Abcess

An abscess is a collection of pus that has accumulated in a cavity formed by the tissue on the basis of an infectious process (usually caused by bacteria or parasites) or other foreign materials (e.g. splinters or bullet wounds). It is a defensive reaction of the tissue to prevent the spread of infectious materials to other parts of the body.
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An abscess is an enclosed collection of liquefied tissue, known as pus, somewhere in the body. [more]Abcess - Community and Resources