Inflammatory bowel disease in spouses and their offspring

Background&Aims: The rarity of inflammatory bowel disease (IBD) in both hus band and wife is often given as an argument against an infectious origin, W e registered conjugal instances of IBD in Northern France and in Belgium be tween 1989 and 2000. Methods: Couples were assigned to group A if both part ners had symptoms of IBD before cohabitation, to group B if one spouse had IBD before cohabitation and the other experienced first symptoms afterwards , and to group C if both partners got the disease after cohabitation, Risk of IBD was assessed in their offspring. Results: Thirty conjugal instances were registered, Seventeen were concordant for Crohn's disease and 3 for ul cerative colitis; 10 were mixed. Two belonged to group A, 6 to group B, and 22 to group C, In group C, IBD occurred in the first affected spouse an av erage of 9 years after cohabitation and in the second spouse an average of 8.5 years later. Group C conjugal forms were more frequent than expected by chance (P < 0.02). Fifty-four children were born to 25 couples; among them 9, of whom 4 were siblings, developed Crohn's disease at a median age of 1 5 years. Conclusions: The frequency of conjugal forms of IBD suggests an et iologic role for environmental factors. Offspring of 2 affected parents hav e a high risk of developing IBD.