副猪嗜血杆菌4型分离株耐药表型及耐药基因分析研究

Analysis of Drug Resistance Phenotype and Gene of Haemophilus Parasuis Type 4

为了解掌握副猪嗜血杆菌4型(Haemophilus parasuis serotype4,HPS4)临床分离菌株的耐药性和耐药基因携带情况。试验选用6大类18种常用抗菌药物,通过药敏纸片扩散法对10株HPS4菌株的耐药性进行检测研究,并通过PCR方法检测了菌株携带氨基糖苷类和喹诺酮类药物的耐药基因情况。结果表明,被检菌株对红霉素、阿奇霉素、替米考星、四环素、土霉素、强力霉素和氟苯尼考有很好敏感性,耐药率均为10%;对头孢噻呋、头孢他啶和大观霉素较敏感,耐药率为20%;对氨基糖苷类卡那霉素、阿米卡星、新霉素和喹诺酮类诺氟沙星、左氟沙星、氧氟沙星表现出较高耐药性,耐药率均在50%以上,且所有菌株均表现出3重及以上多重耐药现象。10株HPS4菌株共检出了strB、aphA1、gyrA、parC 4种耐药基因,检出率分别为50%、60%、80%、80%,结合耐药表型结果,表明这4种耐药基因可能是介导HPS4菌株对氨基糖苷类及喹诺酮类药物产生耐药性的主要原因。研究为临床防控副猪嗜血杆菌4型选药用药提供了科学的理论依据,充实了副猪嗜血杆菌耐药谱的数据库,为进一步研究其耐药机制奠定基础。

To understand the drug resistance and gene carrying of Haemophilus parasuis serotype 4(HPS4)clinical isolates.The drug resistance of 10 strains of HPS4 was detected by the method of drug sensitive disk diffusion,and the drug resistance genes of aminoglycosides and quinolones were detected by PCR.The results showed that the tested strains were sensitive to erythromycin,azithromycin,tilmicosin,tetracycline,oxytetracycline,doxycycline and florfenicol,with the drug resistance rate of 10%;to ceftiofur,ceftazidime and spectinomycin,with the drug resistance rate of 20%;to aminoglycoside kanamycin,amikacin,neomycin and quinolones norfloxacin,levofloxacin,ofloxacin the drug resistance rate of floxacin was more than 50%,and all strains showed three or more multiple drug resistance.strB,aphA1,gyrA and parC 4 genes were detected in 10 strains of HPS4,the detection rates were 50%,60%,80%and 80%respectively.Combined with the results of drug resistance phenotype,it was suggested that these four genes might be the main reason for the drug resistance of HPS4 to aminoglycosides and quinolones.This study provides a scientific theoretical basis for the clinical prevention and control of the drug selection of Haemophilus parasuis type 4,enriches the database of the drug resistance spectrum of Haemophilus parasuis,and lays a foundation for further study of its drug resistance mechanism.