Diagnostic accuracy of TB-LAMP for pulmonary tuberculosis: a systematic review and meta-analysis

Abstract

BackgroundThe need for a rapid, molecular test to diagnose tuberculosis (TB) has prompted exploration of TB-LAMP (Eiken; Tokyo, Japan) for use in resource-limited settings. We conducted a systematic review to assess the accuracy of TB-LAMP as a diagnostic test for pulmonary TB.MethodsWe analyzed individual-level data for eligible patients from all studies of TB-LAMP conducted between Jan 2012 and October 2015 to compare the diagnostic accuracy of TB-LAMP with that of smear microscopy and Xpert MTB/RIF® using 3 reference standards of varying stringency. Pooled sensitivity and specificity and pooled differences in sensitivity and specificity were estimated using random effects meta-analysis. Study quality was evaluated using QUADAS-2.ResultsFour thousand seven hundred sixty individuals across 13 studies met eligibility criteria. Methodological quality was judged to be low for all studies. TB-LAMP had higher sensitivity than sputum smear microscopy (pooled sensitivity difference + 13·2, 95% CI 4·5–21·9%) and similar sensitivity to Xpert MTB/RIF (pooled sensitivity difference − 2·5, 95% CI -8·0 to + 2·9) using the most stringent reference standard available. Specificity of TB-LAMP was similar to that of sputum smear microscopy (pooled specificity difference − 1·8, 95% CI -3·8 to + 0·2) and Xpert MTB/RIF (pooled specificity difference 0·5, 95% CI -0·9 to + 1·8).ConclusionsFrom the perspective of diagnostic accuracy, TB-LAMP may be considered as an alternative test for sputum smear microscopy. Additional factors such as cost, feasibility, and acceptability in settings that continue to rely on sputum smear microscopy should be considered when deciding to adopt this technology. Xpert MTB/RIF should continue to be preferred in settings where resource and infrastructure requirements are adequate and where HIV co-infection or drug-resistance is of concern.Electronic supplementary materialThe online version of this article (10.1186/s12879-019-3881-y) contains supplementary material, which is available to authorized users.

Pragmatic accuracy of an in-house loop-mediated isothermal amplification (LAMP) for diagnosis of pulmonary tuberculosis in a Thai community hospital

“…Currently, the WHO only endorses the use of two rapid molecular tests for the diagnosis of pulmonary TB, which were Xpert MTB/RIF and the commercialized TB-LAMP assay [ 9 ]. According to previous studies, both had shown comparable performance in smear-positive samples, but higher sensitivity was shown in Xpert MTB/RIF than in the LAMP test [ 6 , 12 ]. Xpert MTB/RIF has been endorsed for use in the diagnosis of TB in many countries, including Thailand [ 4 , 31 ].…”

“…These nucleic amplification techniques were known for yielding rapid and accurate TB diagnosis, which would overcome the limitations of classical methods (ie, insensitivity for smear microscopy and lengthy incubation period for TB culture). However, several obstacles remain for the application of these molecular tests as point-of-care testing in community settings due to their complexity to execute and substantial requirements for financial and personnel resources [ 3 , 6 ]. Loop-mediated isothermal amplification (LAMP) assay is another recently developed nucleic acid amplification technique.…”

“…In 2016, WHO endorsed the use of commercial TB-LAMP assay (Eiken Chemical Co., Tokyo, Japan) as a replacement for smear microscopy for the diagnosis of TB [ 9 ]. TB-LAMP assay has a low cost per test, does not required advanced technological facilities, and can be routinely practiced in general hospital laboratories [ 6 , 10 ].…”

Of tuberculosis and non-tuberculous mycobacterial infections – a comparative analysis of epidemiology, diagnosis and treatment

“…The LAMP-MTBC detection kit, which is endorsed by the WHO, targets the gyrB gene and IS regions of the Mtb complex genome. In this assay, the amplified product is visualized with the naked eye or under ultraviolet (UV) light [47]. In the CPA-based TB diagnostic system, PCR amplification is done at a single temperature using multiple primers and probes of Mtb.…”

Development and application of loop-mediated isothermal amplification label-based nanoparticles lateral flow biosensor for detection of Mycobacterium tuberculosis

“…Isothermal amplification techniques, such as loop-mediated isothermal amplification (LAMP), eliminated the shortcomings posed by traditional smear microcopy, culture-and PCR-based assays, and has been endorsed by the WHO (World Health Organization) in 2016 (Notomi et al 2000;World-Health-Organizaion 2016). Although many LAMP-based assayshave been reported for reliable diagnostic of MTB (Yadav et al 2017;Rakotosamimanana et al 2019;Shete et al 2019;Bojang et al 2016), the TB-LAMP results were determined by agarose gel electrophoresis, colorimetric indicator (SYBR green I or calcein dyes) and real-time turbidity. Particularly, analysis of LAMP result using agarose gel electrophoresis requires an additional process, and easily leads to carryover contamination; recognition of LAMP amplification using colorimetric indicator is potentially subjective, and easily produces ambiguous judgment; detection of the LAMP products using real-time turbidity needs an expensive optical instrument (Zhang et al 2014).…”