两种结核分枝杆菌感染检测试剂盒性能的评估

Comparison of detection performances between two kits for mycobacterium tuberculosis infection

目的评估两种γ干扰素(IFN-γ)释放试验(IGRA)检测结核分枝杆菌(MTB)感染试剂盒的临床检验性能。方法共检测105份临床血液标本(结核组61份,非结核性肺部疾病组31份,健康对照组13份),其中两种试剂对比检测82份(结核组43份,非结核性肺部疾病组26份,健康对照组13份),以澳大利亚Cellestis公司的QuantiFERON-TB Gold产品为参比试剂,评估考核试剂对感染判定的准确性;并对结核组与健康对照组的IFN-γ释放水平进行分析,初步探讨结核患者的基础免疫状况。结果参比试剂对诊断结核感染的敏感性为81.39%(35/43),特异性为76.92%(30/39),阳性预测值为79.55%(35/44),阴性预测值为78.95%(30/38),诊断有效性为79.27%(65/82);考核试剂对结核感染诊断的敏感性为73.77%(45/61),特异性为84.09%(37/44),阳性预测值为86.54%(45/52),阴性预测值为69.81%(37/53),诊断有效性为78.09%(82/105),两种试剂的检测结果有86.56%的一致率(Kappa=0.734);结核组IFN-γ的释放水平显著高于健康对照组(t=2.529,P=0.014)。结论考核试剂与参比试剂检测性能相当,对辅助诊断MTB感染有指导意义;结核患者T细胞活性可能存在着某种程度的反应性增高。

Objective To evaluate the detection performances of two interferon-gamma(IFN-γ)release assay(IGRA) kits for mycobacterium tuberculosis(MTB) infection. MethodsOne hundred and five clinical blood samples were detected(61 in tuberculosis group,31 in nontuberculous pulmonary disease group,and 13 in healthy control group),82 of which were detected with two kits contrastively(43 in tuberculosis group,26 in nontuberculous pulmonary disease group,and 13 in healthy control group),and QuantiFERON-TB Gold(Cellestis,Australia) was served as reference kit to calculate the accuracy of test kit in detection of infection and to explore the basic immune status by counting the quantity of IFN-γ in tuberculosis group and healthy control group. ResultsThe sensitivity,specificity,positive predictive value,negative predictive value and diagnostic validity of reference kit were 81.39%(35/43),76.92%(30/39),79.55%(35/44),78.95%(30/38) and 79.27%(65/82) respectively,and those of test kit were 73.77%(45/61),84.09%(37/44),86.54%(45/52),69.81%(37/53) and 78.09%(82/105) respectively.The coincidence rate of two kits was 86.56%(Kappa=0.734).The quantity of IFN-γ after stimulation in tuberculosis group was significantly higher than that in healthy control group(t=2.529,P=0.014). ConclusionThe detection performances of test kit and reference kit are almost the same,and both kits can work for the auxiliary diagnosis of MTB infection.T cell activity may be increased reactively to some extent in patients with tuberculosis.