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Pyoderma Gangrenosum


The Manual's Editorial Staff

Last full review/revision Jan 2021| Content last modified Jan 2021
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What is pyoderma gangrenosum?

"Pyoderma" means a skin inflammation (swelling). "Gangrenosum" means skin ulcers with the death of tissue.

Pyoderma gangrenosum is a skin disease in which you get large sores on your skin, usually on your legs.

  • It happens most often in people ages 25 to 55

  • Doctors don't know what causes it, but it often happens in people who have another health problem, such as inflammatory bowel disease

  • Sometimes it happens to skin that's recently been injured

  • You get small bumps or blisters that become open sores

  • Treatments include dressings, creams, and medicines

What causes pyoderma gangrenosum?

Doctors don't know exactly what causes pyoderma gangrenosum, but they think it involves a problem with your immune system. Pyoderma gangrenosum is more common in people who have certain other health problems, such as:

What are the symptoms of pyoderma gangrenosum?

Symptoms of pyoderma gangrenosum include:

  • A red bump or blister that becomes an open, painful sore that grows quickly

  • Raised area around the sore that is dark or purple

  • Fever

  • General feeling of illness

Sores from pyoderma gangrenosum can get worse from:

  • Biopsy (taking out part of the tissue to look at under a microscope)

  • Cleaning dead skin from the wound (called debridement)—although debridement usually helps wounds heal, debriding the sores of pyoderma gangrenosum makes them worse instead of better

Symptoms can sometimes spread to other areas, such as your belly area, bones, lungs, or muscles.

How can doctors tell if I have pyoderma gangrenosum?

Doctors can usually tell if you have pyoderma gangrenosum by looking at the sores.

How do doctors treat pyoderma gangrenosum?

Doctors treat pyoderma gangrenosum using:

  • Dressings to protect your skin

  • Corticosteroids

  • Sometimes medicine to calm down your immune system

Doctors don't usually do surgery because it makes the sores worse.

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