Cause of Cellulitis
The most common cause of cellulitis in adults with no other medical conditions is group A streptococcus, which is a bacterium commonly found in the throat and on the skin. Certain risk factors --such as problems with the lymphatic system and breaks in the skin -- can increase a person's chances of developing cellulitis.
Cellulitis is an infection that is caused by bacteria. Although doctors are aware of its causes, they can seldom explain why one person will get the infection and another person will not.
The most common cellulitis cause in adults with no medical conditions is group A streptococcus, which is a bacterium commonly found in the throat and on the skin.
Another common cause in adults is Staphylococcus aureus (S. aureus), which is a bacterium that is commonly found on human skin and mucosa (lining of mouth and nose).
In rare cases, other bacteria can cause cellulitis. When this does occur, it is usually the result of a medical condition such as diabetes, HIV, or AIDS, or because the cellulitis is in a very specific place.
Other bacteria that can lead to cellulitis include:
- Methicillin-resistant S. aureus (MRSA)
- P. aeruginosa
- Vibrio vulnificus
- Clostridium septicum
- Pasteurella multocida
- E. coli
- Group B streptococcus.
Cellulitis research has shown that people with certain risk factors are more likely to develop the infection. Generally, cellulitis risk factors include:
- Problems with the lymphatic system
- Vein problems
- Swelling of the leg
- Breaks in the skin
Specific cellulitis risk factors include:
- Surgical wounds
- Skin ulcer (such as a diabetic foot ulcer)
- Athlete's foot
- Eczema, psoriasis, or other skin conditions that may cause a break in the skin
- A previous episode of cellulitis
- Surgery with lymph node removal
- Radiation therapy
- Coronary artery bypass surgery
- IV drug use
- Certain conditions (such as diabetes, HIV or AIDS, leukemia, lymphoma, psoriasis, dyshidrosis, lupus, and heart failure).
Risk factors for cellulitis are not causes of the condition; however, such risk factors do increase a person's chance of developing the infection. People who think that they may be at risk of developing cellulitis should discuss this concern with their doctor.