Erythema multiforme in association with active ulcerative colitis and Crohn's disease.

Erythema multiforme of vesiculo-bullous type is described in one patient at the onset of ulcerative colitis and in another during an exacerbation of Crohn's disease. Inflammatory large bowel disease should be once more accepted as a cause of erythema multiforme in its own right, presumably mediated through an immunological reaction.