Genotypes and antimicrobial susceptibility of Rhizobium radiobacter isola-ted from pediatric patients with bacteremia / 中国感染控制杂志

ABSTRACT

Objective To investigate genotypes and antimicrobial susceptibility of Rhizobium radiobacter (R.radiobact-er)isolated from pediatric patients with bacteremia.Methods R.radiobacter strains from blood cultures of pediatric pa-tients with bacteremia from February 2013 through February 2014 were collected.16S rDNA fragment was amplified by polymerase chain reaction(PCR),bacterial genotypes were identified by pulsed-field gel electrophoresis (PFGE),antimi-crobial susceptibility testing were performed by Kirby-Bauer disk diffusion method.Results 13 isolates of R.radiobacter were isolated from 12 children with positive blood culture,which including 3 genotypes,the homology of 16S rDNA fragment and R.radiobacter IFM 10623 was up to 99%.According to CLSI 2003 standard,these 13 R.radiobacter were resistant to ceftazidime,piperacillin,ticarcillin,piperacillin/tazobactam,ticarcillin/clavulanic acid,aztreo-nam and polymyxin B,but sensitive to cefepime,doripenem,imipenem,meropenem,tobramycin,netilmicin,cip-rofloxacin,levofloxacin,and norfloxacin.In addition,cefotaxime and ceftriaxone showed larger inhibition zone. Conclusion Therapy of R.radiobacter infection should be based on antimicrobial susceptibility testing results;cefo-taxime and ceftriaxone are better selection for the therapy of R.radiobacter infection in pediatric patients.