Non-bismuth quadruple therapies have been proposed as potential strategies in improving the efficacy of first-line treatments. The non-bismuth quadruple therapy in its concomitant variant consists of proton pump inhibitor, amoxicillin, nitroimidazole and clarithromycin given concurrently twice daily. As a result of concurrent administration this therapy has given better results according to some studies in comparison to sequential variants. However, this therapy, as well suffers from the aforementioned increase in antibiotic resistance. Therefore, the aim of this study was to compare concomitant non-bismuth quadruple therapy with a tailored therapy based on antibiotic strain susceptibility testing.

More than half of world population are H.pylori carriers. The infection is mostly acquired in childhood and persists lifelong. A notable risk factor is a lower social and economic status during childhood reflecting mostly poor hygienic standard or small and dense living area. Newly acquired infections in adulthood are a rarity. The reservoir of H. Pylori is the human stomach. H. pylori is considered to be the main pathogen involved in causing benign peptic ulcer and functional dyspepsia as well as gastric cancer. The treatment of H. Pylori infection is currently complicated by an increase in antimicrobial resistance in different parts of the world. Corresponding increase in clarithromycin as well as quinolone and metronidazole resistance poses a major clinical problem and calls for a new approach to treatment. Under such circumstances there is an emerging trend towards personalized eradication therapy. Since H. Pylori infection is an infectious disease its optimal treatment should both theoretically and practically be based on the specific characteristics of the strain and if possible the host of the infection. The aim of such an approach should be a better eradication efficacy.

Non-bismuth quadruple therapies have been proposed as potential strategies in improving the efficacy of first-line treatments. The non-bismuth quadruple therapy in its concomitant variant consists of proton pump inhibitor, amoxicillin, nitroimidazole and clarithromycin given concurrently twice daily. As a result of concurrent administration this therapy has given better results according to some studies in comparison to sequential variants. However, this therapy, as well suffers from the aforementioned increase in antibiotic resistance. Therefore, the aim of this study was to compare concomitant non-bismuth quadruple therapy with a tailored therapy based on antibiotic strain susceptibility testing assuming that eradication rate with tailored therapy will be above 90%.

Inclusion Criteria:

• helicobacter pylori infection

Exclusion Criteria:

• previous unsuccessful eradication treatment, stomach or other malignancy, taking of proton pump inhibitors, H2-antagonists, bismuth or antibiotics (amoxicillin, metronidazole, clarithromycin) in the previous month, significant comorbidities (renal insufficiency, psychiatric disease), denial to participate in the study, history of allergy to proton pump inhibitors or antibiotics, pregnancy and lactation.