ICU分离铜绿假单胞菌耐药特征及菌株聚类分析研究

Drug Resistant Genes in ICU Isolates of Pseudomonas aeruginosa and Cluster Analysis of Strains

目的了解自重症监护病房(ICU)患者分离到的铜绿假单胞菌(PAE)中β-内酰胺类药物耐药相关基因、氨基糖苷类修饰酶基因存在状况和菌株的亲缘性。方法对21株PAE,采用PCR检测β-内酰胺类药物耐药相关基因(TEM、SHV、OXA-10群、PER、VEB、GES、CARB、IMP、VIM、SPM、GIM、DHA、FOX、MOX和oprD2),氨基糖苷类修饰酶基因(aac(3)-Ⅱ、aac(6′)-Ⅰ、aac(6′)-Ⅱ、ant(3″)-Ⅰ、ant(2″)-Ⅰ和aac(3)-Ⅰ)。结果21株PAEβ-内酰胺类药物耐药相关基因中TEM阳性21株(100.0%)、SHV阳性2株(9.5%)、GES阳性1株(4.8%)、CARB阳性2株(9.5%)、VIM阳性4株(19.0%),oprD2基因缺失14株(66.7%),其余基因均阴性;氨基糖苷类修饰酶基因中aac(3)-Ⅱ阳性4株(19.0%)、aac(6′)-Ⅰ阳性5株(23.8%)、aac(6′)-Ⅱ阳性2株(9.5%)、ant(3″)-Ⅰ阳性1株(4.8%)和ant(2″)-Ⅰ阳性4株(19.0%),aac(3)-Ⅰ为阴性。结论ICU患者分离到的铜绿假单胞菌携带多种β-内酰胺酶和氨基糖苷类修饰酶基因,聚类分析显示存在克隆传播医院感染。

OBJECTIVE To investigate the existence of genes for beta-lactam antibiotic resistance and for aminoglycosides modification enzymes （AMEs） in Pseudomonas aeruginosa （PAE） isolates from ICU patients and analyze the homology among strains. METIIODS β-Lactamase genes including TEM, SHV, OXA-10, PER, VEB, GES,CARB,IMP,VIM,SPM,GIM,DHA,FOX, MOX and oprDz ,were detected by PCR amplication in 21 PAE isolates. The genes for AMES including aac（3）- Ⅰ , aac（3）- Ⅱ , aac（6＇）- Ⅰ , aac（6＇）- Ⅱ , ant（3＂）- Ⅰand ant（2＂）- Ⅰ were determined by PCR amplification as well. RESULTS Among 21 isolates 21（100%）, 2（9.5%）, 1 （4.8%）, 2 （9.5% ） and 4 （19.0% ） were positive for TEM, SHV, GES, CARB and VIM genes, respectively. The deletion of oprD2 gene was found in 14 out of 21 strains. Other 13-1actamase genes were absent in all isolates. As for AME genes,aac（3）-Ⅱ , aac（6＂）-I ,aac（6）-Ⅱ ,ant（3＂）-Ⅰ ,ant（2＂）-Ⅰ and aac（3）-I genes were present in 19.0%, 23.8%, 9.5%, 4. 8%, and 19.0% of 21 isolates, However, aac（3）- I gene was no position in any isolates. CONCLUSIONS P. aeruginosa carries various beta-lactamase and AME genes in ICU patients. Genetic cluster analysis suggested that clonal propagation result in nosocomial infection of PAE.