Antibiotic resistance and therapy outcome in H. pylori eradication failure patients.

Abstract: Helicobacter pylori (H. pylori) eradication fails in a definite amount of patients despite one or more therapeutic attempts. Curing these patients is progressively more dicult, due to development of antibiotic resistance. Current guidelines suggest testing antibiotic susceptibility in H. pylori isolates following two therapeutic attempts. Aim: to evaluate the development of antibiotic resistance, MIC values trends and therapeutic outcomes in patients who failed at least one H. pylori eradication therapy. Methods: consecutive patients, referred to perform upper gastrointestinal endoscopy (UGIE) to our Unit from January 2009 to January 2019 following at least one therapeutic attempt were considered. Bacterial resistance towards clarithromycin, metronidazole and levofloxacin was tested. Patients received either a susceptibility-guided therapy or Pylera®. Results: a total of 1223 patients were H. pylori positive, and antibiotic susceptibility was available for 1037. The rate of antibiotic resistance and MIC values significantly increased paralleling the number of previous therapeutic attempts. Eradication rates of antibiogram-tailored therapies remained stable, except for the sequential therapy if used as a third line. As a rescue treatment, the Pylera® therapy achieved cure rates comparable to those of the other culture-guided therapies. Conclusions: A significant increase in the secondary resistance towards the three tested antibiotics was observed, both as rate and MIC values, in correlation with the number of therapy failures. These findings should be considered when administering an empirical second-line therapy. Pylera® therapy eradication rates are comparable to culture-tailored therapies.