% CI, 1.72-2.12]\n>2 PPD: OR = 2.21 [95% CI, 2.14-2.37]\n\nWhich of the following is represented in this study and suggests a potential causal relationship between smoking and Raynaud phenomenon?", "answer": "Dose-response", "options": {"A": "Blinding", "B": "Confounding", "C": "Consistency", "D": "Dose-response", "E": "Temporality"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 10-year-old boy is brought to a family physician by his mother with a history of recurrent headaches. The headaches are moderate-to-severe in intensity, unilateral, mostly affecting the left side, and pulsatile in nature. Past medical history is significant for mild intellectual disability and complex partial seizures that sometimes progress to secondary generalized seizures. He was adopted at the age of 7 days. His birth history and family history are not available. His developmental milestones were slightly delayed. There is no history of fever or head trauma. His vital signs are within normal limits. His height and weight are at the 67th and 54th percentile for his age. Physical examination reveals an area of bluish discoloration on his left eyelid and cheek. The rest of the examination is within normal limits. A computed tomography (CT) scan of his head is shown in the exhibit. Which of the following additional clinical findings is most likely to be present?", "answer": "Glaucoma", "options": {"A": "Ash leaf spots", "B": "Café-au-lait spots", "C": "Charcot-Bouchard aneurysm", "D": "Glaucoma", "E": "Iris hamartoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old man comes to the physician for a 2-month history of increased urinary frequency. Urodynamic testing shows a urinary flow rate of 11 mL/s (N>15) and a postvoid residual volume of 65 mL (N<50). Prostate-specific antigen level is 3.2 ng/mL (N<4). Treatment with a drug that also increases scalp hair regrowth is initiated. Which of the following is the most likely mechanism of action of this drug?", "answer": "Decreased conversion of testosterone to dihydrotestosterone", "options": {"A": "Decreased conversion of testosterone to dihydrotestosterone", "B": "Gonadotropin-releasing hormone receptor agonism", "C": "Decreased conversion of hydroxyprogesterone to androstenedione", "D": "Selective alpha-1A/D receptor antagonism", "E": "Decreased conversion of testosterone to estradiol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old man who suffered a motor vehicle accident 3 months ago presents to the office for a neurological evaluation. He has no significant past medical history and takes no current medications. He has a family history of coronary artery disease in his father and Alzheimer’s disease in his mother. On physical examination, his blood pressure is 110/60 mm Hg, the pulse is 85/min, the temperature is 37.0°C (98.6°F), and the respiratory rate is 20/min. Neurological examination is suggestive of a lesion in the anterior spinal artery that affects the anterior two-thirds of the spinal cord, which is later confirmed with angiography. Which of the following exam findings would have suggested this diagnosis?", "answer": "Preserved pressure sensation", "options": {"A": "Negative plantar extensor response in his lower limbs", "B": "Preserved pressure sensation", "C": "Flaccid paralysis on the right side", "D": "Loss of pain and temperature sensation above the level of the lesion", "E": "Loss of vibratory sense below the level of the lesion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old male presents with complaints of polydipsia and frequent, large-volume urination. Laboratory testing does not demonstrate any evidence of diabetes; however, a reduced urine osmolality of 120 mOsm/L is measured. Which of the following findings on a desmopressin test would be most consistent with a diagnosis of central diabetes insipidus?", "answer": "Increase in urine osmolality to 400 mOsm/L following vasopressin administration", "options": {"A": "Reduction in urine osmolality to 60 mOsm/L following vasopressin administration", "B": "Reduction in urine osmolality to 110 mOsm/L following vasopressin administration", "C": "Increase in urine osmolality to 130 mOsm/L following vasopressin administration", "D": "Increase in urine osmolality to 400 mOsm/L following vasopressin administration", "E": "No detectable change in urine osmolality following vasopressin administration"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old woman comes into the primary care office as a new patient with gradually worsening arthritis and reduced grip strength, primarily involving the base of her fingers, wrists, and ankles. She reports feeling slow after getting out of bed in the morning. After further questioning, she notes fatigue, low-grade fever, and feeling down. Her medical history is significant for a deep venous thrombosis, hypertension, preeclampsia, diabetes mellitus type I, and acute lymphoblastic leukemia as a child. She denies any smoking history, drinks a glass of wine each day, and endorses a past history of marijuana use but denies any current illicit drug use. Her vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 15/min. On physical examination, you note symmetric joint swelling of the metacarpophalangeal and wrist joints. Radiographs of the hands demonstrate corresponding moderate, symmetric joint space narrowing, erosions, and adjacent bony decalcification. Of the following options, which is the mechanism of her reaction?", "answer": "Type III–immune complex-mediated hypersensitivity reaction", "options": {"A": "Type I–anaphylactic hypersensitivity reaction", "B": "Type II–cytotoxic hypersensitivity reaction", "C": "Type III–immune complex-mediated hypersensitivity reaction", "D": "Type IV–cell-mediated (delayed) hypersensitivity reaction", "E": "Type III and IV–mixed immune complex and cell-mediated hypersensitivity reactions"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old G1P0 woman undergoes her 2nd-trimester ultrasound in a community hospital. During her prenatal care, she was found to have mild anemia, low levels of folate, and serum alpha-fetoprotein levels greater than 2 multiples of the median (MoM) on 2 separate occasions. Her 1st-trimester ultrasound was significant for the absence of the intracranial lucency, no visualization of the cisterna magna, and posterior shift of the brain stem. These 2nd-trimester ultrasound reports reveal the widening of the lumbosacral spine ossification centers and the presence of a sac in proximity to the lumbosacral defect. Which of the following statements best describes the congenital defect in the fetus?", "answer": "Failure of the caudal neuropore to close", "options": {"A": "Abnormal development of the caudal eminence", "B": "Persistence of the anterior accessory neurenteric canal (ANC)", "C": "Failure of the rostral neuropore to close", "D": "Failure of the caudal neuropore to close", "E": "Failure of mesenchymal cells to form a neural rod"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old male visits his gastroenterologist for a check-up one year following resection of a 2-cm malignant lesion in his sigmoid colon. Serum levels of which of the following can be used in this patient to test for cancer recurrence?", "answer": "Carcinoembryonic antigen", "options": {"A": "Alpha-fetoprotein", "B": "Carcinoembryonic antigen", "C": "Cancer antigen 125 (CA-125)", "D": "Gamma glutamyl transferase", "E": "CA-19-9 tumor marker"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 19-year-old man is seen by his primary care physician. The patient has a history of excessive daytime sleepiness going back several years. He has begun experiencing episodes in which his knees become weak and he drops to the floor when he laughs. He has a history of marijuana use. His family history is notable for hypertension and cardiac disease. His primary care physician refers him for a sleep study, and which confirms your suspected diagnosis.\n\nWhich of the following is the best first-line pharmacological treatment for this patient?", "answer": "Modafinil", "options": {"A": "Dextroamphetamine", "B": "Lisdexamfetamine", "C": "Methylphenidate", "D": "Zolpidem", "E": "Modafinil"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 58-year-old woman presents to her physician complaining of a headache in the occipital region for 1 week. Past medical history is significant for essential hypertension, managed with lifestyle modifications and 2 antihypertensives for the previous 6 months. Her blood pressure is 150/90 mm Hg. Neurological examination is normal. A third antihypertensive drug is added that acts as a selective α2 adrenergic receptor agonist. On follow-up, she reports that she does not have any symptoms and her blood pressure is 124/82 mm Hg. Which of the following mechanisms best explains the therapeutic effect of this new drug in this patient?", "answer": "Decreased peripheral sympathetic outflow", "options": {"A": "Negative inotropic effect on the heart", "B": "Vasodilation of peripheral veins", "C": "Vasodilation of peripheral arteries", "D": "Decreased peripheral sympathetic outflow", "E": "Vasodilation of peripheral arteries and peripheral veins"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman comes to the emergency department for the evaluation of mild retrosternal pain for the last 7 hours after several episodes of self-induced vomiting. The patient was diagnosed with bulimia nervosa 9 months ago. Her only medication is citalopram. She is 170 cm (5 ft 7 in) tall and weighs 62 kg (136.6 lb); BMI is 21.5 kg/m2. She appears pale. Her temperature is 37°C (98.6°F), pulse is 75/min, respirations are 21/min, and blood pressure is 110/75 mm Hg. The lungs are clear to auscultation. Cardiac examinations shows no murmurs, rubs, or gallops. The abdomen is soft and nontender with no organomegaly. The remainder of the physical examination shows swelling of the salivary glands, dry skin, and brittle nails. An ECG and an x-ray of the chest show no abnormalities. Contrast esophagram with gastrografin shows mild leakage of contrast from the lower esophagus into the mediastinum without contrast extravasation into the pleural and peritoneal cavities. Which of the following is the most appropriate next step in the management?", "answer": "Intravenous ampicillin and sulbactam therapy", "options": {"A": "Intravenous octreotide therapy", "B": "Intravenous labetalol therapy", "C": "Diagnostic endoscopy", "D": "Intravenous ampicillin and sulbactam therapy", "E": "CT scan with contrast\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old woman with an extensive psychiatric history is suspected of having metabolic acidosis after ingesting a large amount of aspirin in a suicide attempt. Labs are drawn and the values from the ABG are found to be: PCO2: 25, and HCO3: 15, but the pH value is smeared on the print-out and illegible. The medical student is given the task of calculating the pH using the pCO2 and HCO3 concentrations. He recalls from his first-year physiology course that the pKa of relevance for the bicarbonate buffering system is approximately 6.1. Which of the following is the correct formula the student should use, using the given values from the incomplete ABG?", "answer": "6.1 + log[15/(0.03*25)]", "options": {"A": "6.1 + log[15/(0.03*25)]", "B": "10^6.1 + 15/0.03*25", "C": "15/6.1 + log[10/(0.03*25)]", "D": "6.1 + log[0.03/15*25)", "E": "6.1 + log [25/(15*0.03)]"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 41-year-old woman presents to the emergency room with a fever. She has had intermittent fevers accompanied by malaise, weakness, and mild shortness of breath for the past 2 weeks. Her past medical history is notable for recurrent bloody diarrhea for over 3 years. She underwent a flexible sigmoidosopy several months ago which demonstrated contiguously granular and hyperemic rectal mucosa. She has a distant history of intravenous drug use but has been sober for the past 15 years. Her temperature is 100.8°F (38.2°C), blood pressure is 126/76 mmHg, pulse is 112/min, and respirations are 17/min. On exam, she appears lethargic but is able to answer questions appropriately. A new systolic II/VI murmur is heard on cardiac auscultation. Subungual hemorrhages are noted. Multiple blood cultures are drawn and results are pending. Which of the following pathogens is most strongly associated with this patient's condition?", "answer": "Streptococcus gallolyticus", "options": {"A": "Candida albicans", "B": "Pseudomonas aeruginosa", "C": "Staphylococcus epidermidis", "D": "Streptococcus gallolyticus", "E": "Streptococcus viridans"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old man presents to his family physician for evaluation of oral pain. He states that he has increasing pain in a molar on the top left of his mouth. The pain started 1 week ago and has been progressively worsening since then. His medical history is significant for hypertension and type 2 diabetes mellitus, both of which are currently controlled with lifestyle modifications. His blood pressure is 124/86 mm Hg, heart rate is 86/min, and respiratory rate is 14/min. Physical examination is notable for a yellow-black discoloration of the second molar on his left upper mouth. The decision is made to refer him to a dentist for further management of this cavity. The patient has never had any dental procedures and is nervous about what type of sedation will be used. Which of the following forms of anesthesia utilizes solely an oral or intravenous anti-anxiety medication?", "answer": "Minimal Sedation", "options": {"A": "Minimal Sedation", "B": "Epidural anesthesia", "C": "Deep sedation", "D": "Dissociation", "E": "Regional anesthesia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-month-old infant is brought to her pediatrician for a well-child visit. The infant was born to a 22-year-old mother via a spontaneous vaginal delivery at 38 weeks of gestation in her home. She moved to the United States approximately 3 weeks ago from a small village. She reports that her infant had 2 episodes of non-bloody and non-bilious vomiting. The infant's medical history includes eczema and 2 seizure episodes that resolved with benzodiazepines in the emergency department. Physical examination is notable for a musty body odor, eczema, and a fair skin complexion. Which of the following is the best next step in management?", "answer": "Dietary restriction", "options": {"A": "Abdominal radiography", "B": "Antiepileptic drug", "C": "Dermatology consult", "D": "Dietary restriction", "E": "MRI of the brain"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 33-year-old woman is brought to the physician by her husband because of persistent sadness for the past 2 months. During this period, she also has had difficulty sleeping and an increased appetite. She had similar episodes that occurred 2 years ago and 9 months ago that each lasted for 4 months. Between these episodes, she reported feeling very energetic and rested after 3 hours of sleep. She often went for long periods of time without eating. She works as a stock market trader and received a promotion 5 months ago. She regularly attends yoga classes on the weekends with her friends. On mental status examination, she has a blunted affect. She denies suicidal thoughts and illicit drug use. Which of the following is the most likely diagnosis?", "answer": "Cyclothymic disorder", "options": {"A": "Major depressive disorder with seasonal pattern", "B": "Persistent depressive disorder", "C": "Cyclothymic disorder", "D": "Bipolar disorder with rapid cycling", "E": "Major depressive disorder with atypical features\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A child presents to his pediatrician’s clinic for a routine well visit. He can bend down and stand back up without assistance and walk backward but is not able to run or walk upstairs. He can stack 2 blocks and put the blocks in a cup. He can bring over a book when asked, and he will say “mama” and “dada” to call for his parents, as well as 'book', 'milk', and 'truck'. How old is this child if he is developmentally appropriate for his age?", "answer": "15 months", "options": {"A": "9 months", "B": "12 months", "C": "15 months", "D": "18 months", "E": "24 months"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old girl is brought to the physician by her parents because she is severely underweight. She is easily fatigued and has difficulty keeping up with other children at her daycare. She has a good appetite and eats 3 full meals a day. She has 4 to 5 bowel movements daily with bulky, foul-smelling stools that float. She has had recurrent episodes of sinusitis since infancy. Her parents report that she recently started to snore during her sleep. She is at the 15th percentile for height and 3rd percentile for weight. Her vital signs are within normal limits. Examination shows pale conjunctivae. A few scattered expiratory crackles are heard in the thorax. There is abdominal distention. Which of the following is the most likely underlying cause of this patient's failure to thrive?", "answer": "Exocrine pancreatic insufficiency", "options": {"A": "Exocrine pancreatic insufficiency", "B": "Small intestine bacterial overgrowth", "C": "Impaired intestinal amino acid transport", "D": "Intestinal inflammatory reaction to gluten", "E": "T. whippelii infiltration of intestinal villi"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 72-year-old woman with a history of atrial fibrillation on warfarin, diabetes, seizure disorder and recent MRSA infection is admitted to the hospital. She subsequently begins therapy with another drug and is found to have a supratherapeutic International Normalized Ratio (INR). Which of the following drugs is likely contributing to this patient's elevated INR?", "answer": "Valproic acid", "options": {"A": "Phenobarbital", "B": "Glipizide", "C": "Rifampin", "D": "Carbamazepine", "E": "Valproic acid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old boy presents to the emergency department with abdominal pain and tenderness. The pain began approximately 2 days ago in the area just above his umbilicus and was crampy in nature. Earlier this morning, the pain moved laterally to his right lower abdomen. At that time, the pain in the right lower quadrant became severe and constant and woke him up from sleep. He decided to come to the hospital. The patient is nauseous and had a low-grade fever of 37.8°C (100.1°F). Other vitals are normal. Upon physical examination, the patient has rebound tenderness but a negative psoas sign while the remaining areas of his abdomen are non-tender. His rectal exam is normal. Laboratory tests show a white cell count of 15,000/mm3. Urinalysis and other laboratory findings were negative. What conclusion can be drawn about the nerves involved in the transmission of this patient’s pain during the physical exam?", "answer": "His pain is mainly transmitted by the right splanchnic nerve.", "options": {"A": "His pain is mainly transmitted by the right splanchnic nerve.", "B": "His pain is transmitted bilaterally by somatic afferent nerve fibers of the abdomen.", "C": "His pain is transmitted by somatic afferent nerve fibers located in the right flank.", "D": "His pain is transmitted by right somatic nerve fibers.", "E": "His pain is transmitted by the pelvic nerves."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 57-year-old man presents to the emergency department after an episode of syncope. He states that he was at home when he suddenly felt weak and experienced back pain that has been persistent. He states that he vomited forcefully several times after the episode. The patient has a past medical history of diabetes, hypertension, dyslipidemia, and depression. He smokes 1.5 packs of cigarettes per day and drinks 10 alcoholic beverages each night. His temperature is 97.5°F (36.4°C), blood pressure is 107/48 mmHg, pulse is 130/min, respirations are 19/min, and oxygen saturation is 99% on room air. A chest radiograph is within normal limits. Physical exam is notable for abdominal tenderness and a man resting in an antalgic position. Urinalysis is currently pending but reveals a concentrated urine sample. Which of the following is the most likely diagnosis?", "answer": "Abdominal aortic aneurysm", "options": {"A": "Abdominal aortic aneurysm", "B": "Aortic dissection", "C": "Boerhaave syndrome", "D": "Nephrolithiasis", "E": "Pancreatitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 84-year-old woman is brought by her caretaker to the physician because of a 2-day history of fever, severe headache, neck pain, and aversion to bright light. She appears uncomfortable. Her temperature is 38.5°C (101.3°F), pulse is 110/min, and blood pressure is 145/75 mm Hg. Physical examination shows involuntary flexion of the bilateral hips and knees with passive flexion of the neck. Cerebrospinal fluid analysis shows a leukocyte count of 1200/mm3 (76% segmented neutrophils, 24% lymphocytes), a protein concentration of 113 mg/dL, and a glucose concentration of 21 mg/dL. A CT scan of the brain shows leptomeningeal enhancement. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Ceftriaxone, vancomycin, and ampicillin", "options": {"A": "Vancomycin, gentamicin, and cephalexin", "B": "Vancomycin, metronidazole, and cefotaxime", "C": "Vancomycin and cefepime", "D": "Ampicillin and gentamicin", "E": "Ceftriaxone, vancomycin, and ampicillin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old woman with type 2 diabetes mellitus comes to the physician because she is concerned about the appearance of her toenails. Examination shows yellowish discoloration of all toenails on both feet. The edges of the toenails are lifted, and there is subungual debris. Potassium hydroxide preparation of scrapings from the nails shows multiple branching septate hyphae. Treatment with oral terbinafine is begun. Which of the following is the primary mechanism of action of this drug?", "answer": "Inhibition of squalene epoxidase", "options": {"A": "Interference with mitosis during metaphase", "B": "Prevention of lanosterol to ergosterol conversion", "C": "Inhibition of β-glucan synthesis", "D": "Inhibition of squalene epoxidase", "E": "Formation of pores in cell membrane"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old G3P2 woman presents to labor and delivery triage because she has had bleeding over the last day. She is currently 5 months into her pregnancy and has had no concerns prior to this visit. She previously had a delivery through cesarean section and has otherwise had uncomplicated pregnancies. She denies fever, pain, and discomfort. On presentation, her temperature is 99.1°F (37.3°C), blood pressure is 110/70 mmHg, pulse is 81/min, and respirations are 15/min. Physical exam reveals an alert woman with slow, painless, vaginal bleeding. Which of the following risk factors are associated with the most likely cause of this patient's symptoms?", "answer": "Multiparity", "options": {"A": "Early menarche", "B": "Multiparity", "C": "Presence of uterine fibroids", "D": "Pelvic inflammatory disease", "E": "Smoking"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old man visits his family physician for 10 months of persistent left flank pain, weight loss, and fatigue. Also, he has had hematuria a couple of times in the last month. His mother was diagnosed and treated for a pheochromocytoma when she was 36 years old, and his father died at 45 years due to myocardial infarction. His personal medical history is not relevant. He does not smoke and used to be a varsity athlete in high school and university. Physical examination shows temporal wasting, pale mucous membranes and palms, a palpable mass in the left flank, and a varicocele that does not reduce upon recumbency. His family physician sends the patient to the emergency department for an abdominal computed tomography (CT) scan, which shows a complex left renal mass and a hemangioblastoma in T10. A biopsy of the renal mass is ordered by the oncology team, which demonstrates compact cells with prominent nucleoli, eosinophilic cytoplasm within a network of a small and thin-walled vasculature. What is the most likely type of tumor in this patient?", "answer": "Clear-cell carcinoma", "options": {"A": "Collecting duct carcinoma", "B": "Papillary carcinoma", "C": "Clear-cell carcinoma", "D": "Chromophobe carcinoma", "E": "Oncocytic carcinoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man comes to the physician because of a 4-month history of fatigue, increased sweating, and a 5.4-kg (12-lb) weight loss. Over the past 3 weeks, he has had gingival bleeding when brushing his teeth. Twenty years ago, he was diagnosed with a testicular tumor and treated with radiation therapy. His temperature is 37.8°C (100°F), pulse is 70/min, respirations are 12/min, and blood pressure is 130/80 mm Hg. He takes no medications. Cardiopulmonary examination shows no abnormalities. The spleen is palpated 4 cm below the left costal margin. Laboratory studies show:\nHemoglobin 9 g/dL\nMean corpuscular volume 86 μm3\nLeukocyte count 110,000/mm3\nSegmented neutrophils 24%\nMetamyelocytes 6%\nMyelocytes 34%\nPromyelocytes 14%\nBlasts 1%\nLymphocytes 11%\nMonocytes 4%\nEosinophils 4%\nBasophils 2%\nPlatelet count 650,000/mm3\nMolecular testing confirms the diagnosis. Which of the following is the most appropriate next step in treatment?\"", "answer": "Imatinib therapy", "options": {"A": "Rituximab therapy", "B": "Low-dose aspirin therapy", "C": "Phlebotomy", "D": "Cytarabine and daunorubicin therapy", "E": "Imatinib therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 15-year-old boy presents with shortness of breath on exertion for the past 2 weeks. Although he does not have any other complaints, he is concerned about not gaining much weight despite a good appetite. His height is 188 cm (6 ft 2 in) and weight is 58 kg (124 lb). His blood pressure is 134/56 mm Hg and his pulse rate is 78/min. On cardiac auscultation, his apex beat is displaced laterally with a diastolic murmur lateral to the left sternal border. Slit-lamp examination shows an upward and outward displacement of both lenses. Synthesis of which of the following proteins is most likely defective in this patient?", "answer": "Fibrillin", "options": {"A": "Fibrillin", "B": "Laminin", "C": "Elastin", "D": "Fibronectin", "E": "Reticular fibers"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Three days after admission to the intensive care unit for septic shock and bacteremia from a urinary tract infection, a 34-year-old woman has persistent hypotension. Her blood cultures were positive for Escherichia coli, for which she has been receiving appropriate antibiotics since admission. She has no history of serious illness. She does not use illicit drugs. Current medications include norepinephrine, ceftriaxone, and acetaminophen. She appears well. Her temperature is 37.5 C (99.5 F), heart rate 96/min, and blood pressure is 85/55 mm Hg. Examination of the back shows costovertebral tenderness bilaterally. Examination of the thyroid gland shows no abnormalities. Laboratory studies show:\nHospital day 1 Hospital day 3\nLeukocyte count 18,500/mm3 10,300/mm3\nHemoglobin 14.1 mg/dL 13.4 mg/dL\nSerum\nCreatinine 1.4 mg/dL 0.9 mg/dL\nFasting glucose 95 mg/dL 100 mg/dL\nTSH 1.8 μU/mL\nT3, free 0.1 ng/dL (N: 0.3–0.7 ng/dL)\nT4, free 0.9 ng/dL (N: 0.5–1.8 ng/dL)\nRepeat blood cultures are negative. An x-ray of the chest shows no abnormalities. Which of the following is the most likely underlying mechanism of this patient's laboratory abnormalities?\"", "answer": "Sick euthyroid syndrome", "options": {"A": "Medication toxicity", "B": "Sick euthyroid syndrome", "C": "Fibrous thyroiditis", "D": "Pituitary apoplexy", "E": "Subclinical hypothyrodism"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old woman presents to her primary care physician with a complaint of fatigue, difficulty breathing upon exertion, and crampy lower abdominal pain. She also noticed that her stools are dark. She has had essential hypertension for 20 years, for which she takes bisoprolol. Her family history is positive for type 2 diabetes mellitus. On physical examination, she looks pale. Complete blood count shows the following:\nHemoglobin  10 g/L\nMean corpuscular volume (MCV)  70 fL\nMean corpuscular hemoglobin (MCH) 25 pg/cell\nMean corpuscular hemoglobin concentration (MCHC)  27 g/dL\nRed cell distribution width 16%\nPlatelet count 350,000/mm3\nSerum ferritin 9 ng/mL\nWhich of the following is the best initial step for this patient?", "answer": "Colonoscopy", "options": {"A": "Intra-anal glyceryl trinitrate", "B": "Double-contrast barium enema", "C": "Red cell transfusion", "D": "Colonoscopy", "E": "Rectal hydrocortisone"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old woman presents to the emergency department with intermittent uterine contractions. She is 39 weeks pregnant and experienced a deluge of fluid between her legs while she was grocery shopping. She now complains of painful contractions. She is transferred to the labor and delivery floor and a healthy male baby is delivered. He has a ruddy complexion and is crying audibly. Laboratory values demonstrate a hemoglobin of 22 g/dL and electrolytes that are within normal limits. Which of the following is the best description for the cause of this neonate's presentation?", "answer": "Maternal hyperglycemia during the pregnancy", "options": {"A": "Dehydration", "B": "Healthy infant", "C": "Maternal hyperglycemia during the pregnancy", "D": "Post-term infant", "E": "Renal abnormality"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old obese man comes to the emergency room because of paresthesias in his feet and a hypopigmented skin lesion on his knee that he first noticed 6 weeks ago. He has also had fever, fatigue, and malaise for the last week. He has a history of chronic autoimmune thyroiditis for which he takes levothyroxine. He immigrated from Indonesia 3 years ago to join his family in the United States. His temperature is 38.7°C (101.7°F) and blood pressure is 122/84 mm Hg. Physical exam shows a well-defined hypopigmented skin lesion approximately 3 cm in diameter over the anterior aspect of the right knee. The area has no hair growth and remains dry although he is diaphoretic. There is diminished sensation to light touch and pinprick in the skin lesion when compared to surrounding skin. There is reduced light touch sensation in the big toes bilaterally. After obtaining a skin biopsy of the lesion to confirm the diagnosis, which of the following is the most appropriate initial pharmacotherapy?", "answer": "Oral rifampicin and dapsone", "options": {"A": "Oral hydroxychloroquine", "B": "Topical fluconazole", "C": "Topical betamethasone", "D": "Intravenous amphotericin", "E": "Oral rifampicin and dapsone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 21-year-old woman comes to the physician because of hair loss on her frontal scalp over the past year. Menses have occurred at irregular 40- to 60-day intervals since menarche at the age of 17 years. She has no history of serious illness and takes no medications. She is 162 cm (5 ft 3 in) tall and weighs 73 kg (158.7 lb); BMI is 28 kg/m2. Her pulse is 75/min and blood pressure 130/76 mm Hg. Physical examination shows scattered pustules on her face and patches of velvety hyperpigmentation on her axilla and groin. Her morning serum cortisol concentration is 18 μg/dL. This patient's condition is most likely associated with increased stimulation of which of the following types of cells?", "answer": "Theca interna cells", "options": {"A": "Zona fasciculata cells", "B": "Leydig cells", "C": "Theca interna cells", "D": "Granulosa cells", "E": "Follicular thyroid cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to his physician by his mother for the evaluation of increased bruising for 3 weeks. The mother reports that the patient has also had two episodes of nose bleeding in the last week that subsided spontaneously within a few minutes. The boy was born at term and has been healthy except for an episode of gastroenteritis 5 weeks ago that resolved without treatment. The patient is at the 48th percentile for height and 43rd percentile for weight. He appears healthy and well nourished. His temperature is 36.5°C (97.7°F), pulse is 100/min, and his blood pressure is 100/65 mm Hg. There are a few scattered petechiae over the trunk and back. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12.5 g/dL\nMean corpuscular volume 88 μm3\nLeukocyte count 9,000/mm3\nPlatelet count 45,000/mm3\nRed cell distribution width 14% (N=13%–15%)\nA blood smear shows no abnormalities. Which of the following is the most appropriate next step in the management of this patient?\"", "answer": "Observation", "options": {"A": "Antiplatelet antibody testing", "B": "Romiplostim therapy", "C": "Splenectomy", "D": "Observation", "E": "Intravenous immunglobulin therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old woman comes to the emergency department complaining of abdominal pain and bloody vaginal discharge with clots. Her last menstrual period was 7 weeks ago. She does not smoke cigarettes or drink alcohol. She was admitted to the hospital for a deep vein thrombosis about 1 year ago and was treated with heparin followed by warfarin. Therapy ended after 6 months and she has been monitored by her primary care provider since. She has been sexually active with a new partner for 3 months and uses condoms inconsistently. Her father has type II diabetes and takes insulin. Her mother died of a stroke when she was 50. Her sister had 2 spontaneous first trimester abortions. Temperature is 38°C (100.4°F), blood pressure is 110/70 mm Hg, pulse is 98/min, respirations are 16/min, and BMI is 22 kg/m2 (48.5 pounds). On examination, her lower abdomen is tender to palpation. Vaginal examination reveals an open cervical os with blood pooling in the vaginal vault.\nLaboratory investigation:\nComplete blood count\nHemoglobin  9.5 g/dl\nLeucocytes  4,500/mm3\nPlatelets  90,000/mm3\nSerum haptoglobin  25 mg/dl (30-200 mg/dl)\nBleeding time  5 minutes\nAPTT  60 seconds\nPlasma fibrinogen  250 mg/dl (150-400 mg/dl)\nVDRL  positive\nHbsAg  negative\nAfter a mixing study, her APTT fails to correct. Urine pregnancy test is positive. What is the most likely diagnosis?", "answer": "Antiphospholipid antibody syndrome", "options": {"A": "Antiphospholipid antibody syndrome", "B": "Disseminated intravascular coagulation", "C": "Von Willebrand disease", "D": "Factor V leiden", "E": "Primary syphilis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 8-year-old boy is referred to your office by his school for kyphoscoliosis. His mother recently noticed a change in the way he walks but thought it was a normal part of his growth. She notes that he has always been clumsy and has frequent falls. He has a history of type 1 diabetes mellitus for which he receives insulin. He has no other health problems and has been doing well in school. On physical exam his temperature is 99°F (37.2°C), blood pressure is 110/75 mmHg, pulse is 80/min, and respirations are 19/min. Cardiopulmonary exam is unremarkable. On neurologic exam you notice nystagmus. Patellar reflex is absent and the patient has a staggering gait. The disorder most likely responsible for this patient’s presentation is due to an abnormality in which of the following?", "answer": "Frataxin", "options": {"A": "Frataxin", "B": "Fructokinase", "C": "Myophosphorylase", "D": "Fibrillin", "E": "Myotonin protein kinase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old man presents to the emergency department with painless yellowing of his skin. The patient states he is generally healthy and has no past medical history. He smokes 2 packs of cigarettes per day and was recently treated for a urinary tract infection with a single dose of ceftriaxone followed by a 7 day course of ciprofloxacin. He recently returned from a 3 day hiking trip and is an avid vegan. His only other medical history is a mild cough for the past few days. His temperature is 97.5°F (36.4°C), blood pressure is 122/82 mmHg, pulse is 85/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam reveals an abdomen which is non-tender. Mild scleral icterus and sublingual jaundice is noted. Which of the following is the most likely etiology of this patient’s symptoms?", "answer": "Gilbert syndrome", "options": {"A": "Carotenoid consumption", "B": "Ceftriaxone administration", "C": "Crigler-Najjar syndrome", "D": "Gilbert syndrome", "E": "Pancreatic cancer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 15-year-old boy is undergoing the bodily changes associated with puberty. He is concerned that he easily develops a foul skin odor, even with mild exercise. Which of the following glandular structures is the causative agent for this foul skin odor?", "answer": "Apocrine gland", "options": {"A": "Eccrine gland", "B": "Mucous gland", "C": "Apocrine gland", "D": "Sebaceous gland", "E": "Serous gland"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old man presents to the office with the complaint of pain in his left great toe. The pain started 2 days ago and has been progressively getting worse to the point that it is difficult to walk even a few steps. He adds that his left big toe is swollen and hot to the touch. He has never had similar symptoms in the past. He normally drinks 2–3 cans of beer every night but recently binge drank 3 nights ago. Physical examination is notable for an overweight gentleman (BMI of 35) in moderate pain, with an erythematous, swollen, and exquisitely tender left great toe. Laboratory results reveal a uric acid level of 9 mg/dL. A complete blood count shows:\nHemoglobin % 12 gm/dL\nHematocrit 45%\nMean corpuscular volume (MCV) 90 fL\nPlatelets 160,000/mm3\nLeukocytes 8,000/mm3\nSegmented neutrophils 65%\nLymphocytes 25%\nEosinophils 3%\nMonocytes 7%\nRBCs 5.6 million/mm3\nSynovial fluid analysis shows:\nCell count 55,000 cells/mm3 (80% neutrophils)\nCrystals negatively birefringent crystals present\nCulture pending\nGram stain no organisms seen\nWhich of the following is the mechanism of action of the drug that will most likely be used in the long-term management of this patient?", "answer": "Inhibits xanthine oxidase", "options": {"A": "Inhibits renal clearance of uric acid", "B": "Inhibits xanthine oxidase", "C": "Activates adenosine monophosphate (AMP) deaminase", "D": "Increases renal clearance of uric acid", "E": "Activates inosine monophosphate (IMP) dehydrogenase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old woman presented to an urgent care center with a complaint of a cough for more than 3 weeks that was accompanied by night sweats, weight loss, and malaise. On physical examination, the patient had slightly pale palpebral conjunctivae bilateral posterior cervical lymphadenopathy, but with no adventitious breath sounds in the lung fields bilaterally. The remainder of the physical examination was routine. The patient was started on a drug regimen that was to be taken for 6 months. On follow-up after 2 months, the ALT and AST levels were elevated. Which of the following anti-tubercular drug could have contributed to this labor result?", "answer": "Pyrazinamide", "options": {"A": "Rifampicin", "B": "Pyrazinamide", "C": "Isoniazid", "D": "Streptomycin", "E": "Ethambutol"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 9-year-old boy is referred to an orthopedic surgeon after his primary care physician noticed that he was developing scoliosis. He has been otherwise healthy. His family history includes blindness and a cancer causing extremely high blood pressure. On physical exam there are scattered nodules in his skin as well as the findings shown in the photographs. This patient's disorder most likely exhibits which of the following modes of inheritance?", "answer": "Autosomal dominant", "options": {"A": "Autosomal dominant", "B": "Autosomal recessive", "C": "Mitochondrial", "D": "X-linked dominant", "E": "X-linked recessive"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old man presents to his primary care physician complaining of frequent urination overnight. He states that for several years he has had trouble maintaining his urine stream along with the need for frequent urination, but the nighttime urination has only recently started. The patient also states that he has had 2 urinary tract infections in the last year, which he had never had previously. On exam, his temperature is 98.8°F (37.1°C), blood pressure is 124/68 mmHg, pulse is 58/min, and respirations are 13/min. On digital rectal exam, the prostate is enlarged but feels symmetric and smooth. Which of the following is a possible consequence of this condition?", "answer": "Increased serum creatinine", "options": {"A": "Increased serum AFP", "B": "Increased serum ALP", "C": "Increased serum creatinine", "D": "Increased serum hCG", "E": "Malignant transformation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 71-year-old man comes to the emergency department because of pain and swelling in his left leg that started after he cut his foot while swimming in the ocean. He has a history of alcoholic cirrhosis. His temperature is 38.3°C (101.0°F). Examination of the left foot shows a small, purulent wound with surrounding swelling and dusky redness extending to the mid-calf. There are numerous hemorrhagic blisters and the entire lower leg is exquisitely tender to light palpation. There is no crepitus. Blood cultures grow gram-negative bacilli that ferment lactose. Which of the following is the most likely causal organism?", "answer": "Vibrio vulnificus", "options": {"A": "Shigella flexneri", "B": "Pseudomonas aeruginosa", "C": "Clostridium perfringens", "D": "Streptococcus pyogenes", "E": "Vibrio vulnificus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to a respiratory specialist. The family physician referred the child because of recurrent respiratory infections over the past 2 years. Chest X-rays showed a lesion of < 2 cm that includes glands and cysts in the upper lobe of the right lung. Diseases affecting the immune system were investigated and ruled out. No family history of any pulmonary disease or congenital malformations exists. He was born at full term via a normal vaginal delivery with an APGAR score of 10. Which of the following should be highly considered for effective management of this child’s condition?", "answer": "Lobectomy", "options": {"A": "Antibiotics", "B": "Bronchoscopy", "C": "Observance", "D": "Lobectomy", "E": "Pneumonectomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old man is brought to the emergency department by his friends 30 minutes after falling down a flight of stairs. His friends report that they were at a college party, where he drank large amounts of alcohol. He is aggressive and restless. Examination shows tenderness to palpation and swelling of his right lower leg. An x-ray of the right leg shows a lower tibial shaft fracture. The physician recommends overnight observation and surgery the following morning. The patient refuses the suggested treatment and requests immediate discharge. Otherwise, he says, he will call his lawyer and sue the entire medical staff involved in his care. Which of the following is the most appropriate response by the physician?", "answer": "\"\"\"I understand that you want to go home, but I'll have to keep you here as long as you are intoxicated.\"\"\"", "options": {"A": "\"\"\"If you don't consent to treatment, I'll be forced to obtain consent from your parents.\"\"\"", "B": "\"\"\"Have you ever felt you should cut down on your drinking?\"\"\"", "C": "\"\"\"You can leave the hospital after signing a self-discharge against medical advice form.\"\"\"", "D": "\"\"\"I understand that you want to go home, but I'll have to keep you here as long as you are intoxicated.\"\"\"", "E": "\"\"\"I can't force you to stay here, but I'll have to inform your dean of this incident.\"\"\"\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old man comes to the physician because of a 2-week history of numbness in his left lower extremity. One month ago, he sustained a fracture of the neck of the left fibula during soccer practice that was treated with immobilization in a plaster cast. Physical examination of the left lower extremity is most likely to show which of the following findings?", "answer": "Impaired dorsiflexion of the foot", "options": {"A": "Impaired dorsiflexion of the foot", "B": "Loss of sensation over the medial calf", "C": "Inability to stand on tiptoes", "D": "Decreased ankle reflex", "E": "Loss of sensation on the sole of the foot"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 72-year-old man presents to his primary care physician due to worsening headache and double vision. His headache began several months ago, and he describes them as sharp and localized to the left side of the head. His double vision began one week prior to presentation. Medical history is significant for hypertension and type II diabetes mellitus, which is treated with lisinopril and metformin. He smokes a pack of cigarettes a day for the last 40 years. His temperature is 98.3°F (37°C), blood pressure is 148/84 mmHg, pulse is 60/min, and respirations are 14/min. On physical exam, a mild head turning towards the left is appreciated. Pupils are equal, round, and reactive to light, with a more pronounced esotropia on left-lateral gaze. The rest of the neurologic exam is otherwise normal. Magnetic resonance imaging (MRI) of the head and MR angiography shows a left-sided intracavernous carotid aneurysm. Which of the following nerves is most likely compressed by the aneurysm in this patient?", "answer": "Abducens", "options": {"A": "Oculomotor", "B": "Ophthalmic", "C": "Abducens", "D": "Trochlear", "E": "Optic"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old woman undergoes open reduction and internal fixation of the distal tibia 1 day after a fall. She has had rheumatoid arthritis for 12 years and diabetes mellitus for 2 years. Her medications over the past year have included metformin, prednisone, calcium supplements, and methotrexate. Prior to surgery, insulin was added to her medications, and the dose of prednisone was increased. She has had appropriate nutrition over the years with regular follow-ups with her healthcare professional. Which of the following is the most appropriate supplement to prevent wound failure in this patient?", "answer": "Vitamin A", "options": {"A": "Arginine", "B": "Glutamine", "C": "Vitamin A", "D": "Vitamin C", "E": "Zinc"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman makes an appointment with her family physician for a new-employment physical examination. She has no complaints and the physical examination is unremarkable. The family history is negative for malignancies and inherited disorders. During the visit, she provides the results of a Pap smear taken last week, which reports the presence of atypical squamous cells of undetermined significance (ASC-US), along with a test for HPV, which was negative. The previous Pap smear was normal (negative for intraepithelial lesions or malignancy). When would you recommend that she have another Pap smear?", "answer": "3 years", "options": {"A": "Immediately", "B": "6 months", "C": "3 years", "D": "5 years", "E": "1 year"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old woman gravida 2, para 1, comes to the physician for her first prenatal visit. Pregnancy and delivery of her first child were uncomplicated. She is not sure about the date of her last menstrual period. Pelvic examination shows a uterus consistent in size with a 10-week gestation. An ultrasound examination confirms the gestational age and shows one fetus with no indication of multiple gestations. During counseling on pregnancy risks and possible screening and diagnostic tests, the patient states she would like to undergo screening for Down syndrome. She would prefer immediate and secure screening with a low risk to herself and the fetus. Which of the following is the most appropriate next step in management at this time?", "answer": "Cell-free fetal DNA testing", "options": {"A": "Maternal serum α-fetoprotein, human chorionic gonadotropin, unconjugated estriol, and inhibin A", "B": "Amniocentesis", "C": "Nuchal translucency, pregnancy-associated plasma protein-A, human chorionic gonadotropin", "D": "Cell-free fetal DNA testing", "E": "Chorionic villus sampling"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old African American man presents with progressive fatigue, difficulty breathing on exertion, and lower extremity swelling for 3 months. The patient was seen at the emergency department 2 times before. The first time was because of back pain, and the second was because of fever and cough. He took medications at the emergency room, but he refused to do further tests recommended to him. He does not smoke or drink alcohol. His family history is irrelevant. His vital signs include a blood pressure of 110/80 mm Hg, temperature of 37.2°C (98.9°F), and regular radial pulse of 90/min. On physical examination, the patient looks pale, and his tongue is enlarged. Jugular veins become distended on inspiration. Pitting ankle edema is present on both sides. Bilateral basal crackles are audible on the chest auscultation. Hepatomegaly is present on abdominal palpation. Chest X-ray shows osteolytic lesions of the ribs. ECG shows low voltage waves and echocardiogram shows a speckled appearance of the myocardium with diastolic dysfunction and normal appearance of the pericardium. Which of the following best describes the mechanism of this patient’s illness?", "answer": "Deposition of an extracellular fibrillar protein that stains positive for Congo red in the myocardium", "options": {"A": "Thickening of the parietal pericardium with dystrophic calcification", "B": "Deposition of an extracellular fibrillar protein that stains positive for Congo red in the myocardium", "C": "Concentric hypertrophy of the myocytes with thickening of the interventricular septum", "D": "Calcification of the aortic valve orifice with obstruction of the left ventricular outflow tract", "E": "Diastolic cardiac dysfunction with reciprocal variation in ventricular filling with respiration"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 73-year-old woman is brought in by her daughter stating that her mom has become increasingly forgetful and has trouble remembering recent events. Her memory for remote events is remarkably intact. The patient is no longer able to cook for herself as she frequently leaves the stove on unattended. She has recently been getting lost in her neighborhood even though she has lived there for 30 years. Her mood is not depressed. Decreased activity in which of the following areas of the brain is known to be involved in the pathogenesis of Alzheimer's disease?", "answer": "Nucleus basalis", "options": {"A": "Locus ceruleus", "B": "Nucleus basalis", "C": "Raphe nucleus", "D": "Ventral tegmentum", "E": "Nucleus accumbens"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old female in her 20th week of pregnancy presents for a routine fetal ultrasound screening. An abnormality of the right fetal kidney is detected. It is determined that the right ureteropelvic junction has failed to recanalize. Which of the following findings is most likely to be seen on fetal ultrasound:", "answer": "Unilateral hydronephrosis", "options": {"A": "Bilateral renal agenesis", "B": "Unilateral hydronephrosis", "C": "Renal cysts", "D": "Pelvic kidney", "E": "Duplicated ureter"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old boy is brought to the pediatrician by his mother because she is concerned about the “spots” on his abdomen and back. The patient’s mother reports that there are several “light spots” on the patient’s trunk that have been slowly increasing in number. The lesions are not painful nor pruritic. The patient’s mother is worried because her nephew had vitiligo. The patient reports that he feels “fine,” but reports occasional headaches and increasing difficulty with seeing the board at school. In addition to the patient’s cousin having vitiligo, the patient’s paternal grandfather and uncle have bilateral deafness, and his mother has systemic lupus erythematous. On physical examination, there are multiple, discrete, 2-3 cm hypopigmented macules on the chest, abdomen, back, and posterior shoulders. Which of the following head and neck computed tomography findings is the patient most likely to develop?", "answer": "Bilateral vestibular schwannomas", "options": {"A": "Bilateral vestibular schwannomas", "B": "Cerebral atrophy", "C": "Optic nerve glioma", "D": "Subependymal hamartomas", "E": "Thyroid nodule"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the pediatrician's office by her parents with a complaint of foul-smelling discharge from one side of her nose for the past 2 weeks. There is no history of trauma to the nose and she was completely fine during her well-child visit last month. She was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and is meeting all developmental milestones. Her vital signs are within normal limits. Examination of the nose reveals a mucoid discharge oozing out from the left nostril. The girl panics when the physician tries to use a nasal speculum. Palpation over the facial bones does not reveal any tenderness. An X-ray image of the paranasal sinuses shows no abnormality. Which of the following is the most likely cause of this condition?", "answer": "Nasal foreign body", "options": {"A": "Nasal foreign body", "B": "Bilateral maxillary sinusitis", "C": "Nasal polyp", "D": "Septal hematoma", "E": "Nasal tumor"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old male presents to clinic complaining of coughing up small amounts of blood daily for the past week. He denies smoking, sick contacts, or recent travel. Chest radiographs demonstrates interstitial pneumonia with patchy alveolar infiltrates suggestive of multiple bleeding sites. Urinalysis is positive for blood and protein. A positive result is returned for anti-glomerular basement membrane antibody (anti-GBM Ab). What is the most likely diagnosis?", "answer": "Goodpasture disease", "options": {"A": "Systemic lupus erythematous (SLE)", "B": "Granulomatosis with polyangiitis (Wegner's)", "C": "Microscopic polyangiitis", "D": "Churg-Strauss syndrome", "E": "Goodpasture disease"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old man presents with severe respiratory distress. He was diagnosed with pulmonary hypertension secondary to occupational pneumoconiosis. Biopsy findings of the lung showed ferruginous bodies. What is the most likely etiology?", "answer": "Asbestos", "options": {"A": "Coal", "B": "Iron", "C": "Asbestos", "D": "Beryllium", "E": "Silica"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old G1P1 with a history of diabetes and epilepsy gives birth to a female infant at 32 weeks gestation. The mother had no prenatal care and took no prenatal vitamins. The child’s temperature is 98.6°F (37°C), blood pressure is 100/70 mmHg, pulse is 130/min, and respirations are 25/min. On physical examination in the delivery room, the child’s skin is pink throughout and he cries on stimulation. All four extremities are moving spontaneously. A tuft of hair is found overlying the infant’s lumbosacral region. Which of the following medications was this patient most likely taking during her pregnancy?", "answer": "Valproic acid", "options": {"A": "Lithium", "B": "Ethosuximide", "C": "Warfarin", "D": "Gentamicin", "E": "Valproic acid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Following a motor vehicle accident, a 63-year-old man is scheduled for surgery. The emergency physician notes a posture abnormality in the distal left lower limb and a fracture-dislocation of the right hip and acetabulum based on the radiology report. The senior orthopedic resident mistakenly notes a fraction dislocation of the left hip and marks the left hip as the site of surgery. The examination by the surgeon in the operating room shows an externally rotated and shortened left lower limb. The surgeon inserts a pin in the left tibia but erroneously operates on the left hip. A review of postoperative imaging leads to a second surgery on the fracture-dislocation of the right hip. Rather than the surgeon alone, the surgical team and the hospital system are held accountable for not implementing the mandatory protocol of preincision ‘time-out’ and compliance monitoring. Which of the following best describes this approach to prevent medical errors?", "answer": "Swiss-cheese model", "options": {"A": "Closed-loop communication", "B": "Primordial prevention", "C": "Root cause analysis", "D": "Swiss-cheese model", "E": "Sentinel event"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old woman with hypertension is brought to the emergency department 30 minutes after having a generalized, tonic-clonic seizure. She has had recurrent headaches and dizziness in the last 3 months. One year ago, she had diarrhea after a trip to Ecuador that resolved without treatment. She has not received any medical care in the last five years. She has smoked 1 pack of cigarettes daily for 20 years. Her temperature is 36°C (96.8°F) and blood pressure is 159/77mm Hg. Physical examination shows dysarthria and hyperreflexia. She is confused and oriented only to name and place. Four brain lesions are found in a CT scan of the brain; one of the lesions is shown. Which of the following is most likely to have prevented this patient's condition?", "answer": "Avoidance of contaminated food", "options": {"A": "Avoidance of contaminated food", "B": "Vaccination against meningococcus", "C": "Avoidance of cat feces", "D": "Smoking cessation", "E": "Improved blood pressure control"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought to the physician because of increasing swelling around his eyes for the past 3 days. During this period, he has had frothy light yellow urine. He had a sore throat 12 days ago. He appears tired. His temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 105/65 mm Hg. Examination shows periorbital edema and pitting edema of the lower extremities. Cardiopulmonary examination shows no abnormalities. Which of the following findings on urinalysis is most likely associated with this patient's condition?", "answer": "Fatty casts", "options": {"A": "WBC casts", "B": "Hyaline casts", "C": "RBC casts", "D": "Fatty casts", "E": "Muddy brown casts"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old female presents to the emergency room complaining of severe abdominal pain. She reports a six-month history of worsening dull mid-epigastric pain that she had attributed to stress at work. She has lost fifteen pounds over that time. She also reports that her stools have become bulky, foul-smelling, and greasy. Over the past few days, her abdominal pain acutely worsened and seemed to radiate to her back. She also developed mild pruritus and yellowing of her skin. Her temperature is 101°F (38.3°C), blood pressure is 145/85 mmHg, pulse is 110/min, and respirations are 20/min. On examination, her skin appears yellowed and she is tender to palpation in her mid-epigastrium and right upper quadrant. She is subsequently sent for imaging. If a mass is identified, what would be the most likely location of the mass?", "answer": "Ampulla of Vater", "options": {"A": "Common hepatic duct", "B": "Cystic duct", "C": "Common bile duct", "D": "Pancreatic duct", "E": "Ampulla of Vater"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 67-year-old woman comes to the physician because of intermittent chest pain and dizziness on exertion for 6 months. Her pulse is 76/min and blood pressure is 125/82 mm Hg. Cardiac examination shows a grade 3/6, late-peaking, crescendo-decrescendo murmur heard best at the right upper sternal border. An echocardiogram confirms the diagnosis. Three months later, the patient returns to the physician with worsening shortness of breath for 2 weeks. An ECG is shown. Which of the following changes is most likely responsible for this patient's acute exacerbation of symptoms?", "answer": "Decreased left ventricular preload", "options": {"A": "Impaired contractility of the left ventricle", "B": "Impaired pulmonary artery outflow", "C": "Decreased left ventricular preload", "D": "Decreased impulse conduction across the AV node", "E": "Increased systemic vascular resistance"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old woman presents with fever, pain, and swelling of the right leg. She says that her right leg swelling has gradually worsened over the last 2 weeks. She has also noted worsening fatigue and anorexia. Two days ago, she developed a low-grade fever. Her past medical history is significant for type 2 diabetes mellitus diagnosed 5 years ago and managed with metformin. Her temperature is 38.0°C (100.4°F), pulse is 110/min, blood pressure is 110/72 mm Hg, and respiratory rate is 16/min. On physical examination, there is a painful swelling of the right lower extremity extending to just below the knee joint. The overlying skin is tense, glossy, erythematous, and warm to touch. A diagnosis of cellulitis is established and appropriate antibiotics are started. Which of the following best describes the organism most likely responsible for this patient’s condition?", "answer": "Catalase-negative cocci in chain", "options": {"A": "Catalase-negative cocci in grape-like clusters", "B": "Catalase-negative cocci in chain", "C": "Shows no hemolysis on blood agar", "D": "Gram-negative cocci with beta hemolysis", "E": "Catalase-positive Gram-positive diplococci"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-year-old boy is brought to a pediatric clinic by his mother because he had difficulty swallowing for 4 days. He was diagnosed with asthma 3 months ago and has been using an inhaler as directed by the pediatrician. The child does not have a fever or a cough and is not short of breath. He denies pain during swallowing. His vital signs include: temperature 35.8℃ (96.5℉), respiratory rate 14/min, blood pressure 90/40 mm Hg, and pulse 80/min. The oral examination reveals a slightly raised white lesion over his tongue (as shown in the provided photograph) and oropharynx. What is the most likely diagnosis?", "answer": "Oral thrush", "options": {"A": "Lichen planus", "B": "Leukoplakia", "C": "Primary gingivostomatitis", "D": "Oral thrush", "E": "Oral hairy leukoplakia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 13-year-old boy is brought to the emergency room by his mother for a generalized tonic-clonic seizure that occurred while attending a laser light show. His mother says that he has been otherwise healthy but “he often daydreams”. Over the past several months, he has reported recurrent episodes of jerky movements of his fingers and arms. These episodes usually occurred shortly after waking up in the morning. He has not lost consciousness during these episodes. Which of the following is the most appropriate treatment for this patient's condition?", "answer": "Valproate", "options": {"A": "Carbamazepine", "B": "Tiagabine", "C": "Valproate", "D": "Vigabatrin", "E": "Diazepam\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-day-old male newborn is brought to the physician because of increasing yellowish discoloration of his skin for 2 days. He was born at 38 weeks' gestation and weighed 2466 g (5 lb 7 oz); he currently weighs 2198 g (4 lb 14 oz). Pregnancy was complicated by pregnancy-induced hypertension. The mother says he breastfeeds every 3 hours and has 3 wet diapers per day. His temperature is 37°C (98.6°F), pulse is 165/min, and respirations are 53/min. Examination shows jaundice and scleral icterus. The anterior fontanelle is mildly sunken. The abdomen is soft and nontender; there is no organomegaly. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHematocrit 58%\nSerum\nBilirubin\n_ Total 20 mg/dL\n_ Conjugated 0.8 mg/dL\nWhich of the following is the most likely cause of these findings?\"", "answer": "Inadequate breastfeeding", "options": {"A": "Increased breakdown of fetal RBCs", "B": "Elevated β-glucuronidase in breast milk", "C": "Inadequate breastfeeding", "D": "Gram-negative infection", "E": "Defective alpha-globin chains of hemoglobin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 19-year-old man and recent immigrant from Brazil present to the clinic. He has no known past medical, past surgical, or family history. The patient admits to having several regular sexual partners. Today, he complains of a skin rash on his back. He is unclear when it started but became aware when one of his partners pointed it out. A review of systems is otherwise negative. Physical examination reveals numerous hypopigmented skin lesions over his upper back. When questioned, he states that they do not get darker after spending time in the sun. On examination, there is a 5 cm (1.9 in) patch of hypopigmented skin in the center of his back with a fine-scale overlying it. What is the most likely diagnosis?", "answer": "Tinea versicolor", "options": {"A": "Tinea versicolor", "B": "Mycosis fungoides", "C": "Pityriasis rosea", "D": "Vitiligo", "E": "Secondary syphilis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 56-year-old woman visits her family physician accompanied by her son. She has recently immigrated to Canada and does not speak English. Her son tells the physician that he is worried that his mother gets a lot of sugar in her diet and does not often monitor her glucose levels. Her previous lab work shows a HbA1c value of 8.7%. On examination, her blood pressure is 130/87 mm Hg and weight is 102 kg (224.9 lb). Which of the following is the correct location of where the glucose transport is most likely affected in this patient?", "answer": "Skeletal muscle", "options": {"A": "Pancreas", "B": "Liver", "C": "Brain", "D": "Skeletal muscle", "E": "Red blood cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old woman comes to the emergency department because of severe right flank pain for 2 hours. The pain is colicky in nature and she describes it as 9 out of 10 in intensity. She has had 2 episodes of vomiting. She has no history of similar episodes in the past. She is 160 cm (5 ft 3 in) tall and weighs 104 kg (229 lb); BMI is 41 kg/m2. Her temperature is 37.3°C (99.1°F), pulse is 96/min, respirations are 16/min and blood pressure is 116/76 mm Hg. The abdomen is soft and there is mild tenderness to palpation in the right lower quadrant. Bowel sounds are reduced. The remainder of the examination shows no abnormalities. Her leukocyte count is 7,400/mm3. A low-dose CT scan of the abdomen and pelvis shows a round 12-mm stone in the distal right ureter. Urine dipstick is mildly positive for blood. Microscopic examination of the urine shows RBCs and no WBCs. 0.9% saline infusion is begun and intravenous ketorolac is administered. Which of the following is the most appropriate next step in management?", "answer": "Ureterorenoscopy", "options": {"A": "Ureterorenoscopy", "B": "Extracorporeal shock wave lithotripsy", "C": "Observation", "D": "Ureteral stenting", "E": "Thiazide diuretic therapy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man presents to the emergency department with shortness of breath and weakness. Past medical history includes coronary artery disease, arterial hypertension, and chronic heart failure. He reports that the symptoms started around 2 weeks ago and have been gradually worsening. His temperature is 36.5°C (97.7°F), blood pressure is 135/90 mm Hg, heart rate is 95/min, respiratory rate is 24/min, and oxygen saturation is 94% on room air. On examination, mild jugular venous distention is noted. Auscultation reveals bilateral loud crackles. Pitting edema of the lower extremities is noted symmetrically. His plasma brain natriuretic peptide level on rapid bedside assay is 500 pg/mL (reference range < 125 pg/mL). A chest X-ray shows enlarged cardiac silhouette. He is diagnosed with acute on chronic left heart failure with pulmonary edema and receives immediate care with furosemide. The physician proposes a drug trial with a new BNP stabilizing agent. Which of the following changes below are expected to happen if the patient is enrolled in this trial?", "answer": "Restricted aldosterone release", "options": {"A": "Increased water reabsorption by the renal collecting ducts", "B": "Increased blood pressure", "C": "Restricted aldosterone release", "D": "Increased potassium release from cardiomyocytes", "E": "Inhibition of funny sodium channels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 11-month-old boy presents with a scaly erythematous rash on his back for the past 2 days. No significant past medical history. Family history is significant for the fact that the patient’s parents are first-degree cousins. In addition, his older sibling had similar symptoms and was diagnosed with a rare unknown skin disorder. On physical examination, whitish granulomatous plaques are present in the oral mucosa, which exhibit a tendency to ulcerate, as well as a scaly erythematous rash on his back. A complete blood count reveals that the patient is anemic. A plain radiograph of the skull shows lytic bone lesions. Which of the following immunohistochemical markers, if positive, would confirm the diagnosis in this patient?", "answer": "CD1a", "options": {"A": "CD21", "B": "CD1a", "C": "CD40L", "D": "CD15", "E": "CD30"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old man is brought to the emergency department 10 minutes after falling down a flight of stairs. An x-ray of the right wrist shows a distal radius fracture. A rapidly acting intravenous anesthetic agent is administered, and closed reduction of the fracture is performed. Following the procedure, the patient reports palpitations and says that he experienced an “extremely vivid dream,” in which he felt disconnected from himself and his surroundings while under anesthesia. His pulse is 110/min and blood pressure is 140/90 mm Hg. The patient was most likely administered a drug that predominantly blocks the effects of which of the following neurotransmitters?", "answer": "Glutamate", "options": {"A": "Glutamate", "B": "Norepinephrine", "C": "Endorphin", "D": "Gamma-aminobutyric acid", "E": "Dopamine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An otherwise healthy 45-year-old woman comes to the physician because of a 2-week history of an itchy rash on her left nipple. The rash began as small vesicles on the nipple and spread to the areola. It has become a painful ulcer with yellow, watery discharge that is occasionally blood-tinged. She has asthma treated with theophylline and inhaled salbutamol. Her younger sister was diagnosed with endometrial cancer a year ago. Examination shows a weeping, ulcerated lesion involving the entire left nipple-areolar complex. There are no breast masses, dimpling, or axillary lymphadenopathy. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Paget disease of the breast\n\"", "options": {"A": "Inflammatory breast cancer", "B": "Mastitis", "C": "Breast abscess", "D": "Breast fibroadenoma", "E": "Paget disease of the breast\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old woman in her 18th week of pregnancy based on the last menstrual period (LMP) presents to her obstetrician for an antenatal check-up.\nThe antenatal testing is normal, except the quadruple screen results which are given below:\nMaternal serum alpha-fetoprotein (MS-AFP) low\nUnconjugated estriol low\nHuman chorionic gonadotropin (hCG) high\nInhibin-A high\nWhich of the following conditions is the most likely the cause of the abnormal quadruple screen?", "answer": "Trisomy 21", "options": {"A": "Trisomy 21", "B": "Spina bifida", "C": "Omphalocele", "D": "Gastroschisis", "E": "Fetal alcohol syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 46-year-old man presents with increasing fatigue and weakness for the past 3 months. He works as a lawyer and is handling a complicated criminal case which is very stressful, and he attributes his fatigue to his work. He lost 2.3 kg (5.0 lb) during this time despite no change in diet or activity level. His past history is significant for chronic constipation and infrequent episodes of bloody stools. Family history is significant for his father and paternal uncle who died of colon cancer. and who were both known to possess a genetic mutation for the disease. He has never had a colonoscopy or had any genetic testing performed. Physical examination is significant for conjunctival pallor. A colonoscopy is performed and reveals few adenomatous polyps. Histopathologic examination shows high-grade dysplasia and genetic testing reveals the same mutation as his father and uncle. The patient is concerned about his 20-year-old son. Which of the following is the most appropriate advice regarding this patient’s son?", "answer": "A genetic test followed by colonoscopy for the son should be ordered.", "options": {"A": "The son should undergo a prophylactic colonic resection.", "B": "An immediate colonoscopy should be ordered for the son.", "C": "The son doesn't need to be tested now.", "D": "A genetic test followed by colonoscopy for the son should be ordered.", "E": "Screening can be started by 50 years of age as the son’s risk is similar to the general population."