Cellulitis is a common bacterial skin and subcutaneous infection that is most commonly caused by either Staphylococcus or Streptococcus bacteria. Both of these bacteria occur naturally on the skin. A break or cut in the skin causes the bacteria to enter the body, which leads to an active infection. Common predisposing factors include minor abrasions or lacerations, surgical wounds, insect bites, burns, intravenous catheters and other breaks in the skin barrier.

Cellulitis appears as a swollen pink to red area of skin that is tender and warm to the touch. It radiates from the initial site of infection outward. The redness is less intense than erysipelas because the infection is deeper. Symptoms may include chills, fever, muscle ache, fatigue, pain or tenderness in an area. The redness increases in size as the infection spreads. It may develop suddenly and spread quickly. Cellulitis can arise anywhere on the body, but it is more common on the arms and legs. To help prevent cellulitis, be sure to maintain clean, moisturized skin and address small scratches and wounds. Treating fungal infections of the feet may reduce the likelihood that cellulitis will develop.