Primary Angiitis of the Central Nervous System Presenting as a Cerebral Mass Lesion: A Case Report and Literature Review.

Primary angiitis of the central nervous system (PACNS) is a rare form of vasculitis and is confined entirely to the central nervous system (CNS)without systemic involvement. We report a rare case of PACNS in a 39-year-old female with new onset seizures and a right frontal enhancing mass. Initially the patient was thought to have a high-grade glioma and thus underwent a right frontal craniotomy for resection of right frontal mass. Intraoperatively, two fresh tissue samples were sent for intraoperative consultation. Sample 1 showed predominantly necrotic tissue and scant glial cells while sample 2 revealed glial tissue favoring gliosis versus low-grade neoplasm with necrosis and a few acute inflammatory cells. Final pathological diagnosis was consistent with PACNS. Postoperatively, the patient recovered well from surgery with no neurological deficits and was discharged on postoperative day 3. Two weeks after surgery the patient was started on cyclophosphamide and prednisone by Rheumatology. At one month follow up, the patient remained asymptomatic and seizure free.