Validation of loop-mediated isothermal amplification to detect Helicobacter pylori and 23S rRNA mutations: A prospective, observational clinical cohort study.

Background: Identifying point mutations in 23S rRNA closely associated with clarithromycin resistance can increase the eradication rate of Helicobacter pylori (H pylori). In this study, we verified the sensitivity, specificity, and reliability of a newly developed loop-mediated isothermal amplification (LAMP) assay kit to detect H pylori and 2143G and 2182C mutations in 23S rRNA.

Methods: LAMP assay to detect H pylori and a mutant strain with 2143G and 2182C was conducted with the Isopollo H pylori & ClaR kit. A prospective, open-label, observational study was conducted to validate the reliability of the LAMP assay in both a development cohort and a bedside direct LAMP cohort.

Results: The LAMP assay had good sensitivity, as it could detect as few as 10-100 copies of H pylori and mutants with 2143G and 2182C in 23S rRNA, and good specificity, as it did not react with other bacterial species. In the development cohort with 622 participants, the LAMP assay showed good agreement with RUT for detecting H pylori (kappa value 0.923, P < .001) and had exactly the same results as sequencing analysis for 2143G and 2182C point mutations. The direct LAMP cohort including 93 patients had 97.7% (42/43) of concordance in detecting 2143G and 2182C point mutations compared to the PCR-based sequencing analysis.

Conclusion: The Isopollo H pylori & ClaR LAMP assay was a valid method for detecting H pylori and for 2143G and 2182C point mutations in 23S rRNA in a clinical setting.