Elimination and Prevention of Microbial Colonization of Central Venous Catheters Using Antibiotic Lock Technique and NonLeachable Form of Catheter Surface Incorporated Antibiotic by Gamma Radiation

Abstract

Aim: To test the efficacy of antibiotic lock technique (ALT) and catheter material modification for the eradication and prevention of biofilm formation on central venous catheters (CVCs). Methods: Four resistant clinical isolates, namely Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae and Candida tropicalis were used to study the effectiveness of ALT using levofloxacin (for bacteria) or fluconazole (for candida) to eliminate microbial biofilms. Moreover, with the aid of gamma radiation, gentamicin was covalently attached to the polyurethane catheter and the modified polymeric material was tested for their antimicrobial and anti-adherence properties. Results: The highest and lowest concentrations of levofloxacin tested (1024 and 64 mg/L) eliminated the biofilms of Pseudomonas aeruginosa and Acinetobacter baumannii after 3 and 10 days, respectively and after 1 and 7 days in case of Klebsiella pneumoniae, whereas Candida tropicalis biofilms were eliminated by fluconazole after 3 and 10 days. The modified polymeric material acquired antibacterial and anti-adherence properties. Conclusion: The results suggest that ALT and catheter modification could be effective for eradicating and preventing biofilm formation on CVCs.