Lobar atrophy without Pick bodies.

Four patients from the Kathleen Price Bryan Brain Bank with clinical Pick's syndrome are presented. Thorough neurological evaluation revealed no evidence of a movement disorder. The brains showed marked knife-blade type atrophy of the frontal and temporal lobes with relative sparing of the superior temporal gyrus and parietal and occipital lobes. There was marked caudate atrophy in all four. Histologically there was severe neuronal loss and gemistocytic astrocytosis in the involved areas with marked myelin pallor in the deep white matter and subcortical gliosis. There was sometimes marked spongiform change in cortical layer 2. There was severe neuronal loss and gliosis of the caudate nucleus. The gross and microscopic features were characteristic of Pick's disease except that careful search failed to uncover either Pick's bodies or Pick's cells. Review of the literature revealed that fronto-temporal cortical and caudate atrophy with clinical features of Pick's disease has received many different names including Pick's disease type C, Pick's disease type II, progressive subcortical gliosis, presenile glial dystrophy, long duration Creutzfeldt-Jakob disease, frontal lobe degeneration, dysphasic dementia, and dementia lacking distinctive histologic features. Nevertheless, the morphologic findings in the present cases so closely resemble Pick's disease that they may well represent endstage Pick's disease. In our experience, such cases account for a significant proportion of non-Alzheimer disease dementia.