评估GeneXpert MTB/RIF技术在结核性脑膜炎诊断中的价值

Evaluation of Gene Xpert MTB/RIF for Diagnosis of Tuberculous Meningitis

目的:探讨GeneXpert MTB/RIF检测技术在结核性脑膜炎(TBM)诊断中的应用价值。方法:收集疑似TBM患者137例,采集患者脑脊液标本,运用抗酸染色法、培养法、GeneXpert MTB/RIF技术进行检测。分别以临床诊断和培养法作为参考标准来评价GeneXpert MTB/RIF对TBM的诊断性能。结果:137例患者中最终纳入124例(90.5%),临床诊断为TBM 51例,非TBM73例。以临床诊断为标准,GeneXpert MTB/RIF、抗酸染色法、培养法在TBM组检测敏感度分别为25.5%(13/51)、3.9%(2/51)、17.6%(9/51),特异性均为100%(73/73)。GeneXpert MTB/RIF敏感性与培养法相比无差异(P=0.336),但显著高于抗酸染色法(P=0.002)。若以结核杆菌培养法作为参考标准,GeneXpert MTB/RIF检测TBM的敏感性为88.9%(8/9),特异性为100%(73/73)。13例经GeneXpert MTB/RIF检测阳性患者中均未检出利福平耐药,与传统药敏结果一致。结论:GeneXpert MTB/RIF技术操作简便、快速,特异性高。

Objective:To evaluate the diagnostic value of GeneXpert MTB/RIF for diagnosis of tuberculous meningitis(TBM).Methods:A total of 137 patients with suspected TBM were prospectively recruited.Samples of cerebrospinal fluid were collected from all patients,and tested by acid fast staining,mycobacterial culture and GeneXpert MTB/RIF.The performance of GeneXpert MTB/RIF was evaluated by two reference standards,clinical diagnosis and mycobacterial culture,respectively.Results:Of the 137 enrolled subjects,124 cases(90.5%)had a final diagnosis,with 51 cases being diagnosed definitive TBM and 73 cases being diagnosed non-TBM.When clinical diagnosis was used as the reference standard,the sensitivities of GeneXpert MTB/RIF.acid fast staining.mycobacterial culture were 25.5%(13/51).3.9%(2/51).17.6%(9/51),respectively.The specificities of the three methods were all 100%.The sensitivity of GeneXpert MTB/RIF was comparable to that of mycobacterial culture(P=0.336),and was significantly higher than that of acid fast staining(P=0.002).When mycobacterial culture was used as the reference standard,the sensitivity of GeneXpert MTB/RIF was 88.9%,and specificity was 100%.Rifampin resistance was not found in the 13 positive results of GeneXpert MTB/RIF assay,which was consistent with traditional drug susceptibility test.Conclusion:GeneXpert MTB/RIF is a simple and rapid diagnostic method with high specificity for Mtb detection.