title: Outbreak of multi-drug resistant Pseudomonas aeruginosa bloodstream infection in the haematology unit of a South African Academic Hospital.
abstract: OBJECTIVE
  To describe an outbreak of multi-resistant Pseudomonas aeruginosa bloodstream infections (MRPA-BSI) that occurred in the haematology ward of a tertiary academic hospital in Cape Town, South Africa, and determine risk factors for acquisition of MRPA-BSI.
  
  
  METHODS
  The outbreak investigation included a search for additional cases, review of patient records, environmental and staff screening, molecular typing using pulsed-field gel electrophoresis (PFGE) and Multi-locus sequencing (MLST) and a retrospective case-control study.
  
  
  RESULTS
  Ten MRPA-BSI cases occurred in the haematology ward between January 2010 and January 2011. The case fatality rate was 80%. Staff screening specimens were negative for MRPA and an environmental source was not identified. PFGE showed that 9/10 isolates were related. MLST showed that 3 of these 9 isolates belonged to Sequence type (ST) 233 while the unrelated isolate belonged to ST260.
  
  
  CONCLUSIONS
  We have described an outbreak of MRPA-BSI occurring over an extended period of time among neutropenic haematology patients. Molecular typing confirms that the outbreak was predominantly due to a single strain. The source of the outbreak was not identified, but the outbreak appears to have been controlled following intensive infection control measures.
authors.affiliation: Centre for Tropical, Opportunistic and Hospital Infections, National Institute for Communicable Diseases, Johannesburg, South Africa.
authors.forename: Maanda
authors.initials: M
authors.lastname: Mudau
authors.forename: Rachael
authors.initials: R
authors.lastname: Jacobson
authors.forename: Nadia
authors.initials: N
authors.lastname: Minenza
authors.forename: Lazarus
authors.initials: L
authors.lastname: Kuonza
authors.forename: Vida
authors.initials: V
authors.lastname: Morris
authors.forename: Heather
authors.initials: H
authors.lastname: Engelbrecht
authors.forename: Mark P
authors.initials: MP
authors.lastname: Nicol
authors.forename: Colleen
authors.initials: C
authors.lastname: Bamford
mesh_terms: D000046:Academic Medical Centers; D000293:Adolescent; D000328:Adult; D016470:Bacteremia; D016022:Case-Control Studies; D003428:Cross Infection; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D005260:Female; D006757:Hospital Units; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D011552:Pseudomonas Infections / Q000453:epidemiology* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000187:drug effects / Q000235:genetics; D012189:Retrospective Studies; D012307:Risk Factors; D013019:South Africa; D055815:Young Adult