PIK3C2A and dermatomyositis: CBC: complete blood count; APR: acute phase reactants; HM: hematologic malignancies; HIV: human immunodeficiency virus; DM: dermatomyositis; CPK: creatine phosphokinase; AST: aspartate aminotransferase; ALT: alanine aminotransferase; LDH: lactate dehydrogenase; DIF: direct immunofluorescence; MDS: myelodysplastic syndrome.