Leukocidin prevalence and molecular epidemiology of methicillin-resistant Staphy-lococcus aureus
- VernacularTitle:MRSA杀白细胞素基因检测和SCCmec分子流行病学调查
- Author:
Hong ZHANG
;
Wanhua LI
;
Qin CAI
;
Lizhong HAN
;
Yibo ZHANG
- Publication Type:Journal Article
- Keywords:
methicillin-resistant Staphylococcus aureus;
staphylococcal cassette chromosomal mec;
Panton-Valentine leukocidin;
multiplex polymerase chain reaction
- From:
Chinese Journal of Infection and Chemotherapy
2009;09(4):248-251
- CountryChina
- Language:Chinese
-
Abstract:
Objective Methicillin-resistant Staphylococcus aureus (MRSA) is a growing public health concern that has been associated with pediatric fatalities. This study investigated the genotypes of staphylococcal cassette chromosomal mec (SCCmec) and Panton-Valentine Leukocidin (PVL) in MRSA strains isolated from Shanghai Children's Hospital by PCR. Methods A total of 30 strains of MRSA were isolated from various clinical specimens from October 2005 to June 2006. The antimicrobial susceptibility was measured by agar diffusion method. SCCmec typing was conducted using a novel multiplex PCR assay allowing for concomitant detection of methicillin resistance (mecA gene) to facilitate detection and classification of all currently described SCCmec typesⅠ, Ⅱ, Ⅲ, Ⅳa, b, c, d andⅤ. PVL gene was also determined by PCR. Results mecA gene was positive in all the strains. SCCmecⅡ was identified in 6(20.0%) isolates, SCCmecⅢ in 15(50.0%) isolates, SCCmecⅤ in 2 and SCCmecⅣa in 1 isolate. Six MRSA strains were non-typeable. The isolates with SCCmecⅡ or SCCmecⅢ were resistant to multiple antibiotics. The strains harboring SCCmecⅣa or SCCmecⅤwere susceptible to all antibiotics except β-lactams. Eleven (36.7%) isolates were PVL positive. The genotypes and subgenotypes of staphylococcal chromosomal cassette mec of eleven PVL-positive MRSA were SCCmecⅡ(1 isolates), SCCmecⅢ (5 isolates), SCCmecⅣa (1 isolate), SCCmecⅤ (2 iso-Lates) non-typeable (2 isolates). Conclusions SCCmecⅡ and SCCmecⅢ are the major genotypes of MRSA in our hospital. These isolates are multi-resistant to antibiotics. The prevalence of PVL gene is higher in SCCmecⅡ- or SCCmeⅢ-positive MRSA. The isolates with SCCmecⅡ or SCCmecⅢ were resistant to multiple antibiotics.
