Coagulation and fibrinolysis in children, adolescents, and young adults with inflammatory bowel disease

Background: Patients with Crohn's disease and ulcerative colitis have an in creased risk of thromboembolic events. Methods: Data were collected from 24 patients aged 4.5 to 23 years who had inflammatory bowel disease. Platelet count, antithrombin, fibrinogen, proth rombin fragment F1+2, soluble thrombomodulin, tissue plasminogen activator, D-dimer, and plasminogen activator inhibitor-1 antigen were investigated. In addition the response to activated protein C, the factor V R506Q mutatio n, protein C, free protein S antigen, and lipoprotein (a) were analyzed. Th ese data were compared with medical treatment, duration, and disease activi ty, estimated with the Pediatric Crohn's Disease Activity Index or the Clin ical Colitis Activity Index. Results: Forty-five percent of our patients showed an increase in fibrinoge n, 29% in prothrombin fragment F1+2, and 20% in platelet count, plasminogen activator inhibitor-1 antigen, and soluble thrombomodulin. Thrombomodulin was higher in active disease than in inactive disease and in Crohn's diseas e than in ulcerative colitis. Fibrinogen was also higher with Crohn's disea se and tended to be higher in active disease than in ulcerative colitis and inactive disease. Plasminogen activator inhibitor-1 antigen was significan tly higher in patients with Crohn's disease than in those with ulcerative c olitis and was higher in the patient group treated with steroids. Conclusion: As has been shown in adults, young patients with active and ina ctive inflammatory bowel disease were found to have abnormal coagulation an d fibrinolysis. The relevance as a thromboembolic risk factor is discussed.