What is a collection of pus surrounded by a wall of inflammatory tissue called?

A collection of pus surrounded by a wall of inflammatory tissue is known as an abscess. This condition occurs when the body responds to an infection, injury, or foreign body, leading to the accumulation of pus that is composed of dead cells, bacteria, and tissue debris. The body attempts to contain the infection by forming a wall of inflammatory tissue around the area where the pus has formed, which is what distinguishes an abscess from other types of pus accumulation or fluid collections in the body.

In the context of the other choices, a gumma is a soft, tumor-like growth that can occur in syphilis, while exudate refers to fluid that escapes from blood vessels into nearby tissues and may not specifically indicate pus. A carbuncle, on the other hand, is made up of interconnected furuncles (boils) and may contain multiple abscesses but is not synonymous with a single abscess itself. Hence, the term that accurately describes a localized collection of pus encased in inflammatory tissue is abscess.