COMSAE Renal and Urinary Systems

Question 1

A patient with chronic kidney disease has a GFR of 22 mL/min/1.73 m². According to KDIGO staging, what CKD stage is this?

Accepted Answer

Stage 4

Answer

KDIGO defines CKD Stage 4 as GFR 15–29 mL/min/1.73 m², which corresponds to severely decreased kidney function.

Question 2

Which urinalysis finding is most characteristic of nephrotic syndrome?

Accepted Answer

Massive proteinuria (>3.5 g/day)

Answer

Nephrotic syndrome is defined by proteinuria >3.5 g/day, hypoalbuminemia, edema, and hyperlipidemia.

Question 3

A patient presents with oliguria, flank pain, and hematuria after starting an NSAID. Urinalysis shows muddy brown casts and elevated BUN/creatinine. What type of acute kidney injury is this?

Accepted Answer

Intrinsic renal AKI (ATN)

Answer

NSAIDs reduce prostaglandin-mediated afferent arteriole dilation, causing ischemia and acute tubular necrosis, characterized by muddy brown granular casts.

Question 4

Which feature best distinguishes prerenal AKI from intrinsic renal AKI?

Accepted Answer

BUN:creatinine ratio >20:1 and FeNa <1%

Answer

In prerenal AKI the tubules are intact so they avidly reabsorb sodium (FeNa <1%) and urea, raising the BUN:creatinine ratio above 20:1.

Question 5

The sympathetic nervous system innervates the kidney via which spinal levels, relevant to osteopathic viscerosomatic reflexes?

Accepted Answer

T10–L1

Answer

Renal sympathetic innervation originates from T10–L1, and somatic dysfunction at these levels can reflect renal pathology through viscerosomatic reflex arcs.

COMSAE - Comprehensive Osteopathic Medical Self-Assessment Examination Practice Test

COMSAE - Comprehensive Osteopathic Medical Self-Assessment Examination Practice Test

COMSAE Renal and Urinary Systems