Cellulitis (pronounced: sel-yuh-LY-tus) is a skin infection that involves areas of tissue below the surface of the skin.
Cellulitis can affect any area of the body, but is most common on exposed body parts, such as the face, arms, or lower legs.
What Causes Cellulitis?
Many different types of can cause cellulitis. The most common ones are group A streptococcus and Staphylococcus aureus.
Cellulitis usually begins in an area of broken skin, like a cut, bite, or scratch. People who have body piercings may be at risk for cellulitis because the piercing hole is a chance for bacteria to get beneath the skin's surface.
But cellulitis can also start in areas where the skin isn't broken, especially in people who have chronic conditions (such as diabetes) or who take medicines that affect the immune system.
Cellulitis is not contagious. It can't spread from person to person.
What Are the Signs & Symptoms of Cellulitis?
Cellulitis begins with a small area of skin that's:
As this area begins to spread, a person may begin to feel ill and get a fever and, sometimes, chills and sweats. Swollen lymph nodes (or swollen glands) are sometimes found near the area of infected skin.
The time it takes for symptoms to start varies, depending on which bacteria cause the cellulitis. For example, someone with cellulitis caused by Pasteurella multocida, commonly found in animal bites, can have symptoms less than 24 hours after the bite. But cellulitis caused by other types of bacteria may not cause symptoms for several days.
How Is Cellulitis Diagnosed?
A doctor can usually diagnose cellulitis by examining the area of affected skin. Sometimes the doctor may check for bacteria by taking blood samples. Positive blood cultures mean that bacteria from the skin infection have spread into the bloodstream. This can cause septicemia (blood poisoning), a serious infection.
How Is Cellulitis Treated?
If you have a mild case of cellulitis, the doctor will probably prescribe antibiotics. These can usually cure cellulitis in 7 to 10 days. Even if you feel better sooner than that, it's important to take all the prescribed for you. Otherwise, the infection can return.
People with severe cases of cellulitis might need treatment in a hospital with intravenous (IV) antibiotics.
Can Cellulitis Be Prevented?
To prevent cellulitis, protect skin from cuts, bruises, and scrapes. This isn't easy, especially if someone is active or likes to play sports.
Wear long pants and long-sleeved shirts while hiking in the woods (this can also protect you from bug bites and stings).
Wear sandals on the beach.
If you do get a scrape, wash the wound well with soap and water. Apply an antibiotic ointment and cover the wound with an adhesive bandage or gauze. Check wounds often for the first few days to see if any signs of cellulitis begin. Pay attention to new piercings too. If they get red, swollen, and painful to the touch, have them checked out by a doctor.
When Should I Call My Doctor?
Call your doctor whenever any area of your skin becomes red, warm, and painful — with or without fever and chills. This is especially important if the area of skin is on the hands, feet, or face (particularly ear, nose, or eyebrow piercings) or if you have an illness or condition that suppresses the immune system.
Check with your doctor if you get a large cut or a deep puncture wound. Cellulitis can happen quickly after an animal bite. So call your doctor if an animal bites you, especially if the puncture wound is deep. Not too many people get bitten by other people, of course, but human bites can cause skin infections too.
What Can I Do to Feel Better?
Take the antibiotics prescribed by the doctor exactly as directed and for the full course. Follow your doctor's suggestions for treating the area of cellulitis, such as elevating the affected part of your body or applying heat or warm soaks to it. You can also take over-the-counter pain relievers such as acetaminophen or ibuprofen to ease pain and keep a fever down.
After you've taken antibiotics for 1 or 2 days, your doctor may schedule an office visit to check that the area of cellulitis has improved. This means that the antibiotics are working against the infection.