Helicobacter py roli, by its presence in the human digestive system, can lead to a number of pathological changes. In the course of development and worsening of the abnormalities, a number of diseases may appear that pose a direct threat to human health and life, including gastric ulcer cancer and MALT lymphoma outside the gastrointestinal tract. Infection with the bacteria most often occurs in childhood, when the first pathological changes in the mucosa are already visible.