Delirium and isolated angiitis of the central nervous system: a case report and review.

Central nervous system (CNS) vasculitis is a rare entity, especially when it occurs in isolation; it is seen more commonly as part of a multisystem vasculitis. Common presenting symptoms include persistent headache, encephalopathy, and multifocal signs. We discuss the case of a 68-year-old female who presented twice in 1 month with confusion and choreaform movements. Extensive workup was negative for a connective tissue disease or other conditions in the differential, including neurosarcoidosis, Creutzfeldt-Jakob disease, and neurosyphilis. The only significant findings were elevated erythrocyte sedimentation rate, inflammatory signs in the CNS, and diffuse slowing of the electroencephalogram. A presumptive diagnosis of isolated angiitis of the central nervous system (IACNS) was made and the patient was successfully treated with steroids. She recovered fully with no residual symptoms. The diagnosis of IACNS is often difficult given there are no definitive laboratory investigations or pathognomonic presentation. However, a series of signs, symptoms, and laboratory findings have been proposed that are helpful in making the diagnosis. To our knowledge, IACNS presenting primarily with delirium has not been previously reported in the literature. The diagnosis of IACNS is purely speculative for this case, as the gold standard for diagnosis, a leptomeningeal cortical biopsy, was not performed.