The clinical features of diffuse Lewy body disease (DLBD) in the elderly were retrospectively reviewed in 12 cases which had been diagnosed on pathological grounds. Their ages at onset and at death were between 60 and 85 years and between 76 and 92 years respectively. All of them had dementia of mild to severe degree, and eight presented with persistent severe hallucination-delusion psychosis with or without delirium. A single case presented with symptoms typical of Parkinson's disease including resting tremor, cogwheel rigidity and akinesia, while four of them showed no parkinsonian features. In the other seven, dementia or psychosis was followed by rigidity and akinesia at a late stage in the disease. Four had a history of orthostatic hypotension with syncope reminiscent of Shy-Drager syndrome. One can suspect DLBD when an elderly patient presents with atypical dementia of varying degrees, in combination with any of persistent delusion-hallucination psychosis, mild parkinsonism, and orthostatic syncope or dizziness.
Diffuse Lewy body disease (DLBD) is a neuropathological entity in which abundant Lewy bodies (LBs) are found throughout the cerebral cortex, as well as in the brainstem nuclei in a manner identical to that seen in Parkinson's disease (Kosaka et al., 1980; Kosaka et al., 1984). Marked senile changes including abundant senile plaques and Alzheimer neurofibrillary tangles of diverse degree are also found in the elderly patients.