Laboratório Especial de Microbiologia Clínica, Departamento de Doenças Infecciosas e Parasitárias, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
Braz J Med Biol Res. 2011 Oct;44(10):1013-7. doi: 10.1590/s0100-879x2011007500114. Epub 2011 Sep 2.
An increased incidence of nosocomial and community-acquired infections caused by methicillin-resistant Staphylococcus aureus (MRSA) has been observed worldwide. The molecular characterization of MRSA has played an important role in demonstrating the existence of internationally disseminated clones. The use of molecular biology methods in the surveillance programs has enabled the tracking of MRSA spread within and among hospitals. These data are useful to alert nosocomial infection control programs about the potential introduction of these epidemic clones in their areas. Four MRSA blood culture isolates from patients hospitalized at two hospitals in the city of São Paulo, Brazil, were analyzed; one of them was community acquired. The isolates were characterized as SCCmec, mecA and PVL by PCR, pulsed-field gel electrophoresis (PFGE) profile and molecular sequence typing (MLST) genotyping. The isolates presented type IV SCCmec, and none proved to be positive for PVL. The isolates showed a PFGE profile similar to the pediatric clone. MLST genotyping demonstrated that the isolates belonged to clonal complex 5 (CC5), showing a new yqiL allele gene, resulting in a new sequence typing (ST) (1176). Our results showed that strains of MRSA carrying a new ST are emerging in community and nosocomial infections, including bacteremia, in São Paulo, Brazil.
耐甲氧西林金黄色葡萄球菌（MRSA）引起的医院内和社区获得性感染的发生率在全球范围内有所增加。MRSA 的分子特征在证明国际传播克隆的存在方面发挥了重要作用。分子生物学方法在监测计划中的应用使我们能够追踪医院内和医院间的 MRSA 传播。这些数据有助于提醒医院感染控制计划注意这些流行克隆在其地区的潜在引入。对来自巴西圣保罗市两家医院住院患者的 4 株耐甲氧西林金黄色葡萄球菌血培养分离株进行了分析；其中一株为社区获得性感染。通过 PCR、脉冲场凝胶电泳（PFGE）图谱和分子序列分型（MLST）基因分型对分离株进行了 SCCmec、mecA 和 PVL 分析。分离株呈现 IV 型 SCCmec，且均未检测到 PVL 阳性。分离株的 PFGE 图谱与儿科克隆相似。MLST 基因分型表明，这些分离株属于克隆复合体 5（CC5），携带新的 yqiL 等位基因，导致新的序列分型（ST）（1176）。我们的研究结果表明，携带新 ST 的 MRSA 菌株正在巴西圣保罗的社区和医院感染中出现，包括菌血症。
