What is the term for a condition where pus accumulates within a capsule that must undergo incision and drainage?

The condition described as an accumulation of pus within a capsule that requires incision and drainage is referred to as an abscess. An abscess forms when an area of body tissue becomes infected, resulting in localized inflammation and the accumulation of pus, which is a thick fluid composed of dead white blood cells, bacteria, and tissue debris. The presence of this encapsulated pus requires a surgical procedure for drainage to alleviate pressure, remove the infection, and promote healing.

In contrast, a cyst is a closed sac that may contain fluid, air, or semi-solid material, and while they may need to be drained, they do not necessarily contain pus or indicate infection in the same way an abscess does. Hemorrhage refers to bleeding, which does not involve pus accumulation. A fistula is an abnormal connection between two body parts, often due to disease or injury, and does not specifically relate to pus collection or require drainage in the context defined. Thus, the term abscess accurately captures the specific nature of the condition in question.