外排泵acra/acrb基因与多药耐药大肠埃希菌关系的探讨

Relationship between efflux pump gene acra/acrb and multidrug-resistant escherichia coli

目的了解大肠埃希菌(ECO)对3类6种常用抗菌药物的耐药性以及外排泵acra/acrb基因在临床分离株中的存在,探讨acra/acrb与大肠埃希菌多药耐药性间的相关性。方法药物敏感试验采用美国临床实验室标准化委员会推荐的纸片扩散法(K-B法)进行6种抗菌药物的药物敏感性检测;PCR技术检测大肠埃希菌携带acra/acrb基因的情况。结果耐药模式中以多药耐药为主占52.11%,其表型以CTX+G+S+CIP+LEV为主,8株,占11.27%;acra/acrb阳性率在多耐药株与双耐药株、单耐药株、全敏感株比较差异均有统计学意义。结论大肠埃希菌对3类6种抗菌药物普遍耐药,并且存在明显的多药耐药和交叉耐药现象;外排泵基因acra/acrb是大肠埃希菌多药耐药的重要原因之一。

OBJECTIVE To investigate the resistant situation to 3 types, 6 antibiotics of local Escherichia, to detect efflux pump gene acra/acrb in Escherichia coli （ECO）, and research on the relationship between multiple drug resistance of E. coli And acra/acrb. METHODS Disk diffusion test：the susceptibility of 71 strains of E. coli to 6 antibiotics were detected by disk diffusion which was recommended by NCCLS. The gene of acra/acrb were determined by PCR. RESULTS Multidrug resistance was the main part of resistant pattern （52. 11%）, and the phenotype standed for CTX＋G＋S＋CIP q-LEV（8 strain, 11. 27%）. Acra/acrb positive rates had statistical difference by chisquare test when multidrug resistant strain compare with other strains. CONCLUSION The resistance to 6 antibiotic of local E. coli is common, and multidrug and cross resistance are obvious; acra and acrb are important reason for multidrug resistance.