[Skin Manifestations in Dermatomyositis and Antisynthetase Syndrome]

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.