Bacterial infection of the skin and underlying tissues that causes redness and swelling

  • More common in elderly people
  • Intravenous drug use is a risk factor
  • Gender and genetics are not significant factors

In cellulitis, an area of skin and the underlying tissues become infected by bacteria that enter through a small, possibly unnoticed, wound. The infection causes redness, pain, and swelling and most commonly affects the legs.

Elderly people are especially vulnerable to cellulitis because they are more likely to have poor circulation, which leads to oedema (fluid build-up in the tissues) or leg ulcers. These problems increase the risk of infection. Others who are at increased risk of cellulitis include intravenous drug users and people whose resistance to infection has been lowered by disorders such as diabetes mellitus or AIDS (see HIV infection and AIDS).

What are the symptoms?

The symptoms appear gradually over several hours and include:

  • Redness, swelling, and in some cases warmth in the affected area of skin.

  • Pain and tenderness in the area.

  • Occasionally, fever and chills.

If you develop these symptoms, consult your doctor without delay. Left untreated, cellulitis may cause septicaemia, a serious blood infection.

What might be done?

If you have an obvious wound, your doctor may take a swab from the area to identify the bacterium that is causing the infection. The doctor will probably prescribe oral antibiotics, which should take effect within 48 hours. In severe cases, you may need hospital treatment with intravenous antibiotics. If your leg is affected, you should keep it elevated to help to reduce the swelling. Cellulitis may recur if you have a persistent immune or circulatory problem, and long-term antibiotics may be needed in such cases.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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