Anti-Mi-2 antibody is most strongly associated with which feature in dermatomyositis?

• A. Anti-Mi-2
• B. Anti-SRP
• C. Anti-HMG CoA reductase
• D. Anti-cytoplasmic 5'-nucleotidase

Answer: (A)

Autoantibodies in dermatomyositis help define distinct clinical patterns. Anti-Mi-2 is the antibody most closely linked to the classic dermatomyositis skin findings—heliotrope rash around the eyes and Gottron papules on the hands. Patients with this antibody typically have prominent cutaneous disease and tend to respond well to therapy, with a relatively favorable prognosis. It is not strongly associated with interstitial lung disease or cancer risk, unlike some other myositis-associated antibodies. For contrast, anti-SRP is more often linked to a necrotizing, rapidly progressive muscle weakness; anti-HMG-CoA reductase is associated with statin-related autoimmune myopathy; and anti-cytoplasmic 5'-nucleotidase (NT5C1A) is more linked to inclusion body myositis.