[Pathogenetic aspects of chronic urinary tract infections].

Infections of the urinary tract belong to the most frequent bacterially caused diseases. Strains of bacteria which are able to evoke an infection of the urinary tract distinguish themselves by particular properties. Hereby the existence of O- and K-antigens, the demonstration of adhesins (F-antigens), the ability of the formation of haemolysin and production of colicin V (aerobactin), the serum resistance as well the plasmid profile an important role is ascribed. The ability of uropathogenic bacteria to the adhesion to the epithelial cells of the urinary tract is significant for the development and the course of a disease. A connection is to be established between the rate of bacterial attachment of the epithelial cells and the activity of a pyelonephritis. The defence of an infection of the urinary tract takes place above all in the local area, in which cases among others the phenomenon of the antibody coated bacteria and disturbances of the formation of the secretory IgA are of interest. Various pathogenetic aspects of chronic infections of the urinary tract are discussed on the basis of reports from literature and findings of own investigations.