Coating urinary catheters with E. coli inhibits colonization by Enterococcus

NEW YORK (Reuters Health) – Inoculating urinary catheters with Escherichia coli reduces the subsequent growth of Enterococcus faecalis, researchers in Houston report. This approach may help reduce symptomatic urinary tract infections in patients who must be catheterized for extended periods of time.

Dr. John I. Thornby, of Baylor College of Medicine, and colleagues cite recent findings that inoculating the bladder with a nonpathogenic strain of E. coli can prevent symptomatic infection, a process known as bacterial interference. The problem, they note, is that establishing long-term colonization is difficult, with the E. coli frequently clearing spontaneously.

Using a strain of E. coli known to persist in the urinary tract without causing symptoms, Dr. Thornby's group incubated pieces of latex Foley catheters for 24 hours in the presence of 100,000 colony-forming units (CFU)/mL. The catheter pieces were then placed in broth containing E. faecalis 10,000 CFU/mL for 30 minutes, and then incubated in sterile urine for 24 hours. The CFUs of each organism were then quantitated.

Catheter pieces incubated in the presence of E. coli significantly reduced the colonization of E. faecalis by more than 10-fold compared with uncoated catheter pieces (p = 0.016). Further experiments showed that Enterococcus did not replace E. coli on the catheter surface.

The authors suggest that E. coli may produce biosurfactants or other microbial products that slow the deposition rates and decrease adherence of E. faecalis cells. They hope that using such catheters in vivo will prevent the need for antibiotic treatments, thus stopping the development of resistant urinary flora, cutting the incidence of adverse reactions, and averting supra-infections with such organisms as Clostridium difficile.

0 תגובות

השאירו תגובה

רוצה להצטרף לדיון?
תרגישו חופשי לתרום!

כתיבת תגובה

מידע נוסף לעיונך

כתבות בנושאים דומים