Real-Time Polymerase Chain Reaction for the Detection of Helicobacter pylori and Clarithromycin Resistance

Gut Liver. 2023 May 15;17(3):375-381. doi: 10.5009/gnl220076. Epub 2022 Jul 20.

Abstract

Background/aims: Real-time polymerase chain reaction (RT-PCR) is a fast and simple method for the simultaneous detection of clarithromycin (CLR) resistance and Helicobacter pylori. We evaluated the effectiveness of RT-PCR compared to that of the rapid urease test (RUT) and assessed its value in verifying CLR resistance.

Methods: A total of 70 specimens with confirmed H. pylori infection in culture were enrolled and analyzed in this prospective study. All specimens were subjected to RT-PCR assay using fluorescence melting peak signals to detect H. pylori infection and CLR resistances caused by either A2142G or A2143G mutations in the 23S ribosomal RNA gene (23S rRNA). The results were compared to those of RUT and antimicrobial susceptibility culturing tests to investigate the efficacy of RT-PCR.

Results: Among the 70 specimens analyzed, the positivity rate was 97.1% (68/70) with RT-PCR and 82.9% (58/70) with RUT. CLR resistance (minimum inhibitory concentration >1.0 μg/mL) was confirmed in 18.6% (13/70), and fluorescence melting curve analysis showed that 84.6% (11/13) had point mutations in 23S rRNA. Ten specimens had only A2143G mutation, and one specimen contained both A2142G and A2143G mutations.

Conclusions: RT-PCR assay was found to be more efficient than RUT in detecting H. pylori infection and could effectively verify CLR resistance compared to the antimicrobial susceptibility culturing test. Considering the high sensitivity and accessibility of RT-PCR method, it could be used to easily detect CLR-resistant H. pylori, thus helping clinicians select suitable treatment regimen and improve the eradication rate.

Keywords: Clarithromycin resistance; Culture; Helicobacter pylori; Rapid urease test; Real-time polymerase chain reaction.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Clarithromycin / pharmacology
  • Drug Resistance, Bacterial / genetics
  • Helicobacter Infections* / diagnosis
  • Helicobacter Infections* / drug therapy
  • Helicobacter pylori* / genetics
  • Humans
  • Microbial Sensitivity Tests
  • Prospective Studies
  • RNA, Ribosomal, 23S / genetics
  • Real-Time Polymerase Chain Reaction / methods

Substances

  • Clarithromycin
  • Anti-Bacterial Agents
  • RNA, Ribosomal, 23S

Grants and funding

ACKNOWLEDGEMENTS This work was supported by a grant from SK Chemical Research Fund of the Korean Society of Gastroenterology in 2020 and the Korean College of Helicobacter and Upper Gastrointestinal Research Foundation (grant number: KCHUGR-202002501).