炎症性筋疾患の皮膚病変—皮膚所見からどこまでわかるか

Skin Manifestations in Dermatomyositis and Antisynthetase Syndrome

皮膚病変を呈する炎症性筋疾患は，皮膚筋炎と抗ARS抗体症候群である。これらの疾患では，多くの例で皮膚症状が初発症状となることもあり，皮膚病変の評価は診断において重要な意味を持つ。皮膚病変は，部位と性状の2つの軸から考えるとわかりやすい。手や顔面などの好発部位を系統的に観察しながら，その皮疹の性状を判断していくべきである。特異抗体ごとに特徴的な皮膚症状があることも最近わかってきた。

Abstract

Dermatomyositis and antisynthetase syndrome are among idiopathic inflammatory myopathies (myositis) that have skin lesions. In these disorders, skin symptoms often appear as the initial manifestations, and thus, their evaluation is critical for diagnosis. Two components, “site” and “properties,” are important for understanding the skin manifestations in myositis. The rash in these disorders is induced by Koebner's phenomenon, and is most frequently observed on the hands and face. Recent studies have shown that myositis-specific autoantibodies are useful tools for the diagnosis and classification of these diseases, as they are closely correlated with the clinical and histopathological phenotypes of myositis. It has recently become clear that each antibody is associated with characteristic skin manifestations, especially related to the properties of the skin lesions.