[Familial Crohn disease].

Authors report two cases of Crohn's disease in a brother and a sister. Female showed first manifestation at 8 years of age. Male started at 12 years. Onset was acute in the girl with ileo-cecal and colonic involvement and extraintestinal manifestations. The boy had an insidious onset with ileal involvement and striking rectal and perianal symptoms. In both cases, clinical course was chronic and relapsing. HLA A and B phenotypes were studied in both patients and their parents. Different factors concerning origin of disease, as well as relationship to other diseases among relatives are discussed.