COMSAE Renal and Urinary Systems 2 — Questions and Answers
Question 1: A 25-year-old man has gross hematuria, hearing loss, and a family history of renal failure. Electron microscopy shows thinning and splitting of the glomerular basement membrane. What is the diagnosis?
- IgA nephropathy
- Alport syndrome (Correct answer)
- Minimal change disease
- Membranous nephropathy
Correct answer: Alport syndrome
Alport syndrome is an X-linked hereditary nephritis caused by mutations in type IV collagen genes, presenting with hematuria, sensorineural hearing loss, and characteristic GBM splitting.
Question 2: What is the most common cause of nephrotic syndrome in US adults?
- Minimal change disease
- Focal segmental glomerulosclerosis
- Membranous nephropathy
- Diabetic nephropathy (Correct answer)
Correct answer: Diabetic nephropathy
Diabetic nephropathy is the leading cause of nephrotic syndrome and end-stage renal disease in adults in the United States.
Question 3: Renal tubular acidosis type 1 (distal RTA) is associated with which metabolic abnormality?
- Normal anion gap metabolic acidosis with inability to acidify urine below pH 5.5 (Correct answer)
- High anion gap metabolic acidosis
- Metabolic alkalosis with hypokalemia
- Normal anion gap acidosis with alkaline urine and hyperkalemia
Correct answer: Normal anion gap metabolic acidosis with inability to acidify urine below pH 5.5
Distal RTA involves a defect in H+ secretion in the collecting duct, resulting in inability to lower urine pH below 5.5 despite systemic acidosis.
Question 4: A patient with a kidney stone passes it spontaneously and analysis shows calcium oxalate composition. Which dietary modification is most evidence-based?
- Low-calcium diet
- High-protein diet
- Increased fluid intake to >2.5 L/day (Correct answer)
- Low-potassium diet
Correct answer: Increased fluid intake to >2.5 L/day
Increased hydration to produce >2.5 L of urine daily is the most universally effective dietary intervention to prevent recurrent nephrolithiasis.
Question 5: Which osteopathic technique is indicated to address lymphatic drainage of the renal and pelvic region?
- Cervical soft tissue
- Thoracic pump technique
- Pelvic diaphragm release (Correct answer)
- Occipital decompression
Correct answer: Pelvic diaphragm release
The pelvic diaphragm release improves lymphatic and venous drainage from the pelvic and lower abdominal viscera including the kidneys.
Question 6: In a patient with ESRD, which chronic complication results from impaired renal conversion of 25-OH vitamin D to its active form?
- Metabolic alkalosis
- Renal osteodystrophy (Correct answer)
- Nephrotic syndrome
- Hyperkalemia
Correct answer: Renal osteodystrophy
Loss of 1-alpha hydroxylase activity in the kidney prevents conversion of 25-OH vitamin D to 1,25-(OH)₂ vitamin D (calcitriol), leading to hypocalcemia, secondary hyperparathyroidism, and renal osteodystrophy.
COMSAE Renal and Urinary Systems 2
A 25-year-old man has gross hematuria, hearing loss, and a family history of renal failure.
Electron microscopy shows thinning and splitting of the glomerular basement membrane.
What is the diagnosis?