The term "pyoderma gangrenosum" was introduced by Brunsting, Goeckerman, and O'Leary1 in 1930. It designates an ulcerative cutaneous eruption which is extremely persistent and resistant to therapy.
The lesions may be multiple or there may be one large ulceration. Although gangrene is not always apparent, the ulceration usually spreads rapidly, often involving skin and subcutaneous tissue. The eruption may also consist of vegetating pyogenic lesions which are persistent and recurring. It is frequently associated with visceral disease, most frequently ulcerative colitis, or with empyema or bronchitis, or it may follow operation for appendicitis, cholecystitis, or any other abdominal surgical condition. It may also be associated with arthritis. In children it may follow some of the exanthemata.2,3 However, in many cases no such visceral disease or preceding illness is present. It is assumed that the cutaneous involvement is an expression of low resistance of