[Virulence factors of uropathogens].

In contrast to many commensal bacteria, uropathogens are equipped with many virulence-associated factors that facilitate infection of different areas of the urinary tract. Different extra- and intracellular bacterial lifestyles result in acute or recurrent urinary tract infection. Adhesins promote adhesion or invasion as well as biofilm formation. Flagella do not only allow ascension from the urethra to the bladder and even further to the kidneys, but can also function as adhesins and invasins. In later stages of an infection, toxins may destroy host cells, thus protecting against the host response or releasing nutrients. Extracellular polysaccharides, capsules, and the O-antigen protect bacteria against the host immune system. Furthermore, uropathogens may also directly inhibit the mucosal inflammatory response. Specific metabolic traits promote fitness, growth and survival in the urinary tract.