title: [Trends in the prevalence of extended-spectrum beta-lactamase-producing gram-negative bacilli in a teaching hospital in Madrid, Spain].
abstract: OBJECTIVE
  The pprevalence of extended-spectrum beta-lactamase (ESBL) producing gram-negative bacilli has increased in recent years. The aim of this study is to estimate the prevalence of infection/colonization due to theses microorganisms per 100 admissions and its trend during the period 2007-2010.
  
  
  METHODS
  Prospective observational study of all patients admitted from January 2007 to December 2010 infected or colonized with ESBL-producing gram-negative bacilli at Hospital Universitario Ramón y Cajal. The prevalence of infection/colonization of ESBL-producing gram-negative rods was calculated according to the recommendations for metrics for multidrug-resistant organisms in healthcare settings of The Society for Healthcare Epidemiology of America and the Healthcare Infection Control Practices Advisory Committee. To analyse trends, Poisson regression was used (Joinpoint Regression Program Version 3.4.3, U.S. National Institutes of Health).
  
  
  RESULTS
  Through the study period there was an upward trend of prevalence of all the ESBL-producing gram-negative bacilli. The Poisson trend analysis indentified a significant inflection point in August 2009 (p=0.014).
  
  
  CONCLUSIONS
  The inflection point in the prevalence of the ESBL-producing gram-negative bacilli trend can be explained by a slowdown in the prevalence of some microorganisms such as ESBL-producing Klebsiella pneumoniae.
authors.affiliation: Servicio de Medicina Preventiva, Hospital Universitario Ramón y Cajal, Madrid, España. abelernesto.gonzalez@salud.madrid.org
authors.forename: Abel Ernesto
authors.initials: AE
authors.lastname: González-Vélez
authors.forename: Cristina
authors.initials: C
authors.lastname: Díaz-Agero Pérez
authors.forename: Ana
authors.initials: A
authors.lastname: Robustillo-Rodela
authors.forename: María José
authors.initials: MJ
authors.lastname: Pita-López
authors.forename: Ana María
authors.initials: AM
authors.lastname: Cornejo-Gutiérrez
authors.forename: Pelayo
authors.initials: P
authors.lastname: Pedrero-Pérez
authors.forename: Vicente
authors.initials: V
authors.lastname: Monge-Jodra
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001426:Bacterial Proteins / Q000032:analysis* / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology; D029968:Escherichia coli Proteins / Q000032:analysis / Q000235:genetics; D005260:Female; D006090:Gram-Negative Bacteria / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D006785:Hospitals, University / Q000706:statistics & numerical data*; D006786:Hospitals, Urban / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D016012:Poisson Distribution; D015995:Prevalence; D011446:Prospective Studies; D013030:Spain / Q000453:epidemiology; D013045:Species Specificity; D055815:Young Adult; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000032:analysis* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D001618:beta-Lactamases