耐亚胺培南铜绿假单胞菌及其产金属酶的相关基因blaVIM-2研究

摘要

Objective To understand Imipenem-resistant Pseudomonas aeruginosa(IPMRPa) and its drug-resistance, study the metallo-P-lactamase and the influence of relative gene VIM-2 on drug resistance. Methods Antibiotic sensibility tests were analyzed by MIC, producing metallo-p-lactamase IPMRPa strains were screened by mixed K-B method. VIM-2 gene was detected by PCR. Results 910 IPMRPa (63.8%) were all multi-drug resistance, whereas among 516 non-IPMRPa(36.2%) strains, multi-drug resistant stains was only 71 stains. Hence it had significant difference (P<0.05). Comparative analyses between IPMRPa and non-IPMRPa strains, apart from tetracycline, the drug resistance of other antibiotics detected had significant difference (P<0.05). The positive ratio of metallo-P-lactamase produced strains was 18.6%( 168/910). blaVIM-2 gene was detected by PCR, and the positive ratio was 80.4%(135/168). Conclusion IPMRPa has strong multi-drug resistance. VIM-2 metallo-P-lactamase has higher positive ratio, but this gene is not the main reason about Pseudomonas aeruginosa produced metallo-P-lactamase strains to the drug resistance with all 12 antibiotics detected exclusive of IPM.%目的 了解临床分离耐亚胺培南铜绿假单胞菌(Imipenem-resistant Pseudomonas aeruginosa,IPMRPa)及其耐药特征,探讨该菌产金属酶和相关基因blaVTM-2对抗菌药物耐药性的影响.方法 收集3年临床分离铜绿假单胞菌,采用MIC法测定抗生素耐药性;用复合纸片法筛查IPMRPa产金属β-内酰胺酶的菌株；聚合酶链反应(PCR)法对金属酶相关基因(blaVIM-2)检测并测序确定.结果 1426株铜绿假单胞菌中IPMRPa为910株(63.8％),均为多重耐药；非IPMRPa的516株(36.2％)中仅有71株多重耐药,两者的多重耐药率比较有显著性差异(P＜0.05).在IPMRPa与非IPMRPa的耐药性比较中发现:除四环素外的其他测试抗生素耐药率均有显著差异(P＜0.05).910株IPMRPa中经复合纸片法检出产金属β-内酰胺酶168株,占18.6％(168/910); 168株采用PCR扩增出135株(80.4％,135/168)携带有blaVIM-2型基因,扩增产物经序列分析均为VIM-2型.结论 IPMRPa多重耐药现象严重,VIM-2型金属酶基因型在产金属β-内酰胺酶的IPMRPa菌株中检出率高,但该基因并不是产金属酶的铜绿假单胞菌对本研究中12种测试抗菌药物耐药的主要原因.