肺炎克雷伯菌氨基糖苷类修饰酶耐药基因研究

目的检测肺炎克雷伯菌氨基糖苷类修饰酶的分布,探讨肺炎克雷伯菌对氨基糖苷类药物耐药机制。方法收集中南大学湘雅医院2009年1月至2009年7月间非重复肺炎克雷伯菌96株,所有菌株采用法国梅里埃公司的全自动微生物鉴定系统VITEK -2的革兰阴性菌GN卡鉴定和AST GN-13卡进行药敏分析。采用PCR法对氨基糖苷类修饰酶基因aac(3)-Ⅰ、aac(6′)-Ⅰb、ant(3″)-Ⅰ、aph(3′)-Ⅵa进行检测。结果经PCR扩增及测序分析,96株肺炎克雷伯菌中有18.8%的菌株携带aac(3)-Ⅰ基因（18/96）、57.3%的菌株携带aac(6′)-Ⅰb基因（55/96）、3.1%的菌株携带ant(3″)-Ⅰ基因（3/96）,未扩增出aph(3′)-Ⅵ基因。结论在湖南地区发现aac(3)-Ⅰ、aac(6′)-Ⅰb、ant(3″)-Ⅰ型氨基糖苷类修饰酶基因,氨基糖苷类修饰酶基因以aac(6′)-Ⅰb为主。是肺炎克雷伯菌对氨基糖苷类药物高水平耐药的主要机制之一。

Study on drug resistance genes of aminoglycosides modifying enzymes among Klebsiella pneumoniae

ObjectiveTo investigate the drug resistance and detect aminoglycosides modifying enzymes in Klebsiella pneumonia from Xiangya Hospital of Central South University. Methods96 non-repetitive clinical isolates of Klebsiella pneumoniae strains were collected from Xiangya hospitals of Central South University in January 2009 to July 2009. aminoglycosides modifying enzymes（aac(3)-Ⅰ、aac(6′)-Ⅰb、ant(3″)-Ⅰ、 aph(3′)-Ⅵa）was detected by PCR.. ResultAmong aminoglycosides modifying enzymes isolates of Klebsiella pneumoniae through PCR amplification,aac(3)-Ⅰ、aac(6′)-Ⅰb and ant(3″)-Ⅰ isolates accounted for 18.8%、57.3% and 3.1% respectively.aac(6′)-Ⅰb is the most common genotype.The prevalence of aac(6′)-Ⅰb in ciprofloxacin-resistant and susceptible Isolates were 79.1%（19/24）and 50%（36/72）. Through Chi-Square Tests , the difference was statistically significant（χ²=6.26,P<0.05）. Conclusionaac(3)-Ⅰ、aac(6′)-Ⅰb、ant(3″)-Ⅰ aminoglycosides modifying enzymes had emerged for the first time in Human Province , aac(6′)-Ⅰb is the most common genotype. It may play an important role in Aminoglycosides resistance.