Crohn's disease is a chronic inflammatory bowel disease which may have distinctive mucocutaneous manifestations. Included in this group are perianal, peristomal, and perifistular ulceration, as well as granulomatous cutaneous inflammation separate from gastrointestinal tract openings (metastatic Crohn's disease).
In the oral cavity, both ulcerations and granulomatous nodules may occur. Malabsorption of nutrients may lead to several changes, including an acrodermatitis enteropathica–like syndrome secondary to zinc deficiency. Patients with Crohn's disease may also have pyoderma gangrenosum, erythema nodosum, cutaneous vasculitis, and other less specific changes.