A 55-year-old woman with nephrotic syndrome (proteinuria 8 g/day, albumin 1.9 g/dL) has a renal biopsy showing glomerular capillary wall 'spike and dome' deposits by silver stain, with subepithelial electron-dense deposits on EM, and granular IgG and C3 deposits on immunofluorescence. Anti-PLA2R antibody is positive. The first-line treatment is:

• A Rituximab (anti-CD20) ✓
• B High-dose prednisolone alone
• C Cyclophosphamide plus prednisolone (Ponticelli regimen)
• D Tacrolimus monotherapy

Explanation

Primary membranous nephropathy (anti-PLA2R positive) has rituximab as the preferred first-line immunosuppressive agent per current KDIGO 2021 guidelines, based on the MENTOR trial showing rituximab superior to cyclosporine for inducing complete remission with a more favorable side-effect profile. The Ponticelli cyclophosphamide regimen was the historical standard and remains an alternative. Steroids alone are insufficient in membranous nephropathy. Tacrolimus achieves partial remissions but has high relapse rates on withdrawal.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.