Dr. Connolly
Cellulitis is a common skin infection caused by bacteria. Dr. Alvarado, what can you tell us about cellulitis?

Dr. Alvarado
Well, Dr. Connolly, cellulitis affects the middle layer of skin, called the dermis, and the tissues below. Cellulitis is different than infections of the upper, surface layer of skin, a condition called erysipelas.

Cellulitis is usually the result of a bacterial invasion through a break in the skin, such as a scratch or cut, a crack or peeling, or an insect bite.

If cellulitis isn't treated or if treatment doesn't work, the infection can spread and cause serious complications. If infection spreads to the blood, it's called sepsis. Infection that spreads to the bones is called osteomyelitis. These are both serious conditions. Gangrene, or tissue death, is another potential complication of untreated cellulitis.