What Is Cellulitis?
Cellulitis is a bacterial skin infection characterized by pain, redness and swelling of the affected area. It’s common and easy to treat with antibiotics but can spread quickly to the bloodstream and lymph nodes, causing serious, potentially life-threatening complications. If you suspect you have cellulitis, seek medical care right away.
Cellulitis occurs when bacteria enter an opening in the skin, such as a cut, crack, bite or scrape. The two types of bacteria most often associated with cellulitis are streptococcus (strep) and staphylococcus (staph).
An increasing number of cases are caused by a type of staph called methicillin-resistant staphylococcus aureus (MRSA). Cellulitis caused by MRSA is especially concerning because it doesn’t respond to many of the antibiotics usually prescribed to treat staph infections.
Cellulitis Risk Factors
Anyone can develop cellulitis, but certain conditions and medications increase your vulnerability, including:
• Diabetes, HIV and other diseases that weaken the immune system
• Skin conditions such as eczema, athlete’s foot and psoriasis that cause breaks in the skin
• Lymphedema (a chronic swelling of the arms and legs)
• Being overweight or obese
• Liver diseases such as hepatitis and cirrhosis
• Varicose veins
• A past history of cellulitis
• Use of immunosuppressive drugs, such as those prescribed for autoimmune diseases including lupus and rheumatoid arthritis
The affected area may be red, swollen, warm, tender and painful. Red spots and blisters can develop, and your skin may look pitted and resemble an orange peel. You may also have a fever.
In some cases, cellulitis requires emergency care. Seek help immediately if you experience any of these symptoms, which may indicate the infection is spreading:
• Increasing pain
• High fever or chills
• Nausea and vomiting
• Numbness in the affected area when touched
• Enlargement or hardening of the affected area
When cellulitis spreads, serious complications can result, including septicemia (a bloodstream infection that can be fatal), lymphedema and gangrene, a medical emergency.
In rare cases, cellulitis can infect a layer of connective tissue beneath the skin called fascia, causing necrotizing fasciitis, sometimes called "flesh-eating disease.” This type of infection spreads rapidly and can be fatal, so immediate treatment is critical.
Early symptoms of necrotizing fasciitis include severe pain, fever and a red, warm or swollen patch of skin that enlarges quickly. Later symptoms include ulcers, blisters or black spots on the skin, changing skin color, pus or oozing from the affected area, dizziness, fatigue and diarrhea or nausea.
Treating cellulitis typically involves prescribing an antibiotic to kill the infection. Antibiotics work quickly, often within a day or two, but are typically are prescribed for five, 10 or even 14 days to thoroughly kill the bacteria. Take the entire course of antibiotic prescribed even after you start feeling better, and let your doctor know if you don’t respond to treatment within three days.
Measures that can ease discomfort and swelling include taking over-the-counter pain medication, elevating the affected area and applying a cool, damp cloth. Compression wraps or stockings may also be helpful.
In some cases, people with cellulitis need to be treated in a hospital with intravenous antibiotics. Your doctor may recommend this if your symptoms are extensive or aren’t responding to oral antibiotics or you have a high fever.