Hemostatic alterations in inflammatory bowel disease: response to therapy.

Twelve patients with acute, untreated inflammatory bowel disease (IBD) were followed prospectively for coagulation and platelet function. With no symptomatic coagulopathy, abnormalities were found in all patients. With acute diseases, elevations of fibrinogen (9/12), factor V (8/12), and factor VIII (6/12) were common. Depressions of antithrombin III levels were also observed acutely (8/12). Abnormalities of platelets were both quantitative and qualitative. Thrombocytosis was present (11/12), and abnormalities in the rate and percent platelet aggregation were seen (9/10). During therapy, factors V and VIII, antithrombin III levels, and the quantitative and qualitative platelet abnormalities returned towards normal in direct correlation with sedimentation rate and clinical disease activity.