大肠埃希菌体外对氟喹诺酮类药物交叉耐药的研究  

A Study of Escherichia coli Cross-resistance to Fluoroquinolones in Vitro

作　　者：荆鹏伟[1] 罗予[2] 

机构地区：[1]河南中医学院第一附属医院检验科,河南郑州450000 [2]河南省(郑州大学)医药科学研究院,河南郑州450052

出　　处：《河南预防医学杂志》2009年第1期14-16,21,共4页Henan Journal of Preventive Medicine

基　　金：河南省教育厅自然科学基础研究计划项目(200551288002)

摘　　要：目的探讨大肠埃希菌在体外对氟喹诺酮类药物的交叉耐药性。方法采用多步诱导法,对32株临床分离的氟喹诺酮类敏感大肠埃希菌分别进行环丙沙星、左氧氟沙星、加替沙星的诱导性耐药试验;用琼脂稀释法测定药物敏感性。结果22株大肠埃希菌诱导出稳定的高耐氟喹诺酮菌株;与原株比较,耐药株的MIC分别增加了32-3 000倍,三种氟喹诺酮药物诱导的耐药株对三种药物存在交叉耐药性;进行测序的1株诱导高度耐药菌株的gyrA发生Ser83→Leu、Asp87→Asn,parC发生ser80→Ile的氨基酸替换,而测序的一株敏感菌株未发现氨基酸改变。结论在低浓度抗菌药物的长期压力下,可诱导大肠埃希菌产生对氟喹诺酮类药物的获得性耐药,氟喹诺酮药物之间存在交叉耐药性。Objective To study the cross-resistance of Escherichia coli to ciprofloxacin or levofloxacin or gatifloxacin.Methods The experiments on induced resistance to ciprofloxacin or levofloxacin or gatifloxacin were performed by multiple-step method,in 32 Escherichia coli that sensitived to fluoroquinolones from clinic respectively.The susceptibility of the induced strains resistant to fluoroquinolones was measured by determining the MIC using agar dilution method.Results The strains highly resistant to fluoroquinolone were obtained from twenty two tested strains of Escherichia coli,the MICs of these laboratory resistant strains were with 32 to 3000 fold increase,respectively,when compared with parent strains.An induced highlyresistant strains examined carried two gyrA mutations affecting residues serine 83 and aspartate 87,and one parC mutation of serine 80 to isoleucine.No mutation was found in a susceptible isolate.Conclusion The results of in vitro experiments show that acquired resistance could be occurred when exposing them to low level of some fluoroquinolones for long term.There are cross-resistance among various fluoroquinolones.

关 键 词：大肠埃希菌 氟喹诺酮类药物 诱导性耐药 交叉耐药 

分 类 号：R978.1[医药卫生—药品]