泛耐铜绿假单胞菌氨基糖苷类药物产酶耐药机制的研究

Study on mechanisms of aminoglycoside enzyme-producing and drug resistance in pan-drug resistant Pseudomonas aeruginosa

目的:了解我院临床分离泛耐铜绿假单胞菌(PDRPA)16S rRNA甲基化酶基因、氨基糖苷类药物修饰酶基因存在状况,探讨PDRPA氨基糖苷类耐药机制。方法:GNS-448药敏卡及K-B法测定抗菌药物的敏感性,聚合酶链反应(PCR)检测氨基糖苷类修饰酶基因、16S rRNA甲基化酶基因。结果:22株PDRPA对20种常用抗菌药物耐药,16S rRNA甲基化酶rmtB阳性1株(4.5%);氨基糖苷类修饰酶aac(6′)-Ⅰb阳性4株(18.2%),ant(3″)-Ⅰ阳性12株(54.5%),ant(2″)-Ⅰ阳性8株(36.4%),其他基因均阴性。共18株检出氨基糖苷类修饰酶基因。结论:PDRPA氨基糖苷类耐药为多重耐药机制,我院PDRPA氨基糖苷类耐药机制主要与氨基糖苷类修饰酶基因相关。

Objective：To investigate the status of the 16SrRNA methylases gene and aminoglycoside-modifying en-zyme gene in pan-drug resistant Pseudomonas aeruginosa（PDRPA） isolated from clinic,and further understand the resistant mechanisms of aminoglycoside drug.Methods：GNS-448 and K-B test was performed to detect the susceptibility of 19 kinds of antimicrobial agents against 22 strains of PDRPA.16SrRNA methylase genes and aminoglycoside-modifying enzyme genes were detected by polymerase chain reaction（PCR） and verified by DNA sequencer.Results：22 strains of PDRPA were resistant to 20 kinds of antimicrobial agents,the positive rate of rmtB,aac（6′）-Ⅰb,ant（3″）-Ⅰand ant（2″）-Ⅰgenes were 4.5%（1/22）,18.2%（4/22）,54.5%（12/22） and 36.4%（8/22）,respectively.The rest detected genes were negative.The total positive rate of AMEs gene was 81.8%（18/22）.Conclusion：PDRPA is of multi-resistant mechanism.The resistant mechanism of aminoglycoside is mainly related to aminoglycoside-modifying en-zyme gene aac（6′）-Ⅰb,ant（3″）-Ⅰ,ant（2″）-Ⅰin our hospital.