Catheter-associated bacteriuria. An experimental study.

A bacteriologically-stressed catheterized animal model was developed to evaluate the comparative importance of the intraluminal versus the extraluminal route of catheter-acquired urinary tract infections. This study indicated that in short-term catheterization (less than 7 days), contamination of the drainage spout or accidental disconnection of the drainage tube resulted in bacteriuria within a short time (32-48 hours). If a strict sterile closed drainage system was maintained, the extraluminal route assumed more importance in the development of bacteriuria, however this pathway was considerably slower (72-168 hours). It appeared that catheter-associated bacteriuria results from ascending bacterial colonization within glycocalyx-enclosed biofilm on the inside and/or outside surfaces of the catheter and drainage systems. Development of a biomaterial that inhibits bacterial adherence and does not allow upstream colonization of bacteria on the catheter drainage system would significantly influence the rate of catheter-acquired urinary tract infection.