Context: 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?

Question: Which of the following is the next best step for this patient?

Answer: Physical therapy


Context:
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:
Urea nitrogen 16 mg/dl
Glucose 103 mg/dL
Creatinine 0.7 mg/dL
Troponin I 0.230 ng/mL (N < 0.1 ng/mL)
An ECG shows diffuse ST elevations in all leads. The patient is at increased risk for which of the following conditions?"

Question: The patient is at increased risk for which of the following conditions?"

Answer: Cardiac tamponade


Context: 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?

Question: Which of the following is the most likely explanation for this patient's skin findings?

Answer: Cutaneous mast cell activation


Context: 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?

Question: What is the next best step in the management of this patient?

Answer: Exercise therapy with NSAIDs/acetaminophen


Context: 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?

Question: Which of the following is the most likely cause of this patient's symptoms?

Answer: Calcification of the aortic valve


Context: 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?

Question: You begin him on a first-line medication for this illness, which works by which mechanism of action?

Answer: Enhances release of norepinephrine vesicles


Context:
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:
Finger-stick glucose  530 mg/dL
    Arterial blood gas analysis
pH 7.1
pO2 94 mm Hg
pCO2 32 mm Hg
HCO3 17 mEq/L
    Serum
Sodium 136 mEq/L
Potassium 3.2 mEq/L
Chloride 136 mEq/L
    Blood urea nitrogen  20 mg/dL
Serum creatinine 1.2 mg/dL
    Urine examination
Glucose positive
Ketones positive
Leucocytes negative
Nitrite negative
RBC negative
Casts negative
Which of the following abnormalities accounts for her sweet smelling breath?

Question:
The laboratory findings include:
Finger-stick glucose  530 mg/dL
    Arterial blood gas analysis
pH 7.1
pO2 94 mm Hg
pCO2 32 mm Hg
HCO3 17 mEq/L
    Serum
Sodium 136 mEq/L
Potassium 3.2 mEq/L
Chloride 136 mEq/L
    Blood urea nitrogen  20 mg/dL
Serum creatinine 1.2 mg/dL
    Urine examination
Glucose positive
Ketones positive
Leucocytes negative
Nitrite negative
RBC negative
Casts negative
Which of the following abnormalities accounts for her sweet smelling breath?

Answer: Excessive mobilization of fatty acids


Context: 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?

Question: Which of the following is the most likely diagnosis in this patient?

Answer: Macular degeneration


Context: 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?

Question: Which of the following is the most likely cause of her symptoms?

Answer: Sjögren's syndrome


Context: 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?

Question: Which of the following physical exam findings was most likely missed by both the medical student and primary care physician?

Answer: Webbed neck


Context:
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.
Laboratory test
Complete blood count
Hemoglobin 13 g/dL
WBC 15,500/mm3
Platelets 145,000/mm3
Basic metabolic panel
Serum Na+   137 mEq/L
Serum K+ 3.6 mEq/L
Serum Cl-   95 mEq/L
Serum HCO3- 25 mEq/L
BUN   10 mg/dL
Serum creatinine        0.8 mg/dL
Liver function test
Total bilirubin   1.3 mg/dL
AST   52 U/L
ALT 60 U/L
Ultrasonography of the abdomen shows normal findings. What is the best next step in management of this patient?

Question: What is the best next step in management of this patient?

Answer: Cholescintigraphy


Context:
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:
Hemoglobin 10.1 g/dL
Leukocyte count 63,000/mm3
Platelet count 27,000/mm3
A bone marrow aspirate predominantly shows immature cells that stain positive for CD10, CD19, and TdT. Which of the following is the most likely diagnosis?"

Question: Which of the following is the most likely diagnosis?"

Answer: Acute lymphoblastic leukemia


Context: 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?

Question: Which of the following is the most likely causal organism of this patient's symptoms?

Answer: Staphylococcus saprophyticus


Context:
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:

Orotic acid: 9.2 mmol/mol creatinine (normal: 1.4-5.3 mmol/mol creatinine)
Ammonia: 135 µmol/L (normal: < 50 µmol/L)
Citrulline: 2 µmol/L (normal: 10-45 µmol/L)

Which of the following treatments would most likely be beneficial to this patient?

