Anti-NXP-2 antibodies are present in 1.6-30% of adult DM and 18-25% of JDM. In JDM they are associated with cutaneous calcinosis cutis. In adult DM they are significantly associated with the presence of cancer (cancer was found in 13.6% of Anti-NXP-2 positive DM patients). Anti-MDA5 antibodies are present in 7-35% of adult DM. Features consist of absent or mild muscle symptoms (CADM); associated with rapidly progressive ILD; specific mucocutaneous features of skin ulcerations and papules; higher risk of oral ulcerations and arthritis.