台州地区产金属β-内酰胺酶的铜绿假单胞菌的检测及其耐药性分析

Detection and drug resistance analysis of Pseudomonas aeruginosa producing metallo-β-lactamase in Taizhou area

目的分析台州地区耐碳青霉烯类铜绿假单胞菌产金属β-内酰胺酶(MBL)的情况及其对临床常用抗菌药物的耐药性,为临床抗感染治疗提供依据。方法采用K-B法进行体外药敏试验,筛选出耐碳青霉烯类的铜绿假单胞菌株;采用E-test法检测耐碳青霉烯类铜绿假单胞菌是否产MBL;采用PCR及DNA测序技术检测IMP、VIM、SIM-1、GIM-1和SPM-1这5种主要的MBL基因型。结果在临床分离的180株铜绿假单胞菌中耐碳青霉烯类的有51株(28.3%),其中产MBL的有13株(25.5%);13株产酶菌株中IMP-1型阳性8株,VIM-2型阳性5株,未检测出SIM、GIM-1和SPM-1型,且产MBL的铜绿假单胞菌对多种抗菌药物耐药且耐药率显著高于非产酶菌株(P<0.05)。结论 本地区耐碳青霉烯类的铜绿假单胞菌检出率较高,多重耐药现象较严重,产MBL是铜绿假单胞菌对碳青霉烯类药物耐药的主要原因之一,且台州地区耐碳青霉烯类的铜绿假单胞菌以产IMP-1型和VIM-2型为主,临床应加强对产酶株的检测和监控,合理选用抗菌药物。

Objective To analysis carbapenem resistant Pseudomonas aeruginosa producing metallo-β- lactamase（MBL） in Taizhou area and drug resistance to clinical antibacterial agents, to provide evidences for clinical anti-infection treatment. Methods K-B method was used for antimicrobial susceptibility testing, and the carbapenem resistant Pseudomonas aeruginosa strains were screened. E-test was used to detect metallo-β-lactamase produced by carbapenem resistant Pseudomonas aeruginosa. PCR and DNA sequencing technology were used for detecting five main metallo-β-lactamase genotypes, including IMP, VIM, SIM-1, GIM-1 and SPM-1. Results Carbapenems resistant Pseudomonas aeruginosa were 51 among 180 isolates, accounting for 28.3%, among them 13 isolates were producing metallo-β-lactamase, accounting for 25.5%. There were 8 isolates IMP-1 type MBL positive and 5 isolates VIM- 2 type MBL positive among enzyme producing isolates, but SIM, GIM-1 and SPM-1 type MBL were not detected. Pseudomonas aeruginosa producing metallo-β-1actamase was resistant to many antimicrobial agents and the resistant rate was significantly higher than that of non-producing enzyme isolates （P〈0.05）. Conclusion The detection rate of carbapenem resistant Pseudomonas aeruginosa in Taizhou area was high, and the multidrug resistance phenomenon was serious. Producing metallo-β-lactamase is one of main reasons for Pseudomonas aeruginosa resistant to carbapenem, and IMP-1 type and VIM-2 type metallo-β-lactamase are predominant in Taizhou. Clinical doctors should strengthen clinical detection and monitor the enzyme producing strains, rationally use antibacterial agents. Key words