What is Necrotizing Fasciitis?

Necrotizing fasciitis is a rare infection that attacks muscle, fat and skin tissue (fascia) and causes it to die. More commonly known as flesh-eating bacteria, the infection is caused when bacteria enters the skin through a superficial injury or minor break in the skin and begins attacking healthy tissue. It is a fast-moving infection and requires quick diagnosis for effective treatment. If not treated early and aggressively, it can be fatal. In fact, the average duration from symptom onset to death can be less than 36 hours.

The reason necrotizing fasciitis moves so fast through the body is because the bacteria starts producing toxins immediately after entering the skin's surface. These toxins cut off blood flow to the surrounding muscle, fat and skin tissues causing them to die. As the toxins spread, they quickly eat away at the tissue and multiply. I've actually watched it move up a patient's leg while I was sitting at their bedside, that's how fast it can travel, says Dr. Linda Yancey, an Infectious Disease Specialist affiliated with Memorial Hermann.

What Causes Necrotizing Fasciitis?

There are different types of bacteria that cause necrotizing fasciitis, however, the most common is Streptococcus A, the same bacteria that causes strep throat. The strep bacteria can cause a broad range of illnesses and infections, most of which are not life-threatening. However, The Centers for Disease Control have categorized necrotizing fasciitis as an invasive group A strep disease because the infection attacks the body's connective tissue, which is not usually a target of bacterial infections.

Symptoms

The first symptom to occur with necrotizing fasciitis is pain. While the surface of the skin may appear normal, the severity of the pain experienced is usually out of proportion to the physical exam.If the affected limb is moved at all, the patient will experience severe pain, explains Dr. Yancey. Fever, chills and confusion are also very common symptoms with this infection. Diagnosis is difficult in the early stages since emergency room staff see similar complaints of fever, confusion, and pain with patients suffering from other medical issues. The distinguishing factor for physicians and other medical staff is when the infection is accompanied by sepsis, which is a whole-body reaction to the infection. Sepsis can present rapid, shallow breathing, increased heart rate and fever, and is considered a medical emergency.

Treatment

Once the diagnosis of necrotizing fasciitis is confirmed, emergency surgery will be necessary in order to stop the spread of the infection. Intravenous antibiotics will also be administered to help the body better fight the infection. With surgery, the main goal is to drain the source of the infection and remove the dead tissue. The removal of tissue creates very large wounds and, in some cases, requires amputation of the affected limb.

As a result of these large wounds, recovery takes an extended amount of time and may last for several months. Patients in recovery from necrotizing fasciitis will be in an intensive care unit to help with wound care after surgery. Additional treatments including hyperbaric oxygen therapy may be utilized to promote tissue recovery while inhibiting bacterial growth during the healing process.

Prevention

"Basically, if you have skin you are at risk for necrotizing fasciitis, says Dr. Yancey. While necrotizing fasciitis is quite rare, it is a serious health concern. According to the Centers for Disease Control, 650 to 850 cases are reported each year in the U.S., with an average mortality rate of 25%. To put those numbers into perspective, about 200 people in the U.S. die from bee stings each year. Your best defense is awareness and staying in good health overall. To reduce your risk for contracting necrotizing fasciitis, maintain a healthy lifestyle and practice good hygiene and proper wound care.