title: A prospective survey ofPseudomonas aeruginosacolonization and infection in the intensive care unit.
abstract: BACKGROUND
  Pseudomonas aeruginosa(PA) surveillance may improve empiric antimicrobial therapy, since colonizing strains frequently cause infections. This colonization may be 'endogenous' or 'exogenous', and the source determines infection control measures. We prospectively investigated the sources of PA, the clinical impact of PA colonization upon admission and the dynamics of colonization at different body sites throughout the intensive care unit stay.
  
  
  METHODS
  Intensive care patients were screened on admission and weekly from the pharynx, endotracheal aspirate, rectum and urine. Molecular typing was performed using Enterobacterial Repetitive Intergenic Consensus Polymerase Chain reaction (ERIC-PCR).
  
  
  RESULTS
  Between November 2014 and January 2015, 34 patients were included. Thirteen (38%) were colonized on admission, and were at a higher risk for PA-related clinical infection (Hazard Ratio = 14.6,p= 0.0002). Strains were often patient-specific, site-specific and site-persistent. Sixteen out of 17 (94%) clinical isolates were identical to strains found concurrently or previously on screening cultures from the same patient, and none were unique. Ventilator associated pneumonia-related strains were identical to endotracheal aspirates and pharynx screening (87-75% of cases). No clinical case was found among patients with repeated negative screening.
  
  
  CONCLUSIONS
  PA origin in this non-outbreak setting was mainly 'endogenous' and PA-strains were generally patient- and site-specific, especially in the gastrointestinal tract. While prediction of ventilator associated pneumonia-related PA-strain by screening was fair, the negative predictive value of screening was very high.
authors.affiliation: Head of Infectious diseases unit, Sanz Medical Center, Laniado hospital, Neytanya, Israel ; Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: Regev
authors.initials: R
authors.lastname: Cohen
authors.affiliation: Infectious diseases unit, Sanz Medical Center, Laniado hospital, Netanya, Israel.
authors.forename: Frida
authors.initials: F
authors.lastname: Babushkin
authors.affiliation: Infectious diseases unit, Sanz Medical Center, Laniado hospital, Netanya, Israel.
authors.forename: Shoshana
authors.initials: S
authors.lastname: Cohen
authors.affiliation: Infectious diseases unit, Sanz Medical Center, Laniado hospital, Netanya, Israel.
authors.forename: Marina
authors.initials: M
authors.lastname: Afraimov
authors.affiliation: Medical and Surgical intensive care unit, Sanz Medical Center, Laniado hospital, Netanya, Israel.
authors.forename: Maurice
authors.initials: M
authors.lastname: Shapiro
authors.affiliation: Medical and Surgical intensive care unit, Sanz Medical Center, Laniado hospital, Netanya, Israel.
authors.forename: Martina
authors.initials: M
authors.lastname: Uda
authors.affiliation: National Center of Infection Control, Ministry of Health, Tel Aviv, Israel.
authors.forename: Efrat
authors.initials: E
authors.lastname: Khabra
authors.affiliation: National Center of Infection Control, Ministry of Health, Tel Aviv, Israel ; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Amos
authors.initials: A
authors.lastname: Adler
authors.affiliation: Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel ; Infectious diseases unit Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
authors.forename: Ronen
authors.initials: R
authors.lastname: Ben Ami
authors.affiliation: Microbiology Laboratory, Sanz Medical Center, Laniado hospital, Netanya, Israel.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Paikin
keywords: ERIC-PCR; Endogenous; Infection control; Intensive Care unit; Pseudomonas aeruginosa; Surveillance