野生动物园不同源性VRE耐药性及REP-PCR分型研究

Molecular typing through REP-PCR and detection of drug resistant of VRE isolated from different sources in safari park

为了解福州市野生动物园内不同源性耐万古霉素肠球菌的耐药现状及亲缘情况,进而指导兽医临床合理用药,并对控制耐药性传播提供理论依据。用微量肉汤法对6种抗生素进行药敏试验,PCR法检测VanA、VanB、VanC1和VanC2/C3基因,并采用重复基因外回文序列PCR分析技术（REP-PCR）,对分离自不同源性的耐万古霉素肠球菌进行基因多样性研究,比较菌株之间的亲缘关系。结果显示,福州市动物园内不同源性肠球菌分离到VRE共41株,耐药率高达100%,其中红霉素（100%）、土霉素（97.58%）和氯霉素（86.67%）耐药率最高;氨苄西林和万古霉素敏感率分别为92.12%和84.85%;万古霉素相关耐药基因VanA检出率为4.88%,VanB基因检出率为17.07%,VanC1基因检出率为31.71%,VanC2/C3基因检出率为39.02%;REP-PCR分型结果显示,不同来源的耐万古霉素肠球菌菌株大致可分为2～3个型,其中,分离自动物园环境的H2和H3、H1、H8和H9及分离自动物园不同动物的M9和NL6、MH5和MH8、M3、BM3和L6具有100%同源性。结果表明,动物园内肠球菌整体耐药情况较严重,耐药基因VanA、VanB、VanC1和VanC2/C3基因与多重耐药具有相关性;动物源性、环境源性和人员性VRE之间发现同源性100%的菌株,可能存在同一菌株的垂直克隆传播,不同源性VRE之间存在一定的流行病学相关性。

To investigate the drug resistance and relative affinity of different source of vancomycin-resistant Enterococci（VRE） from Safari Park,and to provide the basis for the prevention and treatment of VER-related infections.Six kinds of antibiotics were tested by micro-broth,and VanA,VanB1,VanC1 and VanC2/C3 genes were detected by PCR.The recombinant plasmids were analyzed by reverse transcription-polymerase chain reaction（PCR） of vancomycin-resistant enterococci for gene diversity studies,to compare the genetic relationship between strains.The resistant rate of erythromycin（100% ）,oxytetracycline（97.58% ） and chloramphenicol（86.67% ） was the highest in the VRE 41 strains of different pathogenic Enterococci in Fuzhou zoo.The sensitivity rates of ampicillin and vancomycin were 92.12% and 84.85% ,The detection rate of vancomycin-related resistance gene was 4.88% ,the detection rate of VanB gene was 17.07% ,the detection rate of VanC1 gene was 31.71% and the detection rate of VanC2/C3 gene was 39.02% .The results of the REP-PCR typing showed that the vancomycin-resistant enterococcus strains could be divided into 2-3 types in different origins,including H2 and H3,H1,H8 and H9 isolated from the zoo environment and isolated from different animals M9 and NL6,MH5 and MH8,M3,BM3 and L6 have 100% homology.The whole drug resistance of Enterococcus in the zoo was more serious,and the resistance genes VanA,VanB,VanC1 and VanC2/C3 were correlated with multidrug resistance homology was found between VRE of animal origin,environment and human 100% of the strains,there may be the same strain of vertical clonal propagation,there is a certain epidemic between the different VRE epidemiological relevance.