[Urinary tract infections].

During the past ten years, new concepts on host-parasite interaction have allowed better understanding of the pathogenesis of urinary tract infections (UTI). In addition, significant progress has been achieved with the development of new methods for differentiating upper and lower UTI. This review is intended to discuss current information about virulence factors of Escherichia coli, host genetic risk markers associated to recurrence and complications, and new diagnostic tools for localizing the anatomic place of urinary tract infections.