title: Impact of microbial ecology on accuracy of surveillance cultures to predict multidrug resistant microorganisms causing ventilator-associated pneumonia.
abstract: OBJECTIVE
  The objective of this study was to assess surveillance cultures (SC) prediction accuracy in two periods and settings of the same Department with a different microbiological epidemiology (high and low prevalence of multi-drug resistant microorganisms (MDRM)).
  
  
  METHODS
  Prospective and observational study. SC were obtained twice a week in consecutive mechanically ventilated patients. Patients fulfilling VAP criteria were analyzed.
  
  
  RESULTS
  440 patients were followed up, 71 patients had VAP (50 in period I and 21 in period II). MDRM causing VAP were more prevalent in the first period (48% vs. 19%; p = 0.033). The rate of empirical appropriate treatment in period I was lower than in period II (52% vs.76%; p = 0.031). SC prediction accuracy was similar in the two periods (80% vs. 81%; p = 0.744). However, if antibiotic treatment had been guided by SC, the percentage of appropriate treatment would have increased by 28% in the first period but only by 5% in the second; p = 0.024.
  
  
  CONCLUSIONS
  SC were able to predict VAP etiology in 80% of cases regardless the prevalence of MDRM. However, the potential benefit of SC in terms of appropriate empirical treatment could be only observed when MDRM were prevalent.
authors.affiliation: Intensive Care Medicine, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Lopez-Ferraz
authors.affiliation: Intensive Care Medicine, Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CibeRes, CB06/06/0028), Instituto de Salud Carlos III, Spain. Electronic address: ramirez_pau@gva.es.
authors.forename: Paula
authors.initials: P
authors.lastname: Ramírez
authors.affiliation: Intensive Care Medicine, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Monica
authors.initials: M
authors.lastname: Gordon
authors.affiliation: Intensive Care Medicine, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Veronica
authors.initials: V
authors.lastname: Marti
authors.affiliation: Intensive Care Medicine, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Gil-Perotin
authors.affiliation: Department of Microbiology, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Gonzalez
authors.affiliation: Intensive Care Medicine, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Villarreal
authors.affiliation: Intensive Care Medicine, Hospital del Mar, Barcelona, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Alvarez-Lerma
authors.affiliation: Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CibeRes, CB06/06/0028), Instituto de Salud Carlos III, Spain; Department of Pneumology, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Rosario
authors.initials: R
authors.lastname: Menendez
authors.affiliation: Intensive Care Medicine, Hospital Universitari i Politècnic La Fe, Valencia, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Bonastre
authors.affiliation: Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CibeRes, CB06/06/0028), Instituto de Salud Carlos III, Spain; Department of Pneumology, Hospital Clinic, Barcelona, Spain.
authors.forename: Antoni
authors.initials: A
authors.lastname: Torres
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification; D016009:Chi-Square Distribution; D024901:Drug Resistance, Multiple, Bacterial; D004783:Environmental Microbiology; D005260:Female; D006801:Humans; D017053:Infection Control / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000453:epidemiology / Q000382:microbiology*; D053717:Pneumonia, Ventilator-Associated / Q000453:epidemiology / Q000382:microbiology*; D011446:Prospective Studies; D013030:Spain / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents
keywords: Acinetobacter baumannii; Appropriate treatment; Multidrug resistant microorganism; Pseudomonas aeruginosa; Surveillance cultures; Ventilator-associated pneumonia