The development of bacterial biofilms on indwelling urethral catheters

The biofilm mode of growth has been implicated in the majority of human bac terial infections. In the urinary tract, notable biofilm-associated infecti ons include prostatitis, chronic cystitis, struvite urolithiasis, and cathe ter-associated infections. Biofilms protect the causative organisms from ho st defences and antimicrobial therapy. Biofilm formation has traditionally been considered to result from adhesion and capsule formation by adherent m icroorganisms. Recent work has shown that a large number of genes are activ ated during this process, some of which have been associated with twitching motility, quorum sensing, and slow growth. In this paper, we review some o f the recent work on biofilm biology and highlight its role in urinary trac t infections, particularly those associated with urinary catheters.