A 28-year-old man with a recent sore throat now presents with haematuria, red cell casts, hypertension, and mild oliguria 2 weeks later. Serum C3 is low; ASO titre is elevated. Which lesion is most likely seen on renal biopsy?

• A Segmental sclerosis and hyalinosis affecting some glomeruli
• B Mesangial IgA deposits with focal segmental proliferation
• C Diffuse endocapillary hypercellularity with subepithelial 'hump' deposits on EM ✓
• D Crescentic GN with linear IgG along GBM

Explanation

The clinical picture describes post-streptococcal (post-infectious) GN — nephritic syndrome 1–3 weeks after streptococcal pharyngitis with low C3 and elevated ASO. Biopsy shows diffuse endocapillary hypercellularity (neutrophils, monocytes) on LM and pathognomonic subepithelial electron-dense deposits ('humps') on EM with granular IgG and C3 on IF. FSGS lacks the post-infectious context; Goodpasture shows linear IgG.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.