背景:开发一种基于炎症相关免疫组织化学标记的算法,该算法对特发性炎性肌病(IIM)的诊断能力高于IIM相关组织病理学特征。
方法:对符合2017年EULAR/ACR标准的129例IIM患者的肌肉活检组织和73例非炎症性肌病患者或健康肌肉标本的对照组织进行组织学特征和CD3,CD4,CD8,CD20,CD68,CD163,MX1,MHCI类,MHCII类,和HLA-DR.根据分类和回归树(CART)分析的结果开发了IIM的诊断算法,其中使用免疫染色结果作为预测变量对患有IIM的患者进行分类。
结果:在分析集中(IIM,n=129;控制,n=73),IIM相关组织病理学特征对IIM的诊断准确率为87.6%(敏感性80.6%;特异性100.0%)。CD163的肌肉表达(99.2%vs.20.8%,p<0.001)和MHCI类(87.6%vs.23.1%,p<0.001)在IIM组中明显高于对照组。根据CART分析结果,我们开发了一种结合CD163和MHCI类表达的算法,其诊断准确率为95.5%(敏感性96.1%;特异性94.5%).此外,在94.1%(16/17)不符合2017年EUALR/ACR标准但被专家医师诊断为患有IIM的患者中,我们的算法能够正确诊断IIM.
结论:CD163和MHCI类肌肉表达的组合可能有助于诊断IIM。
BACKGROUND: To develop an inflammation-related immunohistochemistry marker-based algorithm that confers higher diagnostic ability for idiopathic inflammatory myopathies (IIMs) than IIM-related histopathologic features.
METHODS: Muscle biopsy tissues from 129 IIM patients who met the 2017 EULAR/ACR criteria and 73 control tissues from patients with non-inflammatory myopathies or healthy muscle specimens were evaluated for histological features and immunostaining results of CD3, CD4, CD8, CD20, CD68, CD163, MX1, MHC class I, MHC class II, and HLA-DR. Diagnostic algorithms for IIM were developed based on the results of the classification and regression tree (CART) analysis, which used immunostaining results as predictor variables for classifying patients with IIMs.
RESULTS: In the analysis set (IIM, n = 129; control, n = 73), IIM-related histopathologic features had a diagnostic accuracy of 87.6% (sensitivity 80.6%; specificity 100.0%) for IIMs. Notably, muscular expression of CD163 (99.2% vs. 20.8%, p < 0.001) and MHC class I (87.6% vs. 23.1%, p < 0.001) was significantly higher in the IIM group than in controls. Based on the CART analysis results, we developed an algorithm combining CD163 and MHC class I expression that conferred a diagnostic accuracy of 95.5% (sensitivity 96.1%; specificity 94.5%). In addition, our algorithm was able to correctly diagnose IIM in 94.1% (16/17) of patients who did not meet the 2017 EUALR/ACR criteria but were diagnosed as having IIMs by an expert physician.
CONCLUSIONS: Combination of CD163 and MHC class I muscular expression may be useful in diagnosing IIMs.