Gangrene Gangrene is often associated with World War I soldiers and surgery patients in the days before antibiotics. It's still around today, although modern medicine means people with the condition have a far better outlook than their ancestors.

In this article

What is it? What causes it?

Can it be prevented? What's the treatment?

Any complications?

Gangrene is the death of body tissue in a localised area due to loss of its blood supply. It isn't green - in the parts of the body that are affected, the skin turns black and oozes pus.

Gangrene is thought of as occurring in an arm or a leg, but it can set in wherever there is body tissue. Fingers and toes are the most common parts of the body to be affected, although internal tissue can also turn gangrenous.

Different types

There are two types of gangrene: dry and wet.

Reduction of the blood supply to body tissue causes dry gangrene. A poor blood supply (or none at all) leads to tissue death, and injury is a common reason for this type.

Wet gangrene is caused by toxin-producing bacteria that destroy body tissue. Clostridium bacteria produce lethal toxins in a wound, known as gas gangrene. The skin looks as though there are bubbles underneath, and pus and infection spread rapidly.

The most common causes of gangrene are conditions and activities that may block or destroy the blood supply to body tissue, such as:

• Injury
• Diabetes
• Smoking
• Thrombosis
• Frostbite
• Severe burns
• Drinking excessive alcohol

Old age also increases the risk of gangrene.

People at risk of developing gangrene should exercise their fingers and toes regularly and wear well-fitting shoes. It's vital to carry out scrupulous foot care, including nail-cutting by a chiropodist.

Dead tissue is surgically removed, then steps are taken to address the condition that led to gangrene. For example, anticoagulants are used to prevent blood from clotting, and surgery restores blood supply to the affected part of the body. It’s important to prevent infection by keeping the area clean and, if infection develops, antibiotics will be necessary.

Patients need plenty of rest and should take prescribed pain relievers. It's especially important to keep wounds clean - previous generations used maggots, but antiseptic dressings are now used, although maggots are making a comeback.

Sometimes, hyperbaric oxygen treatment is recommended.

Provided gangrene is diagnosed early and treated swiftly, many people make a full recovery without the need for amputation. As always, prevention is better than cure, so keep wounds clean and sterile to prevent gangrene setting in.

Dead body tissue must be removed to prevent infection spreading to surrounding areas, so sometimes gangrenous fingers or toes are amputated.

In extreme cases, where gangrene has spread and isn't responding to other treatments, amputation of the limb is necessary. Gas gangrene is the most dangerous form and must be treated quickly.

This article was last medically reviewed by Dr Rob Hicks in April 2008