铜绿假单胞ESBLs基因分布及同源性分析

目的研究温州医学院附属第一医院临床分离铜绿假单胞菌超广谱β-内酰胺酶（EsBL8）产生情况、基因分布及流行特性，为临床合理使用抗菌药物、控制耐药性的传播提供理论依据。方法选取2005—2009年每年6-9月临床连续分离非重复铜绿假单胞菌共169株。PCR方法检测超广谱β-内酰胺酶基因（TEM、SHV、VEB、PER、GES、TLA、IBC、CTX—M-1、CTX—M-2、CTX—M-8、CTX—M-9、OXAⅠ、OXAⅡ、OXAⅢ、OXAⅣ和OXAⅤ）。采用脉冲场凝胶电泳技术（PFGE）分析产超广谱β-内酰胺酶的铜绿假单胞菌株间的同源性。结果169株铜绿假单胞菌，经PCR方法检测，检出产超广谱β-内酰胺酶菌株84株，阳性率为49．7％；169株PA中检出TEM、CTX—M-9、CTX—M-1、CTX—M-2、OXAⅠ、OXAⅣ、GES、OXAⅡ基因型各占32．0％，5．3％，4．7％，2．4％，1．8％，1．8％，1．2％，0．6％。在54株TEM阳性PA中，挑取同一病区不同患者不同标本分离的铜绿假单胞菌共21株，利用PFGE分析其同源性，多呈现散发流行，仅三株具有同源性。结论铜绿假单胞菌超广谱β-内酰胺酶基因型以TEM为主，GES、CTX—M-1、CTX—M-2、CTX—M-9、OXAⅠ、OXAⅡ、OXAⅣ等基因都有检出，未检出PER基因。脉冲场凝胶电泳结果显示，本院临床分离的铜绿假单胞菌大多无同源性，呈散发流行趋势，个别病区存在轻微的克隆播散现象。

GeneticCharacteristics and Homologous Analysis of Pseudomonas Aeruginosa ESBLs

Objective To investigate the prevalence of Pseudomonas aeruginosas isolated from the first affiliated hospital of Wenzhou Medical College. This study,we hope,can he used as theoretical basis for the clinicians in correct medication. Methods A total of 169 consecutive clinical strains of Pseudomonas aeruginosa were selected from June to September annually between 2005 to 2009,ES- BLs genes were detected by PCR,the ESBLs genes contain TEM,SHV,VEB,PER,GES,TLA,IBC,CTX-M-1,CTX-M-2,CTX-M-8, CTX-M-9,OXA Ⅰ, OXA Ⅱ, OXA Ⅲ ,OXAⅣ ,and OXA Ⅴ ;The Pulsed-Field Gel Electrophoresis（PFGE）was used to determine the clonal relatedness. Results Of the 169 isolates,84 strains of Pseudomonas aeruginosa were positive to extended-spectrum β-lactamase gene with PCR method,the positive rate was 49.7%;TEM,CTX-M-9,CTX-M-1,CTX-M-2,OXA Ⅰ,OXAⅣ,GES,OXAⅡ genes were detected in169 stain of the PA,respectively were 32.0%,5.3%,4.7%,24%,1.8%,1.8%,1.2%,0.6%. 21 isolates were selected from 54 TEM carriers according to different samples and different patients in the same satate. All isolates were also characterized by pulsed-field Gel electrophoresis（PFGE）to determine the genetic relateness among these isolates,only 3 strains had homology and those had not homology to be prevalent. Conehlsion TEM were mainly ESBLs genes,other genes include GES,CTX-M-1,CTX-M-2,CTX-M-9,OXA Ⅰ ,OXA Ⅱ and OXAⅣ. Among the detemined Pseudomonas aeruginosas,there are many distinct clones;which suggest that there are little clonal relatedness among the isolates in the hospital.