A 45-year-old woman with nephrotic syndrome and renal biopsy showing membranous nephropathy is anti-PLA2R antibody positive with proteinuria of 8 g/day. She has been on supportive therapy (ACE inhibitor, statins) for 6 months with no improvement. Which is now the first-line immunosuppressive therapy per KDIGO 2021?
- A Cyclophosphamide + steroids (Ponticelli regimen)
- B Cyclosporine A monotherapy
- C Rituximab ✓
- D Tacrolimus + low-dose steroids
Correct answer: C. Rituximab
Explanation
KDIGO 2021 Glomerular Disease guidelines recommend rituximab as the preferred first-line immunosuppressive therapy for primary membranous nephropathy in patients who fail to remit with 6 months of conservative treatment. The MENTOR trial (NEJM 2019) demonstrated that rituximab was superior to cyclosporine in inducing complete or partial remission at 24 months with more durable responses. Rituximab targets CD20 B cells, reducing PLA2R antibody production. The traditional Ponticelli regimen (cyclophosphamide alternating with methylprednisolone) remains an alternative.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.