Pyoderma Gangrenosum

Pyoderma Gangrenosum

What is pyoderma gangrenosum?

Pyoderma gangrenosum is a rare treatable cause of skin ulceration. It is not a type of gangrene. Pyoderma gangrenosum is not contagious and cannot be transferred from person to person.

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What does it look like

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Can it appear anywhere?


What causes pyoderma gangrenosum?

Approximately 50% of people with pyoderma gangrenosum have no known cause for it. In some cases it may start after trauma to the skin. Other cases are associated with an underlying medical condition such as inflammatory bowel disease, arthritis or certain blood disorders. It is important to know that having pyoderma gangrenosum does not mean that you have these diseases but your specialist or doctor will consider and exclude these.

What does pyoderma gangrenosum look like?

Pyoderma gangrenosum usually occurs in young to middle-aged adults. The appearance of the condition may vary. It may start as a small pimple, red bump, pustule or blood-blister. The skin usually breaks down to form an ulcer which often oozes fluid. The ulcer can enlarge rapidly. The edge of the ulcer may lookpurplish. The most common place for pyoderma gangrenosum to occur is on the legs, but it may occur on any part of the skin. Sometimes it may occur around the site of a stoma (e.g. colostomy), or in a surgical wound.

What are the symptoms of pyoderma gangrenosum?

There is usually a single large ulcer. Occasionally there may be multiple ulcers. Ulcers may become infected, oozing fluid or pus. Pain or discomfort from the ulcer is common. Pyoderma gangrenosum is not a skin cancer and does not lead to cancer.

How is pyoderma gangrenosum diagnosed?

There is no specific blood test for pyoderma gangrenosum. Certain conditions such as venous ulcers, blood vessel or skin inflammation, infection, injury, and cancer can look like pyoderma gangrenosum. Your doctor may take a sample of skin (biopsy) to examine under the microscope in a laboratory to confirm the diagnosis. The wound may be swabbed to rule out infection. Your doctor may also consider blood tests or other tests to rule out any conditions that might occur with pyoderma gangrenosum.

It is not hereditary and is not passed from parents to their children.

How can pyoderma gangrenosum be treated?

Pyoderma gangrenosum is often difficult to treat and may take some time to heal. More than one treatment may need to be tried. Skin grafts and surgery are not treatment options as they often fail and may cause enlargement of the ulcer.

Treatment may be divided into local treatment (topical) or systemic.  The specific treatment depends on the severity of the disease.

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This information is provided by the British Association of Dermatologists.

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