Pyoderma gangrenosum is an uncommon ulcerative cutaneous condition of uncertain etiology. It is a disease that causes tissue to become necrotic, causing deep ulcers that usually occur on the legs. When they occur, they can lead to chronic wounds. PG usually starts suddenly -- often at the site of a minor injury -- as a small pustule, red bump or blood blister. The size and depth of the ulcerations vary greatly, and they are often extremely painful. In approximately 50 percent of cases, PG occurs secondary to another disorder such as inflammatory bowel disease. The skin breaks down, resulting in an ulcer, or ulcers, which may deepen and widen rapidly. The ulcers can become quite large. Some patients will have accompanying fever, malaise, muscle and joint pains. Often the lesion heals leaving a cribriform scar. It tends to occur on the lower extremities, trunk, and occasionally on the head and neck. The diagnosis is based on clinical features and excluding other causes of skin ulcers, as it does not have characteristic histopathology or laboratory findings. Pyoderma gangrenosum is rare.

Pyoderma gangrenosum is thought to be mediated by the immune system, but the exact sequence of events is unknown. It affects approximately 1 person in 100,000 in the population. About half the people with pyoderma gangrenosum have an underlying chronic health condition. Patients with PG may have involvement of other organ systems that manifests as sterile neutrophilic abscesses. Culture-negative pulmonary infiltrates are the most common extracutaneous manifestation. The lesion usually begin as soft raised nodules on the skin which proceed to ulcerate. The ulcers enlarge and the skin at the edge becomes purple-red. PG generally responds well to treatment; however, it sometimes recurs or causes scarring.

Causes of Pyoderma gangrenosum

The common causes and risk factor's of Pyoderma gangrenosum include the following:

There's no specific cause of pyoderma gangrenosum.

Rheumatoid arthritis.

Ulcerative colitis.

Symptoms of Pyoderma gangrenosum

Some sign and symptoms related to Pyoderma gangrenosum are as follows:

One or more small, red bumps on the skin.

Crampy abdominal (belly area) pain.

Swollen gums.

Eye inflammation.

Achy joints or pain in the bones and tiredness.

Lack of appetite.

Persistent, watery diarrhea.

Fatigue.

Tenesmus (pain with passing stool).

Treatment of Pyoderma gangrenosum

Here is list of the methods for treating Pyoderma gangrenosum:

Often conventional antibiotics such as flucloxacillin are prescribed prior to making the correct diagnosis.

Corticosteroids help relieve inflammation. Usually pyoderma gangrenosum is treatable with oral corticosteroids, but in some cases the type that you can spread on your skin (topical) may be used.

Intravenous therapies include pulsed methylprednisolone, pulsed cyclophosphamide, infliximab, and intravenous immune globulin.

Tacrolimus ointment is an immune modulating drug that inhibits calcineurin and has been reported to improve pyoderma gangrenosum.

Immunomodulators such as azathioprine or 6-mercaptopurine help reduce the need for corticosteroids and can help heal some fistulas.

Some persons with this disease may need surgery to remove the entire large intestine (colon) with or without the rectum.

Other therapy includes hyperbaric oxygen.