Gangrene 

Gangrene is a serious condition in which a loss of blood supply causes tissue to die. It can affect any part of the body but typically starts in the toes, feet, fingers and hands (the extremities).

Gangrene can occur as a result of an injury, infection or a long-term condition that affects blood circulation.

Symptoms of gangrene include:

• the affected area of tissue changes colour, such as turning red to brown to black
• a loss of sensation in the affected area, or the area of tissue becomes extremely painful
• the affected tissue develops black blisters and begins producing a foul-smelling pus

Read more about symptoms of gangrene.

Treatment

You should seek immediate medical advice if you think you have gangrene. The sooner the condition is treated the better the outcomes usually are.

Treatment options for gangrene include:

• using surgery to remove damaged tissue (known as debridement)
• using antibiotics to treat any underlying infection

In more severe cases it may be necessary to remove an entire body part such as a toe, foot, or lower leg. This is known as amputation.

Read more about the treatment of gangrene.

What causes gangrene?

Types of gangrene

The two most common types of gangrene are:

• dry gangrene
• wet gangrene

Dry gangrene

Dry gangrene is usually caused by a health condition disrupting the flow of blood to certain body parts; most commonly the toes and feet.

Conditions associated with dry gangrene include:

• type 1 and type 2 diabetes – high levels of blood sugar associated with these conditions can damage the blood vessels
• atherosclerosis – where arteries narrow and become clogged with a fatty substance known as plaque (risk factors for atherosclerosis include smoking and having high cholesterol levels)
• peripheral arterial disease – in which a build-up of fatty deposits in the arteries restricts blood supply to leg muscles (people with diabetes, atherosclerosis and/or high cholesterol levels often go on to develop peripheral arterial disease)

Wet gangrene

Wet gangrene often occurs when a serious injury, a burn or frostbite becomes infected by bacteria.

The swelling caused by the infection can block the blood supply to the affected area which makes the infection worse.

Wet gangrene can spread much quicker than dry gangrene and can lead to further life-threatening symptoms, such as septic shock, if not treated promptly.

Other types

Other less common types of gangrene include:

• gas gangrene – where an infection develops deep inside the body and the bacteria responsible begin releasing toxins
• necrotising fasciitis – where bacteria spreads into the skin and then into surrounding tissue
• internal gangrene – when blood flow to an internal organ such as the gallbladder is blocked; this often occurs as a complication of a hernia

Read more about the potential causes of gangrene.

Complications

Having an amputation – even a so-called ‘minor amputation’ such as having one of your toes or fingers removed – can have a profound negative emotional impact.

Having an entire limb removed can cause serious psychological complications. People often grieve for the loss of their limb in the same way they would grieve for the loss of a loved one. Feelings of anger and depression are common.

Read more about the complications of gangrene and recovering from the effects of an amputation.

Prevention

Many cases of dry gangrene can be prevented.

Dry gangrene usually develops inside the foot of a person with poorly controlled diabetes, atherosclerosis and/or peripheral arterial disease.  If you have one of these conditions it’s important to have regular check-ups to assess the state of your feet and report any problems to your GP as soon as possible.  

A low-fat diet, regular exercise and, if you smoke, quitting smoking will also improve your blood supply.

Read more about preventing gangrene.

Who is affected

Dry gangrene is a relatively common problem among high-risk groups, such as people with diabetes and/or peripheral arterial disease, and is a common cause of amputations.

Diabetes UK estimates that people with diabetes are 15 times more likely to require a major amputation than the population at large.

Every year in England around 5,000 people with diabetes have an amputation as a result of gangrene.

There is limited data about other types of gangrene which are not thought common.

For example, from April 2010 to April 2011 there were 52 reported cases of gas gangrene and 903 cases of internal gangrene in England.