Huppertz H I, Kaiser W A
Children's University Hospital, Würzburg, Germany.
Rheumatol Int. 1994;14(3):127-9. doi: 10.1007/BF00300815.
Demonstration of myositis in juvenile dermatomyositis (JDM) has traditionally required the presence of two out of three objective findings including muscle enzyme studies, electromyography, and muscle biopsy. Magnetic resonance imaging (MRI) is considered another objective criterion and has been recommended for follow-up studies as well. We report on a 6-year-old girl with JDM, presenting with facial rash and proximal muscle weakness, in whom MRI, in conjunction with elevated creatinine kinase (CK) levels, was diagnostic, with an increased T2 signal of proximal muscles. MRI reflected exacerbation of myositis in spite of steroid therapy 2 weeks later, but failed to mirror normalization of muscle strength and CK values 10 weeks later. In fact, improvement of MRI followed clinical and laboratory normalization with a delay of 2 months. This possible delay should be considered when MRI is used to monitor the response to therapy.
传统上，幼年皮肌炎（JDM）中肌炎的确诊需要三项客观检查结果中的两项，包括肌酶检查、肌电图和肌肉活检。磁共振成像（MRI）被视为另一项客观标准，也被推荐用于随访研究。我们报告了一名6岁患JDM的女孩，她出现面部皮疹和近端肌无力，在该病例中，MRI结合肌酸激酶（CK）水平升高具有诊断意义，近端肌肉T2信号增强。尽管2周后进行了类固醇治疗，但MRI仍显示肌炎加重，而10周后未能反映出肌力和CK值的正常化。事实上，MRI的改善在临床和实验室指标正常化之后出现，延迟了2个月。在使用MRI监测治疗反应时应考虑到这种可能的延迟。
