Evaluation of the antimicrobial efficacy of urinary catheters impregnated with antiseptics in an in vitro urinary tract model.
OBJECTIVE
To evaluate the long-term efficacy of urinary Foley catheters (latex and silicone) impregnated with (1) chlorhexidine and silver sulfadiazine (CXS) and (2) chlorhexidine, silver sulfadiazine, and triclosan (CXST) in inhibiting extra-luminal bacterial adherence and to compare their efficacy with that of silver hydrogel latex (SH) and nitrofurazone-treated silicone (NF) catheters.


METHODS
The antimicrobial spectrum of these catheters was evaluated using a zone of inhibition assay. A novel in vitro urinary tract model was developed to study the potential in vivo efficacy of antimicrobial catheters in preventing extraluminal bacterial colonization. The "meatus" was inoculated daily with Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Enterococcus faecalis, Pseudomonas aerginosa, and Candida albicans. The "bladder" portion of the model was cultured daily to determine bacterial growth.


RESULTS
Both CXS and CXST catheters had a broader antimicrobial spectrum than SH and NF catheters. In the in vitro model, CXST latex and silicone catheters exhibited significantly better efficacy (3 to 25days) against uropathogens, compared with CXS (1 to 14 days) and control (0 to 5 days) catheters (P = .01). CXST latex catheters exhibited significantly longer protection against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa, compared with SH catheters (P = .01). CXST silicone catheters resisted colonization with Staphylococcus aureus and Staphylococcus epidermidis for a significantly longer period (23 to 24 days) than did NF catheters (9 to 11 days) (P = .01).


CONCLUSIONS
Catheters impregnated with synergistic combinations of chlorhexidine, silver sulfadiazine, and triclosan exhibited broad-spectrum, long-term resistance against microbial colonization on their outer surfaces.
Gaonkar
Trupti A
TA
Department of Surgery, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA.
Sampath
Lester A
LA
Modak
Shanta M
SM
D000892:Anti-Infective Agents, Urinary / Q000008:administration & dosage* / Q000145:classification; D001419:Bacteria / Q000187:drug effects; D002408:Catheters, Indwelling; D002710:Chlorhexidine / Q000008:administration & dosage / Q000494:pharmacology; D015169:Colony Count, Microbial; D016503:Drug Delivery Systems; D006801:Humans; D066298:In Vitro Techniques; D008954:Models, Biological; D012837:Silver Sulfadiazine / Q000008:administration & dosage / Q000494:pharmacology; D016896:Treatment Outcome; D014260:Triclosan / Q000008:administration & dosage / Q000494:pharmacology; D014481:United States; D014546:Urinary Catheterization / Q000295:instrumentation*
D000892:Anti-Infective Agents, Urinary; D014260:Triclosan; D002710:Chlorhexidine; D012837:Silver Sulfadiazine