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Background:\nBeta-blockers reduce mortality in patients who have heart failure reduced ejection fraction and are on background treatment with diuretics and angiotensin-converting enzyme inhibitors. We aimed to compare the effects of carvedilol and metoprolol on clinical outcome.\nMethods:\nIn a multicenter, double-blind, and randomized parallel group trial, we assigned 1,511 patients with chronic heart failure to treatment with carvedilol (target dose 25 mg twice daily) and 1,518 to metoprolol (metoprolol tartrate, target dose 50 mg twice daily). Patients were required to have chronic heart failure (NYHA II-IV), previous admission for a cardiovascular reason, an ejection fraction of less than 0.35, and have been treated optimally with diuretics and angiotensin-converting enzyme inhibitors unless not tolerated. The primary endpoints were all-cause mortality and the composite endpoint of all-cause mortality or all-cause admission. The analysis was done by intention to treat.\nFindings:\nThe mean study duration was 58 months (SD 6). The mean ejection fraction was 0.26 (0.07), and the mean age 62 years (11). The all-cause mortality was 34% (512 of 1,511) for carvedilol and 40% (600 of 1,518) for metoprolol (hazard ratio 0.83 [95% CI 0.74-0.93], p=0.0017). The reduction of all-cause mortality was consistent across predefined subgroups. The incidence of side effects and drug withdrawals did not differ by much between the two study groups.\nTo which of the following patients are the results of this clinical trial applicable?", "answer": "A 68-year-old male with NYHA class II systolic heart failure and EF 30%", "options": {"A": "A 62-year-old male with primarily preserved ejection fraction heart failure", "B": "A 75-year-old female with systolic dysfunction and an EF of 45%", "C": "A 56-year-old male with NYHA class I systolic heart failure", "D": "A newly diagnosed 66-year-old male who has yet to begin treatment for his NYHA class II left-sided heart failure", "E": "A 68-year-old male with NYHA class II systolic heart failure and EF 30%"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 48-year-old female comes into the ER with chest pain. An electrocardiogram (EKG) shows a heart beat of this individual in Image A. The QR segment best correlates with what part of the action potential of the ventricular myocyte shown in Image B?", "answer": "Phase 0, which is primarily characterized by sodium influx", "options": {"A": "Phase 0, which is primarily characterized by sodium influx", "B": "Phase 0, which is primarily characterized by potassium efflux", "C": "Phase 1, which is primarily characterized by potassium and chloride efflux", "D": "Phase 1, which is primarily characterized by calcium efflux", "E": "Phase 3, which is primarily characterized by potassium efflux"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Ten days after being discharged from the hospital, a 42-year-old man comes to the emergency department because of reduced urine output for 3 days. Physical examination is normal. Serum creatinine concentration is 2.9 mg/dL. Urinalysis shows brownish granular casts and 2+ proteinuria. Renal biopsy shows patchy necrosis of the proximal convoluted tubule with sloughing of tubular cells into the lumen and preservation of tubular basement membranes. Administration of which of the following drugs during this patient's hospitalization is most likely the cause of the observed decrease in renal function?", "answer": "Gentamicin", "options": {"A": "Captopril", "B": "Aspirin", "C": "Acyclovir", "D": "Omeprazole", "E": "Gentamicin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to the physician because of a 4-week history of generalized fatigue and malaise. He was born at term and has been healthy since. His mother has a history of recurrent anemia. He appears pale. His temperature is 37°C (98.6°F) and pulse is 97/min. Examination shows pale conjunctivae and jaundice. The abdomen is soft and nontender; the spleen is palpated 3–4 cm below the left costal margin. Laboratory studies show:\nHemoglobin 9.3 g/dL\nMean corpuscular volume 81.3 μm3\nMean corpuscular hemoglobin concentration 39% Hb/cell\nLeukocyte count 7300/mm3\nPlatelet count 200,000/mm3\nRed cell distribution width 19% (N = 13–15)\nWhich of the following is most likely to confirm the diagnosis?\"", "answer": "Eosin-5-maleimide binding test", "options": {"A": "Fluorescent spot test", "B": "Direct antiglobulin test", "C": "Eosin-5-maleimide binding test", "D": "Indirect antiglobulin test", "E": "Peripheral smear"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 71-year-old woman presents with high-grade fever and chills, difficulty breathing, and a productive cough with rust-colored sputum. She complains of a sharp left-sided chest pain. Physical examination reveals increased fremitus, dullness to percussion, and bronchial breath sounds on the lower left side. A chest X-ray shows left lower lobe consolidation. The offending organism that was cultured from the sputum was catalase-negative and had a positive Quellung reaction. The organism will show which gram stain results?", "answer": "Gram-positive diplococci", "options": {"A": "Cannot be seen with gram staining since the organism lacks a cell wall", "B": "Gram-negative rod", "C": "Gram-positive diplococci", "D": "Gram-negative diplococci", "E": "Gram-positive cocci in clusters"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "You are conducting a lab experiment on skeletal muscle tissue to examine force in different settings. The skeletal muscle tissue is hanging down from a hook. The experiment has 3 different phases. In the first phase, you compress the muscle tissue upwards, making it shorter. In the second phase, you attach a weight of 2.3 kg (5 lb) to its lower vertical end. In the third phase, you do not manipulate the muscle length at all. At the end of the study, you see that the tension is higher in the second phase than in the first one. What is the mechanism underlying this result?", "answer": "Lengthening of the muscle in phase 2 increases passive tension.", "options": {"A": "There are more actin-myofibril cross-bridges attached in phase 2 than in phase 1.", "B": "Shortening of the muscle in phase 1 uses up ATP stores.", "C": "Lengthening of the muscle in phase 2 increases passive tension.", "D": "The tension in phase 1 is only active, while in phase 2 it is both active and passive.", "E": "Shortening the muscle in phase 1 pulls the actin and myosin filaments apart."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 20-year-old woman reports to student health complaining of 5 days of viral symptoms including sneezing and a runny nose. She started coughing 2 days ago and is seeking cough medication. She additionally mentions that she developed a fever 2 days ago, but this has resolved. On exam, her temperature is 99.0°F (37.2°C), blood pressure is 118/76 mmHg, pulse is 86/min, and respirations are 12/min. Changes in the activity of warm-sensitive neurons in which part of her hypothalamus likely contributed to the development and resolution of her fever?", "answer": "Anterior hypothalamus", "options": {"A": "Anterior hypothalamus", "B": "Lateral area", "C": "Paraventricular nucleus", "D": "Posterior hypothalamus", "E": "Suprachiasmatic nucleus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman is brought to a counselor by her father after he found out that she is being physically abused by her husband. The father reports that she refuses to end the relationship with her husband despite the physical abuse. She says that she feels uneasy when her husband is not around. She adds, “I'm worried that if I leave him, my life will only get worse.” She has never been employed since they got married because she is convinced that nobody would hire her. Her husband takes care of most household errands and pays all of the bills. Physical examination shows several bruises on the thighs and back. Which of the following is the most likely diagnosis?", "answer": "Dependent personality disorder", "options": {"A": "Borderline personality disorder", "B": "Separation anxiety disorder", "C": "Dependent personality disorder", "D": "Schizoid personality disorder", "E": "Avoidant personality disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old patient presents to the emergency department after a motor vehicle accident. The patient was an unrestrained driver involved in a head-on collision. The patient is heavily intoxicated on what he claims is only alcohol. An initial trauma assessment is performed, and is notable for significant bruising of the right forearm. The patient is in the trauma bay, and complains of severe pain in his right forearm. A physical exam is performed and is notable for pallor, decreased sensation, and cool temperature of the skin of the right forearm. Pain is elicited upon passive movement of the right forearm and digits. A thready radial pulse is palpable. A FAST exam is performed, and is negative for signs of internal bleeding. The patient's temperature is 99.5°F (37.5°C), pulse is 100/min, blood pressure is 110/70 mmHg, respirations are 12/min, and oxygen saturation is 98% on room air. Radiography of the right forearm is ordered. The patient is still heavily intoxicated. Which of the following is the best next step in management?", "answer": "Fasciotomy", "options": {"A": "Detoxification", "B": "IV fluids", "C": "Analgesics", "D": "Fasciotomy", "E": "Pressure measurement"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 57-year-old man presents with 2 days of severe, generalized, abdominal pain that is worse after meals. He is also nauseated and reports occasional diarrhea mixed with blood. Apart from essential hypertension, his medical history is unremarkable. His vital signs include a temperature of 36.9°C (98.4°F), blood pressure of 145/92 mm Hg, and an irregularly irregular pulse of 105/min. Physical examination is only notable for mild periumbilical tenderness. Which of the following is the most likely diagnosis?", "answer": "Acute mesenteric ischemia", "options": {"A": "Acute pancreatitis", "B": "Crohn's disease", "C": "Acute mesenteric ischemia", "D": "Diverticular disease", "E": "Gastroenteritis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 66-year-old farmer is being evaluated for abnormal lung findings on a low dose chest CT scan obtained as part of his lung cancer screening. He has a 50-pack-year smoking history and has been hesitant to quit. He has a non-productive cough but brushes it away saying he is not bothered by it. He denies ever coughing up blood, breathlessness, chest pain, fatigue, or weight loss. He has never sought any medical care and states that he has always been in good shape. He consumes alcohol moderately and uses marijuana occasionally. He lives with his wife and has not traveled recently. On physical examination, his temperature is 37.1°C (98.8°F), blood pressure is 148/70 mm Hg, and pulse rate is 95/min. His BMI is 32 kg/m2. A general physical examination is unremarkable. Coarse breath sounds are present bilaterally. The cardiac exam is normal. Laboratory studies show a normal complete blood count and comprehensive metabolic panel. A follow-up high-resolution CT scan is performed that shows small irregular subcentimeter pulmonary nodules, several of which are cavitated in both lungs, predominantly distributed in the upper and middle zones. There is no mediastinal or hilar lymphadenopathy. A transbronchial needle aspiration of the lesion is performed which shows a nodular pattern of abundant, granular, mildly eosinophilic cells with grooved nuclei with indented nuclear membranes and a chronic inflammation that consists primarily of eosinophils. Immunohistochemical staining reveals numerous cells that stain positive for S100 and CD1a. Which of the cells of the human immune system are responsible for this lesion?", "answer": "Dendritic cells", "options": {"A": "T lymphocytes", "B": "B lymphocytes", "C": "Natural killer cells", "D": "Dendritic cells", "E": "Ciliary epithelium"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old man seeks evaluation from his family physician with a complaint of heartburn, which has been gradually increasing over the last 10 years. The heartburn gets worse after eating spicy foods and improves with antacids. The past medical history is benign. He is a security guard and works long hours at night. He admits to smoking 1.5 packs of cigarettes every day. Upper gastrointestinal endoscopy reveals several gastric ulcers and regions of inflammation. A biopsy is obtained, which revealed gram-negative bacteria colonized on the surface of the regenerative epithelium of the stomach, as shown in the micrograph below. Which of the following bacterial products is responsible for neutralizing the acidity of the stomach?", "answer": "Urease", "options": {"A": "β-lactamase", "B": "Hyaluronidase", "C": "Urease", "D": "Streptokinase", "E": "Prostaglandins"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 32-year-old woman comes to the physician because of a 1-week history of progressively worsening cough with blood-tinged sputum, shortness of breath at rest, and intermittent left-sided chest pain. She has some mild vaginal bleeding since she had a cesarean delivery 6 weeks ago due to premature rupture of membranes and fetal distress at 38 weeks' gestation. She has been exclusively breastfeeding her child. Her temperature is 37°C (98.6°F), pulse is 95/min, respirations are 22/min, and blood pressure is 110/80 mm Hg. Breath sounds are decreased in the left lung base. The fundal height is 20 cm. Pelvic examination shows scant vaginal bleeding. Chest x-ray is shown. Further evaluation is most likely to reveal which of the following?", "answer": "Increased serum β-HCG levels", "options": {"A": "Increased angiotensin converting enzyme levels", "B": "Increased serum β-HCG levels", "C": "Acid fast bacilli in sputum", "D": "Increased carcinoembryonic antigen levels", "E": "Increased brain natriuretic peptide levels"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman presents to her physician concerned about wet spots on the inside part of her dress shirts, which she thinks it may be coming from one of her breasts. She states that it is painless and that the discharge is usually blood-tinged. She denies any history of malignancy in her family and states that she has been having regular periods since they first started at age 13. She does not have any children. The patient has normal vitals and denies any cough, fever. On exam, there are no palpable masses, and the patient does not have any erythema or induration. What is the most likely diagnosis?", "answer": "Intraductal papilloma", "options": {"A": "Fibrocystic changes", "B": "Paget's disease", "C": "Breast abscess", "D": "Ductal carcinoma", "E": "Intraductal papilloma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 54-year-old African American male presents to the emergency department with 1 day history of severe headaches. He has a history of poorly controlled hypertension and notes he hasn't been taking his antihypertensive medications. His temperature is 100.1 deg F (37.8 deg C), blood pressure is 190/90 mmHg, pulse is 60/min, and respirations are 15/min. He is started on a high concentration sodium nitroprusside infusion and transferred to the intensive care unit. His blood pressure eventually improves over the next two days and his headache resolves, but he becomes confused and tachycardic. Labs reveal a metabolic acidosis. Which of the following is the best treatment?", "answer": "Sodium nitrite", "options": {"A": "Methylene blue", "B": "Sodium nitrite", "C": "Bicarbonate", "D": "Glucagon", "E": "Ethanol"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old man is brought to the emergency department because of trauma from a motor vehicle accident. His pulse is 122/min and rapid and thready, the blood pressure is 78/37 mm Hg, the respirations are 26/min, and the oxygen saturation is 90% on room air. On physical examination, the patient is drowsy, with cold and clammy skin. Abdominal examination shows ecchymoses in the right flank. The external genitalia are normal. No obvious external wounds are noted, and the rest of the systemic examination values are within normal limits. Blood is sent for laboratory testing and urinalysis shows 6 RBC/HPF. Hematocrit is 22% and serum creatinine is 1.1 mg/dL. Oxygen supplementation and IV fluid resuscitation are started immediately, but the hypotension persists. The focused assessment with sonography in trauma (FAST) examination shows a retroperitoneal fluid collection. What is the most appropriate next step in management?", "answer": "Take the patient to the OR for an exploratory laparotomy", "options": {"A": "CT of the abdomen and pelvis with contrast", "B": "Take the patient to the OR for an exploratory laparotomy", "C": "Perform an MRI scan of the abdomen and pelvis", "D": "Obtain a retrograde urethrogram", "E": "Perform a diagnostic peritoneal lavage"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old homeless man is brought to the emergency department. He was found unconscious at the park. The patient has a past medical history of IV drug abuse, hepatitis C, alcohol abuse, schizophrenia, and depression. He does not receive normal medical follow up or care. His temperature is 102°F (38.9°C), blood pressure is 97/68 mmHg, pulse is 120/min, respirations are 22/min, and oxygen saturation is 98% on room air. Physical exam demonstrates a diffusely distended abdomen that is dull to percussion with a notable fluid wave. The abdominal exam causes the patient to contract his extremities. Cardiac and pulmonary exam are within normal limits. The patient responds to painful stimuli and smells heavily of alcohol. Which of the following is the best next step in management?", "answer": "Paracentesis", "options": {"A": "Cefotaxime", "B": "Ceftriaxone", "C": "CT abdomen", "D": "Paracentesis", "E": "Ultrasound"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old woman comes to the physician because of a 4-day history of low-grade fever, joint pain, and muscle aches. The day before the onset of her symptoms, she was severely sunburned on her face and arms during a hike with friends. She also reports being unusually fatigued over the past 3 months. Her only medication is a combined oral contraceptive pill. Her temperature is 37.9°C (100.2°F). Examination shows bilateral swelling and tenderness of the wrists and metacarpophalangeal joints. There are multiple nontender superficial ulcers on the oral mucosa. The detection of antibodies directed against which of the following is most specific for this patient's condition?", "answer": "Nuclear Sm proteins", "options": {"A": "Cell nucleus", "B": "Single-stranded DNA", "C": "Fc region of IgG", "D": "Nuclear Sm proteins", "E": "Histones\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old primigravida presents at 36 weeks gestation with vaginal bleeding, mild abdominal pain, and uterine contractions that appeared after bumping into a handrail. The vital signs are as follows: blood pressure 130/80 mm Hg, heart rate 79/min, respiratory rate 12/min, and temperature 36.5℃ (97.7℉). The fetal heart rate was 145/min. Uterine fundus is at the level of the xiphoid process. Slight uterine tenderness and contractions are noted on palpation. The perineum is bloody. The gynecologic examination shows no vaginal or cervical lesions. The cervix is long and closed. Streaks of bright red blood are passing through the cervix. A transabdominal ultrasound shows the placenta to be attached to the lateral uterine wall with a marginal retroplacental hematoma (an approximate volume of 150 ml). The maternal hematocrit is 36%. What is the next best step in the management of this patient?", "answer": "Admit for maternal and fetal monitoring and observation", "options": {"A": "Urgent cesarean delivery", "B": "Induction of vaginal labor", "C": "Admit for maternal and fetal monitoring and observation", "D": "Corticosteroid administration and schedule a cesarean section after", "E": "Manage as an outpatient with modified rest"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 20-year-old man comes to the physician because of decreasing academic performance at his college for the past 6 months. He reports a persistent fear of “catching germs” from his fellow students and of contracting a deadly disease. He finds it increasingly difficult to attend classes. He avoids handshakes and close contact with other people. He states that when he tries to think of something else, the fears “keep returning” and that he has to wash himself for at least an hour when he returns home after going outside. Afterwards he cleans the shower and has to apply disinfectant to his body and to the bathroom. He does not drink alcohol. He used to smoke cannabis but stopped one year ago. His vital signs are within normal limits. He appears anxious. On mental status examination, he is oriented to person, place, and time. In addition to starting an SSRI, which of the following is the most appropriate next step in management?", "answer": "Cognitive-behavioral therapy", "options": {"A": "Motivational interviewing", "B": "Cognitive-behavioral therapy", "C": "Psychodynamic psychotherapy", "D": "Interpersonal therapy", "E": "Group therapy\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-month-old girl presents with recurring skin infections. Past medical history is significant for 3 episodes of acute otitis media since birth. The patient was born at 39 weeks via an uncomplicated, spontaneous transvaginal delivery, but there was delayed umbilical cord separation. She has met all developmental milestones. On physical examination, the skin around her mouth is inflamed and red. Which of the following is most likely responsible for this child’s clinical presentation?", "answer": "Absence of CD18 molecule on the surface of leukocytes", "options": {"A": "Defect in tyrosine kinase", "B": "A microtubule dysfunction", "C": "IL-12 receptor deficiency", "D": "Absence of CD18 molecule on the surface of leukocytes", "E": "Deficiency in NADPH oxidase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is studying gastric secretions in human volunteers. Measurements of gastric activity are recorded after electrical stimulation of the vagus nerve. Which of the following sets of changes is most likely to occur after vagus nerve stimulation?\n $$$ Somatostatin secretion %%% Gastrin secretion %%% Gastric pH $$$", "answer": "↓ ↑ ↓", "options": {"A": "↑ ↑ ↓", "B": "↓ ↑ ↓", "C": "↑ ↑ ↑", "D": "↓ ↓ ↓", "E": "↑ ↓ ↑"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 44-year-old man comes to the physician because of progressive memory loss for the past 6 months. He reports that he often misplaces his possessions and has begun writing notes to remind himself of names and important appointments. He generally feels fatigued and unmotivated, and has poor concentration at work. He has also given up playing soccer because he feels slow and unsteady on his feet. He has also had difficulty swallowing food over the last two weeks. His temperature is 37.8°C (100°F), pulse is 82/min, respirations are 16/min, and blood pressure is 144/88 mm Hg. Examination shows confluent white plaques on the posterior oropharynx. Neurologic examination shows mild ataxia and an inability to perform repetitive rotary forearm movements. Mental status examination shows a depressed mood and short-term memory deficits. Serum glucose, vitamin B12 (cyanocobalamin), and thyroid-stimulating hormone concentrations are within the reference range. Upper esophagogastroduodenoscopy shows streaky, white-grayish lesions. Which of the following is the most likely underlying cause of this patient's neurological symptoms?", "answer": "HIV-related encephalopathy", "options": {"A": "Cerebral toxoplasmosis", "B": "Pseudodementia", "C": "HIV-related encephalopathy", "D": "Frontotemporal dementia", "E": "Primary CNS lymphoma"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 12-year-old male presents to the pediatrician after two days of tea-colored urine which appeared to coincide with the first day of junior high football. He explains that he refused to go back to practice because he was humiliated by the other players due to his quick and excessive fatigue after a set of drills accompanined by pain in his muscles. A blood test revealed elevated creatine kinase and myoglobulin levels. A muscle biopsy was performed revealing large glycogen deposits and an enzyme histochemistry showed a lack of myophosphorylase activity. Which of the following reactions is not occuring in this individuals?", "answer": "Breaking down glycogen to glucose-1-phosphate", "options": {"A": "Converting glucose-6-phosphate to glucose", "B": "Breaking down glycogen to glucose-1-phosphate", "C": "Cleaving alpha-1,6 glycosidic bonds from glycogen", "D": "Creating alpha-1,6 glycosidic bonds in glycogen", "E": "Converting galactose to galactose-1-phosphate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 38-year-old woman presents with progressive muscle weakness. The patient says that symptoms onset a couple of weeks ago and have progressively worsened. She says she hasn’t been able to lift her arms to comb her hair the past few days. No significant past medical history and no current medications. Family history is significant for her mother with scleroderma and an aunt with systemic lupus erythematosus (SLE). On physical examination, strength is 2 out of 5 in the upper extremities bilaterally. There is an erythematous area, consisting of alternating hypopigmentation and hyperpigmentation with telangiectasias, present on the extensor surfaces of the arms, the upper chest, and the neck in a ‘V-shaped’ distribution. Additional findings are presented in the exhibit (see image). Laboratory tests are significant for a positive antinuclear antibody (ANA) and elevated creatinine phosphokinase. Which of the following is the most appropriate first-line treatment for this patient?", "answer": "High-dose corticosteroids", "options": {"A": "Hydroxychloroquine", "B": "Methotrexate", "C": "High-dose corticosteroids", "D": "Intravenous immunoglobulin", "E": "Infliximab"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 20-year-old college student comes to the physician because she has been extremely sad for the past 3 weeks and has to cry constantly. Three weeks ago, her boyfriend left her after they were together for 4 years. She has no appetite and has had a 2.3-kg (5.1-lb) weight loss. She has missed several classes because she could not stop crying or get out of bed. She thinks about her ex-boyfriend all the time. She says that she experienced similar symptoms for about 2 months after previous relationships ended. The patient is 158 cm (5 ft 2 in) tall and weighs 45 kg (100 lb); BMI is 18 kg/m2. Her temperature is 36.1°C (97°F), pulse is 65/min, and blood pressure is 110/60 mm Hg. Physical examination shows no abnormalities. On mental status examination she appears sad and cries easily. Which of the following is the most likely diagnosis?", "answer": "Adjustment disorder with depressed mood", "options": {"A": "Bereavement", "B": "Adjustment disorder with depressed mood", "C": "Major depressive disorder", "D": "Acute stress disorder", "E": "Anorexia nervosa"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-year-old child presents to your office with a chronic cough. His mother states that he has had a cough for the past two weeks that is non-productive along with low fevers of 100.5 F as measured by an oral thermometer. The mother denies any other medical history and states that he has been around one other friend who also has had this cough for many weeks. The patient's vitals are within normal limits with the exception of his temperature of 100.7 F. His chest radiograph demonstrated diffuse interstitial infiltrates. Which organism is most likely causing his pneumonia?", "answer": "Mycoplasma pneumoniae", "options": {"A": "Mycoplasma pneumoniae", "B": "Staphylococcus aureus", "C": "Streptococcus pneumoniae", "D": "Pneumocystis jiroveci", "E": "Streptococcus agalactiae"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-hour-old male newborn has perioral discoloration for the past several minutes. Oxygen by nasal cannula does not improve the cyanosis. He was delivered by cesarean delivery at 37 weeks' gestation to a 38-year-old woman, gravida 3, para 2. Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. The mother has type 2 diabetes mellitus that was well-controlled during the pregnancy. She has not received any immunizations since her childhood. The newborn's temperature is 37.1°C (98.8°F), pulse is 170/min, respirations are 55/min, and blood pressure is 80/60 mm Hg. Pulse oximetry shows an oxygen saturation of 85%. Cardiopulmonary examination shows a 2/6 holosystolic murmur along the lower left sternal border. The abdomen is soft and non-tender. Echocardiography shows pulmonary arteries arising from the posterior left ventricle, and the aorta rising anteriorly from the right ventricle. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Prostaglandin E1 administration", "options": {"A": "Reassurance", "B": "Prostaglandin E1 administration", "C": "Indomethacin administration", "D": "Surgical repair", "E": "Obtain a CT Angiography\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old woman, gravida 3, para 2, at 16 weeks' gestation comes to the physician because of nausea and recurrent burning epigastric discomfort for 1 month. Her symptoms are worse after heavy meals. She does not smoke or drink alcohol. Examination shows a uterus consistent in size with a 16-week gestation. Palpation of the abdomen elicits mild epigastric tenderness. The physician prescribes her medication to alleviate her symptoms. Treatment with which of the following drugs should be avoided in this patient?", "answer": "Misoprostol", "options": {"A": "Pantoprazole", "B": "Misoprostol", "C": "Magnesium hydroxide", "D": "Cimetidine", "E": "Sucralfate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 71-year-old man develops worsening chest pressure while shoveling snow in the morning. He tells his wife that he has a squeezing pain that is radiating to his jaw and left arm. His wife calls for an ambulance. On the way, he received chewable aspirin and 3 doses of sublingual nitroglycerin with little relief of pain. He has borderline diabetes and essential hypertension. He has smoked 15–20 cigarettes daily for the past 37 years. His blood pressure is 172/91 mm Hg, the heart rate is 111/min and the temperature is 36.7°C (98.0°F). On physical examination in the emergency department, he looks pale, very anxious and diaphoretic. His ECG is shown in the image. Troponin levels are elevated. Which of the following is the best next step in the management of this patient condition?", "answer": "Clopidogrel, atenolol, anticoagulation and monitoring", "options": {"A": "Oral nifedipine", "B": "Fibrinolysis", "C": "Clopidogrel, atenolol, anticoagulation and monitoring", "D": "Echocardiography", "E": "CT scan of the chest with contrast"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An obese 52-year-old man is brought to the emergency department because of increasing shortness of breath for the past 8 hours. Two months ago, he noticed a mass on the right side of his neck and was diagnosed with laryngeal cancer. He has smoked two packs of cigarettes daily for 27 years. He drinks two pints of rum daily. He appears ill. He is oriented to person, place, and time. His temperature is 37°C (98.6°F), pulse is 111/min, respirations are 34/min, and blood pressure is 140/90 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 89%. Examination shows a 9-cm, tender, firm subglottic mass on the right side of the neck. Cervical lymphadenopathy is present. His breathing is labored and he has audible inspiratory stridor but is able to answer questions. The lungs are clear to auscultation. Arterial blood gas analysis on room air shows:\npH 7.36\nPCO2 45 mm Hg\nPO2 74 mm Hg\nHCO3- 25 mEq/L\nHe has no advanced directive. Which of the following is the most appropriate next step in management?\"", "answer": "Tracheostomy", "options": {"A": "Tracheal stenting", "B": "Tracheostomy", "C": "Intramuscular epinephrine", "D": "Comfort care measures", "E": "Cricothyroidotomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 87-year-old woman is admitted to the intensive care unit after a neighbor found her lying on the floor at her home. Her respirations are 13/min and shallow. Despite appropriate therapy, the patient dies. Gross examination of the brain at autopsy shows neovascularization and liquefactive necrosis without cavitation in the distribution of the left middle cerebral artery. Histological examination of a brain tissue sample from the left temporal lobe shows proliferation of neural cells that stain positive for glial fibrillary acidic protein. Based on these findings, approximately how much time has most likely passed since the initial injury in this patient?", "answer": "10 days", "options": {"A": "10 days", "B": "12 hours", "C": "25 days", "D": "2 hours", "E": "2 days"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 34-year-old female with a past medical history of a gastric sleeve operation for morbid obesity presents for pre-surgical clearance prior to a knee arthroplasty. Work-up reveals a hemoglobin of 8.7 g/dL, hematocrit of 26.1%, and MCV of 106 fL. With concern for folate deficiency, she is started on high dose folate supplementation, and her follow-up labs are as follows: hemoglobin of 10.1 g/dL, hematocrit of 28.5%, and MCV of 96 fL. She is at risk for which long-term complication?", "answer": "Peripheral neuropathy", "options": {"A": "Neural tube defects", "B": "Macular degeneration", "C": "Peripheral neuropathy", "D": "Hypothyroidism", "E": "Microcytic anemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 50-year-old morbidly obese woman presents to a primary care clinic for the first time. She states that her father recently died due to kidney failure and wants to make sure she is healthy. She works as an accountant, is not married or sexually active, and drinks alcohol occasionally. She currently does not take any medications. She does not know if she snores at night but frequently feels fatigued. She denies any headaches but reports occasional visual difficulties driving at night. She further denies any blood in her urine or increased urinary frequency. She does not engage in any fitness program. She has her period every 2 months with heavy flows. Her initial vital signs reveal that her blood pressure is 180/100 mmHg and heart rate is 70/min. Her body weight is 150 kg (330 lb). On physical exam, the patient has droopy eyelids, a thick neck with a large tongue, no murmurs or clicks on cardiac auscultation, clear lungs, a soft nontender, albeit large abdomen, and palpable pulses in her distal extremities. She can walk without difficulty. A repeat measurement of her blood pressure shows 155/105 mmHg. Which among the following is part of the most appropriate next step in management?", "answer": "Urinalysis", "options": {"A": "Cortisol levels", "B": "Polysomnography", "C": "Renal artery doppler ultrasonography", "D": "Thyroid-stimulating hormone", "E": "Urinalysis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old male was picked up by police in the public library for harassing the patrons and for public nudity. He displayed disorganized speech and believed that the books were the only way to his salvation. Identification was found on the man and his sister was called to provide more information. She described that he recently lost his house and got divorced within the same week although he seemed fine three days ago. The man was sedated with diazepam and chlorpromazine because he was very agitated. His labs returned normal and within three days, he appeared normal, had no recollection of the past several days, and discussed in detail how stressful the past two weeks of his life were. He was discharged the next day. Which of the following is the most appropriate diagnosis for this male?", "answer": "Brief psychotic disorder", "options": {"A": "Brief psychotic disorder", "B": "Schizophreniform disoder", "C": "Schizophrenia", "D": "Schizoid personality disoder", "E": "Schizotypal personality disoder"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old man comes to the clinic complaining of sexual dysfunction. He reports normal sexual function until 4 months ago when his relationship with his wife became stressful due to a death in the family. When asked about the details of his dysfunction, he claims that he is “able to get it up, but just can’t finish the job.” He denies any decrease in libido or erections, endorses morning erections, but an inability to ejaculate. He is an avid cyclist and exercises regularly. His past medical history includes depression and diabetes, for which he takes citalopram and metformin, respectively. A physical examination is unremarkable. What is the most likely explanation for this patient’s symptoms?", "answer": "Damage to the pudendal nerve", "options": {"A": "Autonomic neuropathy secondary to systemic disease", "B": "Damage to the pudendal nerve", "C": "Medication side effect", "D": "Psychological stress", "E": "Testosterone deficiency"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old girl presents with delayed growth, anemia, and jaundice. Her mother denies any history of blood clots in her past, but she says that her mother has also had to be treated for pulmonary embolism and multiple episodes of unexplained pain in the past. Her prenatal history is significant for preeclampsia, preterm birth, and a neonatal intensive care unit (NICU) stay of 6 weeks. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 102/54 mm Hg, heart rate 111/min, and respiratory rate 23/min. On physical examination, the pulses are bounding, the complexion is pale, but breath sounds remain clear. Oxygen saturation was initially 81% on room air, with a new oxygen requirement of 4 L by nasal cannula. Upon further examination, her physician notices that her fingers appear inflamed. A peripheral blood smear demonstrates sickle-shaped red blood cells (RBCs). What is the most appropriate treatment for this patient?", "answer": "Hydroxyurea", "options": {"A": "Hydroxyurea", "B": "Darbepoetin", "C": "Epoetin", "D": "Corticosteroids", "E": "Intravenous immunoglobulin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 35-year-old woman presents for evaluation of symmetric proximal muscle weakness. The patient also presents with a blue-purple discoloration of the upper eyelids accompanied by rashes on the knuckles, as shown in the picture below. What is the most likely cause?", "answer": "Dermatomyositis", "options": {"A": "Polymyositis", "B": "Duchenne muscular dystrophy", "C": "Hypothyroidism", "D": "Inclusion body myositis", "E": "Dermatomyositis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man comes to the physician because of a 1-week history of left-sided chest pain. The pain is worse when he takes deep breaths. Over the past 6 weeks, he had been training daily for an upcoming hockey tournament. He does not smoke cigarettes or drink alcohol but has used cocaine once. His temperature is 37.1°C (98.7°F), pulse is 75/min, and blood pressure is 128/85 mm Hg. Physical examination shows tenderness to palpation of the left chest. An x-ray of the chest is shown. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Naproxen", "options": {"A": "Nitroglycerin", "B": "Alprazolam", "C": "Alteplase", "D": "Heparin", "E": "Naproxen"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A prospective cohort study is conducted to evaluate the risk of pleural mesothelioma in construction workers exposed to asbestos in Los Angeles. Three hundred construction workers reporting current occupational asbestos exposure were followed alongside 300 construction workers without a history of asbestos exposure. After 8 years of follow-up, no statistically significant difference in the incidence of pleural mesothelioma was observed between the two groups (p = 0.13), even after controlling for known mesothelioma risk factors such as radiation, age, and sex. Which of the following is the most likely explanation for the observed results of this study?", "answer": "Latency period", "options": {"A": "Length-time bias", "B": "Lead-time bias", "C": "Latency period", "D": "Observer effect", "E": "Berkson bias"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old woman with history of coronary artery disease status-post coronary artery bypass graft presents with a stroke due to an infarction in the right middle cerebral artery territory. She is admitted to the intensive care unit for neurological monitoring following a successful thrombectomy. Overnight, the patient complains of difficulty breathing, chest pain, and jaw pain. Her temperature is 98.6°F (37°C), blood pressure is 160/80 mmHg, pulse is 100/min, respirations are 30/min, and oxygen saturation is 90% on 2L O2 via nasal cannula. Rales are heard in the lower lung bases. Electrocardiogram reveals left ventricular hypertrophy with repolarization but no acute ST or T wave changes. Troponin is 2.8 ng/mL. Chest radiograph reveals Kerley B lines. After administration of oxygen, aspirin, carvedilol, and furosemide, the patient improves. The next troponin is 3.9 ng/mL. Upon further discussion with the consulting cardiologist and neurologist, a heparin infusion is started. After transfer to a general medicine ward floor four days later, the patient complains of a headache. The patient's laboratory results are notable for the following:\n\nHemoglobin: 11 g/dL\nHematocrit: 36%\nLeukocyte count: 11,000 /mm^3 with normal differential\nPlatelet count: 130,000 /mm^3\n\nOn admission, the patient's platelet count was 300,000/mm^3. What medication is appropriate at this time?", "answer": "Argatroban", "options": {"A": "Argatroban", "B": "Enoxaparin", "C": "Dalteparin", "D": "Protamine", "E": "Tinzaparin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-day-old male infant is brought to a pediatrician by his parents with concerns of poor feeding and excessive perspiration for one week. On physical examination, his temperature is 37.7°C (99.8°F), pulse rate is 190/min, and respiratory rate is 70/min. Mild cyanosis is present over the lips, and over the nail beds. Oxygen is provided and his oxygen saturation is carefully monitored. The pediatrician orders a bedside echocardiogram of the infant. It reveals a single arterial trunk arising from 2 normally formed ventricles. The arterial trunk is separated from the ventricles by a single semilunar valve. There is a defect in the interventricular septum, and the arterial trunk overrides the defect. Which of the following congenital heart diseases can also present with similar clinical features?", "answer": "Double-inlet ventricle with unobstructed pulmonary flow", "options": {"A": "Double-inlet ventricle with unobstructed pulmonary flow", "B": "Infracardiac total anomalous pulmonary venous return", "C": "Severe Ebstein anomaly", "D": "Transposition of the great arteries with ventricular septal defect and pulmonary stenosis", "E": "Pulmonary atresia with intact ventricular septum"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old white male is brought to the emergency department after being struck by a car. He complains of pain in his right leg and left wrist, and slowly recounts how he was hit by a car while being chased by a lion. In between sentences of the story, he repeatedly complains of dry mouth and severe hunger and requests something to eat and drink. His mother arrives and is very concerned about this behavior, noting that he has been withdrawn lately and doing very poorly in school the past several months. Notable findings on physical exam include conjunctival injection bilaterally and a pulse of 107. What drug is this patient most likely currently abusing?", "answer": "Marijuana", "options": {"A": "Cocaine", "B": "Phencylidine (PCP)", "C": "Benzodiazepines", "D": "Marijuana", "E": "Heroin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old woman with hypertension comes to the physician because of swelling and pain in both legs for the past year. The symptoms are worse at night and improve in the morning. Current medications include losartan and metoprolol. Her temperature is 36°C (96.8°F), pulse is 67/min, and blood pressure is 142/88 mm Hg. Examination shows normal heart sounds; there is no jugular venous distention. Her abdomen is soft and the liver edge is not palpable. Examination of the lower extremities shows bilateral pitting edema and prominent superficial veins. The skin is warm and there is reddish-brown discoloration of both ankles. Laboratory studies show a normal serum creatinine and normal urinalysis. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Increased venous valve reflux", "options": {"A": "Decreased lymphatic flow", "B": "Decreased intravascular oncotic pressure", "C": "Decreased arteriolar resistance", "D": "Increased venous valve reflux", "E": "Increased capillary permeability"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old post-menopausal female presents to her gynecologist with vaginal bleeding. Her last period was over 10 years ago. Dilation and curettage reveals endometrial carcinoma so she is scheduled to undergo a total abdominal hysterectomy and bilateral salpingo-oophorectomy. During surgery, the gynecologist visualizes paired fibrous structures arising from the cervix and attaching to the lateral pelvic walls at the level of the ischial spines. Which of the following vessels is found within each of the paired visualized structure?", "answer": "Uterine artery", "options": {"A": "Superior vesical artery", "B": "Vaginal artery", "C": "Artery of Sampson", "D": "Uterine artery", "E": "Ovarian artery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 56-year-old woman presents with sudden-onset severe headache, nausea, vomiting, and neck pain for the past 90 minutes. She describes her headache as a ‘thunderclap’, followed quickly by severe neck pain and stiffness, nausea and vomiting. She denies any loss of consciousness, seizure, or similar symptoms in the past. Her past medical history is significant for an episode 6 months ago where she suddenly had trouble putting weight on her right leg, which resolved within hours. The patient denies any history of smoking, alcohol or recreational drug use. On physical examination, the patient has significant nuchal rigidity. Her muscle strength in the lower extremities is 4/5 on the right and 5/5 on the left. The remainder of the physical examination is unremarkable. A noncontrast CT scan of the head is normal. Which of the following is the next best step in the management of this patient?", "answer": "Lumbar puncture", "options": {"A": "IV tPA", "B": "Lumbar puncture", "C": "T1/T2 MRI of the head", "D": "Diffusion-weighted magnetic resonance imaging of the brain", "E": "Placement of a ventriculoperitoneal (VP) shunt"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 1-minute-old newborn is being examined by the pediatric nurse. The nurse auscultates the heart and determines that the heart rate is 89/min. The respirations are spontaneous and regular. The chest and abdomen are both pink while the tips of the fingers and toes are blue. When the newborn’s foot is slapped the face grimaces and he cries loud and strong. When the arms are extended by the nurse they flex back quickly. What is this patient’s Apgar score?", "answer": "8", "options": {"A": "5", "B": "6", "C": "8", "D": "9", "E": "10"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old man presents with back pain which began 3 days ago when he was lifting heavy boxes. The pain radiates from the right hip to the back of the thigh. The pain is exacerbated when he bends at the waist. He rates the severity of the pain as 6 out of 10. The patient has asthma and mitral insufficiency due to untreated rheumatic fever in childhood. He has a smoking history of 40 pack-years. His family history is remarkable for rheumatoid arthritis, diabetes, and hypertension. Vital signs are within normal limits. On physical examination, the pain is elicited when the patient is asked to raise his leg without extending his knee. The patient has difficulty walking on his heels. Peripheral pulses are equal and brisk bilaterally. No hair loss, temperature changes, or evidence of peripheral vascular disease is observed. Which of the following is considered the best management option for this patient?", "answer": "Over-the-counter NSAIDs", "options": {"A": "Stenting", "B": "Observation", "C": "Referral for surgery", "D": "Prescription of opioids", "E": "Over-the-counter NSAIDs"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old man is brought to the emergency department with minor injuries sustained in a motor vehicle accident. He says that he is fine. He also witnessed the death of a teenage girl in the accident who was his sister’s friend. He is able to return to work within a few days. A month later, he presents being withdrawn and increasingly irritable. He says recently he has been experiencing depressed moods and higher anxiety than usual. He says that he feels guilty about the girl’s death, stating that he could have saved her if only he had acted quicker. He adds that he became extremely anxious while driving by a car accident on the freeway recently, and that, even when watching television or a movie, he feels panicked during a car crash scene. Which of the following is the most likely diagnosis in this patient?", "answer": "Post-traumatic stress disorder", "options": {"A": "Adjustment disorder", "B": "Acute stress disorder", "C": "Generalized anxiety disorder", "D": "Panic disorder", "E": "Post-traumatic stress disorder"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old woman, gravida 2, para 1, at 36 weeks' gestation comes to the physician because of irritability, palpitations, heat intolerance, and frequent bowel movements for the last 5 months. She has received no prenatal care. Her pulse is 118/min and blood pressure is 133/80 mm Hg. She appears anxious. There is a fine tremor in the hands and ophthalmologic examination shows bilateral exophthalmos. The skin is warm and moist to touch. This patient’s child is most likely to have which of the following complications at birth?", "answer": "Microcephaly and stridor", "options": {"A": "Bradycardia and annular rash", "B": "Umbilical hernia and erosive scalp lesion", "C": "Macrosomia and shoulder dystocia", "D": "Mechanical holosystolic murmur and tetany", "E": "Microcephaly and stridor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 53-year-old multiparous woman is scheduled to undergo elective sling surgery for treatment of stress incontinence. She has frequent loss of small amounts of urine when she coughs or laughs, despite attempts at conservative treatment. The physician inserts trocars in the obturator foramen bilaterally to make the incision and passes a mesh around the pubic bones and underneath the urethra to form a sling. During the procedure, the physician accidentally injures a nerve in the obturator foramen. The function of which of the following muscles is most likely to be affected following the procedure?", "answer": "Adductor longus", "options": {"A": "Obturator internus", "B": "Adductor longus", "C": "Tensor fascia latae", "D": "Transversus abdominis", "E": "Semitendinosus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old woman is on hospital day 2 in the medical intensive care unit. She was admitted from the emergency department for a 2-day history of shortness of breath and fever. In the emergency department, her temperature is 39.4°C (103.0°F), the pulse is 120/min, the blood pressure is 94/54 mm Hg, the respiratory rate is 36/min, and oxygen saturation was 82% while on 4L of oxygen via a non-rebreather mask. Chest X-ray shows a right lower lobe consolidation. She was intubated, sedated, and started on broad-spectrum antibiotics for sepsis of pulmonary origin and intravenous norepinephrine for blood pressure support. Since then, her clinical condition has been stable, though her vasopressor and oxygen requirements have not improved. Today, her physician is called to the bedside because her nurse noted some slow bleeding from her intravenous line sites and around her urinary catheter. Which of the following most likely represents the results of coagulation studies for this patient?", "answer": "D-dimer: elevated, fibrinogen level: low, platelet count: low", "options": {"A": "D-dimer: negative, fibrinogen level: normal, platelet count: normal", "B": "D-dimer: elevated, fibrinogen level: low, platelet count: low", "C": "D-dimer: negative, fibrinogen level: elevated, platelet count: elevated", "D": "D-dimer: elevated, fibrinogen level: normal, platelet count: normal", "E": "D-dimer: negative, fibrinogen level: low, platelet count: low"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A newborn undergoing the standard screening tests is found to have a positive test for reducing sugars. Further testing is performed and reveals that the patient does not have galactosemia, but rather is given a diagnosis of fructosuria. What levels of enzymatic activity are altered in this patient?", "answer": "Hexokinase increased; fructokinase decreased", "options": {"A": "Hexokinase increased; fructokinase decreased", "B": "Hexokinase decreased; fructokinase increased", "C": "Hexokinase increased; fructokinase increased", "D": "Hexokinase decreased; fructokinase decreased", "E": "Hexokinase unchanged; fructokinase unchanged"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 53-year-old man is brought to the emergency department because of wheezing and shortness of breath that began 1 hour after he took a new medication. Earlier in the day he was diagnosed with stable angina pectoris and prescribed a drug that irreversibly inhibits cyclooxygenase-1 and 2. He has chronic rhinosinusitis and asthma treated with inhaled β-adrenergic agonists and corticosteroids. His respirations are 26/min. Examination shows multiple small, erythematous nasal mucosal lesions. After the patient is stabilized, therapy for primary prevention of coronary artery disease should be switched to a drug with which of the following mechanisms of action?", "answer": "Blockage of P2Y12 component of ADP receptors", "options": {"A": "Inhibition of vitamin K epoxide reductase", "B": "Blockage of P2Y12 component of ADP receptors", "C": "Direct inhibition of Factor Xa", "D": "Sequestration of Ca2+ ions", "E": "Potentiation of antithrombin III"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 6-year-old boy is brought to the physician by his parents because of right lower extremity weakness, worsening headaches, abdominal pain, dark urine, and a 5-kg (11-lb) weight loss for the past 2 months. His teachers report that he has not been paying attention in class and his grades have been worsening. He has a history of infantile seizures. Physical examination shows a palpable abdominal mass and left costovertebral angle tenderness. Neurological exam shows decreased strength of the right lower limb. He has several acne-like angiofibromas around the nose and cheeks. Further evaluation is most likely to show which of the following?", "answer": "Subependymal giant cell astrocytoma", "options": {"A": "Port wine stain", "B": "Pheochromocytoma", "C": "Lisch nodules", "D": "Subependymal giant cell astrocytoma", "E": "Vestibular schwannoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old diabetic male presents to your clinic for right ear pain. The patient reports noting worsening right ear pain for three weeks, purulent otorrhea initially which has resolved, and facial asymmetry for the past several days. He reports being poorly compliant with his diabetes medication regimen. His temperature is 100.4 deg F (38 deg C), blood pressure is 140/90 mmHg, pulse is 90/min, and respirations are 18/min. On physical exam, the patient’s right external auditory canal is noted to have granulation tissue at the bony cartilaginous junction. He is also noted to have right facial droop. Which of the following is the best next step in treatment?", "answer": "Intravenous ciprofloxacin for 6 weeks", "options": {"A": "Oral amoxicillin-clavulanic acid for 10 days", "B": "Intravenous ciprofloxacin for 6 weeks", "C": "Topical polymyxin and neosporin for 14 days", "D": "Hyperbaric oxygen treatment for 4 weeks", "E": "Surgical intervention"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 66-year-old man weighing 50 kg (110 lb) is admitted to the hospital because of sepsis complicated by acute respiratory distress syndrome. The physician decides to initiate total parenteral nutrition and prescribes short-term hypocaloric intake of 20 kcal/kg/day with 20% of the total energy requirement provided by proteins and 30% provided by fats. The physician calculates that a total volume of 1100 mL/day should be infused during the parenteral nutrition therapy to maintain fluid balance. A colloid containing 10 g/dL of albumin and an emulsion with a fat concentration of 33 g/dL are used to prepare parenteral nutrition modules. Which of the following is the most appropriate module to meet the carbohydrate requirement in this patient over the next 24 hours?", "answer": "500 mL of 25% dextrose solution", "options": {"A": "500 mL of 10% dextrose solution", "B": "250 mL of 50% dextrose solution", "C": "750 mL of 25% dextrose solution", "D": "750 mL of 10% dextrose solution", "E": "500 mL of 25% dextrose solution"}, "meta_info": "step1", "answer_idx": "E"}
{"question": " A 35-year-old woman who was recently ill with an upper respiratory infection presents to the emergency department with weakness in her lower limbs and difficulty breathing. Her symptoms began with a burning sensation in her toes along with numbness. She claims that the weakness has been getting worse over the last few days and now involving her arms and face. Currently, she is unable to get up from the chair without some assistance. Her temperature is 37.0°C (98.6°F), the blood pressure is 145/89 mm Hg, the heart rate is 99/min, the respiratory rate is 12/min, and the oxygen saturation is 95% on room air. On physical examination, she has diminished breath sounds on auscultation of bilateral lung fields with noticeably poor inspiratory effort. Palpation of the lower abdomen reveals a palpable bladder. Strength is 3 out of 5 symmetrically in the lower extremities bilaterally. The sensation is intact. What is the most likely diagnosis?", "answer": "Guillain-Barré syndrome", "options": {"A": "Acute disseminated encephalomyelitis", "B": "Adrenoleukodystrophy", "C": "Guillain-Barré syndrome", "D": "Multiple sclerosis", "E": "Myasthenia Gravis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 75-year-old man is brought to the emergency department after 2 days of severe diffuse abdominal pain, nausea, vomiting, and lack of bowel movements, which has led him to stop eating. He has a history of type-2 diabetes mellitus, hypertension, and chronic pulmonary obstructive disease. Upon admission, his vital signs are within normal limits and physical examination shows diffuse abdominal tenderness, distention, lack of bowel sounds, and an empty rectal ampulla. After initial fluid therapy and correction of moderate hypokalemia, the patient’s condition shows mild improvement. His abdominal plain film is taken and shown. Which of the following is the most appropriate concomitant approach?", "answer": "Nasogastric decompression", "options": {"A": "Initiate pain management with morphine", "B": "Initiate intravenous metoclopramide", "C": "Nasogastric decompression", "D": "Exploratory surgery", "E": "Gastrografin enema"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 13-year-old girl is brought to the outpatient clinic by her parents with a complaint of episodic spasm in her fingers for the past few months. Upon further questioning, her mother notes that the girl has not been doing well at school. She also believes that the girl is shorter than the other children in her class. On examination, her pulse is 72/min, temperature 37.6°C (99.7°F), respiratory rate 16/min, and blood pressure 120/88 mm Hg. The girl has short 4th and 5th fingers on both hands, a round face, and discolored teeth. Her height is 135 cm (4 ft 5 in) and she weighs 60 kg (132 lb). Investigation reports show the following values:\nHemoglobin (Hb%) 12.5 g/dL\nWhite blood cell total count 10,000/mm3\nPlatelets 260,000/mm3\nCalcium, serum (Ca2+) 4.0 mg/dL\nSerum albumin 4.0 g/dL\nAlanine aminotransferase (ALT), serum 15 U/L\nAspartate aminotransferase (AST), serum 8 U/L\nSerum creatinine 0.5 mg/dL\nUrea 27 mg/dL\nSodium 137 mEq/L\nPotassium 4.5 mEq/L\nMagnesium 2.5 mEq/L\nParathyroid hormone, serum, N-terminal 930 pg/mL (normal: 230-630 pg/mL)\nSerum vitamin D 45 ng/dL\nWhich of the following is the mode of inheritance of the disease this patient has?", "answer": "Autosomal dominant", "options": {"A": "X-linked recessive", "B": "Autosomal dominant", "C": "Mitochondrial inheritance", "D": "X linked dominant", "E": "Autosomal recessive"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old man presents to the emergency department for bizarre behavior. The patient had boarded up his house and had been refusing to leave for several weeks. The police were called when a foul odor emanated from his property prompting his neighbors to contact the authorities. Upon questioning, the patient states that he has been pursued by elves for his entire life. He states that he was tired of living in fear, so he decided to lock himself in his house. The patient is poorly kempt and has very poor dentition. The patient has a past medical history of schizophrenia which was previously well controlled with olanzapine. The patient is restarted on olanzapine and monitored over the next several days. Which of the following needs to be monitored long term in this patient?", "answer": "HbA1c levels", "options": {"A": "CBC", "B": "ECG", "C": "HbA1c levels", "D": "Monitoring for acute dystonia", "E": "Renal function studies"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 9-year-old boy with cystic fibrosis (CF) presents to the clinic with fever, increased sputum production, and cough. The vital signs include: temperature 38.0°C (100.4°F), blood pressure 126/74 mm Hg, heart rate 103/min, and respiratory rate 22/min. His physical examination is significant for short stature, thin body frame, decreased breath sounds bilateral, and a 2/6 holosystolic murmur heard best on the upper right sternal border. His pulmonary function tests are at his baseline, and his sputum cultures reveal Pseudomonas aeruginosa. What is the best treatment option for this patient?", "answer": "Inhaled tobramycin for 28 days", "options": {"A": "Inhaled tobramycin for 28 days", "B": "Dornase alfa 2.5 mg as a single-use", "C": "Oral cephalexin for 14 days", "D": "Minocycline for 28 days", "E": "Sulfamethoxazole and trimethoprim for 14 days"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 66-year-old man is brought to the emergency department after a motor vehicle accident. The patient was a restrained passenger in a car that was struck on the passenger side while crossing an intersection. In the emergency department, he is alert and complaining of abdominal pain. He has a history of hyperlipidemia, gastroesophageal reflux disease, chronic kidney disease, and perforated appendicitis for which he received an interval appendectomy four years ago. His home medications include rosuvastatin and lansoprazole. His temperature is 99.2°F (37.3°C), blood pressure is 120/87 mmHg, pulse is 96/min, and respirations are 20/min. He has full breath sounds bilaterally. He is tender to palpation over the left 9th rib and the epigastrium. He is moving all four extremities. His FAST exam reveals fluid in Morrison's pouch.