Cellulitis is an infection of the skin and deep underlying tissues. Group A strep (streptococcal) bacteria are the most common cause. The bacteria enter your body when you get an injury such as a bruise, burn, surgical cut or wound.

Symptoms include: 

• Fever and chills 
• Swollen glands or lymph nodes 
• A rash with painful, red, tender skin — the skin may blister and scab over

An Ohio State dermatologist may take a sample or culture from your skin or do a blood test to identify the bacteria causing infection. Treatment is with antibiotics. They may be oral in mild cases or intravenous (through the vein) for more severe cases.

Source: National Institutes of Health: National Institute of Allergy and Infectious Diseases