Staphylococcal cassette chromosome mec typing of and detection of PVL gene in 84 methicillin-resistant Staphylococcus aureus isolates from patients with infectious skin diseases

Abstract

Objective To determine staphylococcal cassette chromosome mec (SCCmec) types and detect panton-valentine leukocidin (PVL) gene in methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients with infectious skin diseases.Methods Staphylococcus aureus was isolated from lesion exudate of patients with infectious skin diseases between June 2010 and July 2012 in different departments of Affiliated Hospital of Inner Mongolia Medical University.General and medical information on the patients was collected as well.PCR was performed to detect mecA gene in MRSA strains,and multiplex PCR was conducted to determine SCCmec type and detect PVL gene in mecA gene-positive strains.Results A total of 95 MRSA strains were isolated from these patients with infectious skin diseases,and mecA gene was found in 84 out of these strains.Among these mecA-positive strains,5 carried PVL gene,69 (86.3％) were identified as SCCmec type Ⅲ,3 (3.6％) as SCCmec type Ⅰ,8 (9.52％) as SCCmec type Ⅳ,4 (4.8％) were non-typeable,and no strain was identified as SCCmec type Ⅱ or W.Conclusions Hospital-acquired (HA)-MRSA predominates in MRSA strains causing infectious skin diseases,with SCCmec type Ⅲ as the major SCCmec type.Both HA and community-acquired (CA) MRSA strains carry PVL toxin. Key words: Infection; Skin; Genes, SCCmec; PVL toxin