A case of isolated neurosarcoidosis associated with psychosis.

Sarcoidosis is a multisystem inflammatory disease of unknown etiology. Isolated neurosarcoidosis without signs of systemic involvement has rarely been reported in the literature. We report a case of isolated neurosarcoidosis that presented with psychiatric symptoms and headache. Cranial MRI revealed bilateral diffuse high intensity lesions in the deep white matter, with a linear contrast enhancement of perivascular areas. Histological examination of a stereotactic brain biopsy specimen demonstrated noncaseating granulomas. Further research did not reveal any evidence of systemic disease. The patient was treated with corticosteroids and responded well to medical therapy. The diagnosis of isolated neurosarcoidosis is a challenge and may require histological examination.