Objective: The choice of the Helicobacter pylori (H. pylori) eradication regimen should depend on the antibiotic resistance of this major gastric pathogen. In Latvia, resistance patterns of H. pylori strains have not been described in the general population. The aim of the study is to evaluate the primary susceptibility of H. pylori to antibiotics used in recommended eradication regimens for the middle-aged population in Latvia.

Materials and Methods: H. pylori antibiotic resistance was assessed in asymptomatic individuals aged 40-64 years, recruited as part of the GISTAR pilot study. H. pylori culture was recovered from initially frozen biopsies taken during the endoscopic examinations. Antimicrobial susceptibility to metronidazole, clarithromycin, amoxicillin, tetracycline, rifampicin, and levofloxacin was successfully determined in 89 isolates using the Epsilomer test (E-test, BioMerieux, France), and interpreted according to EUCAST clinical breakpoint standard.

Results: Among the 89 tested isolates, 49 isolates (55%) were resistant to at least one of the tested antibiotics. Resistance to metronidazole was detected in 31 cases (34.8%; 95% CI: 25.2-45.7), followed by rifampicin in nine cases (10.1%; 95% CI: 5.0-18.8%), clarithromycin in five (5.6%; 95% CI: 2.1-13.2) and to levofloxacin in four cases (4.5%; 95% CI: 1.5-11.8). None of the cultures displayed resistance to tetracycline or amoxicillin. Eight resistance patterns were detected: 34 participants had resistance to one of the tested antibiotics; six participants had double resistance, and one participant had resistance to metronidazole, clarithromycin, and levofloxacin.

Conclusions: H. pylori’s primary resistance to clarithromycin is still low; therefore, the use of standard clarithromycin-based triple therapies may be justified as the first-line therapy for H. pylori eradication in the middle-aged population in Latvia.