外科重症监护室多重耐药铜绿假单胞菌的对比基因组学研究

目的 对比分析外科重症监护室多重耐药铜绿假单胞菌的基因组差异,探索其与多重耐药性的关系.方法 琼脂稀释法检测49株铜绿假单胞菌对临床常用9种抗菌药物的敏感性,应用4种稀有位点核酸内切酶结合的脉冲场凝胶电泳技术(PFGE)对临床分离的株铜绿假单胞菌进行基因组分型.结果 多重耐药铜绿假单胞菌菌株占外科重症监护室铜绿假单胞菌临床分离株的85.7%;PFGE基因组型A菌株占全部铜绿假单胞菌分离株的61.2%,为主导基因组型,该基因组型全部对阿米卡星和头孢吡肟敏感,对左旋氧氟沙星和美洛培南耐药;PFGE基因组型H、P菌株对6种以上抗生素耐药;PFGE基因组型I和J菌株对所测9种抗生素均敏感.结论 4种稀有位点核酸内切酶结合的PFGE基因组分型可以作为临床多重耐药铜绿假单胞菌监控和鉴定的有效手段.

Genomic comparisons of multiresistant Pseudomonas aeruginosa isolates obtained from surgical intensive care unit

Objective To investigate the genetic differences and their relativity with multi-drug resistance of Pseudomonas aeruginosa isolated.Methods Forty-nine Pseudomonas aeruginosa isolates were characterized by antimicrobial susceptibility and four-enzyme (I-Ceu I,Spe I,Swa I,Pac I) pulsed-field gel electrophoresis (PFGE).Results 85.7% of the P.aeruginosa isolates were MDR strains.Strains with PFGE pattern A were all susceptible to amikacin and cefepime, but were resistant to levofloxacin and meropenem.Strains with PFGE Patterns H and P had resistance to 6-8 different kinds of antibiotics.Strains with PFGE Patterns I and J were susceptible to all antibiotics tested in this study.Strains with other PFGE Patterns had intermediate resistance.PFGE pattern A was the dominant pattern, which accounted for 61.2% of all P.aeruginosa strains, 100 % (2/2) in 2001, 65% (13/20) in 2002, 44.4% (8/18) in 2003 and 77.8% (7/9) in 2004.Conclusion Four-enzyme combined PFGE analysis is highly discriminatory for the subtyping of MDR P.aeruginosa isolates.