الملخص
Pyoderma gangrenosum is a painful, chronic, ulcerating skin disease of unknown cause. It commences as an erythematous papulopustule and rapidly evolves to form an area of frank ulceration with undermined, violaceous edges and a bright outer halo of erythema. Diagnosis is clinical, there being no accepted histological diagnostic criteria. An underlying systemic illness is present in more than 50 percent of patients. Pyoderma gangrenosum develops in 0.8~5.0 percent of patients with inflammatory bowel disease, which is the most frequent underlying disease of pyoderma gangrenosum. There is no report of pyoderma gangrenosum associated with Crohn's disease in Korea. We recently experienced two cases of pyoderma gangrenosum, a 52-year old man with Crohn's disease and a 30-year old man with ulcerative colitis. The cases are presented with the review of literature.