小児重症筋無力症の症状と治療成績

Clinical features and therapeutic outcome of childhood myasthenia gravis

要約　目的：小児重症筋無力症の眼科的な臨床症状と治療成績の報告。対象と方法：過去21年間に小児重症筋無力症として当センター小児神経科から紹介された18例を対象とした。男児11例，女児7例で，12例は眼筋病変のみで，6例が眼病変を伴う全身型であった。受診時の年齢は0～12歳で，14例が3歳未満であった。2か月～7年までの経過を追跡した。結果：全18例中17例に眼瞼下垂があった。11例に斜視があり，うち10例は外斜視であった。全身型6例中4例で抗アセチルコリン抗体が陽性であった。眼筋型には副腎皮質ステロイドの全身投与が奏効したが，全身型では他の免疫抑制薬を必要とした。再燃までの期間は，眼筋型よりも全身型が短かった。眼病変に対し外科治療を必要とする症例はなかった。結論：小児重症筋無力症の眼症状は，全例が内科的治療で改善した。

Abstract.　Purpose：To report clinical manifestations and therapeutic outcome of childhood myasthenia gravis. Cases and Method：This retrospective study was made on 18 cases of childhood myasthenia gravis who were referred to us from the Department of Childhood Neurology of our institution during the past 21 years. The series comprised 11 males and 7 females. The age ranged from 0 to 12 years. Fourteen cases were aged less than 3 years. Extraocular muscles, including the levator, were only affected in 12 cases. Six cases had both systemic and ocular lesions. Cases were followed up for 2 months to 7 years. Results：Blepharoptosis was present in 17 out of 18 cases. Strabismus was present in 11 cases, of which 10 cases had exotropia. Anti-acetylcholine antibody was positive in 4 out of 6 cases of generalized type. Systemic corticosteroid was effective for cases of ocular affection only. Cases of generalized type needed additional immunosuppressive agents. Recurrences appeared earlier in cases of generalized than ocular type. No case needed surgical intervention. Conclusion：Systemic medication was effective for ocular manifestations of myasthenia gravis in the present series.