Necrotizing fasciitis is a rare infection that's often described in media reports as a condition involving "flesh-eating bacteria." It can be fatal if not treated promptly.
Necrotizing fasciitis spreads quickly and aggressively in an infected person. It causes tissue death at the infection site and beyond.
Every year, between 600 and 700 cases are diagnosed in the U.S. About 25% to 30% of those cases result in death. It rarely occurs in children.
How Do You Get Necrotizing Fasciitis?
The bacteria that cause necrotizing fasciitis can enter the body following surgery or injury. They can also enter the body through:
- minor cuts
- insect bites
In some cases, it is unknown how the infection began. Once it takes hold, the infection rapidly destroys muscle, skin, and fat tissue.
Causes of Necrotizing Fasciitis
Necrotizing fasciitis is commonly caused by group A Streptococcus (GAS) bacteria. That's the same type of bacteria that causes strep throat. However, several types of bacteria, such as staphylococcus and others, have also been associated with the disease.
Necrotizing fasciitis occurs when such bacteria infect the superficial fascia, a layer of connective tissue below the skin.
Symptoms of Necrotizing Fasciitis
The symptoms of necrotizing fasciitis usually occur within the first 24 hours of infection. They often include a combination of the following:
- Increasing pain in the general area of a minor cut, abrasion, or other skin opening.
- Pain that is worse than would be expected from the appearance of the cut or abrasion.
- Redness and warmth around the wound, though symptoms can begin at other areas of the body.
- Flu-like symptoms such as diarrhea, nausea, fever, dizziness, weakness, and general malaise.
- Intense thirst due to dehydration.
More advanced symptoms occur around the painful infection site within three to four days of infection. They include:
- Swelling, possibly accompanied by a purplish rash.
- Large, violet-colored marks that transform into blisters filled with dark, foul-smelling fluid.
- Discoloration, peeling, and flakiness as tissue death (gangrene) occurs.
Critical symptoms, which often occur within four to five days of infection, include:
- severe drop in blood pressure
- toxic shock