Crystalline encephalopathy: Cerebral immunoprotein deposits and isolated angiitis

Abstract

Brain biopsy specimens from a 38‐year‐old woman with adversive seizures and bifrontal mass lesions evident on computed tomographic scans showed extracellular and intracellular deposits of crystallized protiens. These were morphologically identical to the immunoglobylin crystals seen in reactive or neoplastic plasma cells and by peroxidase‐antiperoxidase methods were found to contrain polyclonal immunoglobulins. In addition, severe angiitis of the intracerebral blood vessels was present.