COMSAE Renal and Urological Systems

Question 1

A patient presents with oliguria, hematuria, and periorbital edema 2-3 weeks after a streptococcal throat infection. Urinalysis shows RBC casts. What is the most likely diagnosis?

Accepted Answer

Post-streptococcal glomerulonephritis

Answer

IgA nephropathy

Answer

Nephrotic syndrome

Answer

Acute tubular necrosis

Question 2

On COMSAE, which diuretic is most appropriate for a patient with heart failure and severe symptomatic edema requiring rapid fluid removal?

Accepted Answer

Furosemide (loop diuretic)

Answer

Hydrochlorothiazide

Answer

Spironolactone

Answer

Acetazolamide

Question 3

A 65-year-old man with diabetes presents with creatinine 3.2 mg/dL, hyperkalemia, and metabolic acidosis with a normal anion gap. Which acid-base disorder is most likely?

Accepted Answer

Type 4 renal tubular acidosis (hyperkalemic RTA)

Answer

Type 1 RTA (distal)

Answer

Type 2 RTA (proximal)

Answer

High anion gap metabolic acidosis

Question 4

Which finding best distinguishes prerenal azotemia from acute tubular necrosis (ATN)?

Accepted Answer

Fractional excretion of sodium (FENa) < 1%

Answer

BUN:Cr ratio < 15

Answer

Muddy brown casts in urine

Answer

FENa > 2%

Question 5

A 30-year-old man presents with recurrent hematuria coinciding with upper respiratory infections (synpharyngitic hematuria). Kidney biopsy shows mesangial IgA deposits. What is the diagnosis?

Accepted Answer

IgA nephropathy (Berger disease)

Answer

Post-streptococcal GN

Answer

Henoch-Schönlein purpura nephritis

Answer

Alport syndrome

Question 6

Which electrolyte abnormality is the most immediately life-threatening complication of acute renal failure requiring emergent treatment?

Accepted Answer

Hyperkalemia

Answer

Hyponatremia

Answer

Hyperphosphatemia

Answer

Hypocalcemia