Antibiotic susceptibility of Helicobacter pylori in Iceland

Infect Dis (Lond). 2017 Sep;49(9):647-654. doi: 10.1080/23744235.2017.1317359. Epub 2017 Apr 25.

Abstract

Background: Increasing resistance of Helicobacter pylori (H. pylori) to antibiotics calls for constant re-evaluation of multidrug regimens that have been used to eradicate the infection. The aim of this study was to evaluate the current antibiotic susceptibility of H. pylori in an Icelandic cohort.

Methods: Patients referred for gastroscopy were recruited prospectively. Those found to have a positive rapid urease test were included in the study. Susceptibility testing was conducted by the Epsilometer test (E-test) method for ampicillin, clarithromycin, levofloxacin, metronidazole and tetracycline. Results were obtained after three days of incubation in microaerophilic conditions at 37 °C, except for the metronidazole were the first 24 hours were anaerobic.

Results: Of the 613 patients who underwent gastroscopy, 138 (23%) had a positive rapid urease test. H. pylori was successfully cultured from 105 (76%) of the urease test positive patients and the isolates were tested for antibiotic susceptibility. Five patients had prior H. pylori eradication. Antibiotic resistance for ampicillin, clarithromycin, levofloxacin, metronidazole and tetracycline was 0%, 9%, 4%, 1% and 0%, respectively. If those who had previously undergone eradication treatment were excluded, the resistance was 0%, 6%, 3%, 1% and 0%, respectively. Clarithromycin resistance was higher amongst women than men, 13% vs. 5%, however, not significantly. Clarithromycin resistance was 60% amongst those who had previously received eradication treatment compared to 6% of those who had not (p < .0001).

Conclusions: Clarithromycin resistance amongst the H. pylori isolates can be considered relatively low. Therefore, in the current cohort, standard triple-drug clarithromycin-containing regimen should remain the first-line treatment against H. pylori.

Keywords: E-test; Helicobacter pylori; antibiotic susceptibility.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / pharmacology*
  • Anti-Bacterial Agents / therapeutic use*
  • Clarithromycin / administration & dosage
  • Clarithromycin / pharmacology
  • Clarithromycin / therapeutic use
  • Drug Resistance, Multiple, Bacterial*
  • Drug Therapy, Combination
  • Female
  • Gastroscopy
  • Helicobacter Infections / drug therapy
  • Helicobacter Infections / epidemiology
  • Helicobacter Infections / microbiology*
  • Helicobacter pylori / drug effects*
  • Humans
  • Iceland / epidemiology
  • Levofloxacin / administration & dosage
  • Levofloxacin / pharmacology
  • Levofloxacin / therapeutic use
  • Male
  • Metronidazole / administration & dosage
  • Metronidazole / pharmacology
  • Metronidazole / therapeutic use
  • Microbial Sensitivity Tests
  • Middle Aged
  • Prospective Studies
  • Young Adult

Substances

  • Anti-Bacterial Agents
  • Metronidazole
  • Levofloxacin
  • Clarithromycin