Antimicrobial resistance status of Helicobacter pylori in Eastern Europe

A multicenter study in 19 centers in 10 Eastern European countries to assess primary, secondary and combined resistance to five antimicrobial agents (metronidazole, clarithromycin, amoxicillin, tetracycline and ciprofloxacin) in 2340 H. pylori strains .

The study involved centers in Bulgaria, Croatia, the Czech Republic, Estonia, Greece, Lithuania, Poland, United States, Slovenia and Turkey.

The sensitivity was determined by dilution on agar (7 countries), E tests (5 countries) and diffusion method (3 countries). Primary and secondary resistance were determined in 2003 and 337 strains respectively. The results of a study of the resistance of H. pylori strains isolated from 282 children and 201 adults were compared.

Since 1998, the primary resistance level for metronidazole was 37.9%, clarithromycin 9.5%, amoxicillin 0.9%, tetracycline 1.9%, ciprofloxacin 3.9%, and together for metronidazole and clarithromycin 6, 1%. The strains obtained from Slovenia and Lithuania are characterized by a low level of resistance. Since 1998, the emergence of resistance to amoxicillin in the south-eastern region has been noted. Since 1996, resistance to metronidazole has increased from 30.5% to 36.4%, clarithromycin from 8.9% to 10.6%. In Greece, Poland and Bulgaria, the average level of resistance to metronidazole in adults was slightly higher than in children (39% vs 31.2%, p greater than 0, 05). This pattern was not characteristic of clarithromycin and amoxicillin (p greater than 0.20). The secondary resistance level varied over a wide range.

The results of the study led to the conclusion that in Eastern Europe the level of resistance of H. pylori to metronidazole is significant, while for clarithromycin it is identical or slightly higher than in Western Europe. In several centers, the strains were resistant to amoxicillin, ciprofloxacin and tetracycline. The levels of primary and secondary resistance between centers vary considerably.