2012年,大量肌炎病例使用抗线粒体M2(AMA-M2)抗体,众所周知,这是原发性胆汁性胆管炎(PBC)的血清学标志,在日本报道。最近,一些来自日本的案例系列,法国,美国,中国和印度已经表明,大约2.5%至19.5%的患有肌炎的患者具有AMA-M2抗体。这项研究的目的是澄清患病率,临床特征,治疗结果,和AMA-M2阳性肌炎的严重程度决定因素。
本研究为多中心观察性研究。我们招募了在2012年至2021年的十年期间被诊断为肌炎的患者。
在总共185例炎症性肌病患者中,17例患者AMA-M2抗体阳性。典型症状为肌无力,主要累及椎旁肌,减肥,呼吸衰竭,和心脏并发症。17例患者中有13例出现心脏并发症。发现呼吸衰竭与改良Rankin量表(mRS)评分之间存在很强的相关性。呼吸衰竭和体重之间也有很强的相关性,表明体重减轻可能是呼吸衰竭潜在进展的指标。17例患者中有6例并发恶性肿瘤。
这项研究表明,肺活量%(VC)、体重指数(BMI),AMA-M2阳性肌炎患者的mRS评分。免疫治疗常改善CK水平和呼吸功能障碍。因此,我们建议应监测%VC和BMI作为治疗AMA-M2阳性肌炎的疾病指标。
In 2012, a large number of myositis cases with anti-mitochondrial M2 (AMA-M2) antibody, which had well been known as the serological hallmark for primary biliary cholangitis (PBC), were reported in Japan. Recently, some case series from Japan, France, America, China and India have shown that approximately 2.5% to 19.5% of patients with myositis have AMA-M2 antibody. The objective of this study was to clarify the prevalence, clinical features, treatment outcome, and severity determinants of AMA-M2 positive myositis.
This study was a multicenter observational study. We enrolled patients who were diagnosed with myositis during a ten-year period between 2012 and 2021.
Of the total of 185 patients with inflammatory myopathy, 17 patients were positive for AMA-M2 antibody. The typical symptoms were weakness mainly involving paravertebral muscles, weight loss, respiratory failure, and cardiac complications. Thirteen of the 17 patients had cardiac complications. A strong correlation was found between respiratory failure and modified Rankin Scale (mRS) score. A strong correlation was also found between respiratory failure and body weight, indicating that weight loss can be an indicator of potential progression of respiratory failure. Six of the 17 patients were complicated by malignancy.
This study showed significant correlations between % vital capacity (VC), body mass index (BMI), and mRS score in patients with AMA-M2-positive myositis. Immunotherapy often improved CK level and respiratory dysfunction. We therefore propose that %VC and BMI should be monitored as disease indicators in treatment of AMA-M2-positive myositis.