Department of Clinical Immunology and Rheumatology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, 226014, India.
Rheumatol Int. 2021 Mar;41(3):551-563. doi: 10.1007/s00296-020-04779-y. Epub 2021 Jan 10.
Overlap myositis (OM), an important subset of idiopathic inflammatory myopathies (IIM), is being increasingly recognized with wider myositis-specific autoantibody (MSA) testing. We studied the differences in clinical characteristics and long-term outcomes of OM with Dermatomyositis (DM), Polymyositis (PM), anti-synthetase syndrome (ASSD), and Cancer-associated IIM (CAM). Data from the MyoCite registry (Dec2017-May2020), a prospective dataset of IIM was extracted for the clinical profile, and MSAs, immunosuppressants received, disease activity (relapses and incomplete response), and treatment-related (drugs ADRs and infections) adverse events (DRAE and TRAE) were collected and analyzed between groups. Of 214 adults (58-OM,89-DM,27-ASSD,33-PM,7-CAM), OM had a greater female preponderance (13.5:1). Raynaud's and sclerodactyly were the prime distinguishing features of OM. OM could be distinguished from PM by frequent arthritis (OR-3.2) and infrequent dysphagia (OR-0.17); DM with greater nephritis (OR-20), infrequent dysphagia (OR-0.24) and rashes (OR-0.02); and ASSD by infrequent ILD (OR-0.07), and mechanic's hand (OR-0.05). 50% fulfilled the classification criteria for ASSD in the absence of MSA testing. ANA was positive more often (PM/DM: OR-6.7) and anti-Ro52 (OR-4.5) frequent in OM. Baseline serum creatinine and acute phase reactants were higher. OM received lower glucocorticoids (0 mg/kg, p < 0.001). Overall, 90% and 84% of OM at 12 and 24 months, respectively, achieved remission, with similar DRAE and TRAE as other IIM subsets. OM can be misdiagnosed as ASSD in the absence of MSA testing. Raynaud's, sclerodactyly, and a positive ANA may identify OM and prevent overtreatment.
重叠性肌炎（OM）是特发性炎症性肌病（IIM）的一个重要亚类，随着肌炎特异性自身抗体（MSA）检测范围的扩大，其越来越受到重视。我们研究了 OM 与皮肌炎（DM）、多发性肌炎（PM）、抗合成酶综合征（ASSD）和癌症相关的 IIM（CAM）在临床特征和长期结局方面的差异。从 MyoCite 登记处（2017 年 12 月至 2020 年 5 月）提取了 IIM 的前瞻性数据集，以提取临床特征和 MSA、接受的免疫抑制剂、疾病活动（复发和不完全缓解）以及与治疗相关的（药物不良反应和感染）不良事件（DRAE 和 TRAE），并对组间进行了分析。在 214 名成年人（58 例 OM、89 例 DM、27 例 ASSD、33 例 PM、7 例 CAM）中，OM 女性患者比例更高（13.5:1）。雷诺现象和硬皮病是 OM 的主要鉴别特征。OM 可通过频繁关节炎（OR-3.2）和不频繁吞咽困难（OR-0.17）与 PM 区分；DM 可通过更频繁肾炎（OR-20）、不频繁吞咽困难（OR-0.24）和皮疹（OR-0.02）与 OM 区分；ASSD 可通过不频繁间质性肺病（OR-0.07）和技工手（OR-0.05）与 OM 区分。在未进行 MSA 检测的情况下，有 50%的患者符合 ASSD 的分类标准。OM 中抗核抗体更常见（PM/DM：OR-6.7），抗 Ro52 抗体更常见（OR-4.5）。基线血清肌酐和急性期反应物较高。OM 接受的糖皮质激素剂量较低（0mg/kg，p<0.001）。OM 在 12 个月和 24 个月时分别有 90%和 84%达到缓解，与其他 IIM 亚组相比，DRAE 和 TRAE 相似。在未进行 MSA 检测的情况下，OM 可能被误诊为 ASSD。雷诺现象、硬皮病和抗核抗体阳性可能有助于识别 OM，并防止过度治疗。
