GeneXpert Mtb/RIF检测技术在结核病诊断中的应用评价

目的 评估GeneXpert Mtb/RIF检测技术对肺结核诊断和耐利福平肺结核筛查的效果,为筛选最佳实验室检测方法提供依据。方法 收集三亚市定点医院结核病门诊2015年5月—2016年12月243例临床诊断为肺结核的痰标本,分别进行涂片镜检、痰培养和GeneXpert Mtb/RIF检测,分析三种方法的敏感度和特异度。以比例法药敏为标准,分析GeneXpert检测利福平耐药的敏感度和特异度。结果 涂片镜检与GeneXpertMtb/RIF对比,GeneXpertMtb/RIF检测结核菌的敏感度为93.7%,特异度为28.9%,GeneXpertMtb/RIF检测与涂片镜检一致率为83.5%。痰培养与GeneXpertMtb/RIF对比,GeneXpert检测结核菌的敏感度为96.7%,特异度为56.6%,GeneXpert检测与痰培养的一致率为91.8%。利福平耐药大多与rpoB基因突变有关,GeneXpertMtb/RIF检测利福平耐药与比例法药敏一致率为98.1%, 敏感度为88.9%,特异度为98.9%,并且可检测出利福平耐药基因位点。结论 GeneXpert Mtb/RIF 检测技术适用于结核分枝杆菌及耐药结核分枝杆菌的快速筛查,在痰涂片和痰培养上补充GeneXpertMtb/RIF检测可提高病原学检出率,尽早发现耐多药病患。

Evaluation of GeneXpert Mtb/RIF detection in tuberculosis diagnosis

Objective To evaluate the effect of GeneXpert Mtb/RIF detection on tuberculosis diagnosis and rifampicin-resistant tuberculosis screening, so as to provide the evidence for screening the best laboratory testing Methods. Methods The sputum specimens of 243 clinically diagnosed tuberculosis patients were collected in the fixed-point hospitals from May 2015 to December 2016. The sputum specimens were examined with the smear microscopy, sputum solid culture and GeneXpert Mtb/RIF. The sensitivity and specificity of the three Methods were analyzed with the tuberculosis diagnose standard. The sensitivity and specificity of GeneXpert in the detection of rifampicin resistance were analyzed by the proportional method. Results Whit clinical diagnosis as the gold standard and with the smear microscopy result contrast, the sensitivity and specificity of GeneXpert were 93.7% and 28.9% respectively. The coincidence rate of GeneXpert detection and smear microscopy was 83.5%. Compared with the sputum solid culture, the sensitivity and specificity of GeneXpert to Mycobacterium tuberculosis were 96.7% and 56.6% respectively. The coincidence rate of GeneXpert and sputum solid culture was 91.8%. The studies showed that rifampicin resistance was mostly related to rpoB gene mutation. The consistent rate of GeneXpert detecting rifampicin resistance with the solid drug sensitivity detection was 98.1%, the sensitivity was 88.9%, and the specificity was 98.9%, and in addition, the rifampicin-resistant gene loci could be detected. Conclusion The GeneXpert Mtb/RIF detection technology is suitable for rapid screening of Mycobacterium tuberculosis and drug-resistant Mycobacterium tuberculosis, it can supplement the smear microscopy and sputum solid culture, so as to improve the detection rate of the etiology and early find the patients with multi drug resistance.