全血γ-干扰素释放试验对结核病的诊断价值

To evaluate the diganositic value of interfron-gamma release assay tuberculosis for tuberculosis in the peropheral blood mononuclear cells

目的评价全血γ-干扰素释放试验（TB-IGRA）在疑似或待排除结核性疾病中的临床应用价值。方法收集2014年1月至2015年12月在蚌埠医学院第一附属医院安徽省呼吸病重点实验室进行TB-IGRA检测的823例疑似或待排结核病患者的临床资料，将TB-IGRA结果与患者临床诊断对比，进而评价TB-IGRA试验的敏感度、特异度、阳性预测值、阴性预测值等，并与PPD的诊断效能相比较，同时对可能造成TB-IGRA试验结果假阴性的影响的因素进行分析；结果823例患者中，诊断为活动性结核病共260例（确诊活动性结核43例，临床诊断活动性结核病217例），非活动性结核病563例。TB-IGRA总敏感度为86．9％（226／260），特异度为82．4％（464／563），阳性预测值为69．5％（226／325），阴性预测值为93．2％（464／498）；年龄、合并糖尿病、长期使用激素或免疫抑制剂、炎症状态、淋巴细胞计数减低均不是导致TB-IGRA假阴性的影响因素；133例患者同时进行了PPD检查，PPD试验诊断活动性结核病的总敏感度为73．5％（50／68），特异度为69．2％（45／65）、阳性预测值71．4％（50／70）、阴性预测值71．4％（45／63）。结论TB-IGRA诊断结核病的敏感度和特异度较高，均优于PPD，有良好的临床诊断价值。

Objective To evaluate the diganositic value of interfron-gamma release assay TB for tuberculosis in the peropheral blood mononuclear cells. Methods We analyzed the interfron-gamma release assay tuberculosis （TB-IGRA） results and clinic datas of 823 tuberculosis suspects who were admitted to the First Affiliated Hospital of Bengbu Medical College from January 2014 to December 2015. The sensitivity, specificity, positive predictive value, negative predictive value of TB-IGRA were analyzed according to the final diagnosis, comparing to the PPD, meanwhile, analyzing influence factors which may caused results of false negative. Results Two hundred and sixty patients were eventually diagnosed to have TB. Among 43 patients with laboratory diagnosis of TB, 217 patients with clinic diagnosis of TB, others with not TB, 226 were TB-IGRA positive and the sensitivity was 86.9% （226/260） ;specificity was 82.4%（464/563）, positive predictive value was 69.5% （226/325）, negative predictive value was 93.2% （464/498） ;Influence factors caused false negative not including age, diabetes, long-term use of hormone or immune inhibitors, inflammatory state, low lymphocyte count;One hundred and thirty-three patients were retested by the TB-PPD, the sensitivity was 73.5%（50/68） ; specificity was 69.2%（45/65）, positive predictive value was 71.4% （50/70）, negative predictive value was 71.4% （45/63）. Conclusions TB-IGRA is a promising test for the diagnosis of tuberculosis due to its high sensitivity and specificity, which has a good clinical diagnostic value, superior to PPD.