NBME 33 – Block 2

A 56-year-old woman undergoes pancreatectomy because of a mass in the head of the pancreas which has obstructed the common bile duct and produced jaundice. The mass is identified as a malignant neoplasm. The surrounding pancreas shows atrophy of the acinar tissue. Which of the following is the most likely cause of these findings?

A 5-year-old boy has a decreased hematocrit and hemoglobin concentration. Measurement of total iron-binding capacity shows that most of his transferrin is unsaturated. Which of the following describes the most likely condition of this patient’s iron stores?

A 64-year-old man comes to the physician because of an intensely itchy generalized rash. Physical examination shows generalized erythema and several indurated plaques and nodules. A photograph of the face is shown. There is axillary and inguinal lymphadenopathy. Skin biopsies show a dense cell infiltrate in the mid to upper dermis with invasion of the infiltrate into the epidermis. The contours of the nuclei of the cells in the infiltrate are markedly irregular and convoluted. Similar cells are found in the buffy coat of the peripheral blood. This dermal infiltrate is most likely composed of which of the following cells?

A 34-year-old Mexican American man comes to the physician for a health maintenance examination. He is active on an intramural basketball team, enjoys his job, and has three children. He eats spicy, salty food prepared by his wife at almost every meal. He says, “Sometimes I think maybe all that salt isn’t good for me, but my father ate food like this his entire life and he never had any health problems.” He is 173 cm (5 ft 8 in) tall and weighs 68 kg (149 lb); BMI is 23 kg/m2. His blood pressure is 159/96 mm Hg. Physical examination shows no other abnormalities. Similar blood pressure readings are obtained on two subsequent visits. Antihypertensive therapy is initiated. Which of the following is the most appropriate statement by the physician regarding this patient’s sodium intake?

A 65-year-old woman with a 2-year history of mitral stenosis comes to the physician because of cough productive of frothy fluid after mild exercise, shortness of breath with exertion, and wheezing. She says that she needs two pillows to help her breathe while sleeping. Her pulse is 115/min, respirations are 22/min, and blood pressure is 110/90 mm Hg. There is an accentuated S1 on auscultation of the chest. A chest x-ray shows alveolar infiltrates in the lower lung fields. Which of the following sets of findings is most likely in this patient’s lungs?

A 55-year-old man comes to the physician because of a 4-week history of dry mouth, muscle weakness, constipation, and episodes of dizziness while standing. He has smoked 2 packs of cigarettes daily for 30 years. Breath sounds are decreased over the right lower lobe. A chest x-ray shows a mass in the right lower lobe. A photomicrograph of a biopsy specimen from the mass is shown. Which of the following mechanisms is the most likely cause of the muscle weakness in this patient?

A 16-year-old girl is brought to the emergency department because of an 8-hour history of vomiting, a 1-day history of nausea and increasingly severe right flank pain, and a 2-day history of burning pain with urination and increased urinary frequency. She is sexually active with three male partners and uses no contraception. She appears ill and lethargic. Her temperature is 40.2°C (104.4°F), pulse is 140/min and regular, respirations are 16/min, and blood pressure is 100/50 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 100%. Physical examination shows marked right costovertebral angle tenderness. Cardiac examination shows no murmurs. The abdomen is soft and nontender. Pelvic examination shows no abnormalities. A urine pregnancy test result is positive. Laboratory studies are pending. Which of the following infectious agents is the most likely cause of the findings in this patient?

A 21-year-old woman is brought to the emergency department by police 1 hour after they found her standing in the middle of a highway, shouting. When the police confronted her, she said, “I can control them with my mind.” En route, they learned that she had been on a cross-country bus trip but had been asked to leave the bus; she explained that the bus driver said she was too loud and was flirting too much with the men and women on the bus. She then made sexual advances to the police officers and masturbated in the back seat of the patrol car. She says she has not slept during the past 9 days and adds, “Who has time to waste? I have places to see, people to meet, things to do.” She appears disheveled but healthy. Physical examination shows no abnormalities. On mental status examination, she is grandiose, expansive, and hypersexual. Her speech is rapid. She refuses to undergo cognitive testing. Which of the following is the most likely diagnosis?

An otherwise healthy 32-year-old woman comes to the physician because of the sudden onset of a painful lump in her vulva 3 days ago. She has had no difficulty with urination or pain with sexual intercourse. Physical examination shows a 2-cm, well-circumscribed, tender, freely mobile mass lateral to the vaginal introitus. The structure involved in the development of this mass most likely originates in which of the following embryologic structures?