\n\nThis patient is most likely to have which of the following additional signs or symptoms?", "answer": "Shoulder pain", "options": {"A": "Pain radiating to the back", "B": "Gross hematuria", "C": "Shoulder pain", "D": "Muffled heart sounds", "E": "Free air on chest radiograph"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old girl is brought to the physician because her mother is concerned that she has been talking to an imaginary friend for 2 months. The child calls her friend 'Lucy' and says “Lucy is my best friend”. The child has multiple conversation and plays with the 'Lucy' throughout the day. The girl attends preschool regularly. She can copy a circle, tells stories, and can hop on one foot. Her maternal uncle has schizophrenia. Her parents are currently divorcing. The child's father has a history of illicit drug use. Physical examination shows no abnormalities. The mother is concerned about whether the child is acting out because of the divorce. Which of the following is the most appropriate next best step in management?", "answer": "Reassure the mother", "options": {"A": "Screen urine for drugs", "B": "Perform MRI of the brain", "C": "Inform Child Protective Services", "D": "Schedule psychiatry consult", "E": "Reassure the mother"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 33-year-old man presents to the emergency department after an episode of syncope. He states that for the past month ever since starting a new job he has experienced an episode of syncope or near-syncope every morning while he is getting dressed. The patient states that he now gets dressed, shaves, and puts on his tie sitting down to avoid falling when he faints. He has never had this before and is concerned it is stress from his new job as he has been unemployed for the past 5 years. He is wondering if he can get a note for work since he was unable to head in today secondary to his presentation. The patient has no significant past medical history and is otherwise healthy. His temperature is 99.2°F (37.3°C), blood pressure is 122/83 mmHg, pulse is 92/min, respirations are 16/min, and oxygen saturation is 100% on room air. Cardiopulmonary and neurologic exams are within normal limits. An initial ECG and laboratory values are unremarkable as well. Which of the following is the most likely diagnosis?", "answer": "Carotid hypersensitivity syndrome", "options": {"A": "Anxiety", "B": "Aortic stenosis", "C": "Carotid hypersensitivity syndrome", "D": "Hypertrophic obstructive cardiomyopathy", "E": "Malingering"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 42-year-old male presents to your office with cellulitis on his leg secondary to a dog bite. You suspect that the causative agent is a small, facultatively anaerobic, Gram-negative rod sensitive to penicillin with clavulanate. When you ask the patient how the bite occurred, the patient explains that he had a fight with his wife earlier in the day. Frustrated with his wife, he yelled at the family pet, who bit him on the leg. Which of the following defense mechanisms was this patient employing at the time of his injury?", "answer": "Displacement", "options": {"A": "Projection", "B": "Reaction formation", "C": "Regression", "D": "Repression", "E": "Displacement"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-year-old boy and his siblings are referred to a geneticist for evaluation of a mild but chronic hemolytic anemia that has presented with fatigue, splenomegaly, and scleral icterus. Coombs test is negative and blood smear does not show any abnormal findings. An enzymatic panel is assayed, and pyruvate kinase is found to be mutated on both alleles. The geneticist explains that pyruvate kinase functions in glycolysis and is involved in a classic example of feed-forward regulation. Which of the following metabolites is able to activate pyruvate kinase?", "answer": "Fructose-1,6-bisphosphate", "options": {"A": "Glucose-6-phosphate", "B": "Fructose-1,6-bisphosphate", "C": "Glyceraldehyde-3-phosphate", "D": "ATP", "E": "Alanine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 63-year-old woman, gravida 0, para 0 comes to the physician because of a 3-month history of abdominal distension, constipation, and weight loss. She has a history of endometriosis. Pelvic examination shows a nontender, irregular, left adnexal mass. Her serum level of CA-125 is elevated. Serum concentrations of human chorionic gonadotropin and alpha-fetoprotein are within the reference ranges. Microscopic examination of the mass is most likely to show which of the following findings?", "answer": "Atypical epithelial cells along with psammoma bodies", "options": {"A": "Large undifferentiated germ cells with clear cytoplasm", "B": "Flattened, cuboidal cells along with Schiller-Duval bodies", "C": "Small, round cells that form Call-Exner bodies", "D": "Atypical epithelial cells along with psammoma bodies", "E": "Spindle-shaped stromal cells along with signet ring cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Three days after undergoing open surgery to repair a bilateral inguinal hernia, a 66-year-old man has new, intermittent upper abdominal discomfort that worsens when he walks around. He also has new shortness of breath that resolves with rest. There were no complications during surgery or during the immediate postsurgical period. Ambulation was restarted on the first postoperative day. He has type 2 diabetes mellitus, hypercholesterolemia, and hypertension. He has smoked one pack of cigarettes daily for 25 years. Prior to admission, his medications included metformin, simvastatin, and lisinopril. His temperature is 37°C (98.6°F), pulse is 80/min, respirations are 16/min, and blood pressure is 129/80 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. The abdomen is soft and shows two healing surgical scars with moderate serous discharge. Cardiopulmonary examination shows no abnormalities. An ECG at rest shows no abnormalities. Cardiac enzyme levels are within the reference range. An x-ray of the chest and abdominal ultrasonography show no abnormalities. Which of the following is the most appropriate next step in diagnosis?", "answer": "Cardiac pharmacological stress test", "options": {"A": "Obtain serum D-dimer level", "B": "Magnetic resonance imaging of the abdomen", "C": "Culture swab from the surgical site", "D": "Coronary angiography", "E": "Cardiac pharmacological stress test"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 69-year-old male presents to his primary care physician for a checkup. He has not seen a doctor in 15 years and thought he may need an exam. The patient’s past medical history is unknown and he is not currently taking any medications. The patient lives on a rural farm alone and has since he was 27 years of age. The patient works as a farmer and never comes into town as he has all his supplies delivered to him. The patient is oddly adorned in an all-denim ensemble, rarely makes eye contact with the physician, and his responses are very curt. A physical exam is performed and is notable for an obese man with a S3 heart sound on cardiac exam. The patient is informed that further diagnostic testing may be necessary and that it is recommended that he begin taking lisinopril and hydrochlorothiazide for his blood pressure of 155/95 mmHg. Which of the following is the most likely personality disorder that this patient suffers from?", "answer": "Schizoid", "options": {"A": "Schizoid", "B": "Schizotypal", "C": "Paranoid", "D": "Avoidant", "E": "Antisocial"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "You are developing a new diagnostic test to identify patients with disease X. Of 100 patients tested with the gold standard test, 10% tested positive. Of those that tested positive, the experimental test was positive for 90% of those patients. The specificity of the experimental test is 20%. What is the positive predictive value of this new test?", "answer": "11%", "options": {"A": "90%", "B": "10%", "C": "11%", "D": "95%", "E": "20%"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old woman presents with substernal chest pain. She says that the symptoms began 2 hours ago and have not improved. She describes the pain as severe, episodic, and worse with exertion. She reports that she has had multiple similar episodes that have worsened and increased in frequency over the previous 4 months. Past medical history is significant for diabetes and hypertension, both managed medically. The vital signs include temperature 37.0°C (98.6°F), blood pressure 150/100 mm Hg, pulse 80/min, and respiratory rate 15/min. Her serum total cholesterol is 280 mg/dL and high-density lipoprotein (HDL) is 30 mg/dL. The electrocardiogram (ECG) shows ST-segment depression on multiple chest leads. Coronary angiography reveals 75% narrowing of her left main coronary artery. In which of the following anatomical locations is a mural thrombus most likely to form in this patient?", "answer": "Left ventricle", "options": {"A": "Left atrium", "B": "Aorta", "C": "Right atrium", "D": "Left ventricle", "E": "Right ventricle"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-month-old boy is brought to the physician because of fever and a cough for 3 days. His mother reports that he has had multiple episodes of loose stools over the past 3 months. He has been treated for otitis media 4 times and bronchiolitis 3 times during the past 3 months. He was born at 37 weeks' gestation and the neonatal period was uncomplicated. He is at the 10th percentile for height and 3rd percentile for weight. His temperature is 38.3°C (100.9°F), pulse is 126/min, and respirations are 35/min. Examination shows an erythematous scaly rash over the trunk and extremities. There are white patches on the tongue and buccal mucosa that bleed when scraped. Inspiratory crackles are heard in the right lung base. An x-ray of the chest shows an infiltrate in the right lower lobe and an absent thymic shadow. Which of the following is the most likely diagnosis?", "answer": "Severe combined immunodeficiency", "options": {"A": "Wiskott-Aldrich syndrome", "B": "Severe combined immunodeficiency", "C": "Leukocyte adhesion deficiency", "D": "Chronic granulomatous disease", "E": "X-linked agammaglobulinemia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man presents the urgent care clinic with a one-week history of diffuse bone pain and generalized weakness. He was diagnosed with end-stage renal disease 6 months ago and is currently on dialysis. His wife, who is accompanying him today, adds that he is not compliant with his medicines. He has been diabetic for the last 10 years and hypertensive for the last 7 years. He has smoked 4–5 cigarettes per day for 30 years but does not drink alcohol. His family history is insignificant. On examination, the patient has a waddling gait. Hypotonia of all the limbs is evident on neurologic examination. Diffuse bone tenderness is remarkable. X-ray of his legs reveal osteopenia and osseous resorption. The final step of activation of the deficient vitamin in this patient occurs by which of the following enzymes?", "answer": "1-α-hydroxylase", "options": {"A": "7-α-hydroxylase", "B": "1-α-hydroxylase", "C": "α-1-antitrypsin", "D": "α-Glucosidase", "E": "24,25 hydroxylase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 94-year-old woman is brought to the emergency department after she was found unresponsive and febrile at her home. Her son reports that she had an acute episode of coughing while having breakfast the day before. Six days after admission, the patient develops progressive tachypnea and a gradual decrease in oxygen saturation, despite ventilation with supplemental oxygen. Physical examination shows coarse bilateral breath sounds. An x-ray of the chest shows opacities in all lung fields. Despite appropriate care, the patient dies two days later. A photomicrograph of a specimen of the lung obtained at autopsy is shown. This patient's pulmonary condition is most likely associated with which of the following pathophysiologic changes?", "answer": "Increased pulmonary shunt fraction", "options": {"A": "Increased pulmonary shunt fraction", "B": "Increased pulmonary wedge pressure", "C": "Increased mixed venous oxygen saturation", "D": "Increased pulmonary compliance", "E": "Decreased pulmonary artery pressure\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old man comes to the emergency department because of chest pain for the last 3 hours. He describes the pain as a sharp, substernal chest pain that radiates to the right shoulder; he says “Please help me. I'm having a heart attack.” He has been admitted to the hospital twice over the past week for evaluation of shortness of breath and abdominal pain but left the hospital the following day on both occasions. The patient does not smoke or drink alcohol but is a known user of intravenous heroin. He has been living in a homeless shelter for the past 2 weeks after being evicted from his apartment for failure to pay rent. His temperature is 37.6°C (99.6°F), pulse is 90/min, respirations are 18/min, and blood pressure is 125/85 mm Hg. The patient seems anxious and refuses a physical examination of his chest. His cardiac troponin I concentration is 0.01 ng/mL (N = 0–0.01). An ECG shows a normal sinus rhythm with nonspecific ST-T wave changes. While the physician is planning to discharge the patient, the patient reports numbness in his arm and insists on being admitted to the ward. On the following day, the patient leaves the hospital without informing the physician or the nursing staff. Which of the following is the most likely diagnosis?", "answer": "Malingering", "options": {"A": "Conversion disorder", "B": "Factitious disorder", "C": "Malingering", "D": "Illness anxiety disorder", "E": "Somatic symptom disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old man presents to the emergency department with increasing shortness of breath and mild chest discomfort. One week ago he developed cold-like symptoms, including a mild fever, headache, and occasional night sweats. He noticed that he required 2 additional pillows in order to sleep comfortably. Approximately 1-2 nights ago, he was severely short of breath, causing him to awaken from sleep which frightened him. He reports gaining approximately 6 pounds over the course of the week without any significant alteration to his diet. He says that he feels short of breath after climbing 1 flight of stairs or walking less than 1 block. Previously, he was able to climb 4 flights of stairs and walk 6-7 blocks with mild shortness of breath. Medical history is significant for coronary artery disease (requiring a left anterior descending artery stent 5 years ago and dual antiplatelet therapy), heart failure with reduced ejection fraction, hypertension, hyperlipidemia, and type II diabetes. He drinks 2 alcoholic beverages daily and has smoked 1 pack of cigarettes daily for the past 35 years. His temperature is 98.6°F (37°C), blood pressure is 145/90 mmHg, pulse is 102/min, and respirations are 20/min. On physical exam, the patient has a positive hepatojugular reflex, a third heart sound, crackles in the lung bases, and pitting edema up to the mid-thigh bilaterally. Which of the following is the best next step in management?", "answer": "Bumetanide", "options": {"A": "Bumetanide", "B": "Carvedilol", "C": "Dopamine", "D": "Milrinone", "E": "Nitroprusside"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old man presents to his primary care provider complaining of leg pain with exertion for the past 6 months. He notices that he has bilateral calf cramping with walking. He states that it is worse in his right calf than in his left, and it goes away when he stops walking. He has also noticed that his symptoms are progressing and that this pain is occurring sooner than before. His medical history is remarkable for type 2 diabetes mellitus and 30-pack-year smoking history. His ankle-brachial index (ABI) is found to be 0.80. Which of the following can be used as initial therapy for this patient's condition?", "answer": "Cilostazol", "options": {"A": "Endovascular revascularization", "B": "Duloxetine", "C": "Heparin", "D": "Cilostazol", "E": "Arthroscopic resection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 59-year-old man presents to the health clinic for evaluation of severe itching for the past week. The itching is worse at night while lying in bed. The patient has a past medical history of hyperlipidemia, atrial fibrillation, and colon cancer. The patient takes rivaroxaban, simvastatin, and aspirin. The patient has a surgical history of colon resection, appendectomy, and tonsillectomy. He drinks a 6-pack of beer almost every night of the week. He smokes 2 packs of cigarettes daily and has been living at a homeless shelter for the past 6 months. Examination of the skin shows small crusted sores and superficial, wavy gray lines along the wrists and interdigital spaces of both hands as seen in the image. Small vesicles are also present along with excoriations. Which of the following is the most appropriate treatment option for this patient?", "answer": "Permethrin", "options": {"A": "Permethrin", "B": "Ivermectin", "C": "Acyclovir", "D": "Penicillin G", "E": "Dicloxacillin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 26-year-old G1P0 woman is brought to the emergency room by her spouse for persistently erratic behavior. Her spouse reports that she has been sleeping > 1 hour a night, and it sometimes seems like she’s talking to herself. She has maxed out their credit cards on baby clothes. The patient’s spouse reports this has been going on for over a month. Since first seeing a physician, she has been prescribed multiple first and second generation antipsychotics, but the patient’s spouse reports that her behavior has failed to improve. Upon examination, the patient is speaking rapidly and occasionally gets up to pace the room. She reports she is doing “amazing,” and that she is “so excited for the baby to get here because I’m going to be the best mom.” She denies illicit drug use, audiovisual hallucinations, or suicidal ideation. The attending psychiatrist prescribes a class of medication the patient has not yet tried to treat the patient’s psychiatric condition. In terms of this new medication, which of the following is the patient’s newborn most likely at increased risk for?", "answer": "Right ventricular atrialization", "options": {"A": "Attention deficit hyperactivity disorder", "B": "Caudal regression syndrome", "C": "Ototoxicity", "D": "Renal defects", "E": "Right ventricular atrialization"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old woman presents to her primary care physician for knee pain. She states that she has been experiencing a discomfort and pain in her left knee that lasts for several hours but tends to improve with use. She takes ibuprofen occasionally which has been minimally helpful. She states that this pain is making it difficult for her to work as a cashier. Her temperature is 98.6°F (37.0°C), blood pressure is 117/58 mmHg, pulse is 90/min, respirations are 14/min, and oxygen saturation is 97% on room air. Physical exam reveals a stable gait that the patient claims causes her pain. The patient has a non-pulsatile, non-erythematous, palpable mass over the posterior aspect of her left knee that is roughly 3 to 4 cm in diameter and is hypoechoic on ultrasound. Which of the following is associated with this patient's condition?", "answer": "Type IV hypersensitivity", "options": {"A": "Artery aneurysm", "B": "Herniated nucleus pulposus", "C": "Inflammation of the pes anserine bursa", "D": "Type IV hypersensitivity", "E": "Venous valve failure"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "One day after undergoing total knee replacement for advanced degenerative osteoarthritis, a 66-year-old man has progressive lower abdominal pain. The surgery was performed under general anesthesia and the patient was temporarily catheterized for perioperative fluid balance. Several hours after the surgery, the patient began to have decreasing voiding volumes, nausea, and progressive, dull lower abdominal pain. He has Sjögren syndrome. He is sexually active with his wife and one other woman and uses condoms inconsistently. He does not smoke and drinks beer occasionally. Current medications include pilocarpine eye drops. He appears uncomfortable and is diaphoretic. His temperature is 37.3°C (99.1°F), pulse is 90/min, and blood pressure is 130/82 mm Hg. Abdominal examination shows a pelvic mass extending to the umbilicus. It is dull on percussion and diffusely tender to palpation. His hemoglobin concentration is 13.9 g/dL, leukocyte count is 9,000/mm3, a platelet count is 230,000/mm3. An attempt to recatheterize the patient transurethrally is unsuccessful. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Benign prostatic enlargement", "options": {"A": "Benign prostatic enlargement", "B": "Adverse effect of pilocarpine", "C": "Urethral stricture", "D": "Neurogenic bladder", "E": "Prostate cancer\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-day-old male infant presents to the emergency department because his mother states that he has been acting irritable for the past 2 days and has now developed a fever. On exam, the infant appears uncomfortable and has a temperature of 39.1 C. IV access is immediately obtained and a complete blood count and blood cultures are drawn. Lumbar puncture demonstrates an elevated opening pressure, elevated polymorphonuclear neutrophil, elevated protein, and decreased glucose. Ampicillin and cefotaxime are immediately initiated and CSF culture eventually demonstrates infection with a Gram-negative rod. Which of the following properties of this organism was necessary for the infection of this infant?", "answer": "K capsule", "options": {"A": "Fimbriae", "B": "LPS endotoxin", "C": "K capsule", "D": "IgA protease", "E": "M protein"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old primigravida pregnant patient is in her 3rd trimester with twins. She complains of itching and skin lesions. The examination shows vesicular skin lesions on the abdomen but not on the face, palms, or soles. A picture of her abdomen is shown in the image. Her past medical history is insignificant. Her vital signs are all within normal limits. What is the next best step in management?", "answer": "Reassure her and provide symptomatic relief with topical steroids", "options": {"A": "Begin treatment with systemic oral corticosteroids", "B": "Begin weekly antepartum testing to ensure fetal well-being", "C": "Biopsy the lesions to ensure proper diagnosis", "D": "Reassure her and provide symptomatic relief with topical steroids", "E": "Start treatment with an antihistamine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old man is brought to the physician by his daughter because he frequently misplaces his personal belongings and becomes easily confused. His daughter mentions that his symptoms have progressively worsened for the past one year. On mental status examination, he is oriented to person, place, and time. He vividly recalls memories from his childhood but can only recall one of three objects presented to him after 5 minutes. His affect is normal. This patients' symptoms are most likely caused by damage to which of the following?", "answer": "Hippocampus", "options": {"A": "Substantia nigra", "B": "Amygdala", "C": "Ventral posterolateral nucleus", "D": "Hippocampus", "E": "Superior temporal gyrus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old woman comes to the physician because of a 1-year history of pain and stiffness in her fingers and knees. The stiffness lasts for about 10 minutes after she wakes up in the morning. She also reports that her knee pain is worse in the evening. She drinks one glass of wine daily. Her only medication is acetaminophen. She is 175 cm (5 ft 9 in) tall and weighs 102 kg (225 lb); BMI is 33 kg/m2. Physical examination shows firm nodules on the distal interphalangeal joints of the index, ring, and little fingers of both hands. Which of the following is the most likely diagnosis?", "answer": "Osteoarthritis", "options": {"A": "Pseudogout", "B": "Rheumatoid arthritis", "C": "Gout", "D": "Septic arthritis", "E": "Osteoarthritis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old man is brought to the emergency department from a college party because of a 1-hour history of a crawling sensation under his skin. He appears anxious and is markedly pale. His temperature is 38°C (100.4°F), pulse is 104/min, respirations are 18/min, and blood pressure is 145/90 mm Hg. Physical examination shows diaphoretic skin, moist mucous membranes, and dilated pupils. Which of the following substances is most likely the cause of this patient's symptoms?", "answer": "Cocaine", "options": {"A": "Lysergic acid diethylamide", "B": "Phencyclidine", "C": "Cocaine", "D": "Scopolamine", "E": "Oxycodone"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year old woman presents with recurring headaches and pain while combing her hair. Her past medical history is significant for hypertension, glaucoma and chronic deep vein thrombosis in her right leg. Current medication includes rivaroxaban, latanoprost, and benazepril. Her vitals include: blood pressure 130/82 mm Hg, pulse 74/min, respiratory rate 14/min, temperature 36.6℃ (97.9℉). Physical examination reveals neck stiffness and difficulty standing up due to pain in the lower limbs. Strength is 5 out of 5 in the upper and lower extremities bilaterally. Which of the following is the next best step in the management of this patient?", "answer": "Erythrocyte sedimentation rate", "options": {"A": "Lumbar puncture", "B": "CK-MB", "C": "Erythrocyte sedimentation rate", "D": "Temporal artery biopsy", "E": "Fundoscopic examination"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 13-year-old boy with recently diagnosed schizophrenia presents with feelings of anxiety. The patient says that he has been having feelings of dread, especially since a friend of his has been getting bullied at school. He feels troubled by these feeling almost every day and makes it difficult for him to get ready to go to school. He also has been hallucinating worse lately. Past medical history is significant for schizophrenia diagnosed 1 year ago. Current medications are fluphenazine. The patient is afebrile and vital signs are within normal limits. Physical examination is unremarkable. Which of the following medications would most likely be a better course of treatment for this patient?", "answer": "Ziprasidone", "options": {"A": "Chlorpromazine", "B": "Fluoxetine", "C": "Buspirone", "D": "Ziprasidone", "E": "Alprazolam"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 39-year-old woman, gravida 3, para 2, at 32 weeks' gestation comes to the emergency department 1 hour after the sudden onset of severe abdominal pain and nausea. She has had one episode of nonbloody vomiting. Pregnancy has been uncomplicated, except for a blood pressure measurement of 150/90 mm Hg on her last prenatal visit. Her first child was delivered vaginally; her second child was delivered by lower segment transverse cesarean section because of a nonreassuring fetal heart rate. She appears anxious and pale. Her temperature is 36.1°C (96°F), pulse is 115/min, and blood pressure is 92/65 mm Hg. Extremities are cool and clammy. Pelvic examination shows a rigid, tender uterus. The cervix is 30% effaced and 1 cm dilated; the vertex is at -1 station. The fetal heart rate is 100/min. Which of the following is the most likely diagnosis?", "answer": "Abruptio placentae", "options": {"A": "Ruptured uterus", "B": "Ruptured vasa previa", "C": "Abruptio placentae", "D": "Placenta accreta", "E": "Placenta previa"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old professional soccer player presents to the clinic with discomfort and pain while walking. He says that he has an unstable knee joint that started after an injury during a match last week. He adds that he heard a popping sound at the time of the injury. Physical examination of the knee reveals swelling of the knee joint with a positive anterior drawer test. Which of the following structures is most likely damaged in this patient?", "answer": "Anterior cruciate ligament", "options": {"A": "Lateral collateral ligament", "B": "Medial collateral ligament", "C": "Anterior cruciate ligament", "D": "Posterior cruciate ligament", "E": "Ligamentum patellae"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old woman comes to the physician with acute, severe pain in the middle of her lower back. She also complains of constipation and trouble sleeping recently. Menses occur regularly at 28-day intervals. Examination shows localized tenderness to palpation over the lumbar spine. Serum calcium is 14 mg/dL and serum phosphorus is 1.5 mg/dL. An x-ray of the lumbar spine shows a compression fracture of the L4 vertebral body and osteopenia. Which of the following is the most likely underlying cause of this patient's decreased bone mineral density?", "answer": "Increase in interleukin-1 secretion", "options": {"A": "Decrease in ovarian estrogen production", "B": "Increase in calcitonin secretion", "C": "Increase in interleukin-1 secretion", "D": "Decrease in alkaline phosphatase secretion", "E": "Decrease in RANKL receptor expression"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man with a history of hypertension and benign prostate hyperplasia presents for follow-up 4 days into the treatment of a urinary tract infection with trimethoprim-sulfamethoxazole. His symptoms have resolved, and he reports no problems with urination, with the exception of a weak urine stream and hesitancy, which he has had for the past 2 years. At the time of this visit, the patient is afebrile; the blood pressure is 130/88 mm Hg and the heart rate is 80/min. There is no flank tenderness. A urinalysis reveals no leukocytes and is negative for esterase. The urinalysis reveals 2 red blood cells (RBCs)/ high power field (HPF), and there are no casts on urinary sediment analysis. The physician, however, notices the following abnormality:\nPrior treatment\nBUN 12 mg/dL\nCreatinine 1.2 mg/dL\nToday’s visit\nBUN 13 mg/dL\nCreatinine 2.1 mg/dL", "answer": "Reassure the patient, stop trimethoprim-sulfamethoxazole and repeat the measurement in 1–2 weeks", "options": {"A": "Reassure the patient, stop trimethoprim-sulfamethoxazole and repeat the measurement in 1–2 weeks", "B": "Schedule an intravenous pyelography for urinary obstruction", "C": "Schedule a cystoscopy for urethral obstruction", "D": "Admit the patient for further management of acute interstitial nephritis", "E": "Admit the patient for further management of acute tubular necrosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 18-year-old female presents to the clinic complaining of acute abdominal pain for the past couple of hours. The pain is concentrated at the right lower quadrant (RLQ) with no clear precipitating factor and is worse with movement. Acetaminophen seems to help a little but she is concerned as the pain has occurred monthly for the past 3 months. She denies any headache, chest pain, weight changes, diarrhea, nausea/vomiting, fever, or sexual activity. The patient reports a regular menstruation cycle with her last period being 2 weeks ago. A physical examination demonstrates a RLQ that is tender to palpation with a negative psoas sign. A urine beta-hCG test is negative. An ultrasound of the abdomen is unremarkable. What is the main function of the hormone that is primarily responsible for this patient’s symptoms?", "answer": "Increases the activity of cholesterol desmolase to synthesize progesterone", "options": {"A": "Increases the activity of cholesterol desmolase to synthesize progesterone", "B": "Increases the activity of aromatase to synthesize 17-beta-estradiol", "C": "Induction of pulsatile release of follicle stimulating hormone (FSH) and luteinizing hormone (LH)", "D": "Inhibition of the anterior pituitary to decrease secretion of FSH and LH", "E": "Inhibition of the hypothalamus to decrease secretion of gonadotrophin releasing hormone (GnRH)"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 5-year-old boy is brought to the emergency department by his stepmother because of multiple injuries. She says that he sustained these injuries while playing. Radiographic findings show multiple fractures in various stages of healing. Physical examination shows the findings in the image below. What is the most likely diagnosis in this patient?", "answer": "Osteogenesis imperfecta", "options": {"A": "Marfan syndrome", "B": "Wilson disease", "C": "Osteogenesis imperfecta", "D": "Osteochondritis dissecans", "E": "Child abuse"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to the physician by his mother because he does not “listen to her” anymore. The mother also reports that her son cannot concentrate on any tasks lasting longer than just a few minutes. Teachers at his preschool report that the patient is more active compared to other preschoolers, frequently interrupts or bothers other children, and is very forgetful. Last year the patient was expelled from another preschool for hitting his teacher and his classmates when he did not get what he wanted and for being disruptive during classes. He was born at term via vaginal delivery and has been healthy except for 3 episodes of acute otitis media at the age of 2 years. He has met all developmental milestones. His mother has major depressive disorder and his father has Graves' disease. He appears healthy and well nourished. Examination shows that the patient does not seem to listen when spoken to directly. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in treatment?", "answer": "Behavior therapy", "options": {"A": "Behavior therapy", "B": "Methimazole", "C": "Fluoxetine", "D": "Hearing aids", "E": "Methylphenidate"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "At a routine exam, a 68-year-old woman is discovered to have a serum calcium level of 11.5 mg/dL. Follow-up laboratory tests show a high parathyroid hormone with low phosphorus and mildly elevated alkaline phosphatase. 24-hour urine calcium level is elevated. Review of symptoms includes complaints of fatigue, constipation, and diffuse bone pain for which she takes vitamin D. Past medical history is significant for type 2 diabetes mellitus for 25 years and essential hypertension for 15 years. The patient has a history of kidney stones. Family history is irrelevant. Which of the following radiologic findings is consistent with the patient's condition?", "answer": "Subperiosteal bone resorption on hand X-ray", "options": {"A": "Subperiosteal bone resorption on hand X-ray", "B": "Hilar and/or paratracheal adenopathy with bilateral upper lobe lung infiltrates", "C": "Osteopenia, osteolytic lesions and pathological fractures", "D": "Lytic changes in early stage and sclerotic picture in later stage", "E": "Fibronodular opacities in upper lobes of the lung with or without cavitation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 29-year-old woman, gravida 1, para 0, at 36 weeks' gestation is brought to the emergency department after an episode of dizziness and vomiting followed by loss of consciousness lasting 1 minute. She reports that her symptoms started after lying down on her back to rest, as she felt tired during yoga class. Her pregnancy has been uncomplicated. On arrival, she is diaphoretic and pale. Her pulse is 115/min and blood pressure is 90/58 mm Hg. On examination, the patient is lying in the supine position with a fundal height of 36 cm. There is a prolonged fetal heart rate deceleration to 80/min. Which of the following is the most appropriate action to reverse this patient's symptoms in the future?", "answer": "Lying in the left lateral decubitus position", "options": {"A": "Performing the Muller maneuver", "B": "Lying in the supine position and elevating legs", "C": "Gentle compression with an abdominal binder", "D": "Lying in the left lateral decubitus position", "E": "Performing the Valsava maneuver"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man presents to an outpatient clinic for tuberculosis prophylaxis before leaving for a trip to Asia, where tuberculosis is endemic. The Mantoux test is positive, but the chest X-ray and AFB sputum culture are negative. He was started on isoniazid. What is the most likely mechanism of resistance to isoniazid?", "answer": "Mutations in katG", "options": {"A": "Mutations in katG", "B": "Reduction of drug binding to RNA polymerase", "C": "Plasmid-mediated resistance", "D": "Methylation of the RNA binding site", "E": "Increased efflux from the cell"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old man with recently diagnosed testicular cancer visits his oncologist to discuss the treatment plan. His left testicle was removed after a thorough workup of a lump. A pelvic CT showed no enlarged lymph nodes and a simple orchiectomy and pelvic lymph node dissection was completed. The final diagnosis was stage IB non-seminoma testicular cancer (pT2N0Mn/a). A combination of different chemotherapeutic medications is recommended including bleomycin, etoposide, and cisplatin. Each of the antineoplastic drugs has a different mechanism of action; each drug targets cancer cells at a specific phase in the cell cycle and works by inhibiting a major cellular process. Which of the following enzymes would be affected by bleomycin?", "answer": "DNA polymerase β", "options": {"A": "DNA polymerase β", "B": "DNA polymerase III", "C": "Thymidylate synthase", "D": "Ribonucleotide reductase", "E": "Dihydrofolate reductase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old woman presents to the clinic with a 9-month history of seeing bright red blood in the toilet after defecating. Additional complaints include fatigue, shortness of breath, and mild lethargy. She denies the loss of weight, abdominal pain, or changes in dietary behavior. She consumes a balanced diet and takes multiple vitamins every day. The current vital signs include the following: temperature is 37.0°C (98.6°F), pulse rate is 68/min, blood pressure is 130/81 mm Hg, and the respiratory rate is 13/min. On physical examination, you notice increased capillary refill time and pale mucosa. What are the most likely findings for hemoglobin, hematocrit, red blood cell count, and mean corpuscular volume?", "answer": "Hemoglobin: ↓, hematocrit: ↓, red blood cell count: ↓, mean corpuscular volume: ↓", "options": {"A": "Hemoglobin: ↑, hematocrit: ↓, red blood cell count: ↓, mean corpuscular volume: ↑", "B": "Hemoglobin: ↓, hematocrit: ↑, red blood cell count: ↓, mean corpuscular volume: ↓", "C": "Hemoglobin: ↓, hematocrit: ↓, red blood cell count: ↑, mean corpuscular volume: ↑", "D": "Hemoglobin: ↓, hematocrit: ↓, red blood cell count: ↓, mean corpuscular volume: ↓", "E": "Hemoglobin: ↑, hematocrit: ↑, red blood cell count: ↑, mean corpuscular volume: ↑"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 20-year-old woman presents to student health for a 7-day history of sinus congestion. She has also had fever, sore throat, and infectious gastroenteritis. Upon further questioning, she has had similar problems 2 or 3 times a year for as long as she can remember. These have included sinus infections, ear infections, and lung infections. At the clinic, her temperature is 38.6°C (101.4°F), heart rate is 70/min, blood pressure is 126/78 mm Hg, respiratory rate is 18/min, and oxygen saturation is 98% on room air. Physical examination is notable for mucopurulent discharge from both nares and tenderness to palpation over her bilateral maxillae. Sputum gram stain shows gram-positive diplococci. Which of the following best describes the levels of immunoglobulins that would most likely be found upon testing this patient's serum?", "answer": "IgM Level: Normal, IgG Level: Normal, IgA Level: Low", "options": {"A": "IgM Level: Low, IgG Level: Low, IgA Level: Low", "B": "IgM Level: Normal, IgG Level: Low, IgA Level: Low", "C": "IgM Level: Elevated, IgG Level: Low, IgA Level: Low", "D": "IgM Level: Normal, IgG Level: Normal, IgA Level: Low", "E": "IgM Level: Normal, IgG Level: Normal, IgA Level: Normal"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old girl is brought to the physician because menarche has not yet occurred. She has no history of serious illness and takes no medications. She is 162 cm (5 ft 3 in) tall and weighs 80 kg (176 lb); BMI is 31.2 kg/m2. Breast and pubic hair development is Tanner stage 4. She also has oily skin, acne, and hyperpigmentation of the intertriginous areas of her neck and axillae. The remainder of the examination, including pelvic examination, shows no abnormalities. Which of the following is the most likely explanation for this patient's amenorrhea?", "answer": "Elevated LH:FSH ratio", "options": {"A": "XO chromosomal abnormality", "B": "Müllerian agenesis", "C": "Elevated LH:FSH ratio", "D": "Elevated β-hCG levels", "E": "Elevated serum cortisol levels\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 21-year-old man presents to the emergency department with acute back pain. The pain began a few hours prior to presentation and is located on the left lower back. The pain is described to be “shock-like,” 9/10 in pain severity, and radiates to the left groin. His temperature is 98.6°F (37°C), blood pressure is 120/75 mmHg, pulse is 101/min, and respirations are 18/min. The patient appears uncomfortable and is mildly diaphoretic. There is costovertebral angle tenderness and genitourinary exam is unremarkable. A non-contrast computerized tomography (CT) scan of the abdomen and pelvis demonstrates an opaque lesion affecting the left ureter with mild hydronephrosis. Straining of the urine with urine crystal analysis is demonstrated. Which of the following amino acids is most likely poorly reabsorbed by this patient’s kidney?", "answer": "Lysine", "options": {"A": "Aspartic acid", "B": "Histidine", "C": "Isoleucine", "D": "Lysine", "E": "Phenylalanine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old woman, gravida 2, para 1, at 10 weeks' gestation comes to the physician for a prenatal visit. Over the past two weeks, she has felt nauseous in the morning and has had vulvar pruritus and dysuria that started 5 days ago. Her first child was delivered by lower segment transverse cesarean section because of macrosomia from gestational diabetes. Her gestational diabetes resolved after the child was born. She appears well. Ultrasound confirms fetal heart tones and an intrauterine pregnancy. Speculum exam shows a whitish chunky discharge. Her vaginal pH is 4.2. A wet mount is performed and microscopic examination is shown. Which of the following is the most appropriate treatment?", "answer": "Intravaginal clotrimazole", "options": {"A": "Oral metronidazole", "B": "Intravaginal treatment with lactobacillus", "C": "Oral fluconazole", "D": "Topical nystatin", "E": "Intravaginal clotrimazole"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 31-year-old man is brought in to the clinic by his sister because she is concerned about his behavior since the death of their mother 2 months ago. The patient’s sister states that he has always been a ‘loner’ and preferred being by himself than socializing with others. His social isolation resulted in him being ‘socially awkward’, as described by his family. However, 2 months ago, when he found out about the death of their mother, he showed little emotion and attended her funeral in jeans and a dirty T-shirt which upset the rest of their family. When asked about it, he shrugged and said he was in a hurry to get to the funeral and “just left the house with what I had on.” He does not speak much during the interview, allowing his sister to speak on his behalf. His sister insists that he has ‘always been like this’, quiet and a complacent child who had no interest in playing with other children. The patient currently lives alone and spends his time repairing and building electrical appliances, and his sister is worried that his self-imposed isolation is making it ‘impossible for him to interact with other people normally’. Which of the following is the most likely diagnosis in this patient?\n ", "answer": "Schizoid personality disorder", "options": {"A": "Schizoid personality disorder", "B": "Schizophrenia", "C": "Social anxiety disorder", "D": "Depressive disorder", "E": "Asperger’s syndrome"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A male newborn is born at 37 weeks' gestation after spontaneous vaginal delivery. The mother had no prenatal care. Physical examination shows a urethral opening on the dorsal aspect of the penis, 4 mm proximal to the glans. There is a 3-cm defect in the midline abdominal wall superior to the pubic symphysis with exposure of moist, erythematous mucosa. Which of the following is the most likely underlying cause of this patient's findings?", "answer": "Malpositioning of the genital tubercle", "options": {"A": "Persistence of the urogenital membrane", "B": "Incomplete union of the labioscrotal swellings", "C": "Malpositioning of the genital tubercle", "D": "Abnormal development of the gubernaculum", "E": "Failed fusion of the urethral folds"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 37-year-old obese woman presents to the neurology clinic complaining of severe pain in her left wrist and tingling sensation in her left thumb, index finger, and middle finger, and some part of her ring finger. The pain started as an occasional throb and she could ignore it or takes analgesics but now the pain is much worse and wakes her up at night. She is also concerned that these fingers are occasionally numb and sometimes tingle. She works as a typist and her pain mostly increases after typing all day. Her right wrist and fingers are fine. Nerve conduction studies reveal nerve compression. Which of the following additional clinical findings would most likely be present in this patient?", "answer": "Inability to oppose thumb to other digits", "options": {"A": "Inability to oppose thumb to other digits", "B": "Flattened hypothenar eminence", "C": "Inability to adduct the little finger", "D": "Atrophied adductor pollicis muscle", "E": "Paresthesia over the thenar eminence"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An otherwise healthy 45-year-old man comes to the physician because of a painful ulcer on his tongue for 3 days. Examination shows a shallow, tender 5-mm wide ulcer on the lateral aspect of the tongue, adjacent to his left first molar. There is no induration surrounding the ulcer or cervical lymphadenopathy. A lesion of the cranial nerve responsible for the transmission of pain from this ulcer would most likely result in which of the following?", "answer": "Difficulty chewing", "options": {"A": "Decreased sensation in the upper lip", "B": "Difficulty chewing", "C": "Loss of taste from the supraglottic region", "D": "Inability to wrinkle the forehead", "E": "Lateral deviation of the tongue"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 60-year-old man has had intermittent pain in his right great toe for the past 2 years. Joint aspiration and crystal analysis shows thin, tapered, needle shaped intracellular crystals that are strongly negatively birefringent. Radiograph demonstrates joint space narrowing of the 1st metatarsophalangeal (MTP) joint with medial soft tissue swelling. What is the most likely cause of this condition?", "answer": "Monosodium urate crystal deposition", "options": {"A": "Monosodium urate crystal deposition", "B": "Calcium pyrophosphate deposition", "C": "Uric acid crystal deposition", "D": "Tuberculosis", "E": "Rheumatoid arthritis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 53-year-old man comes to the physician because of a 3-month history of a nonpruritic rash, fatigue, and decreased urination. Physical examination shows multiple erythematous, purpuric papules on his trunk and extremities that do not blanch when pressed. Serum creatinine is elevated and urinalysis shows red blood cell casts and protein. Serum complement levels are decreased. Renal biopsy shows subendothelial immune complex deposits with granular immunofluorescence and tram-track basement membrane splitting. Further laboratory evaluation of this patient is most likely to show the presence of which of the following antibodies?", "answer": "Anti-hepatitis C antibodies", "options": {"A": "Anti-desmoglein antibodies", "B": "Anti-hepatitis C antibodies", "C": "Anti-DNA topoisomerase antibodies", "D": "Antineutrophil cytoplasmic antibodies", "E": "Anticardiolipin antibodies"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 75-year-old woman presents to the physician with a complaint of a frequent need to void at nighttime, which has been disrupting her sleep. She notes embarrassingly that she is often unable to reach the bathroom in time, and experiences urinary leakage throughout the night as well as during the day. The patient undergoes urodynamic testing and a urinalysis is obtained which is normal. She is instructed by the physician to perform behavioral training to improve her bladder control. Which of the following is the most likely diagnosis contributing to this patient’s symptoms?", "answer": "Urge incontinence", "options": {"A": "Overflow incontinence", "B": "Stress incontinence", "C": "Total incontinence", "D": "Urge incontinence", "E": "Urinary tract infection"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A researcher is investigating whether there is an association between the use of social media in teenagers and bipolar disorder. In order to study this potential relationship, she collects data from people who have bipolar disorder and matched controls without the disorder. She then asks how much on average these individuals used social media in the 3 years prior to their diagnosis. This continuous data is divided into 2 groups: those who used more than 2 hours per day and those who used less than 2 hours per day. She finds that out of 1000 subjects, 500 had bipolar disorder of which 300 used social media more than 2 hours per day. She also finds that 400 subjects who did not have the disorder also did not use social media more than 2 hours per day. Which of the following is the odds ratio for development of bipolar disorder after being exposed to more social media?", "answer": "6", "options": {"A": "0.17", "B": "0.67", "C": "1.5", "D": "2.25", "E": "6"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old female presents to her primary care physician because of chronic fatigue that has stopped her from gardening and walking with her friends. Upon further questioning, she elaborates that she feels fine after waking up but gradually becomes more tired and weak as the day progresses. This appears to be particularly problematic when she is engaged in physical activity or when eating. Review of systems elicits that she occasionally experiences double vision after spending a prolonged period looking at a computer screen. Testing confirms the diagnosis and the patient is prescribed a long-acting medication to alleviate her symptoms. The products of the enzyme that is inhibited by the prescribed drug are transported by a protein that is sensitive to which of the following chemicals?", "answer": "Hemicholinium", "options": {"A": "Botulinum", "B": "Guanethidine", "C": "Hemicholinium", "D": "Reserpine", "E": "Vesamicol"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3-day-old newborn is brought to the physician because of abdominal distention, inconsolable crying, and 3 episodes of bilious vomiting since the previous evening. He was delivered at home at 40 weeks' gestation by a trained midwife. He has not passed meconium. Physical examination shows abdominal distention, a tight anal sphincter, and an explosive passage of air and feces on removal of the examining finger. Abnormal development of which of the following best explains this patient's condition?", "answer": "Submucosa and muscularis externa", "options": {"A": "Muscularis mucosae and serosa", "B": "Epithelium and lamina propria", "C": "Submucosa and muscularis externa", "D": "Epithelium and submucosa", "E": "Muscularis mucosae and lamina propria"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Two days after undergoing porcine aortic valve replacement surgery for aortic valve stenosis, a 62-year-old patient develops yellow discoloration of the sclera. His vital signs are within normal limits. Physical examination shows scleral icterus. Abdominal examination shows no abnormalities. Laboratory studies show:\nHematocrit 49%\nReticulocyte count 1.2%\nSerum\nAST 15 U/L\nALT 18 U/L\nBilirubin, total 2.8 mg/dL\nDirect 0.3 mg/dL\nLactate dehydrogenase 62 U/L\nWhich of the following is the most likely underlying mechanism of this patient's laboratory findings?\"", "answer": "Impaired bilirubin conjugation", "options": {"A": "Impaired bilirubin conjugation", "B": "Mechanical erythrocyte damage", "C": "Drug-induced toxicity", "D": "Absent hepatic glucuronosyltransferase", "E": "Impaired bilirubin excretion"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 59-year-old woman comes to the emergency department because of a 2-day history of worsening fever, chills, malaise, productive cough, and difficulty breathing. Three days ago, she returned from a trip to South Africa. She has type 2 diabetes mellitus, hypertension, and varicose veins. Her current medications include metformin, lisinopril, and atorvastatin. Her temperature is 39.4°C (102.9°F), pulse is 102/minute, blood pressure is 94/68 mm Hg, and respirations are 31/minute. Pulse oximetry on 2 L of oxygen via nasal cannula shows an oxygen saturation of 91%. Examination reveals decreased breath sounds and dull percussion over the left lung base. The skin is very warm and well-perfused. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11.6 g/dL\nLeukocyte count 15,400/mm3\nplatelet count 282,000/mm3\nSerum\nNa+ 144 mEq/L\nCl- 104 mEq/L\nK+ 4.9 mEq/L\nCreatinine 1.5 mg/dL\nBlood and urine for cultures are obtained. Intravenous fluid resuscitation is begun. Which of the following is the next best step in management?\"", "answer": "Intravenous vancomycin and ceftriaxone", "options": {"A": "Intravenous ceftriaxone and azithromycin", "B": "Erythromycin", "C": "External cooling and intravenous acetaminophen", "D": "Intravenous vancomycin and ceftriaxone", "E": "CT of the chest with contrast"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old woman, gravida 1, para 0, at 30 weeks' gestation is brought to the emergency department because of progressive upper abdominal pain for the past hour. The patient vomited once on her way to the hospital. She said she initially had dull, generalized stomach pain about 6 hours prior, but now the pain is located in the upper abdomen and is more severe. There is no personal or family history of any serious illnesses. She is sexually active with her husband. She does not smoke or drink alcohol. Medications include folic acid and a multivitamin. Her temperature is 38.5°C (101.3°F), pulse is 100/min, and blood pressure is 130/80 mm Hg. Physical examination shows right upper quadrant tenderness. The remainder of the examination shows no abnormalities. Laboratory studies show a leukocyte count of 12,000/mm3. Urinalysis shows mild pyuria. Which of the following is the most appropriate definitive treatment in the management of this patient?", "answer": "Appendectomy", "options": {"A": "Appendectomy", "B": "Cefoxitin and azithromycin", "C": "Biliary drainage", "D": "Intramuscular ceftriaxone followed by cephalexin", "E": "Laparoscopic removal of ovarian cysts"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old male with a 1-year history of bilateral knee arthritis presents with epigastric pain that intensifies with meals. He has been self-medicating with aspirin, taking up to 2,000 mg per day for the past six months. Which of the following medications, if taken instead of aspirin, could have minimized his risk of experiencing this epigastric pain?", "answer": "Celecoxib", "options": {"A": "Ketorolac", "B": "Indomethacin", "C": "Naproxen", "D": "Ibuprofen", "E": "Celecoxib"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman comes to the physician because of a 2-day history of intermittent dark urine and mild flank pain. She has also had a cough, sore throat, and runny nose for the past 5 days. She has not had dysuria. She takes no medications. She has no known allergies. Her temperature is 37°C (98.6°F). Examination of the back shows no costovertebral angle tenderness. Laboratory studies show:\nHemoglobin 10.4 g/dL\nLeukocyte count 8,000/mm3\nPlatelet count 200,000/mm3\nSerum\nNa+ 135 mEq/L\nK+ 4.9 mEq/L\nCl- 101 mEq/L\nHCO3- 22 mEq/L\nUrea nitrogen 18 mg/dL\nCreatinine 1.1 mg/dL\nUrine\nColor yellow\nBlood 3+\nProtein 1+\nLeukocyte esterase negative\nAn ultrasound of the kidney and bladder shows no abnormalities. Which of the following is the most likely cause of this patient's symptoms?\"", "answer": "Renal glomerular damage", "options": {"A": "Interstitial renal inflammation", "B": "Renal papillary necrosis", "C": "Renal glomerular damage", "D": "Ischemic tubular injury", "E": "Urothelial neoplasia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A study is being conducted on depression using the Patient Health questionnaire (PHQ-9) survey data embedded within a popular social media network with a response size of 500,000 participants. The sample population of this study is approximately normal. The mean PHQ-9 score is 14, and the standard deviation is 4. How many participants have scores greater than 22?", "answer": "12,500", "options": {"A": "12,500", "B": "17,500", "C": "25,000", "D": "160,000", "E": "175,000"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 77-year-old woman is brought to the physician for gradually increasing confusion and difficulty walking for the past 4 months. Her daughter is concerned because she has been forgetful and seems to be walking more slowly. She has been distracted during her weekly bridge games and her usual television shows. She has also had increasingly frequent episodes of urinary incontinence and now wears an adult diaper daily. She has hyperlipidemia and hypertension. Current medications include lisinopril and atorvastatin. Her temperature is 36.8°C (98.2°F), pulse is 84/min, respirations are 15/min, and blood pressure is 139/83 mmHg. She is confused and oriented only to person and place. She recalls 2 out of 3 words immediately and 1 out of 3 after five minutes. She has a broad-based gait and takes short steps. Sensation is intact and muscle strength is 5/5 throughout. Laboratory studies are within normal limits. Which of the following is the most likely diagnosis in this patient?", "answer": "Normal pressure hydrocephalus", "options": {"A": "Dementia with Lewy-bodies", "B": "Pseudodementia", "C": "Frontotemporal dementia", "D": "Normal pressure hydrocephalus", "E": "Creutzfeldt-Jakob disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 1-year-old boy is brought to the physician for the evaluation of swelling around the eyelids. He was born at term after an uncomplicated pregnancy. He is at the 95th percentile for weight and 60th percentile for length. His blood pressure is 130/86 mm Hg. Physical examination shows an empty scrotal sac and a left-sided abdominal mass. Ophthalmologic examination shows no abnormalities. Urinalysis shows a proteinuria of 3+ and fatty casts. Abdominal ultrasound shows a hypervascular mass at the upper pole of the kidney. Which of the following best describes the pathogenesis of this patient's disease?", "answer": "Loss of function of zinc finger transcription factor", "options": {"A": "Inhibition of hypoxia-inducible factor 1a", "B": "Deficiency of 17α-hydroxylase", "C": "Increased expression of insulin-like growth factor 2", "D": "Deletion of the WT1 gene on chromosome 11", "E": "Loss of function of zinc finger transcription factor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old female presents to her primary care physician complaining of right upper quadrant pain over the last 6 months. Pain is worst after eating and feels like intermittent squeezing. She also admits to lighter colored stools and a feeling of itchiness on her skin. Physical exam demonstrates a positive Murphy's sign. The vitamin level least likely to be affected by this condition is associated with which of the following deficiency syndromes?", "answer": "Scurvy", "options": {"A": "Night blindness", "B": "Scurvy", "C": "Rickets and osteomalacia", "D": "Hemolytic anemia", "E": "Increased prothrombin time and easy bleeding"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "On morning labs, a patient's potassium comes back at 5.9 mEq/L. The attending thinks that this result is spurious, and asks the team to repeat the electrolytes. Inadvertently, the medical student, intern, and resident all repeat the electrolytes that same morning. The following values are reported: 4.3 mEq/L, 4.2 mEq/L, and 4.2 mEq/L. What is the median potassium value for that patient that day including the first value?", "answer": "4.25 mEq/L", "options": {"A": "4.2 mEq/L", "B": "4.25 mEq/L", "C": "4.3 mEq/L", "D": "4.65 mEq/L", "E": "1.7 mEq/L"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old woman presents to a medical office for a follow-up evaluation. The medical history is significant for type 1 diabetes, for which she takes insulin. She was recently hospitalized for diabetic ketoacidosis following a respiratory infection. Today she brings in a list of her most recent early morning fasting blood glucose readings for review. Her glucose readings range from 126 mg/dL–134 mg/dL, except for 2 readings of 350 mg/dL and 380 mg/dL, taken at the onset of her recent hospitalization. Given this data set, which measure(s) of central tendency would be most likely affected by these additional extreme values?", "answer": "Mean", "options": {"A": "Mean", "B": "Median", "C": "Mode", "D": "Mean and median", "E": "Median and mode"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman comes to the physician because of a 6-week history of fatigue and weakness. Examination shows marked pallor of the conjunctivae. The spleen tip is palpated 2 cm below the left costal margin. Her hemoglobin concentration is 9.5 g/dL, serum lactate dehydrogenase concentration is 750 IU/L, and her serum haptoglobin is undetectable. A peripheral blood smear shows multiple spherocytes. When anti-IgG antibodies are added to a sample of the patient's blood, there is clumping of the red blood cells. Which of the following is the most likely predisposing factor for this patient's condition?", "answer": "Systemic lupus erythematosus", "options": {"A": "Hereditary spectrin defect", "B": "Bicuspid aortic valve", "C": "Epstein-Barr virus infection", "D": "Mycoplasma pneumoniae infection", "E": "Systemic lupus erythematosus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 4-month-old girl is seen for ongoing lethargy and vomiting. She was born to a 31-year-old G2P2 mother with a history of hypertension. She has had 7 episodes of non-bloody, non-bilious vomiting and 3 wet diapers over the last 24 hours. Laboratory results are shown below.\n\nSerum:\nNa+: 132 mEq/L\nCl-: 100 mEq/L\nK+: 3.2 mEq/L\nHCO3-: 27 mEq/L\nBUN: 13 mg/dL\nGlucose: 30 mg/dL\nLactate: 2 mmol/L\nUrine ketones: < 20 mg/dL\n\nWhich of the following is the most likely diagnosis?", "answer": "Medium chain acyl-CoA dehydrogenase deficiency", "options": {"A": "Glucose-6-phosphatase deficiency", "B": "Glucocerebrosidase deficiency", "C": "Sphingomyelinase deficiency", "D": "Medium chain acyl-CoA dehydrogenase deficiency", "E": "Galactose-1-phosphate uridyltransferase deficiency"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 6-month-old boy is brought to the emergency department because of irritability and poor feeding for 6 days. He has also not had a bowel movement in 9 days and has been crying less than usual. He is bottle fed with formula and his mother has been weaning him with mashed bananas mixed with honey for the past 3 weeks. His immunizations are up-to-date. He appears weak and lethargic. He is at the 50th percentile for length and 75th percentile for weight. Vital signs are within normal limits. Examination shows dry mucous membranes and delayed skin turgor. There is poor muscle tone and weak head control. Neurological examination shows ptosis of the right eye. Which of the following is the most appropriate initial treatment?", "answer": "Human-derived immune globulin", "options": {"A": "Human-derived immune globulin", "B": "Intravenous gentamicin", "C": "Equine-derived antitoxin", "D": "Plasmapheresis", "E": "Pyridostigmine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 68-year-old man comes to the emergency department 12 hours after the appearance of tender, purple discolorations on his thighs and lower abdomen. He began taking a medication 4 days ago after failed cardioversion for atrial fibrillation, but he cannot remember the name. Physical examination shows a tender bluish-black discoloration on the anterior abdominal wall. A photograph of the right thigh is shown. Which of the following is the most likely explanation for this patient's skin findings?", "answer": "Reduced levels of protein C", "options": {"A": "Deficiency of vitamin K", "B": "Decreased synthesis of antithrombin III", "C": "Antibodies against platelet factor 4", "D": "Increased levels of protein S", "E": "Reduced levels of protein C"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 8-year-old girl is brought to the physician for a well-child examination. Since the age of 2 years, she has had multiple fractures after minor trauma. During the past year, she has fractured the left humerus and right clavicle after falls. Her father also has a history of recurrent fractures. She is at the 5th percentile for height and 20th percentile for weight. Vital signs are within normal limits. Physical examination shows increased convexity of the thoracic spine. Forward bend test demonstrates asymmetry of the thoracolumbar region. There is a curvature of the tibias bilaterally, and the left leg is 2 cm longer than the right. There is increased mobility of the joints of the upper and lower extremities. Which of the following is the most likely additional finding?", "answer": "Hearing impairment", "options": {"A": "Dislocated lens", "B": "Hearing impairment", "C": "Widely spaced permanent teeth", "D": "Cerebral berry aneurysm", "E": "Increased head circumference"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 59-year-old healthy woman presents to her primary care physician’s office six weeks after undergoing an elective breast augmentation procedure in the Dominican Republic. She was told by her surgeon to establish post-operative care once back in the United States. Today she is bothered by nausea and early satiety. Her past medical history is significant only for GERD for which she takes ranitidine. Since the surgery, she has also taken an unknown opioid pain medication that was given to her by the surgeon. She reports that she has been taking approximately ten pills a day. On examination she is afebrile with normal vital signs and her surgical incisions are healing well. Her abdomen is distended and tympanitic. The patient refuses to stop her pain medicine and laxatives are not effective; what medication could be prescribed to ameliorate her gastrointestinal symptoms?", "answer": "Naloxegol", "options": {"A": "Metoclopramide", "B": "Pantoprazole", "C": "Senna", "D": "Naloxegol", "E": "Naproxen"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old man presents to his primary care provider reporting weakness. He recently noticed that he has difficulty letting go of a doorknob or releasing his hand after shaking hands with others. His past medical history is notable for diabetes, for which he takes metformin. He drinks 2-3 beers per day, uses marijuana occasionally, and works as a security guard. His family history is notable for an early cardiac death in his father. His temperature is 98.6°F (37°C), blood pressure is 130/85 mmHg, pulse is 85/min, and respirations are 18/min. On exam, there is notable muscle atrophy in his hands, feet, and neck. He has delayed hand grip release bilaterally and is slow to return from a smile to a neutral facial expression. His gait is normal, and Romberg's test is negative. He also has frontal balding. This patient’s condition is caused by a mutation in which of the following genes?", "answer": "DMPK", "options": {"A": "DMPK", "B": "DPC", "C": "Dystrophin", "D": "Frataxin", "E": "SMN1"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 71-year-old man presents to the emergency department for shortness of breath. The patient was returning from a business trip to China, when he suddenly felt short of breath during the taxi ride home from the airport. The patient has a past medical history of poorly controlled diabetes mellitus and a 50 pack-year smoking history. The patient is non-compliant with his medications and is currently only taking ibuprofen. An initial ECG demonstrates sinus tachycardia. A chest radiograph is within normal limits. Laboratory values are notable for a creatinine of 2.4 mg/dL and a BUN of 32 mg/dL as compared to his baseline creatinine of 0.9 mg/dL. His temperature is 98.8°F (37.1°C), pulse is 122/min, blood pressure is 145/90 mmHg, respirations are 19/min, and oxygen saturation is 93% on room air. On physical exam, you note an older gentleman in distress. Cardiac exam is notable only for tachycardia. Pulmonary exam is notable for expiratory wheezes. Which of the following is the best confirmatory test for this patient?", "answer": "Ventilation perfusion scan", "options": {"A": "Arterial blood gas", "B": "CT angiogram", "C": "D-dimer", "D": "Lower extremity ultrasound with Doppler", "E": "Ventilation perfusion scan"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-week-old boy presents to the emergency department because of unusual irritability and lethargy. The patient is admitted to the pediatric intensive care unit and minutes later develops metabolic encephalopathy. This progressed to a coma, followed by death before any laboratory tests are completed. The infant was born at home via vaginal delivery at 39 weeks' of gestation. His mother says that the symptoms started since the infant was 4-days-old, but since he only seemed ‘tired’, she decided not to seek medical attention. Further testing during autopsy shows hyperammonemia, low citrulline, and increased orotic acid. Which of the following enzymes is most likely deficient in this patient?", "answer": "Ornithine transcarbamylase", "options": {"A": "Branched-chain alpha-ketoacid dehydrogenase", "B": "Cystathionine synthase deficiency", "C": "Homogentisic acid dioxygenase", "D": "Ornithine transcarbamylase", "E": "Propionyl-CoA carboxylase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old woman, gravida 2, para 1, at 30 weeks' gestation comes to the emergency department because of severe right-sided back pain for the last hour. The pain is colicky and radiates to the right groin. The patient also reports nausea and pain with urination. Pregnancy has been uncomplicated and the patient reports that she has been following up with her gynecologist on a regular basis. There is no personal or family history of serious illness. She does not smoke or drink alcohol. Medications include folic acid and a multivitamin. Temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 130/80 mm Hg. Examination of the back shows costovertebral angle tenderness on the right side. Laboratory studies show:\nUrine\nProtein negative\nRBC casts negative\nRBC 5–7/hpf\nWBC casts negative\nWBC 1–2/hpf\nWhich of the following is the most likely diagnosis?\"", "answer": "Nephrolithiasis", "options": {"A": "Cholecystitis", "B": "Nephrolithiasis", "C": "Pelvic inflammatory disease", "D": "Pyelonephritis", "E": "Appendicitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 18-year-old man is brought to the emergency department after his mother found him locked in his room stammering about a government conspiracy to brainwash him in subterranean tunnels. His mother says that he has never done this before, but 6 months ago he stopped going to classes and was subsequently suspended from college. She reports that he has become increasingly taciturn over the course of the past month. He drinks one to two beers daily and has smoked one pack of cigarettes daily for 3 years. He occasionally smokes marijuana. His father was diagnosed with schizophrenia at the age of 25 years. The patient has had no friends or social contacts other than his mother since he was suspended. He appears unkempt and aloof. On mental status examination, he is disorganized and shows poverty of speech. He says his mood is “good.” He does not hear voices and has no visual or tactile hallucinations. Toxicology screening is negative. Which of the following is a favorable prognostic factor for this patient's condition?", "answer": "Acute onset of symptoms", "options": {"A": "Predominance of negative symptoms", "B": "Acute onset of symptoms", "C": "Lack of social support", "D": "Male sex", "E": "Cannabis use"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator studying patients with symptoms of arthritis detects a nonenveloped virus with a single-stranded DNA genome in the serum of a pregnant patient. Fetal infection with this pathogen is most likely to cause which of the following manifestations?", "answer": "Hydrops fetalis", "options": {"A": "Hydrops fetalis", "B": "Chorioretinitis", "C": "Microcephaly", "D": "Notched teeth", "E": "Vesicular rash"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old man comes to the Veterans Affairs hospital because of difficulty sleeping for the past 9 weeks. He is a soldier who returned from a deployment in Afghanistan 12 weeks ago. Fifteen weeks ago, his unit was ambushed in a deserted street, and a fellow soldier was killed. He wakes up frequently during the night from vivid dreams of this incident. He blames himself for being unable to save his friend. He also has trouble falling asleep and gets up earlier than desired. During this period, he has started to avoid walking in deserted streets. Vital signs are within normal limits. Physical examination shows no abnormalities. He refuses cognitive behavioral therapy and is started on sertraline. Five weeks later, he returns to the physician and complains about persistent nightmares and difficulty sleeping. Which of the following is the most appropriate next step in management?", "answer": "Prazosin therapy", "options": {"A": "Diazepam therapy", "B": "Triazolam therapy", "C": "Phenelzine therapy", "D": "Prazosin therapy", "E": "Supportive psychotherapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old woman is brought into the emergency department at 5 AM because of chest pain that woke her up at 3 AM. The pain is constant and has not decreased in intensity during this time. She has no history of any similar episodes. She has systemic lupus erythematosus without major organ involvement. She takes prednisone, calcium, alendronate, and hydroxychloroquine. The blood pressure is 120/75 mm Hg, pulse is 85/min, respirations are 19/min, and the temperature is 36.5°C (97.7°F). An examination of the chest including the heart and lungs shows no abnormalities. The electrocardiogram (ECG) shows no abnormalities. Computed tomography (CT) scan of the chest shows esophageal thickening near the mid-portion. Which of the following is the most likely diagnosis?", "answer": "Pill esophagitis", "options": {"A": "Diffuse esophageal spasm", "B": "Esophageal perforation", "C": "Esophageal stricture", "D": "Gastroesophageal reflux disease", "E": "Pill esophagitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Six hours after near-total thyroidectomy for Graves disease, a 58-year-old man has not had any urine output. The surgery was successful and the patient feels well except for slight neck pain. He has type 2 diabetes mellitus and hypertension. His father had autosomal dominant polycystic kidney disease. Prior to the surgery, the patient was taking metformin and lisinopril regularly and ibuprofen as needed for headaches. His current medications include acetaminophen and codeine. His temperature is 36.2°C (97.2°F), pulse is 82/min, and blood pressure is 122/66 mm Hg. Physical examination shows a 7-cm surgical wound on the anterior neck with mild swelling, but no reddening or warmth. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Perform bedside bladder scan", "options": {"A": "Obtain renal scintigraphy", "B": "Obtain urinalysis", "C": "Perform bedside bladder scan", "D": "Obtain renal biopsy", "E": "Administer furosemide\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old man presents to his primary care physician because of abdominal pain. He has had this pain intermittently for several years but feels that it has gotten worse after he started a low carbohydrate diet. He says that the pain is most prominent in the epigastric region and is also associated with constipation and foul smelling stools that float in the toilet bowl. He has a 15-year history of severe alcoholism but quit drinking 1 year ago. Laboratory studies are obtained showing a normal serum amylase and lipase. Both serum and urine toxicology are negative. His physician starts him on appropriate therapy and checks to make sure that his vitamin and mineral levels are appropriate. Which of the following deficiency syndromes is most closely associated with the cause of this patient's abdominal pain?", "answer": "Osteomalacia", "options": {"A": "Cheilosis and corneal vascularization", "B": "Encephalopathy, ophthalmoplegia, and gait ataxia", "C": "Microcytic anemia", "D": "Megaloblastic anemia without neurologic changes", "E": "Osteomalacia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 67-year-old man comes to the physician because of a 6-month history of increasing shortness of breath on exertion, dry cough, and fatigue. He has not had any fevers or night sweats. He worked in a glass manufacturing factory for 15 years and retired 2 years ago. Pulmonary examination shows diffuse crackles bilaterally. An x-ray of the chest shows well-defined calcification of the rims of hilar lymph nodes and scattered nodules in both upper lung fields. This patient is most likely to develop which of the following complications?", "answer": "Pulmonary tuberculosis", "options": {"A": "Malignant mesothelioma", "B": "Invasive aspergillosis", "C": "Pneumocystis pneumonia", "D": "Spontaneous pneumothorax", "E": "Pulmonary tuberculosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old woman comes to the physician because of fatigue, difficulty falling asleep, and night sweats for the past 6 months. Over the past year, her menstrual cycle has become irregular and her last menstrual period was 2 months ago. She quit smoking 2 years ago. Pelvic exam shows vulvovaginal atrophy. A pregnancy test is negative. Which of the following changes is most likely to occur in this patient's condition?", "answer": "Increased follicle-stimulating hormone", "options": {"A": "Decreased luteinizing hormone", "B": "Increased estrogen", "C": "Increased inhibin B", "D": "Decreased gonadotropin-releasing hormone", "E": "Increased follicle-stimulating hormone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 41-year-old woman presents with back pain for the past 2 days. She says that the pain radiates down along the posterior right thigh and leg. She says the pain started suddenly after lifting a heavy box 2 days ago. Past medical history is irrelevant. Physical examination reveals a straight leg raise (SLR) test restricted to 30°, inability to walk on her toes, decreased sensation along the lateral border of her right foot, and diminished ankle jerk on the same side. Which of the following nerve roots is most likely compressed?", "answer": "First sacral nerve root (S1)", "options": {"A": "Fifth lumbar nerve root (L5)", "B": "First sacral nerve root (S1)", "C": "Third sacral nerve root (S3)", "D": "Fourth lumbar nerve root (L4)", "E": "Second sacral nerve root (S2)"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old woman comes to the physician because of a 3-day history of redness and swelling of her right leg and fever. She says the leg is very painful and the redness over it has become larger. She appears ill. Her temperature is 39.3°C (102.7°F), pulse is 103/min, and blood pressure is 138/90 mm Hg. Cardiopulmonary examination shows no abnormalities. Examination shows an area of diffuse erythema and swelling over her anterior right lower leg; it is warm and tender to touch. Squeezing of the calf does not elicit tenderness. There is swelling of the right inguinal lymph nodes. Pedal pulses are palpable bilaterally. