产金属β-内酰胺酶铜绿假单胞菌的基因检测及耐药性研究

Genotypes and resistance of metallo-beta-lactamase-producing Pseudomonas aeruginosa

目的 研究本地区铜绿假单胞菌临床分离株中产金属 β -内酰胺酶流行株的主要基因型和耐药性。 方法 用纸片扩散法进行抗生素协同敏感试验 ,检测产金属 β -内酰胺酶的铜绿假单胞菌 ,用琼脂稀释法检测其最低抑菌浓度 (MIC) ,分别用金属酶IMP - 1,IMP - 2 ,VIM - 1和VIM - 2引物进行聚合酶链反应 (PCR)并对扩增产物进行序列分析。结果 在 82株耐亚胺培南铜绿假单胞菌中 ,抗生素协同敏感试验阳性 7株 ,PCR检测金属 β -内酰胺酶阳性株也为这 7株 ,且基因型均为VIM - 2型。产酶株对亚胺培南、头孢噻肟、头孢他啶、哌拉西林 /他唑巴坦等常用抗铜绿假单胞菌 β -内酰胺类抗生素不敏感 ,对氨曲南较为敏感。结论 本地区铜绿假单胞菌所产金属 β-内酰胺酶为VIM - 2型 ,且产酶株耐药性强 ,应注意对其进行临床检测和监控。

To investigate the genotypical characteristics and sensitivity of metallo beta lactamases in clinical isolates of Pseudomonas aeruginosa The clinical isolates of metallo beta lactamase producing Pseudomonas aeruginosa were confirmed by synergic sensitivity tests and the MIC were determined by agar dilution method.PCR were performed using primers specific for bla IMP 1 ,bla IMP 2 ,bla VIM 1 and bla VIM 2 respectively,and the PCR products were purified and sequenced If was found that metallo beta lactamase producing strains were unsensitive to ceftazidime,cefotaxime,imipenem and piperacillin/tazobactam PCR experiment gave blaVIM positive results for all the strains,and the PCR products were identified with VIM 2 by DNA sequencing If concludes that VIM 2 is the genotype of metallo beta lactamases in clinical isolates of Pseudomonas aeruginosa in this area and the emergence of resistant Pseudomonas aeruginosa will continue to be a serious problem