Howlin R P, Brayford M J, Webb J S, Cooper J J, Aiken S S, Stoodley P
National Institute for Health Research Southampton Respiratory Biomedical Research Unit, Southampton Centre for Biomedical Research, University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom Centre for Biological Sciences, Faculty of Natural and Environmental Sciences and Institute for Life Sciences, University of Southampton, Highfield, Southampton, United Kingdom.
Biocomposites Ltd., Keele Science Park, Keele, Staffordshire, United Kingdom.
Antimicrob Agents Chemother. 2015 Jan;59(1):111-20. doi: 10.1128/AAC.03676-14. Epub 2014 Oct 13.
Periprosthetic infection (PI) causes significant morbidity and mortality after fixation and joint arthroplasty and has been extensively linked to the formation of bacterial biofilms. Poly(methyl methacrylate) (PMMA), as a cement or as beads, is commonly used for antibiotic release to the site of infection but displays variable elution kinetics and also represents a potential nidus for infection, therefore requiring surgical removal once antibiotics have eluted. Absorbable cements have shown improved elution of a wider range of antibiotics and, crucially, complete biodegradation, but limited data exist as to their antimicrobial and antibiofilm efficacy. Synthetic calcium sulfate beads loaded with tobramycin, vancomycin, or vancomycin-tobramycin dual treatment (in a 1:0.24 [wt/wt] ratio) were assessed for their abilities to eradicate planktonic methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis relative to that of PMMA beads. The ability of the calcium sulfate beads to prevent biofilm formation over multiple days and to eradicate preformed biofilms was studied using a combination of viable cell counts, confocal microscopy, and scanning electron microscopy of the bead surface. Biofilm bacteria displayed a greater tolerance to the antibiotics than their planktonic counterparts. Antibiotic-loaded beads were able to kill planktonic cultures of 10(6) CFU/ml, prevent bacterial colonization, and significantly reduce biofilm formation over multiple days. However, established biofilms were harder to eradicate. These data further demonstrate the difficulty in clearing established biofilms; therefore, early preventive measures are key to reducing the risk of PI. Synthetic calcium sulfate loaded with antibiotics has the potential to reduce or eliminate biofilm formation on adjacent periprosthetic tissue and prosthesis material and, thus, to reduce the rates of periprosthetic infection.
假体周围感染（PI）在固定和关节置换术后会导致严重的发病和死亡，并与细菌生物膜的形成密切相关。聚甲基丙烯酸甲酯（PMMA）作为骨水泥或珠子，常用于向感染部位释放抗生素，但洗脱动力学变化不定，并且也是感染的潜在病灶，因此一旦抗生素洗脱就需要手术取出。可吸收骨水泥已显示出能更好地洗脱更广泛的抗生素，并且至关重要的是能完全生物降解，但关于其抗菌和抗生物膜功效的数据有限。评估了负载妥布霉素、万古霉素或万古霉素 - 妥布霉素联合治疗（重量比为1:0.24）的硫酸钙合成珠相对于PMMA珠根除浮游耐甲氧西林金黄色葡萄球菌（MRSA）和表皮葡萄球菌的能力。使用活细胞计数、共聚焦显微镜和珠子表面扫描电子显微镜相结合的方法，研究了硫酸钙珠在数天内预防生物膜形成和根除预先形成的生物膜的能力。生物膜细菌比浮游细菌对抗生素表现出更高的耐受性。负载抗生素的珠子能够杀死10(6) CFU/ml的浮游培养物，防止细菌定植，并在数天内显著减少生物膜形成。然而，已形成的生物膜更难根除。这些数据进一步证明了清除已形成的生物膜的困难；因此，早期预防措施是降低PI风险的关键。负载抗生素的合成硫酸钙有潜力减少或消除假体周围相邻组织和假体材料上的生物膜形成，从而降低假体周围感染的发生率。
