Multiplex Mediator Displacement Loop-Mediated Isothermal Amplification for Detection of Treponema pallidum and Haemophilus ducreyi

18 Jan 2020
Lisa Becherer, Sascha Knauf, Michael Marks, Simone Lueert, Sieghard Frischmann, Nadine Borst, Felix von Stetten, Sibauk Bieb, Yaw Adu-Sarkodie, Kingsley Asiedu, Oriol Mitjà1, and Mohammed Bakheit

 

Abstract

Yaws, a neglected tropical disease caused by the bacterium Treponema pallidumsubspecies pertenue, manifests as ulcerative skin lesions. Nucleic acid amplification tests, like loop-mediated isothermal amplification (LAMP), are versatile tools to distinguish yaws from infections that cause similar skin lesions, primarily Haemophilus ducreyi. We developed a novel molecular test to simultaneously detect T. pallidum and H. ducreyi based on mediator displacement LAMP. We validated the T. pallidum and H. ducreyi LAMP (TPHD-LAMP) by testing 293 clinical samples from patients with yaws-like lesions. Compared with quantitative PCR, the TPHD-LAMP demonstrated high sensitivity and specificity for T. pallidum (84.7% sensitivity, 95.7% specificity) and H. ducreyi(91.6% sensitivity, 84.8% specificity). This novel assay provided rapid molecular confirmation of T. pallidum and H. ducreyi DNA and might be suitable for use at the point of care. TPHD-LAMP could support yaws eradication by improving access to molecular diagnostic tests at the district hospital level.