A 62-year-old man is brought to the physician by his wife because of a 2-year history of mental status changes and agitation that have worsened during the past 4 months; he also has had a 10-kg (22-lb) weight loss during this period. He drinks approximately 1 pint of vodka daily. He appears disinterested, inattentive to his surroundings, and agitated. Ophthalmologic examination shows nystagmus, conjugate gaze palsy, and sluggishly reactive pupils. He walks slowly, with a broad-based gait. Laboratory studies show no abnormalities. Which of the following pathologic findings is most likely to be observed in this patient’s brain?

A 22-year-old woman is brought to the emergency department 3 hours after being sexually assaulted. The police report that she was alone in her apartment when an intruder broke in and raped her. When the physician meets the patient, the patient says she is so ashamed of what happened that she does not want to talk about it or be examined. Which of the following statements by the physician is likely to be most effective in establishing and maintaining rapport with this patient?

A 43-year-old man has weakness of the right lower two thirds of the face. Which of the following labeled sites on the photograph of the left hemisphere shown is most likely to be damaged?

A 27-year-old man comes to the physician because of a 3-week history of low-grade fever, night sweats, and nonproductive cough. He has a long history of Crohn disease treated with prednisone. His temperature is 37.9°C (100.2°F), pulse is 89/min, respirations are 16/min, and blood pressure is 132/68 mm Hg. A chest x-ray shows a patchy infiltrate and cavitary lesion in the right upper lobe. Acid-fast staining of a sputum sample is negative for bacilli. A photomicrograph of a silver-stained biopsy specimen of the lesion obtained via bronchoscopy is shown. Which of the following is the most likely causal organism?

A 26-year-old woman comes to the physician because of a 3-month history of palpitations; she has had a 5.4-kg (12-lb) weight loss during this period. She has had no neck pain. She does not smoke cigarettes or drink alcohol. She is 165 cm (5 ft 5 in) tall and now weighs 48 kg (105 lb); BMI is 18 kg/m2. Her temperature is 37°C (98.6°F), pulse is 110/min, respirations are 18/min, and blood pressure is 100/60 mm Hg. Physical examination shows a nontender, nonpalpable thyroid gland; there is no exophthalmos. Deep tendon reflexes are 3+ and brisk. Serum studies show:

Which of the following is the most likely cause of this patient’s condition?

A 29-year-old woman comes to the physician with her husband of 6 months because of pain with vaginal intercourse. She says that she can become aroused, but she is unable to have intercourse because of pain. Pelvic examination is limited because of involuntary spasm of the perineal muscles. Which of the following nerves is most likely involved in this patient’s disorder?

An 18-year-old man comes to the office because of a 2-year history of pale, scaly areas on the skin of his back and abdomen. He says these areas are more noticeable during the summer months. Physical examination shows scattered 1- to 2-cm patches of hypopigmentation and scarring over the skin of the trunk. Microscopic examination of a scraping of one of these patches mixed with 20% KOH shows fungal hyphae and yeast. The activity of which of the following cutaneous enzymes is most likely inhibited by the fungus?

A 26-year-old woman (individual II-1 in the pedigree shown) and her 25-year-old husband (individual II-2) come to the office for genetic counseling prior to conception. The husband has a family history of Huntington disease, which has been clinically diagnosed in his mother (individual I-2) and a maternal aunt (individual I-4). Which of the following best represents the probability that this couple’s child (individual III-1) will develop Huntington disease later in life?

A 43-year-old man comes to the physician for a routine health maintenance examination. His father died of a myocardial infarction at the age of 49 years, and his brother had a myocardial infarction at the age of 41 years. Physical examination shows no abnormalities. Serum lipid and high sensitivity C-reactive protein concentrations are obtained. Based on the results, a drug is prescribed to be taken once daily. One year later, the same serum analysis is performed. The results are shown in the table:

Which of the following drugs most likely caused the changes in this patient’s serum findings?

A 58-year-old man is admitted to the intensive care unit for respiratory failure. He is receiving mechanical ventilation. He also had urosepsis that was complicated by aspiration pneumonia. For the past 3 days, the care team has repeatedly attempted to wean the patient from an Fio2 of 1.0, but each time, his Po2 decreases into the 50 to 60 mm Hg range. This patient is at increased risk for damage to type II pneumocytes from which of the following?

