多重耐药大肠埃希菌氨基糖苷类修饰酶与Ⅰ类整合酶基因的研究

摘要

Objective To investigate the anminoglycosides modifying enzyme genes and intll gene in Escherichia coli. Methods The susceptibilities of 71 E. coli strains to 4 antibiotics were detected by disk diffusion test which was recommended by NCCLS 2006. The anminoglycosides modifying enzyme genes and intll gene were detected by PCR. Results 47 strains (66.20%)were resistant to gentamicin, 45 strains (63.38%) to levofloxacin, 42 strains (59.15%) to cefotaxime, and 13 strains(18.31%)to ceftazidime. There were 23 (32.39%) multidrug resistant strains in 71 E. coli strains. In 71 strains of E. coli, the positive strains of aac(3)-Ⅱ were 40 strains (56.34%), aac(6')-I were 22 strains (30.99%), ant(3")-I were 14 strains (19.72%), and aac(6')-Ⅱ positive strains were not detected. The total detection rate of anminoglycosides modifying enzyme genes was 74.65%. The positive strains of intll gene was 53 strains(74.65%). There was statistical difference between the positive rate of multidrug resistant and non- multidrug resistant strains. Conclusion There are high detection rates of the anminoglycosides modifying enzyme genes and intll gene in the multidrug resistant E. coli strains isolated from the hospital.%目的 探讨本地区临床分离多重耐药大肠埃希菌(Escherichia coli,E.coli)的氨基糖苷类修饰酶和Ⅰ类整合子基因存在情况.方法 纸片扩散法(K-B法)测定71株大肠埃希菌对常用抗菌药物的耐药性,应用PCR技术对E.coli进行氨基糖苷类修饰酶和Ⅰ类整合酶基因的检测.结果 71株大肠埃希菌对庆大霉素、左氧氟沙星、头孢噻肟、头孢他啶的耐药率分别分为66.20％、63.38％、59.15％、18.31％,其中23株为多重耐药株(32.39％).氨基糖苷类修饰酶基因aac(3)-Ⅱ阳性40株(56.34％),aac(6′)-Ⅰ阳性22株(30.99％),ant(3″)-Ⅰ阳性14株(19.72％),未检出aac(6′)-Ⅱ阳性株,氨基糖苷类修饰酶基因总检出率为74.65％;Ⅰ类整合酶基因(intI1)阳性53株(74.65％).多重耐药与非多重耐药大肠埃希菌中aac(3)-Ⅱ、aac(6')-Ⅰ、总氨基糖苷类修饰酶基因、intI1的阳性率有统计学差异(P＜0.05).结论 本地区多重耐药E.coli的氨基糖苷类修饰酶基因、Ⅰ类整合酶基因携带率高.