铜绿假单胞菌中氨基糖苷类基因的分布与耐药性研究

Genotyping of aminoglycoside-modifying enzymes in multidrug-resistant Pseudomonas aeruginosa

目的了解医院临床分离的多药耐药铜绿假单胞茵(MDRPA)中氨基糖苷类修饰酶(AMEs)基因存在状况。方法收集临床2010年9-11月分离的铜绿假单胞菌40株进行氨基糖苷类基因检测,采用PCR法检测;统计铜绿假单胞菌的药敏结果,并分析氨基糖苷类基因和耐药性之间的关系。结果 40株铜绿假单胞菌中36株检出耐药基因,检出率为90.0%,PCR扩增出8种氨基糖苷钝化酶基因,大部分菌株均产生氨基糖苷钝化酶,其次为乙酰转移酶(ACC)和核苷转移酶(ANT),acc3Ⅱ、ant6Ⅰ、acc3Ⅳ、acc3Ⅰ、ant(3″)Ⅰ基因的阳性率分别为80.0%、55.0%、25.0%、15.0%及7.5%。结论医院临床分离的多药耐药铜绿假单胞菌中AMEs基因携带率很高,至少存在5种AMEs基因,分别为aac(3)Ⅱ、ant(6)Ⅰ、acc(6′)Ⅰ、acc(3)Ⅰ和ant(3″)Ⅰ。

OBJECTIVE To investigate genotyping of aminoglycoside-modifying enzymes（AMEs） in clinical isolates of multidrug-resistant Pseudomonas aeruginosa（MDRPA）.METHODS A total of 40 strains of MRPA were isolated from hospitalized patients from Sep 2010 to Nov 2010.The genes of aminoglycoside-modifying enzymes were detected by polymerase chain reaction（PCR）;the statistical analysis of drug susceptibility testing results was performed,and the relationship between the genes of AMEs and drug resistance was analyzed.RESULTS Among 40 strains of MPDRPA,the resistance genes were detected in 36 strains with the detection rate of 90.0%,8 genotypes of aminoglycoside passivation genes were amplified with PCR,most of the strains produced aminoglycoside passivation gene,followed by ACC and ANT,the positive rates of acc3Ⅱ,ant6Ⅰ,acc3Ⅳ,acc3Ⅰ,and ant（3″）Ⅰ were 80.0%,55.0%,25.0%,15.0%,and 7.5%,respectively.CONCLUSION The positive rates of AME genes are very high in clinical isolates of MDRPA,there were at least 5 genotypes including aac（3）Ⅱ,ant（6）Ⅰ,acc（6′）Ⅰ,acc（3）Ⅰ,and ant（3″）Ⅰ in AMEs.