多重耐药肺炎克雷伯菌氨基糖苷类药物耐药相关基因研究

目的：了解多重耐药肺炎克雷伯菌氨基糖苷类修饰酶基因的存在状况。方法：自2006年1月至2006年10月住院病人标本中分离并筛选出20株多重耐药肺炎克雷伯菌，微量肉汤稀释法检测20种抗菌药物的敏感性；PCR法检测15种氨基糖苷类修饰酶基因。结果：20株多重耐药肺炎克雷伯菌对氨基糖苷类药物庆大霉素、妥布霉素、奈替米星及阿米卡星耐药率分别为75％、80％、65％和60％，其中氨基糖苷类修饰酶aac（3）-Ⅱ基因阳性15株，aac（6’）-I b基因阳性1株，ant（3”）-I基因阳性16株，aph（3’）-I基因阳性3株，ant（2”）-I基因阳性1株。结论：多重耐药肺炎克雷伯菌对氨基糖苷类药物耐药的主要原因是aac（3）-Ⅱ、aac（6’）-I b、ant（3”）-I、aph（3’）-I和ant（2”）-I等5种氨基糖苷类修饰酶基因的存在；从肺炎克雷伯菌中检出aac（6’）-I b-Cr型和aph（3’）-I均为国内首次。

Study on the drug resistance-related aminoglycoside genes from multi-resistant klebsiella pneumoniae

Objective： To understand the existence of genes encoding aminoglycoside modifying enzyme in multi-resistant Klebsiella pneumoniae. Methods： Samples of 20 strains of multi-resistant Klebsiella pneumoniae collected from the patients from January 2006 to October 2006 were isolated and screened out. The sensitivity of 20 antibacterial agents by means of broth induction was detected, and genes of aminoglycoside modifying enzyme by way of polymerase chain reaction were detected. Results： The resistance rates of 20 strains of multi-resistant Klebsiella pneumoniae to aminoglycoside,such as gentamicin, tobramycin, netilmicin and amikacin were 75%, 80%, 65% and 60%, respectively. Of which, 15 strains of aminoglycoside modifying enzyme aac （3＇）-Ⅱ gene positive, 1 strain of aac （6＇）-Ib,16 ones of ant （3”）-I ,3 ones of aph （3＇）-I and 1 strain of ant （2”） were found at the same time. Conculsion： The main reasons of multi-resistant Klebsiella pneumoniae resistance to aminoglycoside are the presence of aminoglycoside modifying enzymes called aac （3）-Ⅱ, aac （6”）-Ib, ant （3”）- I , aph （3＇）- I and ant （2”）- I genes. Genes of aac （6＇）-Ib-Cr and aph （3＇）- I in Klebsiella pneumoniae are both first found and reported in China.