GERSTMANN-STRAUSSLER-SCHEINKER DISEASE SHOWING BETA-PROTEIN TYPE CEREBELLAR AND CEREBRAL AMYLOID ANGIOPATHY

Cerebral amyloid angiopathy is observed in several brain degenerative disorders, but this pathological condition has received little attenti on in Gerstmann-Straussler-Scheinker disease (GSS). We report a 69-yea r-old man who showed the cardinal features of GSS together with typica l and extensive congophilic angiopathy. Immunohistochemical studies re vealed that the vast majority of the amyloid plaques present in the br ain of this patient were consistently labeled by anti-prion protein (P rP) antibody. Double immunostaining disclosed many additional beta-pro tein immunoreactive plaque-like lesions, including a special type of ' 'hybrid'' plaque with colocalization of PrP and beta-protein (beta-PrP ). The vascular amyloid deposits seen in both the cerebellum and cereb rum were immunoreactive only to anti-beta-protein antibody. It seems l ikely that the extensive deposition of beta-protein amyloid (including brain vascular amyloidosis) seen in this and other similar cases is p art of pathology of GSS, although the possibility that this finding is due to ageing or concomitant Alzheimer's disease cannot be completely ruled out.