Primary Central Nervous System Vasculitis Following Alemtuzumab Treatment for Multiple Sclerosis: A Case Report and Literature Review.

INTRODUCTION: Cerebral vasculitides are often devastating conditions that require immediate diagnosis and treatment. CASE REPORT: We report a pathologically proven clinical case of primary central nervous system vasculitis in a 50-year-old man with a diagnosis of relapsing-remitting multiple sclerosis after alemtuzumab therapy, which required additional immunosuppression to control this life-threatening condition. CONCLUSION: In patients presenting subacute neurological deterioration after alemtuzumab therapy, primary central nervous system vasculitis should be considered as a differential diagnosis among other autoimmune conditions.