title: Successful implementation of infection control strategies prevents P. aeruginosa transmission among cystic fibrosis patients inside the hospital.
abstract: BACKGROUND
  The aim of this study was to characterise the epidemiology of P. aeruginosa isolated from cystic fibrosis (CF) patients at the Vienna General Hospital (VGH) by molecular genetic fingerprinting in order to understand transmission ways and to evaluate the established infection control protocols.
  
  
  METHODS
  The outpatient clinic for CF patients at the VGH cares for children and adolescents up to the age of 18 years. Among an average of 139 patients cared for at the clinic, 41 were tested positive for P. aeruginosa during the study period. Fifty P. aeruginosa isolates, obtained between August 2010 and March 2012 from routine examinations of CF patients, were subject to molecular characterization using the DiversiLab(®) method.
  
  
  RESULTS
  42 distinguishable molecular-biological patterns were identified, 7 of which were found multiple times. 40 out of 42 genotypes were retrieved from single patients only, while two patterns were present in two patients each. Nine patients presented with two or more phenotypically diverse P. aeruginosa isolates. In five of these cases the retrieved isolates belonged to the same genotype.
  
  
  CONCLUSIONS
  The broad genetic heterogeneity of P. aeruginosa in the studied patient population suggests that the majority of CF patients cared for at the VGH acquire P. aeruginosa from environmental sources. It may be concluded that implemented infection control guidelines have been successful in preventing nosocomial transmission of P. aeruginosa among CF patients within the VGH and patient-to-patient transmission outside the hospital. Chronic polyclonal infection/colonization was rare in the study population.
authors.affiliation: Department for Hospital Hygiene and Infecion Control, Medical University of Vienna, Vienna General Hospital, Wien, Austria.
authors.forename: Benedikt
authors.initials: B
authors.lastname: Matt
authors.affiliation: Clinical Department for Clinical Microbiology, Medical University of Vienna, Vienna General Hospital, Wien, Austria.
authors.forename: Dieter
authors.initials: D
authors.lastname: Mitteregger
authors.affiliation: Department of Paediatrics and Adolescent Medicine, Medical University of Vienna, Vienna General Hospital, Wien, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Renner
authors.affiliation: Department for Hospital Hygiene and Infecion Control, Medical University of Vienna, Vienna General Hospital, Wien, Austria.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Presterl
authors.affiliation: Department for Hospital Hygiene and Infecion Control, Medical University of Vienna, Vienna General Hospital, Wien, Austria.
authors.forename: Ojan
authors.initials: O
authors.lastname: Assadian
authors.affiliation: Department for Hospital Hygiene and Infecion Control, Medical University of Vienna, Vienna General Hospital, Wien, Austria.
authors.forename: Magda
authors.initials: M
authors.lastname: Diab-Elschahawi
keywords: Pseudomonas aeruginosa; cystic fibrosis; hospital hygiene; repetitive sequence-based PCR