意义未明的单克隆丙种球蛋白病伴炎性肌病1例（附文献复习）

目的：报告1例54岁男性意义未明的单克隆丙种球蛋白病（MGUS）伴炎性肌病的患者。方法：回顾分析我院收治的1例MGUS伴炎性肌病患者的临床表现，肌肉病理改变和治疗，并结合复习国外文献报道的9例病例。结果：患者于52岁时出现不对称性双上肢远端无力，并逐渐加重。血清免疫电泳检查示IgM单株峰，且单克隆球蛋白（M-蛋白）浓度低于30g·L^-1，骨髓中浆细胞〈10％，尿蛋白（-），肾功能正常，无贫血、高钙血症及溶骨性改变。肌活检提示炎性肌病可能。予丙种球蛋白、环磷酰胺、双膜法血浆置换治疗后症状短期有所改善，但总体仍不断进展。结论：MGUS可合并炎性肌病，可能与M-蛋白介导的自身免疫相关。

Myositis with Monoclonal Gammopathy of Undetermined Significance:A Case Report (Literature Review)

Aim： A 54 year-old man who had myositis with monoclonal gammopathy of undetermined significance（MGUS） was described. Methods： A case diagnosed as myositis with MGUS was reported and 9 published cases were reviewed. Results： The patient developed asymmetrical muscle weakness in his upper limbs at 52. An IgM spike was identified on serum electrophoresis, and serum M-protein value was less than 30 g·L^-1. Fewer than 10% plasma cells were found in the bone marrow. No signs of proteinuria, anemia, hypercalcemia, renal failure or bone lesions were noted. The muscle biopsy revealed myositic changes. He responded to IVIG, CTX and DFPP temporarily, but the weakness still progressed. Conclusion： Myositis with gammopathy may be more than a chance association, and serum M-protein seems to be responsible for the myositis.