汕头地区医院感染多重耐药铜绿假单胞菌的基因型特征分析

目的了解汕头地区ICU和非ICU医院感染多重耐药铜绿假单胞菌分离株的基因型特征。方法收集汕头地区两家三级甲等医院的医院感染铜绿假单胞菌菌株,对这些菌株的耐药性和基因型进行分析。采用纸片扩散法进行药敏试验,脉冲场凝胶电泳法对多重耐药菌株进行基因分型,电泳结果用BionumericsV4.0软件进行聚类分析。结果共分离到132株铜绿假单胞菌,其中45株分离自ICU,87株来自非ICU病房。132株菌株中,有46株多重耐药菌（耐三种抗菌素或以上）。对46株多重耐药菌（25株来自ICU,21株来自非ICU病房）进行脉冲场凝胶电泳,结果显示来自ICU病房的25株菌株具有较高程度的同源性,而来自非ICU病房的菌株则具有明显的基因多态性。结论交叉感染是ICU多重耐药铜绿假单胞菌医院感染的重要传播途径。

Genotypic characterization of multiple antibiotic-resistant Pseudomonas aeruginosa isolated from patients with nosocomial infections in Shantou

Objective This study was to explore the molecular characteristics of multiple antibiotic-resistant Pseudomonas aeruginosa isolated from patients with nosocomial infection.Methods Various strains of Pseudomonas aeruginosa were collected from two tertiary hospitals in Shantou city between January and June 2008.Antibiotic susceptibility test was conducted using the disc diffusion method.Pulsed-field gel electrophoresis （PFGE） method was used for molecular typing of Pseudomonas aeruginosa isolates.The patterns of PFGE were analyzed by using Bionumerics 4.0 software.Results A total of 132 Pseudomonas aeruginosa strains were obtained,including 45 strains from ICU and 87 strains from common wards.Of 132 strains,46 strains were multiple antibiotic-resistant（resistant to 3 antibiotics or more）.PFGE analysis showed that the isolates obtained from ICU ward had a high degree of genetic homology.In contrast,a high degree of genetic heterogeneity was found in the isolates obtained from the non-ICU wards.Conclusion Cross-infection may be a route of infection in the spreading of nosocomial infections caused by multiple antibiotic-resistant Pseudomonas aeruginosa in ICU.