Abstract

Diffuse Lewy body disease is an important pathological substrate of the common syndrome of parkinsonian dementia. The new technique of anti-ubiquitin immunocytochemistry has been used in a correlative quantitative neuropathological study of fifteen cases of diffuse Lewy body disease, showing that the severity of dementia is related to cortical Lewy body density, whilst subcortical abnormalities make a much less significant contribution. Cortical senile plaques also appear to be part of the pathology of diffuse Lewy body disease and should not therefore be used as an isolated diagnostic criterion for Alzheimer's disease. Diagnostic criteria for diffuse Lewy body disease are discussed.