Jan Bureš, Marcela Kopáčová, Stanislav Rejchrt
Helicobacter pylori infection belongs to the most common infections worldwide, it is estimated that 60 - 80 % of population is infected. The prevalence is lower in developed countries (15 - 40 %) and high in developing countries (80 - 95 %). Helicobacter pylori is an obligatory pathogen for humans, chronic colonisation of the stomach by this bacteria always causes chronic gastritis. Despite the fact that some types of chronic gastritis present with a typical endoscopic pattern, the diagnosis of chronic gastritis must be based only on the histology. Pepsinogen I/II ratio is an important laboratory marker. Low values of this ratio are associated with chronic atrophic pangastritis and risk of gastric cancer. Nowadays most authors agree that chronic gastritis is asymptomatic and is not the cause of functional dyspepsia. Eradication of Helicobacter pylori is indicated in chronic atrophic pangastritis with a higher risk of malignant transformation (intestinal metaplasia, dysplasia).