DIFFUSE LEWY BODY DISEASE - CLINICAL-FEATURES IN 9 CASES WITHOUT COEXISTENT ALZHEIMERS-DISEASE

Objective-To further elucidate the relation between diffuse Lewy body disease and Parkinson's disease. Methods and results-The clinical feat ures of nine cases of pure diffuse Lewy body disease without pathologi cal evidence of coexisting Alzheimer's neuritic pathology are reported . All patients were aged less than 70 years at onset (mean 62 years). Five patients presented with clinical features, which included assymet ric resting tremor and levodopa responsiveness, which were initially i ndistinguishable from idiopathic Parkinson's disease. All five patient s later became demented (mean of three years after presentation). Two further patients presented with parkinsonism and dementia and two pati ents presented with dementia and developed parkinsonism at a later sta ge. Hallucinations appeared 2.5-9 years after the onset of symptoms in six patients and were a presenting feature in one patient. All patien ts met the pathological criteria of idiopathic Parkinson's disease, wi th respect to the midbrain changes, in addition to having diffuse cort ical Lewy bodies. Conclusions-Diffuse Lewy body disease may present as parkinsonism, dementia, or both depending on whether the Lewy body pa thology begins in the midbrain, the cortex, or both together. When it begins in the midbrain, diffuse Lewy body disease is indistinguishable initially from idiopathic Parkinson's disease. Diffuse Lewy body dise ase may be a common cause of dementia complicating Parkinson's disease .