Cellulitis Health Article

Definition

Cellulitis is a common skin infection caused by bacteria.

See also:

• Orbital cellulitis
• Periorbital cellulitis

Alternative Names

Skin infection - bacterial

Causes, incidence, and risk factors

Staphylococcus and streptococcus bacteria are the most common causes of cellulitis.

The skin normally has many types of bacteria living on it. When there is a break in the skin, however, bacteria can enter the body and cause infection and inflammation. The skin tissues in the infected area become red, hot, irritated, and painful.

Risk factors for cellulitis include:

• Cracks or peeling skin between the toes
• History of peripheral vascular disease
• Injury or trauma with a break in the skin (skin wounds)
• Insect bites and stings, animal bites, or human bites
• Ulcers from diabetes or a blockage in the blood supply (ischemia)
• Use of corticosteroid medications or medications that suppress the immune system
• Wound from a recent surgery

Symptoms

• Fever
• Signs of infection:
  • Chills, shaking
  • Fatigue
  • General ill feeling (malaise)
  • Muscle aches, pains (myalgias)
  • Warm skin, sweating
• Pain or tenderness in the area with the rash or sore
• Skin redness or inflammation that increases in size as the infection spreads
• Skin sore or rash (macule):
  • Comes on suddenly
  • Grows quickly in the first 24 hours
  • Usually has sharp borders
• Tight, glossy, "stretched" appearance of the skin
• Warmth over the area of redness

Other symptoms that can occur with this disease:

• Hair loss at the site of infection
• Joint stiffness caused by swelling of the tissue over the joint
• Nausea and vomiting

Signs and tests

During a physical examination, the doctor may find:

• Redness, warmth, and swelling of the skin
• Swelling and drainage if the infection is around a skin wound
• Swollen glands (lymph nodes) near the cellulitis

Your health care provider may mark the edges of the redness with a pen, to see if the redness goes past the marked border over the next several days.

Tests that may be used:

• Blood culture
• Complete blood count (CBC)