title: The factor V Leiden mutation increases the risk of venous thrombosis in patients with inflammatory bowel disease.
abstract: OBJECTIVE
  Thromboembolic disease is a significant cause of morbidity and mortality in patients with inflammatory bowel disease (IBD). The aim of this study was to determine the incidence and possible association of the factor V Leiden mutation with the development of thrombosis in patients with IBD.
  
  
  METHODS
  This retrospective study included 11 patients with IBD and arterial or venous thrombosis and 51 patients with IBD and no history of thrombosis who were matched for age, sex, ethnic/racial origin, and type of IBD (controls). The presence of the factor V Leiden mutation was determined by coagulation assay and confirmed by a polymerase chain reaction method.
  
  
  RESULTS
  Four of 11 IBD patients (36%) with thrombosis and 2 of 51 IBD controls (4%) were heterozygotes for the factor V Leiden mutation (relative risk, 14.00; 95% confidence interval, 1.55-169.25; P = 0.009, Fisher exact test). All thrombotic events in the patients with activated protein C resistance were venous with a calculated prevalence of 50% (4 of 8 patients) and a relative risk of venous thrombosis in IBD patients with factor V Leiden of 23 (95% confidence interval, 2-294; P = 0.005).
  
  
  CONCLUSIONS
  In patients with IBD, inheritance of the factor V Leiden mutation results in a significant increased risk of venous thrombosis.
authors.affiliation: Division of Hematology, Department of Medicine, University of Southern California School of Medicine, Los Angeles, California, USA. liebman@hsc.usc.edu
authors.forename: H A
authors.initials: HA
authors.lastname: Liebman
authors.forename: N
authors.initials: N
authors.lastname: Kashani
authors.forename: D
authors.initials: D
authors.lastname: Sutherland
authors.forename: W
authors.initials: W
authors.lastname: McGehee
authors.forename: A L
authors.initials: AL
authors.lastname: Kam
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004351:Drug Resistance; D005165:Factor V / Q000235:genetics*; D005260:Female; D006579:Heterozygote; D006801:Humans; D015994:Incidence; D015212:Inflammatory Bowel Diseases / Q000150:complications* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000502:physiology*; D011486:Protein C / Q000494:pharmacology / Q000502:physiology; D012189:Retrospective Studies; D012307:Risk Factors; D013924:Thrombophlebitis / Q000453:epidemiology / Q000209:etiology*
chemical_list: D011486:Protein C; C095381:factor V Leiden; D005165:Factor V