摘要目的:分析抗黑素瘤分化相关基因（MDA）5 抗体阳性皮肌炎相关间质性肺疾病患者（MDA5 +DM-ILD）的临床特征和预后因素。 方法:收集2017年1月至2021年3月在南京鼓楼医院呼吸科住院的MDA5 +DM-ILD患者的临床资料及生存信息。分别比较生存组与死亡组、快速进展与非快速进展性间质性肺疾病（RP-ILD）患者的临床数据，并进行组间对比分析。 结果:纳入抗MDA5 +DM-ILD患者105例（中位发病年龄54岁），其中61例为女性（61/105，58%）。皮肌炎主要类型为无肌病性皮肌炎（74/105，70%），其次为皮肌炎（31/105，30%）。肺外主要临床表现为皮肤病变（60/105，57.1%）、肌肉表现（20/105，19%）、关节痛及关节炎（20/105，19%）。15.4%患者抗核抗体（antinuclear antibody，ANA）阳性，抗体滴度≥1∶320；61.9%患者的抗RO-52 kDa抗体阳性。随访期间66例（66/105，62.8%）患者发生RP-ILD，58例（58/105，56.3%）死亡。氧合指数低（ OR=0.974，95% CI：0.954~0.994， P=0.012）及无关节疼痛表现（ OR=0.032，95% CI：0.002~0.663， P=0.026）是RP-ILD的独立危险因素。Cox回归分析显示，RP-ILD（ HR=3.194，95% CI：1.025~9.954， P=0.045）、年龄>53岁（ HR=3.450，95% CI：1.388~8.577， P=0.008）、铁蛋白水平>1 330.5 μg/L（ HR=3.032，95% CI：1.208~7.610， P=0.018）和C反应蛋白>16.95 mg/L（ HR=2.794，95% CI：1.102~7.084， P=0.030）是死亡的独立预测因子。 结论:呼吸科就诊的抗MDA5 +DM-ILD患者，临床表现呈现异质性，多数为无肌病性皮肌炎，RP-ILD发生率高，死亡风险大。对基线自身抗体筛查阴性，抗RO52kDa抗体阳性的快速进展性ILD患者，即使无相关皮疹、关节、肌肉表现，应考虑抗MDA5抗体筛查。

abstractsObjective:To analyze the clinical characteristics and prognostic factors of patients with anti-melanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis associated interstitial lung disease (DM-ILD).Methods:The patients with MDA5 +DM-ILD who were admitted to Department of Respiratory Medicine, Nanjing Drum Tower Hospital from January 2017 to March 2021 were enrolled. The clinical data and survival information were analyzed retrospectively. Patients were divided into survival group or death group, and rapid progressive ILD (RP-ILD) group or non-rapid progressive ILD group, according to their survival status and clinical progression. Results:A total of 105 patients with anti-MDA5 +DM-ILD (median age of onset 54 years) were enrolled, 58% being female (61 cases). The main sub-type of dermatomyositis was amyopathic dermatomyositis ( n=74, 70%), followed by dermatomyositis ( n=31, 30%). The main extrapulmonary manifestations were skin lesions ( n=60, 57.1%), muscle manifestations( n=20, 19%) and arthralgia /arthritis ( n=20, 19%). 15.4% of the patients had positive ANA (antibody titer≥1∶320), and 61.9% of the patients had anti-RO-52 kDa antibody. A total of 66 patients (62.8%) developed RP-ILD, and 58 patients (56.3%) died. Lower oxygenation index ( OR=0.974, 95% CI:0.954-0.994, P=0.012) and no joint pain ( OR=0.032, 95% CI: 0.002-0.663 P=0.026) were independent risk factors for RP-ILD. Cox regression analysis showed that RP-ILD ( HR=3.194, 95% CI:1.025-9.954, P=0.045), older than 53 years ( HR=3.450, 95% CI: 1.388-8.577, P=0.008), ferritin level more than 1 330.5 ng/ml ( HR=3.032, 95% CI 1.208-7.610, P=0.018) and C-reactive protein (CRP) above 16.95 mg/L ( HR=2.794, 95% CI:1.102-7.084, P=0.030) were independent predictors of mortality. Conclusions:The clinical manifestations of patients with anti-MDA5+DM-ILD presenting to the respiratory department were heterogeneous, with most being amyopathic dermatomyositis, and both the incidence of RP-ILD and the risk of death were high. Even in the absence of associated rash, joint, or muscle manifestations, anti-MDA5 antibody screening should be considered in patients with rapidly progressive ILD who were negative on baseline autoantibody screening but positive for anti-RO52kDa antibody.