OBJECTIVE: To determine: (1) the in-vitro minimum inhibitory concentration of CHG and PI against model PJI-causing organisms and clinical isolates; (2) their impact on biofilm formation; (3) whether there is a synergistic benefit to combining the two solutions; and (4) whether adding the antibiotic vancomycin impacts antiseptic activity.
METHODS: We measured in-vitro growth and biofilm formation of Staphylococcus epidermidis, meticillin-sensitive and meticillin-resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans, as well as recent clinical isolates, in the presence of increasing concentrations of CHG and/or PI. Checkerboard assays were used to measure potential synergy of the solutions together and with vancomycin.
RESULTS: CHG and PI inhibited growth and biofilm formation of all model organisms tested at concentrations of 0.0004% and 0.33% or lower, respectively; highly dilute concentrations paradoxically increased biofilm formation. The solutions did not synergize with one another and acted independently of vancomycin.
CONCLUSIONS: CHG and PI are effective at lower concentrations than typically used, establishing baselines to support further clinical trials aimed at optimizing wound disinfection. There is no synergistic advantage to using both in combination. Vancomycin is effective at inhibiting the growth of S. epidermidis and S. aureus; however, it stimulates P. aeruginosa biofilm production, suggesting in the rare case of P. aeruginosa PJI, it could exacerbate infection.
目的:确定:(1)CHG和PI对引起PJI的模型生物和临床分离株的体外最小抑制浓度;(2)它们对生物膜形成的影响;(3)结合两种溶液是否具有协同作用;(4)添加抗生素万古霉素是否会影响抗菌活性。
方法:我们测量了表皮葡萄球菌的体外生长和生物膜形成,甲氧西林敏感和耐甲氧西林金黄色葡萄球菌,大肠杆菌,铜绿假单胞菌,和白色念珠菌,以及最近的临床分离株,在CHG和/或PI浓度增加的情况下。棋盘测定用于测量溶液一起和与万古霉素的潜在协同作用。
结果:CHG和PI在0.0004%和0.33%或更低的浓度下抑制了所有模型生物的生长和生物膜形成,分别;高度稀释的浓度矛盾地增加了生物膜的形成。溶液彼此没有协同作用并且独立于万古霉素起作用。
结论:CHG和PI在低于通常使用的浓度下有效,建立基线,以支持旨在优化伤口消毒的进一步临床试验。两者组合使用没有协同优势。万古霉素可有效抑制表皮葡萄球菌和金黄色葡萄球菌的生长;然而,它刺激铜绿假单胞菌生物膜的产生,在罕见的铜绿假单胞菌PJI病例中,它可能会加剧感染。