Cellulitis is usually caused by a bacterial infection. It occurs when bacteria get into the tissues beneath the skin.

Howthe infectionoccurs

The bacteria that cause cellulitis often live harmlessly on the skin. But if the surface of your skin is damaged, they can get into the layers underneath and cause an infection.

The break in the skin may be so small it's not noticeable.

Itmay be caused by:

  • a Lacerations
  • a burn
  • an animal or human bite
  • an insect bite
  • a puncture wound
  • a legulcer
  • the skin becoming dry and cracked for example, because of eczema or athlete's foot

Cellulitis isn't normally spread from person to person as the infection occurs deep within the skin and is often caused by bacteria that live on the skin's surface without causing problems.

Increased risk

Anyone can get cellulitis, but you're at an increased risk if:

  • you're obese you can use the healthy weight calculator to check your weight
  • you have poor circulation in your arms, legs, hands or feet
  • you have a weakened immune system for example, because of HIV or chemotherapy treatment
  • you have lymphoedema a condition that causes fluid to build up under your skin
  • you have poorlycontrolled diabetes
  • you've had cellulitis before
  • you use injected drugs

Ensuringthe underlying health conditionsmentioned above are well controlled may help reduce your risk of getting cellulitis.

Chronic usually means a condition that continues for a long time or keeps coming back.
Immune system
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.
The liver is the largest organ in the body. Its main jobs are to secrete bile (to help digestion), detoxify the blood and change food into energy.
Obesity is whena person has an abnormally high amount of body fat.
Veins are blood vessels that carry blood from the rest of the body back to the heart.
Content supplied by the NHS Website

Medically Reviewed by a doctor on 11 Aug 2016