食品与临床分离的致病性副溶血性弧菌耐药性比较

Comparison of antimicrobial resistance of pathogenic Vibrio parahaemolyticus in seafood and clinical samples

目的比较食品与临床分离的致病性副溶血性弧菌耐药性差异,为该菌耐药机制研究提供基础。方法运用K-B纸片法,对上海市28株临床菌株、18株食品源菌株的副溶血性弧菌进行耐药性监测,以PCR分析菌株的耐药基因。再用多位点测序技术揭示46株副溶血性弧菌的遗传多样性,针对相同进化分支中不同来源的分离株进行耐药性比较。结果28株临床菌株的耐药率(100%)明显高于18株食品源分离株(88.9%),而且临床菌株全部为多重耐药性菌株(n=28),而食品源中仅有2株具有多重耐药性。临床菌株所携带的耐药基因数量比食品源分离菌株更多、种类更为丰富。多位点测序分型结果也显示相同的趋势,在同一进化分支中,临床菌株的耐药性也显著高于食品分离株。结论本研究系统地比较食品与临床分离的致病性副溶血性弧菌耐药表型与耐药基因型的差异,分析了耐药性形成的原因,为副溶血性弧菌耐药性的起源、传播与控制提供依据。

The aim of this study was to compare the antimicrobial resistance among the pathogenic V.parahaemolyticus isolates from seafood and clinical samples,which provides the data basis for the antibiotic resistance mechanism of V.parahaemolyticus.A total of 46 pathogenic V.parahaemolyticus were isolated from clinical samples（n=28）and seafood samples（n=18）.Antimicrobial resistance phenotypes（18antimicrobials;disk diffusion method）and genotypes（38antimicrobial resistance genes;PCR）of 46 pathogenic V.parahaemolyticus were evaluated.Furthermore,the genetic diversity of 46 isolates was analyzed by multilocus sequence typing（MLST）,and the antimicrobial resistance of isolates in the same clonal complexes was compared.Results showed that the antimicrobial resistance rate of 28 clinical isolates（100%）was obviously higher than that of18seafood-derived isolates（88.9%）.And all clinical isolates were multi-drug resistance bacteria（n=28）,while only 2seafood-derived isolates could tolerate more than 3 kinds of antimicrobials. Additionally, the number and kind of antimicrobial resistance genes of the clinical isolates were more complex than seafood-derived isolates.The similar phenomenon was also observed in these isolates which belonged to the same clonal complexes.This study has revealed the difference of antimicrobial resistance between seafood-derived and clinical V.parahaemolyticus isolates,and analyzed the reason for emergence of antimicrobial resistance in V.parahaemolyticus,which could provide the scientific support for study of the origin,spread and control of the antimicrobialresistant V.parahaemolyticus.