Cellulitis is a common infection of the skin and the soft tissues underneath. It happens when bacteria enter a break in the skin and spread. The result is infection, which may cause swelling, redness, pain, or warmth.
You’re at risk if you have:
- Trauma to the skin
- Circulatory problems, such as not enough blood flow to your arms and legs, poor drainage of your veins or lymphatic system, or varicose veins twisted, enlarged veins near the surface of the skin
- Liver disease such as chronic hepatitis or cirrhosis
- Skin disorders such as eczema, psoriasis, or infectious diseases that cause sores, such as chickenpox
Cellulitis is a localized or diffuse inflammation of connective tissue with severe inflammation of dermal and subcutaneous layers of the skin. A skin infection caused by bacteria, usually caused by the group A streptococcus bacteria.
What is cellulitis?
Cellulitis is a bacterial infection of the skin and tissues beneath the skin. Unlike impetigo, which is a very superficial skin infection, cellulitis is an infection that also involves the skin’s deeper layers: the dermis and subcutaneous tissue. The main bacteria responsible for cellulitis are Streptococcus and Staphylococcus (“staph”), the same bacteria that can cause impetigo. MRSA (methicillin-resistant Staph aureus) can also cause cellulitis. Sometimes, other bacteria (for example, Hemophilus influenzae, Pneumococcus, and Clostridium species) may cause cellulitis as well.
- Cellulitis is a spreading bacterial infection of the skin and tissues beneath the skin.
- Staphylococcus and Streptococcus are the types of bacteria that are usually responsible for cellulitis, although many types of bacteria can cause the condition.
- Sometimes cellulitis appears in areas where the skin has broken open, such as the skin near ulcers or surgical wounds.
- Cellulitis is not contagious.
- Cellulitis is treated with oral or intravenous antibiotics.
What are cellulitis symptoms and signs?
Cellulitis usually begins as a small area of tenderness, swelling, and redness that spreads to adjacent skin. As this red area begins to enlarge, the affected person may develop a fever, sometimes with chills and sweats, tenderness, and swollen lymph nodes (“swollen glands”) near the area of infected skin.
Causes of cellulitis
Cellulitis is usually caused by an infection of the tissues beneath the skin after the surface of the skin is damaged.
The type of infection is usually either:
- a group A streptococcal infection
- a staphyloccocal infection
If the surface of your skin is damaged, this creates an entry point for bacteria, allowing them to attack the skin and tissue underneath. The break may be so small it’s not noticeable.
A break in the skin may be caused by a:
- cut or graze
- animal, human or insect bite
- puncture wound
- venous leg ulcer
- skin condition, such as atopic eczema (this causes the skin to become dry, red and cracked) or athlete’s foot
Some cases of cellulitis can develop if a wound or other break in the skin is exposed to water that is contaminated with bacteria.
A fungal infection is a much rarer cause of cellulitis. Fungal cellulitis usually only affects people with a severely weakened immune system, such as a person in the final stages of an HIV infection that is not responding to treatment.
Cellulitis usually goes away after taking antibiotics for 7 to 10 days. Longer treatment may be needed if cellulitis is more severe. This may occur if you have a chronic diseases or your immune system is not working properly.
People with fungal infections of the feet may have cellulitis that keeps coming back. Cracks in the skin from the fungal infection allows the bacteria to get into the skin.
Treatment for Cellulitis
- Rest the area.
- Elevate the area to help reduce swelling and relieve discomfort.
- Use over-the-counter pain relievers such as acetaminophen (Tylenol) or ibuprofen (Motrin) to ease the pain, as well as keep your fever down.
If the infection isn’t too bad, you can take antibiotics by mouth for a week to 14 days. Your doctor will schedule a follow-up appointment. Your doctor may use IV or intramuscular antibiotics if:
- The infection is severe.
- You have other medical problems.
- You are very young or very old.
- The cellulitis covers large areas, is on your hands, or is close to body parts like your eyes.
- The infection worsens even after taking antibiotics for 2 to 3 days.
In serious cases, you may need to stay in the hospital. You’ll get IV antibiotics until the infection is under control (2 to 3 days), and then go home with oral medicines.