What is necrotizing fasciitis?

Necrotizing fasciitis is an infection caused by bacteria. It can destroy skin, fat, and the tissue covering the muscles.

The disease sometimes is called "flesh-eating" bacteria. When it occurs on the genitals, it is called Fournier gangrene.

Necrotizing fasciitis is very rare but serious. About 3 out of 10 people who get this infection die from it.¹ Many people who get necrotizing fasciitis are in good health before they get the infection.²

Your risk of getting this infection is higher if you:

• Have a weak immune system.
• Have chronic health problems such as diabetes, cancer, or liver or kidney disease.
• Have cuts in your skin, including surgical wounds.
• Recently had chickenpox or other viral infections that cause a rash.
• Use steroid medicines, which can lower the body's resistance to infection.

What causes necrotizing fasciitis?

Necrotizing fasciitis is caused by several kinds of bacteria. Some of these bacteria also cause infections such as strep throat and impetigo. Usually the infections caused by these bacteria are mild. But in rare cases they can cause a more dangerous infection.

You can get necrotizing fasciitis in:

• Wounds that come in contact with ocean water, raw saltwater fish, or raw oysters. You also can get it though injuries from handling sea animals such as crabs.
• Intestinal surgery, or tumors or gunshot injuries in the intestines.
• A muscle strain or bruise, even if there is no break in the skin.

Bacteria that cause necrotizing fasciitis can be passed from person to person through close contact, such as kissing, or by touching the wound of the infected person. But a person who gets infected by the bacteria is unlikely to get necrotizing fasciitis unless he or she has an open wound, chickenpox, or an impaired immune system.

What are the symptoms?

The symptoms often start suddenly. You may have:

• Pain from an injury that gets better over 24 to 36 hours and then suddenly gets worse. The pain may be much worse than you would expect from the size of the wound or injury.
• Skin that is red, swollen, and hot to the touch.
• A fever and chills.
• Nausea and vomiting.
• Diarrhea.

The infection may spread rapidly. It quickly can become life-threatening. You may go into shock and have tissue damage. Necrotizing fasciitis can lead to organ failure and death.

How is necrotizing fasciitis diagnosed?

The doctor will diagnose your infection based on how suddenly your symptoms started and how quickly the infection is spreading. The infected tissue may be tested for bacteria. You also may need X-rays, a CT scan, or an MRI to look for injury to your organs or to find out how much the infection has spread.

How is it treated?