<p>Cellulitis is an infection of the skin and deep underlying tissues. Group A strep (<a href="https://medlineplus.gov/streptococcalinfections.html">streptococcal</a>) 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.</p> <p>Symptoms include:</p><ul> <li>Fever and chills</li> <li>Swollen glands or lymph nodes</li> <li>A rash with painful, red, tender skin. The skin may blister and scab over.</li> </ul> <p>Your health care provider 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 (by IV) for more severe cases.</p>