Question:
Laboratories are obtained with the following results:

Orotic acid: 9.2 mmol/mol creatinine (normal: 1.4-5.3 mmol/mol creatinine)
Ammonia: 135 µmol/L (normal: < 50 µmol/L)
Citrulline: 2 µmol/L (normal: 10-45 µmol/L)

Which of the following treatments would most likely be beneficial to this patient?

Answer: Benzoate administration


Context: 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?

Question: Repeats of which of the following trinucleotides are most likely responsible for this patient’s disorder?

Answer: CAG


Context: 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?

Question: The structure indicated by the arrow is most likely comprised of which of the following types of cells?

Answer: Macrophages


Context: 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?

Question: Which of the following phenomena explains why she has not contracted any vaccine-preventable diseases such as measles, diphtheria, or pertussis?

Answer: Herd immunity


Context: 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?

Question: Where is the most likely site that this process occurs?

Answer: P site


Context: 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?

Question: Which of the following is the most likely mechanism underlying this patient's skin findings?

Answer: Extravasation of lipoproteins


Context: 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?

Question: Further evaluation is most likely to show which of the following?

Answer: Asymmetric septal hypertrophy


Context: 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?

Question: What changes would be expected to be seen at the level of glomerular filtration?

Answer: Increase in Bowman's space hydrostatic pressure


Context: 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?

Question: Which of the following is the most likely cause of this patient's presentation?

Answer: Cocaine intoxication


Context: 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?

Question: Repeats of which of the following trinucleotides are most likely responsible for this patient’s disorder?

Answer: CAG


Context: 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?

Question: Which of the following is the most likely diagnosis?

Answer: Major depressive disorder


Context: 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?

Question: Which of the following is the most likely diagnosis?

Answer: De Quervain tenosynovitis


Context: 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?

Question: Which of the following is the most appropriate pharmacotherapy for this patient's condition at this time?

Answer: Oral contraceptive


Context:
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 :
pH 7.30
PCO2 38 mm Hg
PO2 70 mm Hg
HCO3- 18 mEq/L
COHb 2% (N < 3)
In addition to oxygen supplementation with a non-rebreather mask, which of the following is the most appropriate next step in management?"

Question:
Arterial blood gas analysis on room air shows :
pH 7.30
PCO2 38 mm Hg
PO2 70 mm Hg
HCO3- 18 mEq/L
COHb 2% (N < 3)
In 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


Context: 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?

Question: Which of the following is the most appropriate action by the doctor?

Answer: Warn the person at risk and inform law enforcement


Context: 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?

Question: Which of the following is the most immediate physiologic effect of the medication in question?

Answer: Decreased sodium reabsorption in the collecting duct


Context: 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?

Question: Exposure to which of the following was the likely cause of this patient's condition?

Answer: Undercooked pork


Context: 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?

Question: Damage to which of the following nerves is responsible for the impaired cough reflex in this patient?

Answer: Internal laryngeal nerve


Context: 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?

Question: Which of the following laboratory findings is most reliably positive for the primary cause of this illness?

Answer: Tartrate-resistant acid phosphatase (TRAP)


Context: 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?

Question: Which of the following is the most likely cause of this patient's findings?

Answer: Mucosal tear at the gastroesophageal junction


Context: 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?

Question: Which of the following serum assays is the most appropriate next step in the diagnosis of this patient's condition?

Answer: Human chorionic gonadotropin


Context: 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?

Question: Which of the following best explains these findings?

Answer: Whipple’s disease


Context:
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:
pH 7.33
PCO2 53 mm Hg
PO2 68 mm Hg
An 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?"

Question: Which of the following additional findings is most likely in this patient?"

Answer: Decreased urinary bicarbonate excretion


Context: 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?

Question: Which of the following is this patient's strongest predisposing factor for developing this condition?

Answer: Early onset of sexual activity


Context: 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?

Question: Which of the following is the most appropriate next step in management?

Answer: Proctocolectomy with ileoanal anastomosis


Context: 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?

Question: One codon for leucine is CUU, which of the following can be another codon coding for leucine?

Answer: CUA


Context: 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?

Question: 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


Context: 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?

Question: What is the next best step in diagnosis?

