[Massive hemorrhage in Crohn disease--a rare complication].

Acute massive intestinal bleeding is a rare complication in Crohn's disease. Its occurrence has been quoted between one and 1.4 per cent in the literature, and it has been about two per cent among the authors' own patients. Reported in this paper are three of these cases with acute bleeding as indicator of the disease. In one of them the presence of Crohn's disease had been known for some time. In the second bleeding occurred as a complication to toxic megacolon. In the third patient bleeding was the first manifestation of Crohn's disease.