HAMの発見とその概説

On the discovery of a new clinical entity: Human T-cell lymphotropic virus Type I-associated Myelopathy (HAM).

　緒言

　最近，われわれはこれまで当教室で経験した一群の特徴あるミエロパチーが，レトロウイルスの一つであるHTLV-I（human T-cell lymphotropic virus type I）が関与した一つの新しい疾患概念として包括されるものであることを提唱し，HTLV-I-associated myelopathy（略称HAM）の名称で報告した^1〜5）。本論文では，HAM発見の経過を紹介し，ひきつづき現在までに追加された事項を含めHAMについて概説する。

The history of HTLV-I-associated myelopathy (HAM) dates back 15 years ago when one of us (Professor Igata) started his new department in Kagoshima Prefecture, whereupon he pointed out some peculiarities of spinal spastic paraplegia (SSP) cases in this locale. Specifically, not only was the incidence high but also that cases tended to have clusters of characteristic neurologic features. These signs and symptoms were: slowly progressive clinical course, prominent pyramidal tract signs and mild sensory and sphincteric disturbances. In 1975, one of us (M. Osame) showed through an epidemiologic study in the same locale, that of the 1,700,000 population, 55 cases were SSP compared to the 29 Duchenne Dystrophy cases. Retrospetive study of the sporadic SSP cases revealed that majority of them were in fact HAM.