老人斑様変化を示す初老期痴呆の1剖検例

An Autopsy Case of Presenile Dementia with Senile plaque-like Changes

I．緒言

　初老期に痴呆をきたす脳変性疾患のうち，Alzheimer病，Pick病，Creutzfeldt-Jakob病は臨床病理的に病型として一般に承認されているが，これらの非定型例や分類困難な例については未解決の問題が多い。

　Alzheimer病は40〜50歳代に発病し，急速に進行する痴呆があり，臨床的にも特徴的な症状をもち，組織学的にいわゆる老人性変化が老年痴呆に比較して量的に多いことをもつて診断される^1）2）4）。しかし，老人性変化は生理的老年者にも出現するものであり，逆に老年痴呆でもこれを欠く例もある。一方Alzheimer病では老人性変化が本質的なものと考えられるが，老人斑を欠く例，原線維変化を欠く例あるいは両者とも欠く例の報告もある^5）。また若年発病型や痙性麻痺などの神経症状を伴う非定型例の報告もかなりあり^4），Alzheimer病とすることに異論のある例が多い^2）。

The patient is a 46-year-old male. He began to show the disturbance of memory and disori-entation around the age of 39. Delusion of gra-ndeur and motor unrest became remarkable as dementia progressed gradually.

Pathoanatomically no brain atrophy was reco-gnized, but numerous senile plaque-like structu-res were observed in the cerebral cortex and the cerebellar molecular layer, while rarely in cauda-te nucleus, amygdaloid nucleus et al.

These structures in the cerebellar molecular layer resembled "Drusige Entartung" of Scholz and those of the cerebral cortex were reminiscent of senile plaque. However they have no core and show finely fibrillary structures. Histochemical findings of this structure were similar to those of the ground substance itself but the former reacted in an aggravated manner. Otherwise, histologically no neurofibrillary changes of Alz-heimer and granuro-vacuolar degeneration could be obsereved. The cytoarchitecture of the cortex remained intact and degeneration of nerve cells was very slight.

We compared these findings with those of Alzheimer's disease. This case with unusual pla-que-like structures is difficult to classificate, which seems to be different from the atypical Alzheimer's disease.