Cellulitis is a bacterial infection of the skin and soft tissues. It is usually caused by staphylococci (“staph”) or streptococci (“strep”) bacteria that commonly live on the skin or inner surface of the nose or mouth of healthy people. Cellulitis usually affects the deeper layers of the skin or the fat under the skin and is not usually contagious unless it is draining pus or fluid.
Cellulitis commonly affects the leg, though it may also involve the arm, around the eye, the breast, the abdominal wall or any area of the body that has an open wound.
Cellulitis of the leg and other parts of the body is usually mild and the affected skin can be treated with antibiotics. But some cases of cellulitis of the leg or other parts of the body can be severe and lead to systemic infection.
What Causes Cellulitis of the Leg?
Cellulitis is an infection usually caused by staphylococci ("Staph") or streptococci ("Strep") bacteria that live on the skin or inner surface of the nose or mouth of healthy people. Cellulitis may develop if there is a wound or other break in the skin, that can be minor and unnoticed. This break in the skin permits the bacteria to enter the skin, causing infection and swelling.
Risk factors for developing cellulitis include:
- Recent skin injury (wounds, abrasions, cuts, bites, tattoos, piercings, ulcers, or injection drug use)
- Prior radiation therapy to the area
- A fungal or viral skin infection, such as athlete's foot or chickenpox
- Fluid accumulation (edema) due to poor circulation, heart failure, liver disease, chronic lymphedema, or past surgery to remove lymph nodes
- Overweight/obesity
- Chronic skin conditions, such as eczema or athlete’s foot
- Chickenpox and shingles
How Is Cellulitis of the Leg Diagnosed?
Cellulitis of the leg is usually diagnosed with a physical examination of the affected skin.
Blood tests and other lab tests are usually not needed in mild cases, although bacterial cultures may be taken to figure out the germ that caused the infection to help determine treatment.
What Is the Treatment for Cellulitis of the Leg?
Treatment for cellulitis of the leg includes antibiotics and treatment of any underlying condition that led to the infection.
Home care for cellulitis of the leg includes:
- Elevate the leg above the heart to help reduce swelling and facilitate healing
- Keep the affected area clean and dry
- Only use antibiotic ointments or creams if prescribed by your doctor
- Rest and give the body time to heal
- Fever and chills, if they occurred, should go away within one to two days after starting antibiotic therapy
- Swelling, warmth, and redness should begin to improve within one to three days after starting antibiotics, though it may continue for up to two weeks
Medical treatment for cellulitis of the leg includes:
- Antibiotics
- The choice of antibiotic depends the bacterial cause of the cellulitis
- In severe cases, hospitalization may be needed and intravenous (IV) antibiotics may be given
What Are Complications of Cellulitis of the Leg?
Complications from cellulitis are uncommon and may include:
- Serious infections
- Blood (bacteremia)
- Joints (suppurative arthritis)
- Bone (osteomyelitis)
- Lining of the chambers of the heart and heart valves (endocarditis)
- Vein swelling if blood clots form close to the skin (thrombophlebitis)
- Necrotizing fasciitis (in severe cases)
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https://www.cdc.gov/groupastrep/diseases-public/Cellulitis.html