IFIH1 and clinically amyopathic dermatomyositis: Anti‐melanoma differentiation‐associated gene 5 (MDA5)‐antibody‐positive clinically amyopathic dermatomyositis (CADM) is a special subclass of dermatomyositis (DM) characterized by typical skin lesions of DM without or with only mild muscle involvement and a very high mortality rate due to rapidly progressive interstitial lung disease (RPILD) [1, 2].