A 20-year-old man comes to the physician for a follow-up examination after blood pressure measurements were 175/105 mm Hg and 185/110 mm Hg 1 and 3 weeks ago, respectively. He is not obese, eats a healthy diet, and does not use illicit drugs. He has no family history of hypertension. His blood pressure now is 180/110 mm Hg. Physical examination shows no other abnormalities. Routine laboratory studies, including serum electrolyte concentrations, show no abnormalities. Antihypertensive treatment is started, but his blood pressure remains elevated at his next visit 3 weeks later, and his plasma renin activity is markedly increased in the left renal vein compared with the right renal vein. Renal angiography shows a pattern of “peaks and valleys” in the left renal artery. Which of the following is the most likely diagnosis?

A 28-year-old man comes to the physician because of weakness for 2 months; he has had a 4.5-kg (10-lb) weight loss during this period. There is no family history of cancer. Laboratory studies show a hemoglobin concentration of 8 g/dL. A chest x-ray shows multiple pulmonary nodules of varying sizes throughout both lung fields. A diagnosis of metastatic cancer is made. Which of the following organs is the most likely primary source of the cancer?

A 1-year-old girl is brought to the physician by her mother because of a 2-day history of poor eating and vomiting after she was diagnosed with an upper respiratory tract infection. She appears lethargic. Physical examination shows mild hepatomegaly. Serum studies show hypoglycemia and absence of ketones. Urine studies show increased concentrations of acylcarnitines and dicarboxylic acids. A defect in which of the following processes best explains the findings in this patient?

A 48-year-old woman comes to the physician for a follow-up examination. She received a diagnosis of type 2 diabetes mellitus at her last examination 1 week ago. Her mother had complications related to this disease. The patient is a college graduate. She often uses the Internet to do research for her job. Today she is given a pamphlet explaining the importance of diet, exercise, and weight management in controlling her disease. Which of the following initial statements by the physician is most likely to ensure that this patient will read and keep the pamphlet for future referral?

A 14-year-old girl is brought to the office by her mother for a well-child examination. She has no history of major medical illness and takes no medications. She has never had a menstrual period. She has no history of physical, sexual, or emotional abuse. After the mother leaves the room, the patient says she has not had depressed mood or anxiety. She does not smoke, drink alcoholic beverages, or use illicit drugs. She has never been sexually active. She has a good relationship with her parents and siblings. She is a freshman in high school and receives grades of As and Bs. She plays soccer three days weekly. She is at the 75th percentile for height, weight, and BMI. Vital signs are within normal limits. Sexual maturity rating is 4 for breast development and 3 for pubic hair development. The remainder of the examination shows no abnormalities. Which of the following is the most likely explanation for this patient’s lack of menstrual period?

A 14-year-old boy is brought to the office by his mother for an examination prior to participating on his school’s long-distance running team. During the interview, the patient says that he has been using increasing amounts of erythropoietin to try to increase his oxygen capacity in preparation for the season. Which of the following physical parameters is most likely to be adversely affected in this patient as a result of the use of this drug?

A previously healthy 79-year-old woman has had thoracolumbar back pain since the car she was riding in hit a pothole 4 days ago. A lateral x-ray of her spine is shown. Which of the following is the most likely underlying cause of the abnormality shown?

A 10-year-old girl with a lifelong history of intermittent dyspnea is brought to the physician for a follow-up examination. During an episode of dyspnea, she turns blue. The episode resolves after she squats. A systolic murmur was heard at birth. Today, a grade 4/6 systolic murmur is heard at the pulmonic area, radiating widely to the back and left side. Cardiac catheterization shows:

This patient’s condition is most likely caused by which of the following embryologic defects?

A previously healthy 35-year-old woman comes to the physician because of a 2-month history of abdominal cramping and intermittent bloody diarrhea. She takes no medications. Physical examination shows no abnormalities. Colonoscopy confirms the diagnosis of ulcerative colitis. Treatment is initiated with a drug containing an azo (N=N) bond to an inert compound, that prevents absorption in the small intestine for maximal direct effect in the colon. This drug is most likely which of the following?

