As revealed in univariate analyses, in the anti-MDA5+ DM group, age > 43.5 years, shorter disease course, a decreased number of peripheral T cells, Th cells, Ts cells, NK cells, and lymphocytes, as well as increased levels of KL-6, AST, ALT, NLR, and ESR were significantly associated with PF-ILD. Here, MUC1 is linked to pemphigus foliaceus.