Abstract: FR-PO0748
Refractory Anti-GBM Disease with Persistent Serologic Activity and Ultrastructural GBM Remodeling
Session Information
- Glomerular Diseases: ANCA Vasculitis, Anti-GBM Disease, and Crescentic GN
October 23, 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
- Vera, Duhlicher, Institutul Clinic Fundeni, Bucharest, Bucharest, Romania
- Lazar, Ionela, Institutul Clinic Fundeni, Bucharest, Bucharest, Romania
- Lujinschi, Stefan Nicolaie, Institutul Clinic Fundeni, Bucharest, Bucharest, Romania
- Ismail, Gener, Institutul Clinic Fundeni, Bucharest, Bucharest, Romania
Introduction
Anti-GBM disease is a rapidly progressive glomerulonephritis characterized by linear IgG deposition, with immune complex deposits typically absent. However, persistent serologic activity and atypical structural changes remain poorly characterized.
Case Description
A 21-year-old male presented with severe pulmonary–renal syndrome, including diffuse alveolar hemorrhage requiring ventilation and dialysis-dependent kidney injury, with anti-GBM titers >1500 U/mL. Initial steroids, cyclophosphamide, and plasma exchange improved respiratory but not renal status. Due to persistent serologic activity, therapy was escalated with rituximab, achieving sustained B-cell depletion, alongside C5 complement inhibition. After 6 months, anti-GBM antibodies remained detectable (23 U/mL) despite partial recovery with preserved diuresis and reduction to twice-weekly hemodialysis. HLA typing showed DRB115:01 and DRB103:01 risk haplotypes. Kidney biopsy revealed crescentic glomerulonephritis with global sclerosis. Electron microscopy showed irregular GBM thickening with intramembranous resorbed deposits, suggesting chronic immune-mediated GBM remodeling rather than membranous nephropathy (Figure 1). Anti-PLA2R antibodies were negative.
Discussion
Persistent anti-GBM activity despite complete B-cell depletion and complement inhibition suggests antibody production from long-lived plasma cells. Ultrastructural findings support secondary GBM remodeling due to sustained immune injury. Persistent serologic activity despite partial renal recovery suggests a dissociation between antibody levels and renal injury. This case highlights persistent anti-GBM serologic activity with chronic ultrastructural GBM remodeling despite intensive therapy, expanding the spectrum of structural lesions observed in refractory anti-GBM disease.