title: Escherichia coli ST131, an intriguing clonal group.
abstract: In 2008, a previously unknown Escherichia coli clonal group, sequence type 131 (ST131), was identified on three continents. Today, ST131 is the predominant E. coli lineage among extraintestinal pathogenic E. coli (ExPEC) isolates worldwide. Retrospective studies have suggested that it may originally have risen to prominence as early as 2003. Unlike other classical group B2 ExPEC isolates, ST131 isolates are commonly reported to produce extended-spectrum β-lactamases, such as CTX-M-15, and almost all are resistant to fluoroquinolones. Moreover, ST131 E. coli isolates are considered to be truly pathogenic, due to the spectrum of infections they cause in both community and hospital settings and the large number of virulence-associated genes they contain. ST131 isolates therefore seem to contradict the widely held view that high levels of antimicrobial resistance are necessarily associated with a fitness cost leading to a decrease in pathogenesis. Six years after the first description of E. coli ST131, this review outlines the principal traits of ST131 clonal group isolates, based on the growing body of published data, and highlights what is currently known and what we need to find out to provide public health authorities with better information to help combat ST131.
authors: Service de Microbiologie, Hôpital Beaujon AP-HP, Clichy, France Faculté de Médecine D. Diderot, Paris, France Institut National de la Santé et de la Recherche Médicale, U773, Centre de Recherche Biomédicale Bichat-Beaujon (CRB3), Université Paris 7, Paris, France mhn.chanoine@bjn.aphp.fr.
authors: Marie-Hélène
authors: MH
authors: Nicolas-Chanoine
authors: Service d'Hygiène Hospitalière, CHRU, Besançon, France UMR 6249 Chrono-Environnement, Université de Franche-Comté, Besançon, France.
authors: Xavier
authors: X
authors: Bertrand
authors: Unité Antibiorésistance et Virulence Bactériennes, ANSES, Lyon, France.
authors: Jean-Yves
authors: JY
authors: Madec
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000145:classification / Q000302:isolation & purification / Q000472:pathogenicity / Q000502:physiology*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control / Q000628:therapy; D023281:Genomics; D006801:Humans; D012307:Risk Factors; D014774:Virulence