Subarachnoid hemorrhage and cerebral infarction in anti-glomerular basement membrane disease: a case report and literature review.

Anti-glomerular basement membrane (anti-GBM) disease is a rare autoimmune disorder characterized by rapidly progressive glomerulonephritis, with or without pulmonary hemorrhage. Central nervous system (CNS) involvement is exceedingly uncommon, and intracranial subarachnoid hemorrhage (SAH) has rarely been described in association with anti-GBM disease. We report a rare case of anti-GBM disease complicated by intracranial SAH and subsequent cerebral infarction. A 53-year-old woman presented with fever and headache and rapidly developed acute kidney injury with markedly elevated anti-GBM antibody titers. Renal biopsy confirmed anti-GBM disease. Despite treatment with plasma exchange and high-dose corticosteroids, renal function deteriorated, and the patient became dialysis-dependent. Rituximab was added to achieve serological control after an insufficient response to conventional therapy. During the clinical course, the patient developed a generalized seizure and was diagnosed with intracranial SAH, followed later by a subacute cerebral infarction. Cerebral angiography revealed no aneurysms or vascular malformations. Blood pressure had remained stable prior to the neurological event. Following intensive management, including continued plasma exchange, rituximab, corticosteroids, and strict blood pressure control, no neurological sequelae were observed. Anti-GBM antibody titers gradually declined, although renal function did not recover. This case illustrates a rare occurrence of intracranial subarachnoid hemorrhage as a central nervous system complication in anti-GBM disease and highlights the importance of careful neurological monitoring.