A 10-year-old boy develops nephrotic syndrome 2 weeks after an upper respiratory infection. Renal biopsy shows diffuse thickening of the GBM on light microscopy. Immunofluorescence shows granular capillary wall deposits of IgG and C3. Electron microscopy shows subepithelial electron-dense deposits. The most likely diagnosis is:

• A Post-streptococcal glomerulonephritis
• B Membranous nephropathy ✓
• C MPGN type I
• D C3 glomerulopathy

Explanation

Subepithelial immune complex deposits with granular IgG and C3 on immunofluorescence and GBM thickening are characteristic of membranous nephropathy. Post-streptococcal GN shows subepithelial 'humps' but typically presents with nephritic syndrome, not nephrotic syndrome. MPGN shows mesangial and subendothelial deposits with double contours. C3 glomerulopathy lacks immunoglobulin deposits.

Reference: Brenner and Rector's The Kidney, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.