Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody-positive dermatomyositis (DM) is characterized by clinically amyopathic DM (CADM) and rapidly progressive interstitial lung disease (RP-ILD), which is correlated with an aggressive course and poor prognosis (1). This evidence concerns the gene IFIH1 and clinically amyopathic dermatomyositis.