title: Factors influencing the acquisition of Stenotrophomonas maltophilia infection in cystic fibrosis patients.
abstract: BACKGROUND
  Stenotrophomonas maltophilia is one of the most common multi-drug resistant organisms causing pulmonary infections in CF patients. It is unknown whether S. maltophilia infection follows the same pattern and shares similar risk factors for acquisition as described for Pseudomonas aeruginosa.
  
  
  METHODS
  We examined all clinical events from 1997 to 2008 in the Toronto CF Database to identify risk factors for the acquisition of S. maltophilia and to define distinct patterns of infection.
  
  
  RESULTS
  We followed 601 patients over 12 years, during which time one quarter of subjects had at least one positive culture for S. maltophilia; the incidence rate was slightly higher in children (11.6/100 person years) compared with adults (10.6/100 person years). Using multi-variable Cox proportional hazards models, steeper rate of FEV1 decline was a significant risk factor for S. maltophilia acquisition, whereas new infections were less likely to occur with greater oral antibiotic use and a history of Burkholderia cepacia complex infection.
  
  
  CONCLUSIONS
  This study illustrates the evolution of S. maltophilia infection over time in a large cohort of adults and children with CF. Younger CF patients, and those with greater lung function decline were at increased risk of S. maltophilia infection. The use of oral antibiotics to maintain lung function may be a way of decreasing the risk of infection. However, the optimal management of CF patients with persistent S. maltophilia infection is not yet known and requires further studies.
authors.affiliation: Division of Respiratory Medicine, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto M5G 1X8, Canada. Electronic address: sanja.stanojevic@sickkids.ca.
authors.forename: Sanja
authors.initials: S
authors.lastname: Stanojevic
authors.forename: Felix
authors.initials: F
authors.lastname: Ratjen
authors.forename: Derek
authors.initials: D
authors.lastname: Stephens
authors.forename: Annie
authors.initials: A
authors.lastname: Lu
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Yau
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Tullis
authors.forename: Valerie
authors.initials: V
authors.lastname: Waters
mesh_terms: D000293:Adolescent; D000328:Adult; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000382:microbiology* / Q000628:therapy; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000628:therapy; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models; D012307:Risk Factors; D020615:Stenotrophomonas maltophilia; D055815:Young Adult
keywords: Epidemiology; Latent class models; Risk factors; Stenotrophomonas maltophilia