What is pyoderma gangrenosum and what are the symptoms?

Pyoderma gangrenosum is a skin disorder related to inflammatory bowel disease (IBD). It may first appear at the spot of a minor cut, and looks like a blister, red bump or swelling with pus. Then, the affected skin becomes a purple-colored skin breakdown or ulcer with hazy edges. These type of ulcers tend to be painful and are slow to heal. The ulcers may be single or may group together and are commonly found on legs more often than arms.

What causes pyoderma gangrenosum?

There is no definitive cause for pyoderma gangrenosum, however, it is believed to be an autoimmune condition, as it is related to other autoimmune disorders.

Who gets pyoderma gangrenosum?

Pyoderma is estimated to impact approximately 5 percent of patients with ulcerative colitis and less than 2 percent of patients with Crohn’s disease.  Approximately 50 percent of all pyoderma gangrenosum cases occur in patients with inflammatory bowel disease (IBD).

How is pyoderma gangrenosum related to Crohn’s and ulcerative colitis?

Pyoderma gangrenosum ulcers can be related to a flare, however, in some cases, these can occur even without a flare.

How is pyoderma gangrenosum diagnosed and treated?

To diagnose pyoderma gangrenosum, a dermatologist (or skin doctor) will either:

1. Swab and culture the ulcer
2. Biopsy the ulcer

Small ulcers may be treated with the following:

• Compression bandaging
• Oral antibiotics
• Steroid creams or injections
• Silver sulphadiazine cream or hydrocolloids

Large ulcers are more difficult to treat, as they are often resistant to medication. Some of the more common drugs to treat large pyoderma gangrenosum ulcers are steroids, cyclosporine, cyclophosphamide, methotrexate and tacrolimus ointment.

If you think you have pyoderma gangrenosum as a result of IBD, contact your gastroenterologist as soon as possible.

For additional information on care for IBD at Rush, visit our Inflammatory Bowel Disease Program home page.