慢性進行性に経過し著明な筋拘縮を示したミオパチー症例

A CASE OF SLOWLY PROGRESSIVE MYOPATHY WITH PROMINENT MUSCLE CONTRACTURE

I．まえがき

　近年多発性筋炎と進行性筋ジストロフィー症との異同についての論義は多く，Nattrass （'54）^6）が進行性筋ジストロフィー症と診断された症例のなかから，多発性筋炎と考えられるもののあることを指摘したことはあまりにも有名である。

　その後両者の鑑別要点について種々の論拠があげられているが，まだ十分なものとはいえない。ことに慢性経過をとつた症例においては両者間の鑑別がきわめて困難となる。筋生検，筋電図，血清酵素活性など諸検査所見が重要視されつつあるが，それらの評価についてもまだ明確な見解がなく診断の困難な症例に遭遇することがある。発症以来16年の経過を示し，慢性進行性で，筋拘縮の著明にみられたミオパチー症例を経験したので，症例を中心に若干の考察を加えたい。

A female case, 18 years, whose disease had the onset at age of about one year and seven months, has slowly progressed and has shown muscle weakness and strange palpation like sand-bag in the muscles of both extremities, for that there were muscle contracture and flextion position of both limbs, was reported.

The muscle weakness and muscle contract-ure involved all the muscles over the whole body, excluding facial muscles. The muscle contracture brought the joint deformity of the limbs as well as considerable lordosis. In neu-rological examination there were no particu-lar findings but hyporeflexia except for the finding of the muscles as previously mention-ed. In the laboratory examination, transami-nase, aldolase, serum protein and electrolytes were within normal value with one exception of the accentuation of erythrocyte sedimenta-tion rate. Electromyogram showed high amp-litude potential during voluntary contraction instead of low amplitude NMU voltage. The muscle biopsy revealed granular floccular degeneration of the muscle fiber with slight phagocytosis and increase of the fatty tissue at the endomysium.

According to those findings, the following may be considered as a diagnosis : progressi-ve muscular dystrophy, chronic polymyositis, and fibromyositis. However, relationship be-tween them is not clear and must be discussed in detail. The present case is one of giving the accurate diagnosis with difficulty. Actual-ly, it will be reasonable to deal such case with an atypical myopathy.