Abstract: FR-PO0903
Phospholipase A2 Receptor (PLA2R)-Positive Membranous Lupus Nephritis: A Case of Overlapping Primary and Secondary Nephropathy
Session Information
- Glomerular Case Reports: Lupus, FSGS, Complement, and More
November 07, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Bai, Sadhna, LSU Health Shreveport, Shreveport, Louisiana, United States
- Kumar, Ravi, Lifecare Hospital Musaffah, Abu Dhabi, United Arab Emirates
- Kumar, Anand, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States
- Palleti, Sujith Kumar, LSU Health Shreveport, Shreveport, Louisiana, United States
- Sachdeva, Bharat, LSU Health Shreveport, Shreveport, Louisiana, United States
Introduction
Primary membranous nephropathy (PMN) represents an autoimmune glomerular disease and is recognized as a leading cause of nephrotic syndrome in adults. It is characteristically associated with the presence of circulating anti-PLA2R antibodies and the deposition of subepithelial immune complexes. In contrast, membranous lupus nephritis (class V) constitutes a secondary form that is associated with systemic lupus erythematosus (SLE). This condition is typically negative for PLA2R and exhibits a "full-house" immunofluorescence pattern. In rare instances, features of both conditions may coexist, presenting diagnostic and therapeutic challenges.
Case Description
We present the case of a 37-year-old African American woman with no history of hypertension or diabetes, who developed progressive bilateral leg edema.
Initial labs revealed nephrotic-range proteinuria (UPCR 13 g/g), hypoalbuminemia, (1.5 g/dL), elevated serum Cr (2.9 mg/dL), cystatin C 1.7, and positive autoimmune markers (ANA, SSA, intermediate dsDNA) with normal complement levels. Serum PLA2R was negative. Renal biopsy confirmed membranous lupus nephritis (ISN/RPS Class V) with 25–30% tubulointerstitial fibrosis and moderate mesangial hypercellularity. Immunofluorescence showed granular IgG (3+), IgM (2+), IgA (1+), C3 (2+), kappa (3+), and lambda (3+) staining, with negative C1q and fibrinogen. EM demonstrated basement membrane thickening and diffuse foot process effacement. PLA2R staining was diffusely positive along capillary basement membranes.
Discussion
This case highlights a rarely reported instance of PLA2R-positive membranous features in a patient with class V lupus nephritis, suggesting potential overlap between primary and secondary forms of membranous nephropathy. It underscores the importance of integrating clinical, serological, and histopathologic data in evaluating nephrotic syndrome and calls attention to emerging evidence that PLA2R expression may not be exclusive to idiopathic disease. Recognition of such overlap has implications for disease classification, pathogenesis, and management strategies.The patient responded well to treatment with MMF, steroids, and ACE inhibitors, showing clinical improvement marked by reduced proteinuria and improved serum creatinine, with continued follow-up planned to monitor progress.