Characteristics of drug resistance and molecular typing for Salmonella in diarrhea patients from four hospitals in Shenzhen / 中国人兽共患病学报

ABSTRACT

We analyzed the antimicrobial resistance and pulsed field gel electrophoresis (PFGE) patterns of Salmonella strains of infectious diarrhea isolated four hospitals in Shenzhen during 2012-2016.A total of 137 Salmonella strains collected in 4 hospitals in Shenzhen were identified by serotyping,micro-dilution method was used to detect the antimicrobial susceptibility of the isolates.Pulsed field gel-electrophoresis(PFGE) was used for molecular typing and cluster analysis of S.typhimurium and S.enterica strains.Results showed that 137 strains of Salmonella were divided into 30 kinds of serotype.S.typhimurium was the predominant serotype.The drug susceptibility test indicated that the antibiotic resistance of the strains to chloromycetin,ampicillin and amoxicillin were more serious than other drugs,the resistance to penicillins,cephalosporins,aminolycosides and macrolides showed increase trends year by year.Of 49 strains of S.typhimurium were divided 38 molecular patterns by PFGE,with similarity ranged from 65.5％ 100％,TY18 was the main PFGE pattern.The 27 strains of S.enterica were divided into 7 molecular patterns by PFGE,with similarity ranged from 61.8％-100％,EN7 was the main PFGE pattern.The status of drug resistance of infectious diarrhea isolates was rather severe,PFGE patterns showed diversity,suggesting the diarrhea cases were distributed sporadically.Partial PFGE patterns and its corresponding antidrug spectrum have certain aggregation relationship.