Abstract: SA-PO0803
Not All Positive Lupus Serologies Are Lupus Nephritis: Anti-Nephrin-Related Minimal Change Disease Presenting as a Lupus Mimicker
Session Information
- Glomerular Diseases: Lupus Nephritis, Monoclonal Gammopathy-Related Disease, and Transplantation
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Naseem, Anam, Mercy Fitzgerald Hospital, Darby, Pennsylvania, United States
- Abate, Daniel B., Mercy Fitzgerald Hospital, Darby, Pennsylvania, United States
- Itoo, Usman Bashir Ahmed, Mercy Fitzgerald Hospital, Darby, Pennsylvania, United States
- Rather, Manzoor, Mercy Fitzgerald Hospital, Darby, Pennsylvania, United States
Introduction
Nephrotic-range proteinuria with positive ANA, anti-dsDNA antibodies, and hypocomplementemia strongly suggests lupus nephritis (LN). Anti-nephrin autoantibody–associated minimal change disease (MCD) is an autoimmune podocytopathy that can clinically and serologically mimic LN while carrying distinct therapeutic implications. We present a case of anti-nephrin–related MCD requiring renal biopsy for definitive diagnosis.
Case Description
A 62-year-old Black woman with hypertension presented with one week of vomiting, diarrhea, poor oral intake, and abdominal discomfort. Labs revealed AKI (creatinine 2.1 mg/dL, baseline 0.5 mg/dL), BUN 112 mg/dL, hyperkalemia, hyponatremia, non-anion-gap metabolic acidosis, leukopenia, thrombocytopenia, and hypoalbuminemia. CT showed mild anasarca without obstruction. Further workup demonstrated nephrotic-range proteinuria (UPCR 3.5), microscopic hematuria, hyperlipidemia, low C3/C4, positive ANA, and positive anti-dsDNA. HIV, hepatitis B/C, ANCA, and anti-GBM were negative.
Renal biopsy showed preserved glomerular architecture with swollen podocytes, without fibrinoid necrosis, tubular atrophy, or interstitial fibrosis. Electron microscopy confirmed diffuse foot process effacement without subepithelial, subendothelial, or mesangial immune deposits. Immunofluorescence demonstrated trace "powdery" IgG localized to podocytes — the histopathologic signature of anti-nephrin–mediated podocytopathy—without capillary wall immune complex deposition. Findings were consistent with MCD. The patient received pulse-dose IV methylprednisolone followed by oral prednisone with gradual renal recovery.
Discussion
Anti-nephrin–associated MCD can be clinically indistinguishable from LN, sharing positive ANA, anti-dsDNA, hypocomplementemia, nephrotic-range proteinuria, hematuria, and anasarca. Circulating anti-nephrin autoantibodies are identified in approximately 45–50% of active MCD cases, supporting a distinct autoimmune podocytopathy. Renal biopsy — with attention to the podocyte-localized IgG pattern on immunofluorescence and absence of immune complex deposits on electron microscopy — is essential for accurate diagnosis. The distinction carries critical therapeutic implications: while corticosteroids overlap initially, anti-nephrin MCD may respond to rituximab, avoiding unnecessary escalation to LN-directed immunosuppressive regimens.