The cause and pathogenesis of ulcerative colitis and regional enteritis of the gastrointestinal (GI) tract remain obscure, despite increasing clinical familiarity with these disorders. These two diseases share similar epidemiologic, demographic, clinical, extraintestinal, immunologic, and genetic features, as might be expected of two pathogenetically related disorders. Whether they represent two intestinal-colonic responses to a common cause or actually are unrelated disorders, reflecting the limited repertoire of the bowel, is not yet known. The similar clinical features of inflammatory bowel disease (IBD) in many areas of the world, despite differing ethnic populations, environmental circumstances, dietary habits, and sociocultural customs, is also noteworthy. The rising worldwide incidence of regional enteritis suggests the involvement of environmental agents (eg, pollutants or transmissible agents) not unique to any single geographic region.
Attempts to clarify the nature of ulcerative colitis and regional enteritis on the basis of the discernible tissue and cellular reactions, as disclosed by
Kirsner JB. The `Idiopathic' Inflammatory Bowel DiseasesTheir Cause and Pathogenesis. Arch Dermatol. 1982;118(4):280-282. doi:10.1001/archderm.1982.01650160070029