Answer: Ventilation-perfusion scan


Context: 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?

Question: Which of the following is the most appropriate initial pharmacotherapy?

Answer: Trimethoprim/sulfamethoxazole


Context:
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:

Alkaline phosphatase: 110 U/L
Aspartate aminotransferase (AST, GOT): 100 U/L
Alanine aminotransferase (ALT, GPT): 120 U/L
Bilirubin total: 2.2 mg/dL

Liver biopsy shows mixed dense interstitial lymphocytic infiltrates in the portal triad. What is the mechanism of this reaction?

Question: What is the mechanism of this reaction?

Answer: CD8+ T lymphocytes reacting against donor MHCs


Context: 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?

Question: What is the most likely cause of the patient's presentation?

Answer: A gastrin-secreting tumor of the pancreas


Context: 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?

Question: Which of the following is the most appropriate pharmacotherapy for this patient's current symptoms?

Answer: Prednisone


Context: 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?

Question: Therefore, compared to a normal artery with no stenosis, by what factor has the flow of blood been decreased?

Answer: 16


Context: 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?

Question: 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.


Context: 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?

Question: Which of the following would you expect to find in this patient?

Answer: Mucosal arteriovenous malformations


Context: 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?

Question: Which of the following tests is most likely to reveal the cause of the patient’s symptoms?

Answer: Echocardiography


Context: 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?

Question: Which of the following maternal risk factors is most likely associated with early pregnancy loss?

Answer: Age


Context: 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?

Question: The expected beneficial effect of the prescribed drug is most likely due to which of the following effects?

Answer: Direct inhibition of thrombin


Context: 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?

Question: Of the following cell types, which one would have mediated the reaction?

Answer: T-cells


Context: 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?

Question: Administration of which of the following agents is the most appropriate next step in management?

Answer: HMG-CoA reductase inhibitor


Context: 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?

Question: 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


Context: 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?

Question: This patient most likely has a mutation in which of the following chromosomes?

Answer: 11


Context: 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?

Question: Which of the following enzymes have the investigators most likely isolated?

Answer: DNA polymerase I


Context: 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?

Question: Which of the following is the most likely underlying cause of this patient's shortness of breath?

Answer: Hyperplasia of pulmonary vascular walls


Context: 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?

Question: 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


Context: 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?

Question: Which of the following can be expected on histopathological examination of the wounded area?

Answer: Deposition of type III collagen


Context: 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?

Question: The finding in this patient's ultrasonography increases the risk of which of the following conditions?

Answer: Gallbladder carcinoma


Context: 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?

Question: 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


Context: 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?

Question: Which of the following is the most likely cause of this finding?

Answer: Concentric left ventricular hypertrophy


Context: 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?

Question: Which of the following is the most appropriate next step in management?

Answer: Treat the patient with metronidazole


Context: 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?

Question: Infection with which of the following agents is the most likely cause of this patient's findings?

Answer: Hepatitis B


Context: 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?

Question: Which of the following is the most likely underlying mechanism of this patient's symptoms?

Answer: Inactivation of pancreatic enzymes


Context: 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?

Question: The patient's adrenal condition was most likely associated with which of the following symptoms?

Answer: Muscle weakness


Context:
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.
Laboratory test
Complete blood count
Hemoglobin 8.5 g/dL
MCV 82 fl
Leukocytes 13,500/mm3
Platelets 145,000/mm3
Basic metabolic panel
Serum Na+ 135 mEq/L
Serum K+ 3.9 mEq/L
Serum Cl- 101 mEq/L
Serum HCO3- 23 mEq/L
Liver function test
Serum bilirubin 2.8 mg/dL
Direct bilirubin 0.8 mg/dL
AST
30 U/L
ALT 35 U/L
Serum haptoglobin 23 mg/dL (41–165 mg/dL)
Ultrasonography of abdomen shows the following image. What is the pathogenesis of this ultrasound finding?

Question: What is the pathogenesis of this ultrasound finding?

Answer: Chronic hemolysis


Context: 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?

Question: Which of the following endocrine abnormalities would also most likely be found in this patient?

Answer: Insulin resistance


Context: 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?

Question: A biopsy of the hilar mass is most likely to show cells that stain positive for which of the following?

