Cellulitis is a deep bacterial infection of the skin. It can occur in any part of the body, but according to the Children's Hospital of Boston, it usually involves the face, arms, legs or any site that has sustained trauma. Trauma allows bacteria to circumvent the normal skin barrier against infection and proliferate, causing cellulitis. Complications of cellulitis include abscess formation, necrotizing fasciitis and osteomyelitis or bone infection.
Abscess
An abscess is a collection of pus surrounded by inflamed tissue. In essence, an abscess is the body's way of trying to contain an infection within a localized site, such as the site of skin trauma. White blood cells move into the affected site to fight and wall off the ensuing cellulitis, forming an abscess. Pus, which according to MedlinePlus is a fluid composed of dead white blood cells and bacteria, builds up within the abscess. This results in a swollen, painful, red area of skin. Treatment for an abscess involves antibiotics and surgical drainage, although in the more superficial abscesses, the pressure of fluid buildup will make it drain spontaneously. Warm compresses also help speed up this process.
Necrotizing Fasciitis
Necrotizing fasciitis, also known as the "flesh-eating bacteria," is another complication of cellulitis. Initially bacteria penetrate the skin after a traumatic event, which can be something as minor as a paper cut. Then cellulitis ensues. If the infection is not detected and treated in time, the bacteria continue infecting the deeper tissues of the skin, causing tissue destruction and inflammation. Fasciitis occurs when the infection spreads to the fascia, the sheath of tissue surrounding the muscles. According to the National Necrotizing Fasciitis Foundation, the most common bacterium that causes necrotizing fasciitis is group A strep, a common source of infection in children. The bacteria causes tissue destruction, toxic shock from the release of a toxin that causes organ failure, and can lead to amputation of an affected limb. Treatment includes intravenous antibiotics and surgery to remove dead tissue and prevent further spread of the bacteria.
Osteomyelitis
Osteomyelitis is a bacterial infection of a bone. There are several ways for bacteria to reach the bone and infect it, and one of those ways is by bacteria causing cellulitis and spreading to an adjacent bone. In children, this commonly happens on the long bones of the legs and the arms, which also are common sites for trauma and skin infections. Symptoms of osteomyelitis include pain, redness and cellulitis of the overlying skin, and fever. X-rays and MRIs can help establish the diagnosis of osteomyelitis. A bone biopsy can help in cases where the diagnosis is in doubt. Treatment includes long-term intravenous antibiotics and occasional surgical debridement or cleaning of the bone.
