A 42-year-old man with biopsy-proven primary membranous nephropathy presents with sudden left flank pain and gross haematuria. Doppler ultrasound shows absent flow in the left renal vein. Which complication of nephrotic syndrome has most likely occurred?

• A Renal vein thrombosis ✓
• B Renal artery embolism
• C Papillary necrosis
• D Cholesterol crystal embolisation

Explanation

Membranous nephropathy carries the highest risk of renal vein thrombosis among the nephrotic syndromes because urinary loss of antithrombin III plus increased fibrinogen and platelet hyperactivity create a hypercoagulable state. Flank pain with gross haematuria and absent venous flow confirms it. Renal artery embolism causes pain without venous occlusion, papillary necrosis occurs mainly in analgesic abuse, diabetes and sickle cell disease, and cholesterol embolisation follows endovascular procedures.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.