Department of Pediatrics, Sarojini Naidu Medical College, Agra, India.
Department of Pediatrics, Dr Ram Manohar Lohia Institute of Medical Sciences, India.
J Pediatric Infect Dis Soc. 2021 Mar 26;10(2):83-87. doi: 10.1093/jpids/piaa019.
Cartridge-based nucleic acid amplification test (CB-NAAT) has been recommended for diagnosis of tuberculosis (TB) in children, but its wide use is limited by high cost and the need for well-equipped laboratories. This study was conducted in children with pulmonary TB to compare the diagnostic yield of TB-LAMP (loop-mediated isothermal amplification test) with CB-NAAT and other conventional methods.
Patients ≤ 14 years of age diagnosed with probable pulmonary TB were included in the study. Induced sputum/gastric aspirate was obtained and subjected to acid-fast bacilli (AFB) microscopy, mycobacteria growth indicator tube (MGIT) culture, CB-NAAT, and TB-LAMP. The TB-LAMP assay was performed using 2 different primers, IS6110 and mpb64, for detection of Mycobacterium tuberculosis (MTB). TB-LAMP assays were compared to other assays using appropriate statistical tests.
One hundred fourteen subjects were recruited in the study. AFB microscopy, MGIT culture, CB-NAAT, TB-LAMP IS6110, and TB-LAMP mpb64 showed positivity of 32 (28.1%), 59 (51.7%), 66 (57.9%), 75 (65.8%), and 81 (71%), respectively. TB-LAMP IS6110 showed significantly higher MTB detection in comparison to AFB microscopy and MGIT culture (P = .0001 and P = .03, respectively), and showed no significant difference in MTB detection in comparison with CB-NAAT (P = .219). TB-LAMP mpb64 showed significantly higher MTB detection as compared to AFB microscopy, MGIT culture, and CB-NAAT (P = .0001, P = .003, and P = .037, respectively). TB-LAMP mpb64 and IS6110 showed sensitivity of 94.9% (95% confidence interval [CI], 85.9%-98.9%) and 89.8% (95% CI, 79.7%-96.2%), respectively, in reference to MGIT culture. The degree of agreement between TB-LAMP (mpb64 and IS6110) with CB-NAAT showed κ values of 0.718 and 0.834, respectively.
TB-LAMP assay can be a useful alternative test in diagnosis of pulmonary TB in children.
基于试剂盒的核酸扩增测试（CB-NAAT）已被推荐用于儿童结核病（TB）的诊断，但由于成本高且需要设备齐全的实验室，其广泛应用受到限制。本研究旨在比较 TB-LAMP（环介导等温扩增测试）与 CB-NAAT 和其他常规方法在诊断儿童肺结核中的诊断效果。
本研究纳入了疑似患有肺结核的≤14 岁患儿。采集诱导痰/胃抽吸物进行抗酸杆菌（AFB）镜检、分枝杆菌生长指示管（MGIT）培养、CB-NAAT 和 TB-LAMP。TB-LAMP 检测使用了两种不同的引物，IS6110 和 mpb64，用于检测结核分枝杆菌（MTB）。使用适当的统计检验比较 TB-LAMP 检测与其他检测方法的结果。
本研究共纳入 114 例患者。AFB 镜检、MGIT 培养、CB-NAAT、TB-LAMP IS6110 和 TB-LAMP mpb64 的阳性率分别为 32（28.1%）、59（51.7%）、66（57.9%）、75（65.8%）和 81（71%）。TB-LAMP IS6110 与 AFB 镜检和 MGIT 培养相比，MTB 检测的阳性率显著更高（P=0.0001 和 P=0.03），与 CB-NAAT 相比，MTB 检测的阳性率无显著差异（P=0.219）。TB-LAMP mpb64 与 AFB 镜检、MGIT 培养和 CB-NAAT 相比，MTB 检测的阳性率显著更高（P=0.0001、P=0.003 和 P=0.037）。TB-LAMP mpb64 和 IS6110 与 MGIT 培养相比，灵敏度分别为 94.9%（95%置信区间[CI]，85.9%-98.9%）和 89.8%（95% CI，79.7%-96.2%）。TB-LAMP（mpb64 和 IS6110）与 CB-NAAT 的一致性程度分别为κ值 0.718 和 0.834。
TB-LAMP 检测可作为儿童肺结核诊断的一种有用的替代检测方法。