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Tinea pedis\n\"", "options": {"A": "Rheumatoid arthritis", "B": "Graves disease", "C": "Cigarette smoking", "D": "Immobility", "E": "Tinea pedis\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 35-year-old female presents to the emergency room complaining of diarrhea and dehydration. She has been experiencing severe watery diarrhea for the past 3 days. She reports that she has been unable to leave the bathroom for more than a few minutes at a time. She noticed earlier today that there was some blood on her toilet paper after wiping. She recently returned from a volunteer trip to Yemen where she worked at an orphanage. Her past medical history is notable for psoriasis for which she takes sulfasalazine. The patient drinks socially and does not smoke. Her temperature is 99°F (37.2°C), blood pressure is 100/55 mmHg, pulse is 130/min, and respirations are 20/min. Mucus membranes are dry. Her eyes appear sunken. Capillary refill is 4 seconds. The patient is started on intravenous fluid resuscitation. Which of the following processes is capable of transmitting the genetic material for the toxin responsible for this patient’s condition?", "answer": "Transduction", "options": {"A": "Endospore formation", "B": "Transformation", "C": "Conjugation", "D": "Transduction", "E": "Transposition"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old toddler was rushed to the emergency department after consuming peanut butter crackers at daycare. The daycare staff report that the patient has a severe allergy to peanut butter and he was offered the crackers by mistake. The patient is in acute distress. The vital signs include: blood pressure 60/40 mm Hg and heart rate 110/min. There is audible inspiratory stridor and the respiratory rate is 27/min. Upon examination, his chest is covered in a maculopapular rash. Intubation is attempted and failed due to extensive laryngeal edema. The decision for cricothyrotomy is made. Which of the following is the most likely mechanism of this pathology?", "answer": "Release of IL-4", "options": {"A": "C5a production", "B": "Release of IL-4", "C": "Deposition of antigen-antibody complexes", "D": "IL-2 secretion", "E": "C3b interaction"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old G2P0 presents at 37 weeks gestation with a watery vaginal discharge. The antepartum course was remarkable for an abnormal ultrasound finding at 20 weeks gestation. The vital signs are as follows: blood pressure, 110/80 mm Hg; heart rate, 91/min; respiratory rate, 13/min; and temperature, 36.4℃ (97.5℉). The fetal heart rate is 141/min. On speculum examination, there were no vaginal or cervical lesions, but there is a continuous watery vaginal discharge with traces of blood. The discharge is fern- and nitrite-positive. Soon after the initial examination, the bleeding increases. Fetal monitoring shows a heart rate of 103/min with late decelerations. Which of the following ultrasound findings was most likely present in the patient and predisposed her to the developed condition?", "answer": "Velamentous cord insertion", "options": {"A": "Loss of the normal retroplacental hyperechogenic region", "B": "Velamentous cord insertion", "C": "Retroplacental hematoma", "D": "Subchorionic cyst", "E": "Placental edge-internal os distance of 3 cm"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An experimental drug, ES 62, is being studied. It prohibits the growth of vancomycin-resistant Staphylococcus aureus. It is highly lipid-soluble. The experimental design is dependent on a certain plasma concentration of the drug. The target plasma concentration is 100 mmol/dL. Which of the following factors is most important for calculating the appropriate loading dose? ", "answer": "Volume of distribution", "options": {"A": "Rate of administration", "B": "Clearance of the drug", "C": "Half-life of the drug", "D": "Therapeutic index", "E": "Volume of distribution"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old male graduate student comes to the physician for a two-month history of repeated thoughts and anxiety that he is going to be harmed by someone on the street. The anxiety worsened after witnessing a pedestrian getting hit by a car two weeks ago. He says, “That was a warning sign.” On his way to school, he now often leaves an hour earlier to take a detour and hide from people that he thinks might hurt him. He is burdened by his coursework and fears that his professors are meaning to fail him. He says his friends are concerned about him but that they do not understand because they were not present at the accident. The patient has no known history of psychiatric illness. On mental status exam, he is alert and oriented, and shows full range of affect. Thought processes and speech are organized. His memory and attention are within normal limits. He denies auditory, visual, or tactile hallucinations. Urine toxicology screening is negative. Which of the following is the most likely diagnosis in this patient?", "answer": "Delusional disorder", "options": {"A": "Avoidant personality disorder", "B": "Schizotypal personality disorder", "C": "Delusional disorder", "D": "Generalized anxiety disorder", "E": "Schizoid personality disorder"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old male presents to the clinic for a follow-up visit. He takes metformin every day and says that he is compliant with his medication but can not control his diet. Three months prior, his HbA1c was 8.2% when he was started on metformin. He does not have any complaints on this visit. His temperature is 37°C (98.6°F), respirations are 15/min, pulse is 67/min and blood pressure is 122/88 mm Hg. His BMI is 33. Physical examination is within normal limits. Blood is drawn for laboratory tests and the results are given below:\nFasting blood glucose 150 mg/dL\nGlycated hemoglobin (HbA1c) 7.2 %\nSerum Creatinine 1.1 mg/dL\nBUN 12 mg/dL\nThe physician wants to initiate another medication for his blood glucose control, specifically one that does not carry a risk of weight gain. Addition of which of the following drugs would be most suitable for this patient?", "answer": "Sitagliptin", "options": {"A": "Glimepiride", "B": "Rosiglitazone", "C": "Pioglitazone", "D": "Sitagliptin", "E": "Glyburide"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 24-year-old man presents to the college campus clinic worried that he is having a nervous breakdown. The patient was diagnosed with attention-deficit/hyperactivity disorder (ADHD) during his freshman year and has been struggling to keep his grades up. He has recently become increasingly worried that he might not be able to graduate on time. For the past 2-months, he has been preoccupied with thoughts of his dorm room burning down and he finds himself checking all the appliances and outlets over and over even though he knows he already checked everything thoroughly. This repetitive behavior makes him late to class and has seriously upset his social activities. The patient is afebrile and vital signs are within normal limits. Physical examination is unremarkable. Which of the following psychiatric disorders is most associated with this patient’s condition?", "answer": "Tourette syndrome", "options": {"A": "Tourette syndrome", "B": "Obsessive-compulsive personality disorder", "C": "Schizophrenia", "D": "Delusional disorder", "E": "Not related to other disorders"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 49-year-old male complains of abdominal discomfort that worsens following meals. A gastric biopsy reveals a 2 cm gastric ulcer, and immunohistochemical staining demonstrates the presence of a rod-shaped bacterium in the gastric mucosa. Which of the following is used by the infiltrating pathogen to neutralize gastric acidity?", "answer": "Urease", "options": {"A": "Flagella", "B": "Mucinase", "C": "Bismuth", "D": "Urease", "E": "LT toxin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to the emergency department by his mother 1 hour after falling off his bike and landing head-first on the pavement. His mother says that he did not lose consciousness but has been agitated and complaining about a headache since the event. He has no history of serious illness and takes no medications. His temperature is 37.1°C (98.7°F), pulse is 115/min, respirations are 20/min, and blood pressure is 100/65 mm Hg. There is a large bruise on the anterior scalp. Examination, including neurologic examination, shows no other abnormalities. A noncontrast CT scan of the head shows a non-depressed linear skull fracture with a 2-mm separation. Which of the following is the most appropriate next step in management?", "answer": "Inpatient observation", "options": {"A": "Inpatient observation", "B": "Discharge home", "C": "Contact child protective services", "D": "MRI of the brain", "E": "CT angiography\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 67-year-old man presents to the emergency department with altered mental status. The patient is non-verbal at baseline, but his caretakers at the nursing home noticed he was particularly somnolent recently. The patient has a past medical history of diabetes and Alzheimer dementia. His temperature is 99.7°F (37.6°C), blood pressure is 157/98 mmHg, pulse is 150/min, respirations are 16/min, and oxygen saturation is 98% on room air. Laboratory values are obtained and shown below.\n\nHemoglobin: 9 g/dL\nHematocrit: 33%\nLeukocyte count: 8,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 102 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 37 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 2.4 mg/dL\nCa2+: 12.2 mg/dL\n\nThe patient has lost 20 pounds over the past month. His parathyroid hormone is within normal limits, and his urinary calcium is increased. Physical exam demonstrates discomfort when the patient's lower back and extremities are palpated. Which of the following is the most accurate diagnostic test for this patient's underlying diagnosis?", "answer": "Bone marrow biopsy", "options": {"A": "Bone marrow biopsy", "B": "Peripheral blood smear", "C": "Radiograph of the lumbar spine", "D": "Urine, blood, and cerebrospinal fluid cultures", "E": "Urine protein levels"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 31-year-old G1P0 woman is brought into the emergency room by the police after a failed suicide attempt. She jumped off a nearby bridge but was quickly rescued by some nearby locals. The height of the bridge was not significant, so the patient did not sustain any injuries. For the 3 weeks before this incident, the patient says she had been particularly down, lacking energy and unable to focus at home or work. She says she no longer enjoys her usual hobbies or favorite meals and is not getting enough sleep. Which of the following is the best course of treatment for this patient?", "answer": "Electroconvulsive therapy", "options": {"A": "Electroconvulsive therapy", "B": "Paroxetine", "C": "Phenelzine", "D": "Combination of SSRI and SNRI", "E": "Bupropion"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman is brought into the emergency room by her boyfriend with a superficial cut to the wrist. Her vital signs are normal.  On physical examination, the laceration is superficial and bleeding has stopped. She says that the injury was self-inflicted because her boyfriend canceled a dinner date due to his mother being unexpectedly hospitalized. She had tried to call, email, and text him to make sure he kept the date, but he eventually stopped replying to her messages. She loves her boyfriend and says she cannot live without him. However, she was worried that he might be cheating on her and using his mother as an excuse. She admits, however, that he actually has never cheated on her in the past. While she says that she usually feels emotionally empty, she is furious during the interview as she describes how much she hates her boyfriend. Which of the following defense mechanisms is this patient exhibiting?", "answer": "Splitting", "options": {"A": "Splitting", "B": "Repression", "C": "Suppression", "D": "Regression", "E": "Transference"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 29-year-old female presents to the family physician concerned over the blue-black discoloration of her sclera and skin. She notes that at the end of her day, there are black stains in her underwear. The incomplete breakdown of which of the following amino acids is responsible for this presentation?", "answer": "Tyrosine", "options": {"A": "Tyrosine", "B": "Valine", "C": "Leucine", "D": "Isoleucine", "E": "Methionine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman presents as a new patient to a primary care physician. She hasn't seen a doctor in many years and came in for a routine check-up. She has no specific complaints, although she has occasional shortness of breath with mild activity. On physical exam, her vital signs are as follows: HR 80, BP 110/70, RR 14. On auscultation, her lungs are clear with equal breath sounds bilaterally. When listening over the precordium, the physician hears a mid-systolic click followed by a late systolic murmur that is loudest over the apex. Valsalva increases the murmur. Which of the following is NOT a possible complication of this patient's underlying problem?", "answer": "Bleeding from acquired von Willebrand disease", "options": {"A": "Atrial fibrilation", "B": "Infective endocarditis", "C": "Bleeding from acquired von Willebrand disease", "D": "Cerebral embolism", "E": "Sudden death"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old woman seeks evaluation at a clinic complaining of shaking, chills, fevers, and headaches for the last 3 days. She recently returned from a trip to India, where she was visiting her family. There is no history of loss of consciousness or respiratory distress. The vital signs include temperature 38.9℃ (102.0℉), respiratory rate 19/min, blood pressure 120/80 mm Hg, and pulse 94/min (rapid and thready). On general examination, she is pale and the sclera is jaundiced. Laboratory studies show:\nHematocrit (Hct) 30%\nTotal bilirubin  2.6 mg/dL\nDirect bilirubin  0.3 mg/dL\nA peripheral smear is shown below. What is the most severe complication of this condition?", "answer": "Cerebral edema", "options": {"A": "Heart block", "B": "Facial paralysis", "C": "Cerebral edema", "D": "Aplastic crisis", "E": "Rheumatoid arthritis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 13-year-old girl is brought to the physician by her mother because of a 1-year history of worsening clumsiness. Initially, she swayed while walking; over the past 3 months, she has fallen 4 times. Ophthalmic examination shows a horizontal nystagmus. Proprioception and vibratory sensation are decreased in the distal extremities. Deep tendon reflexes are 1+ bilaterally. Further evaluation of the patient shows a genetic disorder involving an iron-binding mitochondrial protein encoded on chromosome 9. Which of the following findings is most likely to also be seen in this patient?", "answer": "Hammer toes", "options": {"A": "Hyperpigmented skin", "B": "Telangiectasias", "C": "Hammer toes", "D": "Myoclonic jerks", "E": "Adenoma sebaceum"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 36-year-old man comes to the physician because of a 2-day history of malaise and a painful, pruritic rash on his lower back and thighs. His temperature is 37.8°C (100°F). Physical examination shows the findings in the photograph. Skin scrapings from the thigh grow neutral colonies on MacConkey agar. The colony-producing bacteria are oxidase-positive. Which of the following is the greatest risk factor for the patient's condition?", "answer": "Swimming in pool", "options": {"A": "Swimming in pool", "B": "Unprotected sexual intercourse", "C": "Rose pruning", "D": "Skin-to-skin contact", "E": "Outdoor camping"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-month-old baby boy and his mother present to his pediatrician for vaccination as per the immunization schedule. His mother denies any active complaints but mentions that he has not smiled yet. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. His mother received minimal prenatal care. On physical examination, his vitals are stable, but a general examination shows the presence of generalized hypotonia. His face is characterized by upwardly slanting palpebral fissures, small dysplastic ears, and a flat face. His little fingers are short, with clinodactyly, and both palms have single palmar creases. The results of a karyotype are shown in the image. If this infant has also inherited a mutation in the GATA1 gene, for which of the following conditions is he most likely to be at increased risk?", "answer": "Acute megakaryoblastic leukemia", "options": {"A": "Acute megakaryoblastic leukemia", "B": "Celiac disease", "C": "Congenital hypothyroidism", "D": "Congenital cataracts", "E": "Endocardial cushion defect"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman presents to the emergency department with fever, cough, and difficulty in breathing for the last 6 hours. She also mentions that she noticed some blood in her sputum an hour ago. She denies nasal congestion or discharge, sneezing, wheezing, chest pain, or palpitation. Her past history does not suggest any chronic medical condition, including respiratory disease, cardiovascular disease, or cancer. There is no history of pulmonary embolism or deep vein thrombosis in the past. Her temperature is 38.3°C (101.0°F ), the pulse is 108/min, the blood pressure is 116/80 mm Hg, and the respirations are 28/min. Auscultation of her lungs reveals the presence of localized crackles over the right inframammary region. Edema is present over her left leg and tenderness is present over her left calf region. When her left foot is dorsiflexed, she complains of calf pain. The emergency department protocol mandates the use of a modified Wells scoring system in all patients presenting with the first episode of breathlessness when there is no history of a cardiorespiratory disorder in the past. Using the scoring system, the presence of which of the following risk factors would suggest a high clinical probability of pulmonary embolism?", "answer": "History of surgery within the last 30 days", "options": {"A": "Use of oral contraceptives within last 90 days", "B": "Intravenous drug use within last 14 days", "C": "History of travel of 2 hours in 30 days", "D": "History of surgery within the last 30 days", "E": "History of smoking for more than 1 year"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man comes to the physician because of a 5-day history of swelling in his left arm. Two months ago, he was diagnosed with a deep venous thrombosis in the left calf. He has had a 7-kg (15-lb) weight loss in the last 3 months. He has smoked 1 pack of cigarettes daily for the past 25 years. His only medication is warfarin. Physical examination shows warm edema of the left forearm with overlying erythema and a tender, palpable cord-like structure along the medial arm. His lungs are clear to auscultation bilaterally. Duplex sonography shows thrombosis of the left basilic and external jugular veins. Which of the following is the most appropriate next step to confirm the underlying diagnosis?", "answer": "CT scan of the abdomen", "options": {"A": "X-ray of the chest", "B": "Transesophageal echocardiography", "C": "CT scan of the abdomen", "D": "Serum antiphospholipid antibody level", "E": "Serum D-dimer level"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-day-old infant girl is brought to the emergency department because of a 2-hour history of fever, vomiting, and diarrhea. She has fed less and has had decreased urine output for 1 day. She was born at 33 weeks' gestation and weighed 1400-g (3-lb 1-oz). Her diet consists of breast milk and cow milk protein-based formula. Examination shows abdominal rigidity, distention, and absent bowel sounds. Test of the stool for occult blood is positive. An x-ray of the abdomen shows gas within the intestinal wall and the peritoneal cavity. Which of the following is the most likely diagnosis?", "answer": "Necrotizing enterocolitis", "options": {"A": "Meckel diverticululum", "B": "Cow milk protein allergy", "C": "Hirschsprung disease", "D": "Hypertrophic pyloric stenosis", "E": "Necrotizing enterocolitis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 42-year-old woman comes to the physician because of a 7-month history of diffuse weakness. There is no cervical or axillary lymphadenopathy. Cardiopulmonary and abdominal examination shows no abnormalities. A lateral x-ray of the chest shows an anterior mediastinal mass. Further evaluation of this patient is most likely to show which of the following?", "answer": "Acetylcholine receptor antibodies", "options": {"A": "Acetylcholine receptor antibodies", "B": "Smoking history of 30 pack years", "C": "Elevated serum alpha-fetoprotein level", "D": "History of fever, night sweats, and weight loss", "E": "Increased urinary catecholamines"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old patient presents to the emergency department with left wrist pain after falling off of his bike and landing on his left hand. On physical exam the thenar eminence is red, swollen, and tender to palpation, so a radiograph is ordered. The patient is worried because he learned in biology class that radiography can cause cancer through damaging DNA but the physician reassures him that radiographs give a very minor dose of radiation. What is the most common mechanism by which ionizing radiation damages DNA?", "answer": "Strand breakage", "options": {"A": "Thymidine dimer formation", "B": "Microsatellite instability", "C": "Cytosine deamination", "D": "Strand breakage", "E": "Cyclobutane pyrimidine dimer formation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old G3P2 presents at 33 weeks gestation with vaginal bleeding that started last night while she was asleep. She denies uterine contractions or abdominal pain. She had a cesarean delivery in her previous pregnancy. She also reports a 10 pack-year smoking history. The vital signs are as follows: blood pressure, 130/80 mm Hg; heart rate, 84/min; respiratory rate, 12/min; and temperature, 36.8℃ (98.2℉). The physical examination is negative for abdominal tenderness or palpable uterine contractions. The perineum is mildly bloody. On speculum examination, no vaginal or cervical lesions are seen. A small amount of blood continues to pass through the cervix. Which of the following findings would you expect on ultrasound examination?", "answer": "Partial covering of the internal cervical os by the placental edge", "options": {"A": "Partial covering of the internal cervical os by the placental edge", "B": "Retroplacental blood accumulation", "C": "Placental calcification", "D": "Cysts on the placental surface", "E": "Loss of the clear retroplacental space"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A group of scientists is conducting an experiment on the human cells involved in the immune response. They genetically modify B cells so they do not express the cluster of differentiation 21 (CD21) on their cell surfaces. The pathogenesis of which of the following organisms would most likely be affected by this genetic modification?", "answer": "Epstein-Barr virus (EBV)", "options": {"A": "Epstein-Barr virus (EBV)", "B": "Measles virus", "C": "Human immunodeficiency virus (HIV)", "D": "Human papillomavirus", "E": "Parvovirus B19"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 13-year-old boy is brought to the physician by his parents, who are concerned about recurrent muscle cramps he experiences while playing soccer. The boy has always loved sports and has been playing in a soccer league for the past 3 years. He now complains of severe cramping pain in his legs after intense practice sessions. He has no significant medical history. His physical examination is unremarkable. A battery of laboratory tests is ordered and they are all normal. Imaging studies yield no abnormalities as well. Which of the following is most likely deficient in this patient?", "answer": "Carnitine palmitoyltransferase II", "options": {"A": "Carnitine palmitoyltransferase I", "B": "Carnitine palmitoyltransferase II", "C": "Medium-chain acyl-coenzyme A dehydrogenase", "D": "Myophosphorylase", "E": "Reye syndrome"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old male presents to his primary care physician for a regularly scheduled check-up. Physical examination reveals nontender cervical lymphadenopathy. A biopsy of the lymph node reveals aggregates of follicular architecture, and cytogenic analysis shows a t(14;18) translocation. The protein most likely responsible for the patient’s condition does which of the following:", "answer": "Inhibits apoptosis", "options": {"A": "Regulates passage through the cell cycle", "B": "Activates DNA repair proteins", "C": "Provides mitotic cytoskeleton", "D": "Inhibits apoptosis", "E": "Regulates cell growth through signal transduction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman comes to the physician for the evaluation of blindness in her right eye that suddenly started 1 hour ago. She has no feeling of pain, pressure, or sensation of a foreign body in the right eye. She has a history of major depressive disorder treated with fluoxetine. The patient attends college and states that she has had a lot of stress lately due to relationship problems with her partner. She does not smoke or drink alcohol. She does not use illicit drugs. She appears anxious. Her vital signs are within normal limits. Ophthalmologic examination shows a normal-appearing eye with no redness. Slit lamp examination and fundoscopy show no abnormalities. A visual field test shows nonspecific visual field defects. An MRI of the brain shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Conversion disorder", "options": {"A": "Malingering", "B": "Factitious disorder", "C": "Retinal detachment", "D": "Somatic symptom disorder", "E": "Conversion disorder"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 52-year-old woman presents to the clinic with several days of vomiting and diarrhea. She also complains of headaches, muscle aches, and fever, but denies tenesmus, urgency, and bloody diarrhea. Past medical history is insignificant. When asked about any recent travel she says that she just came back from a cruise ship vacation. Her temperature is 37°C (98.6° F), respiratory rate is 15/min, pulse is 67/min, and blood pressure is 122/98 mm Hg. Physical examination is non-contributory. Microscopic examination of the stool is negative for ova or parasites. What is the most likely diagnosis?", "answer": "Norovirus infection", "options": {"A": "Giardiasis", "B": "C. difficile colitis", "C": "Irritable bowel syndrome", "D": "Norovirus infection", "E": "Traveler’s diarrhea due to ETEC"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old female presents to the emergency room with headache and palpitations. She is sweating profusely and appears tremulous on exam. Vital signs are as follows: HR 120, BP 190/110, RR 18, O2 99% on room air, and Temp 37C. Urinary metanephrines and catechols are positive. Which of the following medical regimens is contraindicated as a first-line therapy in this patient?", "answer": "Propranolol", "options": {"A": "Phenoxybenzamine", "B": "Nitroprusside", "C": "Propranolol", "D": "Labetalol", "E": "Lisinopril"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 9-year-old boy is brought to the physician for evaluation of short stature. He is at the 5th percentile for height, 65th percentile for weight, and 95th percentile for head circumference. Examination shows midface retrusion, a bulging forehead, and flattening of the nose. The extremities are disproportionately short. He was adopted and does not know his biological parents. The patient’s condition is an example of which of the following genetic phenomena?", "answer": "Complete penetrance", "options": {"A": "Anticipation", "B": "Variable expressivity", "C": "Imprinting", "D": "Complete penetrance", "E": "Codominance"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old woman comes to the physician for week-long episodes of headaches that have occurred every four weeks for the last year. During these episodes she also has bouts of lower abdominal pain and breast tenderness. She is often irritable at these times. Her menses occur at regular 28-day intervals with moderate flow. Her last menstrual period was 3 weeks ago. She drinks two to five beers on social occasions and used to smoke a pack of cigarettes daily, but stopped 6 months ago. Her mother and sister have hypothyroidism. Physical examination shows no abnormalities. Which of the following is most likely to confirm the diagnosis?", "answer": "Maintaining a menstrual diary", "options": {"A": "Detailed psychosocial assessment", "B": "Therapeutic trial with nicotine gum", "C": "Assessment of thyroid hormones", "D": "Serial measurements of gonadotropin levels", "E": "Maintaining a menstrual diary"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 51-year-old woman presents for her annual wellness visit. She says she feels healthy and has no specific concerns. Past medical history is significant for bipolar disorder, hypertension, and diabetes mellitus type 2, managed with lithium, lisinopril, and metformin, respectively. Her family history is significant for hypertension and diabetes mellitus type 2 in her father, who died from lung cancer at age 67. Her vital signs include: temperature 36.8°C (98.2°F), pulse 97/min, respiratory rate 16/min, blood pressure 120/75 mm Hg. Physical examination is unremarkable. Mammogram findings are labeled breast imaging reporting and data system-3 (BIRADS-3) (probably benign). Which of the following is the next best step in management in this patient?", "answer": "Follow-up mammogram in 6 months", "options": {"A": "Follow-up mammogram in 1 year", "B": "Follow-up mammogram in 6 months", "C": "Breast MRI", "D": "Biopsy", "E": "Treatment"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old woman comes to the physician because of right-sided inguinal pain for the past 8 weeks. During this period, the patient has had increased pain during activities such as walking and standing. She has no nausea, vomiting, or fever. Her temperature is 36.8°C (98.2°F), pulse is 73/min, and blood pressure is 132/80 mm Hg. The abdomen is soft and nontender. There is a visible and palpable groin protrusion above the inguinal ligament on the right side. Bulging is felt during Valsalva maneuver. Which of the following is the most likely diagnosis?", "answer": "Indirect inguinal hernia", "options": {"A": "Lipoma", "B": "Indirect inguinal hernia", "C": "Inguinal lymphadenopathy", "D": "Direct inguinal hernia", "E": "Strangulated hernia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man presents to the emergency department with decreased exercise tolerance and shortness of breath which has progressed slowly over the past month. The patient recalls that shortly before the onset of these symptoms, he had a low-grade fever, malaise, and sore throat which resolved after a few days with over the counter medications. He does not have any chronic illnesses and denies recent travel or illicit habits. His vital signs include: blood pressure 120/80 mm Hg, temperature 37.0°C (98.6°F), and regular radial pulse 90/min. While checking his blood pressure manually, the difference between the systolic pressure at which the first Korotkoff sounds are heard during expiration and the pressure at which they are heard throughout the respiratory cycle is less than 10 mm Hg. On physical examination, he is in mild distress with jugular venous pressure (JVP) of 13 cm, and his heart sounds are muffled. His echocardiography shows a fluid collection in the pericardial sac with no evidence of right ventricular compression. Which of the following is the best initial step for the treatment of this patient?", "answer": "Observation and anti-inflammatory medicines", "options": {"A": "Pericardiocentesis", "B": "Surgical drainage", "C": "Pericardiectomy", "D": "Observation and anti-inflammatory medicines", "E": "Prednisone"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought to the physician for excessive weight gain. The mother reports that her son has been “chubby” since he was a toddler and that he has gained 10 kg (22 lbs) over the last year. During this period, he fractured his left arm twice from falling on the playground. He had cryptorchidism requiring orchiopexy at age 2. He is able to follow 1-step instructions and uses 2-word sentences. He is at the 5th percentile for height and 95th percentile for weight. Vital signs are within normal limits. Physical examination shows central obesity. There is mild esotropia and coarse, dry skin. In addition to calorie restriction, which of the following is the most appropriate next step in management of this patient?", "answer": "Growth hormone and testosterone", "options": {"A": "Fluoxetine", "B": "Octreotide", "C": "Laparoscopic gastric banding", "D": "Growth hormone and testosterone", "E": "Levothyroxine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old man comes to the physician because of a 2-year history of gradually worsening shortness of breath. He smoked half a pack of cigarettes daily for 10 years but stopped 8 years ago. His pulse is 72/min, blood pressure is 135/75 mm Hg, and respirations are 20/min. Examination shows an increased anteroposterior diameter of the chest. Diminished breath sounds are heard on auscultation of the chest. An x-ray of the chest shows widened intercostal spaces, a flattened diaphragm, and bilateral hyperlucency of the lung bases. This patient's condition puts him at greatest risk for which of the following conditions?", "answer": "Hepatocellular carcinoma", "options": {"A": "Antineutrophil cytoplasmic antibody-positive vasculitis", "B": "Hepatocellular carcinoma", "C": "Bronchiolitis obliterans", "D": "IgA nephropathy", "E": "Bronchogenic carcinoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3-year-old boy presents to an urgent care clinic with his mother. She states that his behavior has been lethargic for the past 3 days. She also notes that he has had a runny nose, mild cough, and sore throat during this time. She does not believe that he has been febrile. His temperature is 99.1°F (37.2°C), blood pressure is 105/67 mmHg, pulse is 100/min, respirations are 18/min, and SpO2 97% on room air. Which nucleic acid structure most accurately describes the most likely virus responsible for this boy’s clinical condition?", "answer": "Single-stranded, positive-sense RNA", "options": {"A": "Single-stranded, positive-sense RNA", "B": "Single-stranded, negative-sense RNA", "C": "Double-stranded RNA", "D": "Single-stranded DNA", "E": "Double-stranded DNA"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 26-year-old male with no significant past medical history goes camping with several friends in Virginia. Several days after returning, he begins to experience fevers, headaches, myalgias, and malaise. He also notices a rash on his wrists and ankles (FIgure A). Which of following should be initiated for treatment of his condition?", "answer": "Doxycycline", "options": {"A": "Pyrazinamide", "B": "Praziquantel", "C": "Vancomycin", "D": "Azithromycin", "E": "Doxycycline"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An obese 63-year-old man comes to the physician because of 3 episodes of red urine over the past week. He has also had recurrent headaches and intermittent blurry vision during the past month. He has benign prostatic hyperplasia. He works as an attendant at a gas station. The patient has smoked one pack of cigarettes daily for the last 40 years. He does not drink alcohol. Current medications include tamsulosin. His temperature is 37.4°C (99.4°F), pulse is 90/min, and blood pressure is 152/95 mm Hg. Examination shows a flushed face. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and non-tender. Digital rectal examination shows an enlarged prostate with no nodules. Urinalysis shows:\nBlood 3+\nGlucose negative\nProtein negative\nWBC 1-2/hpf\nRBC 40-45/hpf\nRBC casts none\nWhich of the following is the most likely diagnosis?\"", "answer": "Renal cell carcinoma", "options": {"A": "Nephrolithiasis", "B": "IgA nephropathy", "C": "Transitional cell bladder carcinoma", "D": "Renal oncocytoma", "E": "Renal cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old man presents to the emergency department after a suicide attempt. He is admitted to the hospital and diagnosed with schizoaffective disorder. A review of medical records reveals a history of illicit drug use, particularly cocaine and amphetamines. He is started on aripiprazole, paroxetine, and trazodone. At the time of discharge, he appeared more coherent and with a marked improvement in positive symptoms of hallucinations and delusions but still with a flat effect. During the patient’s first follow-up visit, his mother reports he has become increasingly agitated and restless despite compliance with his medications. She reports that her son’s hallucinations and delusions have stopped and he does not have suicidal ideations, but he cannot sit still and continuously taps his feet, wiggles his fingers, and paces in his room. When asked if anything is troubling him, he stands up and paces around the room. He says, “I cannot sit still. Something is happening to me.” A urine drug screen is negative. What is the next best step in the management of this patient?", "answer": "Add propranolol", "options": {"A": "Add lithium", "B": "Add propranolol", "C": "Increase the aripiprazole dose", "D": "Stop aripiprazole and switch to clozapine", "E": "Stop paroxetine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man visits the clinic with his wife. He has had difficulty swallowing solid foods for the past 2 months. His wife adds that his voice is getting hoarse but they thought it was due to his recent flu. His medical history is significant for type 2 diabetes mellitus for which he is on metformin. He suffered from many childhood diseases due to lack of medical care and poverty. His blood pressure is 125/87 mm Hg, pulse 95/min, respiratory rate 14/min, and temperature 37.1°C (98.7°F). On examination, an opening snap is heard over the cardiac apex. An echocardiogram shows an enlarged cardiac chamber pressing into his esophagus. Changes in which of the following structures is most likely responsible for this patient’s symptoms?", "answer": "Left atrium", "options": {"A": "Left ventricle", "B": "Left atrium", "C": "Right atrium", "D": "Right ventricle", "E": "Patent ductus arteriosus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the physician for generalized fatigue and multiple episodes of abdominal pain and vomiting for the past week. His last bowel movement was 4 days ago. He has been having behavioral problems at home for the past few weeks as well. He can walk up stairs with support and build a tower of 3 blocks. He cannot use a fork. He does not follow simple instructions and speaks in single words. His family emigrated from Bangladesh 6 months ago. He is at the 40th percentile for height and weight. His temperature is 37°C (98.6°F), pulse is 115/min, and blood pressure is 84/45 mm Hg. Examination shows pale conjunctivae and gingival hyperpigmentation. His hemoglobin concentration is 10.1 g/dL, mean corpuscular volume is 68 μm3, and mean corpuscular hemoglobin is 24.5 pg/cell. The patient is most likely going to benefit from administration of which of the following?", "answer": "Succimer and calcium disodium edetate", "options": {"A": "Succimer and calcium disodium edetate", "B": "Thiosulfate and hydroxocobalamin", "C": "Vitamin B12 and folate", "D": "Penicillamine", "E": "Iron"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 74-year-old man presents to the emergency department by paramedics for slurred speech and weakness in the left arm and leg for 1 hour. The patient was playing with his grandson when the symptoms started and his wife immediately called an ambulance. There is no history of head trauma or recent surgery. The patient takes captopril for hypertension. The vital signs include: pulse 110/min, respiratory rate 22/min, and blood pressure 200/105 mm Hg. The physical examination shows that the patient is alert and conscious, but speech is impaired. Muscle strength is 0/5 in the left arm and leg and 5/5 in the right arm and leg. A non-contrast CT of the head shows no evidence of intracranial bleeding. The lab results are as follows:\nSerum glucose 90 mg/dL\nSodium 140 mEq/L\nPotassium 4.1 mEq/L\nChloride 100 mEq/L\nSerum creatinine 1.3 mg/dL\nBlood urea nitrogen 20 mg/dL\nCholesterol, total 240 mg/dL\nHDL-cholesterol 38 mg/dL\nLDL-cholesterol 100 mg/dL\nTriglycerides 190 mg/dL\nHemoglobin (Hb%) 15.3 g/dL\nMean corpuscular volume (MCV) 83 fL\nReticulocyte count 0.8%\nErythrocyte count 5.3 million/mm3\nPlatelet count 130,000/mm3\nPartial thromboplastin time (aPTT)  30 sec\nProthrombin time (PT) 12 sec\nAlthough he is within the time frame for the standard therapy of the most likely condition, the treatment cannot be started because of which of the following contraindications?", "answer": "Systolic blood pressure of 200 mm Hg", "options": {"A": "Creatinine level of 1.3 mg/dL", "B": "A platelet count of 130,000/mm3", "C": "Cholesterol level of 240 mg/dL", "D": "Systolic blood pressure of 200 mm Hg", "E": "Age of 74 years"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old African American woman presents to the office complaining of blurry vision and headache for the past 2 weeks. She states that she has not been feeling herself lately and also fell down once after a dizzy episode. Her medical history is remarkable for hypertension and pulmonary sarcoidosis treated with hydralazine and prednisone respectively. She had a recent bout of acute optic neuritis, requiring high-dose IV methylprednisolone. Her temperature is 37°C (98.6°F), the blood pressure is 112/76 mm Hg, the pulse is 78/min, and the respirations are 14/min. On examination, the patient is mildly disoriented. Head and neck examination reveals a soft, supple neck and a right-sided facial droop. There is 5/5 muscle strength in all extremities. VDRL test is negative. A head MRI is pending. What is the most appropriate next step in the management of this patient?\n ", "answer": "Methylprednisolone and methotrexate", "options": {"A": "Methotrexate", "B": "Methylprednisolone and methotrexate", "C": "Heparin", "D": "Plasmapheresis", "E": "Methotrexate and azathioprine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 54-year-old man comes to the emergency department because of episodic palpitations for the past 12 hours. He has no chest pain. He has coronary artery disease and type 2 diabetes mellitus. His current medications include aspirin, insulin, and atorvastatin. His pulse is 155/min and blood pressure is 116/77 mm Hg. Physical examination shows no abnormalities. An ECG shows monomorphic ventricular tachycardia. An amiodarone bolus and infusion is given, and the ventricular tachycardia converts to normal sinus rhythm. He is discharged home with oral amiodarone. Which of the following is the most likely adverse effect associated with long-term use of this medication?", "answer": "Chronic interstitial pneumonitis", "options": {"A": "Hepatic adenoma", "B": "Shortened QT interval on ECG", "C": "Chronic interstitial pneumonitis", "D": "Angle-closure glaucoma", "E": "Progressive multifocal leukoencephalopathy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old woman is brought to the hospital by her mother because she has \"not been herself\" for the past 3 months. The patient says she hears voices in her head. The mother said that when she is talking to her daughter she can’t seem to make out what she is saying; it is as if her thoughts are disorganized. When talking with the patient, you notice a lack of energy and an apathetic affect. Which of the following is the most likely diagnosis for this patient?", "answer": "Schizophreniform disorder", "options": {"A": "Major depressive disorder", "B": "Brief psychotic disorder", "C": "Schizotypal disorder", "D": "Schizophreniform disorder", "E": "Schizophrenia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old girl is brought to the emergency department by her parents because of a painful rash of her hands and lower arms. According to the mother, she developed blisters and redness on her arms 2 days ago. Both parents claim there is no recent history of fever, itching, or trauma. Physical examination shows erythema and multiple fluid-filled bullae on the hands and arms up to the elbows with intermittent stripes of normal skin seen on the palmar aspect of the hand. The lesions are symmetrical in distribution and are sharply delineated. Which of the following is the most appropriate next step in management?", "answer": "Notify Child Protective Services", "options": {"A": "Schedule a follow-up examination for further evaluation", "B": "Notify Child Protective Services", "C": "Ask both parents to leave the examination room to perform a forensic interview of the child", "D": "Talk to both parents individually", "E": "Obtain a biopsy specimen of the skin lesions for histopathological examination\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year-old man is brought to the emergency department for confusion. He was in his usual state of health until about 3 hours ago when he tried to use his sandwich to turn off the TV. He also complained to his wife that he had a severe headache. Past medical history is notable for hypertension, which has been difficult to control on multiple medications. His temperature is 36.7°C (98°F), the pulse is 70/min, and the blood pressure is 206/132 mm Hg. On physical exam he is alert and oriented only to himself, repeating over and over that his head hurts. The physical exam is otherwise unremarkable and his neurologic exam is nonfocal. The noncontrast CT scan of the patient’s head is shown. Which of the following diagnostic tests is likely to reveal the diagnosis for this patient?", "answer": "MRI of the brain", "options": {"A": "CT angiography of the brain", "B": "CT angiography of the neck", "C": "Electroencephalogram (EEG)", "D": "Lumbar puncture", "E": "MRI of the brain"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old man is brought into the emergency department by his daughter for a change in behavior. Yesterday the patient seemed more confused than usual and was asking the same questions repetitively. His symptoms have not improved over the past 24 hours, thus the decision to bring him in today. Last year, the patient was almost completely independent but he then suffered a \"series of falls,\" after which his ability to care for himself declined. After this episode he was no longer able to cook for himself or pay his bills but otherwise had been fine up until this episode. The patient has a past medical history of myocardial infarction, hypertension, depression, diabetes mellitus type II, constipation, diverticulitis, and peripheral neuropathy. His current medications include metformin, insulin, lisinopril, hydrochlorothiazide, sodium docusate, atorvastatin, metoprolol, fluoxetine, and gabapentin. On exam you note a confused man who is poorly kept. He has bruises over his legs and his gait seems unstable. He is alert to person and place, and answers some questions inappropriately. The patient's pulse is 90/minute and his blood pressure is 170/100 mmHg. Which of the following is the most likely diagnosis?", "answer": "Vascular dementia", "options": {"A": "Normal aging", "B": "Alzheimer's dementia", "C": "Lewy body dementia", "D": "Vascular dementia", "E": "Presbycusis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 33-year-old woman presents to her primary care physician for a wellness check-up. She states that recently she has been feeling well other than headaches that occur occasionally, which improve with ibuprofen and rest. She has a past medical history of hypertension and headaches and is currently taking hydrochlorothiazide. Her temperature is 99.2°F (37.3°C), blood pressure is 157/108 mmHg, pulse is 90/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam reveals a young woman who appears healthy. A normal S1 and S2 are auscultated on cardiac exam, and her lungs are clear with good air movement bilaterally. From her previous visit, it was determined that she has an elevated aldosterone and low renin level. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 3.7 mEq/L\nHCO3-: 29 mEq/L\nBUN: 20 mg/dL\nCreatinine: 1.1 mg/dL\n\nWhich of the following is the most likely diagnosis?", "answer": "Primary hyperaldosteronism", "options": {"A": "Benign essential hypertension", "B": "Cushing syndrome", "C": "Narrowing of the renal arteries", "D": "Pheochromocytoma", "E": "Primary hyperaldosteronism"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old man is brought to the physician 25 minutes after an episode of violent jerky movements of his hands and legs that lasted for 5 minutes. After the episode, he had difficulty conversing. For the past 10 days, he has had a left-sided headache and nausea. Apart from a history of recurrent ear infections treated with antibiotics, he reports no other personal or family history of serious illness. He works as an assistant at a veterinarian clinic. He appears ill and is oriented to place and person only. His temperature is 37.8°C (100°F), pulse is 102/min, and blood pressure 112/78 mm Hg. Examination shows bilateral optic disc swelling. There is no lymphadenopathy. Muscle strength and tone is normal in all extremities. Deep tendon reflexes are 2+ bilaterally. Plantar reflex shows a flexor response bilaterally. Laboratory studies show a CD4 count within the reference range. An MRI of the brain is shown. Intravenous mannitol and levetiracetam are administered. Which of the following is the most appropriate next step in management?", "answer": "Aspiration and surgical drainage", "options": {"A": "Ciprofloxacin and metronidazole therapy", "B": "Metronidazole and cefotaxime therapy", "C": "Aspiration and surgical drainage", "D": "Albendazole therapy", "E": "Pyrimethamine and sulfadiazine therapy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 12-year-old girl is brought to the physician by her mother because of high fever and left ankle and knee joint swelling. She had a sore throat 3 weeks ago. There is no family history of serious illness. Her immunizations are up-to-date. She had an episode of breathlessness and generalized rash when she received dicloxacillin for a skin infection 2 years ago. She appears ill. Her temperature is 38.8°C (102.3°F), pulse is 87/min, and blood pressure is 98/62 mm Hg. Examination shows left ankle and knee joint swelling and tenderness; range of motion is limited. Breath sounds over both lungs are normal. A grade 3/6 holosytolic murmur is heard best at the apex. Abdominal examination is normal. Which of the following is the most appropriate pharmacotherapy?", "answer": "Clarithromycin", "options": {"A": "Clarithromycin", "B": "High-dose glucocorticoids", "C": "Amoxicillin", "D": "Methotrexate", "E": "Ciprofloxacin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 58-year-old woman with HIV infection is brought to the emergency department because of a 2-week history of headaches, blurred vision, and confusion. Her current medications include antiretroviral therapy and trimethoprim-sulfamethoxazole. Neurological examination shows ataxia and memory impairment. Her CD4+ T-lymphocyte count is 90/μL. Analysis of her cerebrospinal fluid analysis shows lymphocytic predominant pleocytosis, and PCR is positive for Epstein-Barr virus DNA. An MRI of the brain with contrast shows a solitary, weakly ring-enhancing lesion with well-defined borders involving the corpus callosum. Which of the following is the most likely diagnosis?", "answer": "Primary cerebral lymphoma", "options": {"A": "AIDS dementia", "B": "Cerebral toxoplasmosis", "C": "Primary cerebral lymphoma", "D": "Progressive multifocal leukoencephalopathy", "E": "Glioblastoma multiforme"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 19-year-old man presents to a psychiatrist for the management of substance abuse. He reports that he started using the substance 2 years ago and that he smokes it after sprinkling it on his cigarette. He describes that after smoking the substance, he feels excited and as if he does not belong to himself. He also reports that when he is in his room, he sees vivid colors on the walls after using the substance; if he listens to his favorite music, he clearly sees colors and shapes in front of his eyes. There is no history of alcohol or nicotine abuse. The psychiatrist goes through his medical records and notes that he had presented with acute substance intoxication 1 month prior. At that point, his clinical features included delusions, amnesia, generalized erythema of his skin, tachycardia, hypertension, dilated pupils, dysarthria, and ataxia. Which of the following signs is also most likely to have been present on physical examination while the man was intoxicated with the substance?", "answer": "Nystagmus", "options": {"A": "Nystagmus", "B": "Generalized hypotonia", "C": "Increased sensitivity to pain", "D": "Hyporeflexia", "E": "Excessive perspiration"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An experimental infusable drug, X729, is currently being studied to determine its pharmacokinetics. The drug was found to have a half life of 1.5 hours and is eliminated by first order kinetics. What is the minimum number of hours required to reach a steady state concentration of >90%?", "answer": "6", "options": {"A": "1.5", "B": "3", "C": "4.5", "D": "6", "E": "7.5"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old man comes to the physician for a follow-up examination. He feels well. His last visit to a physician was 3 years ago. He has chronic obstructive pulmonary disease, coronary artery disease, and hypertension. Current medications include albuterol, atenolol, lisinopril, and aspirin. He has smoked one pack of cigarettes daily for 18 years but stopped 20 years ago. He had a right lower extremity venous clot 15 years ago that required 3 months of anticoagulation therapy. A colonoscopy performed 3 years ago demonstrated 2 small, flat polyps that were resected. He is 175 cm (5 ft 9 in) tall and weighs 100 kg (220 lb); BMI is 32.5 kg/m2. His pulse is 85/min, respirations are 14/min, and blood pressure is 150/80 mm Hg. Examination shows normal heart sounds and no carotid or femoral bruits. Scattered minimal expiratory wheezing and rhonchi are heard throughout both lung fields. Which of the following health maintenance recommendations is most appropriate at this time?", "answer": "Abdominal ultrasonography", "options": {"A": "Pulmonary function testing", "B": "Abdominal ultrasonography", "C": "CT scan of the chest", "D": "Lower extremity ultrasonography", "E": "Bone densitometry scan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old retired shipyard worker received a chest x-ray as part of a routine medical work-up. The radiologist reported incidental findings suggestive of an occupational lung disease. Which of the following descriptions is most consistent with this patient's film?", "answer": "Fibrocalcific parietal pleural plaques on the diaphragm", "options": {"A": "Enlarged hilar lymph nodes", "B": "Fibrocalcific parietal pleural plaques on the diaphragm", "C": "Hyperinflated lungs with a loss of lung markings", "D": "Nodular calcium lesions in the apex of the lung", "E": "No specific radiographic findings"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old man presents to the clinic with a dull low back pain radiating to the buttocks. He first noted it about 2 years ago and it has; progressed since then. He notes that it is worse in the morning and improves later in the day after physical activity. The patient also reports morning stiffness lasting up to 30 minutes and blurred vision, which started about 7 months ago. The patient’s vital signs include: blood pressure 130/80 mm Hg, heart rate 88/min, respiratory rate 16/min, and temperature 36.8°C (98.2°F). Physical examination reveals tenderness over the sacroiliac joints and limitation of the lumbar spine movements in the sagittal plane. The patient’s X-ray is shown in the picture below. Which of the following HLA variants is associated with this patient’s condition?", "answer": "HLA-B27", "options": {"A": "HLA-DQ2", "B": "HLA-DR4", "C": "HLA-B47", "D": "HLA-B27", "E": "HLA-DR3"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old man who was admitted for a fractured hip and is awaiting surgery presents with acute onset altered mental status. The patient is noted by the nurses to be shouting and screaming profanities and has already pulled out his IV and urine catheter. He says he believes he is being kept against his will and does not recall falling or fracturing his hip. The patient must be restrained by the staff to prevent him from getting out of bed. He is refusing a physical exam. Initial examination reveals an agitated elderly man with a trickle of blood flowing down his left arm. He is screaming and swinging his fists at the staff. The patient is oriented x 1. Which of the following is the next, best step in the management of this patient?", "answer": "Administer an Antipsychotic", "options": {"A": "Administer an Antipsychotic", "B": "Repair the fractured hip", "C": "Change his medication", "D": "Order 24-hour restraints", "E": "Order CMP and CBC"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old woman comes to the physician for evaluation of a breast lump she noticed 2 days ago while showering. She has no history of major illness. Her mother died of ovarian cancer at age 38, and her sister was diagnosed with breast cancer at age 33. Examination shows a 1.5-cm, nontender, mobile mass in the upper outer quadrant of the left breast. Mammography shows pleomorphic calcifications. Biopsy of the mass shows invasive ductal carcinoma. The underlying cause of this patient's condition is most likely a mutation of a gene involved in which of the following cellular events?", "answer": "Repair of double-stranded DNA breaks", "options": {"A": "Activity of cytoplasmic tyrosine kinase", "B": "Arrest of cell cycle in G1 phase", "C": "Repair of double-stranded DNA breaks", "D": "Inhibition of programmed cell death", "E": "Regulation of intercellular adhesion"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 9-month-old boy is brought to the physician because of abnormal crawling and inability to sit without support. A 2nd-trimester urinary tract infection that required antibiotic use and a spontaneous preterm birth via vaginal delivery at 36 weeks’ gestation both complicated the mother’s pregnancy. Physical examination shows a scissoring posture of the legs when the child is suspended by the axillae. Examination of the lower extremities shows brisk tendon reflexes, ankle clonus, and upward plantar reflexes bilaterally. When encouraged by his mother, the infant crawls forward by using normal reciprocal movements of his arms, while his legs drag behind. A brain MRI shows scarring and atrophy in the white matter around the ventricles with ventricular enlargement. Which of the following is most likely associated with the findings in this child?", "answer": "Antenatal injury", "options": {"A": "Antenatal injury", "B": "Genetic defect", "C": "Intrapartum asphyxia", "D": "Postnatal head trauma", "E": "Preterm birth"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 69-year-old man is brought to the emergency room by his wife 30 minutes after losing consciousness while they were working in their garden together. The patient says that time seemed to slow down, his vision went dark, and he had a sensation of falling. After 3–5 seconds, he awoke slightly disoriented but quickly regained his baseline mental status. The patient says he has had a few similar episodes that occurred 1–2 months ago for which he did not seek any medical treatment. He says overall he has been more tired than usual and feeling out of breath on his morning walks. He denies any chest pain or palpitations. Past medical history is significant for type 1 diabetes mellitus. Current medications are atorvastatin and insulin. His family history is significant for his father who died of myocardial infarction in his 70’s. His blood pressure is 110/85 mm Hg and pulse is 82/min. On physical examination, there is a 3/6 systolic murmur best heard over the right sternal border with radiation to the carotids. S1 is normal but there is a soft unsplit S2. The lungs are clear to auscultation bilaterally. The remainder of the exam is unremarkable. Which of the following physical exam findings would also most likely be present in this patient?", "answer": "A slow-rising and delayed upstroke of the carotid pulse", "options": {"A": "A decrease in systolic blood pressure ≥ 10 mmHg during inspiration", "B": "A slow-rising and delayed upstroke of the carotid pulse", "C": "Distant heart sounds", "D": "Increased capillary pulsations of the fingertips", "E": "A carotid biphasic pulse"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 69-year-old man comes to the physician because of a 1-week history of blood in the urine and fatigue. He also has had a 5.0-kg (11-lb) weight loss during the past month. Physical examination shows pallor and cachexia. A nontender right flank mass is palpated. A CT scan of the chest, abdomen, and pelvis shows a 5-cm right upper pole renal mass and several pulmonary lesions. A biopsy specimen of an affected area of the lung is obtained. A photomicrograph of the biopsy specimen is shown. Molecular evaluation of the specimen is most likely to show which of the following genetic changes?", "answer": "VHL gene deletion", "options": {"A": "NF1 gene inactivation", "B": "PKD1 gene mutation", "C": "VHL gene deletion", "D": "TSC1 gene insertion", "E": "WT1 gene deletion"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old man is brought to the emergency department by his daughter because he was found to have decreased alertness that has gotten progressively worse. Three weeks ago he was diagnosed with an infection and given an antibiotic, though his daughter does not remember what drug was prescribed. His medical history is also significant for benign prostatic hyperplasia and hypertension, for which he was prescribed tamsulosin, a thiazide, and an ACE inhibitor. He has not sustained any trauma recently, and no wounds are apparent. On presentation, he is found to be confused. Labs are obtained with the following results:\n\nSerum:\nNa+: 135 mEq/L\nBUN: 52 mg/dL\nCreatinine: 2.1 mg/dL\n\nUrine:\nOsmolality: 548 mOsm/kg\nNa+: 13 mEq/L\nCreatinine: 32 mg/dL\n\nWhich of the following etiologies would be most likely given this patient's presentation?", "answer": "Overdiuresis by thiazides", "options": {"A": "Allergic reaction to antibiotic", "B": "Forgetting to take tamsulosin", "C": "Hemorrhage", "D": "Overdiuresis by thiazides", "E": "Toxic reaction to antibiotic"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Steroid hormone synthesis, lipid synthesis, and chemical detoxification are activities of which of the following?", "answer": "Smooth Endoplasmic Reticulum", "options": {"A": "Rough Endoplasmic Reticulum", "B": "Golgi bodies", "C": "Peroxisomes", "D": "Smooth Endoplasmic Reticulum", "E": "Nucleolus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old woman presents to the emergency department due to progressive shortness of breath and a dry cough for the past week. She notes that her symptoms are exacerbated by physical activity and relieved by rest. The woman was diagnosed with chronic kidney disease 2 years ago and was recently started on regular dialysis treatment. Her pulse rate is 105/min, blood pressure is 110/70 mm Hg, respiratory rate is 30/min, and temperature is 37.8°C (100.0°F). On examination of the respiratory system, there is dullness on percussion, decreased vocal tactile fremitus, and decreased breath sounds over the right lung base. The rest of the physical exam is within normal limits. Which of the following is the most likely cause of this patient’s symptoms?", "answer": "Pleural effusion", "options": {"A": "Primary spontaneous pneumothorax (PSP)", "B": "Pleural effusion", "C": "Pulmonary tuberculosis (TB)", "D": "Pneumonia", "E": "Acute bronchitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old female is brought to the emergency department by her roommate with a one day history of fever and malaise. She did not feel well after class the previous night and has been in her room since then. She has not been eating or drinking due to severe nausea. Her roommate checked on her one hour ago and was alarmed to find a fever of 102°F (38.9°C). On physical exam temperature is 103°F (40°C), blood pressure is 110/66 mmHg, pulse is 110/min, respirations are 23/min, and pulse oximetry is 98% on room air. She refuses to move her neck and has a rash on her trunk. You perform a lumbar puncture and the CSF analysis is shown below.\n\nAppearance: Cloudy\nOpening pressure: 180 mm H2O\nWBC count: 150 cells/µL (93% PMN)\nGlucose level: < 40 mg/dL\nProtein level: 50 mg/dL\nGram stain: gram-negative diplococci\n\nBased on this patient's clinical presentation, which of the following should most likely be administered?", "answer": "Ceftriaxone", "options": {"A": "Ceftriaxone", "B": "Rifampin", "C": "Erythromycin", "D": "Acyclovir", "E": "Dexamethasone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man is brought to the emergency department because of a fall that occurred while he was taking a shower earlier that morning. His wife heard him fall and entered the bathroom to find all four of his extremities twitching. The episode lasted approximately 30 seconds. He was unsure of what had happened and was unable to answer simple questions on awakening. He has regained orientation since that time. He has hypertension and hyperlipidemia. Current medications include metoprolol and atorvastatin. His temperature is 37.1°C (98.8°F), pulse is 72/min, respirations are 19/min, and blood pressures is 130/80 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Cranial nerve examination shows no abnormalities. He has 5/5 strength in all extremities. Examination shows full muscle strength. Sensation to pinprick, light touch, and vibration is normal and symmetrical. A noncontrast head CT is performed and shows a slightly hyperdense mass. Follow-up MRI shows a homogeneous, well-circumscribed 4-cm mass with compression of the adjacent white matter, and a hyperintense rim around the mass on T2 weighted imaging. Which of the following is the most likely diagnosis?", "answer": "Meningioma", "options": {"A": "Glioblastoma multiforme", "B": "Oligodendroglioma", "C": "Schwannoma", "D": "Hemangioblastoma", "E": "Meningioma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 48-year-old woman comes to the physician because of a 6-month history of excessive fatigue and a 1-month history of progressively increasing generalized pruritus. She has hypothyroidism, for which she receives thyroid replacement therapy. Physical examination shows jaundice. The liver is palpated 4 cm below the right costal margin. Serum studies show a direct bilirubin concentration of 2.9 mg/dL, alkaline phosphatase activity of 580 U/L, and increased titers of antimitochondrial antibodies and anti-thyroid peroxidase antibodies. Which of the following is the most likely cause of this patient's condition?", "answer": "Destruction of intrahepatic bile ducts", "options": {"A": "Idiopathic hepatocellular accumulation of fat", "B": "Neoplasia of the ampulla of Vater", "C": "Destruction of intrahepatic bile ducts", "D": "Autoimmune-mediated destruction of hepatocytes", "E": "Inflammation and fibrosis of the biliary tree"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old woman presents to her primary care physician with joint pain. She reports a 6-month history of progressive pain in her hands that is worse around her knuckles. The pain is symmetric bilaterally and seems to improve after she starts working in the morning at her job in a local grocery store. She has also lost 10 pounds over the past 6 months despite no changes in her weight or exercise regimen. Her past medical history is notable for seasonal allergies, hypertension, and intermittent constipation. She takes losartan and a laxative as needed. She had adolescent idiopathic scoliosis as a child and underwent a spinal fusion at the age of 14. She does not smoke or drink alcohol. Her temperature is 98.6°F (37°C), blood pressure is 135/75 mmHg, pulse is 92/min, and respirations are 16/min. On examination, she appears well and is appropriately interactive. Strength is 5/5 and sensation to light touch is intact in the bilateral upper and lower extremities. An examination of her hands demonstrates symmetric swelling of the metacarpophalangeal joints bilaterally. This patient’s condition is most strongly characterized by which of the following?", "answer": "HLA-DR4", "options": {"A": "HLA-B27", "B": "HLA-B8", "C": "HLA-DR2", "D": "HLA-DR3", "E": "HLA-DR4"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3100-g (6.9-lb) male newborn is brought to the emergency department by his mother because of fever and irritability. The newborn was delivered at home 15 hours ago. He was born at 39 weeks' gestation. The mother's last prenatal visit was at the beginning of the first trimester. She received all standard immunizations upon immigrating from Mexico two years ago. Seven weeks ago, she experienced an episode of painful, itching genital vesicles, which resolved spontaneously. Four hours before going into labor she noticed a gush of blood-tinged fluid from her vagina. The newborn is ill-appearing and lethargic. His temperature is 39.9°C (103.8°F), pulse is 170/min, respirations are 60/min, and blood pressure is 70/45 mm Hg. His skin is mildly icteric. Expiratory grunting is heard on auscultation. Skin turgor and muscle tone are decreased. Laboratory studies show:\nHemoglobin 15 g/dL\nLeukocyte count 33,800/mm3\nPlatelet count 100,000/mm3\nSerum glucose 55 mg/dL\nWhich of the following is the most likely causal organism?