Abstract
A significant increase in H. pylori resistance to clarithromycin and metronidazole has been proven in both children and adults. Clarithromycin with resistance over 20 % and metronidazole with resistance over 40 % are not recommended for treating H. pylori infection.
Preferred treatment regimens were designed to reflect the current situation. The classical regimen PPI + AMO + CLA (MET) can be used in cases where the resistance against CLA and MET is lower than stated above.
In the opposite case, a combination of PPI + AMO + levofloxacin (or rifabutin, or furazolidone) must be used. In many countries, this regimen is already the first-choice treatment.
The 4-combination with bismuth is suitable in case of 3-combination treatment failure, or in patients allergic to penicillin.