T-SPOT.TB和GeneXpertMTB/RIF检测在结核诊断中的应用

Comparision of IFN-γrelease assays and GeneXpertMTB/RIF test in diagnosis of tuberculosis

目的:比较γ-干扰素释放实验(T-SPOT.TB)和GeneXpertMTB/RIF 2种方法对结核病的诊断价值。方法:采集273例结核病患者与45例健康对照者全血,采用T-SPOT.TB检测结核特异性抗原致敏T淋巴细胞,同时收集结核病患者痰液标本采用抗酸染色法进行抗酸杆菌筛查、GeneXpertMTB/RIF进行MTB-DNA和利福平(RIF)耐药检测。结果:273例结核病患者中抗酸染色、T-SPOT.TB和GeneXpertMTB/RIF的敏感性分别为26.74%(73/273)、89.74%(245/273)和72.53%(198/273),特异性分别为100%、93.33%和100%,阳性预测值分别为100%、98.79%和100%,阴性预测值分别为18.37%、60.00%和37.50%,准确性分别为37.11%、90.25%和76.42%,3种方法的敏感性差异有统计学意义(χ~2=248.39,P<0.01)。3种方法对肺结核的检出率分别为34.76%(73/210)、90.00%(189/210)和94.29%(198/210),差异有统计学意义(χ~2=234.937,P<0.01)。3种方法对肺外结核的检出率分别为0(0/63)、88.88%(56/63)和0(0/63)。抗酸染色阳性的肺结核患者中TSPOT.TB和GeneXpertMTB/RIF的阳性率分别为93.15%(68/73)和100%(73/73),抗酸染色阴性肺结核患者T-SPOT.TB和Genexpert MTB/RIF的阳性率为88.32%(121/137)和91.24%(125/137)。结论:T-SPOT.TB和GeneXpertMTB/RIF 2种方法对诊断结核病和肺结核的诊断效能明显优于抗酸染色,T-SPOT.TB对肺外结核患者有更高的检出率。

Objective：To evaluate and compare the clinical application of interferon-γrelease assays（IGRA）and GeneXpertMTB/RIF in the diagnosis of tuberculosis.Method：A total of 273 cases of tuberculosis and 45 healthy controls were enrolled.Direct smear of sputum was used with Ziehl-Neelsen acid-fast bacilli staining to detect tubercle bacillus.T-SPOT.TB was conducted to examine the specific T lymphocytes of tuberculosis.GeneXpertMTB/RIF was operated strictly following the manufacturer＇s instructions.Result：The sensitivity of acid-fast bacilli staining,T-SPOT.TB and GeneXpertMTB/RIF was 26.74%,89.74% and 72.53%（χ-2=234.937,P〈0.01）,respectively.The specificity was 100%,93.33% and 100%,respectively.The positive value （PPV） was 100%,98.79% and 100%,respectively.The negative predictive value（NPV）was 18.37%,60.00% and 37.50%,respectively.The accuracy was 37.11%,90.25% and 76.42%,respectively.The positive rate of three methods was 34.76%,90.00% and 94.29% in pulmonary tuberculosis （χ^2=248.39,P 0.01）,while 0,88.88% and 0 in extrapulmonary tuberculosis.In addition,the positive rate of T-SPOT.TB and GeneXpertMTB/RIF in acid-fast staining positive pulmonary tuberculosis was 93.15% and 100%,while 88.32% and 91.24% in acid-fast staining negative pulmonary tuberculosis.Conclusion：T-SPOT.TB and GeneXpertMTB/RIF might have higher diagnosis efficiency than acid-fast staining and could be useful in evaluating tuberculosis infection.TSPOT.TB may be better than GeneXpertMTB/RIF in extrapulmonary tuberculosis diagnosis.