Homologous SCCmec elements in clinical isolates of methicillin-resistant Staphylococcus epidermidis carrying psm-mec / 西安交通大学学报(医学版)

ABSTRACT

Objective To investigate SCCmec types in clinical isolates of methicillin-resistant Staphylococcus epidermidis (MRSE) carrying psm-mec.Methods We collected 165 strains of Staphylococcus epidermidis identified by automated microbiological identification system and screened MRSE by PCR amplification of esp and mecA gene.Strains with psm-mec were identified by amplification of psm-mec,fudoh and p221 DNA fragment;mec,ccr and SCCmec typing was conducted by multiplex PCR assay.Results Among 138 strains of MRSE,29 strains were identified as MRSE with psm-mec,and the carrying rate was 17.58%.Results of mec and ccr typing by multiple PCR showed that MRSE with psm-mec carried Class A mec,but the ccr type had obvious diversity.Results of SCCmec typing showed that all strains with psm-mec belonged to type Ⅱ and/or Ⅲ SCCmec.Conclusion Clinical isolates of MRSE with psm-mec carry homologous type Ⅱ and/or Ⅲ SCCmec harboring Class A mec.