肠球菌对氟喹诺酮类药物的敏感性及其主动外排机制的研究  

Fluoroquinolone resistance and active drug efflux in Enterococci

作　　者：王文[1] 张玉英[2] 李刚[2] 赵梅[2] 贾伟[2] 

机构地区：[1]宁夏医科大学检验学院,银川750004 [2]宁夏医科大学总医院医学实验中心

出　　处：《中华检验医学杂志》2014年第4期298-301,共4页Chinese Journal of Laboratory Medicine

基　　金：宁夏科技攻关项目资助课题（2008）

摘　　要：目的 研究主动外排泵抑制剂利血平对氟喹诺酮类药物抗肠球菌活性的影响,以及外排泵基因emeA的存在与耐药的相关性,以探讨主动外排作用在肠球菌耐药中所起的作用.方法 采用全自动微生物分析仪（Vitek-2 Compact）将临床分离的100株肠球菌鉴定到种,采用K-B琼脂纸片扩散法进行药物敏感试验,应用琼脂稀释法检测3种氟喹诺酮类药物（环丙沙星、加替沙星、左氧氟沙星）对肠球菌的MIC,同时检测在加入利血平后3种药物MIC的变化情况,用PCR检测编码外排泵的基因emeA在100株肠球菌属细菌中的分布,采用X2检验进行统计学分析.结果 应用利血平后,肠球菌对3种氟喹诺酮类药物的耐药率都减低：环丙沙星耐药率从42％ （42/100）降至28％（28/100）,加替沙星耐药率从30％（30/100）降至17％（17/100）,左氧氟沙星耐药率从33％（33/100）降至23％（23/100）;100株肠球菌属细菌中emeA基因的阳性率为55％,其中62株粪肠球菌中阳性者45株（72.6％）,38株屎肠球菌中阳性者10株（26.3％）;环丙沙星、加替沙星、左氧氟沙星耐药株中emeA基因的阳性率依次为73.8％ （31/42）、76.7％（23/30）、75.8％（25/33）,敏感株中emeA基因的阳性率依次为41.4％（24/58）、45.7％（32/70）、44.8％（30/67）;外排泵基因emeA在耐药株中的阳性率高于敏感株,差异有统计学意义（x2=13.02,8.13,8.57,P均＜0.005）.结论 利血平在体外可以抑制肠球菌对3种氟喹诺酮类药物的主动外排作用,降低肠球菌的MIC值.肠球菌多重耐药外排基因emeA的存在与肠球菌属对抗菌药物的耐药具有相关性.Objective To investigate the effect of reserpine,an efflux pumps inhibitor,on the activities of fluoroquinolones （FQNs） against Enterococci,and the distribution of efflux pump genes emeA and its correlation with the resistance of Enterococci.To elucidate the relationship between FQN resistance in Enterococci and active efflux.Methods One hundred isolates of enterococci were identified by VITEK microbe automatic system.The antibacterial agent susceptibility tests were performed by the disc diffusion method （K-B） in accordance with the CLSI standards.The minimum inhibitory concentration （MIC） of each FQN was tested by the agar dilution method,and the MIC changes were detected after adding reserpine.The distribution of emeA in 100 isolates of Enterococci was determined by PCR.Thex2 test was used to compare the differences of statistical results.Results After reserpine was used,three-FQN resistance in Enterococci was reduced.Ciprofloxacin,gatifloxacin and levofloxacin resistance was reduced from 42% （42/100） to 28% （28/100）,from 30% （30/100） to 17% （17/100）,and from 33% （33/100） to 23% （23/100）,respectively.The positive rate of emeA gene in 100 strains of Enterococci was 55% （55/100）.There were 45 positive strains（72.6%） in 62 E.faecalis and 10 positive strains （26.4%） in 38 E.faecium.The positive rate of emeA gene in the resistant strains against ciprofloxacin,gatifloxacin and levofloxacin was 73.8% （31/42）,76.7% （23/30）,75.8% （25/33）,respectively,and the positive rate of emeA gene in the susceptible strains against above 3 antibacterials were 41.4% （24/58）,45.7% （32/70）,44.8% （30/67）.Efflux pump genes emeA in resistant strains is higher than the sensitive strains,with the statistically significant difference（x2 =13.02,8.13 and 8.57,P 〈 0.005）.Conclusions Reserpine could inhibit the active efflux of in FON Enterococci and reduce the MIC for drug-resistant strains in vitro.Multidrug-resistant efflux pump gene emeA was relevant to antimicrob

关 键 词：肠球菌属 利血平 细菌蛋白质类 

分 类 号：R978.19[医药卫生—药品]