Pyoderma gangrenosum

The main symptom of pyoderma gangrenosum is a large, painful ulcer on your skin.

It usually starts as a small bump, spot or blood blister that gets bigger quickly and turns into an ulcer.

Sometimes you may have more than 1 ulcer.

Pyoderma gangrenosum ulcers:

• usually appear on the legs or chest
• may also appear around a cut or graze, a stoma (where part of your bowel is brought through an opening made in your tummy), or cuts from surgery
• may leak fluid

On white skin, the pyoderma gangrenosum ulcer will often be blue or purple around the edge.

On brown or black skin, the skin around the pyoderma gangrenosum ulcer may be darker than the rest of the skin.

Other symptoms include:

• stiff joints
• aching and painful muscles
• a high temperature

• you have a skin ulcer that's not getting better

How pyoderma gangrenosum is treated depends on how severe it is.

It can take a long time for the ulcers to heal and you may have scars.

Treatment may include:

• creams or ointments
• bandages and dressings to protect the ulcer
• medicines to calm or control your body's immune system
• steroid injections
• antibiotics

Rarely, you may need surgery to remove the ulcers.

It's not always clear what causes pyoderma gangrenosum. It may be an autoimmune disease, where the body's natural defence system (immune system) attacks healthy parts of your body.

It can also sometimes happen after an injury to the skin.

You may be more likely to get pyoderma gangrenosum if you have certain conditions, including:

• inflammatory bowel disease, such as ulcerative colitis or Crohn's disease
• rheumatoid arthritis
• certain blood disorders, such as myelodysplastic syndrome
• hepatitis
• Behçet's disease

You may also be more likely to get pyoderma gangrenosum if you take certain medicines.

The main symptom of pyoderma gangrenosum is a large, painful ulcer on your skin. You may have more than 1 and they usually appear on the chest or leg.

Pyoderma gangrenosum can be treated with creams, steroids, injections or antibiotics.

Pyoderma gangrenosum often has no cause. You may be more likely to get it if you have conditions like arthritis and inflammatory bowel disease.