Pyoderma gangrenosum is a rare skin condition thatcauses painful ulcers. It's usually treatable, but may take some time to heal and may leave some scarring.

It usually suddenly starts as a small pimple, red bump or blood blister. The skin then breaks down into a painful ulcer with a purple or blue edge, whichmay ooze fluid.

The ulcer can rapidly get bigger and deeper, and several may develop in the area. If the ulcer gets infected, you may also feel unwell and develop a high temperature (fever).

Pyoderma gangrenosumusually affects thelegs, although it can affect any area of skin, including around the head and neck, arms and genitals. Occasionally, it develops around the site of an injury or surgical wound (see what causes pyoderma gangrenosum? below).

Despite the similar-sounding name,pyoderma gangrenosum is not related to Gangrene .

Content supplied by the NHS Website

Medically Reviewed by a doctor on 16 Jan 2017