铜绿假单胞菌获得性金属β-内酰胺酶及其相关基因研究

Study on acquired metallo-β-lactamases and its related genes in Pseudomonas aeruginosa

目的了解该院铜绿假单胞菌(Pae)金属酶的产生及其相关基因携带情况。方法采用多种方法进行Pae金属酶初筛、确证试验,并检测4种金属酶基因。结果产金属酶菌株初筛阳性率为53.5%,用头孢他啶(CAZ)/乙二胺四乙酸(EDTA)、CAZ/2-巯基丙酸(2-MPA)、亚胺培南(IMP)/EDTA、IMP/2-MPA检测阳性率分别为13.95%、15.12%、17.44%、18.60%。PCR扩增结果仅IMP-1出现阳性,阳性率达16.28%,其余3种金属酶基因均为阴性。结论不同方法对金属酶检测结果不尽相同;携带IMP-1金属酶基因是该院Pae耐碳青霉烯类等多种药物的主要原因。

Objective To investigate the production of metallo-β-lactamases and its related genes in Pseudomonas aeruginosa.Methods Firstly,we screened MBLs by K-B method.Then we validated the results by CAZ and IMP disk with its corresponding inhibitors.Finally,we amplified four different MBLs genes by PCR.Results Among total 86 strains of Pseudomonas aeruginosa,about 53.5% strains showed resistance to CAZ or IMP.When validated the MBLs by two different disks with inhibitors,the positive rate varied from 13.95% to 18.60%.Among the four kind of detected MBLs genes,only IMP-1 showed positive amplification whose rate was 16.28%.Conclusion We got different results when applied different methods to detect metallo-β-lactamases.The most reasons why Pseudomonas aeruginosa isolated in our hospital show resistant to carbanpenems and other kinds of antibiotics was IMP-1 gene.