Resistance rates of metronidazole and other antibacterials in Helicobacter pylori from previously untreated patients in Norway

Abstract

The aim of the study was to describe the antimicrobial resistance rate of Helicobacter pylori isolated from previously untreated patients in Norway, including the application of two different methods for the determination of metronidazole susceptibility. Altogether 102 isolates obtained in 2008 and 2009 from previously untreated patients suspected of H. pylori related disease, were examined applying a standardized European study protocol. The activity of amoxicillin, tetracycline, clarithromycin, metronidazole, rifabutin and levofloxacin was recorded after an incubation period of 72-96 h in a microaerobic atmosphere. Strains resistant to metronidazole were re-examined for metronidazole resistance applying anaerobic conditions for the first 24 h. None of the isolates were resistant to amoxicillin or tetracycline, whereas 5, 9% were resistant to clarithromycin and 22, 5% resistant to metronidazole tested conventionally. Applying local standards the metronidazole resistance rate fell to 7, 8%, highlighting the importance of the methodology applied for metronidazole susceptibility testing.

Antimicrobial resistance of Helicobacter pylori strains to five antibiotics, including levofloxacin, in Northwestern Turkey

“…In 2013, Megraud et al (19) reported 0.7% and 0.9% amoxicillin and tetracycline resistance rates, respectively. Wueppenhorstet al (20) and Larsen et al (21) in Norway reported H. pylori amoxicillin and tetracycline resistance rates of 1.4% and 0% in Germany and 10% and 0% in Norway, respectively. Cuadrado-Lavínet al (27) in Spain and Georgopoulos et al (17) in Greece reported no amoxicillin resistance.…”

“…Similarly high clarithromycin resistance rates have been reported in Italy and Germany, at 53% and 67.1%, respectively (9) (20) . A contrasting example is Norway, where macrolides are rarely selected as a treatment option; there, the prevalence of clarithromycin resistance was reported to be 5.9% (21) . In East Asian countries such as Japan (27.2%), South Korea (23.7%) and China (65.4%), high clarithromycin resistance rates have been reported.…”

Antibiotic treatment forHelicobacter pylori: Is the end coming?

“…Another study showed that 80% of strains in Mexico were resistant to metronidazole [55] . Overall, metronidazole resistance is > 50% in much of the world but there are reports that metronidazole resistance has declined in Northern Europe [9,30] , while in the United States and Europe, the metronidazole resistance rate was reported to be < 40% [30,56] , and 22.5% in 102 isolates from Norway [57] . However, in Central and Southern Europe, resistance rates remain markedly higher-34.9% in France and 32.7% in Germany [47,58] .…”

Trends in Secondary Antibiotic Resistance of Helicobacter pylori from 2007 to 2014: Has the Tide Turned?

“…Previous reports have shown that incubation for 24 h in anaerobic conditions before transferring to a microaerobic atmosphere yields significantly lower MET resistance than incubation which is exclusively microaerobic (31). The reason is that the nitro group of metronidazole must be reduced for drug activation.…”