Cellulitis is a bacterial infection of the skin and of the soft tissue underlying the skin. The infection is usually caused by staphylococci ("Staph") or streptococci ("Strep") that are common on the skin of healthy individuals. They are also found inside the nose or mouth of careers and can be a source of recurrent infections including cellulitis. When there is break in the skin from trauma or another infection, viral or fungal, bacteria can enter skin and cause redness and swelling typically seen in cellulitis. 

Most cases of cellulitis are self-limited and mild in severity. Oral antibiotics can clear the infected skin completely. However, some cases are severe and cause generalized infections. It is important to seek medical care immediately for worsening symptoms, fevers, rapid growth of redness and swelling around infected swelling, pain or loss of sensation of skin. Certain individuals including diabetics are at increased risk of complications and must seek care promptly.

What are the risk factors for cellulitis?

Conditions that increase the risk of developing cellulitis:

●Injury to the skin from a wound, cut, shaving, injection, abrasion, or drug abuse

●Prior radiation treatment to the area

●Co-existing fungal or viral skin infection, such as athlete's foot, molluscum or chickenpox

●Swelling or accumulation of fluid due to poor circulation (edema), heart failure, liver disease, or past surgery to remove lymph nodes causing lymphedema.

●Obese or overweight

●Poorly controlled skin conditions like eczema


However, cellulitis can also develop without any known risk factors.

What are the symptoms of cellulitis?

Development of cellulitis can be gradual or sudden. The most common symptoms are redness, warmth, swelling and pain or tenderness over a defined area. The usual sites of involvement are shins, arms, around the eye, the breast and abdominal wall. The redness may expand over a matter of hours or days, indicating rapid progression of infection. Itching is not a typical symptom and can be used to distinguish cellulitis from other non-infectious causes of localized redness and swelling. The skin overlying cellulitis is usually smooth and shiny, while skin in stasis dermatitis, which can be confused with cellulitis, is raised or bumpy. However, with intense inflammation in cellulitis, small blisters or bumps may appear. 

Treatment of Cellulitis

Antibiotics —Treatment for cellulitis is started with oral antibiotics that are believed to be active against the bacteria that cause cellulitis. Usual duration of treatment is for 5-14 days.  Sometimes changes to antibiotic regimen are needed if there is no improvement, or worsening of symptoms. Delays in seeking medical care or use of wrong treatment can worsen the infection. It is important to take the antibiotic with prescribed instructions and entire duration. Incomplete treatment with skipped doses or shorter duration can cause bacterial resistance and/or longer treatment courses, in addition to worsening infection. Sometimes, cellulitis can worsen despite appropriate oral antibiotics, and may require intravenous antibiotics during hospitalization.

Elevation — Arms and legs elevated with extra pillows to above the level of the heart can help reduce swelling and speed up healing.

Skin Care — It is important to keep the infected area clean and dry. It is important to use gentle cleansers and shower and cleanse regularly especially for wounds with a lot of seepage. Avoid using loofa or other mechanical tools for cleansing as they can cause more skin injury. Dry gently using a patting motion with your towel. You can use a gauze to catch any drainage or bandage to protect the skin if needed. Improvement in swelling, redness, warmth, and in fevers and chills, if present, should occur within one to three days after starting antibiotic therapy, although skin symptoms can last for up to two weeks. Cellulitis is not highly contagious to other family members, but it is important to wash hands regularly and to avoid sharing towels.

Depending on your signs and symptoms your dermatologist can help determine the right treatment option for you.