摘要目的 了解DM患者肌炎特异性抗体(MSAs)谱分布特征及其与临床表现的相关性.方法 收集并整理427例DM患者的血清及临床资料,应用商品化试剂盒检测12种MSAs亚型,并与临床资料进行相关性分析.其中组间差异应用t检验、Mann-Whitney U检验或χ2检验,并进一步建立模型进行MSAs与临床症状之间的Logistic回归分析,明确MSAs亚型是否为临床症状的独立影响因素.结果 427例DM患者MSAs总体阳性率为69.8%,其中抗-ARS、 抗-MDA5及抗-TIF1-γ抗体是最常见的3种MSAs亚型,阳性率分别为19.9%、17.6%及17.1%.χ2分析显示DM患者不同皮疹类型与MSAs亚型相关.Logistic回归分析显示DM患者皮肤肌肉外临床症状与MSAs亚型相关,抗-MDA5[OR=5.266,95%CI(2.522,10.996),P<0.01]和抗-Jo-1[OR=6.232,95%CI(1.674,23.199),P=0.006]抗体阳性的DM患者易出现ILD,而抗-Mi-2[OR=0.208,95%CI(0.074,0.580),P=0.003]和抗-TIF1-γ[OR=0.189,95%CI(0.096,0.370),P<0.01]抗体阳性患者较少出现ILD.抗-TIF1-γ[OR=5.907,95%CI(2.868,12.168),P<0.01]抗体为肿瘤发生的独立危险因素.抗-TIF1-γ[OR=2.789,95%CI(1.594,4.880),P<0.01]、抗-NXP2[OR=2.983,95%CI(1.274,6.982),P=0.012]及抗-SAE1[OR=4.815,95%CI(1.082,21.424),P=0.039]阳性是DM患者发生吞咽障碍的独立危险因素,而抗-MDA5[OR=0.349,95%CI(0.169,0.720),P=0.004]阳性患者较少发生吞咽障碍.结论 DM患者血清中MSAs阳性率高,不同MSAs亚型与DM临床表现相关,可能是该临床表现的独立影响因素,提示MSAs的检测有利于监测DM患者肌肉外临床特征.

abstractsObjective The aim of this study is to analyze the prevalence of myositis-specific autoantibodies (MSAs) and to elucidate their associations with clinical features in Chinese dermatomyositis (DM) patients. Methods Four hundreds and twenty-seven DM patients were enrolled in this retrospective study. Clinical features and sera were collected. Twelve subtypes of MSAs were detected by commercial test kits. The correlations between MSAs and clinical phenotypes in DM patients were calculated by t test, Mann-Whitney U test or χ2 test. In order to clarify whether MSAs subsets would be independent factors of certain clinical feature or not, separate models were established to test the correlation via the Logistic regression analysis. Results The positivity of MSAs was 69.8% in 427 patients with DM. Anti-ARS, anti-MDA5 and anti-TIF1-γ antibodies were the three most common MSAs in the DM patients with positivity of 19.9%, 17.6%and 17.1% respectively. Different kinds of rash associated with MSAs subtypes by χ2 test. Certain MSAs subtype might be an independent factor for clinical features via logistic regression analysis. Interstitial lung disease (ILD) was observed more frequently in patients carrying anti-MDA5 [OR=5.266, 95%CI (2.522, 10.996), P<0.01] and anti-Jo-1 [OR=6.232, 95%CI (1.674, 23.199), P=0.006]. On the contrary, anti-Mi2 [OR=0.208, 95%CI (0.074, 0.580, P=0.003] and anti-TIF1-γ [OR=0.189, 95%CI (0.096, 0.370), P<0.01] were protective factors against developing ILD. Anti-TIF1-γ was an independent risk factor for cancer-associated myositis [OR=5.907, 95%CI (2.868, 12.168), P<0.01]. Anti-TIF1-γ[OR=2.789, 95%CI (1.594, 4.880) P<0.01], anti-NXP2 [OR=2.983, 95%CI (1.274, 6.982), P=0.012] and anti-SAE1 [OR=4.815, 95%CI (1.082, 21.424), P=0.039] could worsen dysphagic tendencies. In contrast, anti-MDA5 [OR=0.349, 95%CI (0.169, 0.720), P=0.004] might decrease the prevalence of this manifestation. Conclusion Patients with DM have a high frequency of MSAs. Some subtypes of MSAs are correlated with and may be independent factors of different clinical phenotypes. These indicated that MSAs can be useful biomarkers in monitoring the extramuscular features in DM patients.