title: Cystic fibrosis as a risk factor for recurrent venous thrombosis at a pediatric tertiary care hospital.
abstract: OBJECTIVE
  To evaluate risk factors for recurrent thrombosis in pediatric patients.
  
  
  METHODS
  This prospective observational cohort study enrolled 120 patients with acute venous thromboembolism from January 2003 to April 2005. Data collection included medical and family history, radiologic and laboratory studies, therapy, and follow-up.
  
  
  RESULTS
  The overall prevalence of recurrent thrombosis in our cohort was 19/120 (15.8%). Patients with recurrence were older, with a median age of 14.8 years (range 2 weeks-23.6 years), compared with 10.1 years (range newborn 23.4 years) in patients without recurrence (P = .03). Six of the 19 patients with recurrent thrombosis had cystic fibrosis (CF), compared with 0/101 without recurrence (P < .001). Five of these 6 patients were colonized with Burkholderia cepacia in their sputum. Central venous catheters were associated with most, but not all, of the thromboses in patients with CF.
  
  
  CONCLUSIONS
  In this study, patients with CF had a high risk of recurrent venous thrombosis, as well as a high prevalence of colonization with B cepacia. The cause of this risk has not been defined. This observation may have important implications for thromboprophylaxis, particularly in the setting of central venous catheters.
authors.affiliation: Division of Hematology, The Children's Hospital of Philadelphia, Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia 19104-4399, USA. raffini@email.chop.edu
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: Raffini
authors.forename: Deepti
authors.initials: D
authors.lastname: Raybagkar
authors.forename: Marilyn S
authors.initials: MS
authors.lastname: Blumenstein
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Rubenstein
authors.forename: Catherine S
authors.initials: CS
authors.lastname: Manno
mesh_terms: D000293:Adolescent; D000328:Adult; D016956:Burkholderia cepacia; D002405:Catheterization, Central Venous; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000150:complications* / Q000382:microbiology; D005260:Female; D006776:Hospitals, Pediatric; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D013183:Sputum / Q000382:microbiology; D020246:Venous Thrombosis / Q000209:etiology* / Q000382:microbiology