title: A prospective, longitudinal study of central venous catheter-related deep venous thrombosis in boys with hemophilia.
abstract: BACKGROUND
  Central venous catheters (CVCs) are often inserted into boys with hemophilia to secure venous access for factor prophylaxis and immune tolerance induction therapy. Complications associated with CVCs include catheter-related infections, local hemorrhage, and mechanical failure. Less frequently reported is CVC-related deep venous thrombosis (DVT). We conducted a prospective study to determine the frequency and outcome of this complication.
  
  
  METHODS
  All boys (n = 16) with congenital hemophilia A or B with a CVC in place who were registered in the pediatric comprehensive care program at the Hospital for Sick Children, Toronto, were included in the study. They were prospectively assessed by imaging studies and clinical examinations for CVC-related DVT at two time-points, 2 years apart. Each boy was evaluated for inherited hypercoagulability.
  
  
  RESULTS
  Eleven (69%) of the 16 boys had radiological evidence of DVT at the first evaluation and 13/16 (81%) at the second evaluation. In two boys there was improvement in the venogram findings at the second evaluation. None of the CVC-related DVTs completely resolved. Median age at the time of initial insertion of a CVC was 1.0 years (range 0.02-6.7 years). Median duration of CVC placement was 6.4 years (range 3.3-15.5 years). Only 4/13 boys with DVTs had clinical evidence of upper venous system obstruction. Only one boy, who did not develop a DVT, had a low protein C level.
  
  
  CONCLUSIONS
  CVC-related DVTs occur in the majority of boys with hemophilia who have CVCs inserted for a prolonged period of time. Annual screening with imaging is recommended for boys with CVCs in place for >/= 3 years. Consideration should be given to removing CVCs as soon as peripheral venous access is feasible.
authors.affiliation: Division of Hematology/Oncology, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: V E
authors.initials: VE
authors.lastname: Price
authors.forename: M
authors.initials: M
authors.lastname: Carcao
authors.forename: B
authors.initials: B
authors.lastname: Connolly
authors.forename: P
authors.initials: P
authors.lastname: Chait
authors.forename: A
authors.initials: A
authors.lastname: Daneman
authors.forename: M
authors.initials: M
authors.lastname: Temple
authors.forename: A M
authors.initials: AM
authors.lastname: Stain
authors.forename: L
authors.initials: L
authors.lastname: Sung
authors.forename: H
authors.initials: H
authors.lastname: Al-Tralbosi
authors.forename: V S
authors.initials: VS
authors.lastname: Blanchette
mesh_terms: D002405:Catheterization, Central Venous / Q000009:adverse effects*; D002648:Child; D002675:Child, Preschool; D003251:Constriction, Pathologic / Q000209:etiology; D003952:Diagnostic Imaging; D005192:Family Health; D006467:Hemophilia A / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D006801:Humans; D015994:Incidence; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D017410:Practice Guidelines as Topic; D011446:Prospective Studies; D019851:Thrombophilia / Q000235:genetics; D020246:Venous Thrombosis / Q000175:diagnosis / Q000209:etiology*