亚抑菌浓度头孢西丁体外诱导大肠埃希菌耐药转移

目的:探讨亚浓度头孢西丁对产ESBL大肠埃希菌耐药质粒接合转移率的影响。方法:分析不同亚抑菌浓度的头孢西丁(0、1、0.5、0.25、0.125μg/ml)分别在不同时间(0、2、4、6、8、10h)对产ESBL大肠埃希菌诱导后,再与受体菌接合4h后观察耐药质粒的接合转移率。结果:产ESBL大肠埃希菌耐药质粒在0.25μg/ml头孢西丁诱导4h后的接合转移率最高,1μg/ml可降低接合转移率,经药物诱导后的各接合子MIC值均有所增高。结论:临床应该合理足量的使用抗生素,以防止耐药性的增强和耐药质粒的播散。

Subinhibitory Concentration of Cefoxitin Induced Resistant Transfer Isolates of ESBLs-producing Strains of Escherichia Coli in Vitro

Objective:To investigation influence of subinhibitory concentration of cefoxitin induced resistant plasmid conjugation transfer isolates of ESBLs-producing strains of Escherichia coli in vitro.Methods:To analyze the changes of transfer frequency(tansconjugants/recipient) in the presence of different subinhibitory concentrations of cefoxitin(0,1,0.5,0.25,0.125μg/ml)and different time(2h,4h,6h,8h,10h) in vitro.Plasmid conjugation was performed by broth mating method.Results:The highest rate of resistant plasmid conjugation transfer is 0.25μg/ml cefoxitin induced 4 hours,1μg/ml cefoxitin could decrease the rate,the MIC of all conjugants would increase after medicine induced.Conclusion:Antibiotic should reasonable and sufficient to be used in clinic,to prevent the increase of drug-resistantance and the dissimination of drug resistant gene.