\"", "answer": "Streptococcus agalactiae", "options": {"A": "Staphylocccus aureus", "B": "Clostridium botulinum", "C": "Staphylococcus epidermidis", "D": "Neisseria meningitidis", "E": "Streptococcus agalactiae"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 10-year-old boy is brought in by his parents with increasing breathlessness. He was diagnosed with asthma about 2 years ago and has been on treatment since then. He was initially observed to have breathlessness, cough and chest tightness 2 or 3 times a week. He would wake up once or twice a month in the nighttime with breathlessness. At that time, his pediatrician started him on a Ventolin inhaler to be used during these episodes. His symptoms were well controlled until a few months ago when he started to experience increased nighttime awakenings due to breathlessness. He is unable to play outside with his friends as much because he gets winded easily and has to use his inhaler almost daily to help him breathe easier. He is able to walk and perform other routine activities without difficulty, but playing or participating in sports causes significant struggles. Based on his symptoms, his pediatrician adds an inhaled formoterol and budesonide combination to his current regime. During spirometry, which of the following peak expiratory flow rates will most likely be observed in this patient?", "answer": "65%", "options": {"A": "40%", "B": "55%", "C": "65%", "D": "85%", "E": "90%"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl is brought to the physician by her mother because she has not had her menstrual period yet. At birth, she had ambiguous genitalia. The mother reports that during the pregnancy she had noticed abnormal hair growth on her chin. A year ago, the girl broke her distal radius after a minor trauma. She is at the 95th percentile for height and 50th percentile for weight. Physical examination shows nodulocystic acne on the face, chest, and upper back. Breast development is at Tanner stage I. Pelvic examination reveals normal pubic hair with clitoromegaly. A pelvic ultrasound shows ovaries with multiple cysts and a normal uterus. Which of the following is the most likely diagnosis?", "answer": "Aromatase deficiency", "options": {"A": "Aromatase deficiency", "B": "Kallmann syndrome", "C": "Congenital adrenal hyperplasia", "D": "Mullerian agenesis", "E": "Polycystic ovary syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old woman is referred to a plastic surgeon for breast reconstruction approximately 18 months after undergoing right modified radical mastectomy for breast cancer. Physical exam demonstrates atrophy of the lower lateral pectoralis major muscle. Damage to which of the following nerves during mastectomy is the most likely cause of her atrophy?", "answer": "Medial pectoral", "options": {"A": "Long thoracic", "B": "Intercostobrachial", "C": "Medial pectoral", "D": "Lateral pectoral", "E": "Lateral intercostal"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-year-old boy is brought to the physician in December for episodic shortness of breath and a nonproductive cough for 3 months. These episodes frequently occur before sleeping, and he occasionally wakes up because of difficulty breathing. His mother also reports that he became short of breath while playing with his friends at daycare on several occasions. He is allergic to peanuts. He is at the 55th percentile for height and weight. Vital signs are within normal limits. Examination shows mild scattered wheezing in the thorax. An x-ray of the chest shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Asthma", "options": {"A": "Cystic fibrosis", "B": "Asthma", "C": "Cardiac failure", "D": "Primary ciliary dyskinesia", "E": "Tracheomalacia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying membranous transport proteins in striated muscle fibers of an experimental animal. An electrode is inserted into the gluteus maximus muscle and a low voltage current is applied. In response to this, calcium is released from the sarcoplasmic reticulum of the muscle fibers and binds to troponin C, which results in a conformational change of tropomyosin and unblocking of the myosin-binding site. The membranous transport mechanism underlying the release of calcium into the cytosol most resembles which of the following processes?", "answer": "Uptake of fructose by small intestinal enterocytes", "options": {"A": "Reabsorption of glucose by renal tubular cells", "B": "Secretion of doxorubicin from dysplastic colonic cells", "C": "Uptake of fructose by small intestinal enterocytes", "D": "Removal of calcium from cardiac myocytes", "E": "Absorption of LDL-cholesterol by hepatocytes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old boy is brought to the emergency room lapsing in and out of consciousness. The mother reports that 30 minutes ago, the young boy was found exiting the garage severely confused. A container of freshly spilled antifreeze was found on the garage floor. The next appropriate step would be to administer:", "answer": "Fomepizole", "options": {"A": "Dimercaprol", "B": "N-acetylcysteine", "C": "Ammonium chloride", "D": "Flumazenil", "E": "Fomepizole"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 39-year-old man comes to the emergency department because of a 2-day history of fever, chills, dyspnea, and a non-bloody productive cough. He was diagnosed with HIV infection 4 years ago and has been on highly active antiretroviral therapy since then. His temperature is 38.8°C (101.8°F). Examination shows crackles over the left lower lung base. His CD4+ T-lymphocyte count is 520/mm3 (N ≥ 500). An x-ray of the chest shows an infiltrate in the left lower lobe. Sputum cultures grow colonies with a narrow zone of green hemolysis without clearing on blood agar. The most likely causal pathogen of this patient's condition produces which of the following virulence factors?", "answer": "Polysaccharide capsule", "options": {"A": "M protein", "B": "Lipopolysaccharide", "C": "Type III secretion system", "D": "Polysaccharide capsule", "E": "Protein A"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old woman, gravida 3, para 2, at 12 weeks' gestation comes to her obstetrician for a prenatal visit. Screening tests in the first trimester showed a decreased level of pregnancy-associated plasma protein and an increased level of β-hCG. A genetic disorder is suspected. Which of the following results from an additional diagnostic test is most likely to confirm the diagnosis?", "answer": "Additional chromosome in placental tissue", "options": {"A": "Increased nuchal translucency on ultrasound", "B": "Additional chromosome in placental tissue", "C": "Decreased estriol in maternal serum", "D": "Triploidy in amniotic fluid", "E": "Decreased inhibin A in maternal serum"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 82-year-old woman is brought to the emergency department from a retirement community after she was found down during the evening. On presentation, she complains that she experienced several hours of nausea, vomiting, crampy abdominal pain, and diarrhea prior to blacking out. She said that she cannot recall any factors that may have triggered her symptoms; however, she recalls that some of her friends with whom she eats also had similar symptoms earlier in the day and were brought to the hospital. They often go for walks and occasionally cook for themselves from a garden that they keep in the woods behind the facility. One of the residents on the team recalls seeing other patients from this facility earlier today, one of whom presented with kidney failure and scleral icterus prior to passing away. The enzyme most likely affected in this case has which of the following functions?", "answer": "Synthesis of small nucleolar RNA", "options": {"A": "Synthesis of 5S ribosomal RNA", "B": "Synthesis of large ribosomal RNA", "C": "Synthesis of small nucleolar RNA", "D": "Synthesis of small ribosomal RNA", "E": "Synthesis of transfer RNA"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-month-old boy presents with decreased growth, pigmented retinopathy, hemolytic anemia, and peripheral neuropathy. You suspect that these signs are the result of a vitamin deficiency leading to increased fatty acid oxidation. Which of the following is most likely responsible for this patient's symptoms?", "answer": "Abetalipoproteinemia", "options": {"A": "Pernicious anemia", "B": "Abetalipoproteinemia", "C": "Goat milk ingestion", "D": "Hartnup disease", "E": "Excessive boiling of formula"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old boy is brought to the emergency department after his mother noticed maroon-colored stools in his diaper. He has not had any diarrhea or vomiting. The prenatal and birth histories are unremarkable, and he has had no recent trauma. He tolerates solid foods well. The vital signs include: temperature 37.0℃ (98.6℉), blood pressure 90/60 mm Hg, pulse 102/min, and respiratory rate 16/min. The weight is at the 50th percentile. The examination revealed an alert boy with pallor. The abdomen was mildly tender at the right iliac region without masses. There were no anal fissures or hemorrhoids. A stool guaiac test was positive. The laboratory results are as follows:\nComplete blood count (CBC)\nLeukocytes 7,500/uL\nHemoglobin 9 g/dL\nHematocrit 24%\nPlatelets 200,000/uL\nWhich of the following is the most appropriate next step in the management of this patient?", "answer": "Technetium-99m pertechnetate scan", "options": {"A": "Stool culture and leukocytes", "B": "Elimination of cow’s milk from the diet", "C": "Colonoscopy", "D": "Technetium-99m pertechnetate scan", "E": "Abdominal ultrasound"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 14-year-old boy presents to his pediatrician with weakness and frequent episodes of dizziness. He had chronic mucocutaneous candidiasis when he was 4 years old and was diagnosed with autoimmune hypoparathyroidism at age 8. On physical examination, his blood pressure is 118/70 mm Hg in the supine position and 96/64 mm Hg in the upright position. Hyperpigmentation is present over many areas of his body, most prominently over the extensor surfaces, elbows, and knuckles. His laboratory evaluation suggests the presence of antibodies to 21-hydroxylase and a mutation in the AIRE (autoimmune regulator) gene. The pediatrician explains to his parents that his condition is due to the failure of immunological tolerance. Which of the following mechanisms is most likely to have failed in the child?", "answer": "Negative selection", "options": {"A": "Positive selection", "B": "Negative selection", "C": "Anergy", "D": "Inhibition of the inactivation of harmful lymphocytes by regulatory T cells", "E": "Deletion of mature lymphocytes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 71-year old man is brought to the emergency department because of progressively worsening shortness of breath and fatigue for 3 days. During the last month, he has also noticed dark colored urine. He had an upper respiratory infection 6 weeks ago. He underwent a cholecystectomy at the age of 30 years. He has hypertension, hyperlipidemia, and type 2 diabetes mellitus. He immigrated to the US from Italy 50 years ago. Current medications include simvastatin, lisinopril, and metformin. He appears pale. His temperature is 37.1°C (98.8°F), pulse is 96/min, respirations are 21/min, and blood pressure is 150/80 mm Hg. Auscultation of the heart shows a grade 4/6 systolic murmur over the right second intercostal space that radiates to the carotids. Laboratory studies show:\nLeukocyte count 9,000/mm3\nHemoglobin 8.3 g/dL\nHematocrit 24%\nPlatelet count 180,000/mm3\nLDH 212 U/L\nHaptoglobin 15 mg/dL (N=41–165)\nSerum\nNa+ 138 mEq/L\nK+ 4.5 mEq/L\nCL- 102 mEq/L\nHCO3- 24 mEq/L\nUrea nitrogen 20 mg/dL\nCreatinine 1.2 mg/dL\nTotal bilirubin 1.8 mg/dL\nStool testing for occult blood is negative. Direct Coombs test is negative. Echocardiography shows an aortic jet velocity of 4.2 m/s and a mean pressure gradient of 46 mm Hg. Which of the following is the most appropriate next step in management to treat this patient's anemia?\"", "answer": "Aortic valve replacement", "options": {"A": "Administration of corticosteroids", "B": "Administration of hydroxyurea", "C": "Supplementation with iron", "D": "Aortic valve replacement", "E": "Discontinuation of medication\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man with gastroesophageal reflux disease and osteoarthritis is brought to the emergency department because of a 1-hour history of severe, stabbing epigastric pain. For the last 6 months, he has had progressively worsening right knee pain, for which he takes ibuprofen several times a day. He has smoked half a pack of cigarettes daily for 25 years. The lungs are clear to auscultation. An ECG shows sinus tachycardia without ST-segment elevations or depressions. This patient is most likely to have referred pain in which of the following locations?", "answer": "Left shoulder", "options": {"A": "Right scapula", "B": "Left shoulder", "C": "Umbilicus", "D": "Left jaw", "E": "Right groin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 57-year-old woman comes to the physician because of a 2-week history of swelling of both her feet. It improves a little bit with elevation but is still bothersome to her because her shoes no longer fit. She has type 2 diabetes mellitus treated with metformin and linagliptin. She was diagnosed with hypertension 6 months ago and started treatment with amlodipine. Subsequent blood pressure measurements on separate occasions have been around 130/90 mm Hg. She otherwise feels well. Today, her pulse is 80/min, respirations are 12/min, and blood pressure is 132/88 mm Hg. Cardiovascular examination shows no abnormalities. There is pitting edema of both ankles. Which of the following would have been most likely to reduce the risk of edema in this patient?", "answer": "Addition of enalapril", "options": {"A": "Addition of enalapril", "B": "Addition of chlorpheniramine", "C": "Addition of furosemide", "D": "Use of compression stockings", "E": "Use of nifedipine instead"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 50-year-old woman comes to the physician for the evaluation of excessive hair growth on her chin over the past 2 weeks. She also reports progressive enlargement of her gums. Three months ago, she underwent a liver transplantation due to Wilson disease. Following the procedure, the patient was started on transplant rejection prophylaxis. She has a history of poorly-controlled type 2 diabetes mellitus. Temperature is 37°C (98.6°F), pulse is 80/min, respirations are 22/min, and blood pressure is 150/80 mm Hg. Physical examination shows dark-pigmented, coarse hair on the chin, upper lip, and chest. The gingiva and the labial mucosa are swollen. There is a well-healed scar on her right lower abdomen. Which of the following drugs is the most likely cause of this patient's findings?", "answer": "Cyclosporine", "options": {"A": "Daclizumab", "B": "Cyclosporine", "C": "Sirolimus", "D": "Tacrolimus", "E": "Methotrexate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old man presents to the clinic with the complaint of a new rash. The lesions are not bothersome, but he is worried as he has never seen anything like this on his body. Upon further questioning the patient states has been generally healthy except for a one time \"horrible\" flu-like episode two months ago in June. He has since gotten better. On physical exam the following rash is observed (Figure 1). What is the cause of this patient's rash?", "answer": "Molluscum contagiosum virus", "options": {"A": "Staphylococcus aureus cellulitis", "B": "Molluscum contagiosum virus", "C": "Human immunodeficiency virus (HIV)", "D": "Human papilloma virus (HPV)", "E": "Varicella zoster virus (VZV)"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An HIV-positive 48-year-old man comes to the emergency department because of a 3-month history of recurrent, painful mouth ulcers. This time, the pain is so severe that the patient cannot eat. He has a history of a seizure disorder but currently does not take any medications. He appears very ill. His temperature is 39.0°C (102.2°F). Physical examination shows numerous vesicular ulcerations on the lips and sloughing of the gums, buccal mucosa, and hard palate. Genetic analysis of the pathogen isolated from the lesions shows a mutation in a gene encoding viral phosphotransferases. Which of the following drugs is the most appropriate treatment?", "answer": "Cidofovir", "options": {"A": "Foscarnet", "B": "Acyclovir", "C": "Cidofovir", "D": "Ganciclovir", "E": "Famciclovir"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman presents to an outpatient clinic for a routine gynecologic examination. She is concerned about some swelling on the right side of her vagina. She senses that the right side is larger than the left and complains that sometimes that area itches and there is a dull ache. She denies any recent travel or history of trauma. She mentions that she is sexually active in a monogamous relationship with her husband; they use condoms inconsistently. On physical examination her vital signs are normal. Examination of the pelvic area reveals a soft, non-tender, mobile mass that measures approximately 2 cm in the greatest dimension at the 8 o’clock position on the right side of the vulva, just below the vaginal wall. Which of the following is the most likely diagnosis?", "answer": "Bartholin duct cyst", "options": {"A": "Condylomata acuminata", "B": "Bartholin duct cyst", "C": "Vulvar hematoma", "D": "Molluscum contagiosum", "E": "Squamous cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 64-year-old woman presents to the physician’s office to find out the results of her recent abdominal CT. She had been complaining of fatigue, weight loss, and jaundice for 6 months prior to seeing the physician. The patient has a significant medical history of hypothyroidism, generalized anxiety disorder, and hyperlipidemia. She takes levothyroxine, sertraline, and atorvastatin. The vital signs are stable today. On physical examination, her skin shows slight jaundice, but no scleral icterus is present. The palpation of the abdomen reveals no tenderness, guarding, or masses. The CT results shows a 3 x 3 cm mass located at the head of the pancreas. Which of the following choices is most appropriate for delivering bad news to the patient?", "answer": "Set aside an appropriate amount of time in your schedule, and ensure you will not have any interruptions as you explain the bad news to the patient", "options": {"A": "Set aside an appropriate amount of time in your schedule, and ensure you will not have any interruptions as you explain the bad news to the patient", "B": "Ask that a spouse or close relative come to the appointment, explain to them the bad news, and see if they will tell the patient since they have a closer relationship", "C": "Call the patient over the phone to break the bad news, and tell them they can make an office visit if they prefer", "D": "Train one of the nursing staff employees on this matter, and delegate this duty as one of their job responsibilities", "E": "Refer the patient to an oncologist without informing the patient of their cancer"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator studying DNA replication in Campylobacter jejuni inoculates a strain of this organism into a growth medium that contains radiolabeled thymine. After 2 hours, the rate of incorporation of radiolabeled thymine is measured as a proxy for the rate of DNA replication. The cells are then collected by centrifugation and suspended in a new growth medium that contains no free uracil. After another 2 hours, the rate of incorporation of radiolabeled thymine is measured again. The new growth medium directly affects the function of which of the following enzymes?", "answer": "Primase", "options": {"A": "Telomerase", "B": "DNA polymerase I", "C": "DNA polymerase II", "D": "Ligase", "E": "Primase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 22-year-old woman presents to the emergency department feeling lightheaded and states that her heart is racing. She does not have a history of any chronic medical conditions. She is a college sophomore and plays club volleyball. Although she feels stressed about her upcoming final exams next week, she limits her caffeine intake to 3 cups of coffee per day to get a good night sleep. She notes that her brother takes medication for some type of heart condition, but she does not know the name of it. Both her parents are alive and well. She denies recent illness, injuries, or use of cigarettes, alcohol, or recreational drugs. The pertinent negatives from the review of systems include an absence of fever, nausea, vomiting, sweating, fatigue, or change in bowel habits. The vital signs include: temperature 36.8°C (98.2°F), heart rate 125/min, respiratory rate 15/min, blood pressure 90/75 mm Hg, and oxygen saturation of 100% on room air. The laboratory results are within normal limits. The ECG is significant for a shortened PR interval and widened QRS. Which of the following medications should the patient avoid in this scenario?", "answer": "Verapamil", "options": {"A": "Procainamide", "B": "Verapamil", "C": "Ablation", "D": "Synchronized cardioversion", "E": "Amlodipine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 13-year-old boy is brought to the physician because of a 4-month history of worsening dizziness, nausea, and feeling clumsy. An MRI of the brain shows a well-demarcated, 4-cm cystic mass in the posterior fossa. The patient undergoes complete surgical resection of the mass. Pathologic examination of the surgical specimen shows parallel bundles of cells with eosinophilic, corkscrew-like processes. Which of the following is the most likely diagnosis?", "answer": "Pilocytic astrocytoma", "options": {"A": "Medulloblastoma", "B": "Ependymoma", "C": "Pilocytic astrocytoma", "D": "Craniopharyngioma", "E": "Pinealoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old man comes to the physician for a 2-day history of headache and breathlessness on exertion. During the same period, he has vomited twice and not passed urine. He also reports pain and stiffness in his fingers that has worsened progressively over the past 2 years. He has no history of serious illness and takes no medications. He does not smoke or drink alcohol. He is in moderate distress. His temperature is 37.2°C (98.9°F), pulse is 88/min, blood pressure is 170/100 mm Hg, and respirations are 24/min. Pulse oximetry on room air shows an oxygen saturation of 91%. Examination reveals pallor, 2+ pretibial edema, and jugular venous distention. The skin on the arms, chest, and upper back is coarse and thickened. Diffuse cutaneous hyperpigmentation and hypopigmented patches with perifollicular hypopigmentation are noted. Contractures are present in the proximal interphalangeal joints of both hands. Diffuse crackles are heard on auscultation of the chest. There is dullness to percussion and decreased breath sounds over both lung bases. S1 and S2 are normal. An S3 gallop is heard at the apex. The remainder of the examination shows no abnormalities. His hemoglobin concentration is 8.1 g/dL, and his serum creatinine is 5.3 mg/dL. Further evaluation of this patient is most likely to show which of the following?", "answer": "Decreased serum haptoglobin levels", "options": {"A": "Increased anticentromere antibody titers", "B": "Decreased serum haptoglobin levels", "C": "Decreased serum complement levels", "D": "Increased total iron binding capacity", "E": "Increased anti-CCP antibody titers\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old woman presents to the emergency department complaining of fever, worsening fatigue, and muscle weakness for the previous 48 hours. The patient describes her muscle weakness as symmetric and worse in the upper limbs. Her past medical history is significant for long-standing diabetes type 2 complicated by stage 5 chronic kidney disease (CKD) on hemodialysis. She takes lisinopril, verapamil, metformin, and glargine. Today, the patient’s vital signs include: temperature 38.6°C (101.5°F), pulse 80/min, blood pressure 155/89 mm Hg, respirations 24/min, and 95% oxygen saturation on room air. The cardiac and pulmonary exams are unremarkable. The abdomen is soft and non-tender. Her strength is 3/5 in the upper extremities and 4/5 in the lower extremities and her sensation is intact. Deep tendon reflexes are absent in both the upper and lower limbs. A 12-lead electrocardiogram (ECG) is shown in the image below. Blood work is drawn and the patient is admitted and started on continuous cardiac monitoring. Based on the available information, what is the next best step in managing this patient?", "answer": "Administer IV calcium gluconate", "options": {"A": "Administer IV calcium gluconate", "B": "Order a stat serum potassium level", "C": "Emergency dialysis", "D": "Administer regular insulin and 50% dextrose in water", "E": "Administer IV sodium bicarbonate"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 71-year-old man with recently diagnosed small-cell lung cancer sees his physician because of increasing weakness over the past 3 months. He is unable to climb stairs or comb his hair. His weakness is worse after inactivity and improves with exercise. He is a former smoker with a 30-pack-year history. He is currently preparing for initiation of chemotherapy. His vital signs are within normal limits. On examination, ptosis of both eyelids is seen. Dry oral mucosa is notable. Significant weakness is detected in all four proximal extremities. The patellar and biceps reflexes are absent. Auscultation of the lungs reveals generalized wheezing and rhonchi. Which of the following is the most likely underlying mechanism for this patient’s weakness?", "answer": "Autoantibody-impaired acetylcholine release from nerve terminals", "options": {"A": "Acute autoimmune demyelination of axons", "B": "Autoantibody-impaired acetylcholine release from nerve terminals", "C": "Endomysial CD8+ T cell infiltration with vacuoles and inclusion bodies", "D": "Necrotizing vasculitis with granuloma formation", "E": "Reduced number of available postsynaptic acetylcholine receptors"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old man is brought to the emergency department for increasing colicky lower abdominal pain and distention for 4 days. He has nausea. He has not passed flatus for the past 2 days. His last bowel movement was 4 days ago. He has hypertension, type 2 diabetes mellitus, and left hemiplegia due to a cerebral infarction that occurred 2 years ago. His current medications include aspirin, atorvastatin, hydrochlorothiazide, enalapril, and insulin. His temperature is 37.3°C (99.1°F), pulse is 90/min, and blood pressure is 126/84 mm Hg. Examination shows a distended and tympanitic abdomen. There is mild tenderness to palpation over the lower abdomen. Bowel sounds are decreased. Digital rectal examination shows an empty rectum. Muscle strength is decreased in the left upper and lower extremities. Deep tendon reflexes are 3+ on the left and 2+ on the right. The remainder of the examination shows no abnormalities. Laboratory studies are within normal limits. An x-ray of the abdomen in left lateral decubitus position is shown. The patient is kept nil per os and a nasogastric tube is inserted. Intravenous fluids are administered. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Endoscopic detorsion", "options": {"A": "Metoclopramide therapy", "B": "Endoscopic detorsion", "C": "Intravenous antibiotic therapy", "D": "Colonoscopy", "E": "Rectal tube insertion"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old woman, gravida 2, para 1, at 38 weeks' gestation comes to the emergency department in active labor. She received all of her prenatal care for this pregnancy. Pregnancy and delivery of her first child were uncomplicated. The patient's blood type is Rh-negative. Four hours after arrival, a healthy 3650-g (8-lb) female newborn is delivered. Delivery of the fetus is followed by placental retention and heavy vaginal bleeding. One hour later, the placenta is manually removed and the bleeding ceases. The mother's temperature is 36.7°C (98.1°F), pulse is 90/min, and blood pressure is 110/60 mm Hg. Examination shows blood on the vulva, the introitus, and on the medial aspect of each thigh. The neonate's blood type is Rh-positive. A single dose of anti-D immune globulin is administered. Which of the following is the most appropriate next step in management?", "answer": "Perform rosette test", "options": {"A": "Perform flow cytometry", "B": "Perform rosette test", "C": "Perform Kleihauer-Betke test", "D": "Administer additional dose of anti-D immune globulin", "E": "Perform Coombs test"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 5-year-old boy is brought to the emergency department because of a generalized pruritic rash for 14 hours. Five days ago, he had pink eyes that resolved spontaneously. He has acute lymphoblastic leukemia. He has received 3 cycles of chemotherapy with vincristine, asparaginase, dexamethasone, and doxorubicin. His last treatment cycle was 2 weeks ago. The patient's other medications include multivitamin supplements. His temperature is 38°C (100.4°F), pulse 90/min, and blood pressure is 105/65 mm Hg. Examination of the skin shows multiple crops of macules and papules over the face, trunk, and extremities. There are also excoriation marks and crusted lesions. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in the treatment of this patient?", "answer": "Acyclovir administration", "options": {"A": "Vitamin A administration", "B": "Immunoglobulin administration", "C": "Symptomatic therapy", "D": "Acyclovir administration", "E": "Penicillin V administration"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old adolescent male is brought to the emergency department by fire and rescue after being struck by a moving vehicle. The patient reports that he was running through his neighborhood when a car struck him while turning right on a red light. He denies any loss of consciousness. His temperature is 99.0°F (37.2°C), blood pressure is 88/56 mmHg, pulse is 121/min, respirations are 12/min, and SpO2 is 95% on room air. The patient is alert and oriented to person, place and time and is complaining of pain in his abdomen. He has lacerations on his face and extremities. On cardiac exam, he is tachycardic with normal S1 and S2. His lungs are clear to auscultation bilaterally, and his abdomen is soft but diffusely tender to palpation. The patient tenses his abdomen when an abdominal exam is performed. Bowel sounds are present, and he is moving all 4 extremities spontaneously. His skin is cool with delayed capillary refill. After the primary survey, 2 large-bore IVs are placed, and the patient is given a bolus of 2 liters of normal saline.\n\nWhich of the following is the best next step in management?", "answer": "Focused Abdominal Sonography for Trauma (FAST) exam", "options": {"A": "Abdominal CT", "B": "Focused Abdominal Sonography for Trauma (FAST) exam", "C": "Diagnostic peritoneal lavage", "D": "Diagnostic laparoscopy", "E": "Emergency laparotomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is examining tissue samples from various muscle tissue throughout the body. She notices that biopsies collected from a specific site have a high concentration of sarcoplasmic reticulum, mitochondria, and myoglobin; they also stain poorly for ATPase. Additionally, the cell surface membranes of the myocytes in the specimen lack voltage-gated calcium channels. These myocytes are found in the greatest concentration at which of the following sites?", "answer": "Semispinalis muscle", "options": {"A": "Ventricular myocardium", "B": "Semispinalis muscle", "C": "Glandular myoepithelium", "D": "Tunica media", "E": "Lateral rectus muscle"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old woman comes to the physician for a 2-month history of urinary incontinence and a vaginal mass. She has a history of five full-term normal vaginal deliveries. She gave birth to a healthy newborn 2-months ago. Since then she has felt a sensation of vaginal fullness and a firm mass in the lower vagina. She has loss of urine when she coughs, sneezes, or exercises. Pelvic examination shows an irreducible pink globular mass protruding out of the vagina. A loss of integrity of which of the following ligaments is most likely involved in this patient's condition?", "answer": "Uterosacral ligament", "options": {"A": "Infundibulopelvic ligament", "B": "Uterosacral ligament", "C": "Cardinal ligament of the uterus", "D": "Broad ligament of the uterus", "E": "Round ligament of uterus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old woman presents to the emergency department with an acute exacerbation of her 3-month history of low back and right leg pain. She says she has had similar symptoms in the past, but this time the pain was so excruciating, it took her breath away. She describes the pain as severe, shock-like, and localized to her lower back and radiating straight down the back of her right thigh and to her calf, stopping at the ankle. Her pain is worse in the morning, and, sometimes, the pain wakes her up at night with severe buttock and posterior thigh pain but walking actually makes the pain subside somewhat. The patient reports no smoking history or alcohol or drug use. She has been working casually as a waitress and does find bending over tables a strain. She is afebrile, and her vital signs are within normal limits. On physical examination, her left straight leg raise test is severely limited and reproduces her buttock pain at 20° of hip flexion. Pain is worsened by the addition of ankle dorsiflexion. The sensation is intact. Her L4 and L5 reflexes are normal, but her S1 reflex is absent on the right side. A CT of the lumbar spine shows an L5–S1 disc protrusion with right S1 nerve root compression. Which of the following muscle-nerve complexes is involved in producing an S1 reflex?", "answer": "Gastrocnemius/soleus-tibial nerve", "options": {"A": "Tibialis posterior-tibial nerve", "B": "Quadriceps femoris-femoral nerve", "C": "Sartorius-femoral nerve", "D": "Adductors-obturator nerve", "E": "Gastrocnemius/soleus-tibial nerve"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old man comes to the physician because of a 2-week history of productive cough, weight loss, and intermittent fever. He recently returned from a 6-month medical deployment to Indonesia. He appears tired. Physical examination shows nontender, enlarged, palpable cervical lymph nodes. An x-ray of the chest shows right-sided hilar lymphadenopathy. A sputum smear shows acid-fast bacilli. A diagnosis of pulmonary tuberculosis is made from PCR testing of the sputum. The patient requests that the physician does not inform anyone of this diagnosis because he is worried about losing his job. Which of the following is the most appropriate initial action by the physician?", "answer": "Inform the local public health department of the diagnosis", "options": {"A": "Inform the local public health department of the diagnosis", "B": "Request the patient's permission to discuss the diagnosis with an infectious disease specialist", "C": "Assure the patient that his diagnosis will remain confidential", "D": "Confirm the diagnosis with a sputum culture", "E": "Notify all of the patient's household contacts of the diagnosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old African American woman presents to her family physician complaining of fevers, fatigue, weight loss, joint pains, night sweats and a rash on her face that extends over the bridge of her nose. She has also had multiple sores in her mouth over the past few weeks. She recently had a root canal procedure done without complications. She has no significant past medical history, but has recently had a urinary tract infection. She denies tobacco, alcohol, and illicit drug use. Laboratory evaluation reveals hemolytic anemia. If she were found to have a cardiac lesion, what would be the most likely pathogenetic cause?", "answer": "Immune complex deposition and subsequent inflammation", "options": {"A": "Bacteremia secondary to a recent dental procedure", "B": "Abberent flow causing platelet-fibrin thrombus formation secondary to hypercoagulability and malignancy.", "C": "Bacteremia secondary to a urinary tract infection", "D": "Immune complex deposition and subsequent inflammation", "E": "Left atrial mass causing a ball valve-type outflow obstruction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old woman comes to the physician for a follow-up examination. Two years ago, she was diagnosed with multiple sclerosis. Three weeks ago, she was admitted and treated for right lower leg weakness with high-dose methylprednisone for 5 days. She has had 4 exacerbations over the past 6 months. Current medications include interferon beta and a multivitamin. Her temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 116/74 mm Hg. Examination shows pallor of the right optic disk. Neurologic examination shows no focal findings. She is anxious about the number of exacerbations and repeated hospitalizations. She is counseled about the second-line treatment options available to her. She consents to treatment with natalizumab. However, she has read online about its adverse effects and is concerned. This patient is at increased risk for which of the following complications?", "answer": "Progressive multifocal leukoencephalopathy", "options": {"A": "Syndrome of inappropriate antidiuretic hormone", "B": "Progressive multifocal leukoencephalopathy", "C": "Parkinsonism", "D": "Tuberculosis", "E": "Aplastic anemia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 2-day-old male newborn is brought to the emergency department by his mother because of irritability and vomiting for two hours. During this period, he has vomited bilious fluid three times. He has not yet passed stool. The mother has breastfed the newborn every two hours. He has wet two diapers during the last two days. He was born at term and was delivered at home. Pregnancy and delivery were uncomplicated. The mother had no prenatal care during pregnancy. The patient currently weighs 3100 g (6 lb 13 oz) and is 50 cm (19.6 in) in length. The newborn appears restless. His temperature is 37.3°C (99.14°F), pulse is 166/min, respirations are 60/min, and blood pressure is 60/45 mm Hg. There is no redness or warmth around the umbilical cord stump. Cardiopulmonary examination shows no abnormalities. Bowel sounds are sparse. The abdomen is distended. Digital rectal examination shows no abnormalities. An x-ray of the abdomen with contrast shows dilated small bowel loops, a microcolon, a mixture of gas and meconium located in the right lower quadrant. A nasogastric tube is placed and fluid resuscitation is begun. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Gastrografin enema", "options": {"A": "Reassurance and follow-up in 2 weeks", "B": "Gastrografin enema", "C": "Exploratory laparotomy", "D": "Rectal suction biopsy", "E": "Colonoscopy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old woman comes to the physician for the evaluation of fatigue, poor appetite, and an unintentional 10-kg (22-lb) weight loss over the past 6 months. The patient also reports several episodes of nausea and two episodes of non-bloody vomiting. There is no personal or family history of serious illness. Menses occur at regular 27-day intervals and last 6 days. Her last menstrual period was 3 weeks ago. She is sexually active with her husband, but states that she has lost desire in sexual intercourse lately. Her temperature is 37°C (98.6°F), pulse is 100/min, and blood pressure is 96/70 mm Hg. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13.5 g/dL\nLeukocyte count 7,000/mm3\nSerum\nNa+ 128 mEq/L\nCl- 96 mEq/L\nK+ 5.8 mEq/L\nHCO3- 23 mEq/L\nGlucose 70 mg/dL\nAM Cortisol 2 μg/dL\nWhich of the following is the most appropriate next step in management?\"", "answer": "Cosyntropin administration\n\"", "options": {"A": "TSH measurement", "B": "Urine aldosterone level measurement", "C": "Hydrocortisone administration", "D": "Adrenal imaging", "E": "Cosyntropin administration\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old Caucasian male is stabbed in his left flank, injuring his left kidney. As the surgeon undertakes operative repair, she reviews relevant renal anatomy. All of the following are correct regarding the left kidney EXCEPT?", "answer": "The left kidney has a longer renal artery than the right kidney", "options": {"A": "The left kidney has a longer renal vein than the right kidney", "B": "The left kidney has a longer renal artery than the right kidney", "C": "The left kidney lies between T12 and L3", "D": "The left kidney underlies the left 12th rib", "E": "The left kidney moves vertically during deep breathing"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 82-year-old male with a history of congestive heart failure presented with new-onset atrial fibrillation. He was initially started on carvedilol, but he now requires an additional agent for rate control. He is started on a medicine and is warned by his physician of the following potential side effects associated with this therapy: nausea, vomiting, confusion, blurry yellow vision, electrolyte abnormalities, and potentially fatal arrhythmia. Which of the following is most likely to increase this patient's susceptibility to the toxic effects associated with this medication?", "answer": "Hypokalemia", "options": {"A": "Hyponatremia", "B": "Elevated AST and ALT", "C": "Hypokalemia", "D": "Increased GFR with normal creatinine", "E": "Hyperkalemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman with a psychiatric history of bipolar disorder is brought into the emergency department by emergency medical services. The patient is unconscious, but the mother states that she walked into the patient's room with the patient lying on the floor and an empty bottle of unknown pills next to her. The patient has previously tried to commit suicide 2 years ago. Upon presentation, the patient's vitals are HR 110, BP 105/60, T 99.5, RR 22. The patient soon has 5 episodes non-bilious non-bloody vomiting. Upon physical exam, she has pain in the right upper quadrant and her liver function tests are AST 1050 U/L, ALT 2050 U/L, ALP 55 U/L, Total Bilirubin 0.8 mg/dL, Direct Bilirubin 0.2 mg/dL. You are awaiting her toxicology screen. What is the most likely diagnosis?", "answer": "Acetaminophen ingestion", "options": {"A": "Beta-blocker ingestion", "B": "Acetaminophen ingestion", "C": "Tricyclic antidepressant ingestion", "D": "Opiate ingestion", "E": "Salicylate ingestion"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old woman presents into the clinic complaining of worsening malaise, hair loss, and a rash on her face. The patient states that she has been avoiding daylight because the rash becomes painful, and she has not been able to go to classes because of debilitating arthralgia in her fingers and ankles. No significant past medical history. She takes no medication. At the time of the consult, the patient has a fever of 39.0°C (102.2 °F). The presence of which of the following is most commonly seen on diagnostic labs in this patient’s most likely condition?", "answer": "Antinuclear antibody", "options": {"A": "Anti-smith antibody", "B": "Anti-dsDNA", "C": "Anti-histone antibody", "D": "Anti-Ro antibody", "E": "Antinuclear antibody"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old woman presents to your office with a serum glucose of 250 mg/dL and you diagnose diabetes mellitus type II. You intend to prescribe the patient metformin, but you decide to order laboratory tests before proceeding. Which of the following basic metabolic panel values would serve as a contraindication to the use of metformin?", "answer": "Creatinine > 2.0", "options": {"A": "K+ > 4.0", "B": "Na+ > 140", "C": "HCO3- > 30", "D": "Glucose > 300", "E": "Creatinine > 2.0"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "You are reading through a recent article that reports significant decreases in all-cause mortality for patients with malignant melanoma following treatment with a novel biological infusion. Which of the following choices refers to the probability that a study will find a statistically significant difference when one truly does exist?", "answer": "Power", "options": {"A": "Type I error", "B": "Type II error", "C": "Power", "D": "Confidence interval", "E": "p-value"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl comes to the physician because of a 2-day history of pain in her right knee. Last week she had right wrist pain. She has no history of recent trauma. She returned from summer camp in Connecticut 2 weeks ago. She is sexually active with one male partner and uses an oral contraceptive. Her temperature is 38°C (100.4°F). Examination shows several painless vesiculopustular lesions on the back and one lesion on the right sole of the foot. There is swelling of the right knee with tenderness to palpation. Passive extension of the right wrist and fingers elicits pain. Which of the following is the most likely diagnosis?", "answer": "Disseminated gonococcal infection", "options": {"A": "Reactive arthritis", "B": "Staphylococcus aureus arthritis", "C": "Systemic lupus erythematosus", "D": "Disseminated gonococcal infection", "E": "Acute rheumatic fever"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old man comes to the physician because of an 8-hour history of painful leg cramping, runny nose, chills, diarrhea, and abdominal pain. Examination shows cool, damp skin with piloerection. The pupils are 7 mm in diameter and equal in size. Deep tendon reflexes are 3+ bilaterally. The diagnosis of opioid withdrawal is made. After the patient is stabilized, the physician initiates a withdrawal regimen with methadone. Which of the following characteristics makes this drug a suitable substance for the treatment of this patient's addiction?", "answer": "Long elimination half-life", "options": {"A": "Low dependence risk", "B": "Rapid onset of action", "C": "Limited potency", "D": "Long elimination half-life", "E": "Low tolerance potential"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man presents with intense pain in his left knee that started after returning from a camping trip 2 days ago, during which he consumed copious amounts of alcohol and red meat. He says he has had similar episodes in the past that resolved spontaneously usually over a period of about 10 days. His past medical history is significant for essential hypertension managed with hydrochlorothiazide 20 mg/day. The patient is afebrile, and his vital signs are within normal limits. Physical examination shows edema, warmth, and erythema of the left knee, which is also severely tender to palpation; The range of motion at the left knee joint is limited. A joint arthrocentesis of the left knee is performed, and synovial fluid analysis reveals 20,000 neutrophils and the following image is seen under polarized light microscopy (see image). Which of the following is the best course of treatment for this patient’s condition?", "answer": "Nonsteroidal antiinflammatory drugs", "options": {"A": "Colchicine", "B": "Nonsteroidal antiinflammatory drugs", "C": "Uricosuric drug", "D": "Intra-articular steroid injection", "E": "Xanthine oxidase inhibitor"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 9-month-old male infant is brought to his pediatrician by his mother with lethargy and decreased oral intake for one day. His mother also mentions that he did not sleep well the previous night. A review of the medical record reveals several missed appointments and that the boy was born at 36 weeks gestation via spontaneous vaginal delivery. At the clinic, his temperature is 37.2ºC (99.0ºF), pulse rate is 140/minute, respirations are 44/minute, and blood pressure is 92/60 mm Hg. On physical exam the infant is awake but irritable and the rest of the physical is within normal limits for his age. On ophthalmologic examination, there are multiple retinal hemorrhages that extend to the periphery in both eyes. Which of the following investigations is most likely to be helpful in the management of the infant?", "answer": "Noncontrast computed tomography of head", "options": {"A": "Hemoglobin electrophoresis", "B": "Peripheral blood smear", "C": "Noncontrast computed tomography of head", "D": "Lumbar puncture", "E": "Bone marrow aspiration"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 21-year-old girl with a history of bipolar disorder, now in a depressive episode, presents to the emergency in distress. She reports that she wanted to \"end it all\" and swallowed a full bottle of acetaminophen. However, regretting what it would do to her parents, and she decided that she wants to live. She appears in no acute distress and clearly states she swallowed the pills one hour ago. What is the most appropriate next step in management?", "answer": "Give activated charcoal and draw a serum acetaminophen level in three hours", "options": {"A": "Give activated charcoal and draw a serum acetaminophen level now", "B": "Give activated charcoal and draw a serum acetaminophen level in three hours", "C": "Give activated charcoal and test the urine for an acetaminophen level", "D": "Draw a serum acetaminophen level now", "E": "Give activated charcoal and draw a serum acetaminophen in two hours"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-year-old boy presents to an urgent care clinic from his friend’s birthday party after experiencing trouble breathing. His father explains that the patient had eaten peanut butter at the party, and soon after, he developed facial flushing and began scratching his face and neck. This has never happened before but his father says that they have avoided peanuts and peanut butter in the past because they were worried about their son having an allergic reaction. The patient has no significant medical history and takes no medications. His blood pressure is 94/62 mm Hg, heart rate is 125/min, and respiratory rate is 22/min. On physical examination, his lips are edematous and he has severe audible stridor. Of the following, which type of hypersensitivity reaction is this patient experiencing?", "answer": "Type I hypersensitivity reaction", "options": {"A": "Type I hypersensitivity reaction", "B": "Type II hypersensitivity reaction", "C": "Type III hypersensitivity reaction", "D": "Type IV hypersensitivity reaction", "E": "Combined type I and type III hypersensitivity reactions"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "You conduct a medical research study to determine the screening efficacy of a novel serum marker for colon cancer. The study is divided into 2 subsets. In the first, there are 500 patients with colon cancer, of which 450 are found positive for the novel serum marker. In the second arm, there are 500 patients who do not have colon cancer, and only 10 are found positive for the novel serum marker. What is the overall sensitivity of this novel test?", "answer": "450 / (450 + 50)", "options": {"A": "450 / (450 + 50)", "B": "490 / (10 + 490)", "C": "490 / (50 + 490)", "D": "450 / (450 + 10)", "E": "490 / (450 + 490)"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 43-year-old man comes to the physician because of weight loss and swelling on the left side of his neck. Physical examination shows a firm, enlarged left upper cervical lymph node that is immobile. Immunohistochemical testing performed on a biopsy specimen from the lymph node stains positive for cytokeratin. Which of the following is the most likely site of the primary neoplasm in this patient?", "answer": "Skin", "options": {"A": "Skin", "B": "Brain", "C": "Nerve sheath", "D": "Bone", "E": "Muscle"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old woman presents to the clinic with the complaint of excessive fatigue for the past few weeks. After returning home from the office, she feels too tired to climb up the stairs, comb her hair, or chew her food. She has occasionally experienced double vision. She denies any history of fever, cough, weight loss, night sweats, or snoring. Past history is unremarkable. Physical examination reveals: blood pressure 124/86 mm Hg, heart rate 85/min, respiratory rate 14/min, temperature 37.0°C (98.6°F), and body mass index (BMI) 22.6 kg/m2. On examination, the right upper eyelid is slightly drooping when compared to the left side. Her eye movements are normal. Flexion of the neck is mildly weak. Muscle strength is 5/5 in all 4 limbs. When she is asked to alternately flex and extend her shoulder continuously for 5 minutes, the power in the proximal upper limb muscles becomes 4/5. The muscle tone and deep tendon reflexes are normal. What is the most appropriate test to diagnose this condition?", "answer": "Single-fiber electromyography", "options": {"A": "CT scan chest", "B": "Plasmapheresis", "C": "Presynaptic calcium channel antibodies", "D": "Single-fiber electromyography", "E": "Tensilon test"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-month-old toddler presents with his mother to the pediatrician for a scheduled follow-up. She is concerned that his appetite has been poor since the death of his father, approximately one year ago. She denies any history of vomiting, refusal of food, diarrhea, constipation, recurrent cough and colds, recurrent wheezing, fast breathing, recurrent fever, or recurrent infections. The boy was born at full term by vaginal delivery with an uneventful neonatal period and infancy. His vaccines are up to date. On physical examination, his vital signs are stable. His complete physical examination does not suggest a specific medical disorder or congenital abnormality. His detailed diagnostic evaluation, including complete blood counts, serum protein, liver function tests, and urinalysis are normal. The pediatrician reviews the patient’s growth chart.\nAt the age of 18 months he was at the 90th percentile for weight and 75th for height. After plotting his current growth parameters on the growth charts, the pediatrician suspects failure to thrive with psychosocial etiology. Based on which of the following findings on the growth charts did the pediatrician suspect the condition?", "answer": "Present gender-specific weight for age between 75 and 50 percentile markers", "options": {"A": "Present gender-specific weight for age between 90 and 75 percentile markers", "B": "Present gender-specific weight for age between 75 and 50 percentile markers", "C": "Present gender-specific height for age between 90 and 75 percentile markers", "D": "Present gender-specific height for age between 75 and 50 percentile markers", "E": "Present gender-specific weight for height between 90 and 95 percentile markers"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old woman presents to her primary care physician complaining of intense thirst and frequent urination for the past 2 weeks. She says that she constantly feels the urge to drink water and is also going to the bathroom to urinate frequently throughout the day and multiple times at night. She was most recently hospitalized 1 month prior to presentation following a motor vehicle accident in which she suffered severe impact to her head. The physician obtains laboratory tests, with the results shown below:\n\nSerum:\nNa+: 149 mEq/L\nCl-: 103 mEq/L\nK+: 3.5 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 105 mg/dL\nUrine Osm: 250 mOsm/kg\n\nThe patient’s condition is most likely caused by inadequate hormone secretion from which of the following locations?", "answer": "Posterior pituitary", "options": {"A": "Adrenal cortex", "B": "Anterior pituitary", "C": "Posterior pituitary", "D": "Preoptic nucleus of the hypothalamus", "E": "Suprachiasmatic nucleus of the hypothalamus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old man presents with one week of redness and discharge in his eyes, pain and swelling in his left second and third toes, and rash on the soles of his feet. He is sexually active with multiple partners and uses condoms occasionally. He denies any recent travel or illness and does not take any medications. Review of systems is otherwise unremarkable. On physical exam, he has bilateral conjunctivitis, dactylitis of the left second and third toes, and crusty yellow-brown vesicles on his plantar feet. Complete blood count and chemistries are within normal limits. Erythrocyte sedimentation rate (ESR) is 40 mm/h. Toe radiographs demonstrate soft tissue swelling but no fractures. Which diagnostic test should be performed next?", "answer": "Nucleic acid amplification testing for Chlamydia trachomatis", "options": {"A": "Rheumatoid factor", "B": "Anti-cyclic citrullinated peptide antibody assay", "C": "Antinuclear antibody assay", "D": "HLA-B27", "E": "Nucleic acid amplification testing for Chlamydia trachomatis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 18-year old college freshman presents to his university clinic because he has not been feeling well for the past two weeks. He has had a persistent headache, occasional cough, and chills without rigors. The patient’s vital signs are normal and physical exam is unremarkable. His radiograph shows patchy interstitial lung infiltrates and he is diagnosed with atypical pneumonia. The patient is prescribed azithromycin and takes his medication as instructed. Despite adherence to his drug regimen, he returns to the clinic one week later because his symptoms have not improved. The organism responsible for this infection is likely resistant to azithromycin through which mechanism?", "answer": "Methylation of ribosomal binding site", "options": {"A": "Presence of a beta-lactamase", "B": "Insertion of drug efflux pumps", "C": "Decreased binding to RNA polymerase", "D": "Mutation in topoisomerase II", "E": "Methylation of ribosomal binding site"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A group of researchers is studying various inhaled substances to determine their anesthetic properties. In particular, they are trying to identify an anesthetic with fast onset and quick recovery for use in emergencies. They determine the following data:\nInhalational anesthetic  Blood-gas partition coefficient\nA 0.15\nB 0.92\nC 5.42\nWhich of the following statements is accurate with regard to these inhaled anesthetic substances?", "answer": "Agent A has the fastest onset of action", "options": {"A": "Agent A is the most potent", "B": "Agent A has the fastest onset of action", "C": "Agent B is the most potent", "D": "Agent B has the fastest onset of action", "E": "Agent C has the fastest onset of action"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 14-year-old boy presents to the office for a checkup. He is well-nourished and meets all developmental milestones. He denies any complaints, and you offer him counseling on adolescent issues. On examination, he appears to be a normal, healthy teenager. The only significant finding is the bilateral swelling of the tibial tuberosities. When asked about them, the patient denies trauma and states they are sore, especially when he runs or squats. Which of the following is the underlying cause of this finding?", "answer": "Osgood-Schlatter disease", "options": {"A": "Osteopetrosis", "B": "Osteitis fibrosa cystica", "C": "Paget disease", "D": "Ewing sarcoma", "E": "Osgood-Schlatter disease"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old female presents to the emergency department with monocular blindness. She states that early this morning she lost her vision seemingly \"out of nowhere.\" She denies trauma or any precipitating factors. She does state though that over the past year she has had occasional episodes of weakness and even an episode of urinary incontinence, which always resolve on their own. On exam, pain is elicited with eye movement and nystagmus is appreciated. The emergency physician performs a lumbar puncture. What is most likely to be observed in the CSF of this patient?", "answer": "Oligoclonal bands", "options": {"A": "Increased opening pressure", "B": "Oligoclonal bands", "C": "Albuminocytologic dissociation", "D": "Increased lymphocyte count", "E": "Normal findings"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "ََA 22-month-old girl is brought to the emergency department with a 24-hour history of fever, irritability, and poor feeding. The patient never experienced such an episode in the past. She met the normal developmental milestones, and her vaccination history is up-to-date. She takes no medications, currently. Her temperature is 38.9°C (102.0°F). An abdominal examination reveals general tenderness without organomegaly. The remainder of the physical examination shows no abnormalities. Laboratory studies show the following results:\nUrine\nBlood 1+\nWBC 10–15/hpf\nBacteria Many\nNitrite Positive\nUrine culture from a midstream collection reveals 100,000 CFU/mL of Escherichia coli. Which of the following interventions is the most appropriate next step in evaluation?", "answer": "Renal and bladder ultrasonography", "options": {"A": "Dimercaptosuccinic acid renal scan", "B": "Intravenous pyelography", "C": "Renal and bladder ultrasonography", "D": "Voiding cystourethrography", "E": "No further testing"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old woman presents to her primary care physician for a routine check-up. She complains that she is not feeling her normal self, but has no specific complaints. After a routine examination, the physician orders a full thyroid workup, including TSH, T3, and free T4. He also refers her directly to an oncologist for an initial consultation. Which type of lymphadenopathy was most likely present during the physical examination that made the primary care physician react this way?", "answer": "Localized painless lymphadenopathy", "options": {"A": "Generalized painful lymphadenopathy", "B": "Generalized painless lymphadenopathy", "C": "Reactive lymphadenitis", "D": "Localized painful lymphadenopathy", "E": "Localized painless lymphadenopathy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old man presents to his primary care physician to discuss laboratory results that were obtained during his annual checkup. He has no symptoms or concerns and denies changes in eating or urination patterns. Specifically, the physician ordered a panel of metabolic laboratory tests to look for signs of diabetes, hyperlipidemia, or other chronic disorders. A spot glucose check from a random blood sample showed a glucose level of 211 mg/dL. A hemoglobin A1c level was obtained at the same time that showed a level of 6.3%. A fasting blood glucose was obtained that showed a blood glucose level of 125 mg/dL. Finally, a 2-hour glucose level was obtained after an oral glucose tolerance test that showed a glucose level of 201 mg/dL. Which of the following statements is most accurate for this patient?", "answer": "This patient has type 2 diabetes as diagnosed by his oral tolerance blood glucose", "options": {"A": "This patient does not have type 2 diabetes", "B": "This patient has type 2 diabetes as diagnosed by his fasting blood glucose", "C": "This patient has type 2 diabetes as diagnosed by his hemoglobin A1c", "D": "This patient has type 2 diabetes as diagnosed by his oral tolerance blood glucose", "E": "This patient has type 2 diabetes as diagnosed by his random blood glucose"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old man is brought to the emergency department from a kitchen fire. The patient was cooking when boiling oil splashed on his exposed skin. His temperature is 99.7°F (37.6°C), blood pressure is 127/82 mmHg, pulse is 120/min, respirations are 12/min, and oxygen saturation is 98% on room air. He has dry, nontender, and circumferential burns over his arms bilaterally, burns over the anterior portion of his chest and abdomen, and tender spot burns with blisters on his shins. A 1L bolus of normal saline is administered and the patient is given morphine and his pulse is subsequently 80/min. A Foley catheter is placed which drains 10 mL of urine. What is the best next step in management?", "answer": "Additional fluids and escharotomy", "options": {"A": "Additional fluids and admission to the ICU", "B": "Additional fluids and escharotomy", "C": "Continuous observation", "D": "Escharotomy", "E": "Moist dressings and discharge"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 8-year-old girl is brought to the physician by her parents for the evaluation of an episode of unconsciousness while at the playground that morning. She was unconscious for about 15 seconds and did not shake, bite her tongue, or lose bowel or bladder control. Her grandfather died suddenly at the age of 29 of an unknown heart condition; her parents are both healthy. An ECG shows sinus rhythm and a QT interval corrected for heart rate (QTc) of 470 milliseconds. Laboratory studies are within normal limits. Which of the following is the most likely additional finding in this patient?", "answer": "Sensorineural hearing loss", "options": {"A": "Oblique palpebral fissures", "B": "Sensorineural hearing loss", "C": "Skin folds between the mastoid process and acromion", "D": "Brachial-femoral pulse delay", "E": "Subvalvular ventricular outflow obstruction murmur"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old woman presents to the emergency department with abdominal pain. Her pain started last night during dinner and has persisted. This morning, the patient felt very ill and her husband called emergency medical services. The patient has a past medical history of obesity, diabetes, and depression. Her temperature is 104°F (40°C), blood pressure is 90/65 mmHg, pulse is 160/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam is notable for a very ill appearing woman. Her skin is mildly yellow, and she is in an antalgic position on the stretcher. Laboratory values are ordered as seen below.\n\nHemoglobin: 13 g/dL\nHematocrit: 38%\nLeukocyte count: 14,500 cells/mm^3 with normal differential\nPlatelet count: 257,000/mm^3\n\nAlkaline phosphatase: 227 U/L\nBilirubin, total: 11.3 mg/dL\nBilirubin, direct: 9.8 mg/dL\nAST: 42 U/L\nALT: 31 U/L\n\nThe patient is started on antibiotics and IV fluids. Which of the following is the best next step in management?", "answer": "Endoscopic retrograde cholangiopancreatography", "options": {"A": "Emergency cholecystectomy", "B": "Endoscopic retrograde cholangiopancreatography", "C": "FAST exam", "D": "Nasogastric tube and NPO", "E": "Supportive therapy followed by elective cholecystectomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old female is undergoing renal transplantation for management of chronic renal failure secondary to glomerulonephritis. The transplant surgeon placed the donor kidney in the recipient and anastamosed the donor renal artery to the recipient's external iliac artery as well as the donor ureter to the recipient's bladder. After removing the clamps on the external iliac artery, the recipient's blood is allowed to perfuse the transplanted kidney. Within 3 minutes, the surgeon notes that the kidney does not appear to be sufficiently perfused. Upon further investigation, an inflammatory reaction is noted that led to clotting off of the donor renal artery, preventing blood flow to the transplanted organ. Which of the following best describes the pathophysiology of this complication?", "answer": "Type II hypersensitivity reaction", "options": {"A": "Type I hypersensitivity reaction", "B": "Type II hypersensitivity reaction", "C": "Type III hypersensitivity reaction", "D": "Type IV hypersensitivity reaction", "E": "Graft-versus-host disease"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old man is brought to the emergency department 30 minutes after the onset of uncontrollable jerking movements of his arms and legs followed by loss of consciousness. His wife says that he seemed confused this morning and had a headache. Immediately before the shaking episode, he said that he smelled rotten eggs. He is unresponsive. Cerebrospinal fluid (CSF) analysis shows a leukocyte count of 700/μL (70% lymphocytes), a glucose concentration of 60 mg/dL, and a protein concentration of 80 mg/dL. Despite appropriate lifesaving measures, the man dies. Which of the following is most likely to be found on postmortem examination of this patient?", "answer": "Necrosis of the temporal lobes", "options": {"A": "Hemorrhage into the adrenal glands", "B": "Necrosis of the temporal lobes", "C": "Atrophy of the mammillary bodies", "D": "Spore-forming, obligate anaerobic rods", "E": "Cytoplasmic inclusions in cerebellar Purkinje cells"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old man presents to the emergency department complaining of shortness of breath and fatigue for 1 day. He reports feeling increasingly tired. The medical records show a long history of intravenous drug abuse, and a past hospitalization for infective endocarditis 2 years ago. The echocardiography performed at that time showed vegetations on the tricuspid valve. The patient has not regularly attended his follow-up appointments. The visual inspection of the neck shows distension of the neck veins. What finding would you expect to see on this patient’s jugular venous pulse tracing?", "answer": "Obliterated x descent", "options": {"A": "Absent a waves", "B": "Prominent y descent", "C": "Obliterated x descent", "D": "Decreased c waves", "E": "Large a waves"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old man is brought to the emergency department by his wife because of a 2-week history of progressive disorientation and a 1-day history of left-sided weakness and difficulty speaking. The wife reports that the patient had a minor fall 4 months ago, during which he may have hit his head. He has hypertension and hyperlipidemia. He drinks 3–4 bottles of beer daily. He is only oriented to person. Neurological examination shows moderate spastic weakness, decreased sensation, and increased deep tendon reflexes in the left upper and lower extremities. A CT scan of the head is shown. Which of the following is the most likely cause of this patient's condition?", "answer": "Tearing of bridging veins", "options": {"A": "Damage to lenticulostriate arteries", "B": "Injury to middle meningeal artery", "C": "Embolus to middle cerebral artery", "D": "Tearing of bridging veins", "E": "Bleeding from intraventricular vascular malformation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old boy with Down syndrome presents with his mother. The patient’s mother says that he isn’t playing or eating as much as he used to and seems lethargic. Expected developmental delays are present and stable. Physical examination reveals dry mucous membranes and abdominal distention with no tenderness to palpation. An abdominal radiograph is shown in the image below. Which of the following is the most likely diagnosis in this patient?", "answer": "Hirschsprung's disease", "options": {"A": "Pyloric stenosis", "B": "Ulcerative colitis", "C": "Anal atresia", "D": "Incarcerated hernia", "E": "Hirschsprung's disease"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old man with an unknown past medical history is brought to the emergency department acutely intoxicated. The patient was found passed out in a park covered in vomit and urine. His temperature is 99.0°F (37.2°C), blood pressure is 107/68 mm Hg, pulse is 120/min, respiratory rate is 13/min, and oxygen saturation is 95% on room air. Physical exam is notable for wheezing in all lung fields without any crackles. The patient is started on 2L/min nasal cannula oxygen and IV fluids. His laboratory values are notable for an AST of 200 U/L and an ALT of 100 U/L. An initial chest radiograph is unremarkable. Which of the following is the most likely explanation for this patient's pulmonary symptoms?", "answer": "Environmental antigen", "options": {"A": "Aspiration event", "B": "Bacterial infection", "C": "Clot in pulmonary vasculature", "D": "Elastic tissue destruction", "E": "Environmental antigen"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old man presents to the emergency department for bloody stools. The patient states that he has had bloody diarrhea for the past 3 days without improvement. He recently returned from a camping trip where he drank stream water and admits to eating undercooked meats which included beef, chicken, pork, and salmon. The patient's father died at age 40 due to colon cancer, and his mother died of breast cancer at the age of 52. The patient lives alone and drinks socially. The patient has unprotected sex with multiple male partners. His temperature is 98.3°F (36.8°C), blood pressure is 107/58 mmHg, pulse is 127/min, respirations are 12/min, and oxygen saturation is 99% on room air. Laboratory values are ordered as seen below.