[Pathogenetic importance of helicobacter pylori infection].

H. pylori are etiological factor of human acute and chronic gastritis. Depending on pathogenic factors of microorganism and polymorphism of human genes, chronic gastritis can be a cause for ulcerative enteritis of the duodenum or stomach, gastric adenocarcinoma and MALT-lymphoma development. We revealed genetic features of bacteria, determined the intensity of inflammation, such as pathogenic factors--cag, plastic region of the genome and adhesin coding genes. Epigenetic changes, for example the methylation of E-cadherin gene associated with H pylori, are crucial for carcinogenesis. Thereby, predisposition of chronic gastritis associated with H. pylori to ulcerative enteritis of the duodenum, ulcerative stomach disease or gastric adenocarcinoma depends on topography, the intensity of inflammation and changes of acid production in the stomach.