Identical twins concordant for Crohn's disease

Identical twin adolescent girls developed Crohn's disease within 15 months of each other. Clinical symptoms, growth retardation, barium studies, disease course, and pathologic findings at the time of resection were remarkably similar. Seventeen pairs of twins concordant for Crohn's disease have now been reported, but only four discordant pairs. Such observations lend support to a considerable genetic influence on the development and course of Crohn's disease.