A 51-year-old woman comes to the physician because of a 3-month history of urinary frequency and pain with urination. The patient says, “The pain started a couple of days after I returned from a trip to the Caribbean.” She has smoked 2 packs of cigarettes daily for 30 years. She used an oral contraceptive for 30 years. Menopause occurred 2 years ago. Her mother died of breast cancer at the age of 55 years. Physical examination shows no abnormalities. Urinalysis shows a pH of 6.5, specific gravity of 1.013, and 1+ blood. Cystoscopy shows mucosal irregularity with erythema in the dome of the bladder. A photomicrograph of a biopsy specimen of the lesion is shown. Which of the following is the strongest predisposing risk factor for this condition?

A 54-year-old man comes to the office for a follow-up examination. He has an 8-year history of HIV infection well controlled with antiretroviral therapy. Vital signs are within normal limits. Physical examination shows facial and peripheral wasting, central obesity, and enlargement of the dorsocervical fat pad and breasts. A drug to treat HIV infection from which of the following classes is the most likely cause of these findings?

A 44-year-old man comes to the physician for a health maintenance examination. He has drunk twelve 12-oz beers nightly for several years. He tells the physician that he is concerned he may have a drinking problem, but he has not mentioned the concern to anyone else. He says, “Most of my friends drink the same amount and I’m afraid they’ll think I’m overreacting if I talk to them about it.” Which of the following best describes this patient’s stage of behavioral change?

A 16-year-old girl is brought to the physician by her mother because she has had bowed legs since the age of 12 years. She is a member of the track team at school and feels this deformity is affecting her performance. Examination of the patient’s gait shows bilateral genu varum. Excess stress is most likely being placed on which of the following lateral structures in this patient?

A 50-year-old woman develops decreased urine output and an increasing serum creatinine concentration 6 weeks after a kidney transplantation. A diagnosis of acute rejection is suspected. Which of the following findings on biopsy of the transplanted kidney is most likely to confirm the diagnosis?

A 25-year-old man is scheduled to undergo an operation for a thymoma. He says that he had muscle weakness before the operation. He regularly eats at sushi bars. Sevoflurane and pancuronium are used perioperatively. Postoperatively, the patient has profound residual neuromuscular block. If electrophysiologic evaluation of skeletal muscle were done at this time, results would show:

Which of the following is the most likely cause of these findings?

An investigator conducts a retrospective analysis of medullary carcinomas of the thyroid gland. Microscopic features of tumors arising in patients with a positive family history are compared with features of tumors that occurred sporadically. The familial tumors are more likely to exhibit which of the following?

A 74-year-old woman comes to the emergency department because of a 3-day history of abdominal pain, vomiting, and constipation. Physical examination shows tenderness to deep palpation of the right upper abdominal quadrant. An abdominal x-ray shows dilation of the small intestine in the left upper quadrant. Abdominal ultrasonography shows multiple dilated small-bowel loops and air in the gallbladder. The most likely cause of these findings is a gallstone lodged in which of the following locations?

A 29-year-old man with bronchiectasis comes to the physician for a routine follow-up examination. Physical examination shows the tissue of the proximal nail fold to have a spongy resilience, and the nail plate to be at a 180° angle with the long axis of the finger. These findings best describe which of the following?

A study is conducted to assess the effects of in vitro fertilization (IVF) on preterm delivery. Women who conceive using IVF are compared with a control group of women who conceive naturally. The women are matched by maternal age and parity, and only singleton gestations are included in the study. Gestational age at delivery is recorded for both groups. Results show a statistically significant association between the use of IVF and preterm delivery. Which of the following best describes this study design?

A 35-year-old woman is scheduled to undergo an exploratory operation for suspected lung cancer after a chest x-ray shows a suspicious mass. A CT scan–style drawing of a cross section of the chest is shown; the X indicates the area of the mass. Which of the following labeled areas in the diagram of the lungs is the most likely location of this mass in the patient?

A 35-year-old man with a 1-year history of fluctuating, crampy abdominal pain in the right lower quadrant comes to the physician because of a 6-month history of decreased appetite and diarrhea tinged with blood and mucus. He has had a 6.8-kg (15-lb) weight loss during the past 6 months. Vital signs are within normal limits. Test of the stool for occult blood is positive. Which of the following is the most likely diagnosis?

A 19-year-old woman is brought to the emergency department 1 hour after the sudden onset of palpitations, sweating, tremor, a choking sensation, chest pain, nausea, dizziness, and numbness of her hands. Her temperature is 37°C (98.6°F), pulse is 100/min, respirations are 18/min, and blood pressure is 110/70 mm Hg. Neurologic and mental status examinations show no abnormalities. Laboratory studies show:

Her symptoms resolve within 1 hour without treatment. She continues to have similar episodes during the next 5 years and worries about having them. Which of the following is the most likely diagnosis?

