USMLE Clinical Medicine 2

Question 1

A 50-year-old man with a history of GERD presents with progressive dysphagia, first to solids then liquids, and weight loss. Endoscopy shows a mucosal irregularity. What is the most likely diagnosis?

Accepted Answer

Esophageal carcinoma

Answer

Progressive dysphagia starting with solids then progressing to liquids combined with weight loss is the classic presentation of esophageal carcinoma; GERD is a risk factor for adenocarcinoma.

Question 2

A patient taking lithium develops signs of toxicity including coarse tremor, confusion, and cardiac arrhythmias. What electrolyte abnormality predisposes to lithium toxicity?

Accepted Answer

Hyponatremia

Answer

Hyponatremia (from diuretics, low-sodium diet, or dehydration) causes the kidney to reabsorb lithium in place of sodium in the proximal tubule, increasing lithium levels and toxicity.

Question 3

A patient presents with periorbital and peripheral edema, massive proteinuria (>3.5 g/day), hypoalbuminemia, and hyperlipidemia. What is this syndrome?

Accepted Answer

Nephrotic syndrome

Answer

Nephrotic syndrome is defined by the triad of massive proteinuria (>3.5 g/day), hypoalbuminemia, and edema, with hyperlipidemia and lipiduria as secondary features.

Question 4

A patient with suspected meningitis undergoes lumbar puncture. CSF shows low glucose, high protein, and predominantly lymphocytes. What is the most likely etiology?

Accepted Answer

Tuberculous meningitis

Answer

Tuberculous meningitis typically shows low glucose, high protein, and lymphocytic pleocytosis in CSF, along with a subacute course, compared to the acute neutrophilic presentation of bacterial meningitis.

Question 5

A 25-year-old woman has amenorrhea, elevated prolactin, and bitemporal hemianopia. MRI shows a pituitary mass. What is the diagnosis?

Accepted Answer

Prolactinoma

Answer

Prolactinoma (most common pituitary adenoma) secretes excess prolactin causing galactorrhea, amenorrhea/infertility in women, and compresses the optic chiasm causing bitemporal hemianopia.

USMLE Practice Test

USMLE Practice Test

USMLE Clinical Medicine 2