Abscess

A collection of pus formed as a result of infection by microorganisms, usually bacteria. Abscesses may develop in any organ and in the soft tissues beneath the skin in any area. Common sites include the armpit, breast (see breast abscess), groin, and gums (see abscess, dental). Rarer sites include the liver (see liver abscess) and the brain (see brain abscess). Common bacteria, such as staphylococci, are the usual cause of abscesses, although fungal infections can cause them, and amoebae are an important cause of liver abscesses (see amoebiasis). Infectious organisms usually reach internal organs via the bloodstream, or they penetrate tissues under the skin through a wound. An abscess may cause pain, depending on where it occurs. Most larger abscesses cause fever, sweating, and malaise. Those that are close to the skin often cause obvious redness and swelling. Antibiotics, antifungal drugs, or amoebicides are usually prescribed as appropriate. Most abscesses also need to be drained (see drain, surgical), and in some cases a tube may be left in place to allow continuous drainage. Some abscesses burst and drain spontaneously. Occasionally, an abscess within a vital organ damages enough surrounding tissue to cause permanent loss of normal function, or even death.