Division of Pulmonary, Critical Care and Sleep Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, 593 Eddy Street, POB 224, Providence, RI, 02903, USA.
Department of Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI, USA.
BMC Pulm Med. 2021 Nov 14;21(1):370. doi: 10.1186/s12890-021-01737-7.
Many patients with polymyositis (PM) or dermatomyositis (DM) have circulating myositis-specific antibodies (MSAs). Interstitial lung disease (ILD) is a common manifestation of PM/DM, and it can even precede the onset of characteristic muscle or skin manifestations. Furthermore, there appear to be some patients with ILD and circulating MSAs who do not develop muscle or skin disease even after prolonged follow-up. We sought to determine whether ILD is equally or more common than myositis or dermatitis at the time of initial detection of MSAs.
We identified all patients found to have circulating MSAs at our institution over a 4-year period and assessed for the presence of lung, muscle, and skin disease at the time of initial detection of MSAs. Among those found to have ILD, we compared demographic and clinical features, chest CT scan findings, and outcomes between those with PM/DM-associated ILD and those with ILD but no muscle or skin disease.
A total of 3078 patients were tested for MSAs, and of these 40 were positive. Nine different MSAs were detected, with anti-histidyl tRNA synthetase (anti-Jo-1) being the most common (35% of MSAs). Among patients with positive MSAs, 86% were found to have ILD, compared to 39% and 28% with muscle and skin involvement, respectively (p < 0.001). Fifty percent of all MSA-positive patients had isolated ILD, with no evidence of muscle or skin disease. Those with isolated ILD were more likely to be older and have fibrotic changes on chest CT, less likely to receive immunomodulatory therapy, and had worse overall survival.
In this study we found that individuals with circulating MSAs were more likely to have ILD than classic muscle or skin manifestations of PM/DM at the time of initial detection of MSAs. Our findings suggest that the presence of ILD should be considered a disease-defining manifestation in the presence of MSAs and incorporated into classification criteria for PM/DM.
许多多发性肌炎（PM）或皮肌炎（DM）患者存在循环肌炎特异性抗体（MSA）。间质性肺疾病（ILD）是 PM/DM 的常见表现，甚至可能先于特征性肌肉或皮肤表现出现。此外，似乎有一些患有ILD 和循环 MSA 的患者，即使在长期随访后也不会发展为肌肉或皮肤疾病。我们试图确定在最初检测到 MSA 时，ILD 是否与肌炎或皮炎同样常见，或者更常见。
我们确定了在我们机构在 4 年期间发现的所有存在循环 MSA 的患者，并评估了在最初检测到 MSA 时肺部、肌肉和皮肤疾病的存在情况。在发现ILD 的患者中，我们比较了 PM/DM 相关ILD 患者和ILD 但无肌肉或皮肤疾病患者的人口统计学和临床特征、胸部 CT 扫描结果和结局。
共对 3078 例患者进行了 MSA 检测，其中 40 例为阳性。检测到 9 种不同的 MSA，其中抗组氨酰-tRNA 合成酶（抗-Jo-1）最为常见（35%的 MSA）。在 MSA 阳性患者中，86%的患者存在ILD，而肌肉和皮肤受累的患者分别为 39%和 28%（p<0.001）。所有 MSA 阳性患者中，有 50%为单纯ILD，无肌肉或皮肤疾病证据。单纯ILD 的患者更可能年龄较大，胸部 CT 有纤维化改变，接受免疫调节治疗的可能性较小，总体生存率较差。
在这项研究中，我们发现，在最初检测到 MSA 时，存在循环 MSA 的个体更有可能出现ILD，而不是 PM/DM 的典型肌肉或皮肤表现。我们的发现表明，在存在 MSA 的情况下，ILD 的存在应被视为一种疾病定义性表现，并纳入 PM/DM 的分类标准。
