Pyoderma gangrenosum

An ulcerating condition of the skin leading to hollowed-out areas (ulcers) with heaped-up borders and a typical appearance. The lesion(s) usually begin as soft raised nodules on the skin which proceed to ulcerate. The ulcers enlarge and the skin at the edge becomes purple-red. The ulcers can become quite large. Pyoderma gangrenosum is thought to be mediated by the immune system, but the exact sequence of events is unknown. It is associated with several other diseases, including ulcerative colitis, Crohn disease, rheumatoid arthritis, leukemia, and cryoglobulinemia. Pyoderma gangrenosum is usually responsive to treatment with corticosteroids.

* * *

pyoderma gan·gre·no·sum -.gaŋ-gri-'nō-səm n a chronic noninfectious condition that is marked by the formation of purplish nodules and pustules which tend to coalesce and form ulcers and that is associated with various underlying systemic or malignant diseases (as leukemia, ulcerative colitis, rheumatoid arthritis, or metastatic adenocarcinoma of the intestine)

* * *

an acute destructive ulcerating process of the skin, especially the legs. It may be associated with ulcerative colitis or Crohn's disease or with rheumatoid arthritis or other forms of arthritis affecting many joints. Treatment is with ciclosporin or with high doses of corticosteroids.

* * *

a rapidly evolving, idiopathic, chronic, debilitating type of neutrophilic dermatosis that usually accompanies a systemic disease such as ulcerative colitis or certain forms of arthritis; characteristics include irregular, boggy, blue-red ulcers with undermined borders surrounding purulent necrotic bases.

Pyoderma gangrenosum in a patient with chronic ulcerative colitis.