Pyoderma gangrenosum (PG) is an inflammatory condition of all ages but is most common among 20- to 50-year-old females. Lesions can be located anywhere (most commonly on the lower extremities) and begin as a papulopustule surrounded by erythema. This pustule erodes and expands to form a necrotic ulcer. Similar satellite pustules and ulcers form around the original lesion and can rapidly coalesce into a larger ulcer. The surrounding border is “rolled,” due to the convex elevation, and has a violaceous hue. The ulcers are exquisitely tender to movement and palpation. On the extremities, the ulcers can involve muscles and tendons. Ostomy sites are a common location and can make management very difficult.
Half of cases are idiopathic; the other half are associated with systemic processes such as vascular diseases, inflammatory diseases, malignancies, infections, necrobiosis lipoidica diabeticorum, and trauma. Since the diagnosis is based on exam, dermatopathology, and exclusion of other causes, PG is difficult to confirm, and delayed treatment is common.
Pyoderma Gangrenosum. Rolled and violaceous borders. This lesion can rapidly enlarge and become secondarily infected. (Photo contributor: J. Matthew Hardin, MD.)
Management and Disposition
Appropriate cultures should be obtained. Broad-spectrum antibiotics are indicated for secondary infections. Consult dermatology for biopsy, tissue culture, and initiation of immunosuppressant therapy.
With the large number of ulcers seen in the ED, early diagnosis of PG is difficult and requires a high level of suspicion; think of this in chronic ulcers.
PG is often not diagnosed until late-stage ulcer formation and after multiple failed ulcer treatments and skin grafts. Without identification and control of the underlying disease process, any skin-directed treatment is unlikely to succeed.
Half of PG cases have associated diseases; each case needs a thorough specialty evaluation.
Pyoderma Gangrenosum. Early ulcer formation at the site of an ileostomy dressing. (Photo contributor: Lawrence B. Stack, MD.)