[Epidemiology and pathogenesis of Helicobacter pylori infection]

Since Marshall and Warren reported the first isolation of Helicobacter pylori basic and clinical research on pathogenesis and epidemiology of Helicobacter pylori infection have been tremendous. Childhood is clearly established as the period of major risk for Helicobacter pylori acquisition. The transmission pathways may be several including the oral-oral, the gastro-oral or the fecal-oral transmission route. The colonization of Helicobacter pylori occurs exclusively in the gastric mucosa or in areas of gastric metaplasia especially in the duodenum. Helicobacter pylori possesses several factors to adhere to the epithelial cells and to cause mucosal damage. The acquisition of Helicobacter pylori always induces a chronic gastritis. The development to clinical manifestations (peptic ulcer or gastric cancer) are further dependent on specific bacterial strain virulence factors as well as on host and environment factors. The mechanisms involved in the inflammatory process have been elucidated in great detail and will further be focused and related to specific associated disease development.