Sola Claudia, Cortes Paulo, Saka Hector A, Vindel Ana, Bocco José Luis
Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina.
J Clin Microbiol. 2006 Jan;44(1):192-200. doi: 10.1128/JCM.44.1.192-200.2006.
Since 1999, a new, epidemic, methicillin-resistant Staphylococcus aureus (MRSA) strain, named the "Cordobes clone," has emerged in Argentina and coexists with the pandemic Brazilian clone. The purpose of this study was to determine the stability over time of the new clone and to investigate its evolutionary relationship with epidemic international MRSA lineages and with other MRSA and methicillin-susceptible S. aureus (MSSA) major clones distributed in this region. One hundred three MRSA isolates recovered in 2001 from Cordoba, Argentina, hospitals and 31 MSSA strains collected from 1999 to 2002 were analyzed by their antibiotic resistance patterns, phage typing, and pulsed-field gel electrophoresis. Additionally, representative members of most MRSA defined genotypes (A, B, C, E, K, and I) were characterized by multilocus sequence typing (MLST) and spaA and SCCmec typing. The most prevalent MSSA pulsotypes were also analyzed by MLST. Our results support the displacement of the Brazilian clone (sequence type [ST] 239, spaA type WGKAOMQ, SCCmec type IIIA) by the Cordobes clone (ST5, spaA type TIMEMDMGMGMK, SCCmec type I) in the hospital environment. MRSA and MSSA isolates shared only ST5. The data support the origin of the Cordobes clone as a member of a lineage that includes the pediatric and New York/Japan international clones and that is genetically related to the British EMRSA-3 strain. Interestingly, the pediatric clone, isolated from most community-acquired infections in Cordoba, was characterized by ST100, a single-locus variant of ST5 and a new variant of SCCmec type related to SCCmec type IVc.
自1999年以来，一种名为“科尔多瓦克隆株”的新型耐甲氧西林金黄色葡萄球菌（MRSA）菌株在阿根廷出现，并与大流行的巴西克隆株共存。本研究的目的是确定新克隆株随时间的稳定性，并研究其与国际流行MRSA谱系以及与该地区分布的其他MRSA和甲氧西林敏感金黄色葡萄球菌（MSSA）主要克隆株的进化关系。通过抗生素耐药模式、噬菌体分型和脉冲场凝胶电泳对2001年从阿根廷科尔多瓦医院分离的103株MRSA菌株以及1999年至2002年收集的31株MSSA菌株进行分析。此外，通过多位点序列分型（MLST）以及spaA和SCCmec分型对大多数已定义的MRSA基因型（A、B、C、E、K和I）的代表性菌株进行特征分析。还通过MLST分析了最常见的MSSA脉冲型。我们的结果支持在医院环境中科尔多瓦克隆株（序列类型[ST]5，spaA类型TIMEMDMGMGMK，SCCmec类型I）取代了巴西克隆株（ST239，spaA类型WGKAOMQ，SCCmec类型IIIA）。MRSA和MSSA分离株仅共享ST5。数据支持科尔多瓦克隆株作为一个谱系成员的起源，该谱系包括儿科和纽约/日本国际克隆株，并且在基因上与英国EMRSA - 3菌株相关。有趣的是，从科尔多瓦大多数社区获得性感染中分离出的儿科克隆株，其特征为ST100，它是ST5的单一位点变体以及与SCCmec IVc型相关的SCCmec新型变体。
