3种抗菌药物对骨科内置物术后感染病原菌的体外抗菌活性观察

Observation on in vitro antibacterial activity of three kinds of antimicrobial agents against pathogens for infection after orthopedic implantation

目的观察利福平(RIF)联合左氧氟沙星(LVX)、万古霉素(VAN)用于骨科内置物术后感染耐甲氧西林金黄色葡萄球菌(MRSA)、凝固酶阴性葡萄球菌(MRCNS)的体外抗菌活性效果,为临床用药提供参考依据。方法分析2010年7月-2013年7月行骨科内植物术后发生感染的住院患者临床资料,选取MRSA和MRCNS感染患者各15例,研究的抗菌药物为利福平、左氧氟沙星、万古霉素,通过肉汤微稀释法确定3种抗菌药物的最低抑菌浓度,然后通过棋盘法分别对利福平联合左氧氟沙星与利福平联合万古霉素对于MRSA、MRCNS的相加、协同、无效以及拮抗效果进行判断,并用时间杀菌曲线法对整个培养观察时间内有关抗菌剂联合用药的效果进行分析。结果对于菌株中的残余菌则显示相加效应,利福平联合左氧氟沙星有9例占30.00%,利福平联合万古霉素有10例占33.33%;所有菌株在24h内培养中利福平联合左氧氟沙星与利福平联合万古霉素均显示协同效应为100.00%;与单独使用万古霉素和利福平相比,联合用药能显著减少细菌的生长率16.70%。结论利福平联合其他抗菌药物对骨科内置物术后感染常见病原菌具有良好的体外抗菌活性,是治疗细菌生物被膜感染的比较理想的药物,值得在临床上推广。

OBJECTIVE To observe the in vitro antibacterial activity of rifampicin （RIF） in combination with other antibiotics （levofloxacin （LVX） ,vancomycin （VAN）） against methicillin‐resistant Staphylococcus aurous （MR‐SA） and coagulase negative Staphylococci （MRCNS） in infection after orthopedic implantation ,so as to provide reference for clinical medication .METHODS The clinical data of inpatients who had infection after orthopedic im‐plantation during Jul .2010 to Jul .2013 were analyzed .MRSA and MRCNS of each 15 cases were selected ,and the antimicrobial agents for study were RIF ,LVX and VAN .The minimum inhibitory concentrations of these three antimicrobial agents were determined by broth microdilution ,then the chessboard method was used to judge the effect of addition ,synergism ,inefficiency or antagonism for RIF＋LVX and RIF＋VAN on MRSA and MRC‐NS ,and the time‐kill curve method was used to analyze the effect of the combination therapy throughout the cul‐ture and observation period .RESULTS The presence of residual strains indicated an additional effect which was showed in 9 cases （30 .00% ） for RIF＋ LVX and in 10 cases （33 .33% ） for RIF＋ VAN .In the 24 h culture all strains showed a synergistic effect for both RIF＋LVX and RIF＋VAN （100 .00% ） .Compared with single VAN and RIF , the combination therapy significantly reduced the bacterial growth rate which was 16 .7% . CONCLUSION RIF in combination with other antibiotics achieves good in vitro antibacterial activity against com‐mon pathogens in infection after orthopedic implantation ,which is an ideal treatment for bacterial biofilm infection and worthy to be popularized in clinical practice .