耐甲氧西林金黄色葡萄球菌分子流行病学研究

Molecular epidemiology of methicillin-resistant staphylococcus aureus

目的研究某院临床分离耐甲氧西林金黄色葡萄球菌(MRSA)分子流行病学特点,为临床预防、MRSA流行监测,制定防治方案等提供科学依据。方法采用药敏纸片法和PCR技术对从住院患者、医务人员及环境分离的MRSA进行表型、基因型鉴定,检测其杀白细胞毒素(pvl)基因,并进一步对mecA基因阳性标本进行SCCmec基因分型。结果从1352份标本中分离出108株金黄色葡萄球菌,MRSA为54株,主要分离于烧伤科占77.78%;根据SCCmec基因分型结果,54株MRSA以Ⅲ型为主,占68.52%,pvl基因均为阴性。结论某院MRSA临床检出率与2008年监测的数据相仿,流行情况以Ⅲ型SCCmec基因型为主,提示医院MRSA临床株与环境株之间MRSA可能具有同源性,临床必须采取严格措施加以控制。

OBJECTIVE To study the characteristic of molecular epidemiology of MRSA isolated from one hospital in Ningxia province, and provide scientific evidence for preventing and monitoring the spread of MRSA. METHODS Disk diffusion method and PCR were used to identify phenotype and genotype of the MRSA strain isolated from hospitalized patients, hospital environment and medical staff, then to detect the panton-valentine leukoeidin gene （pvl）. The genotypes of Staphylococcal chromosomal cassettemec （SCCmec） were detemined by multiplex PCR. RESULTS The 108 strains of S. aureus could include 54 isolates of MRSA mainly from the burn unit （77.78%）. SCCmec typing showed that most isolates were Ⅲ type （68.52%）, pvl gene were all negative. CONCLUSION The clinical detection rate of MRSA in a hospital is similar to the national average monitoring data in 2008. The most type of SCCmec is Ⅲ, prompting that the hospital MRSA strains and environmental MRSA strains could be homologous. Clinical departments and hospital infection must take strict measures to control it.