title: Increase of widespread A, B1 and D Escherichia coli clones producing a high diversity of CTX-M-types in a Portuguese hospital.
abstract: OBJECTIVE
  To characterize temporal shifts in extended-spectrum β-lactamases (ESBLs) and clones of clinical Escherichia coli isolates.
  
  
  METHODS
  All ESBL-producing E. coli isolates from a Portuguese hospital (n = 112; June 2006-June 2007 and January-December 2010) were characterized by identification of phylogenetic groups, ESBL-types and virulence genes, XbaI-PFGE and MLST.
  
  
  RESULTS
  We observed a substantial increase in widespread E. coli clones from phylogroups A, B1 and D (e.g., ST10, ST23, ST117, ST155, ST648) producing mainly CTX-M-1, -14, -32 or SHV-12, along with a decrease in the proportion of the predominant CTX-M-15-producing B2-ST131 clone.
  
  
  CONCLUSIONS
  The amplification of diverse CTX-M-producing A, B1 and D clonal complexes, which have been long identified in Portuguese nonclinical settings, unveils a role for these reservoirs in the landscape of ESBL-producing E. coli in the clinical setting.
authors.affiliation: UCIBIO/REQUIMTE, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors.forename: Carla
authors.initials: C
authors.lastname: Rodrigues
authors.affiliation: UCIBIO/REQUIMTE, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.|CEBIMED/FP-ENAS, Faculdade de Ciências da Saúde, Universidade Fernando Pessoa, Porto, Portugal.
authors.forename: Elisabete
authors.initials: E
authors.lastname: Machado
authors.affiliation: UCIBIO/REQUIMTE, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Pires
authors.affiliation: Centro Hospitalar do Porto - Hospital de Santo António, Porto, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Ramos
authors.affiliation: UCIBIO/REQUIMTE, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors.forename: Ângela
authors.initials: Â
authors.lastname: Novais
authors.affiliation: UCIBIO/REQUIMTE, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors.forename: Luísa
authors.initials: L
authors.lastname: Peixe
mesh_terms: D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000096:biosynthesis*; D005838:Genotype; D006761:Hospitals; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D011174:Portugal / Q000453:epidemiology; D013997:Time Factors; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D029968:Escherichia coli Proteins; C107198:beta-lactamase SHV-12; C055184:beta-lactamase TEM-3; D001618:beta-Lactamases; C000602253:beta-lactamase CTX-M, E coli
keywords: ESBL; MLST; nonclinical reservoirs; phylogenetic group; widespread clonal complexes