Atopic disease in ulcerative colitis and Crohn's disease

Summary Three hundred patients with ulcerative colitis, 200 with Crohn's disease and matched control subjects completed questionnaires about atopic disease. They were asked whether they had ever suffered from asthma, hay fever, allergic rhinitis or eczema; in ulcerative colitis all of these features occurred with twice the frequency, but in Crohn's disease only eczema was more common than in controls.