Anti-glomerular basement membrane (anti-GBM) disease
Anti-glomerular basement membrane (anti-GBM) disease is a rare, rapidly progressive glomerulonephritis caused by circulating antibodies against the alpha-3 chain of type IV collagen, presenting with hematuria, acute kidney injury, and, in over half of patients, pulmonary hemorrhage (Goodpasture syndrome). Kidney biopsy showing crescentic glomerulonephritis with linear IgG staining plus a positive serum anti-GBM antibody confirms the diagnosis, and outcome depends critically on early treatment with plasma exchange, pulse glucocorticoids, and cyclophosphamide before dialysis dependence and diffuse crescents set in.
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What this article covers
- Overview
A rare autoantibody-mediated pulmonary-renal syndrome: anti-glomerular basement membrane (anti-GBM) disease is caused by circulating antibodies directed against the alpha-3 chain of type IV collagen…
- Epidemiology
Incidence is less than one case per million per year, making anti-GBM disease the rarest of the major RPGN etiologies.
- Risk factors
No environmental or exposure-based risk factor is established; the disease is autoantibody-driven rather than linked to a specific trigger.
- Pathophysiology
Circulating anti-GBM antibodies target the alpha-3 chain of type IV collagen, a structural protein present in the glomerular basement membrane and, because of shared antigenic structure, the alveolar basement membrane.
- Clinical features
Macroscopic or microscopic hematuria with erythrocyte casts is a hallmark finding, reflecting active glomerular inflammation, as in other forms of RPGN.
- Differential diagnosis
ANCA-associated glomerulonephritis: distinguished by pauci-immune (rather than linear) staining on kidney biopsy immunofluorescence; positive ANCA serology (usually anti-MPO or anti-PR3) supports…
- Diagnosis
Anti-GBM disease is confirmed by kidney biopsy showing crescentic glomerulonephritis on light microscopy with pathognomonic linear IgG staining along the glomerular capillaries on immunofluorescence…
- Management
First, initiate treatment as early as possible once anti-GBM disease is suspected, without waiting for biopsy confirmation if clinical suspicion is high and the patient is deteriorating, because…
- Complications
Progression to dialysis-dependent end-stage kidney disease, the dominant risk in patients presenting with severe acute kidney injury or a high percentage of circumferential crescents.
- Prognosis
Outcome is determined largely by the degree of acute kidney injury at diagnosis and treatment, more than by any other single factor.
- Prevention
There is no established primary prevention, since anti-GBM disease has no known modifiable environmental trigger; the actionable prevention target is early recognition and treatment to prevent irreversible kidney and lung injury.
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