Goodpasture's Syndrome Following Radiation Exposure: A Rare Pulmonary-Renal Complication.

Goodpasture's syndrome (anti-glomerular basement membrane (anti-GBM) disease) is a rare, life-threatening autoimmune condition characterized by rapidly progressive glomerulonephritis and pulmonary hemorrhage. We describe a woman in her 60s with a history of breast cancer treated with lumpectomy and radiotherapy who developed hemoptysis, hematuria, acute kidney injury, and respiratory failure. She lacked traditional environmental risk factors, like cigarette smoking, hydrocarbon exposure, respiratory infections, and inhalational lung injury associated with anti-GBM disease. Diagnosis was established through positive circulating anti-GBM antibodies and a confirmatory lung biopsy demonstrating linear IgG deposition along the alveolar basement membrane. Her course was complicated by respiratory failure requiring tracheostomy, recurrent infections, anemia, and transient dialysis dependence. The patient improved following aggressive immunosuppression, plasmapheresis, and supportive care. This case highlights the diagnostic challenges of anti-GBM disease in critically ill patients, and although a causal relationship cannot be established from a single case, we evaluate how prior radiotherapy may have contributed to disease development in a susceptible individual.