特发性炎症性肌病是一组罕见的以肌肉炎症病变为特征的自身免疫性疾病。儿童期最常见类型是皮肌炎。虽然已有多个诊断标准被提出,但皮肌炎的诊断仍是基于特征性临床表现和实验室辅助检查的临床综合诊断。典型临床表现为亚急性起病,对称性近端为主的肌无力和特征性皮疹。肌活检示肌束膜和小血管周围为主的炎症细胞浸润,以及肌束周为主的肌纤维萎缩。肌肉磁共振、肌肉特异性抗体检测和甲褶镜检查可辅助支持诊断。 Idiopathic inflammatory myopathy is a rare group of autoimmune diseases characterized by muscle inflammation. The most common type of childhood is dermatomyositis. Although several diagnostic criteria have been proposed, the diagnosis of dermatomyositis is still based on clinical features and clinical laboratory tests of laboratory diagnosis. The typical clinical manifestations of subacute onset, symmetry proximal weakness and characteristic rash. Muscle biopsy showed perivascular membrane and small blood vessels around the inflammatory cell infiltration, and muscle bundle week-based muscle fiber atrophy. Muscle MRI, muscle-specific antibody tests, and pleatoscopy help support diagnosis.