Innate immunity of the urothelium: A new step in decoding pathogenesis and improving therapeutic strategy for recurrent urinary tract infections in children

Regulation of immune and inflammatory processes of the body is necessary to limit the pathogenic process induced by uropathogenic E. coli in the bladder and kidneys while limiting damage to epithelial barriers. This review presents modern ideas about the features of innate immunity of the epithelium of the urinary system (urothelium) as the first barrier to infectious agents. As the nature of immune responses in the urinary tract becomes clearer, this knowledge can be used to develop new and effective strategies for the treatment and/or prevention of urinary tract infection. Some of these strategies are aimed at enhancing innate immune responses, and some at adaptive immune responses. However, the effectiveness of these strategies is based almost exclusively on data obtained from experimental mouse models. Overall, these recent results continue to better illuminate the processes in the body that increase susceptibility to urinary tract infections and their severity. In addition to the isolation and characterization of the uropathogen, a key requirement in the diagnosis of urinary tract infection may be to determine the nature of a defect in the local urinary tract immune system. This information can eventually serve as a basis for the development of new possible therapeutic approaches to the treatment of acute and recurrent urinary tract infections and allow in the future to adapt treatment methods for individual patients in such a way that they are pathogenetically justified, as individualized as possible and reduce the risks of recurrence and chronization of urinary tract infections.

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