title: Evolution of antibiotic multiresistance in Escherichia coli and Klebsiella pneumoniae isolates from urinary tract infections: A 12-year analysis (2003-2014).
abstract: BACKGROUND
  The aim of this study was to identify multi-drug resistance (MDR) in the main enterobacteriaceae implicated in urinary tract infections (Escherichia coli and Klebsiella pneumoniae) from both, community and hospitalized patients and to analyze the evolution over a 12-year period.
  
  
  METHODS
  Microb Dynamic software was used to analyze the microbiology laboratory database and a chi square test was applied to compare differences in group proportions and to determine the linear trend over 12 years in three different periods: 2003-2006, 2007-2010, 2011-2014. We chose amoxicillin, gentamicin, ciprofloxacin and trimethoprim-sulphamethoxazole as MDR markers.
  
  
  RESULTS
  A total of 39,980 positive urine samples were analyzed, 34,564 (3786 from hospitalized patients and 30,778 from non-hospitalized patients) E. coli isolates, and 5,422 (774 from hospitalized patients and 4,648 from non-hospitalized patients) K. pneumoniae isolates. The prevalence of UTI due to MDR E. coli and MDR K. pneumoniae significantly increased in the period studied, both in hospitalized and outpatients. A higher percentage of MDR E. coli (5.89% in 2007-2010 versus 8.18% in 2011-2014) and MDR K. pneumoniae (2.38% in 2007-2010 versus 9.35% in 2011-2014) was evident and maintained constant over time in hospitalized patients in comparison to non-hospitalized ones. Infection due to MDR ESBL-producing E. coli and K. pneumoniae increased significantly during the last 8 years in both, hospitalized (20% versus 38% and 66.8% versus 82.6%, respectively) and non-hospitalized patients (18.2% versus 23.6% and 51% versus 74.6%, respectively).
  
  
  CONCLUSIONS
  This study includes data of a large sample size of urinary strains isolated over a 12 year period and demonstrates that MDR is an increasing phenomenon of particular importance in the main UTI-causing species.
authors.affiliation: Servicio de Microbiología, Hospital Universitario de Getafe, Getafe, Madrid, Spain.
authors.forename: David M
authors.initials: DM
authors.lastname: Arana
authors.affiliation: Facultad de Ciencias Biomédicas, Universidad Europea de Madrid, Villaviciosa de Odón, Madrid, Spain.
authors.forename: Margarita
authors.initials: M
authors.lastname: Rubio
authors.affiliation: Servicio de Microbiología, Hospital Universitario de Getafe, Getafe, Madrid, Spain; Facultad de Ciencias Biomédicas, Universidad Europea de Madrid, Villaviciosa de Odón, Madrid, Spain. Electronic address: nachoalos@telefonica.net.
authors.forename: Juan-Ignacio
authors.initials: JI
authors.lastname: Alós
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology*; D006785:Hospitals, University / Q000706:statistics & numerical data; D006786:Hospitals, Urban / Q000706:statistics & numerical data; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D009017:Morbidity / Q000639:trends; D013030:Spain / Q000453:epidemiology; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000382:microbiology*; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D001618:beta-Lactamases
keywords: Escherichia coli; Klebsiella pneumoniae; Multidrug resistance; Multirresistencia a antibióticos; Uropathogens; Uropatógenos