In Vivo and In Vitro Antibacterial Efficacy of PDS Plus (Polidioxanone with Triclosan) Suture

Background: This study evaluated the efficacy of polydioxanone suture with and without triclosan against gram-positive and gram-negative bacteria in vitro and in vivo. Methods: Polydioxanone suture with and without triclosan was tested against Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), S. epidermidis, methicillin-resistant S. epidermidis (MRSE), Klebsiella pneumoniae, and Escherichia coli by a zone of inhibition assay. In vivo evaluations were conducted in guinea pigs and mice in which test and control sutures (3-4 cm long) were implanted subcutaneously in the dorsal-lateral regions (control on left, test on right, 3-5 cm apart) through a 20 gauge catheter. Each implantation site was then challenged directly through the catheter with 4 x 105 colony-forming units (CFU) of S. aureus (guinea pigs) or 7 x 106 CFU of E. coli (mice). At 48 h post-implantation, the control and test sutures were explanted, and adherent bacteria were counted. Results: Polydioxanone suture with triclosan demonstrated activity against all test organisms in vitro. The antibacterial activity was maintained until the sutures dissolved after 17 to 23 days when tested against E. coli and S. aureus, respectively. Evaluation in animal models demonstrated a 99.9% reduction in S. aureus and a 90% reduction in E. coli relative to controls. Conclusion: Polydioxanone suture with triclosan had activity in vitro against S. aureus, MRSA, E. coli, S. epidermidis, MRSE, and K. pneumoniae that persisted for as long as three weeks. In animal models, polydioxanone suture with triclosan inhibited in vivo colonization by S. aureus and E. coli.