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 × 10 3 cfu/cm 2 ; range 5.0 × 10 1 – 1.0 × 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.