Gangrene is when part of your body tissue dies. This often occurs because the tissue is not getting enough blood from your circulatory system.

Gangrene usually affects your extremities — the areas farthest from your heart, such as your toes and fingers. However, it can affect other parts of your body as well. Gangrene can even affect your internal organs.

The condition typically starts in a specific body part, such as a leg, hand, or internal organ. Gangrene can spread through your body and cause you to go into shock if left untreated. Shock is a condition marked by a variety of symptoms including low blood pressure. Shock can be life-threatening and is considered a medical emergency.

Gangrene is a medical emergency that could lead to amputations or death. Recognizing and treating the condition as fast as possible will improve your outlook.

Dry gangrene

All of your organs (such as your liver, heart, and muscles) need oxygen to function properly and survive. The oxygen is carried to different parts of your body by your blood. Dry gangrene occurs when one of your body parts isn’t getting enough oxygen. Eventually, the body part will start to deteriorate and die. With dry gangrene, the skin is closed and there is no evidence of infection.

Wet gangrene

Wet gangrene happens when your body tissues become infected with some type of bacteria. The tissues react to the presence of the bacteria by growing moist and breaking down. This process causes the death of your tissues. It’s more of an emergency than dry gangrene because of the possibility of infection spreading to other parts of the body.

Gas gangrene

Bacteria called Clostridia cause gas gangrene. These bacteria create an infection that causes gas bubbles and toxins to develop inside the affected area. The resulting gases cause tissue death. This type of gangrene can be fatal, though it’s rare in the United States.

You are more likely to develop gangrene if you have a history of certain medical conditions, including:

Some other physical events could increase your risk of gangrene. You may be more likely to develop this condition if you:

  • have lowered immunity because of a medical condition or cancer treatment
  • have recently had surgery
  • have suffered severe frostbite or a head injury, animal bite, or serious burn
  • have been hurt in a traumatic way that includes the crushing of body tissues
  • have had an injection of promethazine hydrochloride that led to tissue damage

Smoking, drinking alcohol, and using intravenous drugs may also add to your risk of developing gangrene.

External gangrene

Sometimes the first sign of dry gangrene is a reddish line that develops around the affected tissue. This line may later turn black.

Other signs that might indicate you have gangrene include:

  • a wound that is red, sore, or swollen
  • a wound that is filled with pus or gives off a bad smell
  • an isolated area of your body feels cold
  • lacking a sense of touch in an isolated area
  • sores that keep coming back in the same place on your body
  • part of your skin has turned an unusual color (greenish-black, red, blue, or bronze)

Internal gangrene

It’s also possible to experience internal gangrene, which affects your inner tissues or organs. In this case, you may not have any symptoms on your skin or limbs. However, you may have pain, an unexplained fever that lasts a long time, or low blood pressure. You may also experience confusion.

Your doctor may suspect that you have gangrene based on your medical history and symptoms. They may also use a combination of additional diagnostic methods to determine your condition.

Lab analysis of tissue or fluid samples

A scraping of tissue from your affected body part may be examined with a microscope to look for dead cells.

Blood tests

An abnormally high white blood cell count can indicate a gangrenous infection.

Medical imaging

Some kinds of imaging are helpful in diagnosing the spread of gangrene in your internal tissues. These tests could include X-rays, MRI scans, or CT scans.

An anarteriogram test may be performed if doctors suspect that your gangrene is related to a circulatory problem. This test uses X-rays to monitor the flow of a special dye through your arteries, showing whether any arteries are blocked.

Antibiotics

Your doctor may prescribe antibiotics if bacteria are present. These are typically given intravenously, or through a needle directly into the bloodstream.

Vascular surgery

For people with poor circulation that results in gangrene, vascular surgery (surgery on the arteries or veins) may be recommended in order to improve the flow of blood through the veins to body tissues.

Hyperbaric oxygen chamber

Placing a person with gas gangrene in a special oxygen-rich environment can slow the growth of bacteria. This allows the skin to begin healing. It also brings oxygen to the damaged tissue to promote healing.

Tissue debridement

In serious gangrene cases, the dead tissue or body part may need to be removed. This process is called debridement. Debridement can be done with surgical tools or with chemicals. The goal of this type of surgery is to remove the affected areas to prevent the spread of infection and rid the body of the dead tissue.

One alternative form of debridement, known as maggot debridement, uses fly larvae to eat away bacteria and dead tissue. Though rare, this practice can still be used by physicians in the United States and abroad.

Doctors are sometimes able to restore the flow of oxygen to the affected area. Skin grafts can repair any damaged tissue. This procedure uses a piece of your healthy skin from elsewhere on the body to cover the damaged area.

Amputation

For severe cases, amputation of a limb, finger, or toe could be necessary to save your life. People who must have part of an arm or leg amputated due to gangrene may be fitted with a prosthesis, or artificial limb, to replace the missing body part.

Gangrene can sometimes be treated without serious complications, especially if it is caught early. However, it can lead to amputation in some serious cases, particularly if it’s not treated quickly.

Gangrene can even be fatal for some individuals. This is rare, but it can occur if:

  • you have other serious medical issues that complicate your treatment
  • the gangrenous area covers a large part of your body
  • treatment is not provided quickly enough

To keep more tissue from dying, gangrene must be treated early to minimize the damage. People who have diabetes or a blood vessel disease should regularly check their hands and feet for gangrene symptoms. Watch for:

  • any swelling, discharge, or redness that may indicate infection
  • a wound that does not seem to be healing
  • a change in the color of your skin

Taking antibiotics before or after having surgery, under the care of your doctor, may help you prevent the development of gangrenous infections.