Etanercept-Induced Anti-Glomerular Basement Membrane Disease

Area of Science:

• Nephrology
• Rheumatology
• Immunology

Background:

• Anti-glomerular basement membrane (anti-GBM) disease is a rare small-vessel vasculitis causing rapidly progressive glomerulonephritis.
• Tumor necrosis factor-alpha (TNF-α) antagonists are increasingly used for inflammatory conditions.
• Drug-induced anti-GBM disease is exceptionally rare, with only one prior report linked to TNF-α antagonists.

Observation:

• A 55-year-old man on etanercept for psoriatic arthropathy presented with painless macroscopic hematuria.
• Elevated anti-GBM antibody titers and crescentic glomerulonephritis confirmed the diagnosis.
• The patient developed COVID-19 during treatment, complicating management.

Findings:

• This is the first reported case of etanercept-induced anti-GBM disease.
• Treatment involved stopping etanercept, pulsed methylprednisolone, cyclophosphamide, and plasma exchange.
• Despite complications, the patient's renal function improved, becoming dialysis-independent after switching to rituximab.

Implications:

• Clinicians must be aware of the potential for rare but severe drug-induced vasculitis with TNF-α antagonists like etanercept.
• Close monitoring of renal function is recommended during treatment with these agents.
• This case highlights the importance of considering drug etiology in vasculitis presentations.