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/cm(2); range 5.0 x 10(1) - 1.0 x 10(6) Cfu/cm(2)) 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.