先天性魚鱗癬様紅皮症（Epidermolytic Hyperkeratosis）の発症病理について—その電顕的検索

ELECTRONMICROSCOPIC STUDIES ON PATHOGENESIS OF EPIDERMOLYTIC HYPERKERATOSIS

はじめに

　先天性魚鱗癬様紅皮症は1902年のBrocqの報告以来報告例は決して稀ではない。その後魚鱗癬を主徴とする疾患の種類は漸次累積されて現在ではその主要なものが十種を越えている状態である。さらに最近の遺伝学の進歩はGene分析に肉迫し，分子生物学的な遺伝子の面とその伝達形式から疾患の分類配列の再編成をうながしている。近刊のRook, Wilkinson and Eblingの教本^1），Jaddasohnの叢書のSchneyder und Klunkerの綜説^2），Butterworth and Streanの著書^3）などがそれである。しかし各々の本症に対する取り扱い方はまちまちであり，なお多くの疑念を抱かしめるのが現状であろう。

　一方，病理発生についてはVan Scott一派^4）5）6）は本症をEpidermolytic Hyperkeratosisとし，原因的にはLamellar Ichthyosisと同様と述べ，本症をして現象論的でなく病因論的に改めて見直さんとしている。

Erythrodermia ichthyosiformis congenita is regarded as a benign form or variant of ichthyosis congenita. Van Scott et al. thought that histogenesis of this disease was accelerated turnover time of keratinocyte system, that is shortened life span of the system. They regarded the name of epidermolytic hyperkeratosis as a proper one.

A 14-year-old boy of this disease was reported. Paternal grandparents were cousins, and the same disorder could not be proved in his family. At the age of one month, miliaria-like eruption was found on the face and then it was generalized over the entire body surface. At the same time his skin became rough and covered with waxy scales. At the age of one year, bullae were formed on the flexor surfaces of the joints. These manifestations showed slight tendency to remission after two years of age. Histologic picture was typical. There was hyperkeratosis, and cells of granular layer were swollen and degenerated. Keratohyalin granules were conglomerated. Malpighian cells showed retiform degeneration.

Electronmicroscopic picture of basal cells showed increased number of mitochondria, ribosomes and tonofilaments, which suggested increased and abnormal activity of the cells. In the squamous cells marked increase of tonofilaments, appearance of Odland bodies in the deep layer of the epidermis, increased number of ribosomes were observed. In the granular layer, huge keratohyalin granules and markedly increased number of tonofilaments were proved. Normal keratin pattern could not be seen.

These findings seemed to support Van Scott's opinion.