\n\nHemoglobin: 9.2 g/dL\nHematocrit: 29%\nLeukocyte count: 9,500/mm^3 with normal differential\nPlatelet count: 87,000/mm^3\nLactate dehydrogenase: 327 IU/L\nHaptoglobin: 5 mg/dL\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 5.9 mEq/L\nHCO3-: 19 mEq/L\nBUN: 39 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the most likely cause of this patient's presentation?", "answer": "Escherichia coli", "options": {"A": "Campylobacter jejuni", "B": "Colon cancer", "C": "Entamoeba histolytica", "D": "Escherichia coli", "E": "Giardia lamblia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old woman is brought to the emergency department because of an episode of lightheadedness and left arm weakness for the last hour. Her symptoms were preceded by tremors, palpitations, and diaphoresis. During the past 3 months, she has had increased appetite and has gained 6.8 kg (15 lbs). She has hypertension, hyperlipidemia, anxiety disorder, and gastroesophageal reflux. She works as a nurse in an ICU and has been under more stress than usual. She does not smoke. She drinks 5 glasses of wine every week. Current medications include enalapril, atorvastatin, fluoxetine, and omeprazole. She is 168 cm (5 ft 6 in) tall and weighs 100 kg (220 lb); BMI is 36 kg/m2. Her temperature is 37°C (98.8°F), pulse is 78/min, and blood pressure is 130/80 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. Fasting serum studies show:\nNa+ 140 mEq/L\nK+ 3.5 mEq/L\nHCO3- 22 mEq/L\nCreatinine 0.8 mg/dL\nGlucose 37 mg/dL\nInsulin 280 μU/mL (N=11–240)\nThyroid-stimulating hormone 2.8 μU/mL\nC-peptide 4.9 ng/mL (N=0.8–3.1)\nUrine screen for sulfonylurea is negative. Which of the following is the most likely diagnosis?\"", "answer": "Insulinoma", "options": {"A": "Polycystic ovarian syndrome", "B": "Insulinoma", "C": "Exogenous hypoglycemia", "D": "Binge eating disorder", "E": "Cushing's syndrome\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 56-year-old man presents to his primary care doctor to discuss his plans for diet and exercise. He currently has hypertension treated with thiazide diuretics but is otherwise healthy. On exam, his temperature is 98.8°F (37.1°C), blood pressure is 122/84 mmHg, pulse is 70/min, and respirations are 12/min. His weight is 95.2 kilograms and his BMI is 31.0 kg/m^2. The patient is recommended to follow a 2000 kilocalorie diet with a 30:55 caloric ratio of fat to carbohydrates. Based on this patient’s body mass index and weight, he is recommended to consume 75 grams of protein per day. Which of the following represents the approximate number of grams of carbohydrates the patient should consume per day?", "answer": "275", "options": {"A": "67", "B": "122", "C": "232", "D": "275", "E": "324"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old man is rushed to the emergency department 30 minutes after diving head-first into a shallow pool of water from a cliff. He was placed on a spinal board and a rigid cervical collar was applied by the emergency medical technicians. On arrival, he is unconscious and withdraws all extremities to pain. His temperature is 36.7°C (98.1°F), pulse is 70/min, respirations are 8/min, and blood pressure is 102/70 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. The pupils are equal and react sluggishly to light. There is a 3-cm (1.2-in) laceration over the forehead. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft and nontender. There is a step-off palpated over the cervical spine. Which of the following is the most appropriate next step in management?", "answer": "Rapid sequence intubation", "options": {"A": "CT scan of the spine", "B": "X-ray of the cervical spine", "C": "Rapid sequence intubation", "D": "Rectal tone assessment", "E": "MRI of the spine\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old male with a past medical history significant for aortic stenosis and hypertension presents to the emergency department complaining of weakness for the past 3 weeks. He states that, apart from feeling weaker, he also has noted lightheadedness, pallor, and blood-streaked stools. The patient's vital signs are stable, and he is in no acute distress. Laboratory workup reveals that the patient is anemic. Fecal occult blood test is positive for bleeding. EGD was performed and did not reveal upper GI bleeding. Suspecting a lower GI bleed, a colonoscopy is performed after prepping the patient, and it is unremarkable. What would be an appropriate next step for localizing a lower GI bleed in this patient?", "answer": "Technetium-99 labelled erythrocyte scintigraphy", "options": {"A": "Nasogastric tube lavage", "B": "Technetium-99 labelled erythrocyte scintigraphy", "C": "Ultrasound of the abdomen", "D": "CT of the abdomen", "E": "Flexible sigmoidoscopy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 46-day-old baby is admitted to the pediatric ward with an elevated temperature, erosive periumbilical lesion, clear discharge from the umbilicus, and failure to thrive. She is the first child of a consanguineous couple born vaginally at 38 weeks gestation in an uncomplicated pregnancy. She was discharged home from the nursery within the first week of life without signs of infection or jaundice. The umbilical cord separated at 1 month of age with an increase in temperature and periumbilical inflammation that her mother treated with an herbal decoction. The vital signs are blood pressure 70/45 mm Hg, heart rate 129/min, respiratory rate 26/min, and temperature, 38.9°C (102.0°F). The baby's weight is between the 10th and 5th percentiles and her length is between the 50th and 75th percentiles for her age. The physical examination shows an erosive lesion with perifocal erythema in the periumbilical region with drainage but no pus. The rest of the examination is within normal limits for the patient’s age. The complete blood count shows the following results:\nErythrocytes 3.4 x 106/mm3\nHb 11 g/dL\nTotal leukocyte count\nNeutrophils\nLymphocyte\nEosinophils\nMonocytes\nBasophils 49.200/mm3\n61%\n33%\n2%\n2%\n2%\nPlatelet count 229,000/mm3\nThe umbilical discharge culture shows the growth of Staphylococcus aureus. Flow cytometry is performed for suspected primary immunodeficiency. The patient is shown to be CD18-deficient. Which of the following statements best describes the patient’s condition?", "answer": "The patient’s leukocytes fail to adhere to the endothelium during their migration to the site of infection.", "options": {"A": "The patient’s neutrophils fail to produce reactive oxygen species to destroy engulfed bacteria.", "B": "The patient’s leukocytes cannot interact with selectins expressed on the surface of endothelial cells.", "C": "The patient’s leukocytes fail to adhere to the endothelium during their migration to the site of infection.", "D": "There is excessive secretion of IL-2 in this patient.", "E": "The patient has impaired formation of membrane attack complex."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 8-year-old boy is brought to the physician because of a 7-day history of a progressively worsening cough. The cough occurs in spells and consists of around 5–10 coughs in succession. After each spell he takes a deep, noisy breath. He has vomited occasionally following a bout of coughing. He had a runny nose for a week before the cough started. His immunization records are unavailable. He lives in an apartment with his father, mother, and his 2-week-old sister. The mother was given a Tdap vaccination 11 years ago. The father's vaccination records are unavailable. His temperature is 37.8°C (100.0°F). Examination shows no abnormalities. His leukocyte count is 42,000/mm3. Throat swab culture and PCR results are pending. Which of the following are the most appropriate recommendations for this family?", "answer": "Administer oral azithromycin to all family members and Tdap vaccination to the father and mother", "options": {"A": "Administer oral azithromycin to the baby and father and Tdap vaccination to the father", "B": "Administer oral azithromycin to all family members and Tdap vaccination to the father and mother", "C": "Administer oral erythromycin to all family members and Tdap vaccination to the father", "D": "Administer oral trimethoprim-sulfamethaxazole to the father and baby and Tdap vaccination to the father", "E": "Administer oral azithromycin to all family members and Tdap vaccination to the father"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying the recycling of heme proteins in various cell types. Heat denaturation and high-performance liquid chromatography are used to carry out and observe the selective destruction of hemoglobin molecules in red blood cells. It is found that these cells are unable to regenerate new heme molecules. A lack of which of the following structures is the most likely explanation for this observation?", "answer": "Mitochondria", "options": {"A": "Golgi apparatus", "B": "Mitochondria", "C": "Smooth endoplasmic reticulum", "D": "Nucleus", "E": "Peroxisomes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-year-old boy is brought to the emergency department by his parents for worsening symptoms. The patient recently saw his pediatrician for an acute episode of sinusitis. At the time, the pediatrician prescribed decongestants and sent the patient home. Since then, the patient has developed a nasal discharge with worsening pain. The patient has a past medical history of asthma which is well controlled with albuterol. His temperature is 99.5°F (37.5°C), blood pressure is 90/48 mmHg, pulse is 124/min, respirations are 17/min, and oxygen saturation is 98% on room air. On physical exam, you note a healthy young boy. Cardiopulmonary exam is within normal limits. Inspection of the patient's nose reveals a unilateral purulent discharge mixed with blood. The rest of the patient's exam is within normal limits. Which of the following is the most likely diagnosis?", "answer": "Foreign body obstruction", "options": {"A": "Bleeding and infected vessel of Kiesselbach plexus", "B": "Foreign body obstruction", "C": "Nasopharyngeal carcinoma", "D": "Septal perforation", "E": "Sinusitis with bacterial superinfection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old woman delivers a girl by normal vaginal delivery, Apgar scores are 8 and 9 at 1 and 5 minutes respectively. The newborn’s vitals are normal. On examination, the attending pediatrician finds a circular skin defect that measures 0.5 cm in diameter. The defect is hairless and extends into the dermis. The delivery was atraumatic and there were no surgical instruments in the area. The pediatric team believes this is a congenital defect. The remaining examination is normal. The mother gives past history of having constant diarrhea for 3 months about 2 years ago, weight loss of 5 kg (11 lb) in 3 months, palpitations, and sensitivity to heat. She visited a community hospital and was prescribed a medication for this problem. She did not visit the hospital for any of her routine check-ups and continued taking her medications. Which drug can predispose the newborn to this condition?", "answer": "Methimazole", "options": {"A": "Propylthiouracil", "B": "Methimazole", "C": "Propranolol", "D": "Levothyroxine", "E": "Octreotide"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 63-year-old man comes to the physician because of a 2-day history of a painful rash on his right flank. Two years ago, he underwent cadaveric renal transplantation. Current medications include tacrolimus, mycophenolate mofetil, and prednisone. Examination shows an erythematous rash with grouped vesicles in a band-like distribution over the patient's right flank. This patient is at greatest risk for which of the following complications?", "answer": "Sensory neuropathy", "options": {"A": "Sensory neuropathy", "B": "Ascending paralysis", "C": "Urinary retention", "D": "Loss of vision", "E": "Temporal lobe inflammation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 16-year-old girl is brought to the emergency room with hyperextension of the cervical spine caused by a trampoline injury. After ruling out the possibility of hemorrhagic shock, she is diagnosed with quadriplegia with neurogenic shock. The physical examination is most likely to reveal which of the following constellation of findings?", "answer": "Pulse: 56/min; blood pressure: 88/40 mm Hg; respirations: 22/min; loss of rectal tone on DRE; reduced muscle power and absence of sensations in the limbs", "options": {"A": "Pulse: 110/min; blood pressure: 88/50 mm Hg; respirations: 26/min; normal rectal tone on digital rectal examination (DRE); normal muscle power and sensations in the limbs", "B": "Pulse: 99/min; blood pressure: 188/90 mm Hg; respirations: 33/min; loss of rectal tone on DRE; reduced muscle power and absence of sensations in the limbs", "C": "Pulse: 56/min; blood pressure: 88/40 mm Hg; respirations: 22/min; loss of rectal tone on DRE; reduced muscle power and absence of sensations in the limbs", "D": "Pulse: 54/min; blood pressure: 88/44 mm Hg; respirations: 26/min; increased rectal tone on DRE; normal muscle power and sensations in the limbs", "E": "Pulse: 116/min; blood pressure: 80/40 mm Hg; respirations: 16/min; loss of rectal tone on DRE; reduced muscle power and absence of sensations in the limbs"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 64-year-old woman presents to the clinic with a history of 3 fractures in the past year with the last one being last month. Her bone-density screening from last year reported a T-score of -3.1 and she was diagnosed with osteoporosis. She was advised to quit smoking and was asked to adapt to a healthy lifestyle to which she complied. She was also given calcium and vitamin D supplements. After a detailed discussion with the patient, the physician decides to start her on weekly alendronate. Which of the following statements best describes this patient’s new therapy?", "answer": "The patient must stay upright for at least 30 minutes after taking this medication", "options": {"A": "It is typically used as a second-line therapy for her condition after raloxifene", "B": "It must be taken with the first meal of the day due to the significant risk of GI upset", "C": "The patient must stay upright for at least 30 minutes after taking this medication", "D": "It can cause hot flashes, flu-like symptoms, and peripheral edema", "E": "It should be stopped after 10 years due to the risk of esophageal cancer"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old woman comes to the physician for a routine health maintenance examination. She feels well. She had a chlamydia infection at the age of 22 years that was treated. Her only medication is an oral contraceptive. She has smoked one pack of cigarettes daily for 6 years. She has recently been sexually active with 3 male partners and uses condoms inconsistently. Her last Pap test was 4 years ago and results were normal. Physical examination shows no abnormalities. A Pap test shows atypical squamous cells of undetermined significance. Which of the following is the most appropriate next step in management?", "answer": "Perform HPV testing", "options": {"A": "Perform cervical biopsy", "B": "Perform loop electrosurgical excision procedure", "C": "Perform HPV testing", "D": "Repeat cytology in 6 months", "E": "Perform laser ablation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old pregnant woman (gravida 2, para 1) presents on her 25th week of pregnancy. Currently, she has no complaints. Her previous pregnancy was unremarkable. No abnormalities were detected on the previous ultrasound (US) examination at week 13 of pregnancy. She had normal results on the triple test. She is human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV)-negative. Her blood type is III(B) Rh+, and her partner has blood type I(0) Rh-. She and her husband are both of Sardinian descent, do not consume alcohol, and do not smoke. Her cousin had a child who died soon after the birth, but she doesn't know the reason. She does not report a history of any genetic conditions in her family, although notes that her grandfather “was always yellowish-pale, fatigued easily, and had problems with his gallbladder”. Below are her and her partner’s complete blood count and electrophoresis results.\nComplete blood count\n  Patient Her husband\nErythrocytes 3.3 million/mm3 4.2 million/mm3\nHb 11.9 g/dL 13.3 g/dL\nMCV 71 fL 77 fL\nReticulocyte count 0.005 0.008\nLeukocyte count 7,500/mm3 6,300/mm3\nPlatelet count 190,000/mm3 256,000/mm3\nElectrophoresis\nHbA1 95% 98%\nHbA2 3% 2%\nHbS 0% 0%\nHbH 2% 0%\nThe patient undergoes ultrasound examination which reveals ascites, liver enlargement, and pleural effusion in the fetus. Further evaluation with Doppler ultrasound shows elevated peak systolic velocity of the fetal middle cerebral artery. Which of the following procedures can be performed for both diagnostic and therapeutic purposes in this case?", "answer": "Cordocentesis", "options": {"A": "Fetoscopy", "B": "Amniocentesis", "C": "Chorionic villus sampling", "D": "Cordocentesis", "E": "Percutaneous fetal thoracentesis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "DNA replication is a highly complex process where replication occurs on both strands of DNA. On the leading strand of DNA, replication occurs uninteruppted, but on the lagging strand, replication is interrupted and occurs in fragments called Okazaki fragments. These fragments need to be joined, which of the following enzymes is involved in the penultimate step before ligation can occur?", "answer": "DNA polymerase I", "options": {"A": "DNA ligase", "B": "DNA gyrase", "C": "DNA helicase", "D": "DNA polymerase I", "E": "DNA polymerase III"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-day-old boy develops several episodes of complete body shaking while at the hospital. The episodes last for about 10–20 seconds. He has not had fever or trauma. He was born at 40 weeks' gestation and has been healthy. The mother did not follow-up with her gynecologist during her pregnancy on a regular basis. There is no family history of serious illness. The patient appears irritable. Vital signs are within normal limits. Physical examination shows reddening of the face. Peripheral venous studies show a hematocrit of 68%. Neuroimaging of the head shows several cerebral infarctions. Which of the following is the most likely cause of this patient's findings?", "answer": "Maternal diabetes", "options": {"A": "Maternal diabetes", "B": "Neonatal listeria infection", "C": "Neonatal JAK2 mutation", "D": "Neonatal factor V mutation", "E": "Maternal alcohol use during pregnancy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-month-old boy is brought to the physician by his mother because of poor weight gain. She also reports a dusky blue discoloration to his skin during feedings and when crying. On examination, there is a harsh, systolic murmur heard over the left upper sternal border. An x-ray of the chest is shown below. Which of the following is the most likely cause of his symptoms?", "answer": "Right ventricular outflow obstruction", "options": {"A": "Persistent connection between the aorta and pulmonary artery", "B": "Hypoplasia of the left ventricle", "C": "Narrowing of the distal aortic arch", "D": "Right ventricular outflow obstruction", "E": "Anatomic reversal of aorta and pulmonary artery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old male presents to his primary care physician with pain along the bottom of his foot. The patient is a long-time runner but states that the pain has been getting worse recently. He states that when running and at rest he has a burning and aching pain along the bottom of his foot that sometimes turns to numbness. Taking time off from training does not improve his symptoms. The patient has a past medical history of surgical repair of his Achilles tendon, ACL, and medial meniscus. He is currently not taking any medications. The patient lives with his wife and they both practice a vegan lifestyle. On physical exam the patient states that he is currently not experiencing any pain in his foot but rather is experiencing numbness/tingling along the plantar surface of his foot. Strength is 5/5 and reflexes are 2+ in the lower extremities. Which of the following is the most likely diagnosis?", "answer": "Tarsal tunnel syndrome", "options": {"A": "Vitamin B12 deficiency", "B": "Common fibular nerve compression", "C": "Herniated disc", "D": "Tarsal tunnel syndrome", "E": "Plantar fasciitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 64-year-old woman comes to the physician because of a dry cough and progressively worsening shortness of breath for the past 2 months. She has not had fever, chills, or night sweats. She has smoked one pack of cigarettes daily for the past 45 years. She appears thin. Examination of the lung shows a prolonged expiratory phase and end-expiratory wheezing. Spirometry shows decreased FEV1:FVC ratio (< 70% predicted), decreased FEV1, and a total lung capacity of 125% of predicted. The diffusion capacity of the lung (DLCO) is decreased. Which of the following is the most likely diagnosis?", "answer": "Chronic obstructive pulmonary disease", "options": {"A": "Bronchial asthma", "B": "Bronchiectasis", "C": "Hypersensitivity pneumonitis", "D": "Interstitial lung disease", "E": "Chronic obstructive pulmonary disease"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 33-year-old man presents to the clinic complaining of multiple painful joints for the past 2 weeks. The patient notes no history of trauma or any joint disorders. The patient states that he is generally healthy except for a recent emergency room visit for severe bloody diarrhea, which has resolved. On further questioning, the patient admits to some discomfort with urination but notes no recent sexual activity. On examination, the patient is not in acute distress, with no joint deformity, evidence of trauma, swelling, or erythema. He has a decreased range of motion of his right knee secondary to pain. Vital signs are as follows: heart rate 75/min, blood pressure 120/78 mm Hg, respiratory rate 16/min, and temperature 37.3°C (99.0°F). What is the next step in the treatment of this patient?", "answer": "Nonsteroidal anti-inflammatory drugs (NSAIDs) or immunosuppressants", "options": {"A": "Intravenous (IV) antibiotics", "B": "Nonsteroidal anti-inflammatory drugs (NSAIDs) or immunosuppressants", "C": "Positron emission tomography (PET) scan", "D": "Serology for rheumatoid factor", "E": "Prostate biopsy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 28-year-old woman presents to the emergency department with lateral knee pain that started this morning. The patient is a college student who is currently on the basketball team. She states her pain started after she twisted her knee. Her current medications include albuterol and ibuprofen. The patient's vitals are within normal limits and physical exam is notable for tenderness to palpation over the lateral right knee. When the patient lays on her left side and her right hip is extended and abducted it does not lower to the table in a smooth fashion and adduction causes discomfort. The rest of her exam is within normal limits. Which of the following is the most likely diagnosis?", "answer": "Iliotibial band syndrome", "options": {"A": "Iliotibial band syndrome", "B": "Lateral collateral ligament injury", "C": "Musculoskeletal strain", "D": "Patellofemoral syndrome", "E": "Pes anserine bursitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 56-year-old man comes to the physician for a follow-up examination. One month ago, he was diagnosed with a focal seizure and treatment with a drug that blocks voltage-gated sodium channels was begun. Today, he reports that he has not had any abnormal body movements, but he has noticed occasional double vision. His serum sodium is 132 mEq/L, alanine aminotransferase is 49 U/L, and aspartate aminotransferase is 46 U/L. This patient has most likely been taking which of the following drugs?", "answer": "Carbamazepine", "options": {"A": "Carbamazepine", "B": "Levetiracetam", "C": "Gabapentin", "D": "Lamotrigine", "E": "Topiramate"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 22-year-old woman comes to the physician to discuss the prescription of an oral contraceptive. She has no history of major medical illness and takes no medications. She does not smoke cigarettes. She is sexually active with her boyfriend and has been using condoms for contraception. Physical examination shows no abnormalities. She is prescribed combined levonorgestrel and ethinylestradiol tablets. Which of the following is the most important mechanism of action of this drug in the prevention of pregnancy?", "answer": "Inhibition of rise in luteinizing hormone", "options": {"A": "Thickening of cervical mucus", "B": "Inhibition of rise in luteinizing hormone", "C": "Suppression of ovarian folliculogenesis", "D": "Increase of sex-hormone binding globulin", "E": "Prevention of endometrial proliferation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 13-year-old boy is brought to the emergency department by his mother because of vomiting and severe testicular pain for 3 hours. The boy has had 4–5 episodes of vomiting during this period. He has never had a similar episode in the past and takes no medications. His father died of testicular cancer at the age of 50. His immunizations are up-to-date. He appears anxious and uncomfortable. His temperature is 37°C (98.6°F), pulse is 90/min, respirations are 14/min, and blood pressure is 100/60 mm Hg. Cardiopulmonary examination shows no abnormalities The abdomen is soft and nondistended. The left scrotum is firm, erythematous, and swollen. There is severe tenderness on palpation of the scrotum that persists on elevation of the testes. Stroking the inner side of the left thigh fails to elicit elevation of the scrotum. Which of the following is the most appropriate next step in management?", "answer": "Surgical exploration of the scrotum", "options": {"A": "Urine dipstick", "B": "Surgical exploration of the scrotum", "C": "Close observation", "D": "CT scan of the abdomen and pelvis", "E": "Ceftriaxone and doxycycline therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman comes to the physician for a screening health examination that is required for scuba diving certification. The physician asks her to perform a breathing technique: following deep inspiration, she is instructed to forcefully exhale against a closed airway and contract her abdominal muscles while different cardiovascular parameters are evaluated. Which of the following effects is most likely after 10 seconds in this position?", "answer": "Decreased left ventricular stroke volume", "options": {"A": "Increased venous return to left atrium", "B": "Decreased systemic vascular resistance", "C": "Decreased left ventricular stroke volume", "D": "Decreased intra-abdominal pressure", "E": "Decreased pulse rate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 71-year-old man comes to the physician for a health maintenance examination. Aside from occasional lower back pain in the last couple of years, he feels well. He had a right-sided myocardial infarction 4 years ago. Currently, he has no shortness of breath and has no anginal symptoms. He has a 30 pack-year history of smoking but stopped smoking 10 years ago and does not drink alcohol. His pulse is 59/min, and his blood pressure is 135/75 mm Hg. Physical examination reveals 1+ lower extremity edema. Cardiac and pulmonary auscultation show no abnormalities. There is no lymphadenopathy. His laboratory studies show a hemoglobin of 13.2 g/dL and serum protein of 10.1 g/dL. ECG shows known Q wave abnormalities unchanged since the last ECG one year ago. A serum protein electrophoresis with immunofixation is shown. Which of the following is the most appropriate next step to establish the diagnosis?", "answer": "Whole-body CT scan", "options": {"A": "Bone densitometry", "B": "Rectal biopsy", "C": "Echocardiography", "D": "Whole-body CT scan", "E": "Urine dipstick\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 75-year-old man presents to his primary care provider with malaise and low-grade fever after he underwent a cystoscopy for recurrent cystitis and pyelonephritis two weeks ago. His past medical history is significant for coronary artery disease and asthma. His current medications include aspirin, metoprolol, atorvastatin, and albuterol inhaler. Temperature is 37.2°C (99.0°F), blood pressure is 110/70 mm Hg, pulse is 92/min and respirations are 14/min. On physical examination, there are painless areas of hemorrhage on his palms and soles. Cardiac auscultation reveals a new pansystolic murmur over the apex. An echocardiogram shows echogenic endocardial vegetation on a leaflet of the mitral valve. Which of the following pathogens is most likely responsible for his condition?", "answer": "Enterococcus", "options": {"A": "Staphylococcus aureus", "B": "Staphylococcus epidermidis", "C": "Streptococcus gallolyticus", "D": "Enterococcus", "E": "Pseudomonas aeruginosa"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-month-old girl is brought to her primary care physician for a follow-up visit to receive the 4th dose of her DTaP vaccine. She is up-to-date on her vaccinations. She received her 1st dose of MMR, 1st dose of varicella, 3rd dose of HiB, 4th dose of PCV13, and 3rd dose of polio vaccine 3 months ago. Thirteen days after receiving these vaccinations, the child developed a fever up to 40.5°C (104.9°F) and had one generalized seizure that lasted for 2 minutes. She was taken to the emergency department. The girl was sent home after workup for the seizure was unremarkable and her temperature subsided with acetaminophen therapy. She has not had any other symptoms since then. She has no history of serious illness and takes no medications. Her mother is concerned about receiving further vaccinations because she is afraid of the girl having more seizures. Her vital signs are within normal limits. Examination shows no abnormalities. Which of the following is the most appropriate recommendation at this time?", "answer": "Administration of the DTaP vaccine as scheduled", "options": {"A": "Refrain from administration of the DTaP vaccine", "B": "Administration of the DTaP vaccine with prophylactic aspirin", "C": "Administration of the DTaP vaccine as scheduled", "D": "Administration of the DTaP vaccine with valproic acid", "E": "Administration of a reduced-dose DTaP vaccine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 46-year-old man comes to the physician for a follow-up examination. He has type 2 diabetes mellitus and hypertension. Current medications include metformin and lisinopril. He reports that he has adhered to his diet and medication regimen. His hemoglobin A1c is 8.6%. Insulin glargine is added to his medication regimen. Which of the following sets of changes is most likely to occur in response to this new medication?\n$$$ Glycolysis %%% Glycogenesis %%% Lipolysis %%% Gluconeogenesis $$$", "answer": "↑ ↑ ↓ ↓", "options": {"A": "↑ ↓ ↑ ↓", "B": "↑ ↑ ↓ ↓", "C": "↓ ↓ ↑ ↑", "D": "↓ ↑ ↓ ↑", "E": "↑ ↓ ↑ ↑"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 39-year-old woman with multiple sclerosis comes to the physician for a follow-up examination. Over the past 3 years, she has been hospitalized 7 times for acute exacerbations of her illness. She has not responded to therapy with several disease-modifying agents and has required at least two pulse corticosteroid therapies every year. She has seen several specialists and sought out experimental therapies. During this time period, her disease course has been rapidly progressive. She currently requires a wheelchair and is incontinent. Today, she says, “I'm not going to allow myself to hope because I'll only be disappointed, like I have been over and over again. What's the point? No one in this system knows how to help me. Sometimes I don't even take my pills any more because they don't help.” Which of the following is the most appropriate initial response to this patient?", "answer": "\"\"\"I'm very sorry to hear that you feel this way about your situation. With all that you've been through, I can see why you would be so frustrated.\"\"\"", "options": {"A": "\"\"\"I am moved by your courage in the face of this senseless tragedy. I agree with you that further therapy is futile, and I am going to recommend that we stop further treatments.\"\"\"", "B": "\"\"\"While I completely understand your hopelessness about the lack of improvement, not taking your medication as instructed is only going to make things worse.\"\"\"", "C": "\"\"\"I'm very sorry to hear that you feel this way about your situation. With all that you've been through, I can see why you would be so frustrated.\"\"\"", "D": "\"\"\"I understand how your illness would make you angry. Apparently your previous doctors did not know how to help you handle your condition well, but I believe I can help you.\"\"\"", "E": "\"\"\"I am concerned that this terrible illness may be affecting your capacity to make decisions for yourself and would like to refer you to a psychiatrist.\"\"\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man comes to the emergency room for a persistent painful erection for the last 5 hours. He has a history of sickle cell trait, osteoarthritis, insomnia, social anxiety disorder, gout, type 2 diabetes mellitus, major depressive disorder, and hypertension. He drinks 1 can of beer daily, and smokes marijuana on the weekends. He takes propranolol, citalopram, trazodone, rasburicase, metformin, glyburide, lisinopril, and occasionally ibuprofen. He is alert and oriented but in acute distress. Temperature is 36.5°C(97.7°F), pulse is 105/min, and blood pressure is 145/95 mm Hg. Examination shows a rigid erection with no evidence of trauma, penile discharge, injection, or prosthesis. Which of the following is the most likely cause of his condition?", "answer": "Trazodone", "options": {"A": "Trazodone", "B": "Marijuana use", "C": "Sickle cell trait", "D": "Citalopram", "E": "Propranolol"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old man presents with severe chronic neck pain. 6 months ago, the patient was in a motor vehicle accident where he sustained a severe whiplash injury. Initial radiographs were negative for fractures, and he was treated with cyclobenzaprine and tramadol and discharged with outpatient follow-up. He says that despite being compliant with his medication, the pain is not going away. It keeps him up at night and prevents him from focusing at work or at home. He also feels that none of the other doctors can help him. Past medical history includes hypertension, hyperlipidemia, and gout for which he takes chlorthalidone, atorvastatin, and allopurinol. He has no family and lives alone. He has never attempted to take his life but thinks that it might be better than living in pain forever. He has a gun at home and plans to commit suicide in the near future. Which of the following is the single best initial treatment option for this patient’s condition?", "answer": "Admission into the hospital", "options": {"A": "Admission into the hospital", "B": "Treat the patient with outpatient pharmacotherapy and psychotherapy only", "C": "Treat the the patient with outpatient psychotherapy only", "D": "Treat the patient with outpatient pharmacotherapy only", "E": "Work with local police to confiscate the gun and release the patient home"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 7-year-old boy is brought to the emergency department because of photophobia and pruritus on the periocular area of the right eye for the last 2 days. He also had crusts over the eyelashes of the right eye that morning. The boy has a history of asthma and atopic dermatitis. His medications include inhaled steroids and salbutamol. Vital signs are within normal limits. Physical examination shows conjunctival injection and redness in the affected eye, as well as a watery discharge from it. There are multiple vesicles with an erythematous base located on the upper and lower eyelids. Visual acuity is within normal limits. Which of the following is the most likely cause?", "answer": "Herpes simplex virus", "options": {"A": "Molluscum contagiosum virus", "B": "Chlamydia trachomatis", "C": "Adenovirus", "D": "Staphylococcus aureus", "E": "Herpes simplex virus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 70-year-old man presents for a routine checkup. He says that he recently completely lost hearing in both ears and has been having occasional flare-ups of osteoarthritis in his hands and hips. Past medical history is significant for hypertension diagnosed 25 years ago that is well controlled. Family history is significant for his brother, who recently died from prostate cancer. The patient's blood pressure is 126/84 mm Hg. Laboratory findings are significant for an alkaline phosphatase level that is more than 3 times the upper limit. Right upper quadrant ultrasound and non-contrast computed tomography of the abdomen and pelvis reveal no significant abnormalities. Which of the following is the most likely complication of this patient’s condition?", "answer": "Osteosarcoma", "options": {"A": "Pulmonary metastasis", "B": "Cushing syndrome", "C": "Osteoid osteoma", "D": "Hypoparathyroidism", "E": "Osteosarcoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A six year-old female presents for evaluation of dry skin, fatigue, sensitivity to cold and constipation. The patient’s mother recalls that the patient had surgery to remove a “benign mass” at the base of her tongue 3 months ago because of trouble swallowing. What was the likely cause of the surgically removed mass?", "answer": "Failed caudal migration of the thyroid gland", "options": {"A": "Maternal Diabetes Mellitus", "B": "Radiation exposure", "C": "Iodine deficiency", "D": "Failed caudal migration of the thyroid gland", "E": "Failed fusion of the palatine shelves with the nasal septum"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "During normal respiration in the lungs, oxygen is absorbed into the bloodstream and carbon dioxide is released. The oxygen is used in cells as the final electron acceptor during oxidative phosphorylation, and carbon dioxide is generated during each turn of the tricarboxylic citric acid cycle (TCA). Which of the following steps in the TCA cycle generates a molecule of carbon dioxide?", "answer": "Isocitrate to alpha ketoglutarate", "options": {"A": "Citrate to isocitrate", "B": "Isocitrate to alpha ketoglutarate", "C": "Succinyl-CoA to succinate", "D": "Fumarate to Malate", "E": "Malate to oxaloacetate"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old man presents to the emergency room after an industrial accident at a plastic manufacturer with altered consciousness, headache, shortness of breath, and abdominal pain. The vital signs include: blood pressure 145/80 mm Hg, heart rate 111/min, respiratory rate 27/min, and temperature 37.0℃ (98.6℉). The blood oxygen saturation on room air is 97%. On physical examination, the patient has a GCS score of 13. The skin is cherry-red and covered with perspiration. Breath and heart sounds are decreased. There is widespread tenderness on abdominal palpation. Blood testing shows the following findings:\npH 7.29\nPo2 66 mm Hg\nPco2 30 mm Hg\nNa+ 144 mEq/L\nK+ 5.1 mEq/L\nCl- 107 mEq/L\nHCO3- 11 mEq/L\nBase Excess -5 mEq/L\nLactate  22 mmol/L (198.2 mg/dL)\nInhibition of which enzyme caused this patient’s condition?", "answer": "Cytochrome C oxidase", "options": {"A": "Cytochrome C oxidase", "B": "Lactate dehydrogenase", "C": "Glucokinase", "D": "Succinyl coenzyme A synthetase", "E": "Fumarase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 57-year-old woman comes to the physician for a routine health maintenance examination. She has well-controlled type 2 diabetes mellitus, for which she takes metformin. She is 163 cm (5 ft 4 in) tall and weighs 84 kg (185 lb); BMI is 31.6 kg/m2. Her blood pressure is 140/92 mm Hg. Physical examination shows central obesity, with a waist circumference of 90 cm. Laboratory studies show:\nFasting glucose 94 mg/dl\nTotal cholesterol 200 mg/dL\nHigh-density lipoprotein cholesterol 36 mg/dL\nTriglycerides 170 mg/dL\nWithout treatment, this patient is at greatest risk for which of the following conditions?\"", "answer": "Liver cirrhosis", "options": {"A": "Central sleep apnea", "B": "Osteoporosis", "C": "Liver cirrhosis", "D": "Subarachnoid hemorrhage", "E": "Rheumatoid arthritis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old woman presented to a clinic because of dementia, hemiparesis, ataxia, aphasia, and dysarthria that developed over the last 5 days. She had a 15-year history of intravenous drug abuse and was treated for fever, cough, and shortness of breath before the onset of neurological symptoms. Her MRI shows multiple white matter lesions, as seen in the picture. Over the course of 2 weeks, the patient's condition worsens. Despite aggressive treatment, she lapses into a coma and dies. At autopsy, histologic examination of her brain tissue reveals gigantic, deformed astrocytes and oligodendrocytes with abnormal nuclei. Which of the following is the most likely cause of this woman's neurological symptoms?", "answer": "A double-stranded circular DNA virus", "options": {"A": "A double-stranded circular DNA virus", "B": "A proteinaceous infectious particle", "C": "A single-stranded linear RNA virus", "D": "An autosomal recessive lysosomal storage disease", "E": "Autoimmune attack of myelin sheaths"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man presents to the emergency department with shortness of breath and fatigue. His symptoms began insidiously and progressively worsened over the course of a month. He becomes short of breath when climbing the stairs or performing low-intensity exercises. He also needs to rest on multiple pillows in order to comfortably sleep. A few weeks ago he developed fever, malaise, and chest pain. Medical history is significant for hypertension, hypercholesterolemia, type II diabetes, and bariatric surgery performed 10 years ago. He is taking lisinopril, atorvastatin, and metformin. He drinks alcohol occasionally and does not smoke. He tried cocaine 3 days ago for the first time and has not used the illicit drug since. Physical exam is significant for bibasilar crackles, an S3 heart sound, and a laterally displaced cardiac apex. He has normal muscle tone throughout, 2+ reflexes, and an intact sensory exam. Which of the following is most likely the cause of this patient's symptoms", "answer": "Enterovirus", "options": {"A": "Alcohol use", "B": "Bariatric surgery", "C": "Cocaine use", "D": "Enterovirus", "E": "Medication side-effect"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 71-year-old man with hypertension is taken to the emergency department after the sudden onset of stabbing abdominal pain that radiates to the back. He has smoked 1 pack of cigarettes daily for 20 years. His pulse is 120/min and thready, respirations are 18/min, and blood pressure is 82/54 mm Hg. Physical examination shows a periumbilical, pulsatile mass and abdominal bruit. There is epigastric tenderness. Which of the following is the most likely underlying mechanism of this patient's current condition?", "answer": "Aortic wall stress", "options": {"A": "Aortic wall stress", "B": "Mesenteric atherosclerosis", "C": "Gastric mucosal ulceration", "D": "Abdominal wall defect", "E": "Portal vein stasis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 75-year-old man comes to the physician because of a 3-month history of upper abdominal pain, nausea, and sensation of early satiety. He has also had a 9.4-kg (20.7-lb) weight loss over the past 4 months. He has osteoarthritis. He drinks two beers every night with dinner. His only medication is ibuprofen. Esophagogastroduodenoscopy shows an ulcerated mass in the lesser curvature of the stomach. A biopsy specimen obtained during endoscopy shows irregular-shaped tubules with intraluminal mucus and debris. Which of the following is the most likely predisposing factor for this patient's condition?", "answer": "Dietary nitrates", "options": {"A": "Inflammatory bowel disease", "B": "NSAID use", "C": "Low-fiber diet", "D": "Dietary nitrates", "E": "Blood type O"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old male presents to his primary physician with the chief complaints of fever, abdominal pain, weight loss, muscle weakness, and numbness in his lower extremities. UA is normal. A biopsy of the sural nerve reveals transmural inflammation and fibrinoid necrosis of small and medium arteries. Chart review reveals a remote history of cigarette smoking as a teenager and Hepatitis B seropositivity. What is the most likely diagnosis?", "answer": "Polyarteritis nodosa", "options": {"A": "Polyarteritis nodosa", "B": "Microscopic polyangiitis", "C": "Thromboangiitis obliterans", "D": "Raynaud disease", "E": "Systemic lupus erythematosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-day-old girl is brought to the general pediatrics clinic by her mother. She was the product of an uncomplicated, full-term, standard vaginal delivery after an uncomplicated pregnancy in which the mother received regular prenatal care. This morning, after changing the child's diaper, the mother noticed that the newborn had a whitish, non-purulent vaginal discharge. The mother has no other complaints, and the infant is eating and voiding appropriately. Vital signs are stable. Physical exam reveals moderate mammary enlargement and confirms the vaginal discharge. The remainder of the exam is unremarkable. What is the next step in management?", "answer": "No tests are needed", "options": {"A": "Order a karyotype", "B": "Begin a workup for 17 alpha-hydroxylase deficiency", "C": "Begin a workup for 21-hydroxylase deficiency", "D": "Begin a workup for 11 beta-hydroxylase deficiency", "E": "No tests are needed"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A pilot study is conducted to determine the therapeutic response of a new antidepressant drug in patients with persistent depressive disorder. Twelve participants are randomized into a control and a treatment group (n=6 patients in each). They are asked to subjectively rate the severity of their depression from 1 (low) to 10 (high) before and after taking a pill (control group = placebo; treatment group = antidepressant). The data from this study are shown in the following table:\nSubject Control group Treatment group\n  Depression ranking before intervention Depression ranking after intervention Depression ranking before intervention Depression ranking after intervention\n1 7 5 6 4\n2 8 6 8 4\n3 7 6 9 2\n4 5 5 7 5\n5 6 6 10 3\n6 9 7 6 4\nWhich of the following is the difference between the median of the depression scores before intervention in the treatment group and the control group?", "answer": "0.5", "options": {"A": "0.7", "B": "0.5", "C": "1", "D": "2", "E": "2.1"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-year-old boy with a history of multiple fractures is brought to his pediatrician by his mother, because she is concerned her child cannot hear her. On physical exam, kyphoscoliosis, poor dentition, bowing of long bones, and conductive hearing loss is noted. On genetic analysis, the patient has a COL1A1 gene mutation. The defect found in this patient is most likely associated with impaired formation of which of the following?", "answer": "Sclera", "options": {"A": "Blood vessels", "B": "Vitreous body of the eye", "C": "Lens", "D": "Cartilage", "E": "Sclera"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 43-year-old man presents with the complaint of pain in the small joints of his left hand. The pain is intermittent and cramping in nature in his 2nd and 3rd metacarpophalangeal (MCP) joints. It has progressively worsened over the past few weeks. He also reports that he has felt thirsty more often and has urinated more frequently over the past few weeks. He denies any pain during micturition. His stools are pale in color. He also reports that his skin appears to be darker than usual even though he has not been outdoors much over the past few weeks. Physical exam is significant for tenderness in the 2nd and 3rd MCPs of both hands as well as tenderness in the right upper quadrant of his abdomen. Lab results show:\nAspartate aminotransferase (AST) 450 U/L\nAlanine aminotransferase (ALT) 350 U/L\nSerum ferritin 460 ng/mL\nDeficiency of which of the following is the most likely cause of his symptoms?", "answer": "Hepcidin", "options": {"A": "Transferrin", "B": "Pyridoxine", "C": "Hepcidin", "D": "Ceruloplasmin", "E": "α1-antitrypsin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 26-year-old man is brought to the hospital by his wife who complains that her husband has been behaving oddly for the past few hours. The patient’s wife says that she has known him for only 4 months. The wife is unable to give any past medical history. The patient’s speech is difficult to follow, and he seems very distracted. After 15 minutes, he becomes agitated and starts to bang his head on a nearby pillar. He is admitted to the psychiatric ward and is given an emergency medication, after which he calms down. In the next 2 days, he continues to become agitated at times and required 2 more doses of the same drug. On the 4th day of admission, he appears very weak, confused, and does not respond to questions appropriately. His vital signs include: temperature 40.0°C (104.0°F), blood pressure 160/95 mm Hg, and pulse 114/min. On physical examination, he is profusely diaphoretic. He is unable to stand upright or even get up from his bed. Which of the following is the mechanism of action of the drug which most likely caused this patient’s current condition?", "answer": "Dopamine receptor blocking", "options": {"A": "Dopamine receptor blocking", "B": "Serotonin reuptake inhibition", "C": "Agonistic effect on dopamine receptors", "D": "Histamine H2 receptor blocking", "E": "Skeletal muscle relaxation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 64-year-old man who has not seen a physician in over 20 years presents to your office complaining of recently worsening fatigue and weakness, a decreased appetite, distended abdomen, and easy bruising. His family history is notable for a mother with Hashimoto's thyroiditis, a sister with lupus and a brother with type II diabetes. On further questioning, the patient discloses a history of prior alcoholism as well as intravenous drug use, though he currently only smokes a pack per day of cigarettes. On physical exam, you note the following findings (see Figures A-C) as well as several ecchymoses and telangiectasias. As the patient has not seen a physician in many years, you obtain the following laboratory studies:\n\nLeukocyte count: 4,100/mm^3\nHemoglobin: 9.6 g/dL\nPlatelet count: 87,000/mm^3\nProthrombin time (PT): 21.0 seconds\nInternational Normalized Ratio (INR): 1.8\n\nSerum:\nCreatinine: 1.7 mg/dL\nTotal bilirubin: 3.2 mg/dL\nAspartate aminotransferase (AST): 225 U/L\nAlanine aminotransferase (ALT): 103 U/L\nAlkaline phosphatase: 162 U/L\nAlbumin: 2.6 g/dL\nSerum thyroxine (T4): 3.1 µg/dL\nThyroid-stimulating hormone (TSH): 3.4 µU/mL\n\nWhat is the cause of this patient’s low serum thyroxine?", "answer": "Decreased liver synthetic function", "options": {"A": "Autoimmune thyroiditis", "B": "Urinary loss of thyroxine-binding globulin due to nephrotic syndrome", "C": "Acute hepatitis causing an elevation in thyroxine-binding globulin", "D": "Transient central hypothyroidism (sick euthyroid syndrome)", "E": "Decreased liver synthetic function"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old woman, suspected of having colon cancer, is advised to undergo a contrast-CT scan of the abdomen. She has no comorbidities and no significant past medical history. There is also no history of drug allergy. However, she reports that she is allergic to certain kinds of seafood. After tests confirm normal renal function, she is taken to the CT scan room where radiocontrast dye is injected intravenously and a CT scan of her abdomen is conducted. While being transferred to her ward, she develops generalized itching and urticarial rashes, with facial angioedema. She becomes dyspneic. Her pulse is 110/min, the blood pressure is 80/50 mm Hg, and the respirations are 30/min. Her upper and lower extremities are pink and warm. What is the most appropriate management of this patient?", "answer": "Inject epinephrine 1:1000, followed by steroids and antihistamines", "options": {"A": "Perform IV resuscitation with colloids", "B": "Administer broad-spectrum IV antibiotics", "C": "Administer vasopressors (norepinephrine and dopamine)", "D": "Obtain an arterial blood gas analysis", "E": "Inject epinephrine 1:1000, followed by steroids and antihistamines"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 41-year-old man presents to the emergency department because of brownish discoloration of his urine for the last several days. The review of symptoms includes complaints of increasing abdominal girth, early satiety, and difficulty breathing on exertion. The past medical history includes essential hypertension for 19 years. The medication list includes lisinopril and hydrochlorothiazide. He had a right inguinal hernia repair when he was a teenager. He smokes 20–30 cigarettes daily for the last 21 years, and drinks alcohol socially. His father died of a hemorrhagic stroke at the age of 69 years. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 131/88 mm Hg, and pulse 82/min. The physical examination is positive for a palpable right upper quadrant mass. The abdominal ultrasound shows multiple bilateral kidney cysts and hepatic cysts. Which of the following is the most likely diagnosis?", "answer": "Autosomal dominant polycystic kidney disease", "options": {"A": "Renal cell carcinoma", "B": "Von Hippel-Lindau syndrome", "C": "Simple kidney cyst", "D": "Medullary sponge kidney", "E": "Autosomal dominant polycystic kidney disease"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 10-year-old boy presents to the emergency department with a swollen and painful elbow after accidentally bumping his arm into the kitchen table. His mom notes that he seems to bruise and bleed easily, but this is the first time he has had a swollen joint. She also remembers that her uncle had a bleeding disorder, but cannot remember the diagnosis. Physical exam reveals a warm and tender elbow joint, but is otherwise unremarkable. Based on clinical suspicion, a bleeding panel is ordered with the following findings:\n\nBleeding time: 3 minutes\nProthrombin time (PT): 13 seconds\nPartial thromboplastin time (PTT): 54 seconds\n\nWhich of the following treatments would most likely be effective in preventing further bleeding episodes for this patient?", "answer": "Factor VIII replacement", "options": {"A": "Factor VIII replacement", "B": "Intravenous immunoglobulin", "C": "Platelet administration", "D": "Vitamin K supplementation", "E": "von Williband factor replacement"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman is involved in a car accident and presents with an open fracture of the left femur and severe bleeding from the left femoral artery. No past medical history or current medications. Her blood pressure is 90/60 mm Hg, pulse is 110/min, and respirations are 21/min. On physical examination, the patient is lethargic, confused, and poorly responds to commands. Peripheral pulses are 1+ in the left lower extremity below the level of the knee and 2+ elsewhere. When she arrives at the hospital, a stat hemoglobin level shows 6 g/dL. Which of the following is most correct about the patient’s condition?", "answer": "This patient’s laboratory findings will likely demonstrate a normocytic anemia", "options": {"A": "Her reticulocyte count is expected to be lower than normal", "B": "Hemoglobin levels are expected to be low right after the accident", "C": "Hematocrit is expected to be low right after the accident", "D": "This patient will likely be diagnosed with iron deficiency anemia", "E": "This patient’s laboratory findings will likely demonstrate a normocytic anemia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old man is brought to the emergency department after an episode of hemoptysis. He has a chronic cough that is productive of copious sputum. Six years ago, he had a stroke that left him with difficulty swallowing. He smoked one pack of cigarettes daily for 40 years, but quit 2 years ago. His respirations are 25/min and labored. Physical examination shows digital clubbing. An x-ray of the chest shows tram track opacities in the lower lung fields. Which of the following is the most likely diagnosis?", "answer": "Bronchiectasis", "options": {"A": "Lung cancer", "B": "Chronic bronchitis", "C": "Aspiration pneumonia", "D": "Emphysema", "E": "Bronchiectasis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 14-year-old boy has undergone kidney transplantation due to stage V chronic kidney disease. A pre-transplantation serologic assessment showed that he is negative for past or present HIV infection, viral hepatitis, EBV, and CMV infection. He has a known allergy for macrolides. The patient has no complaints 1 day after transplantation. His vital signs include: blood pressure 120/70 mm Hg, heart rate 89/min, respiratory rate 17/min, and temperature 37.0°C (98.6°F). On physical examination, the patient appears to be pale, his lungs are clear on auscultation, heart sounds are normal, and his abdomen is non-tender on palpation. His creatinine is 0.65 mg/dL (57.5 µmol/L), GFR is 71.3 mL/min/1.73 m2, and urine output is 0.9 mL/kg/h. Which of the following drugs should be used in the immunosuppressive regimen in this patient?", "answer": "Basiliximab", "options": {"A": "Sirolimus", "B": "Basiliximab", "C": "Daclizumab", "D": "Belatacept", "E": "Omalizumab"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 2-year-old boy presents with multiple skin abscesses caused by Staphylococcus aureus. Past medical history is significant for recurrent infections by the same organism. The nitroblue tetrazolium (NBT) test demonstrates an inability to kill microbes. Which of the following defect is most likely responsible for the findings in this patient?", "answer": "Inability to generate the microbicidal respiratory burst", "options": {"A": "Deficiency of CD40L on activated T cells", "B": "Tyrosine kinase deficiency blocking B cell maturation", "C": "Inability to generate the microbicidal respiratory burst", "D": "Inability to fuse lysosomes with phagosomes", "E": "MHC class II deficiency"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 8-year-old boy presents to the physician with complaints that he is persistently experiencing sickness and clumsiness with multiple episodes of pneumonia and diarrhea. He also says that he has trouble seeing things well in the dark. Other symptoms include white patches (keratinized epithelium) on the sclerotic coat (protection and covering of the eyeball) and conjunctival dryness. Can you suggest the cause of these symptoms in this particular child?", "answer": "Deficiency of vitamin A", "options": {"A": "Vitamin B1 deficiency", "B": "Spinocerebellar ataxia (SCA) type 1", "C": "Autoimmune neutropenia", "D": "Deficiency of vitamin A", "E": "Congenital rubella"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 4-year-old boy is brought to the emergency department because of a 1-day history of pain and swelling of his left knee joint. He has not had any trauma to the knee. His family history is unremarkable except for a bleeding disorder in his maternal uncle. His temperature is 36.9°C (98.4°F). The left knee is erythematous, swollen, and tender; range of motion is limited. No other joints are affected. An x-ray of the knee shows an effusion but no structural abnormalities of the joint. Arthrocentesis is conducted. The synovial fluid is bloody. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Prolonged partial thromboplastin time", "options": {"A": "Elevated antinuclear antibody levels", "B": "Decreased platelet count", "C": "Prolonged prothrombin time", "D": "Prolonged partial thromboplastin time", "E": "Synovial fluid leukocytosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 30-year-old male visits you in the clinic complaining of chronic abdominal pain and diarrhea following milk intake. Gastrointestinal histology of this patient's condition is most similar to which of the following?", "answer": "No GI disease", "options": {"A": "Celiac disease", "B": "Crohns disease", "C": "Tropical sprue", "D": "No GI disease", "E": "Ulcerative colitis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old man presents to the Emergency Department after a window he was installing fell on him. The patient complains of left ocular pain, blurred vision, and obscured lower portion of the left visual field. The patient’s vital signs are as follows: blood pressure 140/80 mm Hg, heart rate 88/min, respiratory rate 14/min, and temperature 36.9℃ (98.4℉). On physical examination, he has multiple superficial lacerations on his face, arms, and legs. Examination of his right eye shows a superficial upper eyelid laceration. Examination of the left eye shows conjunctival hyperemia, peaked pupil, iridial asymmetry, hyphema, and vitreous hemorrhage. The fundus is hard to visualize due to the vitreous hemorrhage. The visual acuity is 20/25 in the right eye and difficult to evaluate in the left. Which of the following is a proper step to undertake in the diagnosis and management of this patient?", "answer": "Systemic administration of vancomycin and levofloxacin", "options": {"A": "Ultrasound examination of the left eye", "B": "Examination of the left eye with fluorescein", "C": "Examination of the fundus with a tropicamide application", "D": "Placing an ocular pad onto the affected eye", "E": "Systemic administration of vancomycin and levofloxacin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "While attending a holiday party, a 35-year-old widow noticed a male who physically resembled her deceased husband. She introduced herself and began a conversation with the male while making sure not to make mention of the resemblance. After the conversation, she felt feelings of affection and warmth to the male similar to how her husband made her feel. Which of the following best explains the widow's feelings towards the male?", "answer": "Transference", "options": {"A": "Transference", "B": "Countertransference", "C": "Sublimation", "D": "Projection", "E": "Identification"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old man presents to the office complaining of recent shortness of breath and fever. He has a history of a chronic cough which is progressively getting worse. His medical history is significant for hypertension and diabetes mellitus, both controlled with medication. He has been working in a sandblasting factory for over 3 decades. His temperature is 37.7°C (99.9°F), the blood pressure is 130/84 mm Hg, the pulse is 98/min, and the respiratory rate is 20/min. Chest X-ray reveals calcified hilar lymph nodes which look like an eggshell. This patient is at increased risk for which of the following conditions?", "answer": "Mycobacterium tuberculosis infection", "options": {"A": "Chronic obstructive pulmonary disease", "B": "Adenocarcinoma of the lung", "C": "Mesothelioma", "D": "Pulmonary embolism", "E": "Mycobacterium tuberculosis infection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 24-year-old woman presents to the ED with symptoms of pelvic inflammatory disease despite being previously treated with azithromycin for chlamydial infection. Based on your clinical understanding about the epidemiology of PID, you decide to obtain a gram stain which shows a gram-negative diplococci. What is the next step in order to confirm the identity of the organism described?", "answer": "Culture in Thayer-Martin media", "options": {"A": "Obtain an acid fast stain", "B": "Culture in Thayer-Martin media", "C": "Perform an RT-PCR", "D": "Culture in Bordet-Gengou agar", "E": "Culture in TCBS agar"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 29-year-old mother brings in her 2-week-old baby boy to a pediatrician because he has been having difficulty feeding. The mother reveals that she had no prenatal care during her pregnancy and gave birth at home without complications. She says that her son seems to be having difficulty sucking, and she occasionally sees breast milk coming out of the infant’s nose. Physical exam reveals that this patient has a gap between his oral and nasal cavities behind the incisive foramen. He is therefore prescribed specialized bottles and his mom is taught positional techniques to ensure better feeding. Failure to fuse which of the following structures is most likely responsible for this patient's disorder? ", "answer": "Palatine shelves with nasal septum", "options": {"A": "Maxillary and lateral nasal prominences", "B": "Maxillary and medial nasal prominences", "C": "Nasal septum with primary plates", "D": "Palatine shelves with nasal septum", "E": "Palatine shelves with primary plates"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 60-year-old woman presents to the dermatologist with a lesion on her lower eyelid. She noticed it a month ago and looked like a pimple. She says that it has been bleeding lately with minimal trauma which alarmed her. She says the lesion has not grown in size and is not associated with pain or pruritus. No significant past medical history. Physical examination reveals a 0.5 cm lesion that has a pearly appearance with telangiectasia and central ulceration and curled borders. The lesion is biopsied. Histopathology reveals peripheral palisading cells with large, hyperchromatic nuclei and a high nuclear: cytoplasmic ratio. Which of the following mechanisms best describes the most common mode of spread of this patient’s neoplasm?", "answer": "Local invasion via collagenase", "options": {"A": "Hematogenous spread", "B": "Seeding", "C": "Does not spread (tumor is typically benign)", "D": "Local invasion via collagenase", "E": "Lymphatic spread"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old man comes to the physician for the evaluation of a 2-month history of worsening fatigue and shortness of breath on exertion. While he used to be able to walk 4–5 blocks at a time, he now has to pause every 2 blocks. He also reports waking up from having to urinate at least once every night for the past 5 months. Recently, he has started using 2 pillows to avoid waking up coughing with acute shortness of breath at night. He has a history of hypertension and benign prostatic hyperplasia. His medications include daily amlodipine and prazosin, but he reports having trouble adhering to his medication regimen. His pulse is 72/min, blood pressure is 145/90 mm Hg, and respiratory rate is 20/min. Physical examination shows 2+ bilateral pitting edema of the lower legs. Auscultation shows an S4 gallop and fine bibasilar rales. Further evaluation is most likely to show which of the following pathophysiologic changes in this patient?", "answer": "Increased tone of efferent renal arterioles", "options": {"A": "Increased tone of efferent renal arterioles", "B": "Decreased alveolar surface tension", "C": "Decreased systemic vascular resistance", "D": "Increased left ventricular compliance", "E": "Increased potassium retention"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old girl presents to her primary care physician for a wellness checkup. The patient is currently doing well in school and plays soccer. She has a past medical history of childhood obesity that was treated with diet and exercise. The patient states that her menses have not changed, and they occur every 1 to 3 months. Her temperature is 99.5°F (37.5°C), blood pressure is 127/70 mmHg, pulse is 90/min, respirations are 13/min, and oxygen saturation is 98% on room air. The patient's BMI at this visit is 22.1 kg/m^2. On physical exam, the patient is in no distress. You note acne present on her face, shoulders, and chest. You also note thick, black hair on her upper lip and chest. The patient's laboratory values are seen as below.\n\nHemoglobin: 14 g/dL\nHematocrit: 42%\nLeukocyte count: 7,500/mm^3 with normal differential\nPlatelet count: 177,000/mm^3\n\nSerum:\nNa+: 137 mEq/L\nCl-: 101 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 24 mEq/L\nBUN: 27 mg/dL\nGlucose: 90 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.1 mg/dL\nTestosterone: 82 ng/dL\n17-hydroxyprogesterone: elevated\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following is associated with this patient's most likely diagnosis?", "answer": "Deficiency of 21-hydroxylase", "options": {"A": "Deficiency of 11-hydroxylase", "B": "Deficiency of 17-hydroxylase", "C": "Deficiency of 21-hydroxylase", "D": "Insulin resistance", "E": "Malignancy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A medical technician is trying to isolate a pathogen from the sputum sample of a patient. The sample is heat fixed to a slide then covered with carbol fuchsin stain and heated again. After washing off the stain with clean water, the slide is covered with sulfuric acid. The sample is rinsed again and stained with methylene blue. Microscopic examination shows numerous red organisms. Which of the following is the most likely isolated pathogen?", "answer": "Nocardia asteroides", "options": {"A": "Tropheryma whipplei", "B": "Rickettsia rickettsii", "C": "Nocardia asteroides", "D": "Cryptococcus neoformans", "E": "Staphylococcus aureus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old woman with 45,X syndrome comes to the physician because of diarrhea for 4 months. She also reports bloating, nausea, and abdominal discomfort that persists after defecation. For the past 6 months, she has felt tired and has been unable to do her normal chores. She went on a backpacking trip across Southeast Asia around 7 months ago. She is 144 cm (4 ft 9 in) tall and weighs 40 kg (88 lb); BMI is 19 kg/m2. Her blood pressure is 110/60 mm Hg in the upper extremities and 80/40 mm Hg in the lower extremities. Examination shows pale conjunctivae and angular stomatitis. Abdominal examination is normal. Laboratory studies show:\nHemoglobin 9.1 mg/dL\nLeukocyte count 5100/mm3\nPlatelet count 200,000/mm3\nMean corpuscular volume 67 μmm3\nSerum\nNa+ 136 mEq/L\nK+ 3.7 mEq/L\nCl- 105 mEq/L\nGlucose 89 mg/dL\nCreatinine 1.4 mg/dL\nFerritin 10 ng/mL\nIgA tissue transglutaminase antibody positive\nBased on the laboratory studies, a biopsy for confirmation of the diagnosis is suggested, but the patient is unwilling to undergo the procedure. Which of the following is the most appropriate next step in management of this patient's gastrointestinal symptoms?\"", "answer": "Gluten-free diet", "options": {"A": "Metronidazole therapy", "B": "Avoid milk products", "C": "Intravenous immunoglobulin therapy", "D": "Gluten-free diet", "E": "Trimethoprim-sulfamethaxazole therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man presents with severe fatigue and fever. His past medical history is significant for a recent history of mononucleosis from which he fully recovered 8 weeks ago. On physical examination, the patient seems pale. A chest radiograph shows multiple enlarged mediastinal lymph nodes. A biopsy of one of the enlarged mediastinal lymph nodes is performed and shows the presence of multinucleated cells with an ‘owl-eye’ appearance in a hypocellular background. This patient’s most likely condition is very aggressive and associated with a very poor prognosis. Which of the following is the most likely diagnosis in this patient?", "answer": "Lymphocyte-depleted lymphoma", "options": {"A": "Lymphocyte-depleted lymphoma", "B": "Diffuse large B cell lymphoma", "C": "Follicular lymphoma", "D": "Extranodal marginal zone lymphoma", "E": "Nodular lymphocyte-predominant lymphoma"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old woman presents to the emergency department with chest discomfort and fatigue. She reports that her symptoms began approximately 1 week ago and are associated with shortness of breath, swelling of her legs, and worsening weakness. She’s been having transitory fevers for about 1 month and denies having similar symptoms in the past. Medical history is significant for systemic lupus erythematosus (SLE) treated with hydroxychloroquine. She had a SLE flare approximately 2 weeks prior to presentation, requiring a short course of prednisone. Physical exam was significant for a pericardial friction rub. An electrocardiogram showed widespread ST-segment elevation and PR depression. After extensive work-up, she was admitted for further evaluation, treatment, and observation. Approximately 2 days after admission she became unresponsive. Her temperature is 100°F (37.8°C), blood pressure is 75/52 mmHg, pulse is 120/min, and respirations are 22/min. Heart sounds are muffled. Which of the following is a clinical finding that will most likely be found in this patient?", "answer": "Jugular venous distension", "options": {"A": "Decreased systolic blood pressure by 8 mmHg with inspiration", "B": "Jugular venous distension", "C": "Pericardial knock", "D": "Unequal blood pressure measurements between both arms", "E": "Warm extremities"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 28-year-old woman is brought to the physician because of progressive difficulty walking, slowed speech, and a tremor for the past 5 months. Her grandfather died of bleeding esophageal varices at the age of 42 years. She does not drink alcohol. She is alert and oriented but has a flat affect. Her speech is slurred and monotonous. Examination shows a broad-based gait and a low-frequency tremor of her left hand. Abdominal examination shows hepatosplenomegaly. A photograph of the patient's right eye is shown. