耐亚胺培南铜绿假单胞菌的金属β-内酰胺酶检测

Detection of metallo-β-lactamase in imipenem-resistant Pseudomonas aeruginosa

目的了解耐亚胺培南铜绿假单胞菌产金属β-内酰胺酶(MBL)的分离率以及编码MBL的基因型别。方法采用双纸片协同试验结合增强试验对116株耐亚胺培南铜绿假单胞菌进行MBL的表型检测,同时采用多重PCR及普通PCR进行MBL的编码基因(包括VIM型,IMP型,SPM型,GIM型,NDM型,SIM型,DIM型,AIM型)检测。结果116株耐亚胺培南铜绿单胞菌中筛选出7株(6%)MBL表型阳性的菌株,用分子生物学的方法也检测出7株金属酶基因阳性的菌株(6%),其中VIM基因阳性的有2株(1.7%),IMP基因阳性的有5株(4.3%),其他基因型均阴性;经过测序和比对分析发现2株菌携带的MBL基因型为VIM-2,5株菌所携带的MBL基因型为IMP-9。结论此次检测铜绿假单胞菌金属β-内酰胺酶的基因型以IMP-9型和VIM-2型流行为主,尚未发现其他型别的基因型。

Objective To understand the isolation rate and genotypes of metallo - β - lactamase（MBL） in imipenem - resisfant Pseudomonas aeruginosa in the First affiliated hospital of Guangzhou medical university. Methods The double - disk synergy test and the double - disk potentiation screen test were used to detect MBL phenotypes in 116 imipenem - resistant P. aerugino- sa strains, and MBL genotypes including VIM - type, IMP - type, SPM - type, GIM - type, NDM - type, SIM - type, DIM - type and AIM - type were detected by multiplex PCR amplication test and ordinary PCR amplication test. Results Of the 1 16 imipenem- resistant P. aeruginosa strains, 7 strains were found positive MBL, 2 of 7 strains were positive VIM -type MBL （ 1.7% ） and 5 of 7 strains were positive IPM - type MBL（4.3% ）, and the other MBL genotypes were not detected. The se- quence analysis revealed that the 2 strains carried blavlM-2 and the 5 strains harbored blalMP-9. Conclusion The genetypes of MBL produced by imipenem -resistance Pseudomonas aeruginosa were mainly blaIMp_9 and blaVIM-2 in the First affiliated hospital of Guanghzou medical university, the other MBL genetypes were not found.