Antimicrobial susceptibility of Helicobacter pylori isolates from Lower Silesia, Poland

In recent years the failure of standard therapy for Helicobacter pylori infections has been observed, which results primarily from the increasing resistance of H. pylori strains to antibiotics. The aim of the study was to estimate the prevalence of antimicrobial resistance of H. pylori strains isolated from adult symptomatic patients with primary infection in the Lower Silesia Region in Poland.

One hundred and seventy-eight adults aged 19-89 years with dyspeptic symptoms suggesting gastroduodenal pathology were enrolled in the study. The study was performed in the years 2008-2011. Fifty H. pylori strains were isolated from gastric biopsy samples of examined patients. Antimicrobial susceptibility to 6 drugs (amoxicillin (AM), clarithromycin (CH), metronidazole (MZ), tetracycline (TC), levofloxacin (LEV), and rifabutin (RB)) was tested by the gradient-diffusion method (E-test method).

The incidence of H. pylori infection among examined patients was 35%. From 50 isolated H. pylori strains, 24% showed resistance to CH, 42% to MZ and 8% to LEV alone. Multidrug resistance was detected in 26% of strains, whereas 20% of isolates were resistant to MZ and CH. Examined strains were fully susceptible to AM, TC and RB.

Resistance to clarithromycin strains isolated from adults of the Lower Silesia Region in Poland is high and is almost always associated with resistance to metronidazole (CH + MZ). It is necessary to continuously monitor H. pylori resistance to drugs used in therapy, especially to clarithromycin. Verification of the existing recommendations of eradication therapy is also needed.