Xpert MTB/RIF技术对结核分枝杆菌检测和耐多药结核快速筛查的研究

Study on detection of Mycobacterium tuberculosis and rapid screening of multi drug-resistance with Xpert MTB / RIF technology

目的探讨Xpert MTB/RIF技术检测涂阳痰标本结核分枝杆菌和利福平耐药性的效能,分析该技术在不同利福平耐药率患者中进行耐多药结核诊断的应用价值。方法连续纳入769例涂阳肺结核患者的痰标本,分别进行涂片镜检、固体培养、分枝杆菌初步菌型鉴定、比例法药敏试验和Xpert MTB/RIF检测。结果 Xpert MTB/RIF技术检测结核分枝杆菌的灵敏度为98.15%,特异度为70.00%。检测利福平耐药性与比例法药敏结果比较,Kappa值为0.859,灵敏度为93.04%,特异度为95.71%,复治涂阳患者特异度低于初治涂阳患者,阳性预测值和阴性预测值分别为85.47%和98.07%。结论 Xpert MTB/RIF技术能够快速检测出涂阳痰标本中结核分枝杆菌和利福平耐药性,具有较高的灵敏度和特异度。在云南省用于耐多药结核病患者快速筛查时,优先用于利福平耐药率较高的定点医院以及罹患耐多药高危人群。

Objective To investigate the performance of Xpert MTB / RIF technology on detecting Mycobacterium tuberculosis（ MTB） in smear-positive sputum and rifampin resistance,and to analyze the technology application in patients with different rifampicin resistance rates for diagnosis of MDR-TB. Methods Sputum samples from 769 patients with tuberculosis were collected for smear microscopy,solid culture,mycobacteria preliminary serotype identification and drug conventional drug susceptibility test（ DST） and Xpert MTB / RIF test. Results The sensitivity and specificity of Xpert MTB / RIF test in detecting MTB were 98. 15% and 70. 00%. Compared with the DST result,the Kappa value was 0. 859,the sensitivity and specificity were93. 04% and 95. 71%,the specificity of retreatment patients was lower than new smear positive patients,the positive and negative predictive value were 85. 47% and 98. 07%,respectively. Conclusion Xpert MTB / RIF technology can rapidly detect MTB and rifampin resistance with high sensitivity and specificity. The technology,when rapidly used to screen MDR-TB,is preferentially applied in patients with higher rifampicin drug-resistant rate in designated hospitals or among high risk population suffering from MDR-TB in Yunnan.