Alzheimer's disease: Report of two autopsy cases with a clinical diagnosis of corticobasal degeneration
Article first published online: 22 SEP 2009
© 2009 Japanese Society of Neuropathology
Volume 30, Issue 2, pages 140–148, April 2010
How to Cite
Okazaki, K., Fu, Y.-J., Nishihira, Y., Endo, M., Fukushima, T., Ikeuchi, T., Okamoto, K., Onodera, O., Nishizawa, M. and Takahashi, H. (2010), Alzheimer's disease: Report of two autopsy cases with a clinical diagnosis of corticobasal degeneration. Neuropathology, 30: 140–148. doi: 10.1111/j.1440-1789.2009.01062.x
- Issue published online: 21 MAR 2010
- Article first published online: 22 SEP 2009
- Received 29 July 2009; revised and accepted 3 August 2009.
- Alzheimer's disease;
- cortical syndrome;
- corticobasal degeneration;
Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Corticobasal degeneration (CBD) is a rare neurodegenerative disease affecting adults, being characterized clinically by a combination of extrapyramidal signs and focal cortical syndromes. In both diseases, tau deposits are a characteristic neuropathological feature. We report two new patients with autopsy-proven AD, in whom clinical diagnoses of CBD were made during life. The ages of the patients at onset were 52 and 67 years, and the disease durations were 9 and 15 years, respectively. At autopsy, both cases exhibited marked cortical atrophy with evident neuronal loss in the convex areas of the frontal and parietal lobes. Immunohistochemically, AT8-positive neurofibrillary tangles (NFTs) and Aβ-positive senile plaques (SPs) were widespread and abundant in the cerebral cortex (Alzheimer pathology stage VI/C of Braak and Braak), leading us to the final pathological diagnosis of AD. No tau lesions suggestive of CBD were observed, and the deep gray matter areas, including the substantia nigra, were unremarkable (exceptionally, only mild neuronal loss was noted in the putamen in case 2). These findings further strengthen the idea that in AD, neurodegeneration with tau and Aβ deposits may begin in the fronto-parietal neocortical areas, which are often preferentially affected in CBD, earlier than, or as early as the medial temporal lobe, and that extrapyramidal signs, such as rigidity and tremor, can occur in the absence of neuronal loss in the basal ganglia and substantia nigra.