Persistent gastrointestinal bleeding due to angiodysplasia of the gut in von Willebrand's disease.

Gastronintestinal vascular dysplasia as a cause of persistently recurring melaena is reported in two patients with von Willebrand's disease. Colonic wall vasculature was affected in one patient, the abnormality being demonstrated both radiologically and at operative hemicolectomy undertaken to control bleeding. Abnormalities in the vasculature of the duodenal and jejunal walls were found in the second patient at operation and necropsy, though not demonstrated by angiography.