Department of Neurology, Osaka University Graduate School of Medicine, Japan.
Intern Med. 2020 Sep 1;59(17):2173-2176. doi: 10.2169/internalmedicine.4601-20. Epub 2020 May 26.
We herein report a 56-year-old Japanese woman who had been diagnosed with hereditary angioedema. She experienced progressing muscle weakness and pain in the upper and lower extremities. Blood tests revealed a marked increase in creatine kinase levels; however, myositis-specific autoantibodies were not detected. Serum C1-inhibitor activity and C4 levels were low. A muscle biopsy showed mild muscle fiber necrosis and C5b-9 deposition in the endomysial capillary vessel walls and sarcolemma, mimicking necrotizing myopathy. These results suggest that C1-inhibitor deficiency induces myositis-like symptoms through the activation of the complement pathway and deposition of the membrane attack complex in the muscles.
我们在此报告一例 56 岁的日本女性遗传性血管性水肿患者，其出现进行性四肢肌肉无力和疼痛。血液检查显示肌酸激酶水平显著升高；然而，并未检测到肌炎特异性自身抗体。血清 C1 抑制剂活性和 C4 水平降低。肌肉活检显示轻微的肌纤维坏死和肌内膜毛细血管壁和肌膜的 C5b-9 沉积，类似于坏死性肌病。这些结果表明，C1 抑制剂缺乏通过补体途径的激活和膜攻击复合物在肌肉中的沉积引起类似肌炎的症状。