A 1500-g (3-lb 5-oz) male newborn is delivered by cesarean section at 28 weeks’ gestation after his mother sustained accidental trauma to the abdomen that resulted in near total loss of amniotic fluid. Apgar scores are 1 and 3 at 1 and 5 minutes, respectively. Physical examination shows cyanosis. Interventional intubation and mechanical ventilation are started, but the newborn dies 15 minutes after birth. Which of the following findings in the lungs and chest are most likely on autopsy?

A 19-year-old man is admitted to the hospital because of deep venous thrombosis of the left thigh. He had a similar episode 4 years ago that was treated with a 6-month course of apixaban. His father and his older brother have a history of deep venous thrombosis. Further analysis shows hypercoagulability. This patient’s condition is most likely caused by factor V resistance to cleavage by which of the following?

A 16-year-old boy with asthma is brought to the clinic for a routine examination. He feels well. Medications are twice-daily inhaled budesonide, daily oral montelukast, and as-needed inhaled albuterol. He does not smoke cigarettes, drink alcohol, or use illicit drugs. He appears well. He is at the 90th percentile for height, weight, and BMI. Temperature is 37.0°C (98.6°F), pulse is 70/min, respirations are 16/min, and blood pressure is 125/75 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 100%. End-expiratory wheezes are heard bilaterally. It is most appropriate to obtain specific additional history regarding which of the following at this time?

A 10-year-old girl is brought to the physician by her mother because of a 6-month history of acne, increased facial and body hair, and a deepening voice. Her blood pressure is 132/88 mm Hg. Physical examination shows hirsutism and clitorimegaly. Serum studies show a decreased potassium concentration and increased 11-deoxycortisol concentration. Further studies show a deficiency in the activity of 11β-hydroxylase. The most likely cause of the hypertension in this patient is an increased serum concentration of which of the following?

A 58-year-old man is brought to the emergency department 30 minutes after he was involved in a motor vehicle collision. Physical examination shows inability to raise the right upper extremity. A CT scan shows a nondisplaced fracture of the right clavicle, in addition to a 4.5-cm multiloculated mass in the left kidney and a 4.5-cm aneurysmal dilation of the abdominal aorta. There is also irregular lymphadenopathy of the left para-aortic (lumbar) lymph nodes. Laboratory studies show a serum calcium concentration of 13.7 mg/dL. Which of the following is the most likely cause of the serum calcium findings in this patient?

A 5-month-old boy is brought to the physician because of a 2-day history of fever, wet cough, and rash. His temperature is 39°C (102.2°F). Physical examination shows lymphadenopathy, pustules over the upper and lower extremities, and hepatosplenomegaly. Flow cytometric analysis of whole blood shows the absence of reduction of dihydrorhodamine by the patient’s cells. This patient’s condition is most likely caused by a defect in the production of which of the following by phagocytes?

A 72-year-old woman comes to the physician for a follow-up examination. She has a history of coronary artery disease, hypercholesterolemia, and mild hypertension. She had smoked 1 pack of cigarettes daily for 40 years before she quit 2 years ago. Her pulse is 68/min and regular, respirations are 16/min, and blood pressure is 180/72 mm Hg. Physical examination shows diminished ankle and pedal pulses bilaterally. There is no peripheral edema. Cardiac examination shows a grade 2/6 coarse crescendo-decrescendo murmur that is best heard at the base. There is a soft S4 gallop. Bruits are also heard over the right periumbilical area and left femoral artery. Serum studies show:

The physician considers adding lisinopril to the patient’s medication regimen. Which of the following sets of physiologic changes is most likely in this patient if this therapy is initiated?

A 55-year-old woman comes to the physician for a routine health maintenance examination. Pelvic examination shows an enlarged right ovary. After surgical excision of the ovary, the specimen shows a primary malignant neoplasm. This patient is at increased risk for metastasis in which of the following lymph nodes that drains the ovary?

A previously healthy 65-year-old man comes to the physician because of a 4-week history of weakness and abdominal pain. He worked in a variety of manufacturing plants before retiring 2 years ago. He appears well. Abdominal examination shows a mass in the right upper quadrant. A CT scan of the abdomen shows a 4-cm tumor. He is diagnosed with liver cancer. Exposure to which of the following is the most likely cause of his liver cancer?