Do Different Sutures with Triclosan Have Different Antimicrobial Activities? A Pharmacodynamic Approach

Abstract

(1) Background: Three antimicrobial absorbable sutures carry different loads of triclosan (TS), triclosan release kinetics and hydrolysis times. The purpose of this in vitro study is to analyse and compare their antimicrobial pharmacodynamics. (2) Methods: Time-kill assays were performed with eight triclosan-susceptible microorganisms common in surgical site infections (SSIs) and a segment of each TS. Microbial concentrations were measured at T0, T4, T8 and T24 hours. Similar non-triclosan sutures (NTS) were used as controls. Microbial concentrations were plotted and analysed with panel analysis. They were predicted over time with a double-exponential model and four parameters fitted to each TS × microorganism combination. (3) Results: The microbial concentration was associated with the triclosan presence, timeslot and microorganism. It was not associated with the suture material. All combinations shared a common pattern with an early steep concentration reduction from baseline to 4–8 hours, followed by a concentration up to a 24-hour plateau in most cases with a mild concentration increase. (4) Conclusions: Microorganisms seem to be predominantly killed by contact or near-contact killing with the suture rather than the triclosan concentration in the culture medium. No significant in vitro antimicrobial pharmacodynamic difference between the three TSs is identified. Triclosan can reduce the suture microbial colonisation and SSI risk.