A 42-year-old man with biopsy-proven membranous nephropathy and proteinuria of 8 g/day develops sudden left flank pain and gross hematuria. Blood pressure is 150/95 mmHg. Urinalysis shows red cells without casts. The next best investigation to establish the cause is:
- A Doppler ultrasound of renal veins ✓
- B CT urography for calculus
- C Renal angiography
- D Micturating cystourethrogram
Correct answer: A. Doppler ultrasound of renal veins
Explanation
Membranous nephropathy carries the highest risk of renal vein thrombosis among glomerular diseases because urinary losses of antithrombin III and altered fibrinolytic factors create a hypercoagulable state. New flank pain, gross hematuria, or abrupt worsening of proteinuria in a nephrotic patient mandates renal vein Doppler imaging. Calculus disease does not explain the nephrotic context, and angiography evaluates arterial, not venous, patency.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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