ステロイド・IVIgで筋力回復が不良な皮膚筋炎・壊死性筋症—難治性の皮膚筋炎・壊死性筋症

Treatment of Dermatomyositis and Immune-Mediated Necrotizing Myopathy with Poor Muscle Recovery with Steroids and IVIg: Intractable Dermatomyositis and Immune-Mediated Necrotizing Myopathy

特発性炎症性筋疾患である皮膚筋炎と免疫介在性壊死性筋症は，臨床病理学的特徴が異なり区別される。いずれもステロイド治療が第一選択で，免疫抑制薬や免疫グロブリン大量静注療法が適宜使用される。少数例ながらこれらの治療への抵抗性を示すため，各症例における丹念な四肢・体幹の筋力評価に加えて，全身炎症所見や筋病理所見，骨格筋画像，悪性腫瘍や間質性肺疾患などの合併症を勘案して，治療計画を立てる必要がある。現状では，難治例に対する治療戦略は十分確立しておらず，使用可能な治療薬が限られていることからも，今後の治療法の開発が求められる。

Abstract

Among idiopathic inflammatory myopathies, dermatomyositis and immune-mediated necrotizing myopathy are distinguished by their different clinicopathological features. Corticosteroids are administered as the first-line treatment for both, and immunosuppressive agents and intravenous immunoglobulin important second-line treatments. Since some patients show resistance to these therapies, it is necessary to considering additional treatment based on muscle pathology, muscle imaging, and systemic complications such as malignancy and interstitial lung disease, in addition to the careful evaluation of muscle strength. However, more effective therapeutic strategies are not yet well-established for refractory cases because the available therapeutic agents are limited. Therefore, the development of novel therapies is required in the future.