[An autopsied case of atypical presenile dementia which shows lobar atrophy, severe neurofibrillary tangles and calcification].
We report an autopsy case of atypical presenile dementia. Shibayama, Kosaka and others had reported similar autopsy cases. These cases had the following common pathologic characteristics: circumscribed cerebral atrophy, diffuse neurofibrillary tangles (NFTs) noted in the cerebral cortex with few senile plaques (SPs), and pathological calcification. We propose the term "dementia with cerebral calcification and tangles" (DCCT) for this atypical presenile dementia. Our patient, who was female and died at the age of 65 years, also exhibited these characteristics. Her clinical diagnosis was Alzheimer's disease. She had developed apparent dementia at the age of 55. Psychological and neurological symptoms such as memory impairment, speech disturbance and abnormal behavior slowly progressed. Gradually, she had become bedridden in her own home. When she was 65 years old, she was admitted because of pneumonia, and died soon after. In the pathologic examination of our patient, the brain weight was 850 g, and severe cerebral atrophy predominant in the temporal lobe was noted. Microscopically, diffuse and numerous NFTs were also found in the cerebral cortex and brain stem. Some NFTs were observed in the dentate nucleus of the cerebellum. However, SPs were seldom noted. Calcifications were also found in the putamen, globus pallidus and cerebellar cortex. NFTs in our case had developed without the formation of SPs. The degree of the NFT formation was correlated to the extent of cerebral cortical atrophy and neuron loss. Therefore, we suspect that NFTs with neuron loss strongly contribute to clinical symptoms such as dementia. The distribution of NFTs resembles that in patients with Alzheimer's disease, they are more prominent in the temporal lobe in our case. Although there has not been any discussion about the findings of glial cells and neuropils in DCCT, our detailed examination showed argyrophilic structures in glial cells and in neuropils. Most of the glial cells appeared to be oligodendrocytes. Calcification is also a prominent characteristic of DCCT. Using analytical electron microscopy, we examined the area of calcification in the globus pallidus and cerebellum, and found an accumulation of both Fe and Ca. The role of calcification in the pathogenesis, however, remains unclear. It is very important to examine cases of atypical presenile dementia clinicopathologically, in order to study the correlation between NFTs and SPs in neurological disease, and to understand their pathogenetic significance.