Empyema

An empyema (/ˌɛmpaɪˈiːmə/; from Ancient Greek ἐμπύημα (empúēma) 'abscess') is a collection or gathering of pus within a naturally existing anatomical cavity. The term is most commonly used to refer to pleural empyema,^[1] which is empyema of the pleural cavity. It is similar or the same in meaning as an abscess, but the context of use may sometimes be different. For instance, appendicular abscess is also formed within a natural cavity as the definition of empyema.

Empyema most commonly occurs as a complication of pneumonia but can also result from other infections or conditions that lead to the collection of infected fluid in a body cavity.^[2]