IFIH1 and dermatomyositis: Anti-MDA5+ dermatomyositis (anti-MDA5+ DM), a distinct subtype of DM, is characterized by serum reactivity against the autoantigen MDA5 and unique cutaneous manifestations such as Gottron’s papules and heliotrope rash, often with absent or atypical myositis symptoms (1, 7, 8).