Cellulitis is a skin infection caused by bacteria. Most often, the bacteria responsible for the skin infection are staphylococcus and streptococcus species, according to MedlinePlus, which is an online medical encyclopedia. Bacteria are everywhere in the natural world, and the skin is the first defense that bars entry of bacteria into the body. When the skin is cut or wounded, infection may occur, including cellulitis. There are a few different types of cellulitis, which differ based upon the site of the body that is affected.
Cellulitis of the Extremities
The most common sites of cellulitis, according to the Mayo Clinic, are the lower legs. Being afflicted with other skin disorders potentially creates an environment for cellulitis of the extremities to occur. For example, athlete's foot is a type of fungal foot infection that thrives in the dark moist environment inside a sock. The damage to the skin caused by athlete's foot can cause breakage in the skin, and bacterial species that normally live on top of the skin may now be able to get inside the skin and cause a skin infection. Extremities are also common sites of cellulitis because cracks in dry and flaky skin can serve as entry points for the bacteria, which are common on the hands and feet. The signs and symptoms of cellulitis of the extremities involve inflammation of the skin. Specifically, the infected area of the skin can become red, swollen, warm or painful. The infection may also be associated with a fever. Spreading of the red area of the skin is an indication that the infection is spreading, and red spots may appear on top of the red skin.
Orbital Cellulitis
Orbital cellulitis is a bacterial infection of the skin immediately lining the eye socket, according to the online medical library Merck Manuals. The infection that results in orbital cellulitis often spreads from an infected sinus, which is the case in 75 to 90 percent of orbital cellulitis cases. Injury to the skin around the eye can also cause this type of infection. The symptoms of orbital cellulitis include pain, swelling, and change in color of the skin around the eye. People with this condition may also have a fever, feel fatigued, and have disrupted vision or eye movement.
Periorbital Cellulitis
Periorbital cellulitis, also called preseptal cellulitis, is an infection of the eyelid and the skin around they eye. However, vision and eye movement remain directly unaffected in periorbital cellulitis, in contrast to orbital cellulitis, and the person usually does not experience a fever. Though vision is not directly affected, the skin around the eye may become so swollen that vision is obscured. Periorbital cellulitis is often caused by a spread of infection that begins due to trauma to the eye, or after insect or animal bites. The signs and symptoms of periorbital cellulitis are swollen, red, warm, and painful skin of the eyelid, and of the skin surrounding the eye.
