Identification and homology analysis of Ochrobactrum-like species infection in bloodstream of children / 临床检验杂志

ABSTRACT

Objective To identify and analyze the homology of Ochrobactrum isolated from clinical blood samples of children.Methods The 26 strains of Ochrobactrum anthropi were identified by Vitek 2 Compact and test strips of API 20 NE bacterial identification system.The biochemical phenotypes were identified by manual tests.The 16S rRNA and recA gene were amplified by PCR and sequenced.The drug sensitivity tests of Ochrobactrum anthropi were performed by Vitek 2 Compact and matched GN13 card.The homology was analyzed by pulsed field gel electrophoresis.Results Based on the identification of the instruments and the manual tests for biochemical phenotype,all the 26 experimental strains were Ochrobactrum anthropi.The results of sequencing for 16S rRNA and recA gene amplification products showed 25 strains were Pseudochrobactrum saccharolyticum and the other 1 was O.grignonensein.Drug sensitivity analysis showed that the all the 26 strains were resistant to aztreonam,but the sensitive rates to quinolones,aminoglycosides,trimethoprim sulfamethoxazole,four generation of cephalosporins and the antibiotics compound of piperacillin/tazobactam were all more than 80％.Pulsed field gel electrophoresis analysis showed that the 25 strains were highly homologous with differences of only 1 to 3 bands in fingerprint profiles.Conclusion Based on the biochemical phenotype and the sequencing of 16S rRNA and recA gene,the Ochrobactrum-like bacteria could be identified to the level of species.The highly homologous strains of Pseudochrobactrum saccharolyticum may be sourced from a clustered infection.