γ-干扰素释放试验对肺结核与肺外结核诊断的敏感性和特异性观察

Sensitivity and specificity of interferon gamma release assay in diagnosis of tuberculosis and extrapulmonary tuberculosis

目的探讨肺结核与肺外结核γ-干扰素释放试验(IGRAs)在肺结核和肺外结核诊断中的应用价值。方法选择该院2014年7月至2015年7月住院结核病疑似病例217例,常规进行相关检测及IGRAs试验,所有患者随访3个月,根据结核诊断依据分为2组,结核确诊和临床诊断组81例,无结核证据组136例,观察IGRAs试验结果。结果IGRAs试验敏感度为93.83%(76/81),其中肺结核和肺外结核的敏感度分别为95.74%、91.17%,敏感度比较差异无统计学意义(P>0.05)。特异度为84.56%(115/136)。其中肺结核和肺外结核的特异度分别为80.00%、91.07%,肺外结核的特异度明显高于肺结核,差异具有统计学意义(P<0.05)。5个单位皮肤试验敏感度和特异度分别为56.79%、62.50%。IGRAs试验敏感度、特异度、阳性预测值、阴性预测值均高于TST皮肤试验,差异具有统计学意义(P<0.05)。结论 IGRAs试验在肺结核与肺外结核中有较高敏感度和特异度,特别是在排除结核的诊断上具有较高的临床价值。

Objective To observe sensitivity and specificity of interferon gamma release assay（IGRAs）in the diagnosis of pulmonary tuberculosis and extrapulmonary tuberculosis.Methods Totally 217 cases of suspected tuberculosis from July 2014 to July2015were chosen in the hospital,and relevant tests for routine and IGRAs were performed in the subjects.All patients were followed up for 3months,and divided into two groups on the basis of tuberculosis diagnosis,including the group of confirmed tuberculosis（81cases）and the group of tuberculosis without evidence group（136cases）.The results of IGRAs were observed.Results In the IGRAs test,sensitivity was 93.83%（76/81）,which of the IGRAs in diagnosis of tuberculosis and extrapulmonary tuberculosis were 95.74% and 91.17%,respectively.And there was no significant difference in sensitivity（P〉0.05）.Specificity of IGRAs was84.56%（115/136）,which of the IGRAs in diagnosis of tuberculosis and extrapulmonary tuberculosis were 80.00% and 91.07%,and the specificity of extrapulmonary tuberculosis was significantly higher than that of tuberculosis（P〈0.05）.The sensitivity and specificity in the five units of skin test were 56.79% and 62.50% respectively.And the sensitivity,specificity,positive predictive value,negative predictive value in IGRAs test were significantly higher than in tuberculin skin test（TST）（P〈0.05）.ConclusionIGRAs has higher sensitivity and specificity in the diagnosis of tuberculosis and extrapulmonary tuberculosis,which has higher clinical value especially on excluding the diagnosis of tuberculosis.