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Low serum ceruloplasmin concentration", "options": {"A": "Skin deposits of lipid-laden macrophages", "B": "Increased number of CAG repeats", "C": "Positive anti-hepatitis B virus IgG antibodies", "D": "Low serum ceruloplasmin concentration", "E": "Destruction of lobular bile ducts on liver biopsy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 65-year-old man presents to his primary care provider with excessive fatigue, weight loss, and multiple small bruises on his arms and abdomen. These symptoms started several months ago. He reports worsening fatigue and a 20-pound (9 kg) weight loss in the past month. Past medical history is significant for an asymptomatic lymphocytosis noted 6 months ago on a yearly physical. On review of systems, he denies chest pain, difficulty breathing, swelling in the extremities, or change in bowel habits. Vitals include: temperature 37.0°C (98.6°F), blood pressure 110/75 mm Hg, pulse 99/min, respirations 20/min, and oxygen saturation 91% on room air. On physical exam, the patient is listless. The cardiac exam is normal. Lungs are clear to auscultation. The abdominal exam is significant for mild splenomegaly. Scleral icterus is present and there is prominent generalized non-tender lymphadenopathy. Which of the following laboratory findings is best associated with this patient’s condition?", "answer": "Positive direct Coombs tests", "options": {"A": "Increased serum complement", "B": "Decreased serum ferritin", "C": "Positive direct Coombs tests", "D": "Degmacytes on peripheral blood smear", "E": "Codocytes on peripheral blood smear"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 42-year-old homeless man is brought to the emergency room after he was found unconscious in a park. He has alcohol on his breath and is known to have a history of chronic alcoholism. A noncontrast CT scan of the head is normal. The patient is treated for acute alcohol intoxication and admitted to the hospital. The next day, the patient demands to be released. His vital signs are a pulse 120/min, a respiratory rate 22/min, and blood pressure 136/88 mm Hg. On physical examination, the patient is confused, agitated, and sweating profusely, particularly from his palms. Generalized pallor is present. What is the mechanism of action of the drug recommended to treat this patient’s most likely condition?", "answer": "It increases the frequency of GABA-gated chloride channel opening.", "options": {"A": "It increases the duration of GABA-gated chloride channel opening.", "B": "It increases the frequency of GABA-gated chloride channel opening.", "C": "It decreases the frequency of GABA-gated chloride channel opening.", "D": "It activates the GABA receptors by binding at the GABA binding site.", "E": "It decreases the duration of GABA-gated chloride channel opening."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy was brought in by his parents for undescended testes. The physical examination showed an absence of the left testis in the scrotum. Inguinal swelling was noted on the left side and was surgically corrected. Which of the following conditions will most likely occur in the later stages of his life?", "answer": "Testicular cancer", "options": {"A": "Spermatocele", "B": "Torsion testis", "C": "Varicocele", "D": "Epididymitis", "E": "Testicular cancer"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 70-year-old woman is brought to the emergency department 1 hour after being found unconscious in her apartment by her neighbor. No medical history is currently available. Her temperature is 37.2°C (99.0°F), pulse is 120/min, respirations are 18/min, and blood pressure is 70/50 mm Hg. Laboratory studies show a glomerular filtration rate of 70 mL/min/1.73 m2 (N > 90) and an increased filtration fraction. Which of the following is the most likely cause of this patient's findings?", "answer": "Profuse diarrhea", "options": {"A": "Pyelonephritis", "B": "Nephrolithiasis", "C": "Profuse diarrhea", "D": "Salicylate poisoning", "E": "Multiple myeloma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old woman presents to the clinic complaining of fatigue for the past 2 weeks. She reports that it is difficult for her to do strenuous tasks such as lifting heavy boxes at the bar she works at. She denies any precipitating factors, weight changes, nail changes, dry skin, chest pain, abdominal pain, or urinary changes. She is currently trying out a vegetarian diet for weight loss and overall wellness. Besides heavier than usual periods, the patient is otherwise healthy with no significant medical history. A physical examination demonstrates conjunctival pallor. Where in the gastrointestinal system is the most likely mineral that is deficient in the patient absorbed?", "answer": "Duodenum", "options": {"A": "Duodenum", "B": "Ileum", "C": "Jejunum", "D": "Large intestine", "E": "Stomach"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman comes to the emergency department because of worsening severe pain, swelling, and stiffness in her right knee for the past 2 days. She recently started running 2 miles, 3 times a week in an attempt to lose weight. She has type 2 diabetes mellitus and osteoporosis. Her mother has rheumatoid arthritis. She drinks one to two glasses of wine daily. She is sexually active with multiple partners and uses condoms inconsistently. Current medications include metformin and alendronate. She is 161 cm (5 ft 3 in) tall and weighs 74 kg (163 lb); BMI is 29 kg/m2. Her temperature is 38.3°C (100.9°F), pulse is 74/min, and blood pressure is 115/76 mm Hg. She appears to be in discomfort and has trouble putting weight on the affected knee. Physical examination shows a 2-cm, painless ulcer on the plantar surface of the right toe. The right knee is swollen and tender to palpation. Arthrocentesis of the right knee with synovial fluid analysis shows a cell count of 55,000 WBC/μL with 77% polymorphonuclear (PMN) cells. Which of the following is the most likely underlying cause of this patient's presenting condition?", "answer": "Hematogenous spread of infection", "options": {"A": "Direct innoculation of infectious agent", "B": "Autoimmune response to bacterial infection", "C": "Occult meniscal tear", "D": "Hematogenous spread of infection", "E": "Intra-articular deposition of urate crystals"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A four-week-old female is evaluated in the neonatal intensive care unit for feeding intolerance with gastric retention of formula. She was born at 25 weeks gestation to a 32-year-old gravida 1 due to preterm premature rupture of membranes at 24 weeks gestation. The patient’s birth weight was 750 g (1 lb 10 oz). She required resuscitation with mechanical ventilation at the time of delivery, but she was subsequently extubated to continuous positive airway pressure (CPAP) and then weaned to nasal cannula. The patient was initially receiving both parenteral nutrition and enteral feeds through a nasogastric tube, but she is now receiving only continuous nasogastric formula feeds. Her feeds are being advanced to a target weight gain of 20-30 g per day. Her current weight is 1,350 g (2 lb 16 oz). The patient’s temperature is 97.2°F (36.2°C), blood pressure is 72/54 mmHg, pulse is 138/min, respirations are 26/min, and SpO2 is 96% on 4L nasal cannula. On physical exam, the patient appears lethargic. Her abdomen is soft and markedly distended. Digital rectal exam reveals stool streaked with blood in the rectal vault.\n\nWhich of the following abdominal radiographs would most likely be seen in this patient?", "answer": "D", "options": {"A": "A", "B": "B", "C": "C", "D": "D", "E": "E"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old Caucasian woman presents to her primary care provider complaining about difficulties while swallowing with fatigability and occasional palpitations for the past few weeks. Her personal history is relevant for bariatric surgery a year ago and a long list of allergies which includes peanuts, penicillin, and milk protein. Physical examination is unremarkable except for pale skin and mucosal surfaces, koilonychia, and glossitis. Which of the following descriptions would you expect to find in an endoscopy?", "answer": "Luminal eccentric membranes", "options": {"A": "Hiatus hernia", "B": "Luminal protruding concentric diaphragms", "C": "Luminal eccentric membranes", "D": "Changes in the epithelial lining of the esophagus", "E": "Pharyngeal pouch"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old man is admitted to the hospital because of a 2-day history of right-sided weakness and dysphagia. He is diagnosed with a thrombotic stroke and treatment with aspirin is initiated. A videofluoroscopic swallowing study is performed to determine his ability to swallow safely; he is found to be at increased risk of aspiration. Consequently, he is ordered not to have any food or liquids by mouth. A Dobhoff feeding tube is placed, tube feedings are ordered, and the patient starts receiving tube feedings. Shortly after, he develops a cough and dyspnea. An x-ray of the chest shows opacification of the right lower lobe and that the end of the Dobhoff tube is in his right lung instead of his stomach. Which of the following would most likely have prevented this medical error from occurring?", "answer": "Checklist", "options": {"A": "Two patient identifiers", "B": "Closed-loop communication", "C": "Checklist", "D": "Mortality and morbidity review", "E": "Fishbone diagram"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 20-year-old woman presents with shortness of breath and chest pain for 1 week. She says the chest pain is severe, sharp in character, and aggravated upon deep breathing. She says she becomes short of breath while walking upstairs in her home or with any type of exertion. She says she frequently feels feverish and fatigued. No significant past medical history and no current medications. Review of systems is significant for a weight loss of 4.5 kg (10.0 lb) over the past month and joint pain in her wrists, hands, and knees. Vital signs are within normal limits. On physical examination, there is a pink rash over her face which is aggravated by sunlight (shown in the image). There are decreased breath sounds on the right. A chest radiograph reveals evidence of a right-sided pleural effusion. Routine urinalysis and urine dipstick are normal. Serum antinuclear antibody (ANA) and anti-double-stranded DNA levels are positive. The patient is started on prednisone therapy and 2 weeks later her CBC is obtained and compared to the one on admission:\nOn admission\nLeukocytes 8,000/mm3\nNeutrophils 60%\nLymphocytes 23%\nEosinophils 2%\nBasophils 1%\nMonocyte 5%\nHemoglobin 10 g/dL\nCreatinine 0.8 mg/dL\nBUN 15 mg/dL\n2 weeks later\nLeukocytes 13,000/mm3\nNeutrophils 90%\nLymphocytes 8%\nEosinophils 0%\nBasophils 0%\nMonocyte 1%\nHemoglobin 12g/dL\nCreatinine 0.8 mg/dL\nBUN 15 mg/dL\nWhich of the following best describes the most likely mechanism that accounts for the difference between these 2 complete blood counts (CBCs)?", "answer": "Downregulation of neutrophil adhesion molecules", "options": {"A": "Upregulation of cellular adhesion molecules in the endothelium", "B": "Apoptosis of neutrophils", "C": "Redistribution of neutrophils in the lymph nodes", "D": "Phagocytosis by neutrophils", "E": "Downregulation of neutrophil adhesion molecules"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 44-year-old woman presents to her primary care physician because she has been experiencing shortness of breath and fatigue over the past week. In addition, she has noticed that her eyelids appear puffy and her lower extremities have become swollen. Laboratory tests reveal protein and fatty casts in her urine. Based on these findings, a kidney biopsy is obtained and has a granular appearance on immunofluorescence with subepithelial deposits on electron microscopy. Which of the following is associated with the most likely cause of this patient's symptoms?", "answer": "Phospholipase A2 receptor antibodies", "options": {"A": "Diabetes", "B": "Onset in childhood", "C": "Phospholipase A2 receptor antibodies", "D": "Plasma cell dyscrasias", "E": "Sickle cell disease"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old man presents to his primary care physician complaining of subjective fever, cough, and night sweats. He states that over the past 2 months he has “not felt like myself.” He has lost 12 lbs over this time period. Two weeks ago, he started experiencing night sweats and cough. This morning he decided to take his temperature and reports it was “high.” He has a history of HIV and admits to inconsistently taking his anti-retrovirals. A chest radiograph reveals a cavitary lesion in the left upper lobe. An interferon-gamma release assay is positive, and the patient is started on appropriate antimicrobial therapy. A month later he is seen in clinic for follow-up. Lab work is obtained, as shown below:\n\nLeukocyte count: 11,000/mm^3 with normal differential\nHemoglobin: 9.2 g/dL\nPlatelet count: 400,000/mm^3\nMean corpuscular volume (MCV): 75 µm^3\n\nBased on these results, a peripheral smear is sent and shows Pappenheimer bodies. Which of the following is the most accurate test for the patient’s diagnosis?", "answer": "Prussian blue staining", "options": {"A": "Genetic testing", "B": "Hemoglobin electrophoresis", "C": "Iron studies", "D": "Methylmalonic acid level", "E": "Prussian blue staining"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "The prison doctor sees a 25-year-old man for some minor injuries sustained during a recent lunchroom brawl. The patient has a long history of getting into trouble. During his interview, he seems very charming and carefully deflects all responsibility to others and gets irritable and hostile once probed on the issues. He is married and has 2 young children for whom he does not pay child support. Which of the following details is most critical for diagnosing this patient’s condition?", "answer": "Childhood history", "options": {"A": "Childhood history", "B": "History of substance abuse", "C": "Family history", "D": "Evidence of lack of remorse", "E": "Criminal record"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 52-year-old man presents to his physician with a chief concern of not feeling well. The patient states that since yesterday he has experienced nausea, vomiting, diarrhea, general muscle cramps, a runny nose, and aches and pains in his muscles and joints. The patient has a past medical history of obesity, chronic pulmonary disease, lower back pain, and fibromyalgia. His current medications include varenicline, oxycodone, and an albuterol inhaler. The patient is requesting antibiotics and a refill on his current medications at this visit. He works at a local public school and presented with a similar chief complaint a week ago, at which time he had his prescriptions refilled. You have also seen several of his coworkers this past week and sent them home with conservative measures. Which of the following is the best next step in management?", "answer": "Methadone", "options": {"A": "Azithromycin", "B": "Methadone", "C": "Metronidazole", "D": "Oseltamivir", "E": "Supportive therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 60-year-old woman presents to the physician with a 2-day history of fever and painful swelling of the left knee. She was diagnosed with rheumatoid arthritis about 15 years ago and has a 7-year history of diabetes mellitus. Over the past year, she has been admitted to the hospital twice for acute, painful swelling of the knees and hands. She is on insulin therapy and takes methotrexate, metformin, aspirin, and prednisolone 5 mg/day. Her temperature is 38.5°C (101.3°F), pulse is 86/min, respirations are 14/min, and blood pressure is 125/70 mm Hg. A finger-stick glucose test shows 230 mg/dL. Her left knee is diffusely swollen, warm, and painful on both active and passive motion. There is evidence of deformity in several small joints of the hands and feet without any acute swelling or pain. Physical examination of the lungs, abdomen, and perineum shows no abnormalities. The synovial fluid analysis shows the following:\nColor turbid, purulent, gray\nViscosity reduced\nWBC 25,000/µL–250,000/µL\nNeutrophils > 90%\nCrystals may be present (presence indicates coexistence, but does not rule out infection)\nWhich of the following is the most appropriate initial pharmacotherapy in this patient?", "answer": "Intravenous vancomycin", "options": {"A": "Intra-articular ceftriaxone", "B": "Intra-articular triamcinolone acetonide", "C": "Intravenous methylprednisolone", "D": "Intravenous vancomycin", "E": "Oral ciprofloxacin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 26-year-old woman at 30 weeks 2 days of gestational age is brought into the emergency room following a seizure episode. Her medical records demonstrate poorly controlled gestational hypertension. Following administration of magnesium, she is taken to the operating room for emergency cesarean section. Her newborn daughter’s APGAR scores are 7 and 9 at 1 and 5 minutes, respectively. The newborn is subsequently taken to the NICU for further management and monitoring. Ten days following birth, the baby begins to refuse formula feedings and starts having several episodes of bloody diarrhea despite normal stool patterns previously. Her temperature is 102.2°F (39°C), blood pressure is 84/53 mmHg, pulse is 210/min, respirations are 53/min, and oxygen saturation is 96% on room air. A physical examination demonstrates a baby in mild respiratory distress and moderate abdominal distention. What do you expect to find in this patient?", "answer": "Gas within the walls of the small or large intestine on radiograph", "options": {"A": "Absence of ganglion cells on rectal biopsy", "B": "Double bubble sign on abdominal radiograph", "C": "High levels of cow's milk-specific IgE", "D": "Gas within the walls of the small or large intestine on radiograph", "E": "Positive blood cultures of group B streptococcus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 12-year-old boy presents with progressive clumsiness and difficulty walking. He walks like a 'drunken-man' and has experienced frequent falls. He was born at term and has gone through normal developmental milestones. His vaccination profile is up to date. He denies fever, chills, nausea, vomiting, chest pain, and shortness of breath. He has no history of alcohol use or illicit drug use. His elder brother experienced the same symptoms. The physical examination reveals normal higher mental functions. His extraocular movements are normal. His speech is mildly dysarthric. His muscle tone and strength in all 4 limbs are normal. His ankle reflexes are absent bilaterally with positive Babinski’s signs. Both vibration and proprioception are absent bilaterally. When he is asked to stand with his eyes closed and with both feet close together, he sways from side to side, unable to stand still. X-ray results show mild scoliosis. Electrocardiogram results show widespread T-wave inversions. His fasting blood glucose level is 143 mg/dL. What is the most likely diagnosis?", "answer": "Friedreich’s ataxia", "options": {"A": "Ataxia-telangiectasia", "B": "Charcot-Marie-Tooth disease", "C": "Duchene muscular dystrophy", "D": "Friedreich’s ataxia", "E": "Myotonic dystrophy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man presents to the emergency department because of an excruciating headache that started suddenly after he got home from work. He also reports having double vision. Specifically, in the last week he almost got into two car accidents with vehicles that \"came out of nowhere\" while he was trying to merge on the highway. Physical examination is notable for ptosis of the left eye, which is also inferiorly and laterally deviated. The patient is treated emergently and then started on a hormone replacement in order to avoid life-threatening post-treatment complications. The patient's current presentation was associated with a pathologic process that existed for several months prior to this event. Which of the following symptoms could this patient have experienced as part of that pre-existing pathology?", "answer": "Increased hat size", "options": {"A": "Gastric ulcers", "B": "Hypoglycemia", "C": "Hyperkalemia", "D": "Increased hat size", "E": "Kidney stones"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 49-year-old man is brought to the emergency department by his wife because he is vomiting blood. His wife reports that he has been nauseous for the past day and that he has had 2 episodes of vomiting bright red blood over the past 2 hours. He has never experienced this before. He has not had any bloody stool, melena, or abdominal pain. He was diagnosed with alcoholic cirrhosis 6 months ago. He drank approximately 1 liter of vodka over the past day, which is typical for him. He takes no medications. He is confused and disoriented to place and time. Physical examination shows ascites. Vital signs are within normal limits. His hemoglobin concentration is 9.5 g/dL. Intravenous fluid resuscitation is begun. He starts to vomit bright red blood again intermittently, which continues for 10 minutes. When vital signs are measured again, his pulse is 95/min and blood pressure is 109/80 mm/Hg. Which of the following is the most appropriate initial step in management?", "answer": "Perform endotracheal intubation", "options": {"A": "Place nasogastric tube", "B": "Perform endotracheal intubation", "C": "Administer intravenous octreotide", "D": "Perform upper endoscopy", "E": "Administer cryoprecipitate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old woman is undergoing work up for progressive weakness. She reports that at the end of the work day, her \"eyelids droop\" and her \"eyes cross,\" but in the morning she feels \"ok.\" She reports that her legs feel heavy when she climbs the stairs of her house to go to sleep at night. As part of her work up, the physician has her hold her gaze toward the ceiling, and after a minute, her lids become ptotic. She is given an IV medication and her symptoms resolve, but return 10 minutes later. Which of the following medications was used in the diagnostic test performed for this patient?", "answer": "Edrophonium", "options": {"A": "Physostigmine", "B": "Neostigmine", "C": "Pyridostigmine", "D": "Edrophonium", "E": "Echothiophate"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A drug that inhibits mRNA synthesis has the well-documented side effect of red-orange body fluids. For which of the following is this drug used as monotherapy?", "answer": "Neisseria meningitidis prophylaxis", "options": {"A": "Mycobacterium avium intracellulare infection", "B": "Methicillin-resistant staphylococcus aureus infection", "C": "Neisseria meningitidis prophylaxis", "D": "Brucellosis", "E": "It is inappropriate to use this drug as monotherapy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old man is brought to the emergency department due to chest pain and shortness of breath for the last 2 hours. He describes the chest pain as squeezing in nature and radiating towards his left arm. It is associated with nausea and sweating. He has a similar history in the past, which is mostly aggravated with strenuous activities and relieved with sublingual nitroglycerin. He has a history of uncontrolled diabetes and hypercholesterolemia for the last 10 years. His last HbA1c was 8.0 %. His blood pressure is 150/90 mm Hg, pulse rate is 90/min, respiratory rate is 20/min, and temperature is 36.8°C (98.3°F). Oxygen saturation in room air is 98%. ECG shows ST-segment elevation in leads I, II, and aVF. He is being prepared for coronary angioplasty. Elevation in which of the following enzymes is most significant in the diagnosis of this patient?", "answer": "Troponin I", "options": {"A": "Aspartate transaminase ", "B": "Lactate dehydrogenase-1", "C": "Troponin I", "D": "Myoglobin", "E": "Creatine kinase – MB"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-year-old boy is brought by his mother to his pediatrician for “skin growths.” His mother reports that she started noticing small lumps arising from the patient’s lips and eyelids several months ago. She also notes that he seems to suffer from frequent constipation and appears “weaker” than many of his peers. The boy’s past medical history is unremarkable. His maternal aunt, maternal uncle, and maternal grandmother have a history of colorectal cancer and his father and paternal grandmother have a history of thyroid cancer. His height and weight are in the 85th and 45th percentiles, respectively. His temperature is 99°F (37.1°C), blood pressure is 110/65 mmHg, pulse is 90/min, and respirations are 18/min. On examination, he has an elongated face with protruding lips. There are numerous sessile painless nodules on the patient’s lips, tongue, and eyelids. This patient’s condition is most strongly associated with a mutation in which of the following genes?", "answer": "RET", "options": {"A": "c-KIT", "B": "MEN1", "C": "NF1", "D": "NF2", "E": "RET"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 50-year-old man presents with a 3-day history of painful peeling of his skin. He says he initially noted small erythematous spots on areas of his neck, but this quickly spread to his torso, face, and buttocks to form flaccid blisters and areas of epidermal detachment involving > 40% of his total body surface area. He describes the associated pain as severe, burning, and generalized over his entire body. The patient does recall having an episode with similar symptoms 10 years ago after taking an unknown antibiotic for community-acquired pneumonia, but the symptoms were nowhere near this severe. He denies any fever, chills, palpitations, dizziness, or trouble breathing. Past medical history is significant for a urinary tract infection (UTI) diagnosed 1 week ago for which he has been taking ciprofloxacin. His vital signs include: blood pressure, 130/90 mm Hg; temperature, 37.7℃ (99.9℉); respiratory, rate 22/min; and pulse, 110/min. On physical examination, the patient is ill-appearing and in acute distress due to pain. The epidermis sloughing involves areas of the face, back, torso, buttocks, and thighs bilaterally, and its appearance is shown in the exhibit (see image). Nikolsky sign is positive. Laboratory findings are unremarkable. Which of the following is the next best diagnostic step in this patient?", "answer": "Skin biopsy and histopathologic analysis", "options": {"A": "Direct immunofluorescence on perilesional biopsy", "B": "Indirect immunofluorescence on perilesional biopsy", "C": "Blood cultures", "D": "Skin biopsy and histopathologic analysis", "E": "PCR for serum staphylococcal exfoliative toxin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old woman comes to the physician for a pre-employment examination. Her current medications include an oral contraceptive and a daily multivitamin. Physical examination is unremarkable. Serum studies show calcium of 11.8 mg/dL, phosphorus of 2.3 mg/dL, and parathyroid hormone level of 615 pg/mL. A 24-hour urine collection shows a low urinary calcium level. Which of the following is the most likely underlying cause of this patient’s laboratory findings?", "answer": "Defect in calcium-sensing receptors", "options": {"A": "Hyperplasia of parathyroid chief cells", "B": "Impaired phosphate excretion", "C": "Defect in calcium-sensing receptors", "D": "IL-1-induced osteoclast activation", "E": "Extrarenal calcitriol production"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 5-year-old boy presents to his pediatrician with weakness. His father observed that his son seemed less energetic at daycare and kindergarten classes. He was becoming easily fatigued from mild play. His temperature is 98°F (37°C), blood pressure is 90/60 mmHg, pulse is 100/min, and respirations are 20/min. Physical exam reveals pale conjunctiva, poor skin turgor and capillary refill, and cervical and axillary lymphadenopathy with assorted bruises throughout his body. A complete blood count reveals the following:\n\nLeukocyte count: 3,000/mm^3\nSegmented neutrophils: 30%\nBands: 5%\nEosinophils: 5%\nBasophils: 10%\nLymphocytes: 40%\nMonocytes: 10%\n\nHemoglobin: 7.1 g/dL\nHematocrit: 22%\nPlatelet count: 50,000/mm^3\n\nThe most specific diagnostic assessment would most likely show which of the following?", "answer": "Bone marrow biopsy with > 25% lymphoblasts", "options": {"A": "Bone marrow biopsy with > 25% lymphoblasts", "B": "Flow cytometry with positive terminal deoxynucleotidyl transferase staining", "C": "Fluorescence in situ hybridization analysis with 9:22 translocation", "D": "Fluorescence in situ hybridization analysis with 12:21 translocation", "E": "Peripheral blood smear with > 50% lymphoblasts"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old woman with a history of diabetes and hypertension accidentally overdoses on antiarrhythmic medication. Upon arrival in the ER, she is administered a drug to counteract the effects of the overdose. Which of the following matches an antiarrhythmic with its correct treatment in overdose?", "answer": "Esmolol and glucagon", "options": {"A": "Quinidine and insulin", "B": "Encainide and epinephrine", "C": "Propafenone and glucose", "D": "Esmolol and glucagon", "E": "Sotalol and norepinephrine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "You are seeing a patient in clinic who presents with complaints of weakness. Her physical exam is notable for right sided hyperreflexia, as well as the finding in video V. Where is the most likely location of this patient's lesion?", "answer": "Internal capsule", "options": {"A": "Subthalamic nucleus", "B": "Lateral geniculate nucleus", "C": "Postcentral gyrus", "D": "Neuromuscular junction", "E": "Internal capsule"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 8-year-old female presents to her pediatrician with nasal congestion. Her mother reports that the patient has had nasal congestion and nighttime cough for almost two weeks. The patient’s 3-year-old brother had similar symptoms that began around the same time and have since resolved. The patient initially seemed to be improving, but four days ago she began developing worsening nasal discharge and fever to 102.6°F (39.2°C) at home. Her mother denies any change in appetite. The patient denies sore throat, ear pain, and headache. She is otherwise healthy. In the office, her temperature is 102.2°F (39.0°C), blood pressure is 96/71 mmHg, pulse is 128/min, and respirations are 18/min. On physical exam, the nasal turbinates are edematous and erythematous. She has a dry cough. Purulent mucous can be visualized dripping from the posterior nasopharynx. Her maxillary sinuses are tender to palpation.\n\nWhich of the following organisms is most likely to be causing this patient’s current condition?", "answer": "Moraxella catarrhalis", "options": {"A": "Adenovirus", "B": "Moraxella catarrhalis", "C": "Pseudomonas aeruginosa", "D": "Staphylococcus aureus", "E": "Streptococcus pyogenes"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old female comes to the physician because of fever and worsening cough for the past 4-days. She has had several episodes of otitis media, sinusitis, and an intermittent cough productive of green sputum for the past 2-years. She has also noticed some streaks of blood in the sputum lately. Her temperature is 38°C (100.4°F). Auscultation of the chest reveals crackles and rhonchi bilaterally. Heart sounds cannot be heard along the left lower chest. A CT scan of the chest reveals bronchiectasis and dextrocardia. Which of the following additional findings is most likely in this patient?", "answer": "Delayed tubal ovum transit", "options": {"A": "Delayed tubal ovum transit", "B": "NADPH oxidase deficiency", "C": "Decreased immunoglobulin levels", "D": "Defective interleukin-2 receptor gamma chain", "E": "Increased sweat chloride levels\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-day-old boy is brought to the emergency room with a fever. He was born to a G1P1 mother at 39 weeks gestation via vaginal delivery. The mother underwent all appropriate prenatal care and was discharged from the hospital 1 day after birth. The boy has notable skin erythema around the anus with some serosanguinous fluid. The umbilical stump is present. The patient is discharged from the emergency room with antibiotics. He returns to the emergency room at 32 days of age and his mother reports that he has been clutching his left ear. The left tympanic membrane appears inflamed and swollen. The umbilical stump is still attached and is indurated, erythematous, and swollen. The boy's temperature is 99°F (37.2°C), blood pressure is 100/60 mmHg, pulse is 130/min, and respirations are 20/min. A complete blood count is shown below:\n\nHemoglobin: 14.0 g/dL\nHematocrit: 42%\nLeukocyte count: 16,000/mm^3 with normal differential\nPlatelet count: 190,000/mm^3\n\nA deficiency in which of the following compounds is most likely the cause of this patient's condition?", "answer": "LFA-1 integrin", "options": {"A": "IL-12 receptor", "B": "Immunoglobulin A", "C": "LFA-1 integrin", "D": "NADPH oxidase", "E": "Tapasin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "The boy is admitted to the pediatric intensive care unit for closer monitoring. Peripheral venous access is established. He is treated with IV isotonic saline and started on an insulin infusion. This patient is at the highest risk for which of the following conditions in the next 24 hours?", "answer": "Cerebral edema", "options": {"A": "Cerebral edema", "B": "Intrinsic kidney injury", "C": "Cognitive impairment", "D": "Deep venous thrombosis", "E": "Hyperkalemia"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 70-year-old man presents to the physician with a 1-month history of severe fatigue. During this time, he has unintentionally lost 2 kg (4.4 lb). Currently, he takes no medications other than aspirin for occasional knee pain. He does not smoke or drink alcohol. His vital signs are within the normal range. On physical examination, the conjunctivae are pale. Petechiae are present on the distal lower extremities and on the soft and hard palates. Palpation reveals bilateral painless cervical lymphadenopathy. Examination of the lungs, heart, and abdomen shows no abnormalities. Which of the following factors in this patient’s history or laboratory findings would most likely indicate a good prognosis?", "answer": "Translocation t(15;17)", "options": {"A": "History of myelodysplastic syndrome", "B": "Leukocyte count > 100,000/mm3", "C": "Philadelphia chromosome", "D": "Prior treatment with cytotoxic agents", "E": "Translocation t(15;17)"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 11-month-old boy presents to his pediatrician with severe wheezing, cough, and fever of 38.0°C (101.0°F). Past medical history is notable for chronic diarrhea since birth, as well as multiple pyogenic infections. The mother received prenatal care, and delivery was uneventful. Both parents, as well as the child, are HIV-negative. Upon further investigation, the child is discovered to have Pneumocystis jirovecii pneumonia, and the appropriate treatment is begun. Additionally, a full immunologic check-up is ordered. Which of the following profiles is most likely to be observed in this patient?", "answer": "Increased IgM and decreased IgA, IgG, and IgE", "options": {"A": "Increased IgM and decreased IgA, IgG, and IgE", "B": "Increased IgE", "C": "Decreased IgM and increased IgE and IgA", "D": "Decreased IgE, IgM, IgA, and IgG", "E": "Increased IgE and decreased IgA and IgM"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 76-year-old man presents after an acute onset seizure. He lives in a retirement home and denies any previous history of seizures. Past medical history is significant for a hemorrhagic stroke 4 years ago, and type 2 diabetes, managed with metformin. His vital signs include: blood pressure 80/50 mm Hg, pulse 80/min, and respiratory rate 19/min. On physical examination, the patient is lethargic. Mucous membranes are dry. A noncontrast CT of the head is performed and is unremarkable. Laboratory findings are significant for the following:\nPlasma glucose 680 mg/dL\npH 7.37\nSerum bicarbonate 17 mEq/L\nEffective serum osmolality 350 mOsm/kg\nUrinary ketone bodies negative\nWhich of the following was the most likely trigger for this patient’s seizure?", "answer": "Reduced fluid intake", "options": {"A": "Reduced fluid intake", "B": "Unusual increase in physical activity", "C": "Inappropriate insulin therapy", "D": "Metformin side effects", "E": "Concomitant viral infection"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 64-year-old woman comes to the physician because of a 7.2-kg (16-lb) weight loss over the past 6 months. For the last 4 weeks, she has also had intermittent constipation and bloating. Four months ago, she spent 2 weeks in Mexico with her daughter. She has never smoked. She drinks one glass of wine daily. She appears thin. Her temperature is 38.3°C (101°F), pulse is 80/min, and blood pressure is 136/78 mm Hg. The lungs are clear to auscultation. The abdomen is distended and the liver is palpable 4 cm below the right costal margin with a hard, mildly tender nodule in the left lobe. Test of the stool for occult blood is positive. Serum studies show:\nAlkaline phosphatase 67 U/L\nAST 65 U/L\nALT 68 U/L\nHepatitis B surface antigen negative\nHepatitis C antibody negative\nA contrast-enhanced CT scan of the abdomen is shown. Which of the following is the most likely diagnosis?\"", "answer": "Metastatic colorectal cancer", "options": {"A": "Hepatic echinococcal cysts", "B": "Cholangiocarcinoma", "C": "Hepatocellular carcinoma", "D": "Metastatic colorectal cancer", "E": "Cirrhosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old African American man presents to his primary care physician with a chief complaint of leg swelling. He says that the swelling began about 2 weeks ago and he cannot recall anything that may have provoked the episode. Otherwise he has had joint pain, headaches, frothy urine, and some tingling in his fingers and toes though he doesn't feel that any of this is related to his swelling. He denies any shortness of breath, back pain, or skull pain. His past medical history is significant for mild rheumatoid arthritis, diabetes, and hypertension all of which are well controlled. Physical exam reveals 3+ pitting edema in his legs bilaterally. A chest radiograph reveals mild enlargement of the cardiac shadow. Urinalysis reveals 3+ protein and casts with a cross appearance under polarized light. A renal biopsy is taken with a characteristic finding seen only under polarized light. Which of the following is associated with the most likely cause of this patient's edema?", "answer": "Elevated levels of IL-6", "options": {"A": "Abnormally shaped red blood cells", "B": "Altered kappa to lambda ratio", "C": "Antibodies to phospholipase A2 receptor", "D": "Elevated levels of hemoglobin A1c", "E": "Elevated levels of IL-6"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 10-month-old girl is brought to the clinic by her mother with skin lesions on her chest. The mother says that she noticed the lesions 24 hours ago and that they have not improved. The patient has no significant past medical history. She was born at term by spontaneous transvaginal delivery with no complications, is in the 90th percentile on her growth curve, and has met all developmental milestones. Upon physical examination, several skin-colored umbilicated papules are visible. Which of the following is the most appropriate treatment of this patient's likely diagnosis?", "answer": "Cryotherapy or podophyllotoxin (0.15% topically)", "options": {"A": "Acyclovir", "B": "Topical antifungal therapy", "C": "Wide-spectrum antibiotics", "D": "Cryotherapy or podophyllotoxin (0.15% topically)", "E": "Multivitamin supplementation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old female patient is brought to the emergency department after her daughter noticed she has been having meaningless speech. When assessing the patient, she calls the chair a table, and at times would make up new words. She does not appear to be aware of her deficit, and is carrying on an empty conversation. Her speech is fluent, but with paraphasic errors. Her repetition is impaired. On physical examination, a right upper quadrant field-cut is appreciated, with impairment in comprehension and repetition. Which of the following structures is most likely involved in this patient’s presentation?", "answer": "Superior temporal gyrus", "options": {"A": "Arcuate fasciculus", "B": "Inferior frontal gyrus", "C": "Superior temporal gyrus", "D": "Acuate fasciculus, inferior frontal gyrus, and superior temporal gyrus", "E": "Frontal lobe, sparing Broadmann's area 44 and 45"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A researcher has identified a chemical compound that she expects may contribute to the development of colorectal cancer. She designs an experiment where she exposes 70 mice to a diet containing this compound with another 50 mice in a control group that was fed a regular diet. After 9 months, the mice were evaluated for tumor development at necropsy. In total, 14 mice in the experimental group developed colorectal tumor burden, and 1 mouse in the control group developed tumors. Based on this experiment, what risk of colorectal cancer can be attributable to this chemical compound?", "answer": "18.0%", "options": {"A": "2.0%", "B": "12.5%", "C": "18.0%", "D": "20.0%", "E": "22.0%"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man presents to his primary care physician for a rash. He states that for the past several days he has felt burning and itching around his eye. Yesterday, he noticed that a rash had formed. Review of systems is notable for mild diarrhea for the past week. The patient has a past medical history of diabetes, asthma, seasonal allergies, and hypertension. He is not currently taking any medications. Physical exam is notable for a vesicular rash surrounding the orbit. Which of the following is the best next step in management?", "answer": "Acyclovir", "options": {"A": "Acyclovir", "B": "Oral steroids", "C": "Removal of gluten containing products from the diet", "D": "Topical muciporin", "E": "Topical steroids"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 66-year-old woman presents to the emergency department after a fall 4 hours ago. She was on her way to the bathroom when she fell to the ground and lost consciousness. Although she regained consciousness within one minute, she experienced lightheadedness for almost half an hour. She has experienced on-and-off dizziness for the past 2 weeks whenever she tries to stand. She has a history of type 2 diabetes mellitus, hypertension, hypercholesterolemia, and chronic kidney disease secondary to polycystic kidneys. Her medications include aspirin, bisoprolol, doxazosin, erythropoietin, insulin, rosuvastatin, and calcium and vitamin D supplements. She has a blood pressure of 111/74 mm Hg while supine and 84/60 mm Hg on standing, the heart rate of 48/min, the respiratory rate of 14/min, and the temperature of 37.0°C (98.6°F). CT scan of the head is unremarkable. Electrocardiogram reveals a PR interval of 250 ms. What is the next best step in the management of this patient?", "answer": "Stop antihypertensive medicines", "options": {"A": "Electroencephalogram", "B": "Holter monitoring", "C": "Start anti-epileptics", "D": "Stop antihypertensive medicines", "E": "Tilt table testing"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A group of researchers wish to develop a clinical trial assessing the efficacy of a specific medication on the urinary excretion of amphetamines in intoxicated patients. They recruit 50 patients for the treatment arm and 50 patients for the control arm of the study. Demographics are fairly balanced between the two groups. The primary end points include (1) time to recovery of mental status, (2) baseline heart rate, (3) urinary pH, and (4) specific gravity. Which medication should they use in order to achieve a statistically significant result positively favoring the intervention?", "answer": "Ascorbic acid", "options": {"A": "Potassium citrate", "B": "Ascorbic acid", "C": "Aluminum hydroxide", "D": "Sodium bicarbonate", "E": "Tap water"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old G6P1 woman presents to the obstetrician for a prenatal visit. She is 8 weeks pregnant. She has had 4 spontaneous abortions in the past, all during the first trimester. She tells you she is worried about having another miscarriage. She has been keeping to a strictly organic diet and takes a daily prenatal vitamin. She used to smoke a pack a day since she was 16 but quit after her first miscarriage. On a previous visit following fetal loss, the patient tested positive for VDRL and negative for FTA-ABS. Labs are drawn, as shown below:\n\nLeukocyte count: 7,800/mm^3\nPlatelet count: 230,000/mm^3\nHemoglobin: 12.6 g/dL\nProthrombin time: 13 seconds\nActivated partial thromboplastin time: 48 seconds\nInternational normalized ratio: 1.2\n\nWhich of the following is the best next step in management?", "answer": "Low molecular weight heparin", "options": {"A": "Corticosteroids", "B": "Low molecular weight heparin", "C": "Intramuscular benzathine penicillin G", "D": "Vitamin K", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old man presents to the clinic complaining of chronic joint pain and fatigue for the past 2 months. The patient states that he usually has pain in one of his joints that resolve but then seems to move to another joint. The patient notes no history of trauma but states that he has experienced some subjective fevers over that time. He works as a logger and notes that he’s heard that people have also had these symptoms in the past, but that he does not anyone who is currently experiencing them. What is the most likely etiologic agent of this patient’s disease?", "answer": "A spirochete", "options": {"A": "A gram-negative diplococci", "B": "A spirochete", "C": "A gram-positive, spore-forming rod", "D": "A gram-positive cocci in chains", "E": "ssDNA virus of the Parvoviridae family"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old man presents to an outpatient clinic with chronic fatigue and bumps on his neck, right axilla, and groin. Upon questioning, he reveals he frequently visits Japan on business and is rather promiscuous on his business trips. He denies use of barrier protection. On examination, there is generalized lymphadenopathy. Routine lab work reveals abnormal lymphocytes on peripheral smear. The serum calcium is 12.2 mg/dL. Which of the following viruses is associated with this patient’s condition?", "answer": "Human T-lymphotropic virus 1", "options": {"A": "Human immunodeficiency virus", "B": "Hepatitis C virus", "C": "Hepatitis B virus", "D": "Human T-lymphotropic virus 2", "E": "Human T-lymphotropic virus 1"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 22-year-old primigravida is admitted to the obstetrics ward with leg swelling at 35 weeks gestation. She denies any other symptoms. Her pregnancy has been uneventful and she was compliant with the recommended prenatal care. Her vital signs were as follows: blood pressure, 168/95 mm Hg; heart rate, 86/min; respiratory rate, 16/min; and temperature, 36.7℃ (98℉). The fetal heart rate was 141/min. The physical examination was significant for 2+ pitting edema of the lower extremity. A dipstick test shows 1+ proteinuria. On reassessment 15 minutes later without administration of an antihypertensive, her blood pressure was 141/88 mm Hg, and the fetal heart rate was 147/min. A decision was made to observe the patient and continue the work-up without initiating antihypertensive therapy. Which of the following clinical features would make the suspected diagnosis into a more severe form?", "answer": "Blood pressure of 165/90 mm Hg reassessed 4 hours later", "options": {"A": "24-hour urinary protein of 5 g/L", "B": "Blood pressure of 165/90 mm Hg reassessed 4 hours later", "C": "Hematocrit of 0.55", "D": "Platelet count 133,000/μL", "E": "Serum creatinine 0.98 mg/dL"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old girl is brought to the physician because of progressive intermittent pain and swelling in both knees and right ankle and wrist for 3 months. She has been taking acetaminophen and using ice packs, both of which relieved her symptoms. The affected joints feel \"\"stuck” and difficult to move when she wakes up in the morning, but she can move them freely after a few minutes. She has also occasional mild eye pain that resolves spontaneously. Five months ago she was diagnosed with upper respiratory tract infection that resolved without treatment. Vital signs are within normal limits. Examination shows that the affected joints are swollen, erythematous, and tender to touch. Slit-lamp examination shows an anterior chamber flare with signs of iris inflammation bilaterally. Laboratory studies show:\nHemoglobin 12.6 g/dl\nLeukocyte count 8,000/mm3\nSegmented neutrophils 76%\nEosinophils 1%\nLymphocytes 20%\nMonocytes 3%\nPlatelet count 360,000/mm3\nErythrocyte sedimentation rate 36 mm/hr\nSerum\nAntinuclear antibodies 1:320\nRheumatoid factor negative\nWhich of the following is the most likely diagnosis?\"", "answer": "Oligoarticular juvenile idiopathic arthritis", "options": {"A": "Psoriatic juvenile arthritis", "B": "Seronegative polyarticular juvenile idiopathic arthritis", "C": "Acute lymphocytic leukemia", "D": "Systemic juvenile idiopathic arthritis", "E": "Oligoarticular juvenile idiopathic arthritis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 65-year-old male presents to your office complaining of worsening shortness of breath. He has experienced shortness of breath on and off for several years, but is noticing that it is increasingly more difficult. Upon examination, you note wheezing and cyanosis. You conduct pulmonary function tests, and find that the patient's FEV1/FVC ratio is markedly decreased. What is the most likely additional finding in this patient?", "answer": "Increased erythropoietin", "options": {"A": "Decreased serum bicarbonate", "B": "Increased erythropoietin", "C": "Nasal polyps", "D": "Increased IgE", "E": "Pleural effusion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man presents to the emergency department with nausea, palpitations, and lightheadedness after consuming a drink prepared from the leaves of yellow oleander (Thevetia peruviana). He had read somewhere that such a drink is healthy. As he liked the taste, he consumed 3 glasses of the drink before the symptoms developed. He also vomited twice. There is no past medical history suggestive of any significant medical condition. On physical examination, he is disoriented. The temperature is 36.5°C (97.8°F), the pulse is 140/min and irregular, the blood pressure is 94/58 mm Hg, and the respiratory rate is 14/min. Auscultation of the heart reveals an irregularly irregular heartbeat, while auscultation of the lungs does not reveal any significant abnormalities. The abdomen is soft and the pupillary reflexes are intact. An electrocardiogram shows peaked T waves. A botanist confirms that yellow oleander leaves contain cardiac glycosides. In addition to controlling the airway, breathing, and circulation with supportive therapy, which of the following medications is indicated?", "answer": "Digoxin immune Fab", "options": {"A": "Procainamide", "B": "Digoxin immune Fab", "C": "Atropine", "D": "Propranolol", "E": "Quinidine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 1-year-old boy presents to pediatrics clinic for a well-child visit. He has no complaints. He has a cleft palate and an abnormal facial appearance. He has been riddled with recurrent infections and is followed by cardiology for a ventricular septal defect (VSD). Vital signs are stable, and the patient's physical exam is benign. If this patient's medical history is part of a larger syndrome, what might one also discover that is consistent with the manifestations of this syndrome?", "answer": "A positive Chvostek's sign", "options": {"A": "Kidney stones", "B": "B-cell deficiency", "C": "A positive Chvostek's sign", "D": "A shortened QT Interval", "E": "Hypoactive deep tendon reflexes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 46-year-old woman presents to the emergency department complaining of bloody diarrhea, fatigue, and confusion. A few days earlier she went to a fast-food restaurant for a college reunion party. Her friends are experiencing similar symptoms. Laboratory tests show anemia, thrombocytopenia, and uremia. Lactate dehydrogenase (LDH) is raised while haptoglobin is decreased. Peripheral blood smears show fragmented red blood cells (RBCs). Coombs tests are negative. Which of the following is the responsible organism?", "answer": "E. coli", "options": {"A": "Entamoeba histolytica", "B": "E. coli", "C": "Campylobacter jejuni", "D": "Shigella", "E": "Salmonella"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A couple brings their 1-year-old child to a medical office for a follow-up evaluation of his small, empty scrotum. The scrotum has been empty since birth and the physician asked them to follow up with a pediatrician. There are no other complaints. The immunization history is up to date and his growth and development have been excellent. On examination, he is a playful, active child with a left, non-reducible, non-tender inguinal mass, an empty and poorly rugated hemiscrotal sac, and a testis within the right hemiscrotal sac. Which of the following hormones would likely be deficient in this patient by puberty if the condition is left untreated?", "answer": "Inhibin", "options": {"A": "Prolactin", "B": "LH", "C": "Inhibin", "D": "Testosterone", "E": "FSH"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old woman presents to her physician with a persistent and debilitating cough which began 3 weeks ago, and chest pain accompanied by shortness of breath for the past week. Past medical history is significant for breast carcinoma 10 years ago treated with mastectomy, chemotherapy and radiation, a hospitalization a month ago for pneumonia that was treated with antibiotics, hypertension, and diabetes mellitus. Medications include chlorthalidone and metformin. She does not smoke but her husband has been smoking 3 packs a day for 30 years. Today her respiratory rate is 20/min and the blood pressure is 150/90 mm Hg. Serum Na is 140 mmol/L, serum K is 3.8 mmol/L and serum Ca is 12.2 mg/dL. A chest X-ray (shown in image) is performed. Which of the following is the most likely diagnosis?", "answer": "Squamous cell carcinoma lung", "options": {"A": "Bacterial pneumonia", "B": "Viral pneumonia", "C": "Small cell carcinoma lung", "D": "Squamous cell carcinoma lung", "E": "Tuberculosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An investigator is developing a drug for muscle spasms. The drug inactivates muscular contraction by blocking the site where calcium ions bind to the myocyte actin filament. Which of the following is the most likely site of action of this drug?", "answer": "Troponin C", "options": {"A": "Myosin-binding site", "B": "Myosin head", "C": "Ryanodine receptor", "D": "Acetylcholine receptor", "E": "Troponin C"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old woman is brought to the emergency department by ambulance after an unexpected fall at home 1 hour ago. She was resuscitated at the scene by paramedics before being transferred to the hospital. She has a history of ischemic heart disease and type 2 diabetes mellitus. She has not taken any sedative medications. Her GCS is 6. She is connected to a mechanical ventilator. Her medical records show that she signed a living will 5 years ago, which indicates her refusal to receive any type of cardiopulmonary resuscitation, intubation, or maintenance of life support on mechanical ventilation. Her son, who has a durable power-of-attorney for her healthcare decisions, objects to the discontinuation of mechanical ventilation and wishes that his mother be kept alive without suffering in the chance that she might recover. Which of the following is the most appropriate response to her son regarding his wishes for his mother?", "answer": "“Based on her wishes, mechanical ventilation must be discontinued.”", "options": {"A": "“Based on her wishes, mechanical ventilation must be discontinued.”", "B": "“Further management decisions will be referred to the hospital’s ethics committee.”", "C": "“She may be eligible for hospice care.”", "D": "“The opinion of her primary care physician must be obtained regarding further steps in management.”", "E": "“We will take every measure necessary to prolong her life.”"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 54-year-old male carpenter accidentally amputated his right thumb while working in his workshop 30 minutes ago. He reports that he was cutting a piece of wood, and his hand became caught up in the machinery. He is calling the emergency physician for advice on how to transport his thumb and if it is necessary. Which of the following is the best information for this patient?", "answer": "Wrap thumb in saline-moistened, sterile gauze and place in sterile bag", "options": {"A": "Place thumb directly into cooler of ice", "B": "Place thumb in cup of cold milk", "C": "Wrap thumb in sterile gauze and submerge in a cup of saline", "D": "Wrap thumb in saline-moistened, sterile gauze and place in sterile bag", "E": "There is no need to save the thumb"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old diabetic man presents to your office for routine follow-up. One year ago, the patient’s hemoglobin A1C was 7.2% and the patient was encouraged to modify his diet and increase exercise. Six months ago, the patient’s HA1C was 7.3%, and you initiated metformin. Today, the patient has no complaints. For which of the following co-morbidities would it be acceptable to continue metformin?", "answer": "Mild chronic obstructive pulmonary disease", "options": {"A": "Hepatitis C infection", "B": "Mild chronic obstructive pulmonary disease", "C": "Recent diagnosis of NYHA Class II congestive heart failure", "D": "Prior hospitalization for alcoholic hepatitis", "E": "Headache and family history of brain aneurysms requiring CT angiography"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old boy is brought to the emergency department with difficulty breathing. His mother reports that he developed a fever last night and began to have trouble breathing this morning. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is unvaccinated (conscientious objection by the family) and is meeting all developmental milestones. At the hospital, his vitals are temperature 39.8°C (103.6°F), pulse 122/min, respiration rate 33/min, blood pressure 110/66 mm Hg, and SpO2 93% on room air. On physical examination, he appears ill with his neck hyperextended and chin protruding. His voice is muffled and is drooling. The pediatrician explains that there is one particular bacteria that commonly causes these symptoms. At what age should the patient have first received vaccination to prevent this condition from this particular bacteria?", "answer": "At 2-months-old", "options": {"A": "At birth", "B": "At 2-months-old", "C": "At 6-months-old", "D": "Between 9- and 12-months-old", "E": "Between 12- and 15-months-old"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man comes to the physician two weeks after a blood pressure of 160/92 mm Hg was measured at a routine health maintenance examination. Subsequent home blood pressure measurements since the last visit have been: 159/98 mm Hg, 161/102 mm Hg, and 152/95 mm Hg. Over the past 3 years, the patient has had a 10-kg (22-lb) weight gain. He has type 2 diabetes mellitus. He does not follow any specific diet; he usually eats sandwiches at work and fried chicken or burger for dinner. He says that he has been struggling with a stressful project at work recently. His mother was diagnosed with hypertension at the age of 45. The patient's only medication is metformin. His pulse is 82/min, and blood pressure now is 158/98 mm Hg. The patient is 178 cm (5 ft 10 in) tall and weighs 133 kg (293 lb); BMI is 42 kg/m2. Physical examination shows no other abnormalities except for significant central obesity. Fasting serum studies show:\nTotal cholesterol 220 mg/dL\nHDL-cholesterol 25 mg/dL\nTriglycerides 198 mg/dL\nGlucose 120 mg/dL\nWhich of the following is the most important factor in the development of this patient's condition?\"", "answer": "Resistance to insulin", "options": {"A": "Release of proinflammatory cytokines", "B": "Accumulation of fat in visceral tissue", "C": "Resistance to insulin", "D": "Increased dietary salt intake", "E": "Elevation of blood lipids"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old man is brought to the emergency department because of increasing shortness of breath that began while playing outdoors with his grandson. He has a history of asthma but does not take any medications for it. On arrival, he is alert and oriented. He is out of breath and unable to finish his sentences. His pulse is 130/min, respirations are 23/min and labored, and blood pressure is 110/70 mm Hg. Physical examination shows nasal flaring and sternocleidomastoid muscle use. Pulmonary exam shows poor air movement bilaterally but no wheezing. Cardiac examination shows no abnormalities. Oxygen is administered via non-rebreather mask. He is given three albuterol nebulizer treatments, inhaled ipratropium, and intravenous methylprednisolone. The patient is confused and disoriented. Arterial blood gas analysis shows:\npH 7.34\nPco2 44 mm Hg\nPo2 54 mm Hg\nO2 saturation 87%\nWhich of the following is the most appropriate next step in management?\"", "answer": "Endotracheal intubation", "options": {"A": "Endotracheal intubation", "B": "Intravenous theophylline therapy", "C": "Continuous albuterol nebulizer therapy", "D": "Intravenous magnesium sulfate therapy", "E": "Flexible bronchoscopy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 52-year-old male with ischemic cardiomyopathy presents to his cardiologist for worsening shortness of breath on exertion. He denies any recent episodes of chest pain and has been compliant with his medications, which include metoprolol, lisinopril, spironolactone, and furosemide. The patient’s vitals signs are as follows: Temperature is 98.7 deg F (37.1 deg C), blood pressure is 163/78 mmHg, pulse is 92/min, respirations are 14/min, and oxygen saturation is 98% on room air. A repeat echocardiogram reveals a stable LVEF of 25-35%. The physician decides to start hydralazine and isosorbide dinitrate. Which of the following is true regarding this medication combination?", "answer": "Decreases the volume and work placed on the left ventricle", "options": {"A": "Has anti-inflammatory properties to reduce the risk of coronary artery thrombosis", "B": "Increases the volume of blood that enters the heart to improve ventricular contraction", "C": "Improves symptoms but do not have an overall mortality benefit in patients with congestive heart failure", "D": "Decreases the volume and work placed on the left ventricle", "E": "Has positive effects on cardiac remodeling"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 16-year-old girl comes to the physician with her mother because of intermittent abdominal cramps, fatigue, and increased urination over the past 3 months. She has no history of serious illness. She reports that she has not yet had her first menstrual period. Her mother states that she receives mostly A and B grades in school and is very active in school athletics. Her mother has type 2 diabetes mellitus and her maternal aunt has polycystic ovary syndrome. Her only medication is a daily multivitamin. The patient is 150 cm (4 ft 11 in) tall and weighs 50 kg (110 lb); BMI is 22.2 kg/m2. Vital signs are within normal limits. A grade 2/6 early systolic murmur is heard best over the pulmonic area and increases with inspiration. The abdomen is diffusely tender to palpation and a firm mass is felt in the lower abdomen. Breast and pubic hair development are at Tanner stage 5. Which of the following is the most appropriate next step in management?", "answer": "Serum β-hCG", "options": {"A": "Pelvic ultrasound", "B": "Fasting glucose and lipid panel", "C": "Serum fT4", "D": "Serum β-hCG", "E": "Karyotyping"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old woman presents to the clinic because of fever, joint pain, and a rash on her lower extremities. She admits to intravenous drug use. Physical examination reveals palpable petechiae and purpura on her lower extremities. Laboratory results reveal a negative antinuclear antibody, positive rheumatoid factor, and positive serum cryoglobulins. Which of the following underlying conditions in this patient is responsible for these findings?", "answer": "Hepatitis C infection", "options": {"A": "Dermatomyositis", "B": "Hepatitis B infection", "C": "Hepatitis C infection", "D": "HIV infection", "E": "Systemic lupus erythematosus (SLE)"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old woman with a 1-year history of medically-managed Graves disease visits her endocrinologist to discuss her desire to become pregnant and whether pregnancy is safe with her medications. Her temperature is 98.4°F (36.9°C), blood pressure is 110/66 mmHg, pulse is 78/min, respirations are 12/min. The endocrinologist advises that the patient may pursue pregnancy, but first needs to be switched to a new medication for her Graves disease. Which of the following is a possible side effect in this new medication that is not a risk in her old medication?", "answer": "Fulminant hepatic necrosis", "options": {"A": "Agranulocytosis", "B": "Aplastic anemia", "C": "Fulminant hepatic necrosis", "D": "Skin rash", "E": "Thyroid storm"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old man comes to the physician because of a 5-day history of progressively worsening shortness of breath and fatigue. He has smoked 1 pack of cigarettes daily for 30 years. His pulse is 96/min, respirations are 26/min, and blood pressure is 100/60 mm Hg. An x-ray of the chest is shown. Which of the following is the most likely cause of this patient's findings?", "answer": "Left ventricular failure", "options": {"A": "Left ventricular failure", "B": "Tricuspid regurgitation", "C": "Acute respiratory distress syndrome", "D": "Pulmonary embolism", "E": "Interstitial pneumonia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old woman comes to the physician because of left leg pain and swelling for 1 day. She has had two miscarriages but otherwise has no history of serious illness. Physical examination shows stiff, swollen finger joints. The left calf circumference is larger than the right and there is a palpable cord in the left popliteal fossa. Laboratory studies show a prothrombin time of 12 seconds and an activated partial thromboplastin time of 51 seconds. Which of the following is most likely to confirm the diagnosis?", "answer": "Anti-β2 glycoprotein antibodies", "options": {"A": "Anti-nuclear antibodies", "B": "Anti-ribonucleoprotein antibodies", "C": "Anti-cyclical citrullinated peptide antibodies", "D": "Anti-β2 glycoprotein antibodies", "E": "Anti-synthetase antibodies"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old male presents to the emergency with abdominal pain. He reports he has had abdominal pain associated with meals for several months and has been taking over the counter antacids as needed, but experienced significant worsening pain one hour ago in the epigastric region. The patient reports the pain radiating to his shoulders. Vital signs are T 38, HR 120, BP 100/60, RR 18, SpO2 98%. Physical exam reveals diffuse abdominal rigidity with rebound tenderness. Auscultation reveals hypoactive bowel sounds. Which of the following is the next best step in management?", "answer": "Chest radiograph", "options": {"A": "Abdominal ultrasound", "B": "Chest radiograph", "C": "Abdominal CT scan", "D": "12 lead electrocardiogram", "E": "Admission and observation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 31-year-old woman presents to your office with one week of recurrent fevers. The highest temperature she recorded was 101°F (38.3°C). She recently returned from a trip to Nigeria to visit family and recalls a painful bite on her right forearm at that time. Her medical history is significant for two malarial infections as a child. She is not taking any medications. On physical examination, her temperature is 102.2°F (39°C), blood pressure is 122/80 mmHg, pulse is 80/min, respirations are 18/min, and pulse oximetry is 99% on room air. She has bilateral cervical lymphadenopathy and a visible, enlarged, mobile posterior cervical node. Cardiopulmonary and abdominal examinations are unremarkable. She has an erythematous induration on her right forearm. The most likely cause of this patient's symptoms can be treated with which of the following medications?", "answer": "Suramin and melarsoprol", "options": {"A": "Chloroquine", "B": "Primaquine", "C": "Atovaquone and azithromycin", "D": "Suramin and melarsoprol", "E": "Sulfadiazine and pyrimethamine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 36-year-old man presents with soreness and dryness of the oral mucosa for the past 3 weeks. No significant past medical history. The patient reports that he has had multiple bisexual partners over the last year and only occasionally uses condoms. He denies any alcohol use or history of smoking. The patient is afebrile and his vital signs are within normal limits. On physical examination, there is a lesion noted in the oral cavity, which is shown in the exhibit. Which of the following is the next best step in the treatment of this patient?", "answer": "Change the patient’s toothbrush and improve oral hygiene", "options": {"A": "Change the patient’s toothbrush and improve oral hygiene", "B": "HAART therapy", "C": "Nystatin", "D": "Surgical excision", "E": "Topical corticosteroids"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old woman presents to her primary care physician for an annual checkup. She reports that she has been feeling well and has no medical concerns. Her past medical history is significant for childhood asthma but she has not experienced any symptoms since she was a teenager. Physical exam reveals a 1-centimeter hard mobile mass in the left upper outer quadrant of her breast. A mammogram was performed and demonstrated calcifications within the mass so a biopsy was obtained. The biopsy shows acinar proliferation with intralobular fibrosis. Which of the following conditions is most likely affecting this patient?", "answer": "Sclerosing adenosis", "options": {"A": "Cystic hyperplasia", "B": "Fibroadenoma", "C": "Infiltrating ductal carcinoma", "D": "Invasive lobular carcinoma", "E": "Sclerosing adenosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to his pediatrician’s office because of prolonged ear pulling and discomfort. The condition started a week ago and his parents are concerned that he has developed another ear infection. He has had multiple minor respiratory tract infections with productive cough and ear infections over the last year; he has also been hospitalized once with community-acquired pneumonia. During his last ear infection, there was some discussion of myringotomy. