Colonization-resistant antimicrobial-coated peritoneal dialysis catheters: evaluation in a newly developed rat model of persistent Pseudomonas aeruginosa peritonitis.

OBJECTIVE

Development of a rat model of persistent peritonitis and evaluation of the ability of liposomal ciprofloxacin hydrogel-coated silicone to resist colonization.

DESIGN

A newly developed model of persistent Pseudomonas aeruginosa peritonitis to compare the ability of liposomal ciprofloxacin hydrogel (LCH)-coated silicone versus plain silicone for resistance to bacterial colonization.

ANIMALS

Male Sprague-Dawley rats.

RESULTS

Inoculating the peritoneum of rats with 1 mL 0.5% agar containing 10(6) colony-forming units (cfu)/mL P. aeruginosa in the presence of a plain silicone coupon resulted in persistent peritonitis for at least 7 days. Plain silicone coupons in all 40 rats were colonized (median 2.54 x 10(3) cfu/cm2; range 5.0 x 10(1)-1.0 x 10(6) cfu/cm2) and peritoneal washings were consistently culture-positive. In contrast, the LCH coupons removed after 7 days from the 40 test rats were sterile, as were the peritoneal washings, and there was no evidence of peritonitis. Blood cultures were negative in both groups.

CONCLUSIONS

Liposomal ciprofloxacin hydrogel-coated silicone resists colonization in this rat model of persistent P. aeruginosa peritonitis.