title: Colonization with antibiotic-resistant gram-negative organisms in a pediatric intensive care unit.
abstract: OBJECTIVE
  To measure the prevalence of colonization with antibiotic-resistant Gram-negative organisms and its association with potential risk factors, including antibiotic exposure, in a pediatric intensive care unit (ICU).
  
  
  METHODS
  Prospective, observational study.
  
  
  METHODS
  A 16-bed tertiary care pediatric ICU.
  
  
  METHODS
  All children admitted to the pediatric ICU for > 24 hrs over a 5-month period.
  
  
  RESULTS
  Two hundred ninety-six patients, approximately half of all patients admitted to the ICU, were enrolled in the study; 236 patients had sufficient data collected for analysis and were prospectively examined for nasopharyngeal and gastrointestinal colonization by antibiotic-resistant Gram-negative organisms (ceftazidime minimal inhibitory concentration of > 16 micrograms/mL, or tobramycin minimal inhibitory concentration > 8 micrograms/mL). Association between colonization and potential predisposing factors including demographics, diagnosis, Pediatric Risk of Mortality (PRISM) score, invasive instrumentation, and prior ICU antibiotic exposure was assessed. More than 20% of patients were found to be colonized with an antibiotic-resistant Gram-negative organism. Examination of the timing of colonization indicated that more than half were identified within 72 hrs of admision. Colonization was associated by unadjusted analysis to prior ICU antibiotic exposure, as well as by factors associated with the severity of illness (PRISM score and invasive instrumentation) and young age. However, when the independence of these factors was tested by logistic regression, prior antibiotic exposure was no longer associated with resistant organism colonization.
  
  
  CONCLUSIONS
  These data suggest that antibiotic-resistant Gram-negative organisms are a significant risk to intensively III children and that in many instances, they are imported into the unit or rapidly acquired from environmental reservoirs. Since risk factors for colonization are multiple, policies confined to antibiotic utilization within the ICU may have fixed, and possibly limited, benefit in their control.
authors.affiliation: Division of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
authors.forename: P
authors.initials: P
authors.lastname: Toltzis
authors.forename: T
authors.initials: T
authors.lastname: Yamashita
authors.forename: L
authors.initials: L
authors.lastname: Vilt
authors.forename: J L
authors.initials: JL
authors.lastname: Blumer
mesh_terms: D002353:Carrier State / Q000382:microbiology*; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000382:microbiology*; D004064:Digestive System / Q000382:microbiology*; D004352:Drug Resistance, Microbial; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology*; D006801:Humans; D017053:Infection Control; D015278:Intensive Care Units, Pediatric; D016015:Logistic Models; D008826:Microbial Sensitivity Tests; D009305:Nasopharynx / Q000382:microbiology*; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D013997:Time Factors