Recent insights into catheter-related urinary tract infections.

Urinary tract infections (UTIs) commonly develop in people with urinary catheters. Inserting a catheter can damage the urothelial barrier and trigger the formation of a biofilm on the catheter that allows bacteria direct access to the bladder. Biofilms also protect bacteria from the immune system and reduce antibiotic effectiveness. In addition, a growing literature suggests that the urinary tract harbours bacteria even in people with negative conventional cultures. The urinary microbiome is highly individual. Nevertheless, changes in the urinary microbiome may identify individuals at risk of UTIs and, for example, suggest that a catheter should be replaced more frequently and, in turn, avoid the need for antibiotics. This article outlines the importance of biofilms in the development of catheter-related UTIs and introduces the urinary microbiome.