IFIH1 and Skin ulcer: Indeed, previous studies have identified extrapulmonary findings as prognostic factors for PM/DM-ILD, such as old age [4], skin ulcer, ILD with low serum creatine kinase (CK) [5], non-Caucasian race, male sex [6], and seropositivity for anti-melanoma differentiation-associated protein 5 (MDA5) antibody (Ab) [7, 8].