IFIH1 and myositis disease: We presented four cases where NVC contributed to the diagnosis of myositis: a patient with anti-MDA5 DM and another with anti-SAE1 DM who initially presented with rashes, a patient with anti-Mi2 DM that mimicked IMNM clinically and pathologically, and a patient with seronegative scleromyositis that mimicked IBM clinically (Figure 5).