[Familial parkinsonism and dementia with ballooned neurons, argyrophilic neuronal inclusions, atypical neurofibrillary tangles, tau-negative astrocytic fibrillary tangles, and Lewy bodies].

We reported a new type of familial Parkinson's disease (familial PD) previously. After that, we examined this family by both the immunohistochemical staining using anti-alpha-synuclein antibody and the analysis of alpha-synuclein gene. We reported these results, and briefly reviewed both familial PD and "familial frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17)". Immunohistochemical staining with anti-alpha-synuclein antibody revealed that the argyrophilic neuronal inclusions and atypical barely tau-positive neurofibrillary tangles were strongly immunoreactive, whereas the ballooned neurons and astrocytic fibrillary tangles were unreactive. DNA analysis of the leukocytes obtained from one live patient of our family did not show any mutations in the entire exons of alpha-synuclein gene. Our results indicated that our family had familial diffuse Lewy body disease with atypical features and without alpha-synuclein gene abnormalities. Features of familial PD included 1) autosomal dominant inheritance, 2) not uncommon atypical clinical features, 3) variable symptomatology and dopa-responsiveness, and 4) low incidence of alpha-synuclein gene abnormalities. Our familial PD showed similar features, and neuropathological findings of our patients also resembled FTPD-17 in the presence of frequent ballooned neurons and neurofibrillary tangles in the cerebral cortex, but were different in the presence of Lewy bodies and paucity of tau pathology.