Gangrene is a condition that occurs when body tissue dies. It is caused by a loss of blood supply due to an underlying illness, injury, and/or infection. Fingers, toes, and limbs are most often affected, but gangrene can also occur inside the body, damaging organs and muscles. There are different types of gangrene and all require immediate medical attention.
Blood plays a very important role in your health. Not only does it transport oxygen and nutrients throughout your body to feed cells, it delivers disease-fighting antibodies that protect your body from infection. When blood cannot travel freely throughout the body, your cells cannot survive, infection can develop, and tissue can die from gangrene. Any condition that affects blood flow increases your risk of gangrene, including:
- Peripheral arterial disease
- Trauma or serious injury
- Raynaud's phenomenon (a condition in which the blood vessels that supply the skin become intermittently narrowed)
- Weakened immune system
There are two main types of gangrene:
Dry gangrene: More common in people with blood vessel disease, diabetes, and autoimmune diseases, dry gangrene usually affects the hands and feet. It develops when blood flow to the affected area is impaired, usually as a result of poor circulation. In this type, the tissue dries up and may be brown to purplish-blue to black in color and often falls off. Unlike other types of gangrene, infection is typically not present in dry gangrene. However, dry gangrene can lead to wet gangrene if it becomes infected.
Wet gangrene: Unlike dry gangrene, wet gangrene almost always involves an infection. Injury from burns or trauma where a body part is crushed or squeezed can rapidly cut off blood supply to the affected area, causing tissue death and increased risk of infection. The tissue swells and blisters and is called "wet" because of pus. Infection from wet gangrene can spread quickly throughout the body, making wet gangrene a very serious and potentially life-threatening condition if not treated quickly.
Types of wet gangrene include:
Internal gangrene: If gangrene occurs inside the body due to blocked blood flow to an internal organ, then it is referred to as internal gangrene. This is usually related to an infected organ such as the appendix or colon.
Gas gangrene: Gas gangrene is rare but dangerous. It occurs when infection develops deep inside the body, such as inside muscles or organs, usually as a result of trauma. The bacteria that causes gas gangrene, called clostridia, release dangerous toxins or poisons that wreak havoc throughout the body, along with gas which can be trapped within body tissue. As the condition progresses, the skin may become pale and gray, and make a crackling sound when pressed, due to the gas within the tissue. Gas gangrene warrants immediate medical treatment. Without treatment, death can occur within 48 hours.
Fournier's gangrene: Also a rare condition, Fournier's gangrene is caused by an infection in the genital area. Men are affected more often than women. If the infection gets into the bloodstream, a condition called sepsis, it can be life-threatening.
You may notice the following symptoms at the site of the dry gangrene:
- Dry and shriveled skin that changes color from blue to black and eventually sloughs off
- Cold and numb skin
- Pain may or may not be present
Symptoms of wet gangrene may include:
- Swelling and pain at the site of infection
- Change in skin color from red to brown to black
- Blisters or sores that produce a bad-smelling discharge (pus)
- Fever and feeling unwell
- A crackling noise that comes from the affected area when pressed
Internal gangrene usually is painful in the area of the gangrene. For example, a person with gangrene of the appendix or colon would be expected to have severe abdominal pain in the vicinity of the gangrene.
If infection from gangrene gets into the blood, you may develop sepsis and go into septic shock. This can be life-threatening if not treated immediately. Symptoms of sepsis may include:
- Low blood pressure
- Rapid heartbeat
- Shortness of breath
- Change in body temperature
- Body pain and rash
- Cold, clammy, and pale skin
If you think you or a loved one may have sepsis, go to the emergency room immediately.
Treatment for gangrene involves removing the dead tissue, treating and preventing the spread of infection, and treating the condition that caused gangrene to develop. The sooner you receive treatment, the better your chance of recovery. Depending on the type of gangrene, treatment may include:
Surgery. Also called debridement, the dead tissue is surgically removed to prevent the spread of infection. In some situations, amputation (removal of the affected limb, finger or toe) may be required.
Maggot therapy. Believe it or not, maggots still play a role in modern medicine. Maggots provide a non-surgical way to remove dead tissue. When used to treat gangrene, maggots from fly larvae (specially bred in a laboratory so they are sterile) are placed on the wound, where they consume the dead and infected tissue without harming healthy tissue. They also help fight infection and speed up healing by releasing substances that kill bacteria.
Oxygen therapy. Hyperbaric oxygen therapy may be used in some cases of wet gangrene or ulcers related to diabetes or peripheral artery disease. During treatment, the patient is put in a specially designed chamber filled with oxygen at a higher pressure than oxygen found in the outside air. The theory is that this high level of oxygen saturates the blood and encourages healing of the dying tissue. Oxygen therapy may also reduce the growth of bacteria that cannot thrive in an oxygen-rich environment.
In order to prevent gangrene from occurring again, the cause of any blood supply blockage must be determined so that the underlying condition can be treated. Often vascular surgery, such as bypass surgery or angioplasty, is needed to restore blood flow. Medication to prevent blood clots may be used in some cases.
Gangrene is a serious medical condition that requires immediate medical treatment. While most people with dry gangrene recover fully with treatment, gangrene that involves an infection can be life-threatening. The sooner you get treatment, the better your chances of recovery. If you have ongoing and unexplained pain in any area in your body, fever, a wound that is slow to heal, or you notice a change in skin color, make an appointment to see your doctor right away or go to the emergency room.