Answer: Neuron-specific enolase


Context: 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?

Question: Which of the following is most likely involved in the pathogenesis of this patient's skin findings?

Answer: Autoimmune destruction of melanocytes


Context: 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?

Question: Which of the following would be the best vector to provide gene therapy for this boy’s respiratory symptoms?

Answer: Adenovirus


Context: 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?

Question: What other sign or symptom is most likely present in this patient?

Answer: Loss of vibration sensation


Context: 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?

Question: 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


Context: 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?

Question: The pathogen most likely responsible for this patient’s current condition is also strongly associated with which of the following conditions?

Answer: Otitis externa


Context: 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?

Question: Which of the following findings confers the worst prognosis in this patient?

Answer: Mediastinal invasion


Context:
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.

Serum:
Na+: 139 mEq/L
Cl-: 100 mEq/L
K+: 3.9 mEq/L
HCO3-: 24 mEq/L
BUN: 22 mg/dL
Glucose: 41 mg/dL
Creatinine: 1.1 mg/dL
Ca2+: 10.2 mg/dL
C-peptide level: normal

Which of the following is the most likely diagnosis?

Question:
Serum:
Na+: 139 mEq/L
Cl-: 100 mEq/L
K+: 3.9 mEq/L
HCO3-: 24 mEq/L
BUN: 22 mg/dL
Glucose: 41 mg/dL
Creatinine: 1.1 mg/dL
Ca2+: 10.2 mg/dL
C-peptide level: normal

Which of the following is the most likely diagnosis?

Answer: Dumping syndrome


Context: 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?

Question: Coronary angiography is most likely to show narrowing of which of the following vessels?

Answer: Proximal right coronary artery


Context: 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?

Question: Coadministration with which of the following agents would be most likely to precipitate a deficiency of neutrophils in this patient?

Answer: Zidovudine


Context: 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?

Question: Infection with which of the following pathogens would most likely be prevented by these antibodies?

Answer: Parvovirus B19


Context: 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?

Question: Which of the following is the most likely diagnosis?

Answer: Seborrheic dermatitis


Context: 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?

Question: Which of the following characteristics is used to identify the offending organism?

Answer: Resistance to novobiocin


Context: 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?

Question: Which of the following is the most likely diagnosis?

Answer: Labyrinthitis


Context: 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?

Question: Which of the following is most likely to identify the underlying etiology of this patient's symptoms?

Answer: Colonoscopy


Context: 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?

Question: Which of the following is the most likely cause for the sonographic findings?

Answer: Penetrating duodenal ulcer


Context: 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?

Question: Which of the following is most likely to have prevented this patient's condition?

Answer: Vitamin B12 supplementation


Context: 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?

Question: Which of the following contraceptive methods is contraindicated in this patient?

Answer: Combined oral contraceptive pill


Context: 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?

Question: Which of the following is the most likely cause of the patient's condition?

Answer: Bleeding between dura mater and skull


Context: 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?

Question: Which of the following is the most likely diagnosis in this patient?

Answer: Central line-associated blood stream infection


Context: 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?

Question: Which of the following is the most appropriate pharmacotherapy at this time?

Answer: Ethosuximide


Context: 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?

Question: Which of the following is the most likely underlying cause of this patient's symptoms?

Answer: Neuronal degeneration due to α-synuclein protein misfolding


Context: 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?

Question: What is another likely finding in this patient?

Answer: Oxygen saturation of 99% on pulse oximetry


Context: 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?

Question: Further evaluation is most likely to show which of the following?

Answer: Anti-phospholipase A2 receptor antibodies


Context: 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?

Question: Which of the following is most appropriate next step in the management of this patient?

Answer:
Obtain throat culture
"


Context: 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?

Question: What is the best next step in management?

Answer: Give oxygen immediately


Context: 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?

Question: Over the next 5 years, which of the following complications is this patient most likely to develop?

Answer: Conjunctival telangiectasias


Context: 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?

Question: Which of the following processes is likely impaired in this patient?

Answer: Mismatch repair


Context:
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:
Hematocrit 37%
Leukocyte count 9000/mm3
Platelet count 60,000/mm3
Serum
Na+ 140 mEq/L
Cl- 104 mEq/L
K+ 4.4 mEq/L
Creatinine 1.0 mg/dL
Aspartate aminotransferase 20 U/L
Alanine aminotransferase 20 U/L
Which of the following is the most appropriate next step in management?"

Question:
Laboratory studies show:
Hematocrit 37%
Leukocyte count 9000/mm3
Platelet count 60,000/mm3
Serum
Na+ 140 mEq/L
Cl- 104 mEq/L
K+ 4.4 mEq/L
Creatinine 1.0 mg/dL
Aspartate aminotransferase 20 U/L
Alanine aminotransferase 20 U/L
Which of the following is the most appropriate next step in management?"

Answer: Magnesium sulfate and labetalol therapy


Context: 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?

Question: The tissue sample is most likely to show which of the following pathohistological findings?

Answer: Squamous cell carcinoma


Context:
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:
Hemoglobin 10.7 g/dL
Leukocyte count 4,100/mm3
Platelet count 155,000/mm3
Erythrocyte sedimentation rate 48 mm/h
Serum
Creatinine 1.0 mg/dL
Anti-nuclear antibody positive
Rheumatoid factor positive
Urinalysis is within normal limits. This patient's condition is most likely associated with which of the following antibodies?"

Question: This patient's condition is most likely associated with which of the following antibodies?"

Answer: Anti-Ro antibodies


Context: 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?

Question: Which of the following is the most likely diagnosis in this patient?

Answer: Idiopathic facial paralysis


Context: 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?

Question: This fetus is at increased risk for which of the following?

Answer: Cutis aplasia


Context: 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?

Question: Which of the following group of lymph nodes are most likely involved?

Answer: Para-aortic lymph nodes


Context:
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:
Total cholesterol 280 mg/dL
HDL-cholesterol 30 mg/dL
LDL-cholesterol 195 mg/dL
Triglycerides 275 mg/dL
Treatment with atorvastatin and cholestyramine is initiated. Which of the following changes is most likely induced by both agents?"

Question: Which of the following changes is most likely induced by both agents?"

Answer: Increased LDL receptor expression


Context: 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?

Question: Which of the following is the most likely causal pathogen?

Answer: Histoplasma capsulatum


Context: 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?

Question: The physician’s publication can be described as which of the following?

Answer: Case report


Context:
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:
Hemoglobin 17.6 g/dL
Reticulocytes 0.3%
Maternal blood group A, Rh-negative
Fetal blood group 0, Rh-positive
Serum
Bilirubin, total 7 mg/dL
Direct 0.6 mg/dL
Free T4 7 μg/dL
Which of the following is the most likely diagnosis?"

Question:
Laboratory studies show:
Hemoglobin 17.6 g/dL
Reticulocytes 0.3%
Maternal blood group A, Rh-negative
Fetal blood group 0, Rh-positive
Serum
Bilirubin, total 7 mg/dL
Direct 0.6 mg/dL
Free T4 7 μg/dL
Which of the following is the most likely diagnosis?"

Answer: Physiological neonatal jaundice


Context: 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?

Question: Which of the following is the most appropriate course of action?

Answer: Schedule more frequent follow-up visits


Context: 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?

Question: Which of the following properties is characteristic of this patient's most likely disorder?

Answer: Radiation of murmur to the axilla


Context: 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?

Question: Which of the following is the most likely diagnosis?

Answer: Frontotemporal dementia


Context: 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?

Question: This patient is most likely to develop which of the following in the future?

Answer: Meningioma


Context: 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?

Question: 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


Context: 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?

Question: What nerve was most likely injured during the procedure?

Answer: Ilioinguinal nerve


Context: 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?

Question: Which of the following is the most likely underlying cause of this patient's symptoms?

Answer: Urethral hypermobility


Context: 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?

Question: Which of the following is the most likely cause of this patient's symptoms?

Answer: Valve degeneration


Context: 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?

Question: Which of the following is the next best step in management?

Answer: Rapid strep test


Context: 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?

Question: Which of the following is the most likely diagnosis?

Answer: Granulosa cell tumor


Context: 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?

Question: What is the best next step in management for this patient?

Answer: Arthrocentesis