Laboratorio de Referencia de E. coli (LREC), Departamento de Microbioloxía e Parasitoloxía, Facultade de Veterinaria, Universidade de Santiago de Compostela, Lugo, Spain.
Int J Antimicrob Agents. 2011 Jan;37(1):16-21. doi: 10.1016/j.ijantimicag.2010.09.012. Epub 2010 Nov 13.
CTX-M enzymes, mainly CTX-M-14 and CTX-M-15, have emerged as the most prevalent extended-spectrum β-lactamase (ESBL) type produced by Escherichia coli in Spain, with successful dissemination of clonal group O25b:H4-B2-ST131 producing CTX-M-15 within the hospital and community settings. However, until now CTX-M-14-producing E. coli in Spain had been shown to belong to a wide variety of serotypes with no predominance of a certain clonal group. In the present study, 654 E. coli strains positive for ESBL production obtained between 2005 and 2008 from inpatients and outpatients of four hospitals in Galicia, northwest Spain, were analysed. The strains were characterised with regard to ESBL enzymes, serotype, virulence genes, phylogenetic group, multilocus sequence type, and pulsed-field gel electrophoresis of XbaI-digested DNA. As a result, the emergence of certain clonal groups of extraintestinal pathogenic E. coli producing CTX-M-14 has been detected in this geographic area, including O1:HNM-D-ST59, O15:H1-D-ST393/ST1394, O20:H34/HNM-D-ST354, O25b:H4-B2-ST131 and ONT:H21,42-B1-ST101. These five clonal groups showed a high virulence potential as they harboured more than eight virulence factors, which could explain their successful dissemination.
CTX-M 酶，主要是 CTX-M-14 和 CTX-M-15，已成为西班牙产大肠埃希菌中最普遍的扩展谱β-内酰胺酶 (ESBL) 类型，具有成功传播的克隆群 O25b:H4-B2-ST131 产生 CTX-M-15，在医院和社区环境中。然而，到目前为止，在西班牙，产 CTX-M-14 的大肠埃希菌已被证明属于多种血清型，没有特定克隆群的优势。在本研究中，分析了 2005 年至 2008 年间从西班牙西北部加利西亚的四家医院的住院患者和门诊患者中获得的 654 株产 ESBL 的大肠埃希菌。这些菌株的 ESBL 酶、血清型、毒力基因、进化群、多位点序列型和 XbaI 消化 DNA 的脉冲场凝胶电泳进行了特征分析。结果表明，在该地理区域已检测到某些产 CTX-M-14 的肠外致病性大肠埃希菌的克隆群的出现，包括 O1:HNM-D-ST59、O15:H1-D-ST393/ST1394、O20:H34/HNM-D-ST354、O25b:H4-B2-ST131 和 ONT:H21,42-B1-ST101。这五个克隆群表现出较高的毒力潜力，因为它们携带了超过 8 种毒力因子，这可以解释它们的成功传播。