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Today, the vital signs include: temperature 39.0°C (102.0°F), blood pressure 100/65 mm Hg, heart rate 110/min, and respiratory rate 30/min. His left ear is tender and appears red and irritated. Examination with an otoscope reveals a swollen canal and a bulging tympanic membrane. A review of previous medical records reveals the following chest X-ray taken 2 months ago. What is the underlying cause of his recurrent infections?", "answer": "Kartagener syndrome", "options": {"A": "Cystic fibrosis", "B": "Common variable immune deficiency", "C": "X-linked agammaglobulinemia", "D": "Otitis media", "E": "Kartagener syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old woman, gravida 2, para 1, at 12 weeks' gestation comes to the physician for a prenatal visit. She feels well. Pregnancy and vaginal delivery of her first child were uncomplicated. Five years ago, she was diagnosed with hypertension but reports that she has been noncompliant with her hypertension regimen. The patient does not smoke or drink alcohol. She does not use illicit drugs. Medications include methyldopa, folic acid, and a multivitamin. Her temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 145/90 mm Hg. Physical examination shows no abnormalities. Laboratory studies, including serum glucose level, and thyroid-stimulating hormone concentration, are within normal limits. The patient is at increased risk of developing which of the following complications?", "answer": "Abruptio placentae", "options": {"A": "Uterine rupture", "B": "Spontaneous abortion", "C": "Polyhydramnios", "D": "Abruptio placentae", "E": "Placenta previa"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old woman, gravida 1, para 0, at 10 weeks' gestation comes to the physician for a prenatal examination. She has no history of significant medical illness. Physical examination shows a uterus consistent with a 10-week gestation. Cell-free fetal DNA testing shows a karyotype of 47,XXY. If the fetus's condition had not been diagnosed until puberty, which of the following sets of hormonal changes would most likely be found at that time?\n $$$ Follicle-stimulating hormone %%% Luteinizing hormone %%% Testosterone %%% Estrogen $$$", "answer": "↑ ↑ ↓ ↑", "options": {"A": "↑ ↑ ↓ ↑", "B": "↓ ↓ ↓ ↓", "C": "↑ ↑ normal normal", "D": "↑ ↑ ↑ ↓", "E": "↓ ↓ normal ↑"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 44-year-old man is brought to the emergency department 45 minutes after being involved in a high-speed motor vehicle collision in which he was the restrained driver. On arrival, he has left hip and left leg pain. His pulse is 135/min, respirations are 28/min, and blood pressure is 90/40 mm Hg. Examination shows an open left tibial fracture with active bleeding. The left lower extremity appears shortened, flexed, and internally rotated. Femoral and pedal pulses are decreased bilaterally. Massive transfusion protocol is initiated. An x-ray of the pelvis shows an open pelvis fracture and an open left tibial mid-shaft fracture. A CT scan of the head shows no abnormalities. Laboratory studies show:\nHemoglobin 10.2 g/dL\nLeukocyte count 10,000/mm3\nPlatelet count <250,000/mm3\nProthrombin time 12 sec\nPartial thromboplastin time 30 sec\nSerum\nNa+ 125 mEq/L\nK+ 4.5 mEq/L\nCl- 98 mEq/L\nHCO3- 25 mEq/L\nUrea nitrogen 18 mg/dL\nCreatinine 1.2 mg/dL\nThe patient is taken emergently to interventional radiology for exploratory angiography and arterial embolization. Which of the following is the most likely explanation for this patient's hyponatremia?\"", "answer": "Physiologic ADH (vasopressin) secretion", "options": {"A": "Physiologic aldosterone secretion", "B": "Pathologic aldosterone secretion", "C": "Adrenal crisis", "D": "Pathologic ADH (vasopressin) secretion", "E": "Physiologic ADH (vasopressin) secretion"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 67-year old woman is brought to the emergency department after she lost consciousness while at home. Her daughter was with her at the time and recalls that her mother was complaining of a diffuse headache and nausea about 2 hours before the incident. The daughter says that her mother has not had any recent falls and was found sitting in a chair when she lost consciousness. She has hypertension. Current medications include amlodipine, a daily multivitamin, and acetaminophen. She has smoked 1/2 pack of cigarettes daily for the past 45 years. Her pulse is 92/min, respirations are 10/min, and blood pressure is 158/100 mm Hg. She is disoriented and unable to follow commands. Examination shows nuchal rigidity. She has flexor posturing to painful stimuli. Fundoscopic examination is notable for bilateral vitreous hemorrhages. Laboratory studies are within normal limits. An emergent non-contrast CT scan of the head is obtained and shows a diffuse hemorrhage at the base of the brain that is largest over the left hemisphere. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Ruptured saccular aneurysm", "options": {"A": "Ruptured mycotic aneurysm", "B": "Ruptured saccular aneurysm", "C": "Intracranial arteriovenous malformation", "D": "Intracranial arterial dissection", "E": "Spinal arteriovenous malformation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old man with liver cirrhosis presents to his primary care physician complaining of increased abdominal girth and early satiety. He drinks 2–4 glasses of wine with dinner and recalls having had abnormal liver enzymes in the past. Vital signs include a temperature of 37.1°C (98.7°F), blood pressure of 110/70 mm Hg, and a pulse of 75/min. Physical examination reveals telangiectasias, mild splenomegaly, palpable firm liver, and shifting dullness. Liver function is shown:\nTotal bilirubin 3 mg/dL\nAspartate aminotransferase (AST) 150 U/L\nAlanine aminotransferase (ALT) 70 U/L\nTotal albumin 2.5 g/dL\nAbdominal ultrasonography confirms the presence of ascites. Diagnostic paracentesis is performed and its results are shown:\nPolymorphonuclear cell count 10 cells/mm\nAscitic protein 1 g/dL\nWhich of the following best represent the mechanism of ascites in this patients?", "answer": "High sinusoidal pressure", "options": {"A": "Peritoneal carcinomatosis", "B": "Serositis", "C": "Peritoneal tuberculosis", "D": "High sinusoidal pressure", "E": "Pancreatic disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old man is brought to the emergency department with a stab wound to his chest. The wound is treated in the emergency room. Three months later he develops a firm 4 x 3 cm nodular mass with intact epithelium over the site of the chest wound. On local examination, the scar is firm, non-tender, and there is no erythema. The mass is excised and microscopic examination reveals fibroblasts with plentiful collagen. Which of the following processes is most likely related to the series of events mentioned above?", "answer": "Keloid scar formation", "options": {"A": "Foreign body response from suturing", "B": "Poor wound healing from diabetes mellitus", "C": "Keloid scar formation", "D": "Staphylococcal wound infection", "E": "Development of a fibrosarcoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old man presents to the emergency department for chest pain. He states that the pain started last night and has persisted until this morning. He describes the pain as in his chest and radiating into his back between his scapulae. The patient has a past medical history of alcohol abuse and cocaine abuse. He recently returned from vacation on a transatlantic flight. The patient has smoked 1 pack of cigarettes per day for the past 20 years. His temperature is 99.5°F (37.5°C), blood pressure is 167/118 mmHg, pulse is 120/min, and respirations are 22/min. Physical exam reveals tachycardia and clear air movement bilaterally on cardiopulmonary exam. Which of the following is also likely to be found in this patient?", "answer": "Asymmetric blood pressures in the upper extremities", "options": {"A": "Asymmetric blood pressures in the upper extremities", "B": "Coronary artery thrombus", "C": "Coronary artery vasospasm", "D": "Elevated lipase", "E": "Pulmonary artery thrombus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the physician because of right foot pain for 3 months. She has a burning sensation in the plantar area between the third and fourth metatarsals that radiates to the third and fourth digits. She had a right distal radius fracture that was treated with a splint and physical therapy three months ago. She is an account executive and wears high heels to work every day. Vital signs are within normal limits. Examination of the right lower extremity shows intact skin. The posterior tibial and dorsalis pedis pulses are palpable. When pressure is applied to the sole of the foot between the metatarsal heads the patient feels pain and there is an audible click. Tapping on the affected area causes pain that shoots into the third and fourth digits. Which of the following is the most likely diagnosis?", "answer": "Intermetatarsal neuroma", "options": {"A": "Third metatarsal stress fracture", "B": "Metatarsal osteochondrosis", "C": "Intermetatarsal neuroma", "D": "Ganglion cyst", "E": "Osteomyelitis\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought to the emergency department because of fever, cough, and ear pain over the past 2 days. He has had recurrent respiratory tract infections and several episodes of giardiasis and viral gastroenteritis since he was 6 months of age. Examination shows decreased breath sounds over both lung fields and bilateral purulent otorrhea. His palatine tonsils and adenoids are hypoplastic. Quantitative flow cytometry of his blood shows decreased levels of cells that express CD19, CD20, and CD21. Which of the following is the most likely cause of this patient's condition?", "answer": "Mutation in tyrosine kinase gene", "options": {"A": "Mutation in WAS gene", "B": "Mutation in tyrosine kinase gene", "C": "Microdeletion on the long arm of chromosome 22", "D": "Mutation in NADPH oxidase gene", "E": "Defect in beta-2 integrin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old woman, gravida 2, para 1, abortus 1, comes to the physician because of failure to conceive for 12 months. She is sexually active with her husband 2–3 times per week. Her first child was born at term after vaginal delivery 2 years ago. At that time, the postpartum course was complicated by hemorrhage from retained placental products, and the patient underwent dilation and curettage. Menses occur at regular 28-day intervals and previously lasted for 5 days with normal flow, but now last for 2 days with significantly reduced flow. She stopped taking oral contraceptives 1 year after the birth of her son. Her vital signs are within normal limits. Speculum examination shows a normal vagina and cervix. The uterus is normal in size, and no adnexal masses are palpated. Which of the following is the most appropriate next step in management?", "answer": "Hysteroscopy with potential adhesiolysis", "options": {"A": "Measurement of antisperm antibody concentration", "B": "Estrogen/progestin withdrawal test", "C": "Measurement of serum FSH and LH concentrations", "D": "Hysteroscopy with potential adhesiolysis", "E": "Dilation and curettage"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old man presents with a complaint of pain and swelling of his right leg for the past 2 days. He remembers hitting his leg against a table 3 days earlier. Since then, the pain and swelling of the leg have gradually increased. His past medical history is significant for atopy and pulmonary tuberculosis. The patient reports a 20-pack-year smoking history and currently smokes 2 packs of cigarettes per day. His pulse is 98/min, respiratory rate is 15/min, temperature is 38.4°C (101.2°F), and blood pressure is 100/60 mm Hg. On physical examination, his right leg is visibly swollen up to the groin with moderate erythema and 2+ pitting edema. The peripheral pulses are 2+ in the right leg and there is no discomfort. There is no increased resistance or pain in the right calf in response to forced dorsiflexion of the right foot. Which of the following is the best next step in the management of this patient?", "answer": "Ultrasound of the right leg", "options": {"A": "Reassurance and supportive treatment", "B": "Outpatient management with furosemide", "C": "D-dimer level", "D": "Ultrasound of the right leg", "E": "CT pulmonary angiography"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old Caucasian female presents with anemia, malaise, bloating, and diarrhea. Past genetic testing revealed that this patient carries the HLA-DQ2 allele. The physician suspects that the patient's presentation is dietary in cause. Which of the following findings would definitively confirm this diagnosis?", "answer": "Biopsy of the duodenum showing atrophy and blunting of villi", "options": {"A": "CT scan showing inflammation of the small bowel wall", "B": "Biopsy of the duodenum showing atrophy and blunting of villi", "C": "Biopsy of the colon showing epithelial cell apoptosis", "D": "Liver biopsy showing apoptosis of hepatocytes", "E": "Esophageal endoscopy showing lower esophageal metaplasia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 20-year-old woman presents to the emergency department with painful abdominal cramping. She states she has missed her menstrual period for 5 months, which her primary care physician attributes to her obesity. She has a history of a seizure disorder treated with valproic acid; however, she has not had a seizure in over 10 years and is no longer taking medications for her condition. She has also been diagnosed with pseudoseizures for which she takes fluoxetine and clonazepam. Her temperature is 98.0°F (36.7°C), blood pressure is 174/104 mmHg, pulse is 88/min, respirations are 19/min, and oxygen saturation is 98% on room air. Neurologic exam is unremarkable. Abdominal exam is notable for a morbidly obese and distended abdomen that is nontender. Laboratory studies are ordered as seen below.\n\nSerum:\nhCG: 100,000 mIU/mL\n\nUrine:\nColor: Amber\nhCG: Positive\nProtein: Positive\n\nDuring the patient's evaluation, she experiences 1 episode of tonic-clonic motions which persist for 5 minutes. Which of the following treatments is most appropriate for this patient?", "answer": "Magnesium", "options": {"A": "Lorazepam", "B": "Magnesium", "C": "Phenobarbital", "D": "Phenytoin", "E": "Propofol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old woman presents with severe abdominal pain and bloody diarrhea. Past medical history is significant for a myocardial infarction 6 months ago. The patient reports a 25-pack-year smoking history and consumes 80 ounces of alcohol per week. Physical examination shows a diffusely tender abdomen with the absence of bowel sounds. Plain abdominal radiography is negative for free air under the diaphragm. Laboratory findings show a serum amylase of 115 U/L, serum lipase 95 U/L. Her clinical condition deteriorates rapidly, and she dies. Which of the following would most likely be the finding on autopsy in this patient?", "answer": "Small bowel ischemia", "options": {"A": "Small bowel obstruction", "B": "Small bowel ischemia", "C": "Ulcerative colitis", "D": "Perforated appendicitis", "E": "Acute pancreatitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 43-year-old man comes to the physician because of left flank pain and nausea for 2 hours. The pain comes in waves and radiates to his groin. Over the past year, he has had intermittent pain in the bilateral flanks and recurrent joint pain in the toes, ankles, and fingers. He has not seen a physician in over 10 years. He takes no medications. He drinks 3–5 beers daily. His sister has rheumatoid arthritis. Vital signs are within normal limits. Physical examination shows marked tenderness bilaterally in the costovertebral areas. A photograph of the patient's left ear is shown. A CT scan of the abdomen shows multiple small kidney stones and a 7-mm left distal ureteral stone. A biopsy of the patient's external ear findings is most likely to show which of the following?", "answer": "Monosodium urate", "options": {"A": "Cholesterol", "B": "Ammonium magnesium phosphate", "C": "Monosodium urate", "D": "Palisading granulomas", "E": "Calcium oxalate"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 63-year-old female enrolls in a research study evaluating the use of iron studies to screen for disease in a population of post-menopausal women. Per study protocol, past medical history and other identifying information is unknown. The patient's iron studies return as follows:\n\nSerum iron: 200 µg/dL (normal 50–170 µg/dL)\nTIBC: 220 µg/dL (normal 250–370 µg/dL)\nTransferrin saturation: 91% (normal 15–50%)\nSerum ferritin: 180 µg/L (normal 15-150 µg/L)\n\nWhich of the following is the most likely cause of these findings?", "answer": "Excess iron absorption", "options": {"A": "Chronic inflammation", "B": "Excess iron absorption", "C": "Iron deficiency", "D": "Lead poisoning", "E": "Pregnancy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old woman with HIV comes to the physician because of a 3-day history of pain and watery discharge in her left eye. She also has blurry vision and noticed that she is more sensitive to light. Her right eye is asymptomatic. She had an episode of shingles 7 years ago. She was diagnosed with HIV 5 years ago. She admits that she takes her medication inconsistently. She wears contact lenses. Current medications include abacavir, lamivudine, efavirenz, and a nutritional supplement. Her temperature is 37°C (98.6°F), pulse is 89/min, and blood pressure is 110/70 mm Hg. Examination shows conjunctival injection of the left eye. Visual acuity is 20/20 in the right eye and 20/80 in the left eye. Extraocular movements are normal. Her CD4+ T-lymphocyte count is 90/mm3. A photograph of the left eye after fluorescein administration is shown. Which of the following is the most likely diagnosis?", "answer": "Herpes simplex keratitis", "options": {"A": "Neurotrophic keratopathy", "B": "Pseudomonas keratitis", "C": "Herpes zoster keratitis", "D": "Fusarium keratitis", "E": "Herpes simplex keratitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "While testing various strains of Streptococcus pneumoniae, a researcher discovers that a certain strain of this bacteria is unable to cause disease in mice when deposited in their lungs. What physiological test would most likely deviate from normal in this strain of bacteria as opposed to a typical strain?", "answer": "Quellung reaction", "options": {"A": "Bile solubility", "B": "Optochin sensitivity", "C": "Quellung reaction", "D": "Hemolytic reaction when grown on sheep blood agar", "E": "Motility"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old man comes to the physician because of progressive pain and swelling of his left knee for the past 2 days. He has been taking ibuprofen for the past 2 days without improvement. Four days ago, he scraped his left knee while playing baseball. He has a 2-month history of progressive pain and stiffness in his back. The pain starts after waking up and lasts for 20 minutes. He has type 2 diabetes mellitus. His older sister has rheumatoid arthritis. He is 170 cm (5 ft 7 in) tall and weighs 91 kg (201 lb); BMI is 31.5 kg/m2. Temperature is 39°C (102.2°F), pulse is 90/min, and blood pressure is 135/85 mm Hg. Examination shows an erythematous, tender, and swollen left knee; range of motion is limited. There are abrasions over the lateral aspect of the left knee. The remainder of the examination shows no abnormalities. Laboratory studies show a leukocyte count of 13,500/mm3 and an erythrocyte sedimentation rate of 70 mm/h. Which of the following is the most appropriate next step in management?", "answer": "Arthrocentesis of the left knee", "options": {"A": "Bone scan", "B": "MRI of the left knee", "C": "Blood cultures", "D": "Arthrocentesis of the left knee", "E": "Continued ibuprofen intake"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man with a past medical history notable for α-thalassemia now presents for urgent care with complaints of increased thirst and urinary frequency. Physical examination is grossly unremarkable, although there is a bronze discoloration of his skin. His vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. Laboratory analysis reveals fasting blood glucose of 192 mg/dL and subsequently, HbA1c of 8.7. Given the following options, what is the definitive treatment for the patient’s underlying disease?", "answer": "Recurrent phlebotomy", "options": {"A": "Metformin", "B": "Basal insulin", "C": "Basal and bolus insulin", "D": "Recurrent phlebotomy", "E": "Deferoxamine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 47-year-old woman complains of weight gain and irregular menses for the past 2 years. She has gained 13 kg (28,6 lb) and feels that most of the weight gain is in her abdomen and face. She has type 2 diabetes and hypertension for 1 year, and they are difficult to control with medications. Vital signs include a temperature of 36.9°C (98.4°F), blood pressure of 160/100 mm Hg, and pulse of 95/min. The patient late-night salivary cortisol is elevated. Morning plasma ACTH is high. Brain magnetic resonance imaging shows a 2 cm pituitary adenoma. Which of the following is the optimal therapy for this patient?", "answer": "Transsphenoidal pituitary adenoidectomy", "options": {"A": "Pituitary radiotherapy", "B": "Medical therapy", "C": "Unilateral adrenalectomy", "D": "Bilateral adrenalectomy", "E": "Transsphenoidal pituitary adenoidectomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 14-year-old boy is brought to the emergency department by his mom after she found him complaining of headaches, nausea, lightheadedness, and muscle pain. He has had type I diabetes for 3 years with very well managed blood sugars, and he is otherwise healthy. He recently returned from a boy scout skiing trip where he drank from a mountain stream, ate unusual foods, and lived in a lodge with a wood-fired fireplace and cooking stove. On physical exam he has a diffuse redness of his skin. Which of the following changes to this patient's pulmonary system would cause oxygen to exhibit similar transport dynamics as the most likely cause of this patient's symptoms?", "answer": "Interstitial fibrosis", "options": {"A": "Interstitial fibrosis", "B": "Interstitial thinning", "C": "Increasing capillary transit time", "D": "Increasing capillary length", "E": "Nitrous oxide administration"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A patient suffering from Graves' disease is given thiocyanate by his physician. Thiocyanate helps in the treatment of Graves' disease by:", "answer": "Inhibiting iodide follicular uptake", "options": {"A": "Inhibiting thyroid peroxidase", "B": "Inhibiting 5'-deiodinase", "C": "Inhibiting thyroid deiodinase", "D": "Inhibiting beta-adrenergic receptors", "E": "Inhibiting iodide follicular uptake"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-month-old male patient, with no significant past medical history, is brought into the emergency department for the second time in 5 days with tachypnea, expiratory wheezes and hypoxia. The patient presented to the emergency department initially due to rhinorrhea, fever and cough. He was treated with nasal suctioning and discharged home. The mother states that, over the past 5 days, the patient has started breathing faster with chest retractions. His vital signs are significant for a temperature of 100.7 F, respiratory rate of 45 and oxygen saturation of 90%. What is the most appropriate treatment for this patient?", "answer": "Nasal suctioning, oxygen therapy and IV fluids", "options": {"A": "Humidified oxygen, racemic epinephrine and intravenous (IV) dexamethasone", "B": "Albuterol, ipratropium and IV methylprednisolone", "C": "Intubation and IV cefuroxime", "D": "IV cefotaxime and IV vancomycin", "E": "Nasal suctioning, oxygen therapy and IV fluids"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 67-year-old man with type 2 diabetes mellitus comes to the emergency department because of lightheadedness over the past 2 hours. He reports that he has had similar episodes of lightheadedness and palpitations over the past 3 days. His only medication is metformin. His pulse is 110/min and irregularly irregular. An ECG shows a variable R-R interval and absence of P waves. The patient undergoes transesophageal echocardiography. During the procedure, the tip of the ultrasound probe is angled posteriorly within the esophagus. This view is most helpful for evaluating which of the following conditions?", "answer": "Aneurysm of the descending aorta", "options": {"A": "Thrombus in the left pulmonary artery", "B": "Myxoma in the left atrium", "C": "Aneurysm of the descending aorta", "D": "Thrombus in the left ventricular apex", "E": "Tumor in the right main bronchus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old female presents to her psychiatrist for ongoing management of major depressive disorder. She has previously tried cognitive behavioral therapy as well as selective serotonin reuptake inhibitors, but neither treatment has been very effective. She also states that she has been smoking two packs per day for the last three months and would like to stop smoking. Based on these concerns, her psychiatrist prescribes a medication that addresses both depression and smoking cessation. Which of the following if present, would be a contraindication for the drug that was most likely prescribed in this case?", "answer": "Patient is bulimic", "options": {"A": "Patient also takes monoamine oxidase inhibitors", "B": "Patient is elderly", "C": "Patient is bulimic", "D": "Patient works as a wine taster", "E": "Patient is pregnant"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-month-old boy is being treated for a rare kind of anemia and is currently being evaluated for a bone marrow transplant. The patient’s mother presents to an appointment with their pediatrician after having done some online research. She has learned that the majority of patients inherit this condition as an autosomal dominant mutation. As a result of the genetic mutation, there is impaired erythropoiesis, leading to macrocytic red blood cells without hypersegmented neutrophils. She also read that children who survive will eventually present with short stature and craniofacial abnormalities. Which of the following is true about this patient’s condition?", "answer": "Fetal hemoglobin level is elevated", "options": {"A": "Splenectomy is a treatment option", "B": "Occurs due to an inability to convert orotic acid to uridine monophosphate (UMP)", "C": "Fetal hemoglobin level is elevated", "D": "Occurs due to auto-antibodies against the parietal cells of the stomach", "E": "Occurs due to a defect in lymphoblasts and erythroid progenitor cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 44-year-old woman comes to the physician for the evaluation of a 1-month history of fatigue and difficulty swallowing. During this period, she has also had dry skin, thinning hair, and rounding of her face. She has type 1 diabetes mellitus and rheumatoid arthritis. Her father had a thyroidectomy for papillary thyroid cancer. The patient had smoked one pack of cigarettes daily for 20 years but quit 3 years ago. She drinks 2–3 glasses of wine daily. Her current medications include insulin, omeprazole, and daily ibuprofen. She appears well. Her temperature is 36.3°C (97.3°F), pulse is 62/min, and blood pressure is 102/76 mm Hg. Examination of the neck shows a painless, diffusely enlarged thyroid gland. Cardiopulmonary examination shows no abnormalities. Further evaluation is most likely to show which of the following?", "answer": "Positive thyroid peroxidase antibodies and thyroglobulin antibodies in serum", "options": {"A": "Large irregular nuclei, nuclear grooves, and Psammoma bodies on thyroid biopsy", "B": "Increased uptake on radioactive iodine scan in discrete 1-cm area", "C": "Diffusely increased uptake on a radioactive iodine scan", "D": "Positive immunohistochemical stain for calcitonin on thyroid biopsy", "E": "Positive thyroid peroxidase antibodies and thyroglobulin antibodies in serum"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 64-year-old man presents to his primary care provider after noticing the development of a blistering rash. The patient states that his symptoms began 1 week ago after he noticed a blister develop on the inside of his mouth that eventually ruptured. Over the past several days, he has noticed several more blisters on his torso. The patient denies a fever or any other symptoms. He has a history of high blood pressure, for which he takes hydrochlorothiazide. He is otherwise healthy and denies any recent changes to his medication. Today, the patient’s temperature is 99.0°F (37.2°C), blood pressure is 124/84 mmHg, pulse is 66/min, and respirations are 12/min. On exam, the patient’s mouth is notable for a previously ruptured blister on his left buccal mucosa. On his left flank and anterior abdomen are scattered 10-15-cm bullae that appear flaccid and filled with serous fluid. The lesions are erythematous but there is no surrounding erythema. On manual rubbing of the skin near the lesions, new blisters form within minutes. Which of the following is involved in the pathogenesis of this disease?", "answer": "IgG against transmembrane proteins between cells", "options": {"A": "Autoantibodies against hemidesmosomes", "B": "Exotoxin destroying keratinocyte attachments", "C": "IgA antibodies depositing in the dermal papillae", "D": "IgG against transmembrane proteins between cells", "E": "Viral infection of skin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is attempting to develop a blood test to diagnose sporadic Creutzfeld-Jacob disease (CJD). She has collected several tissue samples from adults who were diagnosed with CJD. After performing a comprehensive tissue analysis, she has identified two amino acid sequences on the affected proteins that are highly consistent across samples. She then creates antibodies that are highly specific to those amino acid sequences and is interested in using those antibodies to identify similar sequences in individuals suspected of having CJD. Which of the following tests would be most helpful in identifying these individuals?", "answer": "Western blot", "options": {"A": "Southern blot", "B": "Western blot", "C": "Northern blot", "D": "Southwestern blot", "E": "Polymerase chain reaction"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old woman presents to her primary care physician for her annual checkup. She lost her job 6 months ago and since then she has been feeling worthless because nobody wants to hire her. She also says that she is finding it difficult to concentrate, which is exacerbated by the fact that she has lost interest in activities that she used to love such as doing puzzles and working in the garden. She says that she is sleeping over 10 hours every day because she says it is difficult to find the energy to get up in the morning. She denies having any thoughts about suicide. Which of the following neurotransmitter profiles would most likely be seen in this patient?", "answer": "Decreased serotonin and norepinephrine", "options": {"A": "Decreased acetylcholine", "B": "Decreased gamma-aminobutyric acid", "C": "Decreased serotonin and norepinephrine", "D": "Increased dopamine", "E": "Increased norepinephrine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 46-year-old woman presents to a psychiatrist for evaluation. Three months prior, the patient moved to a new apartment building, and since then, she has become increasingly convinced that her doorman has been stealing her packages and going into her apartment while she is not home. She states that objects do not stay where she leaves them, and sometimes she expects mail but never receives it. She has filed numerous complaints with her leasing company. The building has 24-hour security footage, however, which has never shown any other person entering her apartment. On further questioning, the patient denies audiovisual hallucinations or changes in sleep, mood, energy levels, or eating. The family reports that her behavior and affect have not changed. The patient works as a pharmacist. She has no psychiatric history, although her father had a history major depressive disorder. Which of the following is the likely diagnosis?", "answer": "Delusional disorder", "options": {"A": "Adjustment disorder", "B": "Delusional disorder", "C": "Narcissistic personality disorder", "D": "Paranoid personality disorder", "E": "Schizotypal personality disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 71-year-old man with colorectal cancer comes to the physician for follow-up examination after undergoing a sigmoid colectomy. The physician recommends adjuvant chemotherapy with an agent that results in single-stranded DNA breaks. This chemotherapeutic agent most likely has an effect on which of the following enzymes?", "answer": "Topoisomerase I", "options": {"A": "Telomerase", "B": "Topoisomerase II", "C": "Helicase", "D": "DNA polymerase III", "E": "Topoisomerase I"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 10-year-old boy is brought to the emergency department 15 minutes after he had a seizure. His mother reports that he complained of sudden nausea and seeing “shiny lights,” after which the corner of his mouth and then his face began twitching. Next, he let out a loud scream, dropped to the floor unconscious, and began to jerk his arms and legs as well for about two minutes. On the way to the hospital, the boy regained consciousness, but was confused and could not speak clearly for about five minutes. He had a fever and sore throat one week ago which improved after treatment with acetaminophen. He appears lethargic and cannot recall what happened during the episode. His vital signs are within normal limits. He is oriented to time, place, and person. Deep tendon reflexes are 2+ bilaterally. There is muscular pain at attempts to elicit deep tendon reflexes. Physical and neurologic examinations show no other abnormalities. Which of the following is the most likely diagnosis?", "answer": "Focal to bilateral tonic-clonic seizure", "options": {"A": "Focal to bilateral tonic-clonic seizure", "B": "Convulsive syncope", "C": "Sydenham chorea", "D": "Generalized myoclonic seizure", "E": "Generalized tonic-clonic seizure\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old woman is in a high-speed motor vehicle accident and suffers multiple injuries to her extremities and abdomen. In the field, she was bleeding profusely bleeding and, upon arrival to the emergency department, she is lethargic and unable to speak. Her blood pressure on presentation is 70/40 mmHg. The trauma surgery team recommends emergency exploratory laparotomy. While the patient is in the trauma bay it is noted in the chart that the patient is a Jehovah's witness, and you are aware that her religion does not permit her to receive a blood transfusion. No advanced directives are available, but her ex-husband is contacted by phone and states that although they haven't spoken in a while, he thinks she would not want a transfusion. Which of the following is an appropriate next step?", "answer": "Provide transfusions as needed", "options": {"A": "Provide transfusions as needed", "B": "Ask ex-husband to bring identification to the trauma bay", "C": "Withhold transfusion based on ex-husband's request", "D": "Obtain an ethics consult", "E": "Obtain a court order for transfusion"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 14-year-old boy is brought to the office by his mother with the complaint of increasing bilateral nasal obstruction for the past 5 months. He also complains of continuous bilateral nasal discharge. He adds that he no longer has any sense of smell of foods. Past medical history is significant for growth retardation and chronic bronchitis at the age of 6 years. Anterior rhinoscopy reveals multiple semi-transparent, soft and mobile masses in the middle meatus. Which of the following is the most likely etiology of this patient’s condition?", "answer": "Nasal polyposis", "options": {"A": "Septal deviation", "B": "Nasal polyposis", "C": "Foreign body", "D": "Nonallergic rhinopathy", "E": "Juvenile nasopharyngeal angiofibroma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old man presents to a clinic with a complaint of intermittent flank pain bilaterally for 5 days. The pain is colicky in nature and radiates to the groin. The patient took an old prescription (hyoscyamine) and got some relief. He has nausea, but had not vomited until now. Although he has a history of renal stones, he denies any blood in the urine or stool and gives no history of fevers, changes in bowel habits, or abdominal distension. He does not have joint pain. On examination of the abdomen, the is no organomegaly and the bowel sounds are normal.\nThe blood test report reveals the following:\nSerum calcium 8.9 mg/dL\nSerum uric acid 8.9 mg/dL\nSerum creatinine 1.1 mg /dL\nThe urinalysis shows the following:\npH 6.0\nPus cells none\nRBCs 1–2/HPF\nEpithelial cells 1/HPF\nProtein negative\nKetones negative\nCrystals oxalate (plenty)\nAn abdominal ultrasound shows echogenic medullary pyramids with multiple dense echogenic foci in both kidneys, that cast posterior acoustic shadows. Which of the following best describes the pathogenesis of the disease process?", "answer": "Developmental anomaly characterized by cystic dilatation of the collecting tubules in the renal pyramids", "options": {"A": "Usually idiopathic in nature", "B": "Acquired condition secondary to dialysis", "C": "Developmental anomaly characterized by cystic dilatation of the collecting tubules in the renal pyramids", "D": "Neoplastic changes in the proximal tubular cells of the kidneys", "E": "Vascular anomalies and genetic mutations leading to maldevelopment of the kidneys"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 44-year-old man comes to the physician because of fatigue and increased straining during defecation for 3 months. During this time, he has lost 5 kg (12 lb) despite no change in appetite. He has a family history of colon cancer in his maternal uncle and maternal grandfather. His mother died of ovarian cancer at the age of 46. Physical examination shows conjunctival pallor. His hemoglobin concentration is 11.2 g/dL, hematocrit is 34%, and mean corpuscular volume is 76 μm3. Colonoscopy shows an exophytic mass in the ascending colon. Pathologic examination of the resected mass shows a poorly differentiated adenocarcinoma. Genetic analysis shows a mutation in the MSH2 gene. Which of the following is the most likely diagnosis?", "answer": "Lynch syndrome", "options": {"A": "Familial adenomatous polyposis", "B": "Turcot syndrome", "C": "Peutz-Jeghers syndrome", "D": "Gardner syndrome", "E": "Lynch syndrome"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old woman presents to the emergency department with a headache, fevers with chills, rigors, and generalized joint pain for the past week. She also complains of a progressive rash on her left arm. She says that a few days ago she noticed a small, slightly raised lesion resembling an insect bite mark, which had a burning sensation. The medical and surgical histories are unremarkable. She recalls walking in the woods 2 weeks prior to the onset of symptoms, but does not recall finding a tick on her body. On examination, the temperature is 40.2°C (104.4°F). A circular red rash measuring 10 cm x 5 cm in diameter is noted on the left arm, as shown in the accompanying image. The remainder of her physical examination is unremarkable. The tick causing her disease is also responsible for the transmission of which of the following pathogens?", "answer": "Babesia microti", "options": {"A": "Plasmodium vivax", "B": "Babesia microti", "C": "Ehrlichia", "D": "Rickettsia rickettsii", "E": "Rickettsia typhi"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old man comes to the physician because of recurrent episodes of right-sided jaw pain over the past 3 months. The patient describes the pain as dull. He says it worsens throughout the day and with chewing, and that it can also be felt in his right ear. He also reports hearing a cracking sound while eating. Over the past 2 months, he has had several episodes of severe headache that improves slightly with ibuprofen intake. Vital signs are within normal limits. Physical examination shows limited jaw opening. Palpation of the face shows facial muscle spasms. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Dysfunction of the temporomandibular joint", "options": {"A": "Dental abscess", "B": "Trigeminal nerve compression", "C": "Infection of the mandible", "D": "Dysfunction of the temporomandibular joint", "E": "Chronic inflammation of the sinuses\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old male is hospitalized for acute heart failure. The patient has a 20-year history of alcoholism and was diagnosed with diabetes mellitus type 2 (DM2) 5 years ago. Physical examination reveals ascites and engorged paraumbilical veins as well as 3+ pitting edema around both ankles. Liver function tests show elevations in gamma glutamyl transferase and aspartate transaminase (AST). Of the following medication, which most likely contributed to this patient's presentation?", "answer": "Pioglitazone", "options": {"A": "Glargine", "B": "Glipizide", "C": "Metformin", "D": "Pioglitazone", "E": "Pramlintide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old man with hypertension comes to the physician because of a 5-month history of a facial rash. He occasionally feels burning or stinging over the affected area. His only medication is lisinopril. Physical examination shows the findings in the photograph. Which of the following is the strongest predisposing factor for this patient's skin condition?", "answer": "Alcohol consumption", "options": {"A": "Cutibacterium colonization", "B": "Lisinopril therapy", "C": "Alcohol consumption", "D": "Filaggrin gene mutation", "E": "Complement component 1q deficiency"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old woman comes to the physician for the evaluation of sharp, stabbing pain in the lower back for 3 weeks. The pain radiates to the back of her right leg and is worse at night. She reports decreased sensation around her buttocks and inner thighs. During the last several days, she has had trouble urinating. Three years ago, she was diagnosed with breast cancer and was treated with lumpectomy and radiation. Her only medication is anastrozole. Her temperature is 37°C (98.6°F), pulse is 80/min, respirations are 12/min, and blood pressure is 130/70 mm Hg. Neurologic examination shows 4/5 strength in the left lower extremity and 2/5 strength in her right lower extremity. Knee and ankle reflexes are 1+ on the right. The resting anal sphincter tone is normal but the squeeze tone is reduced. Which of the following is the most likely diagnosis?", "answer": "Cauda equina syndrome", "options": {"A": "Conus medullaris syndrome", "B": "Cauda equina syndrome", "C": "Central cord syndrome", "D": "Brown-sequard syndrome", "E": "Anterior spinal cord syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 9-year-old boy presents to the emergency department with a 12 hour history of severe vomiting and increased sleepiness. He experienced high fever and muscle pain about 5 days prior to presentation, and his parents gave him an over the counter medication to control the fever at that time. On presentation, he is found to be afebrile though he is still somnolent and difficult to arouse. Physical exam reveals hepatomegaly and laboratory testing shows the following results:\n\nAlanine aminotransferase: 85 U/L\nAspartate aminotransferase: 78 U/L\n\nWhich of the following is the most likely cause of this patient's neurologic changes?", "answer": "Cerebral edema", "options": {"A": "Bacterial sepsis", "B": "Cerebral edema", "C": "Drug overdose", "D": "Subarachnoid hemorrhage", "E": "Viral meningitis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old boy presents to the emergency room with severe lower abdominal pain that awoke him from sleep about 3 hours ago. The pain is sharp and radiates to his left thigh. While in the emergency room, the patient experiences one episode of vomiting. His temperature is 99.3°F (37.4°C), blood pressure is 126/81 mmHg, pulse is 119/min, respirations are 14/min, and oxygen saturation is 99% on room air. Abdominal examination reveals no tenderness in all 4 quadrants. Scrotal examination reveals an elevated left testicle that is diffusely tender. Stroking of the patient's inner thigh on the left side does not result in elevation of the testicle. What is the next step in the management of this patient?", "answer": "Surgical exploration", "options": {"A": "CT scan of abdomen and pelvis", "B": "IV antibiotics", "C": "Observation and morphine", "D": "Surgical exploration", "E": "Testicular doppler ultrasound"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old man comes to the physician because of increasing pain in his right leg for 2 months. The pain persists throughout the day and is not relieved by rest. He tried taking acetaminophen, but it provided no relief from his symptoms. There is no family history of serious illness. He does not smoke. He occasionally drinks a beer. Vital signs are within normal limits. On examination, the right tibia is bowing anteriorly; range of motion is limited by pain. An x-ray of the right leg shows a deformed tibia with multiple lesions of increased and decreased density and a thickened cortical bone. Laboratory studies show markedly elevated serum alkaline phosphatase and normal calcium and phosphate levels. This patient is most likely to develop which of the following complications?", "answer": "Impaired hearing", "options": {"A": "Renal insufficiency", "B": "High-output cardiac failure", "C": "Osteosarcoma", "D": "Impaired hearing", "E": "Pancytopenia\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old woman presents to her primary care physician for bilateral nipple discharge. The patient states that she has observed a milky discharge coming from her nipples for the past month. On review of systems, the patient states that she has felt fatigued lately and has experienced decreased libido. She also endorses headaches that typically resolve by the middle of the day and a 5 pound weight gain this past month. The patient has a past medical history of obesity, schizophrenia, and constipation. Her temperature is 99.5°F (37.5°C), blood pressure is 145/95 mmHg, pulse is 60/min, respirations are 15/min, and oxygen saturation is 98% on room air. On physical exam, you note an obese, fatigued-appearing woman. Dermatologic exam reveals fine, thin hair over her body. Cardiopulmonary exam is within normal limits. Neurological exam reveals cranial nerves II-XII as grossly intact. The patient exhibits 1+ sluggish reflexes. Which of the following is the most likely diagnosis?", "answer": "Protein-secreting CNS mass", "options": {"A": "Viral infection of the thyroid gland", "B": "Autoimmune destruction of the thyroid gland", "C": "Protein-secreting CNS mass", "D": "Dopamine blockade in the tuberoinfundibular pathway", "E": "Normal pregnancy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 29-year-old woman presents to a medical office complaining of fatigue, nausea, and vomiting for 1 week. Recently, the smell of certain foods makes her nauseous. Her symptoms are more pronounced in the mornings. The emesis is clear-to-yellow without blood. She has had no recent travel out of the country. The medical history is significant for peptic ulcer, for which she takes pantoprazole. The blood pressure is 100/60 mm Hg, the pulse is 70/min, and the respiratory rate is 12/min. The physical examination reveals pale mucosa and conjunctiva, and bilateral breast tenderness. The LMP was 9 weeks ago. What is the most appropriate next step in the management of this patient?", "answer": "Beta-HCG levels and a transvaginal ultrasound", "options": {"A": "Abdominal CT with contrast", "B": "Beta-HCG levels and a transvaginal ultrasound", "C": "Beta-HCG levels and a transabdominal ultrasound", "D": "Beta-HCG levels and a pelvic CT", "E": "Abdominal x-ray"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old immigrant from Nigeria presents to the emergency department for sudden, severe pain and swelling in her lower extremity. She was at a rehabilitation hospital when her symptoms became apparent. The patient has a past medical history of obesity, diabetes, bipolar disorder, and tonic-clonic seizures. Her current medications include metformin, insulin, lisinopril, and valproic acid. The patient is a prominent IV drug and alcohol user who has presented to the ED many times for intoxication. On physical exam you note anasarca and asymmetric lower extremity swelling. Based on the results of a doppler ultrasound of her swollen lower extremity, heparin is started. The patient is then transferred to the general medicine floor for continued management. Laboratory studies are shown below.\n\nSerum:\nNa+: 137 mEq/L\nK+: 5.5 mEq/L\nCl-: 100 mEq/L\nHCO3-: 24 mEq/L\nUrea nitrogen: 22 mg/dL\nCa2+: 5.7 mg/dL\nCreatinine: 1.7 mg/dL\nGlucose: 70 mg/dL\n\nWhat is the most likely diagnosis?", "answer": "Nephrotic syndrome", "options": {"A": "Factor V Leiden", "B": "Antithrombin III deficiency", "C": "Prothrombin gene mutation", "D": "Liver failure", "E": "Nephrotic syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 41-year-old woman presents to the emergency room with chest pain. She has had progressive substernal chest pain accompanied by weakness and mild shortness of breath for the past 2 hours. Her past medical history is notable for poorly controlled systemic lupus erythematosus (SLE), Sjogren syndrome, and interstitial lung disease. She was hospitalized last year with pericarditis presumed to be from SLE. Her temperature is 98.6°F (37°C), blood pressure is 106/56 mmHg, pulse is 132/min, and respirations are 26/min. On exam, the skin overlying the internal jugular vein fills at 9 cm above the sternal angle and distant heart sounds are appreciated. There is no friction rub. She is given 1000cc of intravenous fluids with no appreciable change in her blood pressure. An electrocardiogram in this patient would most likely reveal which of the following findings?", "answer": "QRS complex height variation", "options": {"A": "Peaked T waves", "B": "ST elevations in leads II, III, and aVF", "C": "Polymorphic P waves", "D": "Wide QRS complexes with no P waves", "E": "QRS complex height variation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 14-year-old girl is brought to the emergency department because of a 3-day history of worsening confusion, high-grade fever, and a productive cough. She has had recurrent respiratory infections and bulky, foul-smelling, oily stools since infancy. She is at the 14th percentile for height and 8th percentile for weight. Despite appropriate care, the patient dies 2 days after admission. Autopsy of the lungs shows bronchial mucus plugging and bronchiectasis. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Deletion of phenylalanine codon on chromosome 7", "options": {"A": "Deletion of phenylalanine codon on chromosome 7", "B": "Deficiency in adenosine deaminase", "C": "Mutation of DNAI1 gene on chromosome 9", "D": "Deficiency in apolipoprotein B-48", "E": "Deficiency in alpha-1 antitrypsin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old woman presents to a physician for a new patient physical exam. Aside from occasional shin splints, she has a relatively unremarkable medical history. She takes oral contraceptive pills as scheduled and a multivitamin daily. She reports no known drug allergies. All of her age appropriate immunizations are up to date. Her periods have been regular, occurring once every 28 to 30 days with normal flow. She is sexually active with two partners, who use condoms routinely. She works as a cashier at the local grocery store. Her mother has diabetes and coronary artery disease, and her father passed away at age 45 after being diagnosed with colon cancer at age 40. Her grand-aunt underwent bilateral mastectomies after being diagnosed with breast cancer at age 60. Her physical exam is unremarkable. Which of the following is the best recommendation for this patient?", "answer": "Colonoscopy in 5 years", "options": {"A": "Colonoscopy in 5 years", "B": "Colonoscopy in 10 years", "C": "Pap smear with human papillomavirus (HPV) DNA testing now", "D": "Pap smear in 5 years", "E": "Mammogram now"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 35-year-old computer programmer presents to the psychiatrist at the request of his mother for his oddities. He explains that he wears an aluminum foil cap while he works because he does not want extraterrestial life to steal his thoughts. He spends his free time building a radio transmitter to contact distant planets. He denies any delusions or hallucinations. He claims that nothing is wrong with his eccentricities and is happy the way his life is. Which of the following personality disorders does this male most likely have?", "answer": "Schizotypal", "options": {"A": "Schizoid", "B": "Schizotypal", "C": "Paranoid", "D": "Narcissistic", "E": "Borderline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old homeless man is brought to the emergency department after he was found unconscious at the park. The patient's past medical history is unknown; however, he was admitted to the emergency department 2 times over the past year for severe pain treated with hydromorphone and IV fluids. His temperature is 100°F (37.8°C), blood pressure is 97/48 mmHg, pulse is 140/min, respirations are 18/min, and oxygen saturation is 99% on room air. The patient smells of alcohol and is covered in emesis. Basic laboratory values are ordered as seen below.\n\nHemoglobin: 6 g/dL\nHematocrit: 20%\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\nReticulocyte count: 0.4%\n\nWhich of the following is associated with the most likely diagnosis?", "answer": "Parvovirus B19 infection", "options": {"A": "Benign genetic carrier condition", "B": "Folate deficiency", "C": "Iron deficiency", "D": "Parvovirus B19 infection", "E": "Vitamin B12 deficiency"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 48-year-old patient with congestive heart failure is brought into the emergency room after an attempted suicide. He was found by his daughter whom he lives with while trying to suffocate himself. He had recently moved in with his daughter after his house went into foreclosure. The daughter lives in a small two-bedroom apartment that was recently baby proofed for her daughter. She cares for him and tries to help him with all of his medical appointments and taking his medications on time. He is noted to still consume moderate amounts of alcohol. She is concerned her father might try this again because his aunt died from suicide. Which of the circumstances is protective for this patient?", "answer": "Having a support system", "options": {"A": "Having a support system", "B": "Lack of access to sharp objects", "C": "Compliance with his medication", "D": "Lack of illicit drug use", "E": "Lack of immediate family history of suicide"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-year-old woman complains of severe vomiting for the past 2 hours. She recently had a chemotherapy session for breast cancer. She denies a history of any relevant gastrointestinal diseases, including GERD. The physical exam does not demonstrate any epigastric or abdominal tenderness. The last bowel movement was yesterday and was normal. What is the primary mechanism of the drug which would be prescribed to treat her chief complaint?", "answer": "5-HT3 blocker", "options": {"A": "D1 blocker", "B": "5-HT2 blocker", "C": "5-HT4 blocker", "D": "5-HT1 blocker", "E": "5-HT3 blocker"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 25-year-old male visits his primary care physician with complaints of hemoptysis and dysuria. Serum blood urea nitrogen and creatinine are elevated, blood pressure is 160/100 mm Hg, and urinalysis shows hematuria and RBC casts. A 24-hour urine excretion yields 1 gm/day protein. A kidney biopsy is obtained, and immunofluorescence shows linear IgG staining in the glomeruli. Which of the following antibodies is likely pathogenic for this patient’s disease?", "answer": "Anti-glomerular basement membrane antibody (Anti-GBM)", "options": {"A": "Anti-DNA antibody", "B": "Anti-neutrophil cytoplasmic antibody (C-ANCA)", "C": "Anti-neutrophil perinuclear antibody (P-ANCA)", "D": "Anti-glomerular basement membrane antibody (Anti-GBM)", "E": "Anti-phospholipid antibody"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old woman with multiple sclerosis comes to the physician because of a 4-day history of cramps in her left leg. Physical examination shows flexion of the left hip and increased tone in the thigh muscles. A local anesthetic block of which of the following nerves would most likely improve this patient's condition the most?", "answer": "Femoral nerve", "options": {"A": "Obturator nerve", "B": "Sciatic nerve", "C": "Inferior gluteal nerve", "D": "Femoral nerve", "E": "Superior gluteal nerve"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old male with a history of coronary artery disease, hypertension, hyperlipidemia, and type II diabetes presents to his primary care physician with increasing shortness of breath and ankle swelling over the past month. Which of the following findings is more likely to be seen in left-sided heart failure and less likely to be seen in right-sided heart failure?", "answer": "Basilar crackles on pulmonary auscultation", "options": {"A": "Increased ejection fraction on echocardiogram", "B": "Basilar crackles on pulmonary auscultation", "C": "Hepatojugular reflex", "D": "Lower extremity edema", "E": "Abdominal fullness"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old woman, gravida 1, para 1, presents to the obstetrics and gynecology clinic because of galactorrhea, fatigue, cold intolerance, hair loss, and unintentional weight gain for the past year. She had placenta accreta during her first pregnancy with an estimated blood loss of 2,000 mL. Her past medical history is otherwise unremarkable. Her vital signs are all within normal limits. Which of the following is the most likely cause of her symptoms?", "answer": "Sheehan’s syndrome", "options": {"A": "Addison’s disease", "B": "Cushing syndrome", "C": "Hashimoto thyroiditis", "D": "Pituitary adenoma", "E": "Sheehan’s syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 54-year-old man is referred to a tertiary care hospital with a history of 5 months of progressive difficulty in walking and left leg numbness. He first noticed mild gait unsteadiness and later developed gradual right leg weakness. His left leg developed progressive numbness and tingling. His blood pressure is 138/88 mm Hg, the heart rate is 72/min, and the temperature is 36.7°C (98.2°F). On physical examination, he is alert and oriented to person, place, and time. Cranial nerves are intact. Muscle strength is 5/5 in both upper extremities and left lower extremity, but 3/5 in the right leg with increased tone. The plantar reflex is extensor on the right. Pinprick sensation is decreased on the left side below the umbilicus. Vibration and joint position senses are decreased in the right foot and leg. All sensations are normal in the upper extremities. Finger-to-nose and heel-to-shin testing are normal. This patient’s lesion is most likely located in which of the following parts of the nervous system?", "answer": "Right hemi-spinal cord", "options": {"A": "Left frontal lobe", "B": "Left hemi-spinal cord", "C": "Right frontal lobe", "D": "Right hemi-spinal cord", "E": "Right pons"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 18-year-old woman presents to the emergency department with severe right lower quadrant discomfort and stomach pain for the past day. She has no significant past medical history. She states that she is sexually active and uses oral contraceptive pills for birth control. Her vital signs include: blood pressure 127/81 mm Hg, pulse 101/min, respiratory rate 19/min, and temperature 39.0°C (102.2°F). Abdominal examination is significant for focal tenderness and guarding in the right lower quadrant. Blood is drawn for lab tests which reveal the following:\nHb% 13 gm/dL\nTotal count (WBC) 15,400 /mm3\nDifferential count\nNeutrophils:  \nSegmented  70%\nBand Form 5%\nLymphocytes 20%\nMonocytes 5%\n What is the next best step in the management of this patient?", "answer": "Ultrasound of the appendix", "options": {"A": "Pelvic exam", "B": "Ultrasound of the pelvis", "C": "Ultrasound of the appendix", "D": "Upper gastrointestinal series", "E": "Upper gastrointestinal endoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A group of neurologists develop a new blood test for Alzheimer's. They are optimistic about the test, as they have found that for any given patient, the test repeatedly produces very similar results. However, they find that the new test results are not necessarily consistent with the gold standard of diagnosis. How would this new test most accurately be described?", "answer": "Reliable", "options": {"A": "Valid", "B": "Reliable", "C": "Biased", "D": "Valid and reliable", "E": "Neither valid nor reliable"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 6-year-old boy presents with fever, sore throat, hoarseness, and neck enlargement. The symptoms started 3 days ago and progressed gradually with an elevated temperature and swollen lymph nodes. His family immigrated recently from Honduras. He was born via spontaneous vaginal delivery at 39 weeks after an uneventful gestational period and he is now on a catch-up vaccination schedule. He lives with several family members, including his parents, in a small apartment. No one in the apartment smokes tobacco. On presentation, the patient’s blood pressure is 110/75 mm Hg, heart rate is 103/min, respiratory rate is 20/min, and temperature is 39.4°C (102.9°F). On physical examination, the child is acrocyanotic and somnolent. There is widespread cervical edema and enlargement of the cervical lymph nodes. The tonsils are covered with a gray, thick membrane which spreads beyond the tonsillar bed and reveals bleeding, erythematous mucosa with gentle scraping. The lungs are clear to auscultation. Which of the following is the target of the virulence factor produced by the pathologic organism infecting this child?", "answer": "Eukaryotic elongation factor-2 (eEF-2)", "options": {"A": "SNAP-25", "B": "ADP-ribosylation factor 6", "C": "Eukaryotic elongation factor-2 (eEF-2)", "D": "Desmoglein", "E": "RNA polymerase II"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old unconscious man is brought to the emergency department by a friend who witnessed him collapse. They were working in a greenhouse spraying the vegetables when the man started to complain of blurred vision and nausea. On the way to the hospital, the man lost consciousness and lost bladder continence. The patient’s vital signs are as follows: blood pressure 95/60 mm Hg; heart rate 59/min; respiratory rate 22/min; and temperature 36.0℃ (96.8℉). On examination, he is unconscious with a GCS score of 7. His pupils are contracted and react poorly to light. Lung auscultation reveals diffuse wheezing. Cardiac auscultation is significant for bradycardia. Abdominal auscultation reveals increased bowel sounds. A cardiac monitor shows bradycardia with grade 2 AV-block. Which of the following leads to the cardiac manifestations seen in this patient?", "answer": "Activation of M2-cholinergic receptors", "options": {"A": "Activation of M2-cholinergic receptors", "B": "Inhibition of β1-adrenergic receptors", "C": "Activation of β2-adrenergic receptors", "D": "Activation of M1-cholinergic receptors", "E": "Inhibition of M2-cholinergic receptors"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 10-year-old boy is brought to the physician by his mother because of a 2-day history of fever and productive cough. He has had similar episodes sporadically in the past with frequent episodes of thick, discolored nasal discharge. Physical examination shows diffuse crackles and rhonchi. An x-ray of the chest is shown. The most likely cause of recurrent infections in this patient is a dysfunction of which of the following cell types?", "answer": "Ciliated columnar cells", "options": {"A": "Alveolar macrophages", "B": "Ciliated columnar cells", "C": "Type I pneumocytes", "D": "Club cells", "E": "Type II pneumocytes"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A study is conducted in a hospital to estimate the prevalence of handwashing among healthcare workers. All of the hospital staff members are informed that the study is being conducted for 1 month, and the study method will be a passive observation of their daily routine at the hospital. A total of 89 medical staff members give their consent for the study, and they are followed for a month. This study could most likely suffer from which of the following biases?", "answer": "Hawthorne effect", "options": {"A": "Confounding bias", "B": "Observer-expectancy bias", "C": "Berksonian bias", "D": "Attrition bias", "E": "Hawthorne effect"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old man with angina pectoris comes to the physician because of a 6-month history of shortness of breath on exertion that improves with rest. He has hypertension and hyperlipidemia. Current medications include aspirin, metoprolol, and nitroglycerine. Echocardiography shows left ventricular septal and apical hypokinesis. Cardiac catheterization shows 96% occlusion of the left anterior descending artery. The patient undergoes angioplasty and placement of a stent. The patient's shortness of breath subsequently resolves and follow-up echocardiography one week later shows normal regional contractile function. Which of the following is the most accurate explanation for the changes in echocardiography?", "answer": "Hibernating myocardium", "options": {"A": "Unstable angina pectoris", "B": "Stress cardiomyopathy", "C": "Hibernating myocardium", "D": "Myocardial scarring", "E": "Cardiac remodeling"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman is brought to the emergency department 12 hours after ingesting 30 tablets of an unknown drug in a suicide attempt. The tablets belonged to her father, who has a chronic heart condition. She has had nausea and vomiting. She also reports blurring and yellowing of her vision. Her temperature is 36.7°C (98°F), pulse is 51/min, and blood pressure is 108/71 mm Hg. Abdominal examination shows diffuse tenderness with no guarding or rebound. Bowel sounds are normal. An ECG shows prolonged PR-intervals and flattened T-waves. Further evaluation is most likely to show which of the following electrolyte abnormalities?", "answer": "Increased serum K+", "options": {"A": "Increased serum Na+", "B": "Decreased serum K+", "C": "Increased serum Ca2+", "D": "Decreased serum Na+", "E": "Increased serum K+"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 78-year-old man presents with fatigue and exertional dyspnea. The patient says that symptoms onset gradually 4 weeks ago and have not improved. He denies any history of anemia or nutritional deficiency. Past medical history is significant for ST-elevation myocardial infarction 6 months ago, status post coronary artery bypass graft, complicated by recurrent hemodynamically unstable ventricular tachycardia. Current medications are rosuvastatin, aspirin, and amiodarone. His blood pressure is 100/70 mm Hg, the pulse is 71/min, the temperature is 36.5°C (97.7°F), and the respiratory rate is 16/min. On physical examination, patient appears lethargic and tired. Skin is dry and coarse, and there is generalized pitting edema present. A complete blood count (CBC) and a peripheral blood smear show evidence of normochromic, normocytic anemia. Additional laboratory tests reveal decreased serum level of iron, decreased TIBC (total iron-binding capacity) and increased serum level of ferritin. Which of the following is the most likely etiology of the anemia in this patient?", "answer": "Anemia of chronic disease", "options": {"A": "Iron deficiency anemia", "B": "Hemolytic anemia", "C": "Anemia of chronic disease", "D": "Pernicious anemia", "E": "Thalassemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old man presents to the emergency department after a fall. The patient was found lying down on the floor in his room in his retirement community. The patient has a past medical history of Alzheimer dementia and a prosthetic valve. His current medications include donepezil and warfarin. His temperature is 97.7°F (36.5°C), blood pressure is 85/50 mmHg, pulse is 160/min, respirations are 13/min, and oxygen saturation is 97% on room air. That patient is started on IV fluids and a type and screen is performed. Laboratory values are ordered as seen below.\n\nHemoglobin: 13 g/dL\nHematocrit: 39%\nLeukocyte count: 5,500 cells/mm^3 with normal differential\nPlatelet count: 225,000/mm^3\n\nINR: 2.5\nAST: 10 U/L\nALT: 12 U/L\n\nA chest radiograph and EKG are performed and are within normal limits. A full physical exam is within normal limits. The patient’s vitals are repeated. His temperature is 99.5°F (37.5°C), blood pressure is 110/70 mmHg, pulse is 90/min, respirations are 10/min, and oxygen saturation is 98% on room air. Which of the following is the best next step in management?", "answer": "CT scan", "options": {"A": "CT scan", "B": "Exploratory laparoscopy", "C": "Exploratory laparotomy", "D": "Fresh frozen plasma", "E": "Urgent blood transfusion"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 46-year-old woman presents to her primary care physician for her annual examination. At her prior exam one year earlier, she had a Pap smear which was within normal limits. Which of the following health screenings is recommended for this patient?", "answer": "Blood glucose and/or HbA1c screening", "options": {"A": "Blood glucose and/or HbA1c screening", "B": "Yearly Pap smear", "C": "Bone mineral density screening", "D": "Colorectal screening", "E": "Blood pressure at least once every 3 years"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 75-year-old woman comes to the physician because of a 3-month history of involuntary weight loss and a painless lump on her neck. Physical examination shows a firm, irregular swelling on the right side of the neck. Ultrasonography of the thyroid gland shows a 2-cm nodule with irregular margins and microcalcifications in the right thyroid lobe. A biopsy of the thyroid nodule is performed. Which of the following changes would be most consistent with anaplasia?", "answer": "Negative staining of tumor cells for thyroglobulin", "options": {"A": "Negative staining of tumor cells for thyroglobulin", "B": "Replacement of thyroid cells by normal squamous epithelium", "C": "Reduced number of functional thyroid cells", "D": "Disorganized proliferation of mature thyroid cells", "E": "Increased expression of thyroid transcription factor-1"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 13-year-old boy with a history of asthma and seasonal allergies is currently using albuterol to manage his asthma symptoms. Recently, his use of albuterol increased from 1–2 days/week to 4 times/week over the past several weeks, though he does not experience his symptoms daily. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. His physical examination shows clear, bilateral breath sounds and normal heart sounds. What change should be made to his current treatment regimen?", "answer": "Add fluticasone daily", "options": {"A": "Add salmeterol twice daily", "B": "Add montelukast 10 mg daily", "C": "Add fluticasone daily", "D": "Add formoterol + budesonide twice daily", "E": "Add tiotropium"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old woman comes to her physician because of increasing back pain for the past 10 months. The pain is worse in the morning when she wakes up and improves with activity. She used to practice yoga, but stopped 5 months ago as bending forward became increasingly difficult. She has also had bila