Sharma Gaurav, Malhotra Bharti, John P J, Gautam Swati, Bhargava Shipra
Department of Microbiology and Immunology, SMS Medical College, Jaipur, Rajasthan, India; Department of Zoology, University of Rajasthan, Jaipur, Rajasthan, India.
Department of Microbiology and Immunology, SMS Medical College, Jaipur, Rajasthan, India.
Indian J Med Microbiol. 2022 Oct-Dec;40(4):547-551. doi: 10.1016/j.ijmmb.2022.07.010. Epub 2022 Aug 18.
Evaluation of GeneXpert in comparison to liquid culture using Mycobacteria Growth Indicator Tube (MGIT) as gold standard for detection of Mycobacterium tuberculosis (MTB) in children.
A total of 8123 samples, both pulmonary (5830) and extra pulmonary (2293) received from pediatric patients were processed for Acid Fast Bacilli (AFB) smear, GeneXpert and MGIT culture simultaneously.
Out of 8123 samples, 493 (6.1%) samples were found positive by GeneXpert and 508 (6.2%) samples by MGIT culture, 371 (4.6%) were found positive by both GeneXpert and MGIT culture. MGIT detected 137 (1.7%) extra positive than GeneXpert while GeneXpert detected 122 (1.5%) extra samples more positive than by MGIT. Sensitivity of GeneXpert was 73% and concordance between both methods was 96.8%. Rifampicin resistance was found in 49 (9.9%) samples among MTB positive by GeneXpert. Turnaround time for GeneXpert was approx. 2 h and for MGIT, it was 12-28 days.
Good sensitivity (73%) and concordance (96.8%) were observed for GeneXpert against MGIT culture in this study. GeneXpert can simultaneously detect MTB and rifampicin resistance in less than 2 h while MGIT takes 12-28 days for MTB detection only.
将GeneXpert与使用分枝杆菌生长指示管（MGIT）的液体培养法进行比较，以MGIT作为检测儿童结核分枝杆菌（MTB）的金标准。
对从儿科患者处接收的总共8123份样本（其中肺部样本5830份，肺外样本2293份）同时进行抗酸杆菌（AFB）涂片、GeneXpert检测和MGIT培养。
在8123份样本中，GeneXpert检测出493份（6.1%）样本呈阳性，MGIT培养检测出508份（6.2%）样本呈阳性，GeneXpert和MGIT培养均检测出371份（4.6%）样本呈阳性。MGIT检测出比GeneXpert多137份（1.7%）的额外阳性样本，而GeneXpert检测出比MGIT多122份（1.5%）的额外阳性样本。GeneXpert的灵敏度为73%，两种方法之间的一致性为96.8%。在GeneXpert检测为MTB阳性的样本中，发现49份（9.9%）样本存在利福平耐药性。GeneXpert的周转时间约为2小时，MGIT的周转时间为12 - 28天。
在本研究中，观察到GeneXpert相对于MGIT培养具有良好的灵敏度（73%）和一致性（96.8%）。GeneXpert可在不到2小时内同时检测MTB和利福平耐药性，而MGIT仅检测MTB就需要12 - 28天。
