title: Investigation and control of an outbreak of imipenem-resistant Acinetobacter baumannii Infection in a Pediatric Intensive Care Unit.
abstract: BACKGROUND
  This study investigated the clinical details and epidemiology of the imipenem-resistant Acinetobacter baumannii (IRAB) outbreak that occurred at a pediatric intensive care unit (PICU), and describes successful outcome of the implemented infection control measures.
  
  
  METHODS
  With the recognition of 3 clustered cases with IRAB bacteremia at the PICU of Seoul National University Children's Hospital, Korea, from August to September 2010, the following outbreak control strategies were implemented: reinforcement of hand hygiene and contact precautions, investigation of environmental contamination, disinfection of the contaminated environment and medical equipment, active surveillance culture upon PICU admission and isolation of IRAB-positive patients. The clinical and microbiological data were reviewed for A. baumannii positive cases in the PICU from April 2001 to June 2011. Multilocus sequence typing was also performed.
  
  
  RESULTS
  Twenty IRAB-positive cases (bacteremia in 10, pneumonia in 3 and colonizers in 7) were detected from January 2010 to February 2011. Thirteen IRAB-infected patients were all placed on a mechanical ventilator, had central venous catheters, received broad-spectrum antimicrobial treatment and had underlying diseases. Eleven (85%) IRAB-infected patients died probably due to IRAB infection. IRAB grew in 4 samples obtained from sinks and water taps from 38 environmental samples. Multilocus sequence typing analysis revealed 2 sequence types: ST138 (n=16) and its single-locus variant ST92 (n=4). Eleven weeks after the initiation of active surveillance, no further IRAB isolates were identified.
  
  
  CONCLUSIONS
  This study identifies the environmental source of an IRAB outbreak in a PICU and describes successful control of the outbreak with a multicomponent intervention program.
authors.affiliation: Department of Pediatrics, Seoul National University Hospital, and Department of Pediatrics, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Ki Bae
authors.initials: KB
authors.lastname: Hong
authors.forename: Hyang Soon
authors.initials: HS
authors.lastname: Oh
authors.forename: Jeong Suk
authors.initials: JS
authors.lastname: Song
authors.forename: Ji-hee
authors.initials: JH
authors.lastname: Lim
authors.forename: Dong Ki
authors.initials: DK
authors.lastname: Kang
authors.forename: Ihn Suk
authors.initials: IS
authors.lastname: Son
authors.forename: June Dong
authors.initials: JD
authors.lastname: Park
authors.forename: Eui Chong
authors.initials: EC
authors.lastname: Kim
authors.forename: Hoan Jong
authors.initials: HJ
authors.lastname: Lee
authors.forename: Eun Hwa
authors.initials: EH
authors.lastname: Choi
mesh_terms: D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D004196:Disease Outbreaks; D004783:Environmental Microbiology; D005260:Female; D006801:Humans; D015378:Imipenem / Q000494:pharmacology*; D007223:Infant; D007231:Infant, Newborn; D017053:Infection Control / Q000379:methods; D015278:Intensive Care Units, Pediatric; D008297:Male; D056910:Republic of Korea / Q000453:epidemiology; D055815:Young Adult; D018440:beta-Lactam Resistance
chemical_list: D000900:Anti-Bacterial Agents; D015378:Imipenem