Abstract: FR-PO0449
An Atypical Case of Anti-GBM Disease with Insidious Onset
Session Information
- AKI: Case Reports - TMA, Vasculitis, Immune-Mediated Injury, and Systemic Disease
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Hutson, Stefan Charles, Lehigh Valley Hospital - Cedar Crest, Allentown, Pennsylvania, United States
- Zaidi, Syed Haris Mustafa, Lehigh Valley Hospital - Cedar Crest, Allentown, Pennsylvania, United States
- Chong, Grace Yun, Lehigh Valley Hospital - Cedar Crest, Allentown, Pennsylvania, United States
Introduction
Atypical anti-glomerular basement membrane (anti-GBM) disease is an autoimmune vasculitis that presents without circulating antibodies and with indolent progression. Kidney biopsy is essential for diagnosis and monitoring. This report describes persistent disease activity in a young woman despite aggressive multimodal immunosuppressive therapy.
Case Description
A 29-year-old woman with asthma and major depressive disorder presented in November 2023 with flank pain, gross hematuria, and proteinuria, with normal renal function and imaging. Nephrology evaluation showed persistent hematuria, proteinuria (PCR 2.09 g/g), preserved kidney function, and negative serologic testing, including anti-GBM antibodies. Kidney biopsy in July 2024 showed diffuse mesangial proliferative glomerulonephritis with one cellular crescent and linear IgG staining along the glomerular basement membrane without immune complex deposition, consistent with atypical anti-GBM disease. She was treated with mycophenolate mofetil and angiotensin receptor blockade, with only partial response and progressive urinary abnormalities. After discontinuation of MMF due to intolerance, she developed rapidly progressive kidney injury (creatinine 3.97 mg/dL). Repeat biopsy confirmed crescentic glomerulonephritis with persistent linear IgG staining. Treatment with corticosteroids, plasmapheresis, and cyclophosphamide resulted in renal recovery to baseline creatinine (1.2 mg/dL) over 9–12 months.
Discussion
Unlike classic anti-GBM disease, atypical anti-GBM disease often follows a more indolent course with preserved renal function and variable histopathology at presentation. It is frequently seronegative, and proposed mechanisms include antibodies targeting alternative GBM epitopes or less inflammatory IgG subclasses. Patients present with hematuria and proteinuria, though progression to crescentic glomerulonephritis may occur. Prognosis is more favorable than in classic disease, with improved renal survival. Treatment is not standardized and is extrapolated from conventional anti-GBM regimens, including corticosteroids, cyclophosphamide, and plasma exchange, tailored to biopsy findings and disease severity. Rituximab may be considered in refractory cases. Plasma exchange duration is uncertain due to variable responses. This case demonstrates progression from non-crescentic to crescentic disease despite immunosuppression, highlighting disease heterogeneity and need for more study.