Genotyping on 47 Staphylococcus aureus strains associated with bloodstream infection / 中华流行病学杂志

ABSTRACT

Objective To investigate the molecular epidemiological characteristics of Staphylococcus aureus associated with bloodstream infection in hospital. Methods 47 Staphylococcus aureus strains isolated from bloodstream in PLA General Hospital were collected from January 2006 to December 2008. Susceptibility of the strains to 11 antimicrobial agents was detected and DNA homology of them was analyzed with Rep-based DiversiLab~(TM) Microbial Typing System. Panton-Valentine leukocidin (PVL)gene was determined by PCR. For methicillin-resistant Staphylococcus aureus (MRSA) strains,the genotypes of SCCmec were determined and ST239 clone was screened with multiplex PCR. Multilocus sequence typing (MLST) was used to determine the STs of the selected isolates. Results In the 47 Staphylococcus aureus isolated from blood,methicillin-resistant strains accounted for 51.1%,all belonged to SCCmec Ⅲ type,with only 2 pvl gene positive strains identified. 12 different patterns (A-L) were found among 47 strains with Rep-PCR. All MRSA strains clustered in the A and B subtypes. Conclusion Most MRSA strains isolated from blood in PLA General Hospital belonged to ST239-MRSA-SCCmec Ⅲ clone. DiversiLab~(TM) Microbial Typing System could provide a rapid and effective method to investigate the molecular epidemiological characteristics of Staphylococcus aureus in the hospital settings.