Diagnosis of Genitourinary Tuberculosis by Loop-Mediated Isothermal Amplification Based on SYBR Green I Dye Reaction

Abstract

A multitargeted loop-mediated isothermal amplification (MT-LAMP) assay targeting <i>mpt64</i> (Rv1980c) and IS<i>6110</i> was designed to diagnose genitourinary tuberculosis (GUTB) cases. While assessing gel-based, hydroxynaphthol blue (HNB) and SYBR Green I MT-LAMP assays on GUTB specimens (n = 28) in a pilot study, both gel-based/SYBR Green I assays exhibited better sensitivity than HNB LAMP. Since SYBR Green MT-LAMP is easier to perform compared with a gel-based assay, a higher number of GUTB specimens (n = 55) were evaluated by SYBR Green MT-LAMP, wherein 85.5% sensitivity and 94.4% specificity (n = 36) were obtained. Moreover, the sensitivity attained by MT-LAMP was significantly higher (p < 0.05) than with multiplex-PCR (<i>mpt64</i> + IS<i>6110</i>). After further validating these MT-LAMP data in different epidemiological settings, this assay may be developed as a diagnostic kit.