Biopsy-proven isolated sarcoid meningitis. Case report.

Neurosarcoidosis without systemic involvement is rare and difficult to diagnose. The case of a 27-year-old man with a 6-week history of headache, mental status changes, and polyradiculopathy attributable to hypoglycorrheic lymphocytic meningitis is presented. Extensive testing for occult systemic sarcoidosis was negative. The presence of noncaseating granulomatous inflammation was established by open brain biopsy, and the patient improved clinically with oral steroid therapy. In individuals with undiagnosed chronic meningitis, brain biopsy may be necessary to rule out isolated neurosarcoidosis.