Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogotá, Colombia.
J Clin Microbiol. 2010 May;48(5):1562-9. doi: 10.1128/JCM.02526-09. Epub 2010 Mar 10.
Enterococcus faecium has emerged as an important nosocomial pathogen worldwide, and this trend has been associated with the dissemination of a genetic lineage designated clonal cluster 17 (CC17). Enterococcal isolates were collected prospectively (2006 to 2008) from 32 hospitals in Colombia, Ecuador, Perú, and Venezuela and subjected to antimicrobial susceptibility testing. Genotyping was performed with all vancomycin-resistant E. faecium (VREfm) isolates by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. All VREfm isolates were evaluated for the presence of 16 putative virulence genes (14 fms genes, the esp gene of E. faecium [espEfm], and the hyl gene of E. faecium [hylEfm]) and plasmids carrying the fms20-fms21 (pilA), hylEfm, and vanA genes. Of 723 enterococcal isolates recovered, E. faecalis was the most common (78%). Vancomycin resistance was detected in 6% of the isolates (74% of which were E. faecium). Eleven distinct PFGE types were found among the VREfm isolates, with most belonging to sequence types 412 and 18. The ebpAEfm-ebpBEfm-ebpCEfm (pilB) and fms11-fms19-fms16 clusters were detected in all VREfm isolates from the region, whereas espEfm and hylEfm were detected in 69% and 23% of the isolates, respectively. The fms20-fms21 (pilA) cluster, which encodes a putative pilus-like protein, was found on plasmids from almost all VREfm isolates and was sometimes found to coexist with hylEfm and the vanA gene cluster. The population genetics of VREfm in South America appear to resemble those of such strains in the United States in the early years of the CC17 epidemic. The overwhelming presence of plasmids encoding putative virulence factors and vanA genes suggests that E. faecium from the CC17 genogroup may disseminate in the region in the coming years.
屎肠球菌已成为全球重要的医院获得性病原体，这种趋势与克隆群 17（CC17）指定的遗传谱系的传播有关。从哥伦比亚、厄瓜多尔、秘鲁和委内瑞拉的 32 家医院前瞻性收集肠球菌分离株（2006 年至 2008 年），并进行药敏试验。所有万古霉素耐药屎肠球菌（VREfm）分离株均通过脉冲场凝胶电泳（PFGE）和多位点序列分型进行基因分型。评估所有 VREfm 分离株是否存在 16 个假定的毒力基因（14 个 fms 基因、屎肠球菌 esp 基因（espEfm）和 hyl 基因[hylEfm]）和携带 fms20-fms21（pilA）、hylEfm 和 vanA 基因的质粒。在回收的 723 株肠球菌分离株中，屎肠球菌最常见（78%）。检测到 6%的分离株对万古霉素耐药（其中 74%为屎肠球菌）。在 VREfm 分离株中发现了 11 种不同的 PFGE 型，其中大多数属于序列类型 412 和 18。在该地区的所有 VREfm 分离株中均检测到 ebpAEfm-ebpBEfm-ebpCEfm（pilB）和 fms11-fms19-fms16 簇，而 espEfm 和 hylEfm 分别在 69%和 23%的分离株中检测到。fms20-fms21（pilA）簇编码一种假定的菌毛样蛋白，存在于几乎所有 VREfm 分离株的质粒上，有时与 hylEfm 和 vanA 基因簇共存。南美洲 VREfm 的群体遗传学似乎与 CC17 流行早期美国的此类菌株相似。编码假定毒力因子和 vanA 基因的质粒的大量存在表明，来自 CC17 基因群的屎肠球菌可能在未来几年内在该地区传播。
