Idiopathic inflammatory myopathy was misdiagnosed as dermatosis(6/16),lung diseases(5/16),abnormal hepatic function(2/16),rheumatic fever(2/16),and arrhythmia(1/16).

• 误诊疾病包括敏感性皮炎、药物疹、荨麻疹等皮肤疾病共6例(6/16),肺部病变5例(5/16),肝功能异常2例(2/16),风湿热2例(2/16),心律失常1例(1/16)。误诊病例的最后确诊时间从半月至6月不等。