40 years since its discovery, Helicobacter pylori (H.pylori) is the major agent in the development of peptic ulcers and gastric cancers (adenocarcinomas and MALT lymphomas). Treatment of the infection has been shown to be effective in preventing the occurrence of gastric cancers and recurrence of gastric and duodenal ulcers; it leads to a durable remission of low-grade gastric MALT lymphomas. Nevertheless, the progression of bacterial resistance to antibiotics, particularly to clarithromycin (22% of strains), implies adapting therapeutic practices.
Treatments to eradicate H.pylori have been implemented in an empirical manner. In addition, practice surveys and database analysis revealed deviations from recommended practices. For example, triple therapy combining a proton pump inhibitor, amoxicillin and clarithromycin is still sometimes prescribed as first-line probabilistic treatment. The prescription in case of failure of a second line of identical treatment has been observed, hence the emergence of resistance in recent years with antibiotics such as Levofloxacin and Rifampicin.
The aim of my research is to adapt the doses of the antibiotic treatments used in order to eradicate H.pylori and/or to avoid the appearance of resistant mutants. So, this thesis will describe an optimal culture method that will allow to proceed to several bacteriological techniques such as the bactericidal curves and the liquid checkerboard method which are the keys to select the best active combinations against H.pylori. the best antibiotic combinations will be tested on an animal model.