The idiopathic inflammatory myopathies (IIM) encompass eight categories: 1) dermatomyositis (DM) in adults, 2) juvenile dermatomyositis, 3) amyopathic DM, 4) cancer-associated DM, 5) polymyositis, 6) immune-mediated necrotizing myopathy, 7) inclusion body myositis, and 8) overlap myositis.1 These categories help classify the myopathies based on clinical and histologic features. The incidence of IIM is estimated at…
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