Department of Medical Microbiology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, RJ, 21941-590, Brazil.
Diagn Microbiol Infect Dis. 2009 Nov;65(3):300-5. doi: 10.1016/j.diagmicrobio.2009.07.023. Epub 2009 Sep 11.
Usually, community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is susceptible to a variety of non-beta-lactam drugs. These isolates commonly display SCCmecIV and are associated with community-acquired infections. More recently, CA-MRSA has been isolated from health-care-associated diseases. We characterized MRSA isolates from 2 hospitals in Rio de Janeiro area to assess the entry of new lineages. The isolates were primary genotyped using a combination of molecular typing methods including SCCmec, restriction modification test, and Panton-Valentine leukocidin (PVL) detection. Pulsed-field gel electrophoresis was carried out for representatives of each lineages found. Disk diffusion test was performed as recommended by the Clinical and Laboratory Standards Institute. SCCmecIV was the predominant cassette mec detected. The most frequent MRSA lineage, a PVL nonproducer, was allocated in the CC1-SCCmecIV. It was found that 56% of these isolates were resistant to 3 or more non-beta-lactam drugs. Multilocus sequence typing of a representative of the CC1 isolates supported our finds that multiresistant variants of a CA-MRSA lineage (ST1-SCCmecIV) emerged in this city.
通常情况下，社区获得性耐甲氧西林金黄色葡萄球菌（CA-MRSA）对多种非β-内酰胺类药物敏感。这些分离株通常显示 SCCmecIV 并与社区获得性感染有关。最近，CA-MRSA 已从与医疗保健相关的疾病中分离出来。我们对来自里约热内卢地区的 2 家医院的 MRSA 分离株进行了特征分析，以评估新谱系的进入。使用包括 SCCmec、限制修饰试验和 Panton-Valentine 白细胞毒素 (PVL) 检测在内的分子分型方法组合对分离株进行了初步基因分型。对发现的每个谱系的代表进行脉冲场凝胶电泳。根据临床和实验室标准协会的建议进行了纸片扩散试验。SCCmecIV 是检测到的主要盒 mec。最常见的 MRSA 谱系（不产生 PVL）被分配到 CC1-SCCmecIV 中。结果发现，这些分离株中有 56%对 3 种或以上非β-内酰胺类药物耐药。CC1 分离株的代表的多位点序列分型支持我们的发现，即该城市出现了 CA-MRSA 谱系（ST1-SCCmecIV）的多耐药变体。
