铜绿假单胞菌金属酶的检测及分析

Detection and analysis of metallo-β-lactamases in Pseudomonas aeruginosa

目的了解耐碳青霉烯铜绿假单胞菌的金属酶基因携带情况和基因型,同时探讨金属酶筛选的简便方法。方法对来自广州医科大学附属第一医院临床分离的50株耐碳青霉烯铜绿假单胞菌,采用双纸片增效法进行金属酶表型检测、采用PCR法进行金属酶bla_(VIM)和bla_(IMP)基因检测,并对基因进行序列分析。结果亚胺培南、亚胺培南+乙二胺四乙酸(EDTA)双纸片增效法筛选出11株(22.0%)金属酶表型阳性株,经PCR法确证其中9株产金属酶;碳青霉烯耐药株金属酶基因的携带率为18.0%(9/50),其中IMP型占88.9%(8/9),VIM型占11.1%(1/9)。结论耐碳青霉烯铜绿假单胞菌金属酶携带率高,以IMP型为主;亚胺培南和亚胺培南+EDTA双纸片增效法是金属酶表型筛选简便易行的方法。

Objective To investigate the prevalence and genotypes of metallo- β-lactamases in P. aeruginosa isolated from our hospital, and explore the convenient methods for screening of metallo- β-lactamases. Methods Fifty carbapenemresistant P. aeruginosa strains isolated from The First Affiliated Hospital of Guangzhou Medical University were collected.The double disc synergy method was used for phenotypic detection of metallo- β-lactamases, and PCR was applied for detection of the blaIMP and blaVIM genes. The PCR product was analyzed by DNA sequencing. Results Eleven strains（22.0%）were detected positive for metallo- β- lactamases by the imipenem- imipenem ＋ EDTA double disc synergy method. The production of metallo-β-lactamases was confirmed in 9 strains（18.0%） by PCR, with 88.9%（8 / 9） of blaIMP genes and 11.1%（1 / 9） of blaVIM genes. Conclusion The positive rate for carbapenemase production was high in P. aeruginosa strains isolated from our hospital, and IMP was the major genotype. The imipenem-imipenem＋EDTA double disc synergy method was a easy and convenient method for screening of carbapenemases.