Gangrene is a dangerous and potentially deadly health problem

It happens when the blood flow to an area of tissue is cut off. This causes the tissue to break down and die. Gangrene often turns the affected skin a greenish-black color. The word gangrene is not related to the color green, but to the condition itself. It comes from Greek and Latin words for a gnawing sore or decayed tissue.

There are different types of gangrene

Dry gangrene occurs when the blood flow to tissue is cut off. The area becomes dry, shrinks, and turns black.

Wet gangrene occurs if bacteria invade this tissue. This makes the area swell, drain fluid, and smell bad.

Gas gangrene occurs if bacteria invade the deep muscle tissue. The skin may have bubbles and it may have a crackling sound. This is because gas bubbles have formed in the muscle tissue.

Fournier’s gangrene occurs if bacteria invade the genital organs, such as the scrotum, penis, or perineum. An infection in the genital area or urinary tract associated with trauma, operative procedures, or urinary tract disease, can cause this. The area becomes painful and red, with quick progression to gangrene and sloughing of the tissue.

Causes

Gangrene happens when a body part loses its blood supply. This may happen from injury, an infection, or other causes.

You have a higher risk for gangrene if you have:

A serious injury, such as a burn, infected dog bite, or combat wound.
Blood vessel disease (such as arteriosclerosis, also called hardening of the arteries, in your arms or legs).
A chronic disease that harms the circulatory system, such as diabetes, peripheral artery disease, or Raynaud disease. These diseases can lead to gangrene if they are severe and not under control.
Suppressed immune system (for example, from HIV/AIDS or chemotherapy).
Surgery.
An infection.
Severe cases of frostbite.
Certain medicines.

Symptoms of gangrene

Depend on its location and cause. Dry gangrene often starts with a red line around the affected area. This area then turns dry and black.

These are other symptoms of gangrene:

Coldness and numbness in the affected area.
Pain in or beyond the affected area.
Redness and swelling around a wound. This is often a sign of wet gangrene.
Sores that keep cropping up in the same place.
Persistent, unexplained fever, with a temperature higher than 100.4°F (38°C).
A bad-smelling wound.
Striking discoloration of the skin, with shades of greenish-black, blue, red, or bronze.
Pus or discharge from a wound.
Blisters and a crackling feeling under the skin.
Muscle aches, weakness, diarrhea, and loss of appetite (sometimes).
Confusion, pain, fever, and low blood pressure, especially if the infected gangrene spreads inside your body.
Shock.

The earlier gangrene is treated, the more successful the treatment is likely to be. So if you have any of the above symptoms, seek care right away.

Recognizing the signs of 